Scheme of a two-chamber septic tank made of concrete rings. Do-it-yourself septic tank from concrete rings - step-by-step instructions with video materials. How the septic tank is launched into operation

More and more people who acquire country houses are thinking about comfortable living, which is impossible without wastewater disposal.

The most popular are tanks made of concrete rings, because this traditional material has many advantages.

The popularity of concrete rings for the construction of an autonomous sewage system is associated not only with traditions, but also with several positive qualities:

Concrete products have a relatively low price. The materials for the construction of the tank are cheaper than a ready-made station for cleaning their plastic.
Concrete is a durable artificial stone that is resistant to temperature extremes, soil pressure, and large volley discharges.
Such rings are durable, and the containers made of them are capacious.

Negative qualities such septic tanks have no less:

Due to their heavy weight, it is necessary to hire special equipment for the delivery and installation of concrete rings.
Piping holes are difficult to make in concrete.
Cracks and chips form in the walls and butt joints, which leads to the ingress of drains into the ground. Therefore, a regular inspection of the reservoir is required.
Such treatment facilities, due to their large diameter, require large areas.
A common problem with these septic tanks is the stench.

If for you the advantages of concrete treatment tanks outweigh the disadvantages, then before proceeding with the purchase of materials and installation, it is necessary to draw up a project correctly.

How to calculate the volume of a septic tank?

Most often, a concrete wastewater treatment system consists of from two tanks:

in the first, processes of precipitation of large suspensions and anaerobic decomposition of contaminants take place;
after that, the partially clarified water enters the stage of soil filtration, most often representing a filtration well.

Rarer, but perfect is the design from three tanks, while in the second, you can arrange an aeration system. In addition, three-chamber septic tanks are installed if the daily flow rate exceeds 1 m 3.

The volume is calculated for the first tank for two-chamber septic tanks and for the first two tanks for a three-chamber device in accordance with the required capacity. Based on the result obtained, the required number of rings is calculated.

Calculations are made in accordance with several rules:

To calculate the approximate daily volume of wastewater, you need to multiply the number of residents by 200 liters. It is recommended to increase the resulting value by 10-15%, this will allow for the arrival of guests.
If the calculated volume turns out to be less than 5000 liters, then it is multiplied by 3. At a higher value, the volume must be increased by 2.5 times. This allows you to take into account the residence time of the effluent in the septic tank, which is usually 3 days.
The volume of one ring is calculated by the formula for the volume of a cylinder:

V = 3.14 x H x D 2/4... In it D Is the diameter of the ring, and H- his high.

The topmost element does not take into account 2/3 of the volume.

Knowing the size of the ring and the number of residents, it is easy to calculate the required number of concrete products, choose a place, purchase everything you need and start installation.

How to make a septic tank from concrete rings: step-by-step installation instructions

In addition to calculations, preparatory work also includes - choice of location and consideration of natural features.

the concrete cascade for protection from atmospheric moisture and ensuring the gravity movement of wastewater inside the treatment system should not be located in a lower relief;
there must be at least 5 m between the cleaning device and the foundation;
distance to underground drinking springs - 50 m, and to reservoirs and watercourses - 30 m;
if the supply pipeline has a length of more than 10 m, then a manhole must be installed on it;
with a high groundwater level and poorly permeable soil, the filtration well must be replaced with one of the types of filtration fields or a storage tank;
it is important to take into account the possibility of a sewer truck approaching;
pipelines must run below zero soil temperatures.

Having chosen a site for the installation of tanks, you can proceed to purchase of equipment and preparation of the entire tool:

First of all, you will need reinforced concrete rings.... For the sump and biological treatment tank, the first element can be purchased with an existing bottom, or during the installation process, fill it yourself. Floor slabs are also required from concrete goods.
Need to buy cast iron or plastic hatches in an amount equal to the number of tanks.
Ventilation pipes and connecting chambers to each other and to domestic sewers and their fittings.
Sand for leveling trenches for pipes.
Crushed stone for a filtration well.
Waterproofing for joints between the rings, for example, bitumen.
Roofing material for external waterproofing of tanks.
Cement, liquid glass.
Devices for cutting and joining polyethylene pipes.
Shovel.
Trowel and brush.

It is also important to agree on the hiring of lifting and digging equipment. You can prepare the pit manually, but it will take much longer.

