Before designing a wastewater treatment plant for household Wastewater or other types of wastewater, it is important to find out their volume (the amount of wastewater generated over a certain period of time), the presence of impurities (toxic, insoluble, abrasive, etc.) and other parameters.
Wastewater types
Wastewater treatment plants are installed on various types of wastewater.
- Domestic waste water- these are plums from plumbing fixtures (sinks, sinks, toilets, etc.) of residential buildings, including private houses, as well as institutions, public buildings... Household effluents are dangerous as a breeding ground for pathogenic bacteria.
- Industrial effluent 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 and have several stages of treatment. The completeness of such structures is selected in accordance with the composition of the effluent. Industrial wastewater can be toxic, acidic, alkaline, particulate and even radioactive.
- Storm drains because of the method of formation, they are also called superficial. They are also called rain or atmospheric. This type of effluent is a liquid that forms on roofs, roads, terraces, and squares during precipitation. Stormwater treatment plants usually include several stages and are able to remove impurities from the liquid different types(organic and mineral, soluble and insoluble, liquid, solid and colloidal). Storm runoff is the least hazardous and least contaminated of all.
Types of treatment facilities
In order to understand what blocks a treatment complex can consist of, you should know the main types of wastewater treatment plants.
These include:
- mechanical structures,
- biological treatment plants,
- oxygen-saturating plants enriching already purified liquid,
- adsorption filters,
- ion exchange units,
- electrochemical plants,
- equipment for physical and chemical cleaning,
- disinfection installations.
Equipment for wastewater treatment can include structures and tanks for storage and storage, as well as for the treatment of filtered sludge.
The principle of operation of the wastewater treatment complex
The complex can implement a scheme of wastewater treatment plants with surface or underground execution.
Wastewater treatment facilities are installed in cottage settlements, as well as in small settlements (150-30,000 people), at enterprises, in regional centers, etc.
If the complex is installed on the surface of the earth, it has a modular design. In order to minimize damage, reduce costs and labor costs for repairing underground structures, their hulls are made of materials, the strength of which allows them to withstand the pressure of soil and groundwater. Among other things, such materials are durable (up to 50 years of service).
To understand the principle of operation of wastewater treatment plants, consider how the individual stages of the complex function.
Mechanical cleaning
This stage includes the following types of structures:
- primary sedimentation tanks,
- sand traps,
- trash barriers, etc.
All these devices are designed to remove suspended matter, large and small insoluble impurities. The largest inclusions are retained by the grate and fall into a special removable container. The so-called sand traps have a limited capacity, therefore, with an intensity of effluent supply to treatment facilities of more than 100 cubic meters. m. per day, it is advisable to install two devices in parallel. In this case, their efficiency will be optimal, sand traps will be able to retain up to 60% of suspended matter. The retained sand with water (sand slurry) is discharged to sand pads or to a sand bunker.
Biological treatment
After removing the bulk of insoluble impurities (clarification of effluents), the liquid for further purification enters the aerotank - a complex multifunctional device with prolonged aeration. Aeration tanks will be divided into sections of aerobic and anaerobic cleaning, due to which, simultaneously with the splitting of biological (organic) impurities, phosphates and nitrates are removed from the liquid. This significantly increases the efficiency of the second stage of the treatment complex. The active biomass released from the effluent is retained in special blocks loaded polymer material... Such blocks are placed in the aeration zone.
After the aeration tank, the sludge mass passes into a secondary settling tank, where it is separated into activated sludge and treated effluents.
Post-treatment
Wastewater post-treatment is carried out using self-washing sand filters or with the help of modern membrane filters. At this stage, the amount of suspended solids present in the water is reduced to 3 mg / l.
Disinfection
Disinfection of treated effluents is carried out by treating the liquid with ultraviolet light. To improve the efficiency of this stage, biological wastewater treatment plants are equipped with additional blowing equipment.
Wastewater that has passed all stages of the treatment complex is safe for the environment and can be discharged into a reservoir.
Design of treatment systems
Industrial wastewater treatment facilities are designed taking into account the following factors:
- groundwater level,
- design, geometry, location of the supply manifold,
- completeness of the system (type and number of units, determined in advance on the basis of biochemical analysis of effluents or their predicted composition),
- location of compressor units,
- the presence of a free entrance for transport, which will carry out the removal of garbage held up by gratings, as well as for sewage equipment,
- possible placement of the outlet of the purified liquid,
- need to use additional equipment(determined by the presence of specific impurities and other individual characteristics object).
Important: Surface wastewater treatment plants should be designed only by companies or organizations that have an SRO certificate.
Installation of installations
The correctness of the installation of treatment facilities and the absence of errors at this stage largely determine the durability of the complexes and their efficiency, as well as the uninterrupted operation - one of the most important indicators.
Installation work includes the following steps:
- development of installation schemes,
- site inspection and determination of its readiness for installation,
- construction works,
- connection of installations to communications and their interconnection,
- commissioning, adjustment and adjustment of automation,
- delivery of the object.
Complete complex installation works(a list of necessary operations, the amount of work required for their implementation, the time and other parameters) are determined based on the characteristics of the object: its performance, completeness), as well as taking into account the characteristics of the installation site (type of relief, soil, location of groundwater, etc.) ...
Maintenance of treatment facilities
Timely and professional maintenance of the wastewater treatment plant ensures the efficiency of the equipment. Therefore, such work must be carried out by specialists.
The complex of works includes:
- removal of retained insoluble inclusions (large debris, sand),
- determination of the amount of formed sludge,
- oxygen content check,
- control of work on chemical and microbiological indicators,
- checking the functioning of all elements.
The most important stage in the maintenance of local treatment facilities is the control of the operation and prevention of electrical equipment. Typically this category includes blowers and transfer pumps. Installations of ultraviolet disinfecting radiation also need similar maintenance.
Construction country house is fraught with some inconvenience. One of them is the lack of a centralized sewerage system. Nobody wants to put "amenities" in the yard today. Autonomous stations became the solution to the problem. Modern sewage treatment plants are compact enough and able to cope with the task assigned to them.
Sewerage treatment facilities: principle of operation
The modern market offers a huge range of treatment facilities. But the principle of operation is similar for everyone.
Stage 1. Mechanical wastewater treatment, after which the water is almost completely devoid of suspended impurities. Methods:
- upholding;
- fat trapping;
- filtration.
Stage 2. Decomposition of the organic matter remaining in the clarified waters.
Clarified water is usually called the water that comes after mechanical cleaning. At this stage, it enters the biofilters, where the organic matter is decomposed. As a result, sludge precipitates and gases are released.
Stage 3. Additional water disinfection. It happens thanks to chemical agents.
Technically pure water is discharged into a reservoir or onto the ground.
In a large city where there is a central sewer system, the problem of effluents is bypassed by private individuals (subject to the proper approach of the city administration to this issue). In small villages, in country cottages, all problems have to be solved independently.
First, a design document is drawn up for sewage treatment plants. It is extremely difficult to do this without an engineering education. It is necessary to understand that no one will pat you on the head for environmental pollution in the case of an improperly constructed wastewater drainage system.
The next stage is the choice of a treatment plant. The defining indicators are type, performance.
Sewerage treatment facilities for the village:
1) Storage tank.
One of the simplest methods of organizing a local sewerage system. This is a plastic container for the collection and temporary storage of effluents. In the future, periodic pumping of the collected material with sewage equipment is required.
The advantages of a sewage storage tank:
- low cost;
- simplest installation.
Disadvantages:
- expensive service (you will have to pay for the services of sewers every time).
It is better to choose a storage tank when a small volume of wastewater is expected. It is good to install it in a country house used for periodic rest.
2) Septic tank.
Non-volatile plastic installation. Wastewater treatment is carried out by the method of mechanical sedimentation and with the help of anaerobic bacteria.
Septic tanks can be made independently from
- reinforced concrete;
- well rings;
- bricks.
It is important to properly seal the chambers so that wastewater does not enter the ground.
Cons of homemade septic tanks:
- a large amount of construction area;
- labor intensity of the construction process.
Installation of a finished septic tank can be done within two to three days.
The water discharged from the installation cannot be discharged directly into the reservoir. It's not clean enough yet. It is necessary to additionally equip the soil filtration system. This can only be done in light soils. Build a post-treatment system in clay soils very expensive.
A layer of sand and gravel for post-treatment of effluents in a professional environment is called a filtration field. The average service life of this field is ten years. Then you need to change the drainage layer or the location of the filtration field.
3) Aeration unit.
A device for biological wastewater treatment. Waste is not collected in any container and is not settled. Aerobic microorganisms destroy organic matter. At the exit - industrial water and sludge. A striking example aeration plant- sewage treatment plant Topas (not "Topaz"; TOP - part of the name of Yan Topol, system developer; AS - activation system).
Advantages of aeration plants:
- compact size, there is no need to equip a filtration field;
- lack of noise and smell;
- the degree of wastewater treatment is up to 98%;
- the ability to choose the capacity of the station (from installation for one house to installation for the whole village).
Disadvantages:
- high cost of the station;
- it requires electricity to work.
To select a treatment plant, you need to analyze the following parameters:
- the volume of wastewater per day (depends on the number of people living in the house and the number of plumbing fixtures; the average water consumption per person is two hundred liters);
- how often the sewer will be used (only one season, as in the country, or all year round);
- topography and geology of the site (the nature of the soil, the depth of the groundwater, the distance from open water bodies and wells, the size of the site, the level of soil freezing in winter time etc.).
Stormwater treatment plant
Stormwater drainage is designed to collect and transport melt rainwater. Regular sewage treatment plant not suitable for these purposes. Therefore, special structures were developed storm sewer... Their main task is to divert precipitation from the foundation of the house, lawns, road surfaces, beds, etc.
Storm water drainage system:
- roof gutters for collecting melt water;
- funnels and drainpipes that direct and transport water to the stormwater inlet (it is equipped with a filter that prevents large debris from entering the system);
- a system of pipes and trays through which water enters storage well or the nearest ravine.
Sand traps with waste containers are installed in various parts of the transportation system. These devices filter the stream. They will need to be cleaned periodically.
Modern sewage treatment plants are convenient installations that effectively treat wastewater. Their competent use will provide comfort to residents and preserve the ecology of the area.
Convenience is an indispensable attribute of our time. A person wants comfort, wherever he is: in a city apartment or in a house, in nature, therefore, one cannot do without a sewage treatment plant.
Decentralized sewage treatment plants are of two main types of treatment: mechanical and biological. In the first type, there is a settling of sewage and their clarified. The second is more complicated and expensive, but it guarantees the maximum degree of wastewater treatment - this is biological treatment.
If we talk about the device of an individual sewage system, then three options are possible: a septic tank, a septic tank and deep biological treatment plants.
The basis of the the simplest system sewerage is a storage tank - a sump. Here everything is arranged in an elementary way: waste water from all sources (bathroom (shower), toilet, sink) enters the container. As the sump is filled, it is pumped out using special equipment. In this case, there is no need to talk about any at least elementary purification technology.
But do not discount drives, because they also have advantages: low cost, absolute environmental friendliness, since the container is sealed, then nothing gets into the ground at all, well, the possibility of installation even on the very small area... There is only one drawback: you have to regularly call a sewer truck, but for a summer cottage or a house where no one lives permanently, this is an ideal option. It is unlikely that you will need to pump out the sewer more often than once a year.
Septic tanks
A septic tank treatment plant is a fairly popular sewerage system. Its cost can be both minimal and quite impressive. It all depends on the choice of a septic tank. If you take a single-chamber mini installation and mount it together with a filtration well, you get the most cheap scheme, which even retirees can afford.
But when arranging a treatment system, the most important thing is safety! Even domestic wastewater is an object of environmental pollution and can threaten the environmental safety of the site. In no case, for the sake of economy, you should not install a system that could harm the health of your family members.
Volume and performance
What affects the safety of use? First of all, the capacity of the septic tank should not be small. It is easy to calculate the required volume of a septic tank: according to the standards, one person spends 200 liters of water per day, respectively, he produces so much hard water. SNiP 2.04.03-85 states that the estimated volume of a septic tank should include at least three times the daily inflow of sewage, taking into account that the system serves no more than 25 people.
This means that we multiply the number of tenants by 200, and then multiply by three, add at least 15% of the obtained value (a margin for the case when they come to visit, or the whole family gathers at home and there is a great risk of a salvo discharge from all sources: soul, toilet bowl, sink) and here is the end result - the volume you need. When a family likes to wash and wash clothes often, and on weekends a hospitable house receives guests, a septic tank power reserve of 25% should be provided.
Another important indicator characterizing the efficiency of a septic tank and, accordingly, the quality of wastewater treatment is productivity. Even models that are in the same price category and have the same volume may have different performance, even if they are not much different, but, nevertheless, take this fact into account.
Number of cameras
The number of chambers in a septic tank is directly proportional to its cost: a single chamber is cheaper than a two-chamber or three-chamber. If we talk about the justification of using a multi-chamber septic tank, then everything is not so simple. Small family with minimal water consumption, having an area with sandy soil, it is enough single chamber septic tank... When the family is large, a lot of water is consumed, the soil on the site is not very permeable, then it is better to opt for at least a two-chamber installation.
By the way, even a three-chamber septic tank cleans wastewater by a maximum of 70%, and basically, the degree of wastewater treatment by a septic tank is 50-60%. The principle of operation of such treatment facilities is that when sewage flows into a septic tank, if it has several chambers, then into the first chamber, they stratify and settle.
A sediment falls to the bottom, and a liquid with a small amount of impurities remains on top, it pours into the second chamber, where most of the already light particles settle to the bottom (the same happens in the third chamber, if any), and the clarified liquid is discharged to the ground through filtration fields, infiltrators or drainage wells. In all chambers, the process of fermentation and decomposition of organic sediment takes place.
Filtering required
Filtration is required for additional treatment of effluent leaving the septic tank. It takes place either on filtration fields, which are arranged in the ground using perforated pipes, or in drainage well... The most modern technology is the use in the sewage system additional element- infiltrator.
Industrial designs are made of plastic, they have the shape of an inverted trough. The use of this device allows even a salvo discharge into the sewer without the risk of contamination environment drains.
Infiltrator
The infiltrator is not expensive, and experts recommend using it for treatment facilities instead of filtration fields that require a significant area. But when choosing a product, pay attention to its design: it is better if it has perforated walls, then you can count on maximum performance.
The infiltrator protects the upper layers of the soil from the ingress of incompletely treated wastewater into them. Before installing it, a layer of fine-grained crushed stone is poured into the pit (give preference to granite - or from other hard rocks, and not made from construction or metallurgical waste).
The crushed stone will work as a filter, trapping organic impurities remaining in them from the incoming wastewater. And if the device is not only put on a crushed stone pillow, but also covered with crushed stone on the sides, then the filtration area will increase significantly.
Do you need an agrotechnical fabric?
One more important point: usage nonwoven fabric when installing a sewage treatment plant. Many so-called "specialists" lay it in a layer of rubble under the infiltrator. This is completely unacceptable! No functional load this material does not carry in this place, in addition, its presence will contribute to the gradual silting of the filtration layer.
In other words, the fabric will significantly impair throughput drainage layer, and over time the filtration process will become impossible. The only and very important purpose of agrotextile is filtration of sand, which, during rains, can fall into the lower layers of the soil and settle in rubble, impairing its throughput. Therefore, the tissue should be placed over the installed infiltrator.
