• Domestic science and medicine in the 19th - early 20th centuries Chemistry of the 19th century in medicine
• What are peptides? Types and types of peptides. All about peptides and anti-aging cosmetics with peptides Additional peptides are not formed
• Toxic effect on humans of hazardous chemicals
• Radioautography Method of autoradiography in cytology
• Identification of bacteria by antigenic structure
• Organic matter in wastewater What are organic compounds in water
• Hydrogen index (pH factor)
• What is the pH of water and why is it important to know it?
• Redox potential Redox systems
• Reversible redox system Reversible redox systems

The fate of pollutants in natural waters develops in different ways. Heavy metals, once in a reservoir, are distributed in various forms, after which they are gradually carried away with the current, captured by bottom sediments or absorbed by aquatic organisms (primarily by binding to SH-groups), with which they settle to the bottom, and different forms of heavy metals absorbed to varying degrees.

Oil products practically do not mix with water and spread over its surface as a thin film, which is carried away by currents and, over time, is adsorbed on suspended particles and settles to the bottom. Dissolved petroleum products are also adsorbed on suspended particles, or oxidized by oxygen dissolved in water, and branched hydrocarbons are oxidized faster than unbranched ones. Also, oil products can be absorbed by aquatic microorganisms, but here the situation is reversed: branched ones are absorbed more slowly.

Surface-active substances are adsorbed on suspended particles and settle to the bottom. They can also be decomposed by some microorganisms. Some surfactants form insoluble salts with calcium and magnesium, but since such surfactants do not lather well in hard water, they are being replaced by substances that do not form insoluble salts. The behavior of surfactants that do not form insoluble salts is mainly described by kinetic models using the effective linear flow velocity from the water column to the bottom.

Fertilizers, once in a reservoir, are usually absorbed by living organisms, sharply increasing the biomass, but, in the end, they still settle to the bottom (although they can be partially extracted back from the bottom sediments).

Most organic substances, including pesticides, are either hydrolyzed or oxidized by dissolved oxygen, or (somewhat less often) bind to humic acids or Fe 3+ ions. Both oxidation and hydrolysis can be facilitated by certain microorganisms. Substances containing sulfur in low oxidation states, double bonds, aromatic rings with donor substituents are subjected to oxidation. The carbon atoms associated with oxygen and the carbon atoms at polarized bonds are also oxidized:

Halogen-containing compounds, as well as aromatic compounds with meta-orienting substituents (for example, NO 2 -group) and halogens, are oxidized much more slowly than unsubstituted analogs. Oxygen-containing groups in the molecule or o, n - orienting substituents (except for halogens) in the aromatic ring, on the contrary, accelerate oxidation. In general, the relative resistance of compounds to oxidation in water is about the same as in the atmosphere.

First of all, compounds containing polar carbon-halogen bonds undergo hydrolysis, ester bonds are much slower, and C-N bonds are even slower.

An increase in the polarity of the bond leads to an acceleration of hydrolysis. Multiple bonds, as well as bonds with the aromatic nucleus, are practically not hydrolyzed. Compounds in which one carbon atom has several halogen atoms are also poorly hydrolyzed. If acids are formed as a result of hydrolysis, then an increase in pH, as a rule, contributes to this process, if bases are formed, a decrease in pH contributes to an increase in hydrolysis. In strongly acidic media, the process of hydrolysis of C-O bonds is accelerated, but the hydrolysis of carbon-halogen bonds is slowed down.

Both the oxidation and hydrolysis of organic compounds are described by kinetic models and can be characterized by the half-life of these compounds. Hydrolysis catalyzed by acids and bases is described by more complex models, since its rate is very dependent on pH (Fig.).

This dependence is usually expressed by the equation

k \u003d k n + k a * 10 - pH + k b £ „ * 10 14 -pH,

where k is the total rate constant of hydrolysis, k n is the rate constant of hydrolysis in a neutral medium, k a is the rate constant of hydrolysis catalyzed by acid, k b is the rate constant of hydrolysis catalyzed by base.

The products of oxidation and hydrolysis, as a rule, are less dangerous for organisms than the starting materials. In addition, they can be further oxidized to H 2 O and CO 2 or assimilated by microorganisms. In the hydrosphere the second way is more probable. Chemically stable organic substances eventually end up in bottom sediments due to adsorption on suspensions or absorption by microorganisms.

In all reservoirs, the effective linear flow rates of dissolved substances to the bottom are usually much less than 10 cm/day, so this way of purifying reservoirs is rather slow, but very reliable. Organic substances that have fallen into bottom sediments are usually destroyed by microorganisms living in them, and heavy metals are converted into insoluble sulfides.

As a manuscript

IZVEKOVA Tatyana Valerievna

INFLUENCE OF ORGANIC COMPOUNDS CONTAINED IN NATURAL WATERS ON THE QUALITY OF DRINKING WATER (on the example of Ivanov)

Ivanovo - 2003

The work was performed at the State Educational Institution of Higher Professional Education "Ivanovo State University of Chemical Technology".

Scientific adviser: Doctor of Chemical Sciences,

Associate Professor Grinevich Vladimir Ivanovich

Official opponents: Doctor of Chemistry,

Professor Bazanov Mikhail Ivanovich Doctor of Chemistry, Professor Yablonsky Oleg Pavlovich

Lead organization: Institute of Chemistry of Solutions of the Russian

Academy of Sciences (Ivanovo)

The defense will take place on December 1, 2003 at 10 o'clock at a meeting of the dissertation council D 212.063.03 at the State Educational Institution of Higher Professional Education "Ivanovo State University of Chemical Technology" at the address: 153460, Ivanovo, F. Engels Ave., 7.

The dissertation can be found in the library of the State Educational Institution of Higher Professional Education "Ivanovo State University of Chemical Technology".

Scientific Secretary

dissertation council

Bazarov Yu.M.

The relevance of the work. The problem associated with the presence of various organic compounds in drinking water attracts the attention of not only researchers in various fields of science and water treatment specialists, but also consumers.

The content of organic compounds in surface waters varies widely and depends on many factors. The dominant of them is human economic activity, as a result of which surface runoff and precipitation are polluted with a variety of substances and compounds, including organic ones, which are contained in trace amounts, both in surface water and drinking water. Some substances, such as pesticides, polycyclic aromatic hydrocarbons (PAHs), organochlorine compounds (OCs), including dioxins, are extremely hazardous to human health even in microdoses. This determines their priority along with other ecotoxicants and requires a responsible approach when choosing a technology for water treatment, monitoring and quality control of both drinking water and water sources.

Therefore, the study of the content of CHOS both in the water of the water supply source, and the appearance of the latter in drinking water; Determining the risk to public health from short-term and long-term water use as a potential health hazard and for improving existing water treatment systems is of current importance. In the dissertation work, the study was carried out on the example of the Volsky reservoir, providing

80% of drinking water consumption by the population of Ivanov. __

The work was carried out in accordance with the thematic research plans of the Ivanovo State University of Chemistry and Technology (2000 - 2003), RFBR GRANT No. 03-03-96441 and the Federal Center for Scientific Research.

The main purpose of this work was to identify the relationship between water quality in the Uvodskoye reservoir and drinking water, as well as to assess the risk of carcinogenic and general toxic effects in the population. To achieve these goals, the following were carried out:

experimental measurements of the following most important indicators of water quality: pH, dry residue, COD, concentrations of phenols, volatile halocarbons (chloroform, people "~ [chloroethane,

Trichlorethylene, tetrachlorethylene, 1,1,2,2-tetrachloroethane), chlorophenols (2,4-dichlorophenol, 2,4,6-trichlorophenol) and pesticides (gamma HCCH, DDT), both in the source of water supply and drinking water;

The main sources and sinks of oil and phenol hydrocarbons in the Uvodsk reservoir have been determined;

Calculations of the risk values ​​for the occurrence of carcinogenic and general toxic effects and recommendations were developed to reduce the likelihood of their occurrence in water consumers.

Scientific novelty. Regularities of temporal and spatial changes in water quality in the source of water supply in the city of Ivanov are revealed. Relationships between the content of the main toxicants in the source of water supply and the quality of drinking water have been established, which allow, by varying the dose of chlorine or improving the water treatment system, to reduce the risks of developing adverse carcinogenic and general toxic effects. The relationship between the content of suspended organic matter and chlorophenols in the reservoir and drinking water has been established. It is shown that the content of chloroform is determined by the pH values ​​and permanganate oxidizability (PO) of natural water. For the first time, the risks of developing adverse organoleptic, general toxic and carcinogenic effects in citizens, as well as the associated reduction in life expectancy and damage to public health, have been identified.

Practical significance. For the first time, the main sources (Volga-Uvod canal and atmospheric fallout) and sinks of oil and phenol hydrocarbons (hydrodynamic removal, biochemical transformation, sedimentation and evaporation) in the Uvodskoye reservoir have been determined. In addition, the obtained experimental data can be used both to predict changes in the quality of water in the reservoir and drinking water. Recommendations are given on water intake from a controlled depth at certain times of the year, as well as for an ecological and economic justification for the need to modernize water treatment systems.

Basic provisions for defense. 1. Patterns of spatiotemporal and interfacial distribution of COS in a water body.

2. Correlation between the content of COS in the Uvod reservoir and in drinking water that has passed all stages of water treatment.

3. Results of balance calculations for the inflow and outflow of oil hydrocarbons and phenols from the reservoir.

4. The results of the calculation of the risk to the health of the population in the short-term and long-term use of treated water, the reduction in life expectancy (LLE) and the damages, expressed in monetary terms, caused to the health of the population of Ivanovo at the statistical cost of living (SLC) and damage according to « the minimum amount of liability insurance for damage to life, health ... ".

Publication and approbation of the work. The main results of the dissertation were reported at the III Russian scientific and technical seminar "Problems of drinking water supply and ways to solve them", Moscow, 1997; All-Russian scientific and technical conference "Problems of development and use of natural resources of the North - West of Russia", Vologda, 2002; II International scientific and technical conference "Problems of ecology on the way to sustainable development of regions", Vologda, 2003.

Dissertation volume. The dissertation is set out on 148 pages, contains 50 tables, 33 figs. and consists of an introduction, a literature review, research methods, a discussion of the results, conclusions, and a list of cited literature, including 146 titles.

The first chapter discusses the main sources and sinks of organic, including organochlorine compounds in natural surface waters, the mechanisms of formation and decomposition of organochlorine compounds in water. A comparative analysis of various methods of water treatment (chlorination, ozonation, UV radiation, ultrasound, X-ray radiation) is given, as well as the effect of one or another method of water disinfection on the content of COS in it. It is shown that at present there is not a single method and means without certain shortcomings, universal for all types of water treatment: preparation of drinking water, disinfection of industrial effluents, domestic sewage and storm water. Therefore, the most effective and cost-effective

The main goal is to improve the quality of natural waters in water supply sources. Thus, the study of the formation and migration of the main toxicants in each specific case of water supply is not only relevant, but also mandatory both for improving the quality of water in the source and for choosing a water treatment method.

The second chapter presents the objects of research: surface (Uvodskoye reservoir, Fig. 1) and underground (Gorinsky water intake) sources of water supply, as well as water from the city water supply.

The analysis of quality indicators was carried out according to certified methods: pH-potentiometric; dry residue and suspended solids were determined by the gravimetric method; chemical (COD), biochemical (BOD5) oxygen consumption and dissolved oxygen - titrimetrically, volatile phenols - photometrically (KFK-2M), oil products were determined by IR spectrophotometric method ("Srecors1-80M"), volatile halocarbons (chloroform, carbon tetrachloride , chlorethylenes, chloroethanes) were determined both gas chromatographically and

and photometric methods, chlorophenols and pesticides (gamma HCCH, DDT) - gas chromatographic methods (gas chromatograph of the Biolut brand with an electron capture detector (ECD)). The random error in measuring COS by chromatographic methods (confidence probability 0.95) did not exceed 25%, and the relative error in measuring all other indicators of water quality using standard methods did not exceed 20%.

Chapter 3. Water quality in the Uvodskoye reservoir. The chapter is devoted to the analysis of the spatio-temporal distribution of organic compounds and the influence of generalized indicators on them (Chapter 2). Measurements have shown that the change in the pH value does not go beyond the tolerance of the aquatic ecosystem.

pre-storage

We. except for a few measurements (stations: dam, canal). Seasonal changes - increased silkiness, a. consequently, the pH values ​​of water in the summer period are mainly associated with the processes of photosynthesis. Since 1996 (withdrawal), there has been a trend towards an increase in pH. respectively by years: 7.8 (1996); 7.9 (1997); 8.1 (1998); 8.4 (2000); 9.0 (2001). which, apparently, is associated with an increase in the bioproductivity of the reservoir and the accumulation of biomass in the water. This indicates a gradual increase in the trophic level of the reservoir.

An analysis of the content of organic substances (Fig. 2) in the water of the Uvodsk reservoir from 1993 to 1995 showed an increase in their content to 210 mg/l, with dissolved organic substances up to 174 mg/l, and in suspended form their content increased to 84%. The largest amount of dissolved organic matter is noted in the area of ​​the village of Rozhnovo, and suspended organic matter is more or less evenly distributed over the reservoir.

The study of the content of organic substances in the composition of dissolved and suspended forms at the water intake showed that during the phases of stable water exchange, the bulk of organic compounds are in a dissolved or colloid-dissolved state (93-98.5%).

During the flood (2nd quarter), the content of organic compounds, both in dissolved and suspended form, increases, and suspended forms account for 30-35% of the total content of organic substances. 01menp is required. that in the phases of stable water exchange, the content of organic compounds in the water intake area is higher than in the winter months. Apparently, this is due to more intense processes of oxidation, photosynthesis, or hydrolysis of a part of organic substances (possibly oil products) and their transfer into a dissolved state.

The value of software changed during 1995-2001 1. within (mg Oo/l): 6.3-10.5; average annual values ​​were: 6.4-8.5. The content of biochemically oxidizable organic compounds (BOD5) in the water of the Uvodsk reservoir

■ Q1 Q2 QQ Q4 Q4

Nilisha ranged from 1.1 - 2.7 mg O2 / l at normalized values ​​of 2 mg Og / l according to BOD5, and PO - 15 mg Og / l.

The maximum value of cytotoxicity of solutions subject to oxidation (chlorination, ozonation) occurs at a minimum BOD/PO ratio, which indicates the presence of biologically inoxidizable compounds in the solution. Therefore, under certain conditions, the oxidation of substituted compounds can lead to the formation of intermediate products with higher cytotoxicity.

The measurement results (Table 1) show that there is a tendency for the BOD5/PO ratio to decrease, which indicates the accumulation of difficult-to-oxidize organic substances in the reservoir and is a negative factor for the normal functioning of the reservoir, and, as a result, the likelihood of COS formation during water chlorination increases.

Table 1

Seasonal change in BOD5/LD ratio_

Season BODz/LD value

1995 1996-1997 1998 2000-2001

Winter 0.17 0.17 0.15 0.15

Spring 0.26 0.23 0.21 0.21

Summer 0.13 0.20 0.20 0.19

Autumn 0.13 0.19 0.19 0.18

Avg. 0.17 0.20 0.19 0.18

Over the entire period under study, the amount of dissolved oxygen in the Uvodskoye reservoir never fell below the norm and the absolute values ​​are close to each other over the years. In summer, due to an increase in the intensity of photosynthesis processes, the concentration of dissolved oxygen drops to an average of 8.4 mg/l. This leads to a decrease in the intensity of oxidative processes of pollutants, however, an adequate increase in the content of organic compounds (OC) in the 3rd quarter is not observed (Fig. 2). Consequently, the main channels of OS decomposition are either photochemical processes or reactions of hydrolysis and biochemical oxidation rather than chemical oxidation.

Control over the content of organic substances (Fig. 3) in the water area of ​​the reservoir showed that the average content of volatile phenols and oil hydrocarbons is maximum in the spring period and is about 9 and 300 MPC.x. respectively. Particularly high concentrations are observed in the area of ​​the village of Mikshino (14 and 200 MPCr.ch.), the village of Rozhnovo (12 and 93 MPCr.kh.) and near the village of Ivankovo

more than 1000 MPC.x. (on oil products). Consequently, the accumulation of biochemically difficult to oxidize organic substances in the water of the Uvodskoye reservoir is a consequence of the pollution of the reservoir, which explains the increase in the value of PO.

1 quarter mg/l

2nd quarter u-

3 quarter 5 -

4 quarter O

12 3 4 Oil products

Rice. Fig. 3. Spatio-temporal distribution of volatile phenols and oil products from time of year by stations (1995): 1) dam, 2) Mik|ni1yu, 3) kanal, 4) Rozhnovo, 5) Ivankovo.

To clarify the main reasons for the "increased content of phenols and oil hydrocarbons (OP) in the water of the reservoir, their content in atmospheric precipitation was measured (Table 2), which made it possible to determine the main sources and sinks of these compounds in the reservoir from the balance equation (Table 3).

table 2

Concentrations of phenols and oil hydrocarbons in atmospheric fallout in

Indicator Snow cover* Rainfall

1 2 3 4 15 1 Avg.

Phenols, μg/l 17 12 15 8 19 IV 12

NP. mg/l 0.35 pt 0.1 pt 0.05 0.1 0.3

*1) dam, 2) Mnkshino, 3) canal, 4) Rozhnovo, 5) Ivankovo.

Table 3

Sources and sinks of phenols and oil hydrocarbons in the Uvodskoye reservoir

Compound Sources of income, t/year 2, t/year Sources of output, t/year* A. t/year

Rain runoff Snowmelt water Runoff R-Uvod Volga-Uvod Canal GW, t/year BT, t/year U, t/year

Phenols 0.6 0.3 0.5 0.8 2.2 1.1 0.3 0.6 -0.2 (8.5%)

NP 13.76 2.36 156.3 147.7 320.1 111.6 93.6 96.0 -18.9 (5.9%)

* GV - hydrodynamic removal: BT - transformation (biochemical), I - evaporation; X - total receipt; D - the difference between income and expenditure items.

Contamination of atmospheric fallout with NPs, compared with their content in a reservoir during a spring flood, is small and amounts to 0.1 mg/l for snow (2 MPCpit), and for rain 0.3 mg/l (6 MPCpit), therefore, increased concentrations of NPs, observed in spring (Fig. 3) in the water of the Uvodskoye reservoir are caused by other sources. Table data. 3 show the following:

The main sources of oil hydrocarbons entering the Uvodskoye reservoir are the Volga-Uvod canal and the runoff of the Uvod River (approximately 50% each), atmospheric precipitation and melt water do not significantly affect the OP content in the reservoir water;

For phenols, the main sources are all considered channels of entry: the Volga-Uvod canal - 36%, rain runoff - 26%, runoff of the river. Take away - 23%, melt water - 15%;

The main excretion channels were determined: for phenols - hydrodynamic removal (~ 50%); for NP - hydrodynamic removal, evaporation and biochemical transformation -34.30.29%, respectively.

Measurements of the content of total organic chlorine, including volatile, adsorbable and extractable COS (Fig. 4), showed that the total content of COS in terms of chlorine in the reservoir is maximum during the spring water exchange in the area of ​​the village of Ivankovo ​​- 264 and summer period - 225 μg / l ("Mikshi-no"), and in the autumn - the channel, Ivankovo ​​(234 and 225 mcg / l, respectively).

■ 1 quarter

□ 2 quarter

□ Q3 Q4

1 2 3 4 5 among the crucibles.

It should be noted that if in 1995-96. in the water intake area, within the sensitivity of the methods, COS were not always detected, then in 1998 chloroform was recorded in 85% of measurements, and carbon tetrachloride in 75%. The range of variable values ​​for chloroform ranged from 0.07 to 20.2 µg/l (average - 6.7 µg/l), which is 1.5 times higher than MPC.ch., and for SCC from 0.04 to 1 .4 µg/l (on average 0.55 µg/l), in the normalized absence of it in the watercourse. The concentrations of chloroethylene in the water of the reservoir did not exceed the normalized values, however, in the summer of 1998, "tetrachlorethylene was registered, the presence of which in natural waters is unacceptable. Measurements carried out in 1995 - 1997 showed the absence of 1,2 - dichloroethane and 1,1,2 ,2-

tetrachloroethane. but in 1998, the presence of 1,2-dichloroethane was found in the water intake area during the spring water exchange.

Chlorphenols in the Uvodskoye reservoir accumulate mainly in the bottom layers of water, and during the flood (2nd quarter), their concentration increases. A similar distribution is observed for suspended and dissolved organic substances (Fig. 2). Thus, there is a good correlation between the increase in the content of suspended solids (correlation coefficient 11=0.97), namely, organic suspensions (12.5 times) and the concentration of chlorophenols in the water of the reservoir (Fig. 5).

C, µg/dm* In the phase of sustainable water supply

2,4-dichlorophenol / mena content of chlorophenols in

2,4,6-trichlorophenol/. water intake area maximum,

which, apparently, is associated with the movement of toxicants into the surface

weighed in layers from the bottom layers, from-

60 70 80 wt.%

having a higher content

Rice. Fig. 5. Dependence of the concentration of chlorine, in g, of suspended organic phenols on the content of suspended

organic matter. substances.

During the entire period of research, γ-HCH, DDT and its metabolites were not found in the water of the Uvodsk reservoir and drinking water. The expected decrease in the content of OS as a result of the dilution process in the water samples taken at successive stations (Rozhnovo, Mikshino, Ivankovo) does not occur. For example, at the Rozhnovo station, the average concentrations of phenols, OP. chloroform, trichlorethylene. The software is in shares of MPCrx, respectively, 8.7: 56;<0,5; 0,02; 0,85. На станции «Микшино» средние концентрации составляю! соответственно - 8.9: 110; 2.9; 0.03; 0.73.На станции «Иванково» - 7,0; 368: 6.75; 0.36; 0,55. Таким образом, явление разбавления характерно для фенолов и других, трудно окисляемых соединений (ПО); для НП. хлороформа и трихлорэтилена отмечается явный рост концентраций.

A somewhat different situation is noted at the stations "Kanal" and "Dam". Dilution processes are shown here for all measurable compounds.

The average concentrations of phenols, NP, chloroform, trichlorethylene, PO at the station "Kanal" are in shares of MPCrx, respectively - 7.4; thirty; 0.7; 0.04, 0.55; the average concentrations at the Plotina station are 4.8; ten;<0,5; 0,02; 0,61. Наблюдается рост концентраций трудно окисляемых соединений (по результатам замеров ПО, БПК5/ПО) у верхнего бьефа плотины, что связано с гидродинамическим переносом с акватории водохранилища.

Chapter 4. The relationship of water quality in the source of water supply and drinking water. During the entire observation period, there is a relationship between the content of organochlorine compounds in the Uvodskoye reservoir and in drinking water after the chlorination process. The total content of organochlorine compounds in terms of chlorine is maximum in the clean water reservoir at the entrance to the mining collector in all observed periods (Fig. 4). Note that the increase in this indicator after chlorination of water from an underground source is insignificant (1.3 times), and the maximum value is 88 µg/l.

Table 4

Annual dynamics of COS content in the Uvodskoye reservoir

■ Indicator ■ -■■ ......- Average value, μg / dm * MPCr.h.,

1995** 1996-1997 1998 mcg/dm3

Chloroform<5-121 /8,6 <5-12,6/8,0 1,4-15,0/7,8 5

SSC<1-29,4/1,3 <1 0,08-1,4/0,5 отс.

1,2-dichloroethane___<6 <6 <0,2-1,7/0,6 100

Trichlorthylene<0,4-13/0,81 <0,1-0,1 /0,05 <0,1-0,1 /0,03 10

Tetrachlorethylene - -<0,04-0,1 /0,02 отс.

1,1,2,2-tetrachloroethane - -<0,1 отс.

2,4-dichlorophenol -<0,4-3,4/1,26 <0,1-2.1 /0,48 О 1С.

2,4,6-trichlorophenol j<0.4-3,0/1,3 | <0,4-2,3/0,43 ОТС.

♦min - shak/(annual average); ** - average data from 6 observation stations.

There is a favorable trend for the reservoir ecosystem to decrease the content of all controlled COS (Table 4), but the average annual concentrations of chloroform, carbon tetrachloride, tetrachlorethylene, 2,4-dichlorophenol and 2,4,6-trichlorophenol exceed the corresponding

MPC, i.e. aquatic ecosystems experience increased loads on these compounds.

After chlorination, the concentrations of COS in drinking water increase, but do not exceed the relevant standards established for drinking water, except for 2,4-dichlorophenol (Table 5).

