Types and features of septic tanks
The simplest and most primitive septic tank is a two-chamber cesspool, the primary chamber of which must be periodically cleaned. Its disadvantages are well known - not the most pleasant smell and the release of practically untreated wastewater into the soil. Plus – relative complexity in technical implementation.
Cesspools
It is with a cesspool that great difficulties arise when choosing its location - after all, from the point of view of financial costs and effort, it is most convenient to place the pit as close to the building as possible. But the presence in such a septic tank (which is practically not a sealed container) of a considerable amount of contaminants, with a high degree of probability falling directly into the ground, dictates the need to move the septic tank as far as possible.
Cesspools will have to be cleaned quite often Source dom-expert.by
Factory-made septic tanks
The most acceptable option for incorporating wastewater into the local ecosystem is to install an industrial-made septic tank. Such equipment, due to the peculiarities of its design, is distinguished by almost ideal performance characteristics :
- light weight;
- ease of installation;
- strength of the body made of polymer materials;
- high degree of purification of contaminated water;
- complete processing of mud masses;
- complete autonomy;
- minimum maintenance.
If it is not possible to use special equipment, then, if necessary, modern septic tanks can be installed manually, but without knowledge of the technology it still cannot be done
The hardest part of the work is digging a hole for the septic tank and a trench for sewer pipes Source m.2gis.ru
See also: Catalog of companies that specialize in water supply and sewerage.
Construction of a brick septic tank
Brick is one of the most common and affordable types of building materials. Septic tanks made from it for private houses have a number of advantages. They are durable and have a reliable design. Their installation does not require the use of special equipment or the use of expensive tools. The material allows you to create structures of various sizes and shapes.
The disadvantage of septic tanks made of brick is their low insulating properties. Well walls require additional protection from environmental influences. The second disadvantage is the laboriousness of the process. It takes a lot of time to build the walls of a structure.
What is important to consider
When creating a design drawing for a 3-section septic tank, it is necessary to correctly distribute the percentage of the volumes of each compartment:
- reception collection - 50%;
- aerobic cleaning chamber - 30%;
- output compartment - 20%.
Laying a brick septic tank
This ratio of the volumes of the structure’s compartments will allow you to achieve the maximum degree of wastewater treatment. The mortar that binds the bricks is made from cement grade M 400. The best type of brick is solid clay. This type of brick is the most resistant to aggressive environments, which include sewage. Despite the strength of clay bricks, the walls of wells are plastered with concrete mortar and covered with a layer of mastic. You can replace the concrete screed with a clay solution. It has an increased degree of resistance to runoff.
For ease of maintenance of the structure, it is recommended to make the depth of the compartments from 1.2 m to 3 m. The optimal thickness of the external walls is 25 cm, internal - 12 cm. When installing a 2-chamber septic tank, the volume of the receiving compartment must be at least 1 cubic meter. and account for 75% of the total cubic capacity of the structure. The cross-section of the transition holes between the compartments is 150*150 mm. The bottom of the septic tank is concreted and waterproofed. To cover the top of the structure, it is better to use concrete slabs with holes for sewer hatches.
Concrete slabs with holes for manholes
A ventilation hole must be provided in the design. It is made from asbestos pipe. It is taken out away from the septic tank at a distance of at least 600 mm. The concrete slab with hatches is insulated and covered with soil.
Criteria for choosing a location for installing a septic tank
The choice of installation location for a septic tank, even if it is completely sealed, is determined not only and not so much by the convenience of construction work and maintenance. The determining factors here are sanitary and epidemiological standards and rules - for example, those reflected in SNiP 2.04.03-85. According to these rules, the location of the septic tank must satisfy the following conditions:
- the distance to the nearest source of drinking water (well, well) should not be less than 30 m;
- there must be more than 10 m to a stream, river or other natural body of water;
- the distance to the external walls of a residential building should not be less than 4 m;
- the boundary of the site should not be closer than 3 m;
- the nearest public road should not be less than 5 m.
In addition, a septic tank in a private house should not be located close to trees - a minimum distance of 2 m.
General rules for choosing a location for a septic tank Source agrognom.ru
Additional terms
It is necessary to take into account not only these mandatory standards (if violated, significant sanctions from supervisory authorities are possible!), but also take into account local conditions. These include both soil characteristics (depth of groundwater and soil freezing, site topography) and the presence or possibility of connecting associated utilities - some types of factory-made septic tanks are volatile and require a three-phase power supply.
The design and dimensions of treatment plants are not standardized, however, when choosing the location of treatment stations, it should be taken into account that the main drain pipe must approach the septic tank with a slope of at least 2 degrees. In other words, take into account the required pit depth and the technical feasibility of meeting it.
DIY septic tank
In Russia there are regions with very different climates. In the south you can wear a windbreaker even in winter; in the north it snows already in September. This is taken into account when determining the depth of the pit.
In the middle zone, daily discharges into the sewer system are enough to prevent a septic tank made of concrete rings or Eurocubes from freezing in winter. Additional heat comes from the activity of bacteria. For reliability, the liquid level in the tanks must be at the depth of soil freezing. Accordingly, the further north the freezing region, the deeper the station and supply pipes will be located.
But there is also a groundwater level. Spring floods should not flood the lid. She is above the ground. Accordingly, the entire structure, including supply pipes, will have to be insulated using expanded clay, polystyrene foam or polystyrene.
How to build a septic tank with your own hands
You can build a sump yourself using one of the following options:
Type 1.
The treatment plant consists of two tanks. The size of each is determined by the calculations performed. The depth of the pit is 2.5 meters or more. The bottom is covered with layers of sand and crushed stone as an infiltrate. The walls are carefully compacted.
At the next stage, formwork is built, as for the construction of a foundation. Some are limited only to the inner wall. To avoid cracks and leaks of concrete, the formwork is covered with polyethylene film in several layers. The tanks are connected to each other by a pipe.
For strength, a reinforcement grid can be mounted inside the formwork. Next, the concrete mixture is poured (1 part cement to 3 parts sand). The formwork can be dismantled after a week; complete setting of the concrete takes at least a month.
Type 2.
This option is similar to the first. The difference is that the foundation pit is prepared alone. It is divided into parts using a concrete or brick partition.
If you don’t want to pour concrete and wait for it to set, you can use other materials for building walls: Eurocubes, ready-made concrete blocks, brick, metal or plastic barrels.
When giving preference to one material or another, it is important to consider:
- how intensively the sewerage system is planned to be used;
- depth of groundwater;
- hygroscopicity of building materials, its chemical activity;
- availability of construction skills and financial capabilities. Concrete rings cannot be lifted manually. You will have to spend money on hiring a truck crane.
Below are the advantages and disadvantages of the most popular types of treatment facilities made from scrap materials.
Selection of septic tank performance
The main technical characteristic of any septic tank is its productivity, which characterizes the volume of wastewater received and processed over a certain period of time; usually within a day. It depends, first of all, on the volume of the settling chamber, and secondly, on the technology used in the treatment unit for purifying contaminated water.
Inside, the septic tank consists of several divisions, so its real performance cannot be determined based on an external examination. Source ispovednik.ru
Ventilation system
During the fermentation of waste, gases are released:
- methane;
- hydrogen sulfide;
- phosphorus compounds;
- a number of other carcinogenic substances.
They are removed from the septic tank using ventilation: a choke is installed in the last chamber. Thus, air enters the sewer through the drain pipe (part of the riser leading to the roof), passes through the septic tank and is removed through the air vent in a natural way.
If biological wastewater treatment using aerobic bacteria is used (superior to anaerobic bacteria in performance), the ventilation system is equipped with a forced supply of fresh air. This issue is solved by installing a compressor.
Scheme of the treatment system
Having decided on the volume of the settling tank, you should think over and draw up a diagram of the treatment plant, which should take into account all local features. Since installing a septic tank correctly means ensuring its long-term operation without unnecessary headaches, it is necessary to calculate all possible options.
The simplest version of the treatment system includes the following main elements:
- a pipeline connecting the outlet of the home sewer system to the receiving chamber of the septic tank;
- receiving (septic) chamber;
- pipeline from the chamber to the soil treatment plant (if its installation is planned);
- aeration fields for the final treatment of wastewater and its transfer into the ground.
Scheme for removing treated wastewater from a septic tank through a filtration field - if the level of wastewater treatment is low, then approximately once every 10 years you will have to dig up the filtration field and wash or change the crushed stone Source rinnipool.ru
What is a septic tank?
These designs appeared not so long ago. Previously, they were replaced by cesspools, in which a container was either installed or left as is. Such solutions have long been unpopular; their main disadvantages are constant soil contamination, unpleasant odors in the area, and a small volume of liquid waste that can be recycled.
A septic tank is a sealed structure consisting of several chambers connected by pipes. Its purpose is the collection and subsequent treatment of domestic wastewater. The waste liquid in this system settles, is gradually purified, and flows from one compartment to another. The greater the number of compartments, the cleaner the water becomes. Purification systems come in different types, sizes, and filtration methods may also vary slightly. The choice of structure depends on the soil on the site, on the available space, and on the desire of the owners to spend this or that amount on arranging effective cleaning.
The septic tank has several functional compartments. First, waste water enters the first chamber through sewer pipes. This is where primary settling occurs. The largest particles settle to the bottom, and fat, on the contrary, floats to the surface. Then this settled liquid flows into the second compartment. Smaller particles are filtered out in the same way. Water with a higher level of purification finally flows into a filtration well, where it is finally cleared of all impurities and then goes into the ground. Not all buildings have a third camera. It all depends on the type of construction.
Selection of materials
The main part of the septic tank is the waste chambers, which can be made of a variety of materials:
Septic tanks made of plastic
The most common material for pipelines is a polypropylene pipe of suitable diameter. It is inexpensive, light in weight, has very high strength and is easy to process. If desired, you can also use asbestos-cement, cast iron or other metal pipes - but their service life is significantly shorter than that of polypropylene, and the cost is much higher.
The septic chamber is usually made of plastic or reinforced concrete; in simple cases, brick can be used. Using iron barrels of a suitable size as containers is a bad idea: they not only rot quickly, but also pollute the soil as they rust. The ideal option is industrially manufactured septic tanks, easy to install and reliable in operation.
Construction of a septic tank for a private home - a plastic version of a septic tank Source plastlist.ru
Materials for septic tanks
To make such a cleaning system yourself, you can use concrete rings, brick, or metal. If we talk about the material of purchased models, then in this case two options are most often considered - plastic or fiberglass. However, there are also metal structures.
Concrete rings
These massive pieces are reliable and stable, which is why they often become wells and septic tanks. However, before choosing these designs, you need to know about the disadvantages. This:
- the need to ensure the tightness of the joints, but no one can guarantee that they will not leak in the near future;
- vulnerability: due to metal reinforcement, corrosion is possible, so the maximum service life of a septic tank is difficult to predict.
Another disadvantage is the weight of concrete rings. It requires the presence of lifting equipment, and its involvement will result in additional costs.
Brick, stone
This material allows you to obtain a durable, reliable and inexpensive sump. Brickwork is constructed in the pit, then it is waterproofed using bitumen and/or cement. The downside of the material is that it takes a lot of time. Such a septic tank can also fail, since its complete tightness cannot be guaranteed.
Metal
These ready-made structures have a reasonable price, however, like concrete rings, metal septic tanks are characterized by significant weight. Due to their high thermal conductivity, metal containers require insulation. Another disadvantage is the risk of distortion and extrusion. To avoid consequences, septic tanks are installed on concrete slabs.
Plastic, fiberglass
Eurocