Water conservation in nature message. Industrial wastewater treatment
Personally, I can't imagine my life without water. Water is widely used in everyday life. Every day of my life starts with water procedures. To cook food, to make tea, to wash clothes or wash floors - all this requires water. It also applies to other industries. Without it, life on Earth is simply impossible. Do you realize the importance of this familiar liquid?
Water pollution: what causes it
The life activity of people is developing too actively. Rapid progress leads to numerous environmental problems, including those related to water. Solving these problems is extremely important for all mankind.
Water pollution occurs for many reasons, which are not even always related to human activity. So, the sources of pollution:
Protection of water from pollution
This is perhaps one of the most important tasks of mankind. First of all, the protection of water from pollution is aimed at minimizing discharges into rivers and other water bodies. The industry is developing new, more advanced technologies for wastewater treatment. My opinion is this: in general, it is necessary to significantly increase fines for discharges, and the proceeds from this should be distributed to the design and assembly of new technologies.
In addition, it is also important proper upbringing new generation of people. From childhood, it is necessary to instill respect for nature, to teach respect for water, not to pour it unnecessarily, and also not to drain harmful substances into the sewer.
The protection of water resources from depletion and pollution by harmful substances provides for a set of measures: 1) development of relevant legislative acts; 2) organization of monitoring of water bodies; 3) protection of surface and ground waters, including treatment of industrial and domestic wastewater; 4) preparation of water used for drinking and household purposes; 5) state control over the use and protection of water resources.
Federal legislation and protection of water bodies
Water legislation includes the Water Code of the Russian Federation and federal laws and other regulatory legal acts adopted in accordance with it, as well as laws and other regulatory legal acts of the constituent entities of the Russian Federation (republics, territories, regions).
The purpose of water legislation is to regulate relations in the field of use and protection of water bodies. At the same time, the use of water bodies for drinking and household water supply is a priority. For this type of water supply, it is necessary to use surface and underground water bodies protected from clogging and pollution.
All water users are obliged by law to reduce withdrawals and losses of water, to prevent clogging, depletion and pollution of water bodies. It is prohibited to discharge sewage (WW) into water bodies if the latter are classified as specially protected, contain natural healing resources, are located in places of mass recreation of the population or resort areas, as well as in places of spawning and wintering of valuable fish species, etc.
The main role in water protection is played by the state accounting of surface and ground waters, which is carried out for the purposes of current and advanced planning rational use of water resources, their restoration and protection. It is based on state monitoring data and accounting data provided by water users. Codes of systematized data on water bodies, water resources, regime, quality and use of water, as well as on water users are included in the water cadastre.
The Water Code of the Russian Federation prohibits putting into operation:
- any objects that are not equipped with treatment facilities and devices that prevent clogging, depletion and pollution of water bodies;
- waste and catchment facilities, as well as hydraulic structures (HTS) without fish protection devices;
- objects of industry, agriculture and other complexes that do not have sanitary protection zones;
- irrigation, watering and drainage systems, reservoirs, dams and canals until the completion of measures that prevent their harmful effects on water bodies.
An important role in the protection of water resources is played by the licensing of water use, as well as the discharge of waste and other waters. The procedure for licensing water use is regulated by Art. 48-53 and 83 of the Water Code of the Russian Federation, as well as the Decree of the Government of the Russian Federation "On approval of the Rules for the provision of state-owned water bodies for use, the establishment and revision of water use limits, the issuance of a license for water use and a distribution license."
Violation of the requirements for the protection and rational use of water bodies entails the restriction, suspension and even prohibition of the operation of economic and other objects that have a negative impact on the state of water bodies. The decision on this is made by the Government of the Russian Federation or the executive authorities of its subjects. Preliminarily, a presentation is given by a specially authorized state body for managing the use and protection of the water fund, specially authorized state bodies in the field of protection of environmental protection systems, and a state body for sanitary and epidemiological supervision.
Monitoring of water bodies
State monitoring of water bodies, being an integral part of the system of state monitoring of the environment, includes monitoring surface water land and sea objects, monitoring of underground water bodies, monitoring of water management systems and structures.
It provides for: 1) constant monitoring of their condition, qualitative and quantitative indicators of both surface and groundwater; 2) collection, storage and processing of observational data; 3) creation and maintenance of data banks; 4) assessment, forecasting of changes in the state of water bodies and the transfer of relevant information to government bodies of the Federation and its subjects.
State monitoring of water bodies is carried out by the Ministry of Natural Resources (MNR), the Federal Service for Hydrometeorology and Monitoring environment(Roshydromet) and other specially authorized state bodies in the field of environmental protection.
The Ministry of Natural Resources of the Russian Federation is responsible for the development of a network of stations and observation posts at water bodies, the development of automated information systems (AIS) for conducting state monitoring of water bodies, and the creation of an observation network of posts at water management systems and facilities. Roshydromet monitors the pollution of land surface waters, covering 154 reservoirs and 1172 watercourses, where hydrochemical parameters are studied.
The Sanitary and Epidemiological Service of Russia is responsible for the sanitary protection of water bodies. It has 2,600 sanitary and epidemiological institutions, 35 research institutions of a hygienic and epidemiological profile. In addition, there is a network of sanitary laboratories at enterprises engaged in studying the composition of wastewater and the quality of water in reservoirs.
Currently, much attention is paid to the deployment of a network of automated stations that are able to measure and control changes in dozens of water quality indicators, and very quickly.
Schemes for the integrated use and protection of waters
In order to develop comprehensive measures aimed at meeting the prospective water needs of the population and the national economy in combination with water protection, general, basin and territorial schemes are drawn up.
General schemes for the integrated use and protection of waters determine the principal directions for the development of the country's water management, which makes it possible to quite clearly identify the technical and economic feasibility and sequence of the largest water management measures. Basin schemes for river basins and other water bodies are developed on their basis. Territorial schemes developed on the basis of the general and basin schemes cover specific economic regions of the country and subjects of the Russian Federation.
To coordinate the activities of various water users aimed at the restoration and protection of water bodies within the basin, the Water Code of the Russian Federation requires the drawing up of a so-called basin agreement on the restoration and protection of water bodies. These agreements are concluded between the specially authorized state body for managing the use and protection of the water fund and the executive authorities of the constituent entities of the Federation, which are located within the basin of a water body (for example, Lake Baikal).
The basin agreement is based on water management balances, schemes for the integrated use and protection of water resources, state programs for the use, restoration and protection of water resources, and without fail takes into account the proposals of state authorities of the constituent entities of the Russian Federation (territories, regions, etc.).
In 1996, the Government of Russia adopted a resolution “On the Procedure for the Development and Approval of Standards for Maximum Permissible Harmful Impacts on Water Bodies”, according to which MPE standards for water bodies should be developed and approved for the basin of a water body or its section in order to maintain surface and groundwater in proper condition.
Surface water protection
Surface waters are waters permanently or temporarily located on the earth's surface. These are the waters of rivers, temporary streams, lakes, reservoirs, ponds, reservoirs, swamps, glaciers and snow cover.
Measures for their protection are provided for in the Rules for the Protection of Surface Waters, approved by the USSR State Committee for Nature Protection dated February 21, 1991. Particular attention is paid to the protection of water bodies when wastewater is discharged into them.
Surface waters are protected from clogging, depletion and pollution. To prevent clogging, measures are taken to prevent the ingress of garbage, solid waste and other objects that adversely affect water quality and habitat conditions for aquatic organisms. Strict control over the minimum allowable runoff of water, limiting their irrational consumption contribute to the protection of surface waters from depletion.
Very important and difficult problem is to protect surface water from pollution. To this end, a number of measures are envisaged, in particular: monitoring of water bodies; created-
Nie water protection zones; development of non-waste and waterless technologies, as well as systems of circulating (closed) water supply; wastewater treatment (industrial, domestic and others); purification and disinfection of surface and ground waters used for drinking water supply and other purposes.
Organization of water protection zones
To maintain water bodies in a state that meets environmental requirements, excludes pollution, clogging and depletion of surface waters and preserves the habitat of animals and plants, water protection zones are organized. They are territories adjacent to the water area of rivers, reservoirs and other surface water bodies; they establish a special regime for the use and protection of natural resources, as well as the implementation of other activities. Within these zones, coastal protective strips are established, where it is not allowed to plow the land, cut down forests, place farms, etc.
According to the Water Code of the Russian Federation, the government of the country is entrusted with the duty to establish the size and boundaries of water protection zones and their coastal protective strips. Thus, the minimum width of these zones for lakes from the average long-term water line in the summer period and for reservoirs from the water line at a normal backwater level with a water area up to 2 km 2 is 300 m, more than 2 km 2 - 500 m.
A similar indicator for rivers is determined by the length of the river: from the source to 10 km - 15 m; from 11 to 50 km - 100 m; from 51 to 100 km - 200 m; from 201 to 300 km - 400 m; over 500 km - 500 m.
Of great importance in the protection of surface waters from clogging and pollution are water-protective forest plantations around natural and artificial reservoirs and watercourses. They are designed to protect them from the destructive effects of winds and water entering them from the catchment area, as well as to reduce water loss to evaporation. Forest plantations improve the water regime of reservoirs, the sanitary and hygienic conditions of the coast and its landscape and decorative design, the quality of water in reservoirs, reduce their siltation, and reduce the loss of land due to the processing of banks by waves (abrasion). Water protection forest plantations located around drinking reservoirs must meet the sanitary and hygienic requirements that apply to drinking reservoirs. They include up to 50% of conifers, which are placed in the extreme 2-3 rows from the side of the reservoir to protect its mirror from falling leaves.
In addition to water protection zones, in order to ensure protection, sanitary protection districts can also be established. They are established in order to protect water bodies used for drinking and domestic water supply, as well as containing natural healing resources.
Domestic wastewater treatment
During wastewater treatment (SW), the destruction or extraction of harmful substances from them is carried out.
A complex of engineering structures and sanitary measures that ensure the collection and removal of polluted wastewater from populated areas and enterprises, their purification, neutralization and disinfection (destruction of dangerous microorganisms) is sewage.
According to Yu.V. Novikov (1998), power treatment facilities sewerage in the country exceeds 58 million m 3 per day, and the length of sewer networks in settlements has reached 114 thousand km. Through sewerage systems, cities and other settlements discharge 21.9 billion m 3 of wastewater per year; of which only 76% passes through treatment facilities. Surface water bodies (and these are the main sources of drinking water supply) annually receive 13.3 bln m According to official data, 60% of operated sewage treatment plants are overloaded, about 38% have been in operation for 25-30 years and require urgent reconstruction. Add to this that 52 cities and 845 urban-type settlements do not have centralized sewerage systems at all.
In order to provide economic incentives for environmental protection measures, the Government of the Russian Federation in 1996 adopted a resolution "On the collection of fees for the discharge of wastewater and pollutants into the sewerage systems of settlements", according to which the procedure and amounts of payments for the discharge of wastewater and pollutants into the sewerage systems of settlements are determined. from enterprises and organizations diverting their CBs to these systems. At the same time, the fee is distributed in the ratio: to the federal budget - 40%, to the budget of the constituent entities of the Federation - 60%. The funds received should be directed to the restoration and protection of water bodies.
Cleaning of domestic wastewater can be carried out by mechanical and biological methods. During mechanical cleaning, WW is divided into liquid and solid parts. The liquid is further subjected to biological purification, which can be natural and artificial. Natural biological treatment of wastewater is carried out on agricultural fields of irrigation and filtration, as well as in biological ponds. Artificial biological treatment is carried out on special facilities (biofilters, aeration tanks). The resulting sludge is processed on sludge sites or in special devices - metatanks.
Industrial wastewater is pre-passed through local treatment facilities, where it is freed from suspended particles or specific toxic components using mechanical, chemical or physico-chemical cleaning methods.
In practice, several types of irrigation systems are used: continuous flooding, flooding along furrows and strips, sprinkling, subsoil irrigation. The latter method most satisfies the sanitary-technical, epidemiological, agro-economic, water management and, importantly, aesthetic requirements. When using treatment facilities with irrigation fields and with year-round intake of WW with seasonal regulation of their supply, watering is carried out only during the growing season, and the rest of the time, WW enters the storage ponds.
Biological ponds are designed for deep cleaning of domestic and industrial wastewater, previously treated for VOCs. There are ponds with natural and artificial aeration (with the help of mechanical aerators), their depth is usually within 1-3 m. Aquatic vegetation plays an important role in oxidative processes, which helps to reduce the concentration of nutrients and regulates the oxygen regime of the reservoir.
Constructions of artificial biological treatment. Biological treatment is based, as is known, on the process of biological oxidation of organic compounds contained in WW. Biological oxidation is carried out by a community of microorganisms (biocenosis), which includes many different bacteria, protozoa and a number of more highly organized organisms - algae, fungi and aphids, interconnected in a single complex by complex relationships (metabolism, symbiosis and antagonism).
Biofilters are widely used at daily consumption of household and industrial wastewater up to 20-30 thousand m 3 /day.
The biofilter is a tank that is filled with feed material (gravel, expanded clay, slag). Waste water is poured above the surface of the feed material; evenly over it is distributed through the feed material, on the surface of which a biological film (biocenosis) is formed, similar to activated sludge in an aerotank.
When operating biological treatment facilities, one should carefully observe the technological regulations for their work, avoid overloading and especially bursts of toxic components, significant deviations from the active reaction of the environment, since these violations can have a detrimental effect on the vital activity of microorganisms and disable biological oxidizers.
Disinfection of wastewater that has passed the stage of biological treatment, as well as those that have not passed it, is carried out with gaseous chlorine, bleach, and also sodium hypochlorite. In recent years, methods of disinfecting wastewater with the help of ozone and UV rays, as well as an electric pulse discharge, have been intensively introduced.
Waste water outlet locality should be located below its boundary along the watercourse. Discharge of sewage, waste and drainage waters within the boundaries of the settlement is allowed in exceptional cases on the basis of permits issued by the bodies for the protection of the environmental protection system and agreed with the bodies of state sanitary supervision.
Groundwater protection
The surface hydrosphere is inextricably linked with the atmosphere, underground hydrosphere, lithosphere, and other components of the OPS. Therefore, given the interconnection of all its ecosystems, it is impossible to ensure the purity of surface water bodies and watercourses without adequate protection of groundwater. The latter is to prevent the depletion of groundwater resources and protect them from pollution.
According to Art. 1 of the Water Code of the Russian Federation, groundwater is water, including mineral water, located in groundwater bodies. At the same time, groundwater and the rocks containing it are recognized as a single water body.
In order to combat the depletion of fresh groundwater reserves, which are a strategic reserve for drinking water supply for future generations, the following measures are envisaged: 1) rational distribution of water intakes over the area; 2) regulation of the groundwater withdrawal regime; 3) clarification of the value of operational reserves (to prevent their depletion); 4) for self-flowing artesian wells, the establishment of a crane operating mode.
Sometimes, to prevent the depletion of groundwater, artificial replenishment is used by transferring part of the surface runoff into groundwater.
The fight against groundwater pollution includes preventive and special measures. Preventive measures are essential because they require the least cost. Special measures are aimed primarily at isolating sources of pollution from the rest of the aquifer (impervious walls, curtains), intercepting contaminated groundwater through drainage or pumping them out of special wells.
The most important preventive measure to prevent pollution of groundwater in areas of water intakes is the arrangement of sanitary protection zones around them.
Sanitary protection zones (SPZ) consist of three belts. The first belt includes an area at a distance of 30-50 m directly from the water intake (well). This is a strict regime zone, the presence of unauthorized persons and the performance of work not related to the operation of the water intake are prohibited in it. The second ZSZ belt serves to protect the aquifer from bacterial pollution, and the third - from chemical pollution. It is forbidden to place any objects that can cause this or that pollution, for example, livestock complexes. Logging, use of pesticides, etc. is not allowed.
The Ministry of Natural Resources of Russia in 1998 approved Guidelines on the development of standards for maximum permissible harmful effects (MAI) on groundwater bodies and maximum permissible discharges of harmful substances into groundwater bodies. MPE standards are a set of quantitative and qualitative indicators (characteristics) of processes and structures that can have a harmful effect on groundwater. If these standards are observed, the harmful effect does not exceed the permissible limits.
MPE standards are determined for each projected, under construction or operating object of economic activity in relation to a specific groundwater body, which may be affected by the specified activity.
Protection of small rivers
There are over 2.5 million small (up to 100 km long) rivers in Russia. They form almost half of the total volume of river runoff, up to 44% of the total urban population and almost 90% of the rural population live in their basins (Yu.V. Novikov, 1998).
Small rivers, being a kind of component of the geographic environment, act as a regulator of the water regime of certain landscapes, since they largely maintain balance and redistribute moisture. Let us add to this that they determine the hydrological and hydrochemical specificity of medium and large rivers.
Since the flow of small rivers is formed in close connection with the landscape of the basin, they are characterized by a high level of vulnerability, not only in case of excessive use of water resources, but also in the development of the watershed. Intensive economic activity causes especially great harm to small rivers. Because of this, they quickly overgrow and swamp, degrade and, in the end, disappear.
The protection of the waters of small rivers is closely connected with the protection from pollution of the territory from which the river collects its waters. Experts have calculated that more than 4,000 tons of organic matter, 6,000 tons of suspended solids, tens of tons of oil products enter the small rivers of the Vladimir Region every year, and more than 2,000 tons of ammonium nitrogen and 600 tons of nitrates are washed away from the fields by floods and rains.
Since the ability of small rivers to self-purify is significantly lower than that of large ones, it is important to create water protection zones on their banks and strictly maintain their regime. This zone (from 100 to 500 m wide) includes the floodplain, terraces above the floodplain, crests and steep bank slopes, ravines and gullies. It is recommended to arrange a device along the banks, strips of forest or meadows with a width of 15 to 100 m. Plowing slopes along the coast, grazing livestock, building livestock farms, and treating fields adjacent to rivers with pesticides is prohibited. The ravines adjacent to the water protection zone must be strengthened, the springs that feed the small river must be cleared.
Artificial aeration contributes to the increase in the ability of small rivers to process biochemically oxidized impurities that come with runoff and discharges of polluted waters. This is achieved by installing a dam with overflow, thanks to which the water falling even from a small height is well saturated with oxygen.
Industrial wastewater treatment
Methods for the treatment of industrial wastewater are divided into mechanical, chemical, physico-chemical and biological.
For mechanical cleaning, the following structures are used: gratings, on which coarse impurities larger than 5 mm in size are retained; sieves that retain impurities of CB up to 5 mm in size; sand traps used to trap mineral contaminants of the NE, mainly sand; grease traps, oil traps, oil traps, tar traps for trapping corresponding contaminants from waste water, which are lighter than water; settling tanks for settling suspended solids with a specific gravity greater than one.
The principle of operation of the sand trap is based on the fact that, under the influence of gravity, particles whose specific gravity is greater than the specific gravity of water, as they move along with water in the tank, settle to the bottom. In accordance with the laws of the hydraulics of the flow, grains of sand are carried away with water only at a certain flow rate. When this speed decreases, sand grains settle to the bottom of the tank, and the water flows further.
Sand traps are horizontal, in which water moves in a horizontal direction, vertical, in which water moves vertically upwards, and round, with a helical (translational-rotational) movement of water.
In the last sand traps, processes similar to those observed in a tea cup take place. When the tea poured into the cup is stirred, the tea leaves gather in the center of the cup. During the circular motion of SW in a round sand trap, large sand particles are similarly collected in its center. Through a hole in the center of the sand trap, they enter a special chamber.
During mechanical cleaning, up to 90% of insoluble mechanical impurities of various nature (sand, clay particles, scale, etc.) are removed from industrial wastewater by straining, settling and filtering, and up to 60% from household wastewater.
In order to clean wastewater from oil products, the settling method is also widely used, which in this case is based on the ability to spontaneously separate water and oil products. The particles of the latter under the action of surface tension forces acquire a spherical shape, and their sizes are in the range from 2 to 3 10 2 microns. The settling process is based on the principle of separation of oil products under the influence of the difference in the densities of water and oil particles. The content of oil products in wastewater is within a wide range and averages 100 mg/l.
The separation of oil products is carried out in oil traps. Dirty water is supplied to the receiving chamber and, passing under the partition, enters the settling chamber, where the process of separation of water and oil products takes place. Purified water is removed from the oil trap, and oil products form a film on the surface of the water and are removed by a special device. Grease traps, oil traps and resin traps are similarly arranged, using the principle of the difference in density of water and contaminants that are lighter (for example, oil) than water.
Chemical methods are used to clean industrial wastewater. The main techniques are neutralization and oxidation-reduction, they can be used both as independent and as auxiliary in combination with others.
Industrial technological processes take place both in acidic (excess H + ions) and alkaline (excess OH -) environments, which leads to the appearance of appropriate effluents. To balance the number of H + and OH ions - - this is the essence of the neutralization method in wastewater treatment.
Rational is the mutual association of acidic and alkaline effluents. Disposal of acidic and alkaline wastewater through a single pipeline system is not always advisable, as this can cause precipitation in the pipes and, as a result, clog the network.
In order to neutralize acidic waters, alkaline reagents are used: lime CaO, slaked lime Ca (OH) 2, soda ash Na 2 CO 3, caustic soda NaOH, ammonia water, as well as filtration through neutralizing materials (limestone, dolomite, magnesite, chalk).
To neutralize alkaline waters, acids are most often used: sulfuric, hydrochloric, nitric, less often acetic. It is possible to use for these purposes also flue gases containing CO 2 SO 2 , NO 2 .
Wastewater containing oxidized variable-valent elements (Cr +6, Cl -, Cl +5, N -3, N +5, etc.) is neutralized in two stages. At the first stage, elements that are in the highest (or high) oxidation state are reduced to a lower (or intermediate) valence, at which this element can be separated from the liquid phase in the form of a precipitate, gas or transferred to a low-toxic form at the second stage of purification.
The oxidizing method is used in the purification of industrial wastewater from toxic cyanides, sulfides, mercaptans, phenols, cresols, etc. The reagents are chlorine and its derivatives (hypochlorites, dioxide, chlorates), oxygen, ozone, permanganates, chromates and dichromates, hydrogen peroxide. The recovery method is used to purify wastewater from nitrites and nitrates, chromates and dichromates, chlorates and perchlorates, sulfates, bromates, iodates. The reducing agents in this case are oxidized variable-valent elements contained in sulfites, sulfides, ferrous salts, sulfur dioxide (from flue gases).
Physico-chemical methods are also mainly used for the purification of industrial wastewater. However, recently some of them have been used in the purification of urban wastewater. These include, in particular, coagulation - the process of enlargement of colloidal particles in a liquid due to the electrostatic forces of intermolecular interaction. With an initial particle size of 0.001 - 0.1 µm after coagulation, their size reaches 10 µm or more, i.e. those sizes at which they can be isolated by mechanical methods. Coagulation not only leads to particles sticking together, but also violates the aggregative stability of the polydisperse system, resulting in the separation of solid and liquid phases.
A kind of coagulation is the process of flocculation - coarsening of fine particles due to electrostatic interaction under the influence of specially introduced polyelectrolytes - flocculants. In the practice of water treatment, activated silicic acid and polyacrylamide (PAA) are most widely used. The dose of coagulants and flocculants depends on the composition of the treated water and is specified during commissioning at the treatment plant.
Flotation is the process of separating suspended and emulsified contaminants from water into a foam layer as a result of adhering to gas bubbles supplied from below in the liquid to be purified.
Sorption is a method of deep purification of industrial wastewater from dissolved organic and some inorganic contaminants. In water treatment processes, it can be used both independently and in combination with other biological and chemical methods. Sorption makes it possible not only to isolate and concentrate contaminants from wastewater, but also to utilize them in the technological process, and to use purified water in circulating water supply.
The mechanism of adsorption consists in the transition of a solute molecule from the volume of liquid to the surface of a solid sorbent under the action of its force field. Various natural and artificial materials are used as sorbents: ash, coke breeze, peat, zeolites, active clays, etc. Activated carbons are especially widely used for these purposes, the specific adsorption surface reaches 400-900 m 2 /g.
For concentrated WW containing organic contaminants of technical value, extraction is an effective purification method. It is based on the mixing of two mutually insoluble liquids (one of which is waste water) and the distribution in them, according to the solubility, of the polluted substance.
Various extractants are used organic matter: acetone, chloroform, butyl acetate, toluene, etc. The separation of the extractant and the extracted substance is carried out by distillation of the mixture. This determines one of the main requirements for choosing an extractant: different boiling points of the extractant and the substance to be separated. After separation of the mixture, the extractant is reused in the water treatment cycle, and the substance is disposed of.
Ion exchange is the extraction of cations and anions from contaminants dissolved in SW using ion exchangers, which are solid natural or artificial materials (for example, artificial ion exchange resins). Substances extracted by ion exchange are subsequently disposed of or destroyed. Cation exchangers exchange with cations, anion exchangers with anions.
Despite the efficiency and environmental friendliness, the ion-exchange method has not found wide application in industry due to the shortage of ion-exchange resins and the need to organize a reagent economy for the regeneration of ion exchangers.
The biological method described above is the most environmentally friendly of all methods. One of the basic principles of ecology - "nature knows best" - is implemented here by microbial communities by turning complex environmentally hazardous substances into simple, harmless ones.
Mastering waterless and drainless technologies
It is estimated that 1 m 3 of untreated WW entering a natural water body can pollute hundreds of cubic meters of clean water, thereby creating unacceptable conditions for the life of hydrobionts. Therefore, technologies that either do not use water at all or do not form polluted effluents are promising. Their successful implementation into practice would completely solve the problem of protecting water bodies from pollution. Currently, in a number of chemical industries, for example, in the production of ammonia, synthetic methanol and other products, they switched from water cooling of high-temperature gas mixtures to air. Thus, the very acute issues of fresh water intake for industrial needs and the formation of polluted wastewater were removed.
Water supply technologies are also promising, which are characterized by minimal consumption of fresh water. With a closed technology, an enterprise takes water from a natural source, uses it to manufacture products, after which the resulting WW undergoes deep purification and returns to the cycle again. Any small losses of water, for example due to evaporation, are replenished by fresh water intake.
In a number of industries, closed water circulation schemes with local treatment have been partially implemented. Thus, in the petrochemical industry, circulating water supply saved 90% of industrial water.
Preparation of water for drinking purposes
The most important among water protection problems is the development of effective methods for preparing surface water for drinking purposes from an environmental and hygienic standpoint.
Pollution of natural sources of drinking water supply with insufficient efficiency of water treatment facilities entails a deterioration in the quality of drinking water supplied to consumers and creates a danger to public health in many regions of Russia, causes high level the incidence of intestinal infections, hepatitis, increases the risk of exposure to the human body of carcinogenic and mutagenic factors.
Every second inhabitant of our country is forced to use water for drinking purposes that does not meet hygienic requirements for a number of indicators; almost a third of the country's population uses decentralized water supply sources without adequate water treatment; the population of a number of regions suffers from a lack of drinking water and the lack of sanitary and living conditions associated with this. Russia's lagging behind developed countries in terms of average life expectancy and increased mortality (especially in children) are largely associated with the consumption of poor-quality water.
For more than 100 years, the method of water disinfection with chlorine has been the most common way to combat pollution in Russia. In recent years, it has been established that water chlorination poses a serious threat to human health, since extremely harmful organochlorine compounds and dioxins are formed along the way. It is possible to achieve a decrease in the concentration of these substances in drinking water by replacing chlorination with ozonation or treatment with UV rays. These progressive methods are being widely introduced at water treatment plants in many countries. Western Europe and USA. In our country, unfortunately, due to economic difficulties, the use of environmentally efficient technologies is extremely slow.
At a number of domestic water treatment plants, at the final stage, sorption processes using activated carbons (adsorbents) are used, which effectively remove oil products, surfactants, pesticides, organochlorine and other compounds, including those with carcinogenic properties, from water.
With a steady increase in technogenic pollution of surface waters in the world practice of drinking water supply in recent decades there has been a trend towards the transition to the use of artesian (underground) water. Artesian waters compare favorably with surface waters: the level of their mineralization, organic, bacterial and biological pollution is much lower. In some cases, such waters fully meet hygienic requirements and can be supplied to consumers, bypassing traditional preparation.
However, if artesian waters are oxygen-free by their hydrochemical nature (do not contain dissolved oxygen), then they may contain reducing ingredients (Mn 2+ ions, Fe 2+ and hydrogen sulfide) in concentrations exceeding the permissible ones. Then purification is necessary, which boils down to the treatment of water with strong oxidizing agents, for example, potassium permanganate, ozone, oxygen compounds of chlorine. As a result of processing, these impurities become insoluble and are then easily removed by filtration.
State control over the use and protection of water resources
In 1997, the Russian government approved the "Regulations on the implementation of state control over the use and protection of water bodies", according to which the specified control is carried out by the Ministry of Natural Resources (MNR), departments of state control over the use and protection of water bodies of territorial bodies (basin bodies, which operate on the territory of the subject of the Russian Federation).
The main task of the Ministry of Natural Resources is to exercise state control over compliance with the requirements of the Russian water legislation, standards, regulations, rules and other legal acts that are binding on all users of water bodies when they carry out all types of work related to the use and protection of water bodies, including internal sea waters and the territorial sea of the Russian Federation. Together with the bodies of the State Sanitary and Epidemiological Supervision, the Ministry exercises state control over the study, use and protection of underground water bodies, and together with the federal mining industrial supervision bodies - water bodies containing natural healing resources.
State inspectors for the control of the use and protection of water bodies are vested with broad powers, in particular, they have the right to: visit without prior notice objects and organizations that are water users and water consumers, as well as, if necessary, military, defense and other objects, taking into account the established regime for visiting them; give mandatory instructions for the elimination of violations of the regime for the use of water bodies identified during inspections and monitor their implementation; inspect and, if necessary, detain ships (including foreign ones) that have allowed illegal discharge of pollutants or have not taken the necessary measures to prevent pollution of water bodies; make demands to organizations (including sensitive ones) and individuals to take measures to improve the condition, use and protection of water bodies and to organize control over wastewater and their impact on water bodies; consider cases of administrative offenses and impose administrative penalties on persons guilty of violating water legislation.
It should be borne in mind that the decisions of the bodies of state control over the use and protection of water bodies are binding on all water users; they can only be appealed to a civil or arbitration court.
Questions for self-control
- Describe the role played by legislation in the integrated use and protection of water resources?
- What is water monitoring and who does it?
- Why are schemes for the integrated use and protection of water drawn up? Their types. What is a basin agreement?
- List measures for the protection of surface waters.
- Why are water protection zones established? What role do water conservation forests play?
- What structures are included in the system of artificial biological treatment?
- List activities. carried out to combat the depletion and pollution of groundwater.
- Why is the problem of protecting small rivers so acute at present?
- List the methods of wastewater treatment of enterprises.
- What are the main devices used in mechanical wastewater treatment?
- What processes are used in chemical and physico-chemical wastewater treatment?
- Describe the role of wasteless production in solving the problem of water protection.
- Why is drinking water chlorination dangerous for consumers? What alternative methods of water disinfection do you know about chlorination?
- Who exercises state control over the use and protection of water bodies? What are the powers of state inspectors?
Resources fresh water
Snow accumulates in the mountains at the same temperatures. The fallen snow gradually compacts and turns into firn (granular ice) and then into glacier ice. Ice has the ability to move (flow) under the influence of gravity at a speed of several meters to 200 m per year.
Cover glaciers are of considerable thickness, hide relief irregularities and occupy a large area (for example, the cover glacier of Antarctica with a thickness of about 2 km, and the glacier of Greenland). Huge blocks of ice are constantly breaking off from the edge of these ice sheets - icebergs, sitting aground or floating freely.
Mountain glaciers occupy the tops of mountains, various depressions on their slopes (kars, cirques) and valleys. Mountain glaciers are much smaller than cover glaciers and are more diverse.
Glaciers contain a large amount of fresh water. Partially, it is spent on feeding rivers (the water content of mountain rivers depends on the intensity of glacier melting). For arid regions of the world, glacial feeding of rivers is of great economic importance. Interesting projects are now being developed to use icebergs to supply fresh water to arid regions of Australia, Africa, South America and the Arabian Peninsula.
6. Swamps
Swamps - excessively moist areas of land with moisture-loving vegetation, the death and decomposition of which form peat. Depending on the sources of food, the swamps are divided into upland and lowland.
Raised bogs feed on atmospheric precipitation, are poor in mineral salts and are usually located on watersheds. The vegetation of these swamps is poor in species composition; sphagnum mosses predominate.
Lowland swamps occur in places where groundwater comes to the surface or is close to groundwater. A much richer mineral nutrition creates conditions for the growth of various vegetation here - green mosses, sedges, grasses, and tree species - alder and birch. As a result of peat accumulation, the surface of lowland bogs gradually rises. At a certain stage, the surface of the swamp can reach such a height at which the swamp vegetation can no longer use groundwater and switches to atmospheric precipitation: the lowland swamp is replaced by a raised one.
Bogs play an important role in nature: they humidify the air of the surrounding areas, they are habitats for many animal species and valuable plant species.
The swamps are used by man. Peat is developed on them, which is used as a fertilizer, fuel and chemical raw materials, berries, medicinal plants are harvested, part of the lowland swamps are drained and turned into agricultural land with high potential fertility. However, it should be remembered that not all swamps are subject to drainage, some of them must be preserved so as not to disturb the relationships that have developed in nature.
7. Protection of fresh waters.
7.1. Water as the most valuable natural resource. This is one of the most life-supporting natural environments that have developed in the process of evolution. In addition to other economic importance, the main role of fresh water reserves is to supply people with water, primarily for drinking. Clean fresh water is the limiting factor of human existence as a biological species.
Water, an integral part of the biosphere, has a number of anomalous properties that affect the physicochemical and biological processes occurring in ecosystems. These properties include very high and maximum heat capacity among liquids, heat of fusion and heat of evaporation; surface tension, dissolving power and dielectric resistance, transparency.
Water also has a characteristic increased migration capacity, which is important for its interaction with adjacent natural environments. Due to these properties, potential water can accumulate a lot of pollutants - chemical elements and pathogenic microorganisms.
Most of the water consumed on the globe is used in agriculture (70%), followed by industry and household needs. In many parts of the world, ¾ of the world's population is experiencing an acute shortage of clean fresh water. Therefore, the protection of fresh waters consists in their careful use: 1) economical water consumption with the use of more advanced technologies in industry and agriculture; 2) introduction of recycling water supply at enterprises; 3) prevention of water pollution, strict observance of wastewater treatment rules.
The task of water conservation is complex and costly. The cost of water protection ranks first among all the costs of nature protection. Therefore, unfortunately, so far it has been possible to solve only partially.
7.2. Reduction and anthropogenic pollution of fresh waters. In almost all industrial and urban areas of the world, the quality and supply of fresh water is declining. Therefore, providing the population and the national economy of Russia with it has become one of the most important socio-economic needs.
Decree No. 862 of October 18, 1992 “On urgent measures to ensure drinking water supply in the Russian Federation” obliged the relevant ministries and departments to take measures to improve the quality of drinking water and increase the reliability and sustainability of water supply systems for cities, towns and other water consumers (Medium Term Program, 1991). In this regard, large reservoirs of fresh water (eg, Lake Baikal) are of particular value.
Surface waters, which have the ability to self-purify, are more protected from pollution than groundwater (Kraynov et al., 1991). In connection with the growing pollution of surface waters, groundwater is becoming practically the only source of household and drinking water supply for the population. Therefore, their protection from depletion and pollution is of strategic importance.
The danger of groundwater pollution lies in the fact that the underground hydrosphere (especially artesian basins) is the ultimate reservoir for the accumulation of pollutants of surface and deep origin (Kraynov, Shvets, 1987). The most dangerous anthropogenic process of water pollution is the discharge of effluents from industrial-urbanized and agricultural territories; fallout of products of anthropogenic activity with atmospheric precipitation.
Pollution of endorheic lakes is also long-term and often irreversible. Enhanced and concentrated water withdrawal from the underground hydrosphere leads to the formation of extensive and deep funnels with soil failures, and a decrease in the level of surface waters.
A common feature of anthropogenic water pollution is a high concentration of toxic substances in local areas of the human habitat. In a number of regions, fresh waters have acquired anomalous geochemical properties (concentration of chlorides up to 15 g/l, nitrates up to 10 g/l, fluorides up to 3-5 g/l; these are environmentally dangerous concentrations). For organic compounds, some water systems have already entered the stage of irreversible changes (eutrophication), which increase with time. Such systems are capable for a long time hold high concentrations of pollutants.
Recently, the consumption of mineral, medicinal and table waters, as well as geothermal energy has increased dramatically. The reckless use of such resources without understanding the processes occurring in water reservoirs leads to tragic and costly mistakes. For example, in the famous Valley of Geysers in California, due to the large number of production wells, steam disappeared and the balance was quickly disturbed. To eliminate the crisis that arose in the 1970s. 3.5 million dollars were spent.
The brines of sedimentary basins attract attention as an important source of hydromineral raw materials and biologically active waters. Such brines have also been identified in the Timan-Pechora sedimentary basin. Practice shows that during the extraction of brines, irreparable damage is caused to overlying aquifers.
Studies in Russia and abroad prove a direct correlation between the quality (degree of pollution) of drinking water and human health. Widespread dental caries and fluorosis are due, respectively, to a lack and excess of fluoride in drinking water. F deficiency and caries are typical for the Karelian-Kola region and most regions of European Russia. In the 1960s a government decree was adopted on the fluoridation of drinking water with an F content of less than 0.5 mg / l. An excess of F and outbreaks of fluorosis have been recorded in Mordovia and Transbaikalia.
With a lack of iodine in water (especially among rural residents), thyroid diseases develop. Such regions are known in the Far North, the Urals, Altai, the North Caucasus, the Middle Volga region and in the north of the Russian Plain. Prolonged deficiency of I in drinking water leads to mental and physical retardation.
A link has been found between bladder cancer and drinking water with a high chlorine content. The most dangerous contaminants in drinking water include chlorinated hydrocarbons and dioxins (highly toxic persistent organochlorine compounds).
In agricultural areas, water accumulates pesticides. The list of human diseases due to its use is very wide. Of particular danger is water pollution by pathogenic microorganisms that cause outbreaks of epidemic diseases in humans and animals. The cause of most epidemics is the consumption of poor-quality water.
Oil spills have a negative effect on animals, fish, birds, and plankton. In the Republic of Komi, oil pipeline accidents most often occur. Oil turns water black, sharply reduces the amount of dissolved oxygen, causing the death of organisms. Groundwater is not able to oxidize a huge amount of incoming organic matter (oil), pollution becomes irreversible (up to the appearance of fuel oil lenses).
With the introduction of methane, heavy hydrocarbons and hydrogen sulfide, a reducing anoxic environment is created in natural waters, destroying hydrobionts.
Biological processes associated with the vital activity of algae, plankton, bacteria and other microorganisms (eutrophication of water bodies) can be environmentally hazardous.
Algae, plankton and micro-organisms play a role in both pollution and self-purification of natural waters. various fungi, yeasts, halophilic sulfate-reducing, methylotrophic, methanogenic and other bacteria are known to be present in water of various temperatures and salinities.
Long-term monitoring of the quality of surface waters shows that the concentrations of nitrogen, carbon compounds, and, to a lesser extent, phosphorus and heavy metals, have increased in them all over the world. Nitrogen compounds are highly soluble; their concentration in water can freely increase. Nitrogen transforms its migration forms depending on the temperature, redox conditions of the underground hydrosphere; some of its highly soluble forms pass into others and accumulate in a new geochemical setting. This adaptability of nitrogen to any geochemical situation determines the extremely wide range of its water migration.
Groundwater does not have nitrogen buffering capacity. The rate of natural denitrification of groundwater by bacteria is very low. Therefore, in the agricultural regions of the Komi, the waters of the upper aquifers turn from hydrocarbonate into nitrate-hydrocarbonate (saline).
Also, when excess fertilizers are applied in surface waters, the content of phosphorus increases (a favorable factor for the eutrophication of lakes and swamps).
7.3. Quality control of fresh waters. The quality of natural waters is assessed by comparing the pollutants present in them with their MPC or EIA for objects of household, drinking, cultural and household water use.
Such indicators are designed not only to detect an excess of pollutants, but also a deficiency of vital chemical elements (eg Se). The normative approach is the initial step in assessing the state of water, allowing you to quickly and cost-effectively identify priority pollutants and develop practical recommendations to reduce the negative effects of pollution. All countries have drinking water quality standards.
However, the normative approach does not take into account the combined effects (synergism or antagonism) of substances. This is especially true when these substances are present in concentrations close to the MPC, and when water is consumed for a long time.
It has been established that the long-term effect of low doses can be more detrimental to the population of aquatic organisms than an acute short-term toxic effect.
In addition, each body of water is unique due to large differences in chemical composition, mixing rate, temperature regime and vertical stratification. water masses. The normative approach in setting MPCs is not sufficiently based on experiments.
Reliable prediction and condition assessment water system complicated by the simultaneous impact on the system of many variable natural and anthropogenic factors; complex physicochemical and microbiological processes occurring in the aquatic environment.
To understand such processes, it is necessary to take into account the chemical interaction "water - bottom sediments" (especially in the case of fluid inflow into water or accumulation of heavy metals in lake silts). An important role in water chemical reactions of compounds of carbon, sulfur, nitrogen and phosphorus, redox potential has also been established.
The best way to obtain empirical data on processes in the aquatic environment is hydrogeochemical mapping followed by justification of the monitoring network. The information collected in the course of long regime observations serves as the basis for forecasting the state of the water system over time.
Currently, for environmental forecasting, computer modeling of hydrogeochemical processes of surface and groundwater pollution is used, which involves huge amounts of data in the field of study and makes it possible to obtain qualitatively new information.
Bibliography
Krainov S.R., Shvets V.M. Geochemistry of underground waters for household and drinking purposes. M.: Nedra, 1987.
Krainov S.R., Voigt G.Yu., Zakutin V.P. Geochemical and ecological consequences of changes in the chemical composition of groundwater under the influence of pollutants // Geochemistry. 1991. No. 2.
Kurennoy V.V. , Pugach S.L., Sedov N.V., Rachkov M.M. Problems of concentrated exploitation of underground waters // Geol. bulletin center. regions of Russia // 1999. No. 3.
Medium-term program (1997 - 2001) of rational use and protection of water resources of the Russian Federation. M., 1991. Issue 1.
Guidelines for drinking water quality control. Volume 1. Recommendations. WHO, Geneva, 1986.
Handbook of maximum permissible concentrations of harmful substances in food products and habitats. M., 1993.
Physical geography. M., 1991. S.56-65.
Nebel B. Environmental Science. M.: Mir, 1993.V.1. P.229 - 248.
Similar abstracts:
The relationship between the lithological features of the rocks of the coal-bearing strata of the Donbass, established by geophysical methods, and their chemical composition has been studied.
For areas of oil and gas fields, we study gaseous sorbed hydrocarbons and “other” gases as indicators of technogenic loads on natural environments.
Criteria for assessing the quality of natural waters and methodology for its study.
The ecological state of the environment is known to be influenced by both natural and anthropogenic factors. The former include the intensity of exogenous processes and phenomena, as well as the natural protection of underground and surface waters.
Municipal solid waste (MSW) landfills are dangerous sources of environmental pollution. Especially those of them that are not equipped with an impervious screen and are operated without proper insulation.
In open pit coal mining, mines leave patches of land that can no longer be used, thereby leaving scars on the surface of the earth. Rehabilitation can mitigate some of these problems.
Technogenic impact on the geological environment associated with the constantly growing volume of non-processed rock mass / about 100 mln. tons annually / has created a very tense environmental situation in a number of regions of the world.
The structure of the hydrosphere. Interaction of surface and ground waters. Formation of the hydrochemical composition of groundwater. Technogenic impact on groundwater.
; highlight environmental problems and ways to protect water; develop speech, attention; to cultivate a careful attitude to water, to reservoirs, the desire to save fresh water.
Equipment: schemes "The ratio of salt and fresh water", "Water is an important substance for the body", a recording of the song "Live, spring!", proverbs and sayings famous people, scientists about water.
Lesson progress
I. Presentation of the topic of the lesson.
Teacher. Hello guys! Listen to the riddle and guess:
They drink me, they pour me, everyone needs me. Who am I? (Water.)