Table 5

Annual dynamics of CHOS content in drinking water

Index Mean value, mcg/dm"1 *

1995 1996-1997 1998 2000 2001 MPCp**

Chloroform 7.8-35.2 5.6-24.6 5.0-43.5 3.2-38.6 5.0-24.4 200/30

(18,3) (12,2) (11,3) (10,95) (9,3)

SSC<1 <1 0.2-0.86 (0,5) 0,2-1,2 (0,53) 0.2-1.1 (0,51) 6/2

1,2-dichloroethane<6-8,6 <6 <6 <0.2-6.0 (1,4) <0.2-2.5 (1,18) <0.2-1.3 (0,74) 20/10

Trichlorethylene<0,4-0,4 <0,4 <0,4 <0.1-0.7 (0,18) <0.1-0.2 (0,1) <0.1-0.4 (0,16) 70/3

Tetrachlorethylene -<0.04-0.1 (0,06) <0,040,1 2/1

1,1,2,2-tetrachloroethane - -<0,1 <0,10.12 <0,1 200

2,4-dichlorophenol - 0.4-5.3<0.1-4.3 <0.1-2.1 0.1-0.4 2

(1,6) (1,43) (0,7) (0,3)

2,4,6-trichlorophenol -<0,4-2,8 (0,92) <0.4-3.1 (1,26) <0.4-1.3 (0,78) <0,4 4/10

Gamma HCCH DDT -<0,002 2/отс

*max - tt / (average annual values); **MAC" - RF standards/ - WHO standards.

C1 Periodically (in separate months) on-

I-S-S-S! oJ-C-O "+ SNCH, an increased content of chlo-O C1 O roform was observed relative to the norms recommended

WHO bathrooms. The amount of chloroform formed is determined by the pH and PO values ​​of natural water (Fig. 7), which does not contradict the literature data.

Periodically (in some months) there was an increased content of chloroform relative to the norms recommended by WHO. The amount of chloroform formed is determined by the pH and PO values ​​of natural water (Fig. 7), which does not contradict the literature data.

The concentration of 2,4-dichlorophenol exceeded the normalized value (MPC -2 µg/l) in 30% of measurements by an average of 40-5-50% during the entire period

observations. It should be noted that the maximum concentrations of chlorophenols in drinking water were observed in summer (Q3), which correlates with their content in the water intake area.

C HF, µg/dm3

Rice. Fig. 7. Interrelation of chlorine content. Fig. 8. Correlation between the content of chloroform in drinking water from pH (1) chlorophenols in drinking water and chlorphe-iCOD (2) in natural water nols (1), suspended organic

(I, = 0.88; = 0.83). compounds (2) in natural water

(K| - 0.79; K2 - 0.83).

There is a tendency to increase chlorophenols in drinking water: 2,4-dichlorophenol on average 2 times, and 2,4,6-trichlorophenol - 1.3 times in the summer. There is a good correlation (Fig. 8) between the concentration of chlorophenols in drinking water, as well as their concentration and the content of suspended organic compounds in natural water.

Due to the fact that the concentrations of chlorophenols in the bottom layers are higher and are predominantly in suspension, it is necessary to improve the process of water filtration, as well as to carry out water intake from a controlled depth. especially in spring and summer.

Chapter 5. Assessment of the impact of drinking water on public health. By using

computer program "Clean Water". developed by the research and production association "POTOK" in St. Petersburg, an assessment was made of the conformity of drinking water according to koshrolir>emy\1 indicators and an assessment of the risk of disruption in the functioning of human organs and systems when drinking water that has undergone water treatment was carried out (1 table 6) .

The results of the calculation show a decrease in the risk of adverse organoleptic effects when drinking water is consumed, both immediate and chronic intoxication relative to natural water in the water intake area. A significant part of it is contributed by such indicators as phenols and their chlorine derivatives (2,4-dichlorophenol and 2.4,6-trichlorophenol). On the other hand,

rona after the water treatment process increases (1.4 times) the risk of carcinogenic effects (chloroform, carbon tetrachloride and trichlorethylene) and general toxic risk: chronic action by 4-5 times and total by 2-3 times, which form phenols, chloroform, carbon tetrachloride , 1,2-dichloroethane and trichlorethylene.

Table 6

Risk calculation results for 1998_

Indicators Risk

Surface Bottom Drinking

Risk of developing adverse organoleptic effects (immediate effect) 0.971 0.999 0.461

Risk of adverse organoleptic effects (chronic intoxication) 0.911 0.943 0.401

Risk of carcinogenic effects 0.018 0.016 0.21

General toxic risk (development of chronic intoxication) 0.001 0.001 0.005

General toxic risk (total) 0.003 0.003 0.008

The data obtained made it possible to identify priority pollutants from among the

la investigated, such as chloroform, carbon tetrachloride and trichlorethylene, 1,2-dichloroethane, 2,4-dichlorophenol and 2,4,6-trichlorophenol, which make a significant contribution to the total general toxic risk.

The found values ​​of the probabilities of manifestation of general toxic and carcinogenic effects significantly exceed the normalized risk value. The acceptable (acceptable risk) from substances with carcinogenic properties lies in the range of 1 (G4 to 10-6 people / person-year, that is, the values ​​​​of the risk of disease and death when drinking water are not acceptable.

It is shown that the current state of drinking water consumed by the population of Ivanovo leads to a deterioration in his health and, as a result, a reduction in life expectancy: men - 5.2; women - 7.8 years (Table 7).

Table 7

Reduction in expected duration for populations___

Name of risk (R), share rel. units 1XE \u003d b x K, year

Men Women

Average life expectancy 56 71

Average age of the population 37 42.3

Expected remainder i<изни 19 28.7

Risk of developing adverse organoleptic effects (immediate action) 0.157 An indicator that characterizes the occurrence of unstable negative reactions of the body to the consumed drinking water (allergic reactions, etc.). Organolep. immediate indicators. actions in most cases do not lead to BE.

Continuation of the table. 7

Risk of developing adverse organoleptic effects (chronic intoxication) 0.09 An indicator that characterizes the occurrence of persistent negative reactions of the body to the consumed drinking water (acquired "global" allergy, respiratory diseases, anemia, etc.)

Risk of carcinogenic effects 0.02 Indicator characterizing the occurrence of mutagenic and carcinogenic effects in the human body (cancer, DNA changes, etc.)

General toxic risk (development of chronic intoxication) 0.006 An indicator that characterizes the development of human diseases of the respiratory system, endocrine system, urinary tract, etc.

le 0.11 0.17

£1XE, year 5.2 7.8

The calculation results show that the greatest reduction in duration

life expectancy is determined by factors that form unfavorable organoleptic effects, the magnitude of which is determined by the content of phenols and their chlorine derivatives (Table 6).

In practice, an economic assessment of the impact of the environment on health is used, which is based on the cost of living and the amount of fees for restoring health. Therefore, the damage (Y) to the health of the population of Ivanovo (450 thousand people) from the consumption of drinking water that has been prepared was calculated at the statistical cost of living (Table 8) and the damage at the “minimum amount of liability insurance for causing harm to life, health, or property of other persons and the natural environment in the event of an accident at a hazardous facility” (Table 9).

Table 8

Calculation of the amount of damage based on the statistical cost of living (CVL)*

Population in Ivanovo, persons Men (164000) Women (197250)

BE from the consumption of poor-quality drinking water per person, years 5.2 7.8

Average (expected) life expectancy, years 56 71

Damage from the reduction of life expectancy of 1 person, expressed in monetary terms, € 3496.6 4407.4

Total damage, € 0.96 billion

* SCV = GDP х Тср / N. where GDP - gross domestic product, rub; T^, - average life expectancy, years; N - the number of population, people.

Table 9

Calculation of the amount of damage, based on the "minimum sum insured"

Damage from the reduction of life expectancy of the 1st person, expressed in monetary terms, € Men Women

Total damage, €** 0.3 billion

** the basis of art. 15 of the Law of the Russian Federation "On industrial safety of hazardous facilities" No. 116-FZ (clause 2)

From the obtained values ​​(Tables 7-9), on the territory of Ivanovo there is an area of ​​unacceptable environmental risk (Yu.-.Yu "4), requiring environmental protection measures, regardless of the scale of financial costs. It is important to note that the calculated level environmental risk cannot be due to the consumption of drinking water alone.

Since the main problem in the water treatment system is the formation of COS during water chlorination, and due to the large length of pipelines in the city, chlorination cannot be completely excluded from the water treatment process, this can be done by replacing chlorine at the 1st stage of chlorination with another oxidizing agent, which is ozone is offered, and at the 2nd stage - chlorination.

Main results and conclusions

1. It has been established that the change in the content of organic compounds in the Uvodskoye reservoir over time tends to decrease, although the concentrations of oil products and volatile phenols are still significantly higher than the normalized values ​​up to 42 and 4 MPC.x. respectively.

2. It is shown that there is no decrease in the content of organic compounds as a result of the dilution process at successive stations (Rozhnovo, Mikshino, Ivankovo). The dilution phenomenon is typical only for phenols, while for oil products, chloroform and trichlorethylene there is a clear increase in concentrations, which is associated with additional sources of income (diffusion from interstitial waters, surface runoff).

The main sources of oil hydrocarbons entering the Uvodskoye reservoir are the Volga-Uvod canal and the runoff of the Uvod River (at

approximately 50% each), atmospheric precipitation and melt water do not have a great influence on the content of oil products in the water of the reservoir;

The main excretion channels were determined: for phenols - hydrodynamic removal (~ 50%); for oil products - hydrodynamic removal, evaporation and biochemical transformation - 34.30.29%, respectively.

4. It is shown that the concentrations of COS in drinking water are interrelated both with the processes inside the reservoir and with the process of water disinfection - chlorination.

7. The current state of drinking water consumed by the population of Ivanovo leads to a deterioration in his health and, as a result, a reduction in life expectancy (men - 5 years, women - 8 years, 2001). The amount of financial loss is estimated at 0.3 billion €/year, and based on the statistical cost of living, at 0.96 billion €/year.----

8. It has been shown that chlorophenols in the water of the Uvodskoye reservoir are mainly in the composition of suspended matter, therefore it is recommended to improve the filtration process in order to reduce their concentration in drinking water, as well as to carry out water intake from a controlled depth, especially in the spring-summer period.

1. Grinevich V.I., Izvekova T.V., Kostrov V.V., Chesnokova T.A. Correlations between the quality of water in a watercourse and drinking water supply // Tez. report at the 3rd Russian scientific and technical seminar "Problems of drinking water supply and ways to solve them", Moscow. -1997.-S. 123-125.

2. Grinevich V.I., Izvekova T.V., Kostrov V.V., Chesnokova T.A. Sources of organochlorine compounds in drinking water in Ivanovo // Journal "Engineering Ecology" No. 2,1998. - S. 44-47.

3. Grinevich V.I., Kostrov V.V., Chesnokova T.A., Izvekova T.V. Quality of drinking water in Ivanovo. // Collection of scientific papers "Environment and human health" // Ivanovo, 1998. - S. 26-29.

4. Izvekova T.V., Grinevich V.I., Kostrov V.V. Organochlorine compounds in drinking water // Tez. report "Problems of the development and use of natural resources of the North-West of Russia: Materials of the All-Russian Scientific and Technical Conference." - Vologda: VoGTU, 2002. - P. 85-88.

5. Izvekova T.V., Grinevich V.I., Kostrov V.V. Organochlorine pollutants in the natural source of water supply and in the drinking water of the city of Ivanov // Journal "Engineering Ecology" No. 3,2003. - S. 49-54.

6. Izvekova T.V., Grinevich V.I. Organic compounds in the water of the Uvodskoye reservoir // Tez. report At the second International scientific and technical conference "Problems of ecology on the way to sustainable development of regions". - Vologda: VoGTU, 2003. - S. 212 - 214.

License LR No. 020459 dated 10.04.97. Signed for printing 27.10.2003 Paper format 60x84 1/16. Circulation 90 copies. Order 2 "¡> $. Ivanovo State University of Chemical Technology. 153460, Ivanovo, pr. F. Engels, 7.

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Izvekova T.V.

Introduction.

Chapter 1 Literary review.

§ 1-1 Sanitary and hygienic characteristics of organic pollutants of drinking water.

§1.2 Sources of formation of organochlorine compounds.

§ 1.3 Basic methods of drinking water preparation.

Chapter 2. Methods and object of experimental research.