Excavation

Before digging, markup is usually done:

a peg is placed in the center of the proposed pit;
a string is tied to it;
a second peg is tied to the free end of the rope at a distance equal to the outer radius of the concrete ring, plus another 20-30 cm;
the resulting system outlines the contours of the pit.

This is done for each tank. The depth of the pit should be slightly greater than the total height of the rings, since you need to take into account the preparation of the bottom. The bottom is leveled at the building level and rammed. Then the concrete base is poured, if rings with a dead bottom are not purchased.

For the filtration well, a cement base is not needed; instead, a crushed stone filter is poured.

At the stage of excavation, trenches are prepared for the inlet pipeline and pipes connecting the tanks, not forgetting about a slope of 5 mm for each running meter. The bottom of the ditches is covered with a layer of sand of 10 mm.

Now you can proceed directly to the installation work.

Installation and connection of rings

With the help of a crane, the rings are released strictly on top of each other, processing the joints between them with a mixture of liquid glass and cement.
From the inside of the container, the seams are additionally covered with bitumen for waterproofing and connected with metal staples for structural strength.
An external sewer pipeline is brought in.
In the walls of working containers make holes for inlet and connecting pipes... The junction of 1 and 2 tanks should be 0.3 m higher than between 2 and 3 chambers.
Fittings are installed in the holes.
A ventilation pipe is mounted to the first tank..
Lay the connecting pipelines.
Dock the reservoirs with all pipes. All joints are treated with a sealant, for example, liquid glass.
Cover all containers from the outside with roofing material.
If necessary, the compressor is released into the second tank and activated sludge is loaded.
Install ceilings and hatches.
Cover with insulation and backfill.

The device is ready for use. The simplest septic tanks can go into operation within six months. This procedure is accelerated by adding special bacteria to the containers. Correct operation depends on regular maintenance.

How to maintain a concrete septic tank?

System maintenance sewage treatment includes several activities:

regular control of the amount of sediment during inspection and using a wooden stick, which is lowered into the septic tank to the bottom;
sludge pumping;
checking the purity of the water in the filtration well;
once every 5 years - cleaning the soil filter;
once a year - checking the compressor in the aeration tank.

The cost of a concrete septic tank

One of the advantages of concrete septic tanks is the low price of rings. constituting the main expense item. One concrete ring with a diameter of 1000 mm and a height of 900 mm without a bottom costs about 2 thousand rubles. The same ring with a bottom costs 1000 rubles more.

For a family of three, about 7 concrete rings are needed for a two-chamber septic tank: 4 - for the first container, 3 - for the second. We also need 2 floor slabs with a total cost of 3400 rubles, and 2 hatches, 1000 rubles each. The total price of all products will be 20,400 rubles without delivery.

Truck crane services cost on average 1000 rubles per hour. You also need to take into account the costs of concrete, waterproofing, crushed stone and sand, plastic pipes. The finished cost of a self-installed two-chamber septic tank will be about 25-30 thousand rubles. This is if you dig a pit by hand.

Contractors offer a turnkey installation of sewage from concrete rings for at least 50 thousand rubles.

Price of finished plastic anaerobic device wastewater treatment with soil post-treatment with a similar performance is at least 36 thousand rubles... Moreover, it is more durable. It is much easier to install it on your own.

Difficulties in installation and operation can arise only in heavy soils with high GWL. In some regions of the country, the cost of delivery will also be significant. In other cases, it is better to prefer a plastic apparatus to a concrete product.

Watch a video on how to make a septic tank with your own hands:

Most private houses do not have a central sewerage system, which leads to significant difficulties with wastewater disposal. How to be in such a situation? In such cases, an autonomous sewerage system is organized: a centralized collection of effluents from all household and outbuildings on the site is carried out, which are removed to a cesspool.

The most common cesspools, but time does not stand still and septic tanks have replaced them. Septic tanks are prefabricated plastic, as well as with deep cleaning stations.

Their disadvantage is the very high cost. An alternative option is to install a septic tank made of concrete rings.

Pros and cons of a concrete septic tank

Positive sides:

Reliability of construction. Reinforced concrete has high strength, durability and is able to withstand aggressive environments.

The overflow septic tank made of concrete rings is completely autonomous, it does not require additional elements for functioning, such as: electricity, pumps, drainage installations, tanks for aeration and bacteria, etc.

The possibility of building septic tanks of various sizes and types. This is due to a wide variety of reinforced concrete rings: the diameter of the rings ranges from 0.5 to 2 meters. The height of the rings has two options - 0.6 and 0.9 meters.

You can build a small septic tank yourself, even without the involvement of heavy equipment. Installation does not require special skills and knowledge.

The septic tank is easy to operate - no human participation is required.

A minimum set of materials and tools is required for construction.

Negative sides:

For the construction of septic tanks of large capacity, manipulators are required. This is due to the large mass of concrete rings and slabs.

Installation requires at least two people. Such septic tanks require periodic cleaning.

Scheme and operation of a septic tank

Before starting work, it is necessary to determine the location and the schematic diagram of a septic tank made of concrete rings. It is worth remembering that a concrete septic tank should be located at least 5 meters from the house, at least 2 meters from outbuildings. If there are local sources of water supply: 30 or more meters from wells and wells.

The minimum distance between the septic tank and the roadway is 5 meters. The septic tank should be located directly on the site.

Septic tanks are single-chamber, two-chamber and three-chamber. An example of each type of septic tank made of concrete rings can be viewed in the numerous photos of our selection at the end of this article.

The construction of more chambers is not advisable. The most popular are two-chamber septic tanks. Such septic tanks consist of two wells, between which a connecting pipe is located in the upper part.

The first well receives wastewater collected from all sources in the house. It is sealed (has a concrete bottom). As the first well is filled, the drains settle, the effluent decomposes into a liquid, solid and gaseous part.

The solid part accumulates at the bottom, the liquid part is at the top, and the gaseous part is removed through the ventilation riser located at the very top of the septic tank (a hole is made in the well slab, the pipe is removed 0.5-1.0 meters above the ground).

Reaching the mark of the connecting pipe, the liquid part is poured into the second well. The second well has a drained bottom (there is no concrete slab in the bottom - instead of it there is a crushed stone pad).

As liquid effluents enter, they accumulate, settle and are absorbed into the soil. How to make a septic tank from concrete rings? It all starts with calculating the required volume.

Required volume

Depending on the volume of wastewater, the total volume of the septic tank is also selected. For a standard family of 3-4 people, a septic tank of about 6-9 cubic meters is required. The calculation is based on the conditions of water consumption per day per person: 200 liters / day, as well as the minimum volume of the receiving drainage pit per three days.

If there are 4 people, we get the total maximum volume of waste water, taking into account a stock of 200 liters - 1 cubic meter. This means that the receiving well must be at least 3 cubic meters.

The second well is usually made with the same volume. If there are more people, they increase the number of rings in the septic tank, their diameter, and also erect additional chambers.

The maximum volume of a three-chamber septic tank can reach 45 cubic meters of usable volume.

Preparation

After determining the place for the septic tank and calculating the required volume of effluent, you can easily determine the required volume of the septic tank. The number of concrete rings, bottom slabs and coverings depends on its volume (ready-made rings with bottoms can be used).

After purchasing and receiving all materials, you must:

Prepare the pit. The pit should be dug for all chambers at once (large pit), with a margin for mounting rings of 0.5-1 meter on each side. The depth of the pit should correspond to the full height of the septic tank.

Align the bottom of the pit and fill it with a sandy pillow, 0.1-0.2 meters thick. Tamp the pillow.

Digging of the pit should be carried out only in a mechanized way. When constructing septic tanks of small volumes (up to 4 cubic meters), you can do it manually.

Purchase cement, sand, crushed stone, sewer pipes, bitumen mastic, a manhole. Make sure you have the necessary tools.

Septic tank installation

For the construction of a septic tank, you need special equipment and at least 2 people. Installation is carried out from the bottom. The bottom is set to level. Further:

Installation of rings, coatings is carried out using manipulators. The rings are set on a cement-sand mortar, as well as all roof slabs.

After installing the rings, perform a coating waterproofing, protecting from moisture both the septic tank itself and preventing the ingress of drains through the walls of the septic tank into the ground.

Place the connecting pipe between the septic tank wells at least 0.2 meters below the inlet pipe from the house to the receiving well. Make a drained crushed stone bottom in the last well.

Seal the edges of the hole for pipes in the walls of the septic tank with cement mortar. After it has hardened, thoroughly coat this place with bitumen.

Maintain the slope of the sewer pipes within 3-5%.

Conclusion

A concrete septic tank does not require a lot of time and money. Is a budget option for solving problems with sewerage.

Installation of small septic tanks made of concrete rings can be done by hand, without the involvement of special equipment.

At the end of the work, the septic tank must be equipped with ventilation pipes, the rings are fastened together with longitudinal vertical corners or plates. It is most rational to place a septic tank at the lowest point of the site.

Photo of a septic tank made of concrete rings

If plastic septic tanks do not inspire confidence in you, make your own, with aeration and separate chambers. For these purposes, the most profitable option is concrete rings, and today we will tell you how to properly install them, waterproof them and lay them inside the communications network.

Scheme and principle of operation of a septic tank with separate chambers

Septic tank is a generalized definition of multilevel wastewater treatment systems, which are based on the use of natural biological processes. Unfortunately, most of the "branded" products are just an attempt to standardize the work of the WWTP, although such structures have always been erected only according to an individual project, which takes into account:

features of soil and relief;
ground water level;
temperature regime;
chemical composition of effluents.

A number of more specific indicators are often added to this list.

In home construction, a septic tank made of concrete rings requires a sensitive approach, organization and planning of the structure in all possible modes, including emergency. All processes related to both water clarification and the protection of cameras from negative external influences must be worked out to the smallest detail.

The first chamber is a sealed column of the primary clarifier (PO). Its volume is determined at the rate of 200 liters per person per day for at least three days in case of abnormal work. The capacity of the software is equivalent to the capacity of the second chamber (reactor or aeration tank), respectively, it is necessary to take into account the possibility of three-fold salvo discharge, protecting the septic tank from self-flooding.

A conventional septic tank uses the gravitational principle of moving water between chambers and does not contribute to the rapid development of bacterial colonies. Septic tanks equipped with a system of aeration and waste movement have an accelerated treatment mode due to the attraction of aerobic microorganisms into the process, but they require expensive technical equipment and are volatile: up to 1.4 kWh / day and about 3-5 kWh / day at working heating.

As a warning, we will make a small excursion regarding the preparation for the arrangement of a septic tank. Lay the underground part of the septic tank inlet line with a HDPE pipe 125 mm SDR 17. Its inner diameter allows you to pull about 50 cm at the end of a 100 mm sewer pipe, free from the socket. It is better to drain the clarified water with the same pipe, but with a diameter corresponding to the drain pump fitting.

What rings and how to dig them in

One of the key properties of a septic tank is the tightness of the PO chambers and aeration tank. Without this, the runoff will seep into the top water, polluting drinking water sources, deteriorating soil characteristics, which will attract the attention of sanitary and epidemiological control services.

When dealing with rings, it is difficult to achieve a deaf waterproofing: the winter heaving breaks the joints, the rings are displaced from the ground movements. High-quality insulation materials alone are not enough, a ring fastening system is needed.

Another problem with any sealed chamber is that its equivalent density may be lower than the density of the soil, therefore, over time, the septic tank will begin to squeeze out. All this leads to the conclusion that a standard ring well shaft using the sequential digging method is clearly not enough.

Rings must be used with a quarter (lock) for a secure fit. First, a hole is dug to the required depth, the diameter is one meter larger than the rings. The bottom is poured in two stages. The first lower layer is 80 mm, reinforced with mesh, with four anchor inserts diametrically distant from the center to the outer radius of the ring. The second layer is poured the next day with sand concrete 30 mm, then, before setting, the lower ring is lowered into the pit and installed between the mortgages.

Previously, the rings of the first two chambers must be treated with one or two layers of coating waterproofing. The locks on the ends are opened especially carefully, and a fresh layer of mastic is applied when installing each new ring. It is recommended to fasten through the walls of U-shaped brackets with thread at the ends from the final calculation every 40 cm.

After installing the shaft, it is covered with a cap with an outlet on the sides of at least 150 mm at a level of 100-120 cm below the ground. 16 mm holes are drilled according to the location of the embedded elements in the cap, then the container is pulled together with thermo-reinforced reinforcement with a diameter of 14 mm on threaded bends. The throat of each chamber can be assembled from rings, but with a high level of groundwater, it is better to cast it monolithically with a cap or arrange a clay lock at the level of the top water.

From the outside, the columns are covered with a layer of foamed polyurethane foam, possibly with a foil backing. Not for the purpose of warming, but as a means to compensate for the swelling of the soil, and prevent it from freezing to the rings. The remaining space can be filled with road rubble, but often it is filled with excavated clay - it depends on the type and composition of the local soil.

Not all containers are equally sealed

The water leaving the second chamber is 99% free of solid particles and fat, but it is biologically contaminated and requires additional treatment in the soil layer. So, contrary to the “heralds” from marketing, it is categorically not allowed to dump water from the septic tank onto the relief.

The function of the filtration field is perfectly handled by a well made of perforated rings. You can dig in the rings sequentially, but it is still better to start from the pit and arrange a 20-cm dump on the sides with rubble, anticipating the silting of the holes. To simplify excavation work, you can replace one deep container with a pair of smaller ones. It is also preferable to remove the filter well from the septic tank chambers by 5-7 meters so that the soil around the chambers is less saturated with moisture.

When laying the upper rings, do not forget to leave the mortgages connecting the first chamber with the second and the second with the third by means of 110 mm PVC pipe lengths located with a difference in level of 50 cm.Place an HDPE pipe with a diameter of 70 mm from the bottom of the second chamber to the middle of the first one. Also, do not forget to connect the aeration tank with a HDPE pipe to the filter well. The outlets of pipes in the first chambers are sealed and sealed, then they are completed with vertically oriented tees so that the overflowing liquid is taken from a layer 2-3 meters below the surface, where there is no solid silt and light fragments.

1 - sewage inlet pipe; 2 - tee; 3 - primary sump; 4 - aerotank; 5 - drainage well; 6 - HDPE pipe Ø110; 7 - HDPE pipe Ø70; 8 - crushed stone (gravel)

Septic tank aeration system

To maintain the vital activity of aerobic bacteria, air must be periodically passed through the treated wastewater - about 1300 l · m 3 / h. The more the air bubbles are atomized, the more efficiently and faster the aeration takes place. Diaphragm diffusers used in fish farms to supply oxygen to pools do this well. They need to be located one meter from the bottom of the aeration tank in an amount of one to three pieces, depending on the size and performance of the entire system.

1 - compressor; 2 - silicone tubes; 3 - membrane diffuser

The diffusers are connected by means of silicone tubes led out through the overflow pipes to the neck of the container. The compressor can be located either on an equipped site inside the aeration tank, or in a caisson equipped next to the tanks.

Moving masses between chambers

The septic tank must be supplied with a submersible slurry pump, which will not only prevent flooding, but also help with periodic cleaning of accumulated waste sludge. By default, it is suspended in the middle of the second tank, but the float is brought out half a meter above the outlet. So the pump will urgently get rid of excess clarified water by dropping it into the filter well, and will not allow the septic tank to flood itself.

1 - cable; 2 - float; 3 - drainage pump; 4 - tubular diffuser

Activated sludge is pumped into the primary sump through the second pipe between the chambers, which accelerates the growth of bacteria and the operation of the entire septic tank. In order not to use another pump, the end of the pipe is smoothly lowered 30 cm from the bottom, and a productive tubular diffuser is installed inside, which works as an airlift with a lift height of up to two meters.

A comfortable existence is impossible without sewage. In a private house or in the country, this is usually a cesspool or septic tank. The second option is more environmentally friendly and safe - a septic tank. It decomposes waste into insoluble sediments, which fall to the bottom, forming silt, and fairly clean water, which is usually discharged into the ground for further additional purification. Probably the most popular version of this installation is a septic tank made of concrete rings. The technology of its construction is simple, you can build it yourself, the cost is relatively low. This explains its popularity.

Device and principle of operation

A septic tank made of concrete rings is best placed on well-draining soils that are not prone to frost heaving. The body of a septic tank consists of several rings placed on top of each other. Even if they have tabs for better fixation, even if they are stapled together, the frost heaving will move them. The result is leakage and costly repairs. And not the fact that after the repair it will not move again. Therefore, it is recommended to make a septic tank from concrete rings on sandy or sandy loam soils.

If the soils drain water well, the groundwater level is low, it makes sense to drain the water from the septic tank into the drainage column. Such a device is the most optimal. At a high level of groundwater, treated wastewater is diverted to drainage fields. Their device requires large areas and no less substantial amount of earthwork, but sometimes only such a system works.

