Water pollution and its consequences. Wastewater, its treatment. Wastewater pollution

Main pollutants Wastewater in industry these are phenols, sulfates, nitrates and iron compounds. Untreated wastewater is a source of elements toxic to humans and animals (salts heavy metals, pathogenic bacteria and microorganisms).

Atmospheric precipitation and water discharged from territories industrial enterprises And settlements through the sewer system or by gravity are called waste. Industrial wastewater contains substances that affect the general sanitary condition of the reservoir, change the organoleptic characteristics of water and contain substances toxic to humans and animals. What is the difference between storm, industrial and domestic wastewater? And how is the filtrate of industrial wastewater subsequently used?

Types of industrial wastewater

Wastewater from industrial enterprises can be divided into several groups based on the content of chemical components, environmental reaction and source. Depending on the type and nature of the wastewater, a system for purifying products of processed liquid raw materials from industrial production is also selected.

Based on the reaction of the environment, wastewater is divided into:

Non-aggressive (pH 6.5-8);

Slightly alkaline (pH 8-9);

Slightly acidic (pH 6-6.5);

Highly alkaline (pH greater than 9);

Strongly acidic (pH less than 6).

In the composition of all wastewater, two main groups of pollutants can be distinguished - conservative (not biodegradable) and non-conservative (easily decomposed during the process of self-purification of the reservoir).

Main pollutants

Industrial wastewater may contain petroleum products, heavy metals, soil particles, ores, fungi, bacteria, yeast and organic matter. The most common compounds found in water bodies are phenols, zinc compounds, copper compounds, ammonium and nitrate nitrogen, aniline, potassium xanthate, methyl mercaptan, lignin, etc. Depending on the source of wastewater formation, the nature of wastewater pollution can be assumed with a high degree of probability (Table 1).

Table 1. Types of pollutants

Source of pollution	Types of pollutants
Non-ferrous and ferrous metallurgy factories	Minerals, non-ferrous metals, sulfates, sulfuric acid, inkstone.
Oil refineries	petroleum products, suspended substances, hydrogen sulfide, iron compounds.
Coke and chemical enterprises	suspended substances, rhodanide,
Pulp and paper industry	Dissolved organic matter,
Machine-building and automobile factories
Textile enterprises	Dyes,

After appropriate treatment, the effluent can be used as process water or recycled products. One of the most promising methods for recycling industrial wastewater enriched with nitrogen, potassium or phosphorus is the use of waste industrial products for irrigation of agricultural land and pastures.

Sources used:

1. Popov A. M., Rumyantsev I. S. Environmental protection structures.

2. Sokolova V.N. Protection of industrial wastewater and disposal of sludge.

Under pollution water resources understand any changes in physical, chemical and biological properties water in reservoirs in connection with the discharge of liquid, solid and gaseous substances into them that cause or may create inconvenience, making the water of these reservoirs dangerous for use, causing damage national economy, public health and safety.

Pollution of surface and groundwater can be divided into the following types:

• 1. Mechanical- Mechanical pollution is characterized by the ingress of various mechanical impurities into water - sand, sludge, silt, etc. Mechanical impurities can significantly worsen the organoleptic characteristics and quality of water, and also negatively affect the living conditions of fish and the state of ecosystems. Thermal pollution is associated with an increase in water temperature as a result of mixing with warmer surface or process waters, resulting in a change in gas and chemical composition water, the proliferation of anaerobic bacteria, an increase in the number of hydrobionts and the release of toxic gases - hydrogen sulfide and methane. At the same time, water “blooming” occurs, as well as the accelerated development of microflora and microfauna, which contributes to the development of other types of pollution.
• 2. Chemical- Chemical pollution is a change in natural chemical properties water due to an increase in the content of harmful impurities in it, both inorganic (mineral salts, acids, alkalis, clay particles) and organic (oil and oil products, organic residues, surfactants, pesticides).
• 3. Bacterial and biological- Wastewater contains big number microorganisms, including disease-causing (pathogenic) bacteria, which makes this water hazardous from a sanitary point of view. Bacteria of typhoid fever, dysentery and other pathogens are found in household wastewater gastrointestinal diseases, as well as helminth eggs (worms) entering wastewater with secretions of people and animals.
• 4. Radioactive- Radioactive substances entering surface and The groundwater, can be of natural or artificial origin. The presence of natural radioactive substances in water is due to its contact with minerals containing radioactive isotopes (U238, Ra226, Th232), as well as interaction with the atmosphere, from which C14, Be10, H3 enter the water. The degree of radioactive contamination of water in this case is usually small.
• 5. Thermal- type of physical (usually anthropogenic) pollution environment characterized by an increase in temperature above natural levels. The main sources of thermal pollution are emissions of heated exhaust gases and air into the atmosphere, and the discharge of heated wastewater into reservoirs.