§2.1 Physical and geographical characteristics of the Uvodskoye reservoir area.

§ 2.2 ONVS - 1 (m. Avdotino).

§ 2.3 Methods for determining the concentrations of organic and inorganic compounds.

§ 2.3.1 Taking water samples and preparing for analysis.

§2.3.2 Instrumental methods for the study of HOS.

§ 2.4 Determination of volatile organohalogen compounds in water

§2.4.1 Definition of chloroform.

§ 2.4.2 Determination of carbon tetrachloride.

§2.4.3 Definition of 1,2-dichloroethane.

§ 2.4.4 Determination of trichlorethylene.

§ 2.5 Determination of organochlorine pesticides (y-HCCH, DCT).

§2.5.1 Determination of chlorophenols (CP).

§ 2.6 Quality assessment and processing of measurement results.

§ 2.7 Definition of generalized indicators of water quality.

Chapter 3. Water quality in the Uvodskoye reservoir.

§ 3.1 Main indicators of water quality in the Uvod reservoir.

§3.1.1 Effect of pH change.

§ 3.1.2 The ratio of suspended and dissolved substances in a reservoir.

§3.1.3 Dissolved oxygen.

§3.1.4 Changes to BOD5, COD.

§ 3.2 Toxic substances (phenol, oil products).

§3.2.1 Influence of precipitation.

§ 3.2.2 The main sources and sinks of oil and phenol hydrocarbons in the Uvodskoye reservoir.

§ 3.3 Chlorinated hydrocarbons in the water of the Uvodsk reservoir.

Chapter 4 Interrelation of water quality in the source of water supply and drinking water.

§ 4.1 Quality of drinking water in Ivanovo.

§ 4.2 Influence of water quality in the water supply source on drinking water.

§ 4.3 Quality of fresh groundwater.

Chapter 5 Assessment of the impact of drinking water on public health.

§5.1 Comparative public health risk assessment.

§ 5.2 Risk assessment for reduced life expectancy. Calculation of the damage to the health of the population according to the statistical cost of living.

§ 5.4 Substantiation of the need to reconstruct the water treatment system at ONVS - 1.

Introduction Thesis in biology, on the topic "The influence of organic compounds contained in natural waters on the quality of drinking water"

The problem of the content of various organic compounds in drinking water attracts the attention of not only researchers in various fields of science and water treatment specialists, but also consumers. C The content of organic compounds in surface waters varies widely and depends on many factors, the main of which is human economic activity, as a result of which surface runoff and precipitation are polluted with various substances and compounds, including organic ones. A certain role in the pollution of surface natural waters is played by agricultural effluents, which are inferior to industrial effluents in terms of the scale of local receipts of ecotoxicants, but due to the fact that they are distributed almost everywhere, they should not be discounted. Agricultural pollution is associated with deterioration in the quality of surface waters of small rivers, as well as, to a certain extent, groundwaters associated with natural watercourses at the level of upper aquifers.

The complexity of the problem lies in the fact that the set of organic pollutants contained in microquantities, both in surface water and drinking water, is very wide and specific. Some substances, such as pesticides, PAHs, organochlorine compounds (OCs), including dioxins, are extremely hazardous to human health even in microdoses. One of the main reasons for the unsatisfactory quality of drinking water is the high content of chlorinated hydrocarbons in it. This determines their priority along with other dangerous ecotoxicants and requires a responsible approach when choosing a technology for water treatment, monitoring and quality control of both drinking water and water sources.

Most researchers have long come to the conclusion that in order to determine the specific causes and sources of the formation of chlorine-containing hydrocarbons, it is necessary to know the composition of organic compounds contained in natural waters used as a source of water supply. Therefore, the Uvodskoye reservoir was chosen as the object of study, which is the main source of water supply for the city of Ivanovo (80% of the total water consumption), as well as drinking water after the water treatment process.

For most COS, the maximum allowable concentrations (MACs) are set at the level of micrograms per liter and even less, which causes certain difficulties in choosing methods for their control. Elevated concentrations of such compounds in drinking water are extremely dangerous for consumers. Carbon tetrachloride, chloroform and trichlorethylene are suspected of being carcinogenic, and an increased content of such compounds in water, and, consequently, in the human body, causes destruction of the liver and kidneys.

Thus, the study of the causes of the appearance of chlorinated hydrocarbons in drinking water depending on the source of water supply, the determination of their concentrations and the development of recommendations to reduce the risk of carcinogenic and non-carcinogenic effects in drinking water consumers is relevant. This was precisely the main goal of this study.

1. LITERATURE REVIEW

§ 1.1. Sanitary and hygienic characteristics of organic pollutants of drinking water

According to the World Health Organization (WHO), out of 750 identified chemical contaminants in drinking water, 600 are organic compounds, which are grouped as follows:

Natural organic substances, including humic compounds, microbial exudants and other waste products of animals and plants dissolved in water;

Synthetic pollution, including pesticides, dioxins and other substances produced by industry;

Compounds added or formed during water treatment, in particular chlorination.

These groups logically designate the ways in which organic pollutants get into drinking water. In the same work, it is noted that these 600 substances represent only a small part of the total organic material present in drinking water. Indeed, the progress made in improving analytical methods has recently made it possible to identify and enter into computer memory about 300 organic compounds found in groundwater, surface water and drinking water.

On fig. 1 shows some of the routes of entry and possible transformations of pollutants in surface waters. Pollution of underground water sources occurs mainly through the soil. Thus, the accumulation of purposefully introduced organochlorine pesticides in the soil leads to their gradual penetration into the groundwater of underground drinking sources. According to the work, a third of artesian wells intended for drinking water supply in the USA alone were closed for this reason. Organochlorine compounds are most often found in groundwater. According to generally accepted international terminology, they are called DNAPL (dense non-aqueous phase liquids), i.e. heavy non-aqueous liquids (TNVZH). Non-aqueous means that they form a separate liquid phase in water like petroleum hydrocarbons. Unlike oil hydrocarbons, they are denser than water. These substances are also called dense water-immiscible liquids. At the same time, their solubility is quite sufficient to cause pollution of groundwater. Once in groundwater, COS can remain there for decades and even centuries. They are removed from aquifers with great difficulty and therefore represent a long-term source of pollution of groundwater and the environment in general.

Rice. 1. Scheme of COS migration in a stagnant water body

The WHO guidance notes that the recommended values ​​tend to be biased towards over-caution due to insufficient data and uncertainties in their interpretation. Thus, the recommended values ​​of permissible concentrations indicate tolerable concentrations, but do not serve as regulatory figures that determine water quality. Thus, the US Environmental Protection Agency, for the content of chloroform in drinking water, proposed as a standard value not 30, but 100 µg/l. The standard for trichlorethylene is 5 times lower than that recommended by WHO, and for 1.2 dichloroethane it is 2 times lower. At the same time, the standards adopted in the USA for carbon tetrachloride are 2 times, and for 1,1-Dichloroethylene 23 times higher than those recommended by WHO. This approach also seems legitimate from the point of view of WHO experts, who emphasize that the values ​​they propose are only advisory in nature.

Chloroform 30

1,2 - Dichloroethane 10

1.1- Dichloroethylene 0.3

Pentachlorophenol 10

2,4,6 - Trichlorophenol 10

Hexachlorobenzene 0.01

In table. Table 1.1 shows the recommended concentrations of pollutants in water, established on the basis of toxicological data and data on carcinogenicity, taking into account the average human body weight (70 kg) and the average daily water consumption (2 l).

The permissible content of organochlorine compounds (OCs) in natural and drinking water according to the Ministry of Health of the Russian Federation and their toxicological characteristics are summarized in Table. 1.2.

Among the many organic contaminants of drinking water, the attention of hygienists is especially drawn to those compounds that are carcinogenic. These are mainly anthropogenic pollutants, namely: chlorinated aliphatic and aromatic hydrocarbons, polycyclic aromatic hydrocarbons, pesticides, dioxins. At the same time, it should be noted that chemical pollutants in water are capable of undergoing various chemical transformations under the influence of a complex of physicochemical and biological factors, leading both to their complete disintegration and to partial transformation. The result of these processes can be not only a decrease in the adverse effect of organic pollutants on water quality, but sometimes even its strengthening. For example, more toxic products may appear during the breakdown and transformation of certain pesticides (chlorophos, malathion, 2,4-D), polychlorinated biphenyls, phenols, and other compounds.

Table 1.2.

Permissible concentrations and toxicological characteristics of some

Compound MPC, µg/l Hazard class Nature of impact on the human body

Drinking water Natural waters (r.h.) TAC*

Harm factor ***

Chloroform 200/30** 5/60 2 Social-T. A drug that is toxic to the metabolism and internal organs (especially the liver). Causes carcinogenic and mutagenic effects, irritates mucous membranes.

Carbon tetrachloride 6/3** ots / 6 2 Social-T. Drug. It affects the central nervous system, liver, kidneys. It has a local irritant effect. Causes mutagenic, carcinogenic effects. Highly cumulative compound.

1,2-dichloroethane 20/10** 100/20 2 Social-T. polytropic poison. It affects the cortical-subcortical regions of the brain. Drug. It causes dystrophic changes in the liver, kidneys and disrupts the functions of the cardiovascular and respiratory systems. Has an irritating effect. Carcinogen.

1,1,2,2-tetrachloroethane 200 ots / 200 4 org. Drug. Damages parenchymal organs. Has an irritating effect.

Grichlorethylene 70/3** 10/60 2 Social-T. The drug has neurotoxic and cardiotoxic effects. Carcinogen.

Pentachlorophenol 10** ots /10 2 Social-T. It has a high lipophilicity, accumulating in fatty deposits and is very slowly excreted from the body

Tetrachloroethylene 2/1** ots / 20 2 Social-T. It acts similarly to trichlorethylene, depresses the central and peripheral nervous systems. The hypnotic effect is stronger than that of the SCS. Affects the liver and kidneys. Has an irritating effect.

Continuation of the table. 1.2.

2-chlorophenol 1 ots / 1 4 org. They have moderate cumulative properties. Violate the function of the kidneys and liver.

2,4-dichlorophenol 2 ots /2 4 org.

2,4,6-tri-chlorophenol 4/10** ots /4 4 org.

Gamma HCCH 2 / ots** ots /4 1 s.-t. Highly toxic neurotropic poison with embryo-toxic and irritating effects. It affects the hematopoietic system. Causes carcinogenic and mutagenic effects.

DDT 2 / ots* * ots /100 2 social-t. - Approximately permissible levels of harmful substances in the water of reservoirs for domestic and drinking water use. - "orienting" standards established in accordance with WHO recommendations

15] and EU Directive 80/778 on the quality of drinking water . - the limiting sign of the harmfulness of the substance for which the standard is established:

S.-t. - sanitary and toxicological indicator of harmfulness; org. - organoleptic indicator of harmfulness.

The most common mechanisms for the destruction of COS in the environment can be considered photochemical reactions and, mainly, the processes of metabolic decomposition with the participation of microorganisms. Photochemical decomposition of COS in molecules containing aromatic rings and unsaturated chemical bonds occurs as a result of the absorption of solar energy in the ultraviolet and visible regions of the spectrum. However, not all substances are prone to photochemical interaction, for example, lindane (y-HCH) under UV irradiation only isomerizes into a-HCH. The scheme of the proposed mechanism of the photochemical conversion of DDT is shown in Fig. 2a.

The rate of photochemical decomposition, as well as the composition of the final products of this reaction, depend on the environment in which this process occurs. Laboratory studies have shown that after irradiation with UV radiation (A. = 254 nm) for 48 hours, up to 80% of DDT decomposes, and DDE (the main amount), DCD and ketones were found among the products. Further experiments showed that DDD is very resistant to UV radiation, and DDE is gradually converted into a number of compounds, among which PCBs were found. The metabolism of COS by microorganisms, based on their use of organic carbon as food, is almost always catalyzed by biological enzymes.

DDE sg! a-chooschOjo-

dnchlorobenzophenone

С1- С - С1 I n ddd a) b)

Rice. Fig. 2. Scheme of the proposed mechanism of (a) photochemical and (b) metabolic conversion of DDT.

As a result of rather complex successive chemical reactions, various metabolites are formed, which may turn out to be either harmless substances or more dangerous to living organisms than their predecessors. A common scheme for the metabolic transformation of DDT, which is also true in principle for other COS, is shown in Fig. 26 .

