What can be cooked from squid: quick and tasty

Lyubertsy Wastewater Treatment Plant (VOC) power 3 million m3 / day, which are the largest in Europe, provide reception and cleaning of domestic and industrial Wastewater North-West, North-East and East districts of the city of Moscow, as well as cities of the forest-park zone: Khimki, Dolgoprudny, Mytishchi, Balashikha, Reutovo, Zheleznodorozhny, Lyubertsy.

Lyubertsy treatment facilities operate according to the traditional technological scheme of complete biological treatment: the first stage - mechanical treatment, including filtering water on grates, trapping mineral impurities in sand traps and settling water in primary sedimentation tanks; the second stage is biological water purification in aeration tanks and secondary sedimentation tanks. The processes taking place here are akin to the processes of self-purification in natural reservoirs - rivers and lakes, but the speed of the processes has been increased many times over thanks to specially developed technologies.

Technological scheme of wastewater treatment of the Lyubertsy treatment facilities

Complex The VOC includes 3 independently functioning wastewater treatment units: the Old Station (LOSst.) With a design capacity of 1.50 million m3 per day, the 1st block of the Novolyuberetsk Wastewater Treatment Plant (NLOS-1) - 1 million m3 per day and the second block of the Novolyuberetsk Wastewater Treatment Plant (NLOS-2) - 500 thousand m 3 per day.

A feature of the VOC is the commissioned in 2006 nutrient removal unit where deep removal of nitrogen and phosphorus takes place. In addition, facilities were commissioned in 2007 ultraviolet disinfection, with a capacity of 1 million m 3 / day of treated wastewater.

With wastewater, VOCs receive a large amount of different types waste: household items of townspeople, food production waste, plastic containers and plastic bags, as well as construction and other waste. To remove them on VOC, two types of mechanized gratings with gaps of 5 and 6 mm are used.

The second stage of mechanical wastewater treatment is sand traps - structures used to remove mineral impurities contained in the incoming water. Mineral contaminants in wastewater include: sand, clay particles, solutions of mineral salts, mineral oils.

Having passed the first two stages of mechanical treatment, the wastewater enters the primary sedimentation tanks intended for precipitation of undissolved impurities from the wastewater. Structurally, all primary sedimentation tanks on VOC are open and have a radial shape, with different diameters - 40 and 54 m.

Clarified waste water after the primary sedimentation tanks undergoes complete biological treatment in aeration tanks. Aeration tanks – open reinforced concrete structures of rectangular shape, 2, 4 corridor type. Biological wastewater treatment is carried out using activated sludge with forced air supply.

The sludge mixture from the aeration tanks enters the secondary sedimentation tanks, where the process of separating the activated sludge from the purified water takes place. Secondary sedimentation tanks are structurally similar to primary sedimentation tanks. Sediments formed at various stages of wastewater treatment are fed to a single sludge treatment complex.

Sediments formed at various stages of wastewater treatment are fed to a single sludge treatment complex, which includes

belt thickeners to reduce the moisture content of the sludge,
digesters for fermentation and stabilization of sludge in thermophilic mode (50-53 0 С),
decanter centrifuges for sludge dewatering using flocculants.

The dewatered sludge is transported by third-party organizations outside the territory of treatment facilities for the purpose of neutralization / disposal and / or use for the production of finished products.

The simplest and most common method of sludge dewatering is drying them on sludge beds with a natural base (with or without drainage), with surface outlet water and pa sealing sites.

The first are planned parcels of land (maps), surrounded on all sides by earthen ridges (Fig. 4.60). Raw sludge from sedimentation tanks or fermented from digesters, two-level sedimentation tanks or other structures, having a humidity of 90% (from two-level sedimentation tanks) to 99.5% (non-fermented activated sludge), is periodically poured in a small layer into areas and dried to a moisture content of 75-80% ...

Moisture from the sediment partially seeps into the ground, but most of it is removed by evaporation. At the same time, the volume of the sediment decreases. The dried sludge gets a moist earth structure. It can be shoved and loaded onto trolleys and dump trucks for transportation to the place of use.

Sludge pads on a natural foundation without drainage are used in cases where the soil has good filtering ability (sand, sandy loam, light loam), the level groundwater located at a depth of at least 1.5 m from the surface of the map, and seeping - / - ditch of the protective ditch, 2 - road, 3 - drainlatok; 4- Іbruski,SupportiveSludge spreading tray; 5 - sludge distribution tray, 6 - drainage well; 7 - collection drainage pipe,S- drainage layer, 9 - drainage pipes, 10 - exit to the haggard, -drainage ditch, 12 - gates, 13 - wooden board under the drain tray;K-1. K-2 ; K-3, K-4 and K-5 - wells

The remaining drainage water can be discharged into the ground for sanitary conditions. At a shallower depth of groundwater, a lowering of their level is envisaged.