The main sources of pollution and clogging of water bodies are insufficiently treated wastewater from industrial and municipal enterprises, large livestock complexes, production waste from the development of ore minerals; water from mines, mines, processing and rafting of timber; discharges from water and rail transport; waste primary processing flax, pesticides, etc.

Pollutants entering natural bodies of water lead to qualitative changes in water, which are mainly manifested in changes in the physical properties of water, in particular, the appearance unpleasant odors, appearance in it harmful substances, substances on the surface of the water and their deposition at the bottom of reservoirs.

Industrial wastewater is contaminated mainly with waste and emissions from production. Their quantitative and qualitative composition is varied and depends on the industry and its technological processes. They are divided into two main groups: those containing inorganic impurities, toxic, and those containing poisons.

The first group includes wastewater from soda, sulfate, nitrogen fertilizer plants, processing plants lead, zinc, nickel ores, etc., which contain acids, alkalis, heavy metal ions, etc. Wastewater from this group mainly changes physical properties water.

Wastewater of the second group is discharged by oil refineries, petrochemical plants, organic synthesis enterprises, coke plants, etc. The wastewater contains various petroleum products, ammonia, aldehydes, resins, phenols and other harmful substances. The harmful effect of wastewater from this group lies mainly in oxidative processes, as a result of which the oxygen content in water decreases, the biochemical need for it increases, and the organoleptic characteristics of water deteriorate.

Phenol is a rather harmful pollutant in industrial waters. It is found in wastewater from many petrochemical enterprises. At the same time, they sharply decrease biological processes reservoirs, the process of their self-purification, the water acquires a specific smell of carbolic acid.

IN last years waste water problem is becoming increasingly acute and relevant throughout the world, including in Russian Federation. In progress economic activity modern society consumes considerable amounts of water, most of which as a result becomes contaminated with a variety of substances. When they enter the environment, enormous damage is caused to the environment, and therefore they are subject to mandatory cleaning. To ensure it properly, it is necessary to use special equipment and technological complexes with the help of which the established wastewater pollution standards, defined in the relevant documents. The Flotenk company is one of those Russian organizations, which successfully works on wastewater treatment problems. For many years now, it has been developing and producing devices that allow for the effective separation of harmful substances contained in wastewater from industrial enterprises, Agriculture, housing and communal services and transport. This equipment allows you to bring degree of pollution wastewater to levels at which they can be discharged into the environment without causing damage to it.

Main wastewater contaminants and methods for their removal

Anthropogenic factors wastewater pollution is quite diverse and leads to the presence of mechanical, chemical and biological impurities in it, which must be removed by treatment facilities. As a rule, they are contained in wastewater in complex, in different concentrations, which significantly complicates the solution of the problem of wastewater treatment. Mechanical impurities are in most cases sand, various small solid particles of industrial or agricultural waste. Their separation from wastewater is usually carried out in special sand separators and settling tanks, where they settle naturally, under the influence of gravity. In addition, to separate mechanical impurities, Flotenk equipment uses meshes and filters. Sources of wastewater pollution, such as industrial and agricultural enterprises, “saturate” them with a considerable amount of various chemical compounds. Their separation is often a very complex problem and requires the use of expensive equipment and special reagents. To eliminate organic impurities, special microorganisms are actively and successfully used, which, as a result of their vital activity, decompose them into safe components. As for contaminants of biological origin (bacteria and other microorganisms), chlorine was previously actively used to neutralize them, and now more advanced technology for treatment with ultraviolet radiation is being increasingly used.