The need to introduce in each country standards for monitoring the content of inorganic and organic pollutants in drinking water is often determined by the characteristics of land use in the water basin, the nature of the water source (surface and groundwater) and the presence of toxic compounds of industrial origin in them. Therefore, it is necessary to take into account a number of different local geographic, socio-economic, industrial and nutritional factors. All this can cause a significant deviation of national standards from the values ​​recommended by WHO for concentrations of various toxicants.

Conclusion Thesis on the topic "Ecology", Izvekova, Tatyana Valerievna

Main results and conclusions

1. It has been established that the change in the content of organic compounds in the Uvodskoye reservoir over time tends to decrease, although the concentrations of oil products and volatile phenols are still significantly higher than the normalized values ​​up to 42 and 4 MPC.x. respectively.

2. It is shown that there is no decrease in the content of organic compounds as a result of the dilution process at successive stations (Rozhnovo, Mikshino, Ivankovo). The dilution phenomenon is typical only for phenols, and for oil products, chloroform and trichloroethylene, a clear increase in concentrations is noted, which is associated with additional sources of income (diffusion from silt water, surface runoff).

3. For the first time, the main sources and sinks of oil and phenol hydrocarbons in the reservoir were established from the balance equation, namely:

The main sources of oil hydrocarbons entering the Uvodskoye reservoir are the Volga-Uvod canal and the runoff of the Uvod River (approximately 50% each), atmospheric precipitation and melt water do not have a great effect on the content of oil products in the water of the reservoir;

For phenols, the main sources are all considered channels of entry: the Volga-Uvod canal - 36%, rain runoff - 26%, runoff of the river. Take away - 23%, melt water -15%;

The main excretion channels were determined: for phenols - hydrodynamic removal (~ 50%); for oil products - hydrodynamic removal, evaporation and biochemical transformation - 34, 30, 29%, respectively.

4. It is shown that the concentrations of COS in drinking water are interrelated both with the processes inside the reservoir and with the process of water disinfection - chlorination.

5. The total content of organochlorine compounds (in terms of SG) after chlorination of water from the Uvodsk reservoir increases on average 7 times, and after chlorination of water from an underground source (Gorinsky water intake) only 1.3 times.

6. A correlation has been established between the content of chlorophenols and suspended organic matter in the water of the Uvodsk reservoir and the concentrations of 2,4-dichlorophenol and 2,4,6-trichlorophenol after chlorination of drinking water.

7. The current state of drinking water consumed by the population of Ivanovo leads to a deterioration in his health and, as a result, a reduction in life expectancy (men - 5 years, women - 8 years, 2001). The amount of financial losses is estimated at 0.3 billion €/year, and based on the statistical cost of living, at 0.96 billion €/year.

8. It is shown that chlorophenols in the water of the Uvodskoe reservoir are mainly in the composition of suspended matter, therefore it is recommended to improve the process of its filtration in order to reduce their concentration in drinking water, as well as to carry out water intake from a controlled depth, especially in the spring and summer.

9. It was revealed that the main contribution to the value of the environmental risk value is made by chemical chemical agents, therefore it is recommended to replace the first stage of chlorination (ONVS-1) with ozonation.

Bibliography Thesis in biology, candidate of chemical sciences, Izvekova, Tatyana Valerievna, Ivanovo

1. Kuzubova L.I., Morozov C.V. Organic contaminants of drinking water: Analyte. Review / State Public Scientific and Technical Library of the Siberian Branch of the Russian Academy of Sciences, NIOCH of the Siberian Branch of the Russian Academy of Sciences. Novosibirsk, 1993. -167 p.

2. Isaeva L.K. Control of chemical and biological parameters of the environment. St. Petersburg: "Ecological and Analytical Information Center" Soyuz "", 1998.-869 p.

3. Randtke S.J. Organic contaminant removal by coagulation and related process combinations // JAWWA. 1988. - Vol. 80, No. 5. - P. 40 - 56.

4. Guidelines for drinking water quality control. T.1. Recommendations, WHO. -Geneva, 1986.- 125 p.

5. Warthington P. Organic micropollutants in the aqueous environment // Proc. 5 Int. Conf. "Chem. Prot. Environ." 1985. Leaven 9-13 Sept. 1985. Amsterdam, 1986.

6. Yudanova L.A. Pesticides in the environment. Novosibirsk: State Public Scientific and Technical Library of the Siberian Branch of the USSR Academy of Sciences, 1989.-140 p.

7. Elpiner L.I., Vasiliev B.C. Problems of drinking water supply in the USA. -M., 1984.

8. SanPiN 2.1.2.1074-01. Sanitary rules and norms "Drinking water. Hygienic requirements for water quality of centralized drinking water supply systems. Quality control.", approved by the State Committee for Sanitary and Epidemiological Supervision of Russia. M., 2000

9. Harmful substances in industry. 4.1. Ed. 6th, rev. L., Publishing house "Chemistry", 1971, 832 p.

10. Carcinogenic substances: Handbook / Per. from English / Ed. B.C. Turusov. M., 1987, 333 p.

11. Harmful chemicals. Hydrocarbons. Halogen derivatives of hydrocarbons. Right, ed. / Ed. V.A. Filova-L.: Chemistry, 1989.-732 p.

12. G. Fellenberg Environmental pollution. Introduction to environmental chemistry; Per. with him. M.: Mir, 1997. - 232 p.

Many types of waste water contain rotting substances, apart from some industrial waste water, which consists mainly of chemically toxic components. A rotting substance, such as meat or blood, is organic in nature and subject to the universal law of nature - decomposition, leading ultimately to mineralization. Since, as in the case of meat decay described above, the decomposition process is stimulated and maintained by autolytic enzymes, much of the above is true of both wastewater and meat. The difference, which should be noted already in view of the unequal concentration of the substance subject to decay - in the first case, compact meat, and in the second - an emulsion, etc., does not apply to the nature of the decomposition process, even if the latter occur in the wastewater of recycling enterprises where before in total, heat treatment is carried out by the physical action of superheated steam (decomposition by boiling). Part of the spore-forming microorganisms survive during sterilization and are also included in the decomposition process. In this case, there is a percentage decrease in biochemical oxygen demand.

In contrast to the efforts that are made at a certain point in time to interrupt the decomposition process of the raw materials of the recycling enterprises in order to preserve the feed, all efforts in wastewater treatment are aimed at achieving, by means of oxygen supply, a rapid and complete mineralization of organic components. If the mineralization process is inhibited, for example by an increased fat content in the waste water, this undesirable preservation-like effect must be counteracted with particular vigor (Randolph, 1977).

Wastewater treatment is essentially sedimentation with the formation of putrefactive sludge, as well as the decomposing activity of microorganisms during aerobiosis (activated sludge). Putrefactive sludge during anaerobiosis, being exposed to the action of microorganisms, is dehydrated, while activated sludge flakes support all the biological processes of wastewater treatment. no human effort ( methane tank, sedimentation, Emscher well), then to maintain aerobiosis for a long time, on the contrary, complex technical structures are needed (biofilters, oxidation ponds, activating circuits, cascades).

The supply of oxygen is an important prerequisite for the multiplication of microbes that break down the organic matter contained in wastewater. Moreover, the number of microbes decreases (the desire for anaerobiosis), if the used oxygen is not constantly and regularly replaced by a new one (bacteria and fungi are C-heterotrophic). This is the basis of their ability to break down organic matter. This function of microbes is an important part of the ecological system, within which wastewater and its treatment, as well as the biological self-cleaning of rivers and lakes, should be considered. Bacteria in natural water bodies and wastewater are “satisfied” with insignificant concentrations of nutrients. 39 out of 47 families of bacteria have their representatives in the microflora of water bodies and wastewater (Reinheimer, 1975). Fungi are also found here, which also absorb organic matter, since they are C-heterotrophic. Most fungi also need free oxygen. Mushrooms are characterized by a high pH tolerance and often a relatively large range of temperatures at which they can exist (pH 3.2-9.6; temperature 1-33°C). Mushrooms break down protein, sugar, fat, starch, pectins, hemicellulose, cellulose, chitin and lignin. The number of saprophytes in relation to the total number of microbes in heavily polluted water intakes ranges from 1:5 to 1:100, while in oligotrophic water bodies this figure varies between 1:100 and 1:1000. Waste water temperature and its protein saturation have a strong influence on the period of regeneration of heterotrophic bacteria and on the composition of the microbial flora. First, saprophytes appear in the wastewater, then microbes that break down cellulose, and finally nitrifying bacteria, which are represented in the largest number. Each milliliter of domestic wastewater can contain between 3 and 16 million bacteria, including tens or even hundreds of thousands of coli bacteria. Such wastewater contains a wide range of Enterobacteriacetae. Polluted wastewater, rich in organic matter, is easily enriched with chlamydobacteria, especially Sphaerotilus natans, which can subsequently lead to a phenomenon called fungal forcing. Saprophytes differ from pathogenic microbes, in particular, in that the former break down only inanimate organic matter, while the latter also decompose living tissues. In this case, pathogens prepare the field of activity for saprophytes, destroying living tissues in whole or in part. Biochemical oxygen demand (BOD) is the amount of oxygen that microorganisms of the mentioned species need to break down harmful organic substances in wastewater from both recycling and other enterprises. It is clear that the increased need of microorganisms for oxygen indicates the contamination of wastewater. By measuring biochemical oxygen demand over a five-day period (BODb), it is possible to determine or approximately estimate both the degree of contamination of wastewater with harmful organic substances and the quality of the functioning of the treatment system itself. Data obtained in this way can be supplemented by determining the chemical oxygen demand of substances, data on the amount of precipitated substances, and their ability to decay. It is advisable to always determine the pH value and, if necessary, also the number and type of the most widely represented bacteria (see page 193 et ​​seq.).

DONETSK NATIONAL UNIVERSITY

CHEMICAL FACULTY

DEPARTMENT OF ORGANIC CHEMISTRY

Introduction…………………………………………………………...3

Literature review. Classification and properties

wastewater…………………………………………………..……5

The physical state of wastewater……………………….....….8

Wastewater composition……………………………………………………………………………………………………………………………………………………………………..10 Bacterial pollution of waste water………………………....11

A reservoir as a wastewater receiver……………………………..11

EPS cleaning methods…………………………………………………………………………………………12

Mechanical cleaning of PSV……………………………………..13

Physical and chemical cleaning of PSV………………………………………………14

Chemical analysis of PSV………………………………………..16

Determination of organic substances

chromatography method……………………………….………..18

Determination of organic compounds

mass spectrometry method………………………….……….19

Chemical test methods of analysis……………………………….20

Practical part.

Gas Chromatography Method……………………………..24

Mass spectroscopy method………………………………………..26

Conclusions …………...……………………………………………...27

References……………………………………..28

Introduction

Water is the most valuable natural resource. It plays an exceptional role in the metabolic processes that form the basis of life. Water is of great importance in industrial and agricultural production. It is well known that it is necessary for the everyday needs of man, all plants and animals. For many living beings, it serves as a habitat. The growth of cities, the rapid development of industry, the intensification of agriculture, the significant expansion of irrigated land, the improvement of cultural and living conditions, and a number of other factors are increasingly complicating the problems of water supply.

The demand for water is enormous and is increasing every year. The annual consumption of water on the globe for all types of water supply is 3300-3500 km3. At the same time, 70% of all water consumption is used in agriculture. A lot of water is consumed by the chemical and pulp and paper industries, ferrous and non-ferrous metallurgy. Energy development also leads to a sharp increase in demand for water. A significant amount of water is consumed for the needs of the livestock industry, as well as for the domestic needs of the population. Most of the water after its use for household needs is returned to the rivers in the form of wastewater.

Fresh water scarcity is already becoming a global problem. The ever-increasing needs of industry and agriculture for water are forcing all countries, scientists of the world to look for various means to solve this problem.

At the present stage, the following areas of rational use of water resources are determined: more complete use and expanded reproduction of fresh water resources; development of new technological processes to prevent pollution of water bodies and minimize the consumption of fresh water.

The rapid development of industry makes it necessary to prevent the negative impact of industrial wastewater (ISW) on water bodies. Due to the extreme diversity of the composition, properties and flow rates of wastewater from industrial enterprises, it is necessary to use specific methods, as well as facilities for local, preliminary and complete treatment of these waters. One of the main directions of scientific and technological progress is the creation of low-waste and waste-free technological processes.

The purpose of the work is to get acquainted with the literature data on wastewater treatment methods.

Literature review
1.1.Classification and properties of wastewater
Contaminated wastewater of mineral, organic and bacterial origin enters the sewerage network.

Mineral contaminants include: sand; clay particles; particles of ore and slag; salts, acids, alkalis and other substances dissolved in water.

Organic contaminants are of plant and animal origin. To vegetable include the remains of plants, fruits, vegetables and cereals, paper, vegetable oils, humic substances and more. The main chemical element that is part of these pollution is carbon. To pollution of animal origin include physiological secretions of animals and humans, the remains of animal muscle and fat tissues, organic acids, and more. The main chemical element of these pollutions is nitrogen. Domestic water contains approximately 60% of organic pollution and 40% of mineral. In PSV, these ratios may be different and vary depending on the type of processed raw materials and the production process.

to bacterial contamination include living microorganisms - yeast and mold fungi and various bacteria. Domestic wastewater contains such pathogenic bacteria (pathogenic) - pathogens of typhoid fever, paratyphoid, dysentery, anthrax, etc., as well as helminth eggs (worms) that enter wastewater with human and animal secretions. Pathogens are also contained in some PSV. For example, in wastewater from tanneries, wool primary processing factories, etc.

Depending on the origin, composition and quality characteristics of pollution (impurities), wastewater is divided into 3 main categories: domestic (household and fecal), industrial (industrial) and atmospheric.
Domestic wastewater includes water removed from toilets, baths, showers, kitchens, baths, laundries, canteens, hospitals. They are polluted mainly with physiological waste and household waste.
Industrial wastewater is water used in various technological processes (for example, for washing raw materials and finished products, cooling thermal units, etc.), as well as water pumped to the surface of the earth during mining. Industrial wastewater from a number of industries is polluted mainly by production waste, which may contain toxic substances (for example, hydrocyanic acid, phenol, arsenic compounds, aniline, copper, lead, mercury salts, etc.), as well as substances containing radioactive elements; some wastes are of a certain value (as secondary raw materials). Depending on the amount of impurities, industrial wastewater is divided into polluted, subjected to preliminary treatment before being released into the reservoir (or before reuse), and conditionally clean (slightly polluted), released into the reservoir (or reused in production) without treatment.
Atmospheric waste water - rain and melt (formed as a result of melting ice and snow) water. According to the qualitative characteristics of pollution, this category also includes water from watering streets and green spaces. Atmospheric wastewater containing predominantly mineral contaminants is less hazardous in sanitary terms than domestic and industrial wastewater.
The degree of pollution of wastewater is estimated by the concentration of impurities, i.e. their mass per unit volume (in mg/l or g/m3).
The composition of domestic wastewater is more or less uniform; the concentration of contaminants in them depends on the amount of tap water consumed (per inhabitant), i.e., on the rate of water consumption. Domestic wastewater pollution is usually classified into: insoluble, forming large suspensions (in which particle sizes exceed 0.1 mm) or suspensions, emulsions and foams (in which particle sizes range from 0.1 mm to 0.1 μm), colloidal ( with particles ranging in size from 0.1 μm to 1 nm), soluble (in the form of molecularly dispersed particles with a size of less than 1 nm).
There are pollution of domestic wastewater: mineral, organic and biological. Mineral contaminants include sand, slag particles, clay particles, solutions of mineral salts, acids, alkalis, and many other substances. Organic contaminants are of plant and animal origin. Plant residues include the remains of plants, fruits, vegetables, paper, vegetable oils, etc. The main chemical element of plant pollution is carbon.
Contaminants of animal origin are physiological excretions of people and animals, remains of animal tissues, adhesive substances, etc. They are characterized by a significant nitrogen content. Biological contaminants include various microorganisms, yeasts and molds, small algae, bacteria, including pathogens (causative agents of typhoid, paratyphoid, dysentery, anthrax, etc.). This type of pollution is characteristic not only of domestic wastewater, but also of some types of industrial wastewater generated, for example, in meat processing plants, slaughterhouses, tanneries, biofactories, etc. According to their chemical composition, they are organic contaminants, but they are separated into a separate group due to the sanitary hazard they create when they enter water bodies.
In domestic wastewater, mineral substances contain about 42% (of the total amount of pollution), organic - about 58%; sedimented suspended solids make up 20%, suspensions - 20%, colloids - 10%, soluble substances - 50%.
The composition and degree of contamination of industrial wastewater are very diverse and depend mainly on the nature of production and the conditions for using water in technological processes.
The amount of atmospheric water varies significantly depending on climatic conditions, terrain, the nature of urban development, the type of road surface, etc. 1 ha. The annual runoff of rainwater from built-up areas is 7-15 times less than domestic.

1.2 Physical state of wastewater
The physical state of wastewater is of three types:

undissolved appearance;

colloidal appearance;

dissolved look.

undissolved substances are found in wastewater in the form of a coarse suspension with a particle size of more than 100 microns and in the form of a fine suspension (emulsion) with a particle size of 100 to 0.1 microns. Studies show that in domestic wastewater the amount of undissolved suspended solids remains more or less constant and is equal to 65g/day per person using the sewer; of these, 40g can precipitate during settling.

Colloidal substances in water have particle sizes ranging from 0.1 to 0.001 microns. The composition of the colloidal phase of domestic wastewater is influenced by its organic components - proteins, fats and carbohydrates, as well as the products of their physiological treatment. The quality of tap water, which contains a certain amount of carbonates, sulfates and iron, also has a great influence.

In addition to nitrogen and carbon, wastewater also contains a large amount of sulfur, phosphorus, potassium, sodium, chlorine and iron. These chemical elements are part of organic or mineral substances that are in wastewater in an undissolved, colloidal or dissolved state. The amount of these substances introduced with pollution into wastewater can be different and depends on the nature of the formation.

However, for domestic wastewater, the amount of chemicals introduced with pollution per person remains more or less constant. So, per person per day account for (g):

Table 1. Chemicals Contributed by Pollution per Person

The concentration of these substances in wastewater (mg / l) varies depending on the degree of dilution of contaminants with water: the higher the rate of water disposal, the lower the concentration. The content of iron and sulfates in wastewater depends mainly on their presence in tap water.

The amount of the above, as well as other ingredients that enter the IWW with pollution, varies greatly and depends not only on their content in the diluted tap water and the processed product, but also on the production process, the mode of water entering the production network and other reasons. Therefore, for a given type of production, it is possible to establish only an approximate amount of contaminants contained in discharged EPS. When designing industrial sewerage, it is necessary to have data from the analysis of PSV, and only if such data cannot be obtained, data from similar industries can be used.

1. 
   Waste water composition

The composition and quantity of PSV are different. Even enterprises of the same type, such as tanneries, depending on the nature of the technological process, can discharge wastewater of different composition and in different quantities.

Some EPS contain no more than household contaminants, but others significantly more. Thus, water from ore processing plants contains up to 25,000 mg/l of suspended particles, from wool washing plants - up to 20,000 mg/l.

EPS are divided into conditionally clean and contaminated. Conditionally pure waters are more often those that were used for cooling; they almost do not change, but only heat up.

Contaminated industrial waters are divided into groups containing certain contaminants: a) predominantly mineral; b) predominantly organic, mineral; c) organic, toxic substances.

EPS, depending on the concentration of contaminants, can be highly concentrated and weakly concentrated. Depending on the active reaction of water, industrial waters are divided into slightly aggressive waters (slightly acidic with pH = 6–6.6 and slightly alkaline with pH = 8–9) and highly aggressive (with pH 9) according to the degree of aggressiveness.

1. 
   Bacterial pollution of sewage

Flora and fauna of wastewater are represented by bacteria, viruses, bacteriophages, helminths and fungi. There is a huge amount of bacteria in the waste liquid: there can be up to 1 billion of them in 1 ml of waste water.

Most of these bacteria belong to the category of harmless (saprophytic bacteria) that multiply on a dead organic medium, but there are also those that multiply and live on living matter (pathogenic bacteria), destroying a living organism in the course of their life. Pathogenic microorganisms found in urban wastewater are pathogens of typhoid, paratyphoid, dysentery, water fever, tularemia, etc.

The presence of a special type of bacteria in it - a group of Escherichia coli - indicates the contamination of water with pathogenic bacteria. These bacteria are not pathogenic, but their presence indicates that pathogenic bacteria may also be present in the water. To assess the degree of contamination of water with pathogenic bacteria, determine if - titer, i.e. the smallest amount of water per ml that contains one Escherichia coli. So, if the titer of Escherichia coli is 100, then this means that 10 ml of the studied water contains one Escherichia coli. With a titer of 0.1, the number of bacteria in 1 ml is 10, and so on. For urban wastewater, the titer of Escherichia coli usually does not exceed 0.000001. Sometimes they determine if - an index, or the number of E. coli in 1 liter of water.

1. 
   Water body as a wastewater receiver

Most of the waste water is received by water bodies. Waste water must be partially or completely cleaned before being discharged into the reservoir. However, there is a certain supply of oxygen in the reservoir, which can be partially used for the oxidation of organic matter that enters it together with wastewater; the reservoir has some cleansing ability, i.e. in it, with the help of microorganisms - mineralizers, organic substances can be oxidized, but the content of dissolved oxygen in the water will fall. Knowing this, it is possible to reduce the degree of wastewater treatment at treatment facilities before discharging them into a reservoir.

One should not exaggerate the ability of water bodies, in particular rivers, to receive large masses of wastewater, even if the oxygen balance allows such a discharge without final treatment. Any, even a small, body of water is used for mass bathing and has architectural, decorative and sanitary significance.

1. 
   EPS cleaning methods

PSVs are usually divided into 3 main groups:

1. 
   Pure water, usually used for cooling;
2. 
   Slightly polluted, or conditionally clean, water generated from the washing of finished products;
3. 
   Dirty waters.

Clean and low-polluted waters can be sent to the water recycling system or used to dilute polluted waters to reduce the concentration of pollution. Often, separate discharge of PSV and separate purification of these waters by one or another method are used before descending into the reservoir. This is justified economically.

The following methods are used to clean the PSV:

1. 
   mechanical cleaning.
2. 
   Physical and chemical cleaning.
3. 
   Chemical cleaning.
4. 
   Biological cleaning.

When they are used together, the method of purification and disposal of wastewater is called combined. The use of a particular method in each specific case is determined by the nature of the pollution and the degree of harmfulness of impurities.
1.6.1. Mechanical cleaning of PSV
Mechanical purification of PSV is intended to isolate undissolved and partially colloidal impurities from them. Mechanical cleaning methods include: a) filtering; b) upholding; c) filtering; d) removal of undissolved impurities in hydrocyclones and centrifuges.

Straining used to isolate large floating substances and smaller, mainly fibrous contaminants from the waste liquid. Grids are used to separate large substances, and sieves are used for smaller ones. Grids for pre-cleaning must be arranged for all sewage treatment plants. Sieves are used as independent devices, after passing through which PSV can be dumped either into a reservoir or into the city sewer network.

by settling undissolved and partially colloidal contaminants of mineral and organic origin are isolated from PSV. By settling, it is possible to separate from wastewater both particles with a specific gravity greater than the specific gravity of water (sinking), and with a lower specific gravity (floating). Settling tanks for IWW treatment can be independent facilities, where the treatment process ends, or facilities intended only for preliminary treatment. To isolate sinking insoluble impurities, both horizontal and radial settling tanks are used; in their design, they differ little from the settling tanks used to clarify domestic wastewater.

Filtration serves to retain suspended matter that has not settled during settling. Sand filters, diatomite filters and mesh filters with a filter layer are used.

Sand filters used for low solids content. Two-layer filters have proven themselves well. The bottom layer of the load is sandy with a grain size of 1-2 mm, and the top layer is anthracite chips. Waste water is supplied from above, then wash water is supplied and dirty water is discharged.

diatomaceous earth filters. In these filters, the waste liquid is filtered through a thin layer of diatomaceous earth applied to porous surfaces. Ceramics, metal mesh and fabric are used as porous materials. Artificial powder compositions of diatomite with high adsorption capacity are also used. Such filters provide a high cleaning effect.

Hydrocyclones used for clarification of wastewater and thickening of sediment. They are open and pushy. Open hydrocyclones are used to isolate structural settling and coarse floating impurities from wastewater. Pressure hydrocyclones are used to separate from wastewater only settling aggregate-resistant coarse structural impurities. Open hydrocyclones are available without internal devices, with a diaphragm and a cylindrical baffle, and are multi-tiered. The latter are used to isolate heavy non-caking coarse impurities and oil products.
1.6.2. Physical and chemical cleaning of PSV

Physical and chemical cleaning methods include: a) extraction; b) sorption; c) crystallization; d) flotation.

