Sewage treatment. Creating a biological pond to clean wastewater which there are types of biological ponds

Every year there is an increase in water consumption, which is associated with an increase in the number of residents of the majority of the country's regions, as well as the continuing growth of industry. This leads to the fact that environmental pollution by wastewater also increases, putting the experts a difficult task - as with the smallest losses for progress to cause nature as far harm. There is a need to develop effective wastewater treatment techniques, among the most efficient, these are the creation of biological ponds. We will get acquainted with them closer, learn the essence of this term, varieties and specifics of arrangement and application.

Concept

Now they are not rare. And the biological ponds relate to their number, but they are distinguished from other varieties. Purpose is distinguished - in such ponds, as close as possible to natural conditions, in which wastewater self-cleaning will be made. You can also meet other names of the facilities - lagoon, simple ponds, stabilization, ponds of cooktics.

The main "residents" of such water bodies are green algae, which actively distinguish oxygen during their livelihoods, and this chemical element, in turn, leads to the acceleration of the decay of the organics. In addition, the following groups of factors affect the decomposition process:

• Temperature.
• Aeration.
• Water speed.
• Life of bacteria.

Thus, water purification occurs - completely natural and pretty quickly. In just 5 days, it is possible to complete the water purification. In addition, plants will accumulate inside themselves heavy metals, which are exposed to decomposition for a long time.

Characteristic

We will get acquainted with the basic parameters of biopudov:

• The optimal depth is small - from 0.5 to 1 meter.
• Form - rectangle.
• The ratio of length and width depends on the method of aeration: if it is artificial, then the proportion is 1: 3, if natural is 1: 1.5.

It is in such conditions that the mass development of plankton algae and other useful microorganisms occurs. To perform their direct functions, such plants are planted next to them: reeds, AIR, reed, violated, water hyacinth and some others.

The duration of the useful use of these structures is more than 20 years.

Varieties

Biological boards for water can be three main species, information about them for the convenience of perception is presented in the table format.

In addition, you can meet a different classification - division on flow and contact, while the first, in turn, can be a lot and single-stage.

Also, biopruses can be divided into three groups depending on the biotic cycle: anaerobic, aerobic and elective-aerobic.

• Anaerobic is most often used for partial water purification. Living organisms living in them need large amounts of oxygen. The essential point of such water bodies are unpleasant smells of rotting.
• The aerobic are the most powerful purification, since living organisms living in them are primarily algae, take part in the oxidation of wastewater.
• Facultative-aerobic - an intermediate version that combines the unpleasant smell of rot and more efficient cleaning.

With multi-stage cleaning in the ponds of the last stage, the fish may be divorced, most often it is carp.

Application

Studies have proven that the easiest and most effective water purification system is the use of natural methods, in particular, vegetable organisms. For algae, improving water quality is a natural function, because for normal life activity, they need potassium, phosphorus and nitrogen, and microorganisms are formed in the root system responsible for the oxidation of the organicities. On these factors, the work of artificial reservoirs is based.

Biopruses are used both for self-purification of water and as part of a whole complex of such structures, for example, anticipating the use of agricultural fields of irrigation or to clean at aeration stations. To clean wastewater, biological ponds are preferably used in those regions where the air temperature is at least +10 ° C on average during the year and moderately humid climate.

Sanitary supervision

Claimed facilities, including biopruses, are under constant sanitary control, the task in the implementation of which is carried out by SanEPIDs. The following specialists are required to control the condition of such water bodies:

For the purpose of control, various types of research are used, including bacteriological. It is also checked by observance of measures to prevent wastewater relief, not subjected to pre-cleaning and disinfection in reservoirs.

Benefit

Biological water purification in the pond, in addition to its simplicity and performance, it is also very useful to a person. First of all, conventional natural processes are used, so there is no speech about artificial interference with the natural community. Such reservoirs can be used both for self and for doctor. In addition, biopruses help in the following cases:

• Destroy up to 99% of the intestinal sticks.
• It decreases almost up to 100% the maintenance of helminth eggs.

However, it is important to note the substantial minus of such water bodies - at low temperatures, the efficiency of their use is reduced at times, and they can no longer perform their functions: the oxygen does not penetrate into the water, therefore the process of oxidation of the organic.

The use of biopuds - water bodies in which living organisms live - is the simplest and most advantageous system of biological purification of the pond. This method helps to achieve significant energy savings and resources, and the result will be very high-quality. In addition, compliance with any special conditions is not required, the care of the construction is most simple as possible.

Biological ponds are artificially created reservoirs for biological wastewater treatment, based on processes that occur in self-cleaning of water bodies

In the absence of well filtering soils for the device of filtration fields or irrigation fields, the ponds can be used as independent structures for wastewater treatment, as well as for their octopic, in combination with other sewage treatment facilities.

Ponds make a small depth - from 0.5 to 1 m. This allows you to create a significant surface of the contact of water with air and ensure warming up the entire thickness of water and good mixing it. Thus, favorable conditions are created for the mass development of aqueous organisms, in particular plankton algae, which assimilate biogenic elements and as a result of the synthesis process enriches water with oxygen necessary when organic substances.

Biological ponds Provide a higher effect of bacterial self-cleaning than structures of artificial biological purification. Thus, the number of intestinal sticks in the ponds decreases sh. 95.9- 99.9% of the initial content. The maintenance of the eggs of helminths in the water, which has passed the biological ponds, is negligible.

Wastewater cashing and the removal of purified water from ponds is dispersed.

For the possibility of complete emptying of the ponds, the bottom of them should be attached to the direction towards water-felled facilities.

The normal operation of the ponds occurs in the warmth time, and already at the temperature of the water below 6 ° C sharply deteriorates.

With a further decrease in temperature and especially after the formation of ice cover, when the oxygen penetration into water does not occur, the process of oxidation of the organic matter almost completely stops. During this period, only the wetting of wastewater may occur.

Biological ponds are usually calculated by load on the surface depending on the concentration of pollution and temperature conditions.

Distinguish the following types of biological ponds: 1) dilution ponds (fish); 2) ponds without dilution (multistage or serial); 3) Ponds for wastewater doctors.

In the first case, wastewater after preliminary clarification in sumps is mixed with fresh river water in proportions 1: 3-1: 5 and sent to single-stage flowing ponds, where the process of oxidation of the organic matter is. The load of the wastewater is 125-300 m3 / (whatever day). The size of each pond is 0.5-7 hectares. Duration of water stay (taking into account dilution) 8-12 days. In the ponds you can breed fish.

In the second case, wastewater after pre-settling is sent to a pond without dilution with clean water. Such biological ponds were first arranged on the initiative of prof. S. N. Stroganova at the Moscow Filtering Fields.

The duration of wastewater purification in the ponds of this type is greater than in the ponds of the first type; Water exchange occurs for a period of up to 30 days. The loading of the wastewater is about the same as in the ponds with dilution [in Moscow 125-150 m3 / (Ma-day)].

Construction and operational costs in the device of ponds without dilution are significantly less than when the device is diluted with dilution.

In order to ensure proper water purification, the ponds without dilution are arranged in 4-5 steps (serial ponds), which water passes consistently. The degree of purity of water with each subsequent step is gradually rising. The ponds of each stage usually have an area of \u200b\u200b2-2.5 hectares.

The lower levels of serial biological ponds without dilution can be used to breed fish, mainly carp.

In the breeding of fish in early spring, the pond produce 500-2000 fry per 1 hectare. The growth of fish is by the end of the autumn period to 500-800 kg per 1 hectare. Fish fish is made late autumn.

The presence of a large mass of nutrients in water contributes to the intensive growth of algae (ore). To combat them, it is desirable to breed in fish-water ponds of ducks, for which the rod is a good feed.

During the device of biological ponds, land plots are more fully used than with the construction of irrigation fields or filtering fields. In addition, ponds can be arranged on such soils that are unsuitable for fields.

Waste waters that have passed biological ponds can be used for irrigation. In this case, watering machines, liman irrigation, long furrows, sprinkled irrigation can be used.

If necessary, on the local conditions of increased wastewater treatment for their fines (after artificial treatment plants), it is recommended to arrange a third-type biological ponds. The number of steps in such ponds should be: when the biologically purified waste water supply is admitted in them, during the admission of abstinal wastewater - 4-5 steps. The load on the ponds should be taken in view of their reaucascence, which gives 6-7 g of oxygen per 1 m2 pond. This is enough to ensure cleaning 100-250 m3 / (whale-day) wounded wastewater (without dilution) or 4000-5000 m3 / (ha-s) of biologically purified wastewater.

Ponds designed to clean wastewater can also be used for fishing. In these cases, the device of additional small ponds should be provided with a depth of at least 2.5 m for staying in them in the winter.

Recently, a pond with photosynthetic organisms of phytoplankton is obtained to purify wastewater, in particular with chlorella alga.

To categoriarity: Sewage treatment

Biological wastewater treatment in vivo

Biological wastewater treatment in natural conditions can be carried out in biological ponds, on the fields of filtration and underground filtering facilities, as well as on agricultural irrigation fields.

Biological ponds - artificially created shallow reservoirs, in which biological wastewater treatment occurs on weakly filtering soils, based on processes occurring in self-cleaning of water bodies. Biological ponds can also be used to purify wastewater after passing through other structures for biological purification. Ponds are single (small non-flowing depth of 0.6-1.2 m) or consisting of three-five ponds, through which the waste liquid is slowly leaked in biofilters.

To clean wastewater in the IV climatic area, biological ponds can be used all year round, in the II and III climatic areas - only in the warm season, and in the cold season, provided that the water in bioprud has a temperature not lower than 8 ° C.

Cleaning wastewater in biological ponds can occur in anaerobic and aerobic conditions. Anaerobic ponds have a depth of 2.5-3 m, the load on the BOD for household wastewater is 300-350 kg / / / (g-day). Aerobic biopruds with natural aeration can be used to clean wastewater with a concentration of BPK.5 not higher than 200-250 mg / l in the IV climatic zone year-round, and in the II and III climatic zones - only in the warm period. The estimated load on the ponds for wandering waters is taken up to 250 m3 / (GA-day), for biologically purified water - up to 5000 m3 / (GA-day). With a pond area of \u200b\u200b0.5-0.25 hectare, the time of sewage residence depending on the load ranges from 2.5 to 10 days.

It is advisable to exercise bancoles for complete cleaning, taking the degree of cleaning in each of the steps to 70% in each of the steps. To intensify the process of cleaning wastewater into biopruses, an oxygen of air is supplied with artificial means. Such biopruses occupy a significantly smaller area and less depend on climatic conditions, they can work at air temperature from -15 to - 20 ° C, and on some days to -45 ° C.

Studies of Vnies Vygogo, Misi. V.Kuibyshev and TsNIIEP of engineering equipment, as well as the results of production tests of the Belarusian Research Sanitary and Hygienic Institute confirmed the expediency of using the aerated biopuds for wastewater treatment in rural areas of 100-10 000 m3 / day, and for the purification - to 50 000 m3 / day.

Aerial biopruses can be used to clean wastewater with a concentration of BPK5 to 500 mg / l, they provide efficient wastewater treatment in II and III climatic zones. In the northern regions of the II climatic zone, as well as in areas with sustainable winds in the winter season, it is more advisable to use biological ponds with a recycling cycle (return) of the catch mixture having the best heat engineering characteristics. Before the bioprudes should be provided for mechanical wastewater treatment. At the concentration of suspended substances up to 250 mg / l, the settling time can be taken equal to 0.5 hours, at a concentration of 250-500 mg / l - 1 h.

Fig. 1. Plan of the station of biological wastewater treatment with a bandwidth of 700 m3 / day 1, 2, 3, 4- aerated ponds, respectively, I, II, III, IV steps: 5 - pond-sump; 6 - contact pond; 7 - production building: 8 - suction pipeline of technical water; 9 - air duct; 10 - pressure pipeline of technical water; 11 - receiving chamber; 12 - Supply pipeline with a diameter of 300 mm; 13 - bunk sump; 14, 17 - sands; 15 - sandbag; 16 - Ilovaya courts

On the construction of wastewater treatment facilities, the lowest capital investments are required compared to the cleaning of other methods. Specific costs at these stations are 20-50% lower. In addition, the aerated biopruses are characterized by a high level of mechanization of earthworks and the minimum consumption of reinforced concrete and other building materials.

Filtering fields can be used in some cases if there are unsuitable for agricultural use of land plots with filtering soils, in the absence of risk of groundwater pollution used for drinking needs. Land portions of filtration fields are specially prepared for biological wastewater treatment, preventing their use for agricultural purposes. The seed water supplied to the fields enters separate areas (maps) on the system of open trays or channels (adjustable channels); The complex of these channels is the irrigation network. The collection and removal of the filtered purified water is carried out using a drainage, which can be open in the form of a canvas around the perimeter of cards or closed, consisting of drainage pipes, laid on a map at a depth of 1.5-2 m, and a canvas. The drainage and canvas system forms a drying system. Channels are made of bricks, boot, reinforced concrete, concrete or made by earthen. Channels have a rectangular or trapezoidal cross section; Place them by protective earth rolls.

When designing filtering fields, open areas that are not flooded with spring waters with a calm terrain with a natural slope of not more than 0.02 are chosen. For the device of filtration fields, areas are not suitable, located close to the seeding of aquifers, as well as peat and clay soils and salt marshes. The most suitable sandy and sampling soils. The fields are recommended to be located from a leeward side at a certain distance from residential arrays, depending on the flow of wastewater: at a flow rate of up to 5000 m3 / day, this distance is taken by 300 m, at 5000-50 000 m3 / day -500 m and over 50,000 m3 / day -1000 m. According to the contour of the fields, IVI and other moisture-boring plantations are usually planted. The width of the space of plantings takes 10-20 m, depending on the remoteness of fields from the settlements.

Household wastewater, purified in the filtration fields, have a BOD 10-15 mg / l, a resistance of 99% (i.e. do not rot), contain nitrates up to 25 mg / l. The number of bacteria decreases by 99-99.9% compared with the content of them in its original water. Special disinfection is not required. For successful operation of the fields, it is necessary to supply wastewater on them, pre-clarified, i.e. To a large extent freed from suspended particles. In addition, when upholding up to 50--80% of helminths is distinguished from the waste liquid, which reduces the soil contamination of 7-10 times.

The required area for filtration fields is determined based on the load rate - the permissible amount of wastewater, which can be cleaned by 1 hectare of the fields. In addition, the nature of the soils, the groundwater level and the average annual temperature on load standards are taken into account. The load standards of the clarified wastewater on the filtration fields for areas with an average annual precipitation of 300-500 mm are shown in SNiP 2.04.03-85.

For the device of fences of cards, irrigation network, roads and entry on cards, it is necessary to provide for additional area. Thus, with a utility area of \u200b\u200bfiltration fields up to 0.3 hectares, an additional area is provided for 100% of the useful area, at 0.5 hectares, at 0.8-80, at 1 heater and 60 and more than 1 Ga- 40% of the useful area Fields.

When filtering fields usually provide constant and temporal irrigation networks. The permanent irrigation network (Fig. 2) consists of a mainstream channel, group distribution channels and cardan rods serving individual cards. Cartovyn Irrings - the last element of the constant network.

Fig. 2. Scheme of irrigation fields 1 - trunk and distribution channels; 2 - Narovy rods; 3 - Draisual ditch; 4 - drainage; 5 - expensive

The irrigation network is designed from ceramic or asbestos-cement pipes with a diameter of 75-100 mm. It is allowed to use irrigation trays of brick, concrete and other materials. Put irrigation pipes in sandy soils with a bias of 0.001-0.003, and in the suction - horizontally. The distance between the parallel irrigation pipes in the sands of 1.5-2.0 m, in the soup-2.5 m. Ceramic pipes are paved with gaps 15-20 mm; Over the joints of pipes should include overlays. In asbestos-cement pipes of irrigation networks, cuttings are made on half diameter with a width of 15 mm. The distance between the propuls should be no more than 2 m. For air intake at the ends of irrigation pipes, the risers are set with a diameter of 100 mm, towering 0.5 m above the ground surface.

Fig. 3. Diagram of device of underground filtering fields 1 - release from the building; 2 - three-chamber septic tank made of reinforced concrete rings; 3 - dosing chamber with metering siphon; 4 - Distribution chamber; 5 - drain

The drainage network in the filtration fields are provided with adverse ground conditions. It consists of drainage, a national network, reducing lines and issues. The drainage system is an integral part of the fields, as it allows the soil excessive moisture timely and contributes to the penetration of the air into the active layer, without which the aerobic oxidative process cannot pass. In the lowered soils (Sugorlinka), closed drainage are built, in permeable soils (sands, sandy) drainage or is not required at all, or they are satisfied with the open drain duals.

The distance between the drains depends on the degree of water permeability of the soil, the depth of the drying layer, the depth of the drain, the amount of water returned, etc. For preliminary calculations, the distance between the drains in the sands takes 16-25 m, in the Supayes 12-15 m and in the lungs of 8-10 m. In coarse sands, in some cases, drainage is built in the form of open discrepancies with a distance between them up to 100 m.

The closed drainage is suitable mainly from the unhappy pottery pipes with a diameter of 75-100 mm.

The drain should be placed perpendicular to the direction of the stream of groundwater with a slope of 0.0025-0.005. There are 4-5 mm gaps between the pipes. Under the joints, the clay pillow is placed on top of the joints overlap the tale or felt. Open discharge dials, prefabricated networks and issues are arranged in the form of channels of trapezoidal shape with side walls at an angle of natural slopes.

In winter, after draining the soil, the sewage filtering on the filtration fields is significantly slowed down, and sometimes completely stops, and wastewater is frightened to the fields. Therefore, in areas with a cold and temperate climate, the filtering field should be checked for marching. Typically, the height of the wastewater waste layer is taken 0.6-0.8 m, in accordance with which the height of the shafts enclosing the card is determined.

Construction of underground filtering. For cleaning small amounts of sewage, underground filtering fields are used. Water water from a building or group of buildings is sent for pre-lightening to septic tank (Fig. 3). The clarified water enters the network laid at a depth of 0.3-1.2 m pipelines with unknown joints, through which the wastewater penetrates into the ground, where its further cleaning occurs. Purified wastewater is not assembled into the drainage network, but seeps into the thickness of the soil or partially leaving the ground stream.

In the territory of the fields of underground filtration is allowed to grow garden crops. The lack of filtering fields is the need for a wide sanitary break zone (200-300 m). For objects with wastewater consumption of up to 12 m3 / day in some cases (in the presence of filtering soils, deep groundwater supply and the absence of the risk of pollution of the aquifers used for drinking water supply) Claimed treatment facilities operating on the principle of underground wastewater filtration ( Sand-gravel filters, filter trenches, filtering wells). These structures are quite simple in construction and operation and are intended for complete biological cleaning.

The structures of underground filtration (in contrast to ground filtration fields) can be located near the buildings serviced by them and do not require the construction of an outdoor sewer network of considerable extent. Waste water on sewage treatment facilities is coming by self, and therefore the pumping stations are not required. Such structures are appropriate to arrange in sandy, samp and light lighter soils.

Sew water from the building or group of buildings is sent for pre-lightening into septic tank. The clarified water through the dosing chamber and the distribution well enters the drainage pipes located above the groundwater level of at least 1 m, or the filtering well. Through unknown joints and cuts of pipes or holes in the walls of the well, the clarified liquid enters the ground, where its further cleaning occurs. During the operation of underground filtration systems, air pollution and upper layers are eliminated.

Typical projects of treatment facilities underground filtering systems are designed in accordance with a unified number of such facilities of small productivity 0.5-12 m3 / day. The nomenclature of typical projects includes: septic tits; systems with underground filtration fields and filtering wells used in sandy and sampling soils; Systems with filter trenches and sandy-gravel filters used in drigly and clay soils.

Septic is an underground structure in which wastewater flows at low speed, while suspended substances fall into the precipitate, and the liquid is brightened for 1-4 days. The precipitate in the septic was subjected to long-term overjunction (fermentation) for 6-12 months under the influence of anaerobic microorganisms.

The calculated volumes of septicists should be taken from their cleaning conditions at least 1 time per year. Under the average winter sewage temperature above 10 ° C or at the rate of drainage of more than 150 l / (person-day), the full estimated septicity can be reduced by 20%.

At wastewater consumption of up to 1 m3 / day, one-chamber septic tanks are provided, up to 10 m3 / day - two-chamber and over 10 m3 / day - three-chamber. The volume of the first chamber in two-chamber septices is taken equal to 0.75; in three-chamber-0.5 calculated volume. In the latter case, the volume of the second and third cameras should be 0.25 computational volume. In septices from concrete rings, all chambers can be equal volume. With expenditures of more than 5 m3 / day, each chamber should be separated by a longitudinal wall into two identical compartments. Minimum Sizes Septic: Depth (from water level) 1.3, width 1, length or diameter 1 m. Maximum septic depth is not more than 3.2 m. Natural ventilation should be provided in septics. In a typical project, septic tanks are developed by the bandwidth of 0.5-0.25 m3 / day (Fig. 4).

The sandy-gravel filter is a pitual, which contains a filtering frustration. Depending on the number of layers of frustration, the filters are single and two-stage. In single-stage filters, coarse sand with a layer of 1 -1.5 m are used, in two-stage filters, the first stage is loaded with gravel, coke, a granulated slag layer of 1-1.5 m, the second one is similar to a single-stage filter.

The filtering trench is a constructive variety of sand-gravel filters - is dispersed and elongated filters. The trenches are used in cases where the sand-gravel filter device is not allowed due to the close location of groundwater and it is impossible to remove the drainage network due to the terrain. The calculated length of the filter trenches is taken depending on the flow of wastewater and the load on the irrigation pipes, but not more than 300 m, the width of trenches at the bottom is not less than 0.5 m.

In the filtering trenches, large-mediated sands and other coarse-grained materials with a layer thickness (between the irrigation and drainage pipe) are used as a bootable material with a thickness of the layer (between the irrigation and drainage pipes. Pipes of the minimum diameter of 100 mm are used for irrigation pipes and drains drains of filters and trenches, Putting them into the gravel (or from other coarse materials) with a thickness of 5-20 cm. The depth of the embodiment of irrigation pipes from the surface of the Earth should be at least 0.5 m. The distance between parallel irrigation pipes and between the discharge drains in sandy-gravel filters 1- 1.5 m. The slope of irrigation and drainage pipes in filters and trenches is at least 0.005.

Fig. 5. Cleaning wastewater in septic tanks and filtering wells 1 - sewer riser; 2- release from the building; 3 septic; 4 - drain pipe; 5 - Filtering Well

Filtering wells are designed to clean household wastewater coming from separately standing buildings at a calculated flow rate of no more than 1 m3 / day after pretreatment in the septic. They are used in sandy and sampling soils in the absence of sufficient areas for placing underground filtering fields and the location of the well of the well at least 1 m above the maximum level of groundwater (Fig. 5).

Filtering wells round in shape are performed from reinforced concrete rings with a diameter of no more than 2 m, and rectangular - from ampfully buried bricks and butt stones with a size of no more than 2x2 m in the plan and 2.5 m depth. Inside the well satisfy a bottom filter with a height of up to 1 m from gravel, rubble, coke, well-sided boiler slag and other materials. The outer walls and the base of the well perform a sprinkle from the same materials. In the walls of the well below the drilling pipe drilled holes for the release of filtered water. Wells overlap the stove with a hatch with a diameter of 700 mm and equipped with a ventilating pipe with a diameter of 100 mm.

The calculated filtering surface area of \u200b\u200bthe well is determined by the sum of the bottom area and the surface of the inner walls of the well to the filter height. The load on 1 m2 of the filter surface area in sandy soils is taken by 80 l / day, and in the sandy - 40 l / day. When the device of filtering wells in medium and coarse-grained sands or at a distance between the base of the well and the groundwater level, more than 2 m increases by 10-20% (the latter figure is taken at the rate of drainage per person more than 150 l / day or with the average sewing temperature Waters above 10 ° C). For seasonal objects, the load can also be increased by 20%.

The agricultural fields of irrigation, suitable on the lands of collective farms and state farms, are intended for year-round reception and disposal of wastewater in the process of their agricultural use. These fields have low load standards on 1 hecting irrigation area, as well as a small volume of planning work. The year-round sewage taking regardless of climatic conditions is possible if the load standards do not exceed 5-20 m3 / day per 1 hecting irrigation area. The agricultural fields of irrigation are located on the soils suitable for agriculture, or that can be used after properly preparation (amelioration). The natural bias of land plots should not exceed 0.03 (the most acceptable slope 0.005-0.015).

Urban wastewater at first enter the sewage treatment station, where it is pre-processed, i.e. there are grid, sandball and primary sumps. At night, water enters the regulatory containers. After sumps, the sewage is gravity or with pumps is supplied to the fields of fields.

On the territory of the fields, water is fed by an irrigation network, which is subdivided:
a) the constant, submitting wastewater to the fields of crop rotation and consisting of constant main and distribution pipelines stacked mainly from asbestos-cement pipes;
b) temporary, consisting of portable pipelines, time rods, nippers and drainage grooves;
c) irrigation, consisting of furrows, strips and subsorative humidifiers.

The pipelines of the constant irrigation network are laid taking into account the primer of the soil on the arable lands at a depth of 0.7-1.2 m, and under the roads and in the territory of populated areas lowering the depth of the primer of the soil by 0.1 m to the shells of the pipe. From a closed constant network, water is produced by special water. Watering wells depending on the terrain relief and the location of the irrigation sections with one-sided distribution are placed at a distance of 100-200, with bilateral -200-300 m.

Humidious and helpful irrigation norms of wastewater on agricultural irrigation fields are established depending on the composition of cultures and plantations, their needs in mineral food and water, sanitary and hygienic requirements related to wastewater disposal. The calculated water consumption is 5-20 m3 / day per 1 hectare or 1800-7300 m3 / year.

- biological wastewater treatment in vivo

Biological ponds, also called lagoons, are specially created shallow reservoirs, where the natural processes of self-cleaning of water are proceeded with the participation of their organisms inhabiting their organisms. Ponds can be used both independent cleaning systems and wastewater treatment after removal of the bulk of pollution. They are widely used to purify household wastewater, incoming most often at the undiluted form, and the finishing of wastewater companies of food and processing, pulp and paper and other industries, livestock farms, cleaning of surface (storm, wax) water, drainage of agricultural waters in conditions of irrigation agriculture. Purified water can be used in a circulating water supply system of enterprises, which reduces their overall water consumption.

Biopruses are divided into anaerobic, aerobicaeerobic (optionally aerobic) and aerobic, as well as high and low-loaded, flow and contact. Aerobic (oxidative) ponds can be with natural and artificial aeration. Single ponds and cascade of ponds can also be used.