Wastewater pollution from industrial enterprises

The source of many environmental problems associated with wastewater disposal, are industrial enterprises. Technological processes Production in almost all industries involves the generation of wastewater contaminated with a wide variety of substances. To date industrial pollution wastewater is one of the most significant threats to the environment. Industrial enterprises, according to current legislation, must mandatory use treatment facilities to neutralize Negative influence wastewater, however, this requirement, unfortunately, is not always fully met. Pollution indicators Discharges from industrial facilities often significantly exceed established standards. In most cases, as practice shows, this is due to the fact that treatment facilities that are outdated, both morally and physically, are used, which are subject to reconstruction and modernization. This work is successfully carried out by the Flotenk company, using what it develops and produces in its own production facilities modern, high-performance and efficient equipment. Its specialists produce pollution calculation, determine many other important parameters, focusing on which they design, manufacture, install and put into operation all elements of wastewater treatment plant complexes.

Questionnaire for calculating and ordering treatment facilities for industrial enterprises:

Wastewater pollution from agricultural objects

Environmental problems of wastewater agricultural origin are also very serious. Enterprises of the agrarian-industrial complex often discharge into the environment wastewater that has such indicators of the presence of mechanical, chemical and biological impurities that many times exceed the maximum permissible standards. Decline wastewater pollution concentrations agricultural origin to the required level must be ensured by their high-quality cleaning using modern equipment. Only it can guarantee such quantitative and qualitative indicators of wastewater pollution of this type, which allow their removal without harm to the environment. The specificity of agricultural production is that its livestock and crop production units produce wastewater that has completely different composition of contaminants: in the former, impurities of organic and biological origin predominate, and in the latter, impurities of inorganic origin. Therefore, the approach to their cleaning, the methods and methods used for this, and the composition of the equipment must be different. When arranging treatment facilities at agricultural enterprises, specialists from the Flotenk company must take this circumstance into account, and therefore, at various facilities they install equipment that separates the corresponding types of pollution.

Domestic wastewater pollution

Human wastewater pollution is actively produced not only “thanks” to it economic activity, but household. Residential facilities and social and cultural facilities produce a significant amount of wastewater, which is discharged either to centralized or autonomous sewer systems, and are then subject to treatment and release into the environment. Mechanical, biological and organic wastewater pollution, formed as a result of human household activities, are removed by wastewater treatment plants very effectively. It should be noted that concentration of household wastewater contaminants is relatively low, and modern equipment does a good job of removing them. Those devices for the treatment of household wastewater, which are developed and produced by the Flotenk company, differ high efficiency, ease of operation and maintenance.

Questionnaire for calculating and ordering wastewater treatment facilities for enterprises:

Preventing environmental pollution from wastewater

Prevention of pollution of water bodies by wastewater, as well as protection surface waters from wastewater pollution - these are the most important tasks facing modern society. Their effective and comprehensive solution is possible only with the use of advanced wastewater treatment technologies and modern equipment.

Pollution with mineral compounds is usually presented in the form of sand, particles of clay, ore, slag, mineral salts, solutions of acids, alkalis and other substances. Organic pollution, according to its origin, is divided into plant and animal. Plant organic compounds are the remains of plants, fruits, vegetables, cereals, paper, etc. Pollution of animal origin can be physiological secretions of people and animals, the remains of dead animals, and adhesives. Biological pollution includes contamination by various microorganisms, such as fungi, small algae and bacteria. This pollution enters the reservoir mainly with domestic wastewater and with wastewater from industrial enterprises such as slaughterhouses, tanneries, primary wool processing factories, fur factories, and microbiological industry enterprises. In addition, floating substances may appear on the surface of the reservoir. Pollution entering a reservoir causes changes in the physical and organoleptic properties of water: transparency, color, smell and taste. The chemical composition of water also changes, as substances appear in it that change the active reaction of water and increase the content of organic and inorganic compounds. Pollution of organic origin requires a large amount of oxygen for its oxidation, which, in turn, reduces the content of oxygen dissolved in water. The number and types of microorganisms change, and sometimes pathogenic ones appear. Waste from city enterprises, fecal wastewater, precipitation and the various pollutants they wash away. Pollution of open reservoirs, underground and groundwater in this way has become especially large in capitalist countries, where many rivers have turned into sewers. They carry kitchen waste, laundry dirt and water, hospital waste, metals and acids, petroleum products from gas stations and airports, pesticides and mineral fertilizers from agricultural areas, etc. This leads to the death of representatives of river fauna and depletes oxygen reserves in the water. Pollution of water bodies worsens their sanitary condition, which, in turn, complicates the use of water bodies for domestic purposes and irrigation, causing great damage fisheries, forces the development of additional measures to protect water from pollution.