A) extraction. The essence of the extraction method for industrial wastewater treatment is as follows. When mutually insoluble liquids are mixed, the contaminants contained in them are distributed in these liquids according to their solubility.

If the wastewater contains phenol, the water can be mixed with benzene (a solvent), in which the phenol dissolves to a much greater extent, to isolate it. Thus, by successively acting benzene on water, it is possible to achieve almost complete removal of phenol from water.

Various organic substances are usually used as solvents: benzene, carbon tetrachloride, etc.

Extraction is carried out in metal tanks-extractors having the form of columns with nozzles. A solvent is supplied from below, the specific gravity of which is less than the specific gravity of water, as a result of which the solvent rises up. Polluted wastewater is fed from above. Layers of water, meeting a solvent on their way, gradually give off water pollutants. Purified water is discharged from below. This technique, in particular, can be used to purify PSV containing phenol.

B) Sorption. This process consists in the fact that contaminants from the waste liquid are absorbed by the solid body (adsorption), deposited on its actively developed surface (adsorption) or enter into chemical interaction with it (chemisorption). Adsorption is most often used to purify the PSV. In this case, a crushed sorbent (solid body) is added to the waste liquid to be treated and mixed with waste water. Then the sorbent saturated with contaminants is separated from the water by sedimentation or filtration. More often, treated waste water is passed continuously through a filter loaded with a sorbent. The following are used as sorbents: activated carbon, coke breeze, peat, kaolin, sawdust, ash, etc. The best, but most expensive substance is activated carbon.

The sorption method can be used, for example, for the purification of IWW from gas generating stations containing phenol, as well as IWW containing arsenic, hydrogen sulfide, etc.

c) Crystallization. This cleaning method can only be used if the concentration of contaminants in the EPS is significant and their ability to form crystals. Usually the preliminary process is the evaporation of the waste water in order to create an increased concentration of contaminants, at which their crystallization is possible. To speed up the process of crystallization of contaminants, the waste water is cooled and mixed. Evaporation and crystallization of waste water are usually carried out in natural ponds and reservoirs. This method of purification of PSV is uneconomical, therefore it has not been widely used.

D) flotation. The process is based on the floating of dispersed particles together with air bubbles. It is successfully used in a number of branches of technology and for the purification of PSV. The flotation process consists in the fact that molecules of insoluble particles stick to air bubbles and float together to the surface. The success of flotation largely depends on the size of the surface of the air bubbles and on the area of ​​their contact with solid particles. To increase the effect of flotation, reagents are introduced into the water.
1.6.3 Chemical analysis of EPS
The composition of wastewater, even of good quality, is often difficult to predict. First of all, this applies to wastewater after chemical and biochemical treatment, as a result of which new chemical compounds are formed. Therefore, as a rule, the suitability of even fairly well-proven methods for the determination of individual components and analysis schemes should be checked beforehand.

The main requirements for wastewater analysis methods are high selectivity, otherwise systematic errors may occur that completely distort the result of the study. Of less importance is the sensitivity of the analysis, since it is possible to take large volumes of analyzed water or resort to a suitable method of concentrating the analyte.

To concentrate the components to be determined in wastewater, extraction, evaporation, distillation, sorption, coprecipitation, and freezing of water are used.

Table 2. Schemes for the separation of wastewater components with a high content of volatile organic substances.

Option 1	The sample is acidified with H 2 SO 4 to a slightly acidic reaction, distilled off with water vapor until a small residue is obtained.
	Distillate 1: volatile acids and neutrals Alkaline and again distilled off with water vapor until a small residue is obtained.	Residue 1: non-volatile acids, amine sulfates, phenols and neutrals
		Residue 2: sodium salts of volatile acids, phenols
Option 2	The sample is alkalized and distilled off with water vapor until a small residue is obtained.
	Distillate 1: volatile bases and neutrals	Residue 1: salts of volatile and non-volatile acids
	Acidified and distilled off with steam until a small residue is obtained.
	Distillate 2: volatile neutral compounds	Residue 2: salts of volatile bases. Stir and extract with ether

Table 3. Scheme for the separation of wastewater components with a low content of volatile organic substances

To a sample (25-100 ml) of waste water is added until NaCl and HCl are saturated to a concentration of ≈ 5%
Extracted with diethyl ether
Extract 1: neutral compounds, acids. Treated three times with 5% NaOH solution			Aqueous phase1: add NaOH until pH ≥ 10, extract several times with ether, combine extracts
Aqueous phase 2: weak acids (mainly phenols). Saturate with CO 2 until NaHCO 3 precipitates, treat with several portions of ether, extracts are combined	Ether layer: neutral substances. Dry dry. Na 2 SO 4 , the ether is distilled off, the dry residue is weighed, dissolved in ether, transferred to a silica gel column. Elute successively with aliphatic isooctane, aromatic benzene. The solvent is evaporated from each eluate, the residue is weighed.		Aqueous phase 3: amphoteric non-volatile compounds, soluble in water better: than in ether. Neutralize CH 3 COOH, extract with several portions of ether, combine the extracts	Ether layer: basic compounds. Dry with Na 2 SO 4 , distill off the ether, weigh the dry residue
The ether layer is dried anhydrous. Na 2 SO 4, the ether is distilled off, the dry residue is weighed	water phase. Ether is removed, acidified, treated with several portions of ether		Combined extracts: amphoteric substances. Dry with Na 2 SO 4 , distill off the ether, weigh the dry residue.	water phase. Acidified to pH 3-4, evaporated to dryness. Residue suitable for carbon determination
	The ethereal layer is dried with Na 2 SO 4 , the ether is distilled off. The rest is weighed.	The aqueous phase is discarded

1.6.3.1 Determination of organic substances by chromatography
Gasoline, kerosene, fuel and lubricating oils, benzene, toluene, fatty acids, phenols, pesticides, synthetic detergents, organometallic and other organic compounds get into surface water from runoff. Organic matter in wastewater samples taken for analysis is easily altered by chemical and biochemical processes, so the collected samples should be analyzed as soon as possible. In table. Figures 2 and 3 show the schemes for the separation of organic substances present in wastewater.

Various chromatographic methods are widely used for identification and quantification - gas, column, liquid chromatography, paper chromatography, thin layer chromatography. For quantitative determination, gas chromatography is the most suitable method.

As an example, consider the definition of phenols. These compounds are formed or used in the process of oil refining, paper production, dyes, drugs, photographic materials and synthetic resins. The physical and chemical properties of phenols make it relatively easy to determine them by gas chromatography.
1.6.3.2 Determination of organic compounds by mass spectrometry
In the analysis of wastewater, the capabilities of mass spectrometry are especially important in terms of identifying compounds of unknown structure and analyzing complex mixtures, determining microcomponents against the background of accompanying substances, the concentration of which is orders of magnitude higher than the concentrations of the components being determined. GLC with MS, tandem MS, a combination of HPLC and MS for the analysis of non-volatiles, as well as "soft ionization" and selective ionization methods are suitable here.

Residual quantities of octylphenol polyethoxylates in wastewater, their biodegradation and chlorination products formed during the biological treatment and disinfection of wastewater can be determined by GLC-MS with EI or chemical ionization.

The need to analyze compounds of different volatility was reflected in the scheme for the analysis of trace amounts of organic compounds contained in wastewater after treatment at a treatment plant. Here, GLC was used for quantitative determinations, and qualitative analysis was carried out using GC-MS. Highly volatile compounds - halocarbons C 1 - C 2 were extracted with pentane from 50 ml of a water sample; 5 µl of the extract was injected into a 2mx4 mm column with 10% squalane on Chromosorb W-AW at 67°C; carrier gas - a mixture of argon and methane; electron capture detector with 63 Ni. If it was necessary to determine methylene chloride, then the pentane eluting with it was replaced by octane, which eluted later. 1,2 dibromoethane was used as an internal standard. The aromatic hydrocarbon group was determined using headspace analysis in a closed loop.

The combination of different ionization methods makes it possible to more reliably identify the various components of wastewater pollution. For the general characterization of organic substances present in wastewater and sewage sludge, a combination of GC and MS with EI and CI ionization is used. Organic compounds extractable from wastewater with hexane were chromatographed on silica gel, eluting with hexane, methylene chloride, and ether. The resulting fractions were analyzed on a system consisting of a gas chromatograph with a capillary tube 25 m long, connected to an ion source of a double-focusing mass spectrometer. The column temperature was programmed from 40 to 250°C at a rate of 8°C/min. 66 compounds were identified by gas chromatographic retention times and EI and CI mass spectra. Among these compounds were halogenated methoxybenzenes, dichlorobenzene, hexachlorobenzene, methylated triclosan, oxadiazon, etc. This method also made it possible to give a semi-quantitative assessment of the concentrations of these compounds.
1.6.3.3 Chemical test methods of analysis
HNU Systems Inc. They produce test kits for the determination of crude oil, combustible fuels, waste oil in soil and water. The method is based on Friedel-Crafts alkylation of aromatic hydrocarbons found in petroleum products with alkyl halides to form colored products:

Anhydrous aluminum chloride is used as a catalyst. When analyzing water, extraction is carried out from 500 ml of the sample. Depending on the component being determined, the following colors of the extract appear:

• 
  Benzene - from yellow to orange;
• 
  Toluene, ethylbenzene, xylene - from yellow-orange to bright orange;
• 
  Gasoline - from beige to red-brown;
• 
  Diesel fuel - from beige to green.

Color scales are drawn up for water in the ranges of 0.1 - 1 - 5 - 10 - 20 - 50 - 100 mg/l.

In the test analysis, phenol and its derivatives are mainly determined by the formation of an azo dye. The most common is the following method: the first stage is the diazotization of the primary aromatic amine with sodium nitrite in an acidic medium, leading to the formation of a diazonium salt:
ArNH 2 + NaNO 2 + 2HCl → + Cl ¯ + NaCl + 2H 2 O,
The second stage is the combination of a diazonium salt with phenols in an alkaline medium, leading to the formation of an azo compound:
+ Cl ¯ + Ph–OH → ArN=N–Ph–OH + HCl
If the pair position is closed, then formed about- azo compound:

Azo coupling with hydroxy compounds, the most active in the form of phenolate anions, is almost always carried out at pH 8–11. Diazonium salts

In an aqueous solution, they are unstable and gradually decompose into phenols and nitrogen; therefore, the main difficulty in creating test methods for the determination of phenols and amines lies precisely in obtaining stable diazo compounds.

As a storage-stable reagent for the determination of phenol, a complex salt of 4-nitrophenyldiazonium tetrafluoroborate (NDF) has been proposed:
O 2 N–Ph–NH 2 + BF 4 → BF 4
To determine phenol, 1 square of filter paper impregnated with NDP and 1 square of paper impregnated with a mixture of sodium carbonate and cetylpyridinium chloride (CP) are added to 1 ml of the analyzed liquid.

In the presence of CP, the color deepens due to the formation of an ion associate at the dissociated hydroxy group:
O 2 N–Ph–N≡N + + Ph–OH → O 2 N–Ph–N=N–Ph–OH

O 2 N–Ph–N=N–Ph–O ¯ CPU +
The determination of phenol does not interfere with 50-fold amounts of aniline. Do not interfere with the determination of 2,4,6-substituted phenol, 2,4-substituted 1-naphthol and 1-substituted 2-naphthol. Ranges of determined contents for phenol: 0.05 - 0.1 - 0.3 - 0.5 - 1 - 3 - 5 mg/l. The developed tests were used to determine phenol in wastewater.

Most of the test methods use 4-aminoantipyrine as a reagent. Phenol and its homologues with 4-aminoantipyrine form colored compounds in the presence of hexacyanoferate (III) at pH 10:

Practically do not react with 4-aminoantipyrine n-cresol and those para-substituted phenols in which the substituent groups are alkyl-, benzoyl-, nitro-, nitroso- and aldehyde groups. The range of determined contents for NANOCOLOR ® Phenol systems, Hach Co., CHEMetrics is 0.1 – 5.0 mg/l of phenol.

2. Practical part
2.1 Theoretical foundations of quality control methods for cleaning IWW
To control the quality of IWW cleaning, it is necessary to create special laboratories, for example, an industrial sanitation laboratory.

Since the composition of IWW is quite diverse, it is necessary to constantly monitor the quality of purification of these waters.

Let us consider some methods for the determination of organic compounds in natural wastewater.
2.1.1 Gas chromatography method
We analyze phenol and its derivatives.

The analyzed waste water is diluted with an equal volume of 1 M sodium hydroxide solution, extracted with a mixture of 1: 1 diethyl and petroleum ether to separate all other organic substances contained in the waste water from the sodium salts of phenols remaining in the aqueous phase. The aqueous phase is separated, acidified and injected into a gas chromatograph. More often, however, phenols are extracted with benzene and the resulting benzene extract is chromatographed. Both phenols and their methyl esters can be chromatographed. The figure shows a gas chromatogram of a benzene extract of a mixture of phenols obtained on a glass column 180 cm long with an outer diameter of 6 mm, filled with a liquid carbohydrate phase of the apieson L type. 70 ml/min. A flame ionization detector was used. Under these conditions, the separation of the peaks in the chromatogram is sufficiently clear, and it is possible to quantify about- and P-chlorophenols, phenol and m-cresol.

To determine a small amount of organic compounds, it is necessary to preconcentrate them by sorption on active carbon. Depending on the content of organic compounds, it may take from 10 - 20 g to 1.5 kg of coal. After passing the analyzed water through specially purified substances, it must be desorbed. To do this, the charcoal is dried on a copper or glass tray in an atmosphere of clean air, the dried charcoal is placed in a paper cartridge covered with glass wool, and desorbed with a suitable solvent in a Soxhlet apparatus for 36 or more hours.

No single pure solvent is capable of extracting all sorbed organic substances, so one has to resort to sequential treatment with several solvents or use mixtures of solvents. The most satisfactory recovery of sorbed organic substances is achieved by using a mixture of 47% 1,2-dichloropropanol and 53% methanol.

After extraction, the solvent is distilled off, the residue is dissolved in chloroform. If an insoluble residue remains, it is dissolved in acetic acid, evaporated and the dry residue is weighed. The chloroform solution is dissolved in ether and then the analysis is given in table. 3.
R is. Fig. 4. Gas chromatogram of a benzene extract of a mixture of phenols from a waste water sample: 1 – o-chlorophenol; 2 - phenol; 3 - m-cresol; 4 - p-chlorophenol.
2.1.2 Mass spectroscopy method

The sample was placed in the extractor, an internal standard was added, covered with an activated carbon filter, and the vapor phase was blown through the filter for 30 s to remove impurities from the air. After that, a clean filter was placed and the flow rate was set to 1.5 l/min. After 2 hours, the filter was removed and extracted with three 7 µl portions of CS 2 and analyzed by capillary GLC with a flame ionization detector. Chlorinated hydrocarbons, pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons were extracted with hexane 2 × 15 ml in 1 l of water sample. The phases were separated after settling for at least 6 h. The extracts were dried, concentrated to 1 ml in a stream of nitrogen, and purified on a floricium column. Chlorinated hydrocarbons, pesticides and biphenyls were eluted with 70 ml of a mixture of hexane and ether (85:15) and concentrated to 1 ml. The concentrate was analyzed on a 50 m long glass capillary column with SE-54 with an electron capture detector; unknown compounds were identified using GC–MS.

Chlorinated paraffin hydrocarbons in sludge, sediments, and other environmental objects were determined by treating samples with sulfuric acid and separating them into fractions with minimal contamination by other compounds using adsorption chromatography on Al 2 O 3 . These fractions in hexane solution were injected into a 13 m x 0.30 mm SE-54 chromatographic column. The initial temperature of the column was 60°C; after 1 min, the temperature began to increase at a rate of 10°C/min to 290°C. Full mass spectra were recorded in the mass range from 100 to 600 amu. e. m. every 2s. The limit of detection was 5 ng, which corresponded to a relative concentration of 10 -9 .
conclusions
The development of environmental structures cannot be carried out without an appropriate environmental justification. The basis of such a justification is the assessment of the impact of treated wastewater on water intakes. The need to carry out work to assess the state of reservoirs and watercourses was formulated at the end of the century before last.

Systematic analyzes of the quality of purified and river water were started in 1903 by the laboratory of Professor V. R. Williams at the Agricultural Academy.

In the chemical industry, a wider introduction of low-waste and non-waste technological processes, which give the greatest environmental effect, is planned. Much attention is paid to improving the efficiency of industrial wastewater treatment.

It is possible to significantly reduce the pollution of water discharged by an enterprise by separating valuable impurities from wastewater; the complexity of solving these problems at chemical industry enterprises lies in the variety of technological processes and products obtained. It should also be noted that the main amount of water in the industry is spent on cooling. The transition from water cooling to air cooling will reduce water consumption by 70-90% in various industries.

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Yes, that's right: water is an organic substance and in this sense it is the basis of everything. living on earth. More aphoristically speaking, water is life, and notfiguratively, but literally.

Let me start with a simple statement: science tells us that the entire organic world is including both plants and animals, are 80-90% water, and all processesthey occur again with the direct participation of the same water. This alonethe fact, as it were, tells us that water itself must be organic matterIn this regard, I will immediately highlight that extremely important and at the same timejust as simple and recognized by all, without exception, the fact that birth is allorganisms of our planet is inextricably linked with water. I would even put it this way:- this is a specially transformed and organized water.

Indeed, one does not need to be seven spans in the forehead to see that for any living organism, water is not only an indispensable, but also the main componentcomponent. Its quantity in living organisms, with the possible exception ofranges from 70 to 99.7% by weight. From this fact alone, not to mention the othereven more significant, it is obvious that water plays not only a big rolethe vital activity of organisms, as everyone without exception recognizes, and the roledecisive, decisive, fundamental. But to play such a role,must itself be organic matter.

Strange, however, it turns out a thing: in principle, no one disputes the primary role of water in the life of all living beings without exception, and yetblatant contradiction to such a role is also recognized by all chemicallythe composition of water, expressed by the formula H2O. But by doing so, voluntarily or involuntarilya completely absurd fact is recognized, namely, that water is this unconditional foundationall organic life—itself is inorganic matter, in other words,dead substance

Hence, from the very beginning, a tough alternative suggests itself: either erroneous idea of ​​water as the basis of all living things, or erroneouscurrent understanding of the chemical composition of water. The first "either"immediately discarded as having no soil under it. Remains second"either", namely that the formula for water H2O is wrong. No third optionIn this case, it is not given, and it cannot be in principle. And here it is already a priori, i.e.before any experience, there is every reason to assert that water itself is a substanceorganic. It is this (and only this!) quality that can make it the basis of allalive. And no matter what arguments against this the current well-fedrelaxed science, these arguments are also a priori, that is, obviously, areerroneous. Only then can the questionBefore turning to this main issue, I would like to draw attention toanother remarkable fact in all respects, which, as we shall see,further, is directly related to water. The fact is this: chemicallythe basis of any living substance, without any exception, ishydrocarbon compounds. It is known that a living organism consists of a combinationa fairly limited number of chemical elements. So let's say 96% of the massThe human body is made up of common elements such as carbon (C)hydrogen (H), nitrogen (N) and oxygen (O)So, to begin with, let's remember: in addition to water, the other basis of all organicallycompounds on earth are carbohydrates. They are simplecompounds consisting, I repeat, of carbon (C), hydrogen (H) and oxygen (O)in different ways, and are usually expressed by the general formula CnH2nOn. For this momentI pay special attention. Comparing these two moments, we can already a priorithat is, before any experience, moreover, with one hundred percent certainty they will saythat water, as the basis of life, must also be a hydrocarboncompound. And in his book "Eternal mysteries of science (through the eyes of an amateur)", leaning on the data available in science, I consistently prove that water is indeedhas the formula not H2O, but CH2O, or, in other words, is a hydrocarboncompound, and thus organic matter. Only in this capacity, and notWhat other, it can serve as the basis of all life on Earth.

Now for the proteins. They are also exclusively complex organic compounds, consisting of all the same elements familiar to usnamely carbon, oxygen and hydrogen. In other words, you can completelyreason to assert that all living things consist of various combinations of the sameelements of which water itself consists, if, of course, based on its formulasCH2O. This fact puts everything in its place without any exaggeration and additional masses.artificial constructions and props, serving only to somehow bindincoherent. So, the point is small: to prove that water is really presentis an organic substance. Let's start with this.

No need to prove that water is not only the main, but also the only absolutely necessary substratum of all living things. However, the whole point, again, is thatfor water to play such a role, it must itself be organicallysubstance. This is where the whole snag lies, since modern science, and after notand all people who blindly believe in her conclusions continue to believe that water isinorganic substance, all with the same well-known to every schoolchild formula H2O It is this formula that the whole world science has been beating its forehead against for more than two hundred years.the time when the French chemist Lavoisier told the world that water consists of twoelements - hydrogen and oxygen, from which it naturally followed that she eatsinorganic substance. Since that time, not only all unscientific, but, whatamazing, and the whole scientific world unconditionally believed in it (and, moreover, believes innow), which, in particular, is evidenced by a huge number of contradictorythe most fantastic hypotheses and theories regarding the origin of life. Whatto overthrow this "blissful" faith, a breakthrough is required here, similar to that whichmade at one time Copernicus, putting forward his heliocentric system instead ofPtolemaic geocentric hypothesisIn fact, think for yourself: not only amazing, but also downrightthe discouraging fact is that the simplestthought, namely: if water makes up to 90% of the mass of all living organisms, if without water all living things wither and die, then does it not follow from this with complete obviousness that water is the basis of life, and not in some figurative, symbolic sense, but in the most direct sense. In other words, as the main premise, it is necessary to recognize that water itself is an organic substance and, as such, it is not just the main, but the only basis of all life on Earth. If there is no water, there is no (and cannot be!) any life.

So, I repeat once again: water by its nature is an organic substance and its formula is not H2O, but CH2O, and in this capacity it is in fact (and not figuratively) the basis of all life on Earth. I will say more: the chemical substance, which received the name nitrogen (N) in chemistry, is actually also an organic substance (more precisely, the same hydrocarbon group CH2, which will be shown below)*. These two conclusions provide grounds for a completely new look at the origin of life. Life arose not in some ancient times under some exceptional conditions, as the scientific world still believes. No, it arises continuously and literally before our eyes, because its basis, water, is preserved. I repeat once again: in all living systems, 98% of the mass falls on the following four elements: hydrogen, carbon, oxygen, nitrogen. Proteins, nucleic acids, in short, all living things, mainly consist of the same elements. This moment should be taken as a starting point. The protein formula in its general form looks like this: CnH2nOn, or in its simplest version - CH2O. And here I ask for your attention! As scientists assure us, proteins and nucleic acids make up to 98% of the substance of every living organism. But at the same time, the same scientists claim that water is up to 90% of the same living organism. It turns out that proteins and water together make up about 200% of the substance of living organisms. But this cannot be: it is impossible for the same organism to consist of one hundred percent of one substance and one hundred percent of another substance. There is only one way out of this difficult, if not delicate, situation, namely: to recognize that water itself is an organic substance and, in this capacity, it is also the basis of protein bodies. In this case, everything falls into place. Here a fundamentally important question arises: does there exist on Earth in a free state and in volumes corresponding to the total mass of living bodies, such a substance that itself consists of a combination of hydrogen, carbon, oxygen and nitrogen? By answering it, we will answer not only the question of the origin of life, but also the question of what is its basis, its permanent foundation, allowing it not only to exist, but also to constantly reproduce itself. So: this substance is water and its formula is not H2O, but CH2O. It naturally follows from this that it is water (and nothing else!) that is the substance that contains all the above components of life: hydrogen, oxygen, carbon and nitrogen (what nitrogen actually represents will be discussed below) . In this sense, water does not just belong to the group of carbohydrates - it forms its basis, its main mass, and in this capacity represents the only, moreover, virtually inexhaustible source of all life on Earth. This eliminates the blatant contradiction between the content of water and proteins in living organisms, which was mentioned above, because in the formula proposed here, water itself forms the natural basis of both proteins and nucleic acids.

However, the whole intrigue here is that Lavoisier's water formula, H2O, has stood in the way of such recognition as a powerful and still insurmountable obstacle. The belief in its truth that has been preserved to this day, in turn, gave rise to a lot of various, sometimes the most fantastic theories and hypotheses regarding the origin of life, with which the history of sciences is full.

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