Types of sewerage for a country house - which is better. Domestic sewage system

Not only wastewater from industrial enterprises, but even household sewage from ordinary country house. Wastewater from even such a small facility can seriously harm the surrounding environment if it is not properly treated before being discharged into open water bodies or soil. Not so long ago, to collect sewage from a private house or cottage, they built cesspools. But in Lately they are practically not used due to inconsistency sanitary standards. Now wastewater is collected in special facilities, where, after careful processing, it is 95-99% purified and can be freely discharged into water bodies or soil. In our article we will look at how domestic wastewater is treated.

To begin with, it is worth understanding the composition and characteristics of domestic sewage wastewater. This is the name of the water that was used in households. needs or in production. In addition, wastewater includes atmospheric waters that are collected from the surface of the earth.

For correct selection household cleaning technologies and industrial wastewater, you need to know the nature of the pollution. Thus, there are three types of wastewater pollution:

1. Mineral contaminants. This includes all inorganic impurities, for example, soil particles, salts of various origins, as well as various inorganic chemical elements and connections. Such pollutants can be present both in domestic wastewater and in wastewater received from industrial enterprises.
2. Organic pollutants are present in large quantities in households. drains. This includes complex elements animal and plant origin. Also included in this group of pollutants are various chemical and polymeric organic compounds. As for household sewage wastewater, 80-90 percent of it consists of impurities of organic origin. As part of the household In wastewater, such pollutants are present in the form of fecal matter, food debris, and peelings from vegetables and fruits.
3. Biological pollutants- these are various microorganisms that live in wastewater and feed on the elements contained in the wastewater. So, bacteria, fungi, viruses live in large quantities in sewage, there are helminth eggs and other protozoa.

Important to know: the concentration of biological pollutants depends on their presence in the environment, as well as on the composition of the wastewater. So, in unfavorable conditions industrial wastewater, the concentration of microorganisms may be minimal, but in households. wastewater contains the necessary nutrient medium, so there can be many times more biological pollutants.

Cleaning Standards

Wastewater treatment facilities must provide the required degree of purification. The strictest standards exist only for wastewater generated from industrial enterprises. At the same time, the standards stipulate the permissible concentration of each specific substance in purified water.

For domestic sewage, such strict requirements are not imposed. However, the rules still prohibit dumping household items. wastewater without treatment into open water bodies or soil. Homeowners may be held liable for this.

For household wastewater, the concentration of certain substances is legally regulated only if they are discharged into a reservoir. The same applies to wastewater discharged onto the terrain after treatment, because in this case, sooner or later it will still end up in the reservoir.

Such strict requirements are not imposed on wastewater discharged into the ground after a treatment plant, since in this case the owner of the house is himself interested in thoroughly purifying the liquid. Otherwise, he risks deteriorating the condition of his plot to such an extent that it will become impossible to live in the house.

Methods for treating household wastewater

Modern technologies for household cleaning. wastewater is so effective that the water after the treatment plant can be reused, that is, to water the garden with it or take it for technical needs. Thus, the following cleaning technologies are used:

• Mechanical cleaning– settling and filtration.
• Biological purification– processing of organic components of sewage wastewater by bacteria.
• Physico-chemical methods– adsorption, coagulation, flocculation, etc., as well as chemical treatment methods, which are carried out by introducing various chemical compounds into wastewater.

Important: for the treatment of household wastewater, mechanical and biological methods cleansing. The technology of the purification process depends on the selected treatment facility.

Mechanical methods

When using any cleaning technology on initial stage usually used mechanical methods. the main task this stage– separate coarse waste components from the liquid. This is usually done through the use of filters rough cleaning or in settling tanks due to the settling of heavy components to the bottom under the influence of gravity.

Important: mechanical treatment allows you to remove about 60-70 percent of pollutants from household wastewater. Sedimentation tanks are also used to treat sewage wastewater generated from industrial plants.

Since during the settling process it is possible to get rid of most of the petroleum products contained in industrial wastewater, this technique is actively used in car washes and oil refineries.

Mechanical cleaning technology is the simplest and most affordable. To implement it, one of three methods is used:

• settling;
• straining;
• filtration.

Mechanical cleaning methods are used in storm sewer structures. This method is especially effective here, since atmospheric water collected from the surface of the earth contains soil particles, branches, leaves and other large pollutants, which are perfectly retained by special sand traps. These are special structures that prevent waste from entering the sewer system.