Anaerobic conditions are observed in the presence of excess organic substances and lack of oxygen:

• In the ponds with loads on the BTG about 300 .. .600 kg / g-day;
• In the bottom layers of water in ponds, a depth of 2.5 m and more even when the water is saturated with oxygen in surface layers;
• in the contact (unusual) ponds in the first phases of purification after filling the pond with wastewater;
• In the spring, the autopsy of biological ponds with intensive decomposition of organic compounds accumulated in the winter.

In the cascade of flowing ponds, the head pond, which takes on the main mass of pollution, can also be anaerobic.

The processes of nitrate-duktion, sulfatered generation, methane fermentation, reduction of oxidized forms of metals and other substances lead to the decomposition of organic substances, precipitation of heavy metals sulfides, leading to anaerobic ponds. Operation of such ponds usually provides for the possibility of separating active rals from purified wastewater (in sumps, emissions). Anaerobic cleaning in ponds allows you to remove 80 ... 90% COD at 25 ° C (50% at 10 ° C) at the time of water stay in the construction of 40 ... 50 days, however, the content of pollution in water after anaerobic cleaning remains still High, therefore its further purification is required in the stage of flow aerobic ponds or, if the contact method is adopted, in the same pond, but in aerobic conditions.

In Russia, anaerobic ponds practically do not use low annual average temperatures and the formation of a large number of fuses in the functioning of such ponds.

Aerobo-anaerobic ponds have a depth of 1.5 ... 2 m and aerated due to natural processes. In the surface layers of water there is dissolved oxygen coming from the atmosphere or formed as a result of photosynthesis. The flow of oxygen due to atmospheric aeration is limited and does not exceed several grams of OG per 1 m 2 per day. The day photosynthesis enriches water with oxygen, and at night the oxygen is consumed in the process of respiration by animals and plants, while the oxygen deficiency may be observed in water. In the bottom layers, with the complete absence of oxygen, anaerobic processes, sulfate-generation, methane fermentation may occur. In such ponds, the precipitation of suspended substances and the formation of il at the bottom.

Depending on climatic conditions, from the content of pollution in waste water and on the requirements for the quality of purified water, the load in aerobic-anaerobic ponds varies within 10 .. .300 kg of military-industrial complex? SUT.

In aerobic ponds with natural aeration, the saturation of water oxygen is due to atmospheric aeration and photosynthesis. Such ponds have a small depth (0.3 ... 1 m), welllighted and warm up to the solar rays, which leads to the intensive development of plankton algae and bottom higher plants. Cleaned water moves in them with very low speeds. The time of water in these ponds ranges from 7 to 60 days. If the biological ponds are an independent sewage treatment, wastewater, passing outstanding, are diluted before entering the ponds 3-5 volumes of technical water. Load on them: For seduction wastewater without dilution - up to 250 m 3 / hectares of day, for biologically purified - up to 500 m 3 / ha? SUT.

The advantages of ponds with natural aeration are simplicity of device and maintenance, minimum operating costs. However, the rates of seizure and biological oxidation of organic pollution in such ponds are low, large areas are required for cleaning.

Ponds with artificial aeration due to the intensification of biochemical processes in them take 10 ... 15 times less square, have a significantly smaller volume, and the depth

4 .. .6 m. The required degree of water purification in them is usually achieved in 1 ... 3 days. The speed of water movement in such ponds exceeds 0.1 m / s, oxidative power - 5 ... 20 g of BPK / m 3 -H, the achieved load is 1000 kg of BOD / Gasut and above. Waste water consumption can reach 10 ... 25 thousand m 3 / h. Ponds of large industrial enterprises are structures of up to 1 million m 3, equipped with a large number of aerators. For water aeration, mechanical (mixing), pneumatic (air injection) or pneumomechanical types are used. The type of aerators, their required number and the volume of the zone serviced by each of the aerators are chosen based on the conditions of maintenance of the active ral state, the amount and content of oxygen required for the oxidation of contaminants and maintain aerobic conditions, minimizing the volume of stagnant zones.

The configuration of ponds is often determined by topographic features of the terrain. Usually, the aerated ponds are earthen 2-5-section basins with a ratio of the length to a pond width of at least 20, with a dispersed feed and removal of waste water, either a sludge mixture and their subsequent upset for 2 ... 2.5 hours. With smaller relations Length to the width The location of intake and graduation devices is solved in such a way as to ensure the movement of water throughout the living cross section of the pond. In ponds with artificial aeration, the volume of congestion zones does not exceed 10%.

Compared to ponds with natural aeration in bioprudes with artificial aeration, algae are developing less actively. This reduces the volume of secondary biomass and water pollution with algae metabolism products. However, the construction and operation of artificially aerated ponds is expensive, the operational costs increase.

In Russian practice, the aerated ponds are most widely used in the pulp and paper, food and a number of other industries.

The intensity of the processes and the depth of the surface of wastewater in the aerated biological ponds can be significantly increased, recycling the active IL, separated from purified water in secondary sumps (or other structures for the altalization). In nuts mode, high-load aerobic ponds work. Ponds with recycling of il can be used as self-treatment facilities or as one of the cleaning steps. Low-loaded ponds are usually used to purge wastewater after aerodynics from MIC 25 ... 50 mg / l. In this case, they work on Ile, endowed from secondary septicles, as well as on the microflora, developing in the pond itself. To avoid the bottom of the bottom, the water velocity in such ponds should be higher than 0.007 m / s.

In contact bioprudes with artificial aeration, cleaning is carried out in two stages - aeration and deposition. During a period, wastewater is served in the pond, but not removed from it. With the termination of aeration, IL is settled and the clarified water is removed from the pond. Alternation of aeration and deposition are carried out in automatic control mode.

In contact bioprudes with natural aeration, there is a resistant waste water, if necessary, it is diluted with 3-5 volumes of clean water and produced into small non-peccant ponds. After 20 ... 30 days, the water is descended and replenished with dilute wastewater. The quality of cleaning in such non-flowing ponds is higher than in procurement.

In cascade ponds, installed usually on the ground, having a bias, undiluted waste water passes sequentially through a 4-6-step cascade of ponds with an aerobic pond on the first stage, algae, rachko, fish-water ponds. Fish breeding in such ponds is possible after passing 3-4 steps. For the breeding of fish in early spring in the pond produced 500-2000 masks per 1 hectare. Fish growth is by the end of the autumn period

500 ... 800 kg per 1 g. Fals fish produce late autumn. The presence of a large mass of nutrients in water contributes to the intensive growth of algae (ore). To combat them, it is desirable to breed in fish-water ponds of ducks, for which the rod is a good feed.

The expediency of using biological ponds is determined by the concentration of pollution and wastewater consumption, as well as specific climatic, soil and topographic conditions, the level of mineralization of water. Under the bioprussa, it is necessary to remove large land areas, so they often create them in the floodplains, in shallow water and in areas of rivers with small slopes. In such cases, with abundant development in them, air-water and immersed vegetation are actually exploited as hydrobotanic sites, or bioplato (see below).

For normal operation of bioprodov, it is necessary to observe the optimal pH values \u200b\u200band sewage temperature. Temperature must be at least 6 ° C. Since the mode of operation of biopudov depends on temperature and level of illumination, it creates certain difficulties to stabilize cleaning.

When using biopudas as independent cleaning systems, wastewater pollution should not exceed BOD P0L11 \u003d 200 mg / l for ponds with natural aeration and over 500 mg / l - for ponds with artificial aeration. When BPK is full above 500 mg / l, pre-purification of wastewater is necessary. In the ponds for the ponds, the wastewater is sent after biological or physico-chemical cleaning with BOD, full of biopruses are often used to remove excess nitrogen and phosphorus from wastewater. However, sometimes self-cleaning processes occurring in biopruds, especially in the initial period of their operation, are limited by biogenic elements, insufficient number of microorganisms involved in removing contaminants. In biopruses with a balanced ratio of carbon flow and the content of biogenic elements, the concentration of ion IN / is not more than 0.2 mg / l, no. ~

In the course of operation of biological ponds, careful control over the state of groundwater (their water, flow into the groundwater pollutants and the dynamics of their distribution) is necessary. If an artificial bioprod is used, then to reduce the filtration flow of water into the thickness of the soils, the box of the bioprud is laid with clay, other waterproof materials, or create conditions that are conducive to the formation of such a waterproof layer (for example, with the development of anaerobic microbiological processes, dragging and fluffing the bottom layer. ).

As a result of photosynthesis, primary products are formed in ponds, so the biomass increase in biological ponds often exceeds the amount of organic substances contained in the wastewater, reaching 100 ... 200 kg / hectares of day and more, the pond overlaps algae and plants, the problems of secondary pollution of water arise with residues and their metabolism products whose decomposition causes additional oxygen consumption and an undesirable increase in biogenic elements in the reservoir. More difficult compounds are lowered to the bottom and contribute to the water reservoirs. With excessive development of algae and plants, the water quality is not only deteriorated, but floating carpets from dead parts are formed on the surface of the pond, the shore is contaminated. To avoid these problems, it is necessary to periodically remove the excess biomass periodically: the surface phytomass is usually every year at the end of the growing season, and such plants like a small row, not less than once a week.

In the context of Russia, the bioprud is impossible to use in the cold season, in the fall they empty or used in winter as wastewater storage. In the spring, before commissioning, in bioprudes with natural aeration, it is plowing the bottom and, if necessary, planting vegetation. Then poured with wastewater, withstand to an almost complete disappearance of ammonium nitrogen and transfers to a duct with the calculated load. The time of ripening of ponds for the middle strip of Russia is about 1 month.

The intensive biomass growth often serves an obstacle to the use of ponds in the system of sewage treatment plants, and effective methods for removing algae have not yet been developed. At the same time, on the basis of the collected biomass of algae and plants, useful products can be obtained: feed, bio-compost, biogas, liquid hydrocarbons, paper, etc. So, with 1 hectare of algae ponds, you can get fertilizers for 10 ... 50 hectares of fields . In areas with high insolation, it is advisable to specifically grow algae or cyanobacteria in biopruses, such as cleaning the estate of livestock and bird fattening. About 40% of nitrogen of such enterprises is fixed by algae, which are then fed by animals. In biomass of cultured green algae contains 50 ... 60% protein, and in biomass blue-green - 60 .. .70%.

In Belgium, green algae Bubgosnxiop Gaisi! Asht is grown together with a rocky in shallow ponds, where the estates of the livestock complex and other contaminated waters are sent. For better development of algae, the water temperature is adjusted to 20 ... 30 ° C. Biomass is processed into biogas or produce a protein feed additive for fish and chickens, dyes, cosmetics. The rich in the mineral components of the sludge remaining after biogasification is used to intensify the cultivation of unicellular green algae BSEBESTSH BR. Thus, a biotechnology system with a partially closed cycle of substances is implemented.

Water hyacinth, microalgae of childbirth BO1GoSusis, Satubotopaz, Euipainee and some others are capable of synthesize and accumulate hydrocarbons in their cells and polyatomic alcohols. Green alga bipayep Baagbay accumulates glycerin (up to 85% of SV). The algae of iaosossiy bgipp-hydrocarbons of the composition from to 34 in an amount of up to 75% of the dry matter. Cell-filled cells b. Lgipp floes on the surface of the ponds. After collecting and drying plants and algae, hydrocarbons can be extracted by extraction by organic solvents and distillation.

3.

Biological ponds ( sewage treatment )

Biological ponds with natural and artificial (pneumatic or mechanical) aeration. Apply for cleaning and fingering of urban, industrial and surface wastewater containing organic pollutants.

At the same time, depending on the designation of the structure, the wastewater supplied to it must meet the requirements presented in Table. 13, and permissible costs in Table. fourteen.

Table 13.

The magnitude of the BOD is full of wastewater suppressed in biological ponds

Type of aeration	The magnitude of the BOD is full of wastewater supplied to bioprud, mg / l, no more
	Sewage treatment	Peppermaster
Natural aeration
Artificial aeration

Table 14.

Permissible wastewater costs summarized in biological ponds

Type of aeration	Permissible wastewater costs supplied to bioprud, m 3 / day, no more.
	Sewage treatment	Peppermaster
Natural aeration		10000
Artificial aeration	10000	Not limited

Note. If the value of the BPK is full of wastewater supplied to purification in the bioprud exceeds the values \u200b\u200bspecified in Table 13, then the preliminary cleaning of these waters should be provided.

Biopruses should be arranged on non-filtering or weakly filtering soils. With adverse fittings, anti-filtering measures should be carried out, i.e. Waterproofing structures. In relation to residential buildings, they are placed from the leeward side of the dominant direction of the wind in the warm season. The direction of water movement in them should be perpendicular to this direction of the wind.

Bottles of biological ponds are arranged using, whenever possible, natural drops of terrain. The form of ponds in the plan takes depending on the type of aeration, namely: with natural, mechanical and pneumatic aerations - rectangular; When using self-deviating aerators - round. In rectangular structures, smooth roundings of the corners are recommended to prevent congestion zones in them.

The radius of these roundings should be at least 5 m. In addition, in ponds with natural aeration in order to provide a hydraulic mode of movement of water close to the conditions of complete displacement, the ratio of the length of the structure to its width should be at least 20, and with lower values \u200b\u200bof this relationship It should include the designs of intake and graduation devices that ensure the movement of water throughout the living cross section of the pond, i.e. Distributed intakes and wastewater issues (Fig. 10). With artificial aeration, the aspect ratio of sections can be any, but the speed of water movement supported by aerators, at any point of the pond should be at least 0.05 m / s.

Note. In biological ponds with artificial wastewater aeration, the ratio of length to width in which is 1 ... 3, the hydraulic mode of fluid movement of the corresponding conditions for the perfect (complete) mixing should be taken.

Constructive biological ponds consist not less than two parallel sections with 3 ... 5 sequential steps in each (for example, Fig. 11). At the same time, it should be provided to disable any section for cleaning or preventive repair without disrupting the rest of the work. Sections and levels of biopuds are divided by enclosing dams and dams performed from soils that can save form. Their minimum width on top should be 2.5 m.

Note. In biological ponds, less than 0.5 hectares of the width of the enclosure dams and the dams at the top can be reduced to 1.0 ... 15 m.

In the presence of filtering through protective dams and platinum, it is necessary to provide for their "clothing" as an anti-filtration screen of clay (0.3 m thick) or polymer films. The slopes are taken on the basis of the characteristics of the soils (Table 15).

Table 15.

Residency of slopes of separation and fenced dams and dams

View of soil	Roughness of slopes
Wet clay and thin soils
Wet sandy and sabad soils
Dry clay and thin soils	1:1,5
Dry sandy and suesy soils

The inlet of wastewater into biological ponds, as well as overclivs of the fluid between the cleaning steps, is carried out with the help of wells equipped with devices that allow you to change the level of filling steps. Marking of the strain (intake) pipe should be higher than the bottom of the pond by 0.3 ... 0.5 m. At the same time, the water intake in the ponds with artificial pneumatic aeration is performed through the horizontal pipeline, the output of which is located on the concrete pillow, is directed up at an angle of 90 0 and is located below the estimated level of ice, and with mechanical aeration - through the pipeline directly to the zone of active mixing. In addition, at the location of the bypass pipe to avoid erosion of the slope, the corresponding participants are strengthened by stone or concrete slabs. For the production of wastewater from the structure (steps), a premium device is intended located below the water level by 0.15 ... 0.20 working depth of the pond (depth of water).

In order to provide the wave erosion of the inner slopes of dams, as well as the development of higher aquatic vegetation, they are laying down by stone, plates and coated with asphalt on rubbed stripes with a width of 1.5 m (1 m below the water level and 0.5 m above). So that the plates do not slip, the ledge is made, which serves as an emphasis for them. External Division Dimak should be sewed to slowly growing grass with low grass, capable of preventing erosion, for example, with dusty Sizem. Exceeding the construction height of the dam above the estimated water level in the pond should be less than 0.7 m.

To increase the efficiency of wastewater treatment to BOD, a full \u003d 3 mg / l, as well as a reduction in the content of biogenic elements in them (first of all, nitrogen and phosphorus) it is recommended to use higher aqueous hydrogen vegetation in the ponds (reeds, rogoz, cane, etc.). This vegetation should be placed in the last stage of the pond. Moreover, the area occupied by the highest aqueous vegetation can be determined by a load of 10,000 m 3 / day per 1 hectare with a landing density of 150 ... 200 plants per 1 m 2.