The septic tank diagram is shown in the photo above. It consists of two working chambers connected by an overflow. The cleaning process takes place in them. The third column is a drainage well (instead of it there may be a filtration field), through the holes in the lower part of which purified water goes into the ground. This is briefly about the device of a septic tank made of concrete rings. Now about the process itself.

The effluent enters the first chamber. It is sealed, with the most limited air flow. Under conditions of oxygen deficiency, the main decomposition process takes place in it. Organic matter is processed by microorganisms and bacteria. Organic matter breaks down into more or less pure water and insoluble substances, which precipitate and accumulate at the bottom of the chamber.

Through the overflow pipe, water with less contamination enters the second chamber. The purification process continues in it, but here it takes place with the obligatory participation of oxygen. Therefore, the second chamber is equipped with a ventilation pipe. Here the remains of organic matter decompose and settle to the bottom. Almost pure water is discharged into the drainage column and goes into the ground, where their final post-treatment takes place.

The dimensions of the septic tank chambers and their number

In order for the drains to be effectively cleaned, they must be in the septic tank for at least 3 days. Based on this, the dimensions of the cameras are determined.

How to determine the volume of a septic tank

According to the standard, the minimum volume of the septic tank is three times the daily water consumption. One person counts 200-250 liters. In total, if you have 4 people in your family, the minimum volume is 3 cubes. The storage tanks, that is, the first two chambers, should hold so much. The third - the filtering column - does not in any way apply to accumulative ones, therefore it is not taken into account.

This was about the standards that are in force in Russia. In Europe, the minimum volume of a septic tank is 6 cubic meters. And many people think that such dimensions are more "correct". Large volumes of wastewater are stored in storage tanks longer, which means they are cleared better. When using the native standard, in the event of the arrival of guests, it is easy to "overflow" the norm. As a result, untreated wastewater will end up in the filtration column, which will pollute it and the entire surrounding area. Elimination of the consequences is an expensive and complicated procedure.

Even if you decide to adhere to Russian norms, if you have a bathroom, washing machine and dishwasher, you need to increase the volume at least by the size of the salvo discharge of all these devices (bathroom - 300 liters, washing machine and dishwasher 50 and 20 liters, all together - we will consider 400 liters or 0.4 cubic meters).

In accordance with the calculated volume, the sizes of the rings and their number are selected. The diameter of the concrete ring can be from 80 to 200 cm, sometimes there are rings with a diameter of 250 cm. The height is from 50 cm to 1 m. The table below shows the dimensions of standard reinforced concrete rings, their markings, weight and volume. In the column "dimensions", the outer diameter, inner diameter, and height are indicated through a fraction. All values are in millimeters.

When calculating, keep in mind that the actual volume of the column must be higher than the calculated one - the drains never completely fill, but rise only to the level of the installed overflow pipes. It is up to the level of these pipes that the calculated amount of drains should be placed.

Number of columns

There can be three storage chambers in a septic tank (except for the filter column). Sometimes such a device is more practical - if it is required, for example, to install six or more rings in each of the columns. The depth of the pit in this situation turns out to be large. It is more convenient / more profitable to make three columns of four rings.

There may be a reverse option - a small volume of a septic tank is required. This happens at dachas of periodic visits with a small number of summer residents serving it. In this case, the column can be assembled alone by dividing the rings inside with a sealed partition. and making the overflow hole at the required level.

How to do

The most common construction principle is linear. All columns are lined up. Accumulative reservoirs can be located nearby, and the filtering one - at some distance from them and preferably farther away so that the flowing water does not saturate the soil and does not freeze, increasing the phenomenon of frost heaving.

General rules for storage columns

It is better to take rings for a septic tank with locks. They are easier to install, they are less likely to move with frost heaving, the degree of sealing is higher. Before installation, it is advisable to treat them with a coating waterproofing. Bituminous mastic and cement-based deep penetration impregnation (Penetron type) give good results. With this treatment, nothing will leak out of the septic tank, and groundwater will not get inside.