– Today we will talk about water, about careful attitude to it. The topic of our lesson is “Mother Voditsa is the queen of everything. Why should water be conserved?
II. Water and life.
Teacher. Have you heard of water? They say she's everywhere.
First drop. In a puddle, in the sea, in the ocean,
And at the faucet.
Like an icicle freezes
Creeps into the forest with mist.
Second drop. It's called a glacier in the mountains,
Ribbon silver curls.
Among tall slender firs
Collapsed by a stream of mudflows.
Third drop. Boiling on the stove
The steam of the kettle hisses,
Dissolves sugar in tea.
Teacher. We don't notice it
We are used to the fact that water -
Our companion always.
droplets (together). You can't wash without me
Do not eat or drink!
Teacher. I dare to tell you:
We cannot live without water.
Thanks to our daily handling of water, we are so accustomed to it and to its various manifestations in nature that we often do not notice the distinctive properties of water. But it is precisely these properties that explain the fact that our lakes and rivers do not freeze to the bottom in winter, that strong spring floods are relatively rare, that freezing water can cause great destruction, etc. Many natural phenomena familiar to us are associated precisely with the characteristics of water distinguishing it from other substances.
The role of water in technology is also great. It is impossible to imagine such a branch of industry, where water would not be used in one form or another, for one purpose or another. Water serves as a source of energy. Water carries heat. Water is used as an excellent solvent for many substances. Water is the medium in which a huge number of different chemical processes take place.
In the history of our planet, water is also extremely important. Perhaps no other substance can compare with water in its influence on the course of those greatest changes that the Earth has undergone over many hundreds of millions of years of its existence.
Where there is life, there is always water. Life without water is impossible. Whatever animal or plant we take, it includes water as one of the main constituent parts. Inhabitants of reservoirs, as a rule, contain more water than land dwellers. In the body of fish, for example, up to 70–80% of water, and in a jellyfish - more than 95%. In herbaceous land plants, the percentage of water reaches 85. The organisms of mammals and humans contain less water.
If a person weighs 60 kg, then his body contains about 40 liters of water. During the year, each organism consumes an amount of water that is many times its mass.
A diagram is posted on the board.
Water is an important substance for the body:
for 1 kg of the body of a cow - 600 g of water;
ducks - 700 g of water;
a jellyfish has 99 g of water per 100 g of body.
Nutrients enter the blood through the walls of the alimentary canal. Only substances dissolved in water can penetrate through these walls, only liquids. If a lump of sugar had not dissolved in saliva and gastric juice, sugar would not have entered the bloodstream. Egg protein, bread and potato starch do not dissolve in water, but gastric and intestinal juices contain special substances - enzymes that break down protein and starch and convert them into soluble substances. This splitting occurs only in water. Blood, which is four-fifths water, carries nutrients throughout the body. Thus, water is needed for our body as a solvent for nutrients, and as a carrier for them, and as an environment in which various processes related to our life activity take place. Released by the sweat glands and evaporating from the surface of the skin, water regulates our body temperature. In addition, water is necessary to remove various harmful substances from the body that are formed as a result of metabolism. The water content in individual organs and tissues of the body is almost constant.
The need for water in different animals is not the same. Some of them are content with very small amounts of water, while others, on the contrary, require water in abundance. The granary weevil, for example, spends its life in dry spilled grain, in which there is only about 12% moisture. This insect, eating dry grain, probably even retains some of the water that is excreted in its body, as in any other, in the process of metabolism and respiration.
Another thing, for example, aphids. They feed on plant sap. To get enough food, they must pass a large mass of water through their body. The body of the aphid is designed so that the water in it does not linger for a long time and leaves the body, giving way to new portions of nutritious juice.
No living being can live in a completely dry space and cannot remain alive without water. Each organism can lose only a very certain part of the water it contains. In humans, the loss of 10% of water causes a number of disorders, and the loss of 20% of water causes death. Some animals are less sensitive to water loss.
Almost the same role as in animals, water performs in plants. Water delivers nutrients to plants from the soil and to a certain extent regulates the temperature of plants; evaporating from the surface of the leaves, it protects them from overheating in the summer heat.
Starting from the moment of seed germination, the plant must receive moisture all the time; for example, one sunflower plant needs about 40 liters of water during its entire growth, and alfalfa, creating one gram of dry matter, “drinks” about 500 g of water.
Plants get all the water they need from the soil. Plant roots suck water out of the soil with great force. This force is so great that, for example, in a nettle it would be enough to raise water to a height of more than 4 m, and in a vine - to a height of 13 m. Thus, land vegetation, pumping water out of the soil, acts as a powerful pump . From the roots, water rises to the stem and leaves and evaporates from their surface.
IV. Importance of water in nature and in human life.
Teacher. How wonderfully great people spoke about water! Aksakov called it the beauty of nature, Mendeleev - the blood of nature.
A person will somehow manage without oil, diamonds, invent new engines, but without water he will not be able to live. People have always deified water. There is not a single nation in which water would not be considered the mother of all living things, a healing and cleansing power, a source of fertility. The famous French writer - pilot Antoine de Saint-Exupery, whose plane crashed in the Sahara desert - wrote this: “Water! .. You have no taste, no color, no smell, you cannot be described, you are enjoyed without knowing what are you! It cannot be said that you are necessary for life: you are life itself. You fill us with a joy that cannot be explained by our feelings. With you, the forces that we have already said goodbye are returning to us. By your mercy, the high springs of our hearts begin to seethe in us again. You are the greatest wealth in the world ... "
- Guys, read the sayings of great people about water.
Water was given the magical power to become the juice of life on Earth. (Leonardo da Vinci.)
A drop of water is more precious than gold. (D. Mendeleev.)
There is no better drink on earth than a glass of cold clean water. (V. Peskov.)
Save yourself, man,
Son, dear, save!
So that rivers flow, not speeches
According to our great Rus'.
M. Rudakov
- Explain these statements. What are they about?
Teacher. All peoples treat water with care and respect. Read the proverbs different nations. They lived far apart, but everyone valued water.
Water is a mother, and you cannot live without a mother. (Chinese proverb.)
We do not value water until the well is dry. (English proverb.)
Drop by drop, a lake is formed, and if it stops dripping, a desert is formed. (Uzbek proverb.)
Russian proverbs:
And they drink muddy water in adversity.
Don't spit in the well: you'll get drunk.
Without dew, grass does not grow.
IV. Where did the water come from?
Teacher. If you quickly unwind the globe, it will seem that it is one-color, blue. Why? What is shown in blue on the globe? Where is the most water on Earth? (The seas and oceans are filled with water.)
Can a person use this water? (No.)
- Why? What kind of water do we need? (Fresh.)
Guys or kids?
All living creatures are completely happy!
3rd student. But what is? Guard!
No, no, nobody drowned
No, no, just the opposite
A steamship runs aground
In broad daylight, what a scandal!
Probably the pilot gave a blunder!
No, far from the buoy,
The river was deep here.
4th student. Was. That's right - it was.
There was, yes, apparently, swam.
Oh, we don't recognize the river...
The river becomes a stream!
Already the boats are aground ...
The swimmers suddenly went dry.
What about fish? In sorrow and sorrow
The poor things are fighting on the sand.
So what happened to her, to the river?
Alas, my friends, the answer is:
Preschooler Sidorov Ivan
I forgot to turn off the faucet in the kitchen.
You say: what a trifle.
Trifle. Good would the stream dry up,
And then out because of a trifle
The whole river is gone!
B. Zakhoder
Why did the water suddenly disappear in the river?
What happened after there was less water in the river?