If the soil is dense, poorly permeable, the sites are equipped with tubular drainage laid in ditches filled with crushed stone and gravel. The distance between the drainage ditches is recommended to be taken equal to 6-8 m, the initial ditch depth is 0.6 m with a slope of 0.003.

At small sewage treatment plants, for the sake of ease of operation, the width of individual cards is not more than 10 m.At medium and large stations, the width of the cards can be increased to 35-40 m. The dimensions of the cards should be assigned taking into account the placement of the sediment released at a time with a layer thickness in summer 0.25-0.3 m and 0.5 m in winter.

The cards are separated from each other by protective rollers, the height of which is taken 0.3 m above the working level.

The sediment is distributed over the cards using pipes or wooden trays, which are mostly laid in the body of the separation roller with a slope of 0.01-0.03 and provided with outlets.

Sludge pads must be promptly freed from dried sediment. At small sewage treatment plants, the sludge is manually loaded into machines and transported for use as fertilizer to the nearest collective and state farms.

Sometimes narrow-gauge tracks for trolleys are laid on dividing rollers, on which the sediment is transported outside the area and there is unloaded into cars.

In winter, the frozen sediment is split by special machines into separate blocks, which are then taken out to collective farm fields.

At medium and large stations, scrapers and bulldozers are used to rake sediment. The posture collected in dumps is loaded into vehicles using a peat or manure loader mounted on the basis of a DT-54 tractor, or a multi-bucket loader. The latter is the most economical of the mechanisms used - its capacity is up to 40 m3 / h.

In areas with an average annual air temperature of 3-6 ° C and an average annual precipitation of up to 500 mm, it is recommended to arrange sludge pads with sedimentation and surface drainage of sludge water for treatment facilities with a throughput of more than 10,000 m3 / day. In fig. 4.61 shows sludge ponds of this type, built at the Kuryanovskaya aeration station. Sludge platforms with surface drainage of sludge water are designed in the form of several (4-7) independently operating cascades. Each cascade consists of four to eight staggered maps. The overflow of sediment from the supply pipelines is provided on the upper cards. As it accumulates, the upper layer of sludge water (or sediment) is diverted to the underlying map through reinforced concrete bypasses-wells. The settled sludge water from the bottom card of the cascade is pumped into the primary sedimentation tanks of the treatment plant, since the content of suspended solids in it can reach 1.5-2 g / l. The volume of settled sludge water is 30-50% of the volume of the dewatered sludge, the moisture content of which is reduced from 97 to 94-95%. Further dewatering of the sludge proceeds due to the evaporation of moisture from the surface of the sludge.

The useful area of one map is taken to be 0.25-1 hectares with a width-to-length ratio of 1: 2-1: 2.5.

Sludge compaction pads were developed by the Soyuzvodok Institute - nalproekt in cooperation with the LISS department of sewerage. The platforms consist of rectangular tanks with watertight bottoms and walls. The walls are constructed from prefabricated reinforced concrete unified panels 2.4 m high, the bottom is monolithic. The working depth of the platform is 2 m.

If there is not enough space for the arrangement of open sludge platforms, then sometimes they arrange covered sludge platforms like greenhouses, overlapping them with glazed frames. Such sites have been built in Kislovodsk. According to experimental data, the annual load on them is 9-10 m3 / m2 during drying of sediments from digesters.

The area of sludge beds depends on the volume of sediment, the nature of the soil on which the site is arranged, climatic conditions, as well as on the structure of the sediment.

The load of sediment on sludge pads in areas with an average annual air temperature of 3-6 ° C inclusive and an average annual precipitation of up to 500 mm should be taken according to table. 4.36: for areas with different mean annual air temperatures, the appropriate climatic factors should be entered.

table 4.36 Load on sludge beds with natural bedding

When designing sludge beds with surface drainage of sludge water, the load is assumed to be 1 m3 / m2 per year.

Sludge seals are calculated according to the load q, which depends on the working depth of the site and the number of unloading per year, taken depending on the properties of the sediment and climatic conditions from 1 to 5.

The daily volume of the fermented sludge Wc§ discharged from the two-tier sedimentation tanks is determined taking into account the decrease in its volume due to compaction and fermentation according to the formula

^ sat = ~. (4.117)

Where Kos is the consumption of raw sludge, determined by the formula (4.101);

A is the coefficient of reducing the volume of sludge due to its decay

When fermented, equal to 2; B - the same, due to its compaction from 95 to 90% humidity, equal to 2.

Hence the useful area of sludge beds S , m2, for sludge from two-tier sedimentation tanks with an annual load of sediment K, m3 per 1 m2 of surface will be:

S = ----------. (4.118 *

The daily volume of sludge from digesters UMet without separation of sludge water does not change against the initial volume of sediment from settling tanks and is:

Therefore, when determining the area of sludge areas for sediment from digesters, the decrease in volume for compaction and fermentation is not taken into account, and the area is approximately 2-3 times larger than for sediment from two-tier ponds.

It is necessary to check the sufficiency of the area obtained in the calculation, taking into account the freezing of the sediment in winter. The duration of the period during which freezing occurs is determined by the number of days with an average daily temperature below -10 ° C. Part of the moisture (25%) is filtered and evaporated in winter. 80% of the surface of the maps of the sludge areas is allocated for freezing, and 20% is left for use during the spring thaw.

Freezing layer height / g HAm depends on climatic conditions (for middle lane USSR it is equal to 0.5-1 m):

Wtk 2

Ynam = -G7-, (4.120)

Where W is the daily volume of sediment, m3;

5 - ■ usable area of sludge platforms, m2;

T- freezing period, days; - part of the area allotted for winter freezing, usually equal to 0.75;

K2 is a factor that takes into account the reduction in sediment volume due to winter filtration and evaporation, usually equal to 0.75.

The performed calculations determine the working (useful) area of the sludge platforms. The additional area occupied by rollers, roads, grooves, etc., is taken into account by a coefficient, the values of which range from 1.2 (for large stations) to 1.4 (for small stations).

Sludge sites of treatment facilities are necessary for dewatering sewage sludge.

The base of these sites can be both with a natural base (with and without drainage), as well as with surface drainage. Sludge plots are planned plots of land (maps), which are surrounded on all sides by earthen ridges.

Sediment from sedimentation tanks or digesters, the moisture content of which is from 90 to 99.5%, is poured into the areas with a certain frequency and dried up to 75-80%. A small part of the sediment seeps into the ground, but a larger percentage of it evaporates. Sludge plots with a natural base will not drain if they are installed on soil with good filtration capacity. And for dense, poorly permeable soil, a tubular drainage is created, laid in ditches with crushed stone and gravel.

Wastewater treatment plant small size have a width of cards of 10 m, and on large ones it increases to 35-40 m. The cards are separated from each other by protective rollers, with a height of 0.3 m above the working level. The sediment is distributed over the maps using pipes. Sludge platforms are promptly cleared of sediment. In large treatment plants, sludge is removed using bulldozers and scrapers. For sewage treatment plants with a throughput of more than 10,000 m3 / day, sludge pads with sedimentation and surface drainage of sludge water are arranged. As it accumulates, the upper layer of sludge water is pumped into the primary sedimentation tanks. Subsequent dewatering of the sludge occurs due to the evaporation of moisture from the surface.

The area of sludge beds depends on the volume of sediment, the type of soil on which they will be organized, climatic conditions and the consistency of the sediment. Natural drying can be accelerated by tedding the sludge. During this process, the vegetation layer is removed and the surface crust is destroyed, which accelerates the drying of the sediment in the warm dry season and promotes deeper freezing in the winter. Natural cycle sites depend on climatic conditions, which is important when creating a project and subsequent operation of such sites.

The Poleka Group of Companies is engaged in the design, installation and subsequent maintenance of treatment facilities, including the maintenance of sludge beds. We offer our clients turnkey services and provide quality guarantees for equipment with a service life of up to 50 years. The use of modern and time-tested technologies makes it possible to create reliable and easy-to-use treatment facilities.

WASTEWATER TREATMENT FACILITIES.

Wastewater treatment plants, as the name suggests, are designed to treat wastewater. Their main purpose is to treat wastewater to a level suitable for further use. Wastewater treatment methods are varied and depend on the type of wastewater, pollutants and pollution levels.

Purification - treatment with the aim of destroying or removing harmful substances from wastewater. Removing wastewater from pollution is a rather complex process that can be compared to production. It contains raw materials (waste water) and finished products (purified water).

Wastewater treatment plants are installed on various types of wastewater.

Domestic waste water- formed as a result of human activity. The effluent comes from plumbing fixtures (sinks, sinks, toilets, etc.) of residential buildings, institutions, public buildings. Household effluents are dangerous because they are a breeding ground for pathogenic bacteria.

Industrial effluents- are formed in enterprises. The category is characterized by the possible presence of a variety of impurities, some of which significantly complicate the cleaning process. Industrial wastewater treatment plants are usually complex in design, have several stages of treatment. The composition of such structures is selected in accordance with the composition of the effluent. Industrial wastewater can be toxic, acidic, alkaline, with mechanical impurities.

Storm drains- due to the method of formation, they are also called superficial. Drains of this type Is a liquid that collects on roofs, roads, and squares during precipitation. Stormwater treatment plants usually include several stages and are able to remove impurities from the liquid different types, mainly mechanical and sorption cleaning. Storm runoff is the least hazardous and least contaminated of all.

Water purification systems are vital for human settlements. The consequences of the discharge of untreated wastewater are devastating to nature. Dirty water If it gets into the reservoir, it destroys the established ecosystem: the death of aquatic plants, microorganisms, fish, soil poisoning occurs. The damage is done to pets, and ultimately to human health.

In 2010, modern equipment was installed - filter presses. Thanks to the new aggregates, the volume of sludge treated has increased.

Is a complex of special structures designed to clean wastewater from the contaminants it contains. The purified water is either used in the future, or discharged into natural reservoirs (Great Soviet Encyclopedia).

Every locality needs effective treatment facilities. The operation of these complexes determines what kind of water will get into environment and how this will further affect the ecosystem. If liquid waste is not cleaned at all, then not only plants and animals will die, but the soil will also be poisoned, and harmful bacteria can enter the human body and cause serious consequences.

Every enterprise that has toxic liquid waste is obliged to deal with a system of treatment facilities. Thus, it will affect the state of nature, and improve the living conditions of a person. If the treatment complexes work effectively, then wastewater will become harmless when it gets into the ground and water bodies. The size of treatment facilities (hereinafter referred to as OS) and the complexity of treatment strongly depend on the pollution of wastewater and their volumes. In more detail about the stages of wastewater treatment and the types of O.S. read on.

Wastewater treatment stages

The most indicative in terms of the presence of stages of water purification are urban or local OS, designed for large settlements. It is household wastewater that is most difficult to purify, since it contains diverse pollutants.

For sewage water treatment facilities, it is characteristic that they are lined up in a certain sequence. Such a complex is called a line of treatment facilities. The scheme starts with mechanical cleaning. Here, grids and sand traps are most often used. This is the initial stage of the entire water treatment process.

These can be leftover paper, rags, cotton wool, bags and other debris. After the gratings, sand traps come into operation. They are necessary in order to retain sand, including large ones.

Mechanical stage of wastewater treatment

Initially, all water from the sewer goes to the main pumping station into a special tank. This reservoir is designed to compensate for the increased load during peak hours. And a powerful pump evenly pumps the appropriate volume of water to pass all stages of cleaning.

catch large debris over 16 mm - cans, bottles, rags, bags, food, plastic, etc. In the future, this garbage is either processed on site, or taken out to places where solid household and industrial waste is processed. Lattices are a type of transverse metal beams, the distance between which is equal to several centimeters.

In fact, they catch not only sand, but also small pebbles, glass fragments, slag, etc. The sand settles to the bottom rather quickly under the influence of gravity. Then the settled particles are raked into a depression at the bottom by a special device, from where they are pumped out by a pump. The sand is washed and disposed of.

... It removes all impurities that float to the surface of the water (fats, oils, oil products, etc.), etc. By analogy with a sand trap, they are also removed with a special scraper, only from the surface of the water.

4. Sediments- an important element of any line of sewage treatment plants. They release water from suspended solids, including helminth eggs. They can be vertical and horizontal, single-tier and two-tier. The latter are the most optimal, since in this case the water from the sewage system in the first tier is purified, and the sediment (sludge) that has formed there is discharged through a special hole into the lower tier. How does the process of releasing water from the sewage system from suspended solids occur in such structures? The mechanism is pretty simple. Sediment tanks are large-sized tanks of round or rectangular shape, where the sedimentation of substances under the influence of gravity takes place.

To speed up this process, you can use special additives - coagulants or flocculants. They promote adhesion of small particles due to a change in charge, larger substances precipitate faster. Thus, sedimentation tanks are irreplaceable structures for the purification of water from the sewerage system. It is important to take into account that they are also actively used for simple water treatment. The principle of operation is based on the fact that water enters from one end of the device, while the diameter of the pipe at the outlet becomes larger and the fluid flow slows down. All this contributes to the deposition of particles.

mechanical wastewater treatment can be used depending on the degree of water pollution and the design of a particular treatment plant. These include: membranes, filters, septic tanks, etc.

If we compare this stage with conventional water treatment for drinking purposes, then in the latter version such structures are not used, they are not needed. Instead, the processes of clarification and discoloration of water take place. Mechanical cleaning is very important, as in the future it will allow more efficient biological treatment.

Biological wastewater treatment plant

Biological treatment can be both an independent treatment plant and an important stage in a multistage system of large urban treatment complexes.

The essence of biological treatment is to remove various pollutants from water (organic matter, nitrogen, phosphorus, etc.) using special microorganisms (bacteria and protozoa). These microorganisms feed on harmful impurities in the water, thereby purifying it.

From a technical point of view, biological treatment is carried out in several stages:

- a rectangular tank, where water after mechanical cleaning is mixed with activated sludge (special microorganisms), which purifies it. Microorganisms are of 2 types:

Aerobic- using oxygen for water purification. When using these microorganisms, the water must be enriched with oxygen before entering the aerotank.
Anaerobic- DO NOT use oxygen for water purification.

It is necessary to remove unpleasant smelling air and then purify it. This workshop is necessary when the volume of wastewater is large enough and / or the treatment plant is located near settlements.

Here the water is purified from activated sludge by settling it. Microorganisms settle to the bottom, where they are transported to the pit using a bottom scraper. A surface scraper mechanism is provided to remove floating sludge.

The purification scheme also includes sludge digestion. Of the treatment facilities, a digester is important. It is a tank for fermenting sludge, which is formed during settling in two-tier primary sedimentation tanks. The digestion process produces methane that can be used in other technological operations... The resulting sludge is collected and transported to special areas for thorough drying. Sludge platforms and vacuum filters are widely used for sludge dewatering. After that, it can be disposed of or used for other needs. Fermentation occurs under the influence of active bacteria, algae, oxygen. Biofilters may also be included in the sewage water purification scheme.

It is best to place them before the secondary sedimentation tanks, so that the substances that are carried away with the water flow from the filters can settle in the sedimentation tanks. It is advisable to use the so-called pre-aerators to speed up the cleaning. These are devices that contribute to the saturation of water with oxygen to accelerate the aerobic processes of oxidation of substances and biological purification. It should be noted that water purification from the sewage system is conventionally divided into 2 stages: preliminary and final.

The treatment plant system can include biofilters instead of filtration and irrigation fields.

- these are devices where waste water is treated by passing through a filter containing active bacteria. It consists of solids, which can be used as granite chips, polyurethane foam, foam and other substances. On the surface of these particles, a biological film is formed, consisting of microorganisms. They decompose organic matter. Biofilters need to be cleaned periodically as they become dirty.

Waste water is fed into the filter in a metered dose, otherwise a high pressure can kill beneficial bacteria. After the biofilters, secondary sedimentation tanks are used. The sludge formed in them enters partly into the aeration tank, and the rest of it goes to the sludge compactors. The choice of one or another method of biological treatment and the type of treatment facilities largely depends on the required degree of wastewater treatment, relief, type of soil and economic indicators.

Wastewater post-treatment

After passing the main stages of treatment, 90-95% of all contaminants are removed from wastewater. But the remaining pollutants, as well as residual microorganisms and their waste products, do not allow this water to be discharged into natural reservoirs. In this regard, various wastewater treatment systems were introduced at the treatment facilities.

In bioreactors, the following pollutants are oxidized:

organic compounds that were too tough for microorganisms,
these microorganisms themselves,
ammonium nitrogen.

This happens by creating conditions for the development of autotrophic microorganisms, i.e. converting inorganic compounds into organic ones. For this, special plastic filling discs with a high specific surface area are used. Simply put, these are discs with a hole in the center. Intensive aeration is used to speed up the processes in the bioreactor.

Filters purify water using sand. The sand is continuously updated automatically. Filtration is carried out in several installations by supplying water to them from the bottom up. In order not to use pumps and not consume electricity, these filters are installed at a lower level than other systems. The flushing of the filters is designed in such a way that it does not require a large amount of water. Therefore, they do not occupy such a large area.

Ultraviolet water disinfection

Disinfection or disinfection of water is an important component that ensures its safety for the reservoir into which it will be discharged. Disinfection, that is, the destruction of microorganisms, is the final stage in the purification of sewage effluents. For disinfection, a wide variety of methods can be used: ultraviolet irradiation, alternating current action, ultrasound, gamma irradiation, chlorination.

UFO - very effective method, with the help of which approximately 99% of all microorganisms are destroyed, including bacteria, viruses, protozoa, helminth eggs. It is based on the ability to destroy the membrane of bacteria. But this method is not widely used. In addition, its effectiveness depends on the turbidity of the water, the content of suspended solids in it. And the UFO lamps quickly become covered with a coating of mineral and biological substances. To prevent this, special emitters of ultrasonic waves are provided.