The rest of the rules for constructing a septic tank from concrete rings are as follows:

The optimal distance between the storage columns is 0.5 m. This gap, filled with soil, will act as a buffer during ground movements.
A layer of crushed stone about 20 cm thick is poured and rammed at the bottom of the pit. It is rammed to a high density, better - using a powerful rammer. The filling surface should be strictly horizontal and flat, without drops. The plane is checked using a building level at least 1.5 meters long (preferably 2 meters).
On tamped crushed stone:
All subsequent ones are installed on the first ring. The joint of each is carefully sealed. You can lay out a layer of the same Aquacement before installing the ring on the side. After installing all the rings, the joints are once again coated with a waterproofing solution from the inside and outside. It is impossible to use toxic compounds inside - bacteria that respond to the decomposition of bio-inclusions will die and the septic tank will not work.
For a more durable fixation of the rings, they are connected with metal brackets (installed outside. The places of the “entrance” of the brackets are concreted, coated with waterproofing.
It is advisable to insulate the upper part of the septic tank (above the freezing depth). For this purpose, a polystyrene "shell" is used or expanded polystyrene cut into strips is glued. The drains, of course, are warm, but in severe frosts there is a risk of ice crust formation, which reduces the effectiveness of purification. Therefore, insulation is desirable.
For reasons of economy, necks are made at the top of the septic tank columns. Sewer pipes along the site are usually buried below the freezing depth of the soil. It is 1.5-1.7 meters in Central Russia. And they must also go with a bias. Let the slope be small, but since the length of the track is large (no closer than 8 meters from the house), quite a decent amount runs up. In total, it turns out that the sewage system enters the septic tank near the 2 meter mark and the entire part of the column, which is located above, is empty. So they reduce it with the help of golovans, which can be done:
The overflow pipe between the chambers of the septic tank is made with a diameter of 110-120 mm. It can be made of asbestos or plastic. Its entrance is carefully sealed.
The inlet pipe that comes from the house and the overflow pipes between the chambers are equipped with tees. This directs the effluent downward, preventing the crust from eroding (it is needed for better effluent treatment). Sometimes tees are equipped with pipes going down.
The location of the overflow pipes is determined by the level of the inlet pipe (from the house). The overflow on the opposite wall should be 5 cm below this level. Between the second chamber of the sump and the filtration well, the overflow can be done at the same level, or lower it by the same 5 cm.

Features of the construction of a filtration well

When constructing a filtration column, the foundation pit is dug up to soils that drain water well. A layer of crushed stone 20-25 cm thick is poured onto the bottom, on top of it is a layer of sand 30-40 cm thick. Rings without a bottom are installed on this backfill. In some cases, a perforated ring is placed - holes of at least 30-50 mm in diameter (there are, by the way, factory ones).

When installing a perforated ring, it is also advisable to replace the soil around it with crushed stone. This is necessary for the water to drain better. The rest of the structure of a filtration well made of concrete rings is the same.

How to bury septic tank rings

The most common way is to dig a common pit, install rings with a crane, lay overflow pipes, seal up all joints / cracks, seal, insulate, then fill and compact the soil. All is well, except that the amount of excavated soil is very large. To make everything fast, it is easier to use the services of an excavator. Manually, with your own hands, it takes a long time, but if you hire a team of "cops", it will turn out to be long and expensive. Typically, the cost of a team of diggers is comparable to the cost of calling for special equipment. It's just that the technician works for several hours, and the team - for several days. But, perhaps, this situation is not in all regions.

There is a second way to bury a concrete ring - methodically remove the soil inside the ring and under the wall. Under its own weight, the ring falls down. But only rings without a bottom are buried in this way. The bottom will have to be poured later and it will be exclusively inside the ring, which greatly reduces the reliability of the septic tank. In addition, with this option, it is impossible to insulate the septic tank, except to dig it out to the depth of freezing. We'll still have to dig trenches to lay the overflow pipes. A rather problematic method for septic tanks, but you can also use it.

Economical septic tank made of concrete rings

The linear arrangement of the columns of the septic tank requires a solid area, you have to take out a large amount of land. Also, each of the columns must be equipped with a neck, which further increases the cost of the structure. There is an interesting option with the installation of all the columns in a triangle. there is already a saving of space and a decrease in the amount of land work.

The second point of saving is that the revision entrance can be made one to three rings. Only all overflows must be installed in the area of its availability. There are no other features.

The presence of a septic tank on the site is not only a matter of comfort, but also a sanitary and hygienic necessity. Such a device is required both in the house, subject to permanent residence, and in the summer cottage, where they come periodically. It is only important to choose the design that is optimal for specific conditions. . A septic tank with your own hands made of concrete rings, the layout and location of which are correctly selected, will have maximum efficiency.