Biological pollution enters water bodies with domestic and industrial wastewater, mainly from enterprises in the food, medical and biological, and pulp and paper industries. This type of pollution is assessed by the biochemical consumption of oxygen, which is consumed in 5 days by microorganisms that are destructors for the complete mineralization of organic substances contained in 1 liter of water.

Chemical pollution enters water bodies from industrial, surface and waste waters.

wastewater. These include: petroleum products, heavy metals and their compounds, mineral fertilizers, detergents. The most dangerous of them are: lead, mercury, cadmium.

Physical pollution enters water bodies with industrial wastewater, during discharges from mine workings, quarries, during washouts from the territories of industrial zones, cities, transport highways, due to the deposition of atmospheric dust.

The level of water pollution for certain indicators exceeds the maximum permissible standards by tens of times. The highest level of water pollution is observed in the river basins: Dniester, Pechora, Ob, Yenisei, Amur, Northern Dvina, Volga and Ural, i.e. rivers located directly in industrial and agricultural zones.

Anthropogenic impact on the hydrosphere leads to a decrease in reserves drinking water; changes in the condition and development of flora and fauna of water bodies; disruption of the circulation of many substances in the biosphere; a decrease in the biomass of the planet and, as a result, the reproduction of oxygen.

It turns out that 75 g of dry weight in solid form per person per day ends up in the ocean

Thus, the consequences of drinking contaminated water for humans are various intestinal and infectious diseases - cholera, typhoid, hepatitis, dysentery, gastroenteritis. In addition, water pollution leads to deterioration of the skin, negatively affects the condition of the hair, and leads to damage to teeth. The kidneys and liver are the risk areas for which drinking contaminated water has the most detrimental consequences.

Negative consequences of water pollution, namely the high content of lead, cadmium, chromium, benzopyrene in it, for humans is expressed in a rapid deterioration in health. Critical accumulation of these harmful elements in the body often causes the appearance of cancer, as well as disorders of the central and peripheral nervous systems. Escherichia coli, enteroviruses are harmful microorganisms that have negative impact on the functioning of the gastrointestinal tract

Cleaning of drains

The concept of wastewater should be understood as water (effluent) that is contaminated with various types of waste and waste. Depending on the origin and composition, wastewater is usually classified into: domestic, industrial (production) and atmospheric. Domestic wastewater, the result of human activity, the main pollutants of which are household and physiological waste. Industrial or industrial wastewater is formed as a result of the activities of enterprises; their main pollutants are industrial waste (there are: contaminated and slightly contaminated, i.e. not requiring pre-treatment). Storm water, these are surface, storm drains, which include melt and rain water, as well as water from irrigation. Deep wastewater treatment, large ecological problem, requiring targeted and emergency measures. Events for wastewater treatment, help prevent environmental pollution from industrial and domestic wastewater, and the use and application latest technologies, is an urgent need to solve the problem of pollution.

Cleaning of drains– a complex process for treating wastewater in order to remove pollutants from it; at the end of the process, purified water and highly concentrated solid waste (completely ready for disposal) are formed. Since the wastewater treatment process is multi-stage, it has several treatment stages and treatment methods.

Among the main wastewater treatment methods, the following are distinguished:

mechanical wastewater treatment– the first stage of purification, which removes solid impurities and coarse substances;

chemical wastewater treatment– adding reagents to wastewater in order to neutralize and disinfect it;

physical and chemical wastewater treatment– removes small and finely dispersed particles, as well as dissolved inorganic substances and organic compounds;

biological wastewater treatment– purification of wastewater by aerobic and anaerobic microorganisms, the result is oxidation and reduction of the organic component of wastewater.

After using one or another wastewater treatment method, it is most advisable to disinfect wastewater. The most common disinfection method is chlorination of clarified wastewater. In addition to chlorination, there are other methods of wastewater disinfection, such as ozonation and treatment with electrolysis and bactericidal rays.

We must understand that everyone wastewater treatment method has its advantages and disadvantages, therefore, to obtain the best, effective and stable result, it is customary to use a combination or alternation of the above wastewater treatment methods. The combination of wastewater treatment methods represents a multi-stage waste treatment and disposal. In general, the choice of purification method is determined by the nature of the contaminants, the concentration of harmful impurities, as well as the requirements for purified water. A prerequisite for the treatment methods used is the minimum discharge of wastewater into the environment.