Septic tank with biofilter
Now there are septic tanks that can work without additional wastewater treatment, in any case, the manufacturers declare this, but in practice, a device is still required drainage ditch, it is into it that the processed liquid will be diverted. These are septic tanks with biofilters.
A septic tank with a built-in biofilter, as a rule, has three chambers (but always horizontal). The first chamber is a receiver of waste streams, here the first sediment falls out, in the second chamber they settle again, and the already clarified liquid gets into the third compartment. The third chamber is the largest biofilter, since it contains the filter material.
Most often it is expanded clay, but granular polymers are also used, bulk plastic mesh or brushes. They are needed so that microorganisms can settle on them, which will process organic residues from wastewater. A biofilter is a miniature filtration field. The regulatory framework for the use of biofilters is set out in SNiP 2.04.03-85 (Facilities for biological wastewater treatment).
Advantages and disadvantages
Biofilters are either built-in to a septic tank or stand-alone. By the principle of work: aerobic and anaerobic. In some, cleaning is carried out with the help of microorganisms formed when air is available (a ventilation system is required), while in others there is no air access (sealed installations), so anaerobic bacteria settle there.
Benefits of biofilters:
- compactness;
- non-volatility;
- ease of installation and operation;
- purification of effluents up to 90-95% (when using a filter of the required performance).
But some disadvantages are inherent in these treatment plants:
- high price;
- do not pour cleaning and detergents chlorine-based, any paints, solvents, medicines ...;
- you need to regularly add concentrated preparations with strains of different bacteria;
- biofilters are not used in homes with seasonal accommodation- in wastewater, the biological process must go on constantly, and if there is no wastewater and the microflora has nothing to process, it dies.
The recommendations in each case may be different. Knowing certain nuances of the biofilter operation, consult with specialists about the validity of its use with your treatment plant.
Deep cleaning stations
And the last treatment facilities are deep biological treatment plants. So far, these are the most modern installations. In them, all processes are more intensive and the quality of cleaning is higher - up to 98%. Waste water from the system can be discharged directly into the ground or into a ditch - it will not cause any harm to the environment. Despite their efficiency, the stations themselves are modest in size and can be installed on any soil and even with high level occurrence of groundwater.
A high degree of wastewater treatment in these systems is achieved thanks to the phased aerobic and anaerobic methods. The compact housing contains: four chambers (reception, aeration tank, secondary clarifier and activated sludge stabilization section), a compressor and automatic system management.
Principle of operation
In the receiving compartment, wastewater stratification occurs: heavy fractions precipitate, and the primary treatment process begins.
Then, with the help of a pump, the liquid is pumped into the second chamber (aerotank), where the compressor injects air to activate the activity of microorganisms, so that the process of decomposition of organic compounds goes much faster. Lighter particles that float up in the wastewater are poured back into the first chamber.
After the aeration tank, purified water mixed with activated sludge enters the secondary settling tank, where the sludge settles and returns to the second chamber, from where it is pumped out to the sludge stabilization section, and clean water is discharged outside the unit. The accumulated sludge is also periodically pumped out, and this can be done using the pump supplied with the kit. Silt is an excellent fertilizer, and it can be used to feed plants in the garden, because it does not have unpleasant odor.
The advantages of this system are many. Among them, of course, high quality wastewater treatment, compactness and durability of the installation, which works completely autonomously without human intervention, but needs periodic maintenance... But the limiting factors for the use of this system are: high price and volatility.
Make the right choice!
Treatment facilities of any version have the right to exist in each specific case. To do right choice, you need to compare a lot of factors, and since even the simplest sewer system will cost a couple of tens of thousands of rubles, and more advanced and productive ones will cost much more, a mistake in choosing will cost a very tidy sum.
With all your questions and doubts, contact highly qualified specialists who will recommend you a wastewater treatment system, and subsequently install it. The employees of our company LLC "Moskomplekt" have extensive experience in the installation of various complexity of treatment facilities, and we are ready to advise you on this complex topic... Call, leave applications for installation! We work quickly, efficiently and not expensive, but with a guarantee!
Local sewage treatment plants (VOCs) are of several types, depending on the applied principle of domestic wastewater treatment. Each cleaning method has its own advantages and disadvantages, but it always finds application in a given situation. Local sewage treatment plants operate in an integrated manner, that is, cleaning takes place in several stages, and the final is to obtain clean industrial water suitable for domestic needs (except for washing and cooking).
Wastewater treatment plant
You can dispose of harmful impurities from sewage in different ways:
- Mechanical cleaning.
- Biological treatment and filters.
- Physical and chemical wastewater treatment.
- Disinfection of sewage wastewater.
Mechanical cleaning
The first and roughest cleaning option is local sewage treatment plants, in which mechanical filters are installed as the first barrier. Filtration prepares wastewater for biological treatment. Here, large solid fractions are retained during the passage of wastewater through sedimentation tanks, septic tanks, sand traps, metal mesh filters, membranes and grids that retain insoluble fractions. The whole principle of operation of sewage treatment plants for mechanical wastewater treatment consists of several successive steps:
- Grids, meshes and a metal sieve retain large debris and fractions of organic and mineral origin.
- Grit traps prevent small particles from going further through the cleaning cycle.
- The membrane removes the remaining fines - this is called deep cleaning.
- In the sump, the water is purified from the rest of the suspended particles.
After these four stages of purification, the water can be purified by 60-70%. After several years of VOC operation, a partial reconstruction of sewage treatment facilities with replacement of filters is required.
Biological wastewater treatment
If further purification is required, a biological method is used. Anaerobic microorganisms and bacteria that feed on residues are colonized in tanks with mechanically treated wastewater organic matter... At this stage of purification, activated sludge, biological filters, or anaerobic fermentation process can be started.
The physicochemical stage involves the use of various chemical substances and impurities to improve the quality of treated water. These are such complex processes as ozonation, chlorination and other chemical reactions. Therefore, the construction of sewage treatment plants should be carried out only by professionals and according to a previously developed project.
If the treatment system provides for the discharge of effluents into an artificial (natural) reservoir, then it is necessary to disinfect the water. This is done with UV filters or chlorine treatment for 30 minutes.
Cleaning with septic tanks
But such sewage treatment methods are effective for the city. And what to do for summer residents or owners country cottages and houses? The most relevant sewage treatment plants for the village or country house- these are septic tanks. And if there is demand, then there will be supply. Industry and private enterprises offer a lot different options such autonomous installations, working in different ways. Therefore, the problem of sewage disposal and treatment for detached buildings is solved by autonomous sewage treatment plants.
A septic tank is a large-capacity tank that is installed in an area at a certain depth. It is recommended to select the most efficient installation for each terrain, therefore preliminary design of sewage treatment facilities is an integral part of VOC construction. Wastewater is purified by precipitation of solid fractions. Additionally and finally, the water is purified in the filtration field. After that, it can be poured into the ground or used for technical purposes.
If you install additional filters, you can pump out water once every 4-5 years - the frequency depends on the volume of the septic tank chambers. Aerotanks are used as a post-treatment system.
An aeration tank is a device for biological wastewater treatment. It is a system of reservoirs inhabited by microorganisms. After such treatment, the water is suitable for dumping into the ground.
Correct operation of sewage treatment plants can improve the quality up to 98%. The disadvantage of this method is the mandatory presence of electricity or a good natural supply and exhaust ventilation so that bacteria do not die without oxygen and that the set volumes of effluents cannot be exceeded, otherwise the bacteria will not cope with cleaning. A tandem of biofilters and a septic tank greatly improves water quality.
UV disinfection helps protect the water from infection by viruses and pathogens. The ultraviolet installation is used in a complex, as part of other treatment facilities, since its function is not to purify water, but only to disinfect it. The UV unit disinfects water by 99%, but the disadvantage of using it is the same - the availability of electricity, which increases the already rather big cost of the station.
And how do sewage treatment plants using biological wastewater treatment work? Biological sewage treatment is the most effective method... Biological wastewater treatment plants can be installed next to residential buildings and in any climatic zones... The service life of such a system is 30-50 years.
The disadvantage of such cleaning is the presence of an unpleasant odor arising from the fermentation of waste. Modern technologies allow you to eliminate this disadvantage, but such devices are expensive.
Biological wastewater treatment is also used in conventional septic tanks - bacteria of a certain type are colonized in the septic tank chamber. But there are also storm sewer treatment plants, which are designed to collect, deliver to the septic tank and purify rain and melt water and further delivery to the filtration fields. Standard septic tanks and wastewater treatment plants may not be able to handle the large amount of rainwater, and storm sewers have been developed for this purpose.
Stormwater treatment plant
The main task of the "storm drain" is to protect the foundation of the house, road surface, lawns, etc. from flooding by rain and melt waters. What are local storm sewer treatment facilities? This is a system of downpipes, storm inlets, gutters and drainage through which water is collected and enters the collector. The collector must be below the level of soil freezing.
All elements of the storm sewer are equipped with sand traps. Standard urban sewage treatment plants are much more complex and form whole underground utilities.
The storm water inlet has an additional filter for melting and rainwater purification. After passing through the filter, the purified water enters the nearest reservoir. You can also water the garden or flower beds with it. The stormwater drain also requires routine cleaning. When choosing one or another storm sewer, take into account the following:
- Type of instalation. Many sewage systems operate in an autonomous mode, some require an electricity connection, and there are also rainwater treatment plants that cannot be operated if groundwater approach the surface very close.
- Cleaning method. The use of several cleaning methods increases the efficiency of the work.
- Place of installation. It is necessary to adhere to SNiP in this matter.
- Self or professional editing systems.
PURPOSE, TYPES OF TREATMENT FACILITIES AND CLEANING METHODS
A person in the process of his life, for his various needs, uses water. When used directly, it becomes dirty, its composition changes and physical properties... For the sanitary well-being of people, these effluents are diverted from settlements. In order not to pollute the environment, they are processed in special complexes.
Fig. 7 Treatment facilities of JSC "Tatspirtprom" Usadskiy distillery Republic of Tatarstan 1500 m3 / day
Cleaning steps:
- mechanical;
- biological;
- deep;
- UV disinfection of effluents and further release into the reservoir, dehydration and disposal of sludge.
Production of beer, juices, kvass, various drinks
Cleaning steps:
- mechanical;
- physical and chemical;
- biological and further release to the municipal collector;
- collection, dehydration and disposal of sludge.
Also read the articles on this topic.
STORAGE WASTE TREATMENT FACILITIES
VOC is a combined tank, or several separate tanks for the treatment of storm and melt water. The qualitative composition of storm water is mainly oil products and suspended solids from industrial production and residential areas. They, according to the law, must be cleared before VAT.
The device of storm water treatment facilities is being modernized every year, due to the increase in the number of cars, shopping centers, industrial sites.
Standard set equipment of storm water treatment facilities is a chain of a distribution well, a sand separator, a gas oil separator, a sorption filter and a sampling well.
Many companies are currently using combined system waste water treatment. Single-hull VOC is a container, divided internally by partitions into sections of a sand trap, an oil-oil trap and a sorption filter. In this case, the chain looks as follows: a distribution well, a combined sand and oil separator and a sampling well. The difference is in the occupied area of the equipment, in the number of containers and, accordingly, in the price. Stand-alone modules look bulky and are more expensive than single-body modules.
The principle of operation is as follows:
After precipitation or snow melt, water containing suspended matter, oil products and other contaminants from industrial sites or residential (residential) territory enters the grates of rain wells and then collects through the collectors in an averaging tank if VOCs are of accumulative type, or immediately in turn of a distribution well are supplied to the storm sewer treatment plant.
The distribution well serves to direct the very first dirty wastewater for cleaning, and after a while, when there will be no pollution on the surface, the conditionally clean wastewater through the bypass line will be discharged to the sewer or to a reservoir. Storm runoff goes through the first stage of cleaning in a sand catcher, in which gravitational sedimentation of insoluble substances and partial floatation of free-floating oil products take place. Then, through the partition, they flow into the oil-oil separator, in which thin-layer modules are installed, due to which suspended solids settle to the bottom along the inclined surface, and most of the oil particles rise to the top. The last stage of cleaning is a sorption filter with activated carbon. Due to sorption absorption, the rest of the oil particles and small mechanical impurities are captured.
This chain allows you to provide a high degree of purification and discharge the treated water into the reservoir.
For example, for oil products up to 0.05 mg / l, and for suspended solids up to 3 mg / l. These indicators are fully consistent with the current regulations governing the discharge of treated water into fishery reservoirs.
VILLAGE TREATMENT FACILITIES
Currently, near megacities are being built a large number of autonomous villages that allow you to live in comfortable conditions "in nature", without interrupting the usual city life. Such settlements, as a rule, have separate system water supply and sewerage, since there is no way to connect to the central sewerage system. The compactness and mobility of such treatment plants allows you to avoid huge installation and construction costs.
However, despite their small size, the modules contain everything necessary equipment for complete biological treatment and disinfection of wastewater with the achievement of quality indicators of treated wastewater that meet the requirements of SanPiN 2.1.5.980-00. The undoubted advantage is the complete factory readiness of block containers, ease of installation and further operation.
TREATMENT FACILITIES FOR THE CITY
Big City- large treatment facilities (OS). It is logical, because the consumption of wastewater entering for treatment directly depends on the number of inhabitants: the rate of water disposal is equal to the rate of water consumption. And for a large volume of liquid, appropriate containers and reservoirs are needed. This fact generates interest in the design and operation of such OS.
When designing sewer networks settlement the load on the pipelines is taken into account, which are selected based on the passage of the required amount of drain. In order not to bury the pipes very large diameter, through which the contaminated liquid would be transported to the vast areas of treatment facilities, in large cities several wastewater treatment plants are being built.
Thus, the megalopolis is divided into several "cities" (districts), and for each of them a cleaning station is designed.
An illustrative example are the treatment facilities in the capital of Russia, among which there are Lyuberetskie with a capacity of 3 million m 3 / day - the largest in Europe. The main unit - the old modernized OS, providing half of the plant's capacity, the other two units - 1 million m 3 / day and 500 thousand. m 3 / day.
The peculiarities of the device of such wastewater treatment plants are the increased size of the structures in comparison with the wastewater treatment plants of other cities: settling tanks with a diameter of 54 meters, and the canals are comparable to small rivers.
From the point of view of technology, everything is standard: mechanical cleaning, sedimentation, biological treatment, secondary sedimentation, disinfection. You can read on our website.
The main feature is only in what kind of structures they have for these stages of processing. For example, Moscow, as you know, was not built immediately, but it has always been a great source for treatment facilities. Reinforced concrete structures were built, which today have undergone several reconstructions and modernizations. Due to a decrease in the amount of diluted pure water some of the previously built structures are mothballed or used for other purposes. This is also the peculiarity of the OS device: the old channels of the sand traps become an intermediate reservoir, the aeration tank corridor is transformed and works a little differently.
The main thing that significantly distinguishes the OS of large cities from their smaller brothers is closed structures.
In other words, a roof is mounted on all structures built in the 60s and 70s. This is done in order to eliminate the odor that can spread to new buildings, which, in turn, have arisen due to the geographic expansion of the metropolis. And if earlier the wastewater treatment plant was significantly removed from the city, now it is located near new residential complexes.
For the same reason, sprinklers are installed on such OSs, which release special substances that neutralize the odors of effluents.
Any treatment plant is a complex interconnection of processes. Of course, they will cope with their task 100%, but there is no need to complicate their work. Waste - in the trash, plumbing - as intended.