Biological techniques

For wastewater treatment in buildings autonomous sewerage, as well as for domestic sewage from populated areas, biological treatment methods must be used. This technology is based on the use of aerobic and anaerobic organisms, for which domestic wastewater is an excellent habitat.

This technique is based on the principles of self-purification of the environment in natural conditions, because these bacteria are constantly present in the soil. These microorganisms process complex organic components of wastewater, decomposing them into gas and water. Moreover, aerobic organisms require oxygen for their vital functions, therefore, for more effective cleaning, it is necessary to create suitable conditions by installing an aeration system.

In contrast, anaerobic bacteria do not require access to oxygen, so they can live in sealed containers. However, they emit gas (methane), so facilities where purification using these organisms takes place must be equipped with a ventilation system.

Several types of VOCs are currently used biological treatment:

1. Septic tanks are sealed containers into which wastewater flows after mechanical cleaning. Septic tanks contain anaerobic bacteria that process sludge and help purify the water. However, water after a septic tank needs additional treatment, for example, filtration well, before discharging it into a reservoir or ground.
2. Septic tanks with biofilters. The principle of operation of the biofilter is based on the penetration of liquid through a layer of special coarse-grained material (crushed stone or sand), covered with a film of special bacteria. This operating principle is used in the filtration pit and filtration fields. When sewage flows through a biofilter, bacteria activate the processes of oxidation and processing of organic components.
3. Bioponds are shallow (up to 1 m) artificial reservoirs, in which the wastewater passed mechanical cleaning, are processed through anaerobic-aerobic processes. For the efficiency of the processes, it is important that the ponds are heated by the sun, therefore winter time Such reservoirs are ineffective and almost never used. Aerobic processes in a biopond can be maintained due to the supply of oxygen from the air or artificial aeration.
4. Aerotanks and digesters– these are sealed structures for biological treatment of sewage wastewater. Depending on the bacteria used, the design may use forced aeration (aeration tanks). Here, to speed up wastewater treatment processes, activated sludge is used, which contains the necessary bacteria.

Important: any biological treatment methods are used only after mechanical wastewater treatment, that is, settling.

Chemical and physical-chemical methods

For the processing and disinfection of household sewage waste, chemical and physical-chemical methods are practically not used. They are used only in the construction of structures for the treatment of industrial wastewater.

This purification technology includes the following methods:

• Coagulation allows you to increase the rate of sediment formation due to adhesion fine particles into larger elements, which, under the influence of gravity, will precipitate faster. Iron salts, lime and aluminum are usually used as coagulants. Flocculants can also be used together with coagulants.
• The adsorption technique works especially effectively. With its help it is possible to separate a large number of harmful components contained in industrial wastewater.
• The reagent-free method of wastewater treatment involves the use of heat treatment, freezing and thawing, electrocoagulation and radiation irradiation to purify wastewater.

Chemical treatment methods involve the disinfection of pre-treated wastewater by treating it with potassium permanganate, chlorine or other substances that can neutralize pathogenic organisms.

Sewerage is one of the complexes of the entire water supply and sanitation system. The main purpose of sewerage systems is the removal of industrial and domestic wastewater, human waste products and rainwater, for their further purification from impurities and contaminants and their direction for subsequent operation or discharge into water bodies or onto the ground. Sewerage is necessary element modern industrial production, agriculture and urban farming.

Disruption sewer systems for the disinfection and purification of wastewater of various origins may lead to a deterioration in the sanitary and epidemiological condition of the area. Which can lead to fatal consequences, which has happened many times in the past.

Sewerage - historical background

It is generally accepted that the ancient Romans created and developed sewers. However, the most ancient traces of the use of systems for draining polluted and used water were found in India, in Mohenj-Daro. The age of the city, and therefore the wastewater treatment systems, dates back to 2600 BC. Remains of ancient sewer structures have also been found in China.