What does this poem remind each of us?
Conclusion: Do not waste water in vain! Take care of her!
VII. Summary of the lesson.
Teacher. How should children and adults behave so that rivers and streams do not disappear?
Why should water be conserved and protected?
Water is part of every organism.
Water is life, beauty and health.
The amount of water is limited.
Water is the helper of man.
The water is polluted.
Student. Do not pour water in vain, know how to cherish water.
Close the faucet tightly so that the ocean does not flow out.
Teacher. What can the ocean ask us for?
Student. If the ocean could think, speak, it would say to a modern person: “How untidy you are, what a slob you are! You even managed to pollute me. Now you have to clean me. I don’t know how you will do it, but you must do it, otherwise you will pay yourself: it will be bad for you and your descendants.
Teacher. After all, it is not for nothing that the ocean would say so: it is littered. Anything is dumped into it. In the northern part Pacific Ocean floats about 5 million old rubber sandals, approximately
35 million empty plastic bottles and about 70 million glass floats. All of these items are non-degradable. If not caught, they will float for hundreds of years. Let's read the commandments:
1. Our planet is our home, and each of us is responsible for its future.
2. If you find a spring in the forest, save it. Maybe this is the beginning of a large full-flowing river.
3. Listen to the murmur of the river. Maybe she asks for help from you and she needs your caring hands.
The spring smelled of earth, grass and pine needles,
It's always cold on a hot afternoon
And put your hand in blue -
Light water caresses.
At his thoughtful singing
I studied cleanliness a lot,
The first, most timid inspirations,
The first, most joyful dream.
Let away from the low house
I, manly, will become gray-haired,
I will still come to him, alive,
And I'll drink his water.
V. Soloukhin
The song "Live, spring" sounds.
Protection and protection of natural waters
The protection and protection of natural waters should be understood as a system of measures aimed at preventing and eliminating the consequences of pollution and clogging of surface and groundwater. To protect surface water from pollution, various measures are taken. The most significant of them are the following: - improvement of technological processes in industry to reduce water consumption and create circulating water supply systems; - ensuring complete biological treatment of wastewater from industrial enterprises and populated areas; - rational water use in agriculture, including the validity of the use of fertilizers and pesticides, as well as farming within the catchment area; - compliance with environmental standards for the extraction and processing of minerals, their enrichment and transportation; - compliance with the rules for drilling and construction works (where they are carried out) in water protection zones; - reduction (and, if possible, prevention) of biogenic elements (nitrogen and phosphorus) entering water bodies; - observance of water protection zones and rules of economic activity in them; - ensuring constant monitoring of the state of water bodies and indicators (standards) for the composition and properties of water quality; - development and implementation of low-waste technologies. Preventive, organizational and technical methods contribute to the improvement of surface water quality. One of them is self-purification, which is possible due to the activity of higher aquatic plants (bulrush, cattail, narrow-leaved reed, duckweed, algae), which saturate water with oxygen (since the content of calcium and magnesium ions decreases under the influence of oxygen in water). The essence of this method is to maintain and restore water bodies. In recent years, plants (water hyacinth, pistia, calamus, water pine, pondweed) have become widely used for deeutrophication of polluted water bodies, which provide a significant increase in biomass (up to 100 kg/m2 per month), and, accordingly, a decrease in pollutants. One of the essential measures for the protection of surface waters from pollution is the observance of the boundaries of water protection zones, which are important protective function on any water body, especially on small rivers, which make up over 95% of watercourses in Russia. These zones include: river floodplain, floodplain terraces, crests and steep slopes of bedrock banks, areas of eroded land, gullies with a length of more than 10 km or any length, but with a slope steepness of more than 8 °. Under the protection of groundwater is understood a set of measures aimed at preserving and improving such a qualitative and quantitative state of groundwater, which allow them to be used in the national economy. Groundwater protection consists in strict observance of water legislation, provides for a set of preventive measures and special water protection measures, which are divided into preventive and special ones. Preventive measures include the following: choosing the location of the facility (industrial, agricultural) with minimal impact on the environment natural environment and groundwater; careful observance of sanitary protection zones of groundwater intakes, etc. Special measures include: construction of protective water intakes to intercept contaminated groundwater and hydraulic watersheds (veils) between the water area and exploited clean groundwater, as well as the creation of impenetrable screens (walls) around the outbreak pollution, etc. For groundwater, the main negative consequences of anthropogenic impact are pollution and depletion. Carrying out special protective measures is expensive, often a complex and cumbersome technical system, which includes the mandatory treatment of pumped contaminated water. It should be borne in mind that groundwater pollution is interconnected with the state of the environment: it is impossible to prevent their pollution if waste enters surface water, atmosphere, soil, since these components of the biosphere are closely related to the water cycle. Therefore, in the protection of groundwater, the most important are preventive measures that prevent their pollution. Groundwater depletion is understood as a decrease in their natural and (or) artificial reserves due to the excess of groundwater consumption over their supply. The reasons for such depletion can be deforestation, plowing of land, straightening and diversion of rivers, withdrawal of groundwater by water intakes, water-lowering installations, drainage, etc. At the same time, depletion can be temporary (seasonal) and permanent (due to economic activity) in nature. Replenishment of groundwater reserves is carried out: through the creation of dams, dams, dams, ponds that regulate the flow of watercourses or atmospheric flow; by pumping water from pressure horizons; snowmelt delays; thanks to the use of biochemically treated wastewater; reduction of evaporation; improving the methods of watering and irrigating farmland. At the same time, it should be taken into account that the sanitary authorities have established water quality standards for artificial replenishment. The irrational use of groundwater (as well as surface water) has economic, social and environmental impacts on both humans and nature. In the hydrosphere, as well as in the biosphere as a whole, the effect of the ecological postulate "everything is connected with everything" is clearly traced. According to the Water Cadastre in Russia, there are over 127 thousand rivers with a length of 10 to 200 km. Of these thousands selected about 600 rivers in need of protection. In order to avoid their pollution and depletion, mandatory water protection zones have been created or are being created along the rivers, in which it is forbidden to plow land, use pesticides, and graze livestock. The main task of water protection zones is to provide and maintain a favorable regime, improve the condition of small rivers and reservoirs, protect them from being flooded with soil erosion products, and avoid pollution by pesticides and biogenic substances. Protection of rivers and reservoirs from pollution can occur through their self-purification. For example, high-flowing rivers provide good mixing and lower concentrations of suspended particles. The settling of insoluble sediments in water, as well as the settling of polluted waters, contribute to the self-purification of water bodies. A decrease in water temperature favors the long-term preservation of bacteria and viruses entering water bodies. So, in the temperate climate zone, the self-cleaning of the river occurs in a section located 200 ... 300 km from the place of pollution, and in the Far North, the distance to this section increases to 2 thousand km. The physical factor of self-purification of water bodies is the ultraviolet radiation of the Sun, under the influence of which water is disinfected. Of the chemical factors of self-purification of water bodies, oxidation of organic and inorganic substances should be noted. Pollution of water bodies with chemicals leads to a disruption in the normal processes of water self-purification, a change in some important properties of microbes and, ultimately, a change in water quality. The biological factor of self-purification is the totality of organisms inhabiting water: bacteria, algae, various invertebrates, therefore it is so important to maintain conditions that make water suitable for their existence. The death of bacteria and viruses can contribute to some chemical substances and representatives of the animal world. So, oysters and some types of amoebae adsorb intestinal and other viruses, and the Dreissen mollusk, resembling the southern mussel in appearance, passes water polluted with organic scales through itself, mineralizes and precipitates unnecessary substances.