It is important for those who decide how to make a septic tank from concrete rings with their own hands: the design diagram can include from one to three containers, moreover, with an increase in their number, efficiency increases, the need for the services of a sewer truck decreases, but the cost of the project also increases.

For clarity, you should consider in more detail the most complete version of the septic tank scheme from rings using three containers.

The contaminated water is collected in the first, largest reservoir, where settling and sedimentation of the largest fractions occurs, after which the partially purified water undergoes a similar procedure in the second reservoir, which structurally practically does not differ from the first one (sometimes it is advisable to make it slightly smaller in volume).

The second tank settles small inclusions, the water becomes relatively clean and enters the third tank. Its distinctive feature is the presence of a filter bed instead of a concrete bottom... Passing through the drainage layer, water gets rid of the residues of contamination and goes into the ground.

The photo shows an example of how to install a septic tank from concrete rings with your own hands - a diagram of three containers

If a two-tank septic tank made of concrete rings is chosen, the scheme can include two tanks with concrete bottoms or one with a concrete bottom and one with a filtering layer.

Single-chamber models only collect wastewater and partially precipitate insoluble inclusions. Such modifications are cheap, but ineffective and are suitable only for periodically visited summer cottages. Removal of contaminated water from a single-chamber septic tank can only be carried out using a sewage machine. A similar cleaning is required for both two-chamber and three-chamber structures, however, the required pumping frequency in these cases is much less.

For those who are looking for the simplest options, we advise you to pay attention to it, it can be done literally in one day.

About the features of the organization of the sewage system in the bath, we.

Design nuances and full equipment

In order for a septic tank made by hand from well rings not to give out its presence with an unpleasant odor and does not have a harmful effect on the composition of the soil or water in nearby water bodies, it is important not to neglect the nuances and equip the structure in accordance with the requirements.

So the drain pipe (plastic products are preferable) should have a slope of 2 cm per meter of length along the entire length and enter the concrete section no deeper than 20-25 cm from the upper edge of the upper ring. However, in practice, very often the entrance of the pipe into the section occurs much lower when digging a trench and laying pipes deeper than the level of soil freezing (approximately 1 m.)

A feature of the first section is the presence of a concrete bottom, which minimizes the likelihood of dirty runoff entering the ground. In a similar way, the first section is arranged when choosing a two-chamber septic tank, as well as the only reservoir of single-chamber models.

The scheme of a septic tank made of concrete rings for three or two containers provides for filling the bottom of the last of the tanks with materials capable of retaining large and medium insoluble inclusions, if any, and removing liquid into the ground. To do this, you can use sand, gravel or expanded clay, and the optimal solution would be layer-by-layer stacking of materials with different fractionation.

Preliminary calculations

The reason for the inefficiency of the structure or the inconvenience of its operation can be not only a violation of technology at the construction stage, but also an error in calculations when determining the required volume and the optimal location of the structure.

Based on the average volume of water consumption (approximately 200 liters of water is required per person per day), it is customary to choose the following volumes of septic tanks from reinforced concrete rings:

for 2-3 people - 1.5 cubic meters m (in this case, there is no need to install a three-chamber structure, with proper organization of drainage and cleaning, two chambers will be enough),
for 4 people the optimal tanks are 2 cubic meters. m,
when installing one septic tank for 2-3 families (10-12 people) living in separate parts of the house, a volume of at least 5 cubic meters will be required.

The volume of the septic tank is set taking into account the fact that it takes an average of 3 days for a full cycle of wastewater processing, so the tank should hold a three-day rate without the risk of overflow.

When choosing the location of the structure, the following requirements for the distance of the septic tank from certain objects should be observed:

from natural natural reservoirs - at least 30 m,
from the place of drinking water intake - at least 50 m,
from fruit trees, vegetable beds - at least 3 meters,
from the road at least 5 m (it is important to ensure the possibility of unimpeded access of large-sized vehicles, since at certain intervals it will be necessary to approach the sewer truck to pump out the wastewater, and during the cleaning of the septic tank - the disposal of the material of the drainage layer).

Installation of the structure

Advantages

Having made a septic tank from concrete rings with your own hands, you can be sure that it will be distinguished by its durability and efficiency. With proper operation, it practically does not wear out, does not deteriorate and will last for decades. At the same time, you do not have to spend a lot of money on maintenance.