Unfortunately, with the fall of ancient civilizations, the culture of using sewer systems lost its importance. Europe plunged into literally, into masses of sewage. Wastewater treatment systems and facilities began to be revived only in the late eighteenth and early nineteenth centuries. And at the beginning of the twentieth century, pollution was systematized and identified

Sewer classification

Sewage systems (facilities for wastewater disposal) are divided into three main groups:

• Internal sewerage is a complex of systems and equipment for collecting wastewater inside buildings and structures. Redirect to central systems sewerage. Elements internal sewerage are:

a) water intake devices - washbasins, sinks, etc.;

b) pipeline system - vertical and horizontal pipelines, plugs, collectors, discharge systems into external sewers;

V) additional elements are - local treatment facilities, pumping station, etc.;

• External sewerage– is an extensive system for collecting wastewater from structures, structures, and buildings. Delivery of wastewater to central collectors or to treatment facilities. Elements of external sewerage are: pipelines, sewer hatches, pumping stations, septic tanks, etc.
• Treatment system and facilities – the treatment facilities themselves, drainage systems,

  Organization of external sewerage

  The external sewerage network is mainly gravity-fed. It is laid with a slight slope along the flow of wastewater. Used if necessary pumping stations.

  The organization of external sewage systems is as follows:

  All-alloy – characterized by the acceptance of all wastewater;

  Separate - equipped with separate collector systems for separate collection of storm water and household wastewater;

  The modern world is unthinkable without the use of sewerage systems for the disposal and disinfection of wastewater, both storm and domestic. The use and development of sewerage and wastewater treatment systems allows us to take care of the world around us and maintain the sanitary condition of modern settlements.

Household sewage system K1 is designed for draining wastewater from toilets, bathtubs, kitchens, showers, public restrooms, garbage disposals, etc. This is the main sewer system for buildings. Its old name is “domestic-fecal” sewerage.

K1 elements

Elements domestic sewerage Let's look at K1 as an example two-story building with a basement (Fig. 13).

Here are the main elements of K1 along the flow of wastewater:

1  sanitary fixture;

2  siphon (hydraulic seal);

3  floor outlet pipeline;

4  sewer riser;

5  drainage network in the basement;

6  sewerage outlet.

Let's note some details. An elbow is shown below the siphon. It is used on low risers (no more than 1 floor). The outlet pipeline 3 is laid with a slope and connected using a straight tee to the riser 4. Audits are installed on the riser.

The top of the riser is brought above the roof into the atmosphere to a height z this is the ventilation of the sewer riser. It is necessary to ventilate the inside of the sewer, as well as to prevent the appearance of excess pressure or, conversely, vacuum in the sewer. A vacuum may appear if the riser ventilation is faulty when draining water from top floor, which will lead to the breakdown of the siphon, that is, the water from the siphon on the lower floor will leave and an odor will appear in the room.

The height of the riser above the roof is taken according to SNiP 2.04.01-85 to be no less than the following values:

z= 0.3 m  for flat unused roofs;

z= 0.5 m  for pitched roofs;

z= 3 m  for exploited roofs.

Sewer riser can be installed without ventilation, that is, not installed above the roof, if its height H st does not exceed 90 internal diameters of the riser pipe.

Recently, they have gone on sale vacuum valves for sewer risers, the installation of which at the level of the upper floor eliminates the need for a ventilation outlet for the riser above the roof of the building.

There are two outlets installed at the base of the riser, since the riser is the outermost one on the network in the basement. If the riser falls on the network pipe from above, then an oblique tee and a bend are used. It is impossible to use a straight tee in the basement, as the hydraulics of the drain deteriorate and blockages occur.

At the end of the outlet network 5 before outer wall Cleaning is assembled from a straight tee with a plug. Counting from this cleaning, the length of the sewer outlet L should not be more than 12 meters with a pipe diameter of  100 mm, according to SNiP 2.04.01-85. On the other hand, the distance from the inspection well of the yard sewage system to the wall of the building should not be less than 3 meters. Therefore, the distance from the house to the well is usually 3-5 meters.

The depth of the sewer outlet from the ground surface to the tray (bottom of the pipe) outer wall is taken to be equal to the freezing depth in a given area, reduced by 0.3 meters (the influence of the building on the non-freezing of the soil next to the house is taken into account).

The main purpose of domestic sewerage is to remove wastewater from the premises into special tanks that store and process household waste and human waste. There are several types of domestic sewerage:

• Cesspool or drain hole . This type of sewage system has been used since ancient times, and is still in use today. This type of domestic sewage system is used mainly in houses with seasonal occupancy. The main advantages of this type are its low cost and ease of installation. The main disadvantage of a cesspool is the foul odor, which is especially noticeable when removing waste from the pit.

• Filter wells. For this type of sewerage, reinforced concrete rings are used, which are installed on a layer of gravel or crushed stone one on top of the other at a level of approximately 1 m. The same material is used to fill the well with outside. The bottom of the well is made leaky so that it gradually empties. This type of sanitary sewer is suitable for sandy soils that allow wastewater to pass through. However, installing a filter well is quite labor-intensive, and its use leads to contamination of the lower layers of soil on the site.

• . It is an excellent option for autonomous sewerage on the site, but requires quite a bit financial costs. That's why this type Domestic sewerage is used to service several houses or even the entire village.

• . A very common option for an autonomous sewer system for a private home nowadays. This type of domestic sewage system has gained such popularity due to its ease of maintenance, quite pump out the septic tank once a year, and easy to install. With a certain set of skills, this type of sewer can be installed independently. In addition, the service life of such an autonomous sewer system is about 50 years, provided correct installation septic tank The main disadvantages of such household sewerage are big square for installation and significant maintenance costs.

Modern methods make it possible to achieve wastewater purification by 95-98%, which allows preserving the soil and environment in safety. The main methods of wastewater treatment are the following:

1. . It is a tank divided into 3 sections. In the first part, the wastewater settles and is naturally separated into heavy substances that settle at the bottom of the section, light oils and other substances float to the surface, while water remains in the middle. Next, the liquid flows into the second section, where it is exposed to anaerobic bacteria. At this stage, the wastewater is purified by 60-70%. Depending on the design, the liquid goes into a filter well or into a third section, where it undergoes aerobic cleaning.
2. Aerotank. The operating principle of aeration tanks is approximately the same as that of septic tanks. In the first compartment, the water is divided into fractions and only liquid goes into the second tank. Next, wastewater without heavy elements is exposed to activated sludge involving bacteria. Next, the purified water mixed with sludge goes into the third compartment, where the sludge settles, and process water goes for further treatment or into the soil.
3. Biofilter. After mechanical filtration of the wastewater, the liquid passes through a film that contains microorganisms. Organic substances are oxidized with the help of microorganisms and serve as energy for them. Part organic matter bacteria are used to increase mass and thereby settle at the bottom. Purified water remains on the surface.

Above were the types of domestic sewage systems discussed that are suitable for a country house. And cleaning methods help preserve the soil and the environment.

Reliable and uninterrupted operation of the sewerage system, especially in country houses, provides the necessary level of comfort and convenience of living. The operation of this system is as important as water supply and heating. Conveniences on the street are no longer suitable for anyone. Many people want the same level of comfort in country houses as in city apartments. Let's consider what types of sewage systems exist and which ones are suitable in private homes in our country.

There are three main types of sewer systems:

• industrial sewerage system, which is designed to collect and treat wastewater in production;
• storm sewers serve to drain wastewater that is formed due to precipitation;
• household system, which can be centralized (for the whole settlement) and autonomous (for one or more private houses).

In addition, all of the above types of sewerage systems are divided into internal and external. Internal system- a set of devices and pipelines for household plumbing that are installed inside a private house.

External sewerage includes pipes, pumping stations and treatment facilities, that is, what is located outside the walls of the building.

• The external sewerage system, in turn, is divided into: general alloy system, where economic, household and rainwater
• retracted together;
• a separate system in which rainwater flows are discharged separately from household wastewater;

semi-separate system - in which wastewater is discharged separately, and then all types of wastewater are combined in one treatment collector. The types of sewer systems used in country houses or summer cottages are rarely equipped with a centralized system for the collection, storage and disposal of wastewater and waste. Therefore they are used autonomous species

• drainage:
• a cesspool is the cheapest type of sewage system, but is extremely inconvenient to operate and clean; biological toilet – convenient option for small cottages, in big house
• practically not used;
• a septic tank is the most acceptable option in terms of price and maintenance costs; filters and sewerage installations

designed for wastewater treatment using biological agents.

Also, types of sewerage differ in the method of wastewater disposal - gravity system and using pumps.

The use of drainage type sewerage is justified in areas with deep groundwater.

The principle of its operation is that the cesspool is built deep, and the bottom consists of a natural filter. It uses alternating layers of gravel and sand. Wastewater, passing through this filter, is purified and then goes into the soil. Not recommended for use in drainage system

waste water from the toilet. This type of sewage system is best used for bathrooms, showers and baths. Another variant drainage sewer designed for collection and disposal excess water from the site of a private house. Pipes with holes are buried in the ground through which moisture enters. Excess water is then drained into wells, cesspools or septic tanks. So in a simple way the water level in the soil is regulated. This system is also used to collect rain and melt water. Plastic pipes should be used, since metal pipes

They won’t last long in the ground, and they are much more expensive.

Autonomous sewage systems During construction autonomous systems The principle of its operation is the natural movement of wastewater under the influence of gravity . Pipes must be laid with a slight slope. Such a system is inexpensive to construct, operate and maintain. Its use is convenient; there is no need to use additional energy to drain water.

However, in this case the storage tank cannot be placed far from home. The level of inclination of pipes directly depends on their size and diameter. Optimal inclination should be approximately 1.5 to 3 centimeters per linear meter pipes. With a lower slope, the movement of wastewater will be difficult, and congestion and traffic jams may occur. If the slope is too large, solid waste fractions in the form of oils and grease can settle on the walls of the pipeline, which will also disrupt the operation of the entire system.

Before constructing a wastewater drainage device, it is necessary to carry out a hydraulic calculation sewer network. This calculation is quite complex, so it is carried out by specialists. There are cumbersome formulas by which the volume of expected wastewater is determined. Accurate sewerage calculations are made only in large or centralized systems. IN country house It is necessary to know and carefully consider the following quantities:

• diameter of drain pipes;
• pipeline slope;
• the speed and degree of filling of the storage tank, which depend on the number of residents and the number of points and drainage units.

Knowing approximately these values, it is not difficult to make a hydraulic calculation of the sewerage system.

One type of autonomous sewage system is a pressure system. It uses sewerage installations that are used in places where the level storage system higher than private house water consumers. For example, the toilet or bathhouse is in the basement or ground floor. The wastewater will not flow out of there by gravity, so a device with a pump is used to pump the wastewater. Installation may have cutting mechanism for grinding solid waste fractions.

Construction of a cesspool

A cesspool is inexpensive and simple means for removing wastewater from the house. To do this, it is necessary to place a tank in a pre-dug pit or build it from brick or other materials. An easier way is to buy a ready-made plastic container the right size and bury it in the ground. First, a pipeline with a certain slope must be connected to the tank.

The disadvantage of this system is the high frequency of pumping out wastewater.

If the container is made without a bottom, it will cause damage to the site and sources drinking water. Therefore, it is best to make a septic tank, which includes a sealed container for collecting, storing and pumping wastewater. And water purification should be carried out using biological drugs. Moreover, purified water can be used for various household needs and watering the garden.

The sanitary sewage system of a bathhouse is usually constructed of a drainage type. This is the simplest, most convenient and cheapest device. The wastewater flows into the tank by gravity. To do this, it is necessary to make holes in the floors of the steam room and washing compartment into which to connect drain pipes and place them in the ground with a slope. To collect wastewater, it is recommended to do drainage well. Several layers of sand and gravel should be placed at the bottom of the well to filter the wastewater.

Construction of storm drainage

When building a country house, you should provide and build storm sewer. The main task of storm drainage is to collect and drain melt and rainwater to protect the foundation and walls of the building. Wastewater from the roof and site enters a storage tank, is poured onto the soil, as it does not pose a threat to the environment, or is collected in special tanks for watering the garden and garden. There are three types of storm drainage:

• a drainage system in which water enters the pipes and is discharged to the right place;
• water is drained away from the house using special trays, but in winter these places freeze;
• water receivers are installed under each pipe, which are combined into one common system collection of wastewater.

What types of sewage system to choose in a private house must be decided before the construction of the building in the absence centralized system disposal of wastewater and waste. Some homeowners mistakenly believe that building a regular cesspool without a bottom will cost them much less. At first, yes, the costs will be lower. However, over time, after about five years, this pit will have to be built in another place, since every year it will be necessary to call the sewer truck more and more often for pumping.

That's why modern devices for wastewater treatment using biological preparations will help create convenient system sewer and avoid problems in the future. Conventional cesspools last approximately five years. A modern systems sewerage at good service about fifty years . Obviously, the choice is up to new devices.

Therefore, even when designing and building a bathhouse sewerage system, everything should be carefully weighed and thought through. It is necessary to plan costs, think not only about comfortable living, but also about the environmental situation on the site