The chlorination method is most often used after treatment facilities. Chlorination is different: double, superchlorination, with preammonization. The latter is necessary to prevent unpleasant odors. Superchlorination involves exposure to very high doses of chlorine. The double action is that the chlorination is carried out in 2 stages. This is more typical for water treatment. The method of chlorination of water from the sewage system is very effective, in addition, chlorine has an aftereffect, which other methods of purification cannot boast of. After disinfection, the effluent is discharged into the reservoir.

Phosphate removal

Phosphates are salts of phosphoric acids. They are widely used in synthetic detergents (washing powders, dishwashing detergents, etc.). Phosphates, getting into water bodies, lead to their eutrophication, i.e. turning into a swamp.

Wastewater purification from phosphates is carried out by the dosed addition of special coagulants to the water in front of biological treatment facilities and in front of sand filters.

Auxiliary rooms of treatment facilities

Aeration workshop

Is an active process of saturating water with air, in this case by passing air bubbles through the water. Aeration is used in many processes in waste water treatment plants. Air supply is carried out by one or more blowers with frequency converters. Special oxygen sensors regulate the amount of air supplied so that its content in the water is optimal.

Disposal of excess activated sludge (microorganisms)

At the biological stage of wastewater treatment, excess sludge is formed, since microorganisms in aeration tanks actively multiply. Excess sludge is dewatered and disposed of.

The dehydration process takes place in several stages:

The excess sludge is added special reagents that suspend the activity of microorganisms and contribute to their thickening
V sludge compactor sludge is compacted and partially dewatered.
On centrifuge The sludge is squeezed out and the remaining moisture is removed from it.
In-line dryers by continuous circulation warm air the sludge is finally dried. The dried sludge has a residual moisture content of 20-30%.
Then ooze packed in sealed containers and disposed of
The water removed from the sludge is sent back to the beginning of the cleaning cycle.

Air cleaning

Unfortunately, the sewage treatment plant does not smell the best. Particularly smelly is the biological wastewater treatment stage. Therefore, if the treatment plant is located near settlements or the volume of wastewater is so large that a lot of bad-smelling air is formed, you need to think about cleaning not only water, but also air.

Air purification usually takes place in 2 stages:

The initially polluted air is fed into bioreactors, where it comes into contact with a specialized microflora adapted for the disposal of organic matter contained in the air. It is these organic substances that cause the bad smell.
The air goes through a stage of disinfection with ultraviolet light to prevent the ingress of these microorganisms into the atmosphere.

Wastewater treatment plant laboratory

All water that leaves the treatment plant must be systematically monitored in the laboratory. The laboratory determines the presence of harmful impurities in the water and the compliance of their concentration with the established standards. If this or that indicator is exceeded, the workers of the treatment plant conduct a thorough examination of the corresponding cleaning stage. And in case of a malfunction, they eliminate it.

Administrative and amenity complex

The personnel serving the treatment plant can reach several dozen people. For their comfortable work, an administrative and amenity complex is being created, it includes:

Equipment repair workshops
Laboratory
Control room
Offices of administrative and managerial personnel (accounting, HR, engineering, etc.)
Head office.

Power supply O.S. performed according to the first category of reliability. Since the long shutdown of OS. due to lack of electricity can cause the OS to go out. out of service.

To prevent emergency situations power supply O.S. carried out from several independent sources. In the department of the transformer substation, it is planned to enter a power cable from the city power supply system. And also the input of an independent source electric current for example from diesel generator, in case of an accident in the city power grid.

Conclusion

Based on the foregoing, it can be concluded that the scheme of treatment facilities is very complex and includes various stages of wastewater purification from the sewage system. First of all, you need to know that this scheme applies only to domestic waste water. If there are industrial effluents, then in this case they additionally include special methods that will be aimed at reducing the concentration of hazardous chemical substances... In our case, the cleaning scheme includes the following main stages: mechanical, biological cleaning and disinfection (disinfection).

Mechanical cleaning begins with the use of grates and sand traps, in which large debris (rags, paper, cotton wool) is retained. Sand traps are needed to settle excess sand, especially coarse sand. It has great importance for subsequent steps. After the gratings and sand traps, the sewage treatment plant scheme includes the use of primary sedimentation tanks. Suspended substances settle in them under the force of gravity. To speed up this process, coagulants are often used.

After the sedimentation tanks, the filtration process begins, which is carried out mainly in biofilters. The mechanism of action of the biofilter is based on the action of bacteria that destroy organic matter.

The next stage is secondary sedimentation tanks. In them, the sludge, which was carried away with the current of the liquid, settles. After them, it is advisable to use a digester, the sediment is fermented in it and transported to the sludge pads.

The next stage is biological treatment using an aeration tank, filtration fields or irrigation fields. The final stage is disinfection.

Types of treatment facilities

A variety of structures are used for water treatment. If it is planned to carry out these works in relation to surface waters immediately before their supply to the distribution network of the city, then the following structures are used: sedimentation tanks, filters. A wider range of devices can be used for wastewater: septic tanks, aeration tanks, digestion tanks, biological ponds, irrigation fields, filtration fields, and so on. Treatment facilities are of several types, depending on their purpose. They differ not only in the volumes of purified water, but also in the presence of stages of its purification.

Urban Wastewater Treatment Plant

The data of O.S. are the largest of all, they are used in large metropolitan areas and cities. In such systems, especially effective methods of liquid purification are used, for example, chemical treatment, methane tanks, flotation units. They are intended for the treatment of municipal wastewater. These waters are a mixture of domestic and industrial wastewater. Therefore, there are a lot of pollutants in them, and they are very diverse. The waters are purified to the standards of discharge into the reservoir for fishery purposes. The standards are regulated by the order of the Ministry of Agriculture of Russia dated 13.12.2016 No. 552 "On approval of water quality standards for fishery water bodies, including standards for maximum permissible concentrations of harmful substances in the waters of fishery water bodies."

On OS data, as a rule, all stages of water purification described above are used. The most illustrative example is the Kuryanovskiy wastewater treatment plant.

Kuryanovskiye O.S. are the largest in Europe. Its capacity is 2.2 million m3 / day. They serve 60% of the wastewater in the city of Moscow. The history of these objects goes back to 1939.

Local treatment facilities

Local treatment facilities are structures and devices designed for the treatment of subscriber's wastewater before they are discharged into the municipal sewage system (the definition is given by the Decree of the Government of the Russian Federation of February 12, 1999, No. 167).

There are several classifications of local OS, for example, there are local OS. connected to the central sewerage and autonomous. Local OS can be used at the following facilities:

In small towns
In the villages
In sanatoriums and boarding houses
At car washes
On personal plots
At manufacturing plants
And at other sites.

Local OS can be very different from small units to permanent structures, which are serviced by qualified personnel on a daily basis.

Treatment facilities for a private house.

For the disposal of wastewater from a private house, several solutions are used. They all have their own advantages and disadvantages. However, the choice always rests with the owner of the house.

1. Cesspool... In truth, this is not even a sewage treatment plant, but just a temporary storage tank for effluent. When the pit is filled, a sewer truck is called, which pumps out the contents and takes them for further processing.

This archaic technology is still used today because of its cheapness and simplicity. However, it also has significant drawbacks, which, at times, negate all its advantages. Wastewater can enter the environment and groundwater, thereby contaminating it. For a sewage truck, you need to provide for a normal entrance, since you will have to call it quite often.

2. Storage... It is a container made of plastic, fiberglass, metal or concrete, where waste water is drained and stored. Then they are pumped out and disposed of by a sewer truck. The technology is similar to a cesspool, but the waters do not pollute the environment. The disadvantage of such a system is the fact that in the spring, with a large amount of water in the ground, the drive can be squeezed out to the surface of the earth.

3. Septic tank- is a large container, in which substances such as coarse dirt, organic compounds, stones and sand leave in the sediment, and elements such as various oils, fats and oil products remain on the surface of the liquid. The bacteria that live inside the septic tank extract oxygen for life from the precipitated sediment, while reducing the level of nitrogen in the wastewater. When the liquid leaves the sump, it becomes clarified. It is then purified with bacteria. However, it is important to understand that phosphorus remains in such water. For the final biological treatment, irrigation fields, filtration fields or filter wells can be used, the work of which is also based on the action of bacteria and activated sludge. It will not be possible to grow deep-rooted plants in this area.

The septic tank is very expensive and can take up a large area. It should be borne in mind that this is a structure that is designed to treat a small amount of domestic wastewater from the sewage system. However, the result is worth the investment. More clearly, the septic tank device is reflected in the figure below.

4. Station of deep biological treatment are already a more serious treatment plant in contrast to a septic tank. This device requires electricity to operate. However, the quality of water purification is up to 98%. The design is quite compact and durable (up to 50 years of operation). There is a special hatch above the ground for servicing the station.

Stormwater treatment plant

Although rainwater it is considered to be quite clean, but it collects various harmful elements from asphalt, roofs and lawns. Garbage, sand and oil products. In order to prevent all this from getting into the nearest water bodies, storm water treatment facilities are being created.

Water passes through them mechanical cleaning in several stages:

Sump. Here, under the influence of the Earth's gravity, large particles settle to the bottom - pebbles, glass fragments, metal parts, etc.
Thin layer module. Here oils and petroleum products are collected on the surface of the water, where they are collected on special hydrophobic plates.
Sorption fibrous filter. It picks up everything that the thin layer filter missed.
Coalescing module. It promotes the separation of oil particles that float to the surface, the size of which is greater than 0.2 mm.
Post-treatment carbon filter. It finally relieves water of all oil products that remain in it after passing through the previous stages of purification.

Wastewater treatment plant design

Design by O.S. determine their cost, choose the right treatment technology, ensure the reliability of the structure, bring wastewater to quality standards. Experienced specialists will help you find efficient installations and reagents, draw up a wastewater treatment scheme and commission the installation. One more important point- drawing up an estimate, which will allow you to plan and control costs, as well as make adjustments if necessary.

For the project of O.S. the following factors are strongly influenced:

Wastewater volumes. Designing structures for a private plot is one thing, but designing a wastewater treatment plant for a cottage village is another. Moreover, it should be borne in mind that the capabilities of O.S. must be greater than the current amount of wastewater.
Terrain. Wastewater treatment facilities require a special vehicle entrance. It is also necessary to provide for the power supply of the object, the discharge of purified water, the location of the sewerage system. O.S. can occupy a large area, but they should not interfere with neighboring buildings, structures, road sections and other structures.
Wastewater pollution. Storm water treatment technology is very different from the treatment of household.
Required cleaning level. If the customer wants to save on the quality of the treated water, then it is necessary to use simple technologies. However, if it is necessary to discharge water into natural reservoirs, then the quality of treatment must be appropriate.
The competence of the performer. If you order OS from inexperienced companies, then get ready for unpleasant surprises in the form of an increase in construction estimates or a septic tank that floated in the spring. This happens because people forget to include critical points in the project.
Technological features. The technologies used, the presence or absence of cleaning stages, the need to build systems serving the treatment plant - all this should be reflected in the project.
Other. It is impossible to foresee everything in advance. As the design and installation of the treatment plant progresses, various changes may be made to the draft plan that could not have been foreseen at the initial stage.

Stages of design of a treatment plant:

Preliminary work. They include the study of the object, clarification of the customer's wishes, analysis of waste water, etc.
Collection of permits. This item is usually relevant for the construction of large and complex structures. For their construction, it is necessary to obtain and agree on the relevant documentation from the supervisory authorities: MOBVU, MOSRYBVOD, Rosprirodnadzor, SES, Hydromet, etc.
Choice of technology. On the basis of paragraphs 1 and 2. there is a choice of the necessary technologies used for water purification.
Budgeting. Construction costs OS must be transparent. The customer must know exactly how much the materials cost, what is the price of the installed equipment, what is the wage fund for workers, etc. You should also take into account the costs of subsequent maintenance of the system.
Cleaning efficiency. Despite all calculations, the cleaning results may be far from desired. Therefore, already at the planning stage, O.S. it is necessary to carry out experiments and laboratory studies that will help to avoid unpleasant surprises after the completion of construction.
Development and approval of project documentation. To start the construction of treatment facilities, it is necessary to develop and agree on the following documents: a project of a sanitary protection zone, a draft of standards for permissible discharges, a project of maximum permissible emissions.

Installation of treatment facilities

After the project of O.S. was prepared and all the necessary permits were obtained, the stage of installation begins. Although the installation of a country septic tank is very different from the construction of a treatment plant in a cottage village, they still go through several stages.

First, the terrain is being prepared. A pit is being dug to install a treatment plant. The floor of the pit is covered with sand and compacted, or concreted. If the treatment plant is designed for a large amount of wastewater, then, as a rule, it is erected on the surface of the earth. In this case, the foundation is poured and a building or structure is already installed on it.

Secondly, the equipment is being installed. It is installed, connected to the sewerage and sewerage system, to the electrical network. This stage is very important because it requires the personnel to know the specifics of the operation of the equipment being configured. It is incorrect installation that most often causes equipment failure.

Thirdly, the verification and delivery of the object. After installation, the finished treatment plant is tested for the quality of water purification, as well as for the ability to work under conditions of increased stress. After checking OS. handed over to the customer or his representative, and also, if necessary, undergoes the state control procedure.

Maintenance of treatment facilities

Like any equipment, a sewage treatment plant also needs maintenance. First of all, from O.S. it is necessary to remove large debris, sand, as well as excess sludge that forms during cleaning. On large OS the number and variety of removed elements can be much larger. But in any case, you will have to delete them.

Secondly, the equipment is checked for operability. Malfunctions in any element can be fraught not only with a decrease in the quality of water purification, but also with the failure of all equipment.

Thirdly, in the event of a breakdown, the equipment must be repaired. And it's good if the equipment is under warranty. If the warranty period has expired, then the repair of OS. will have to be done at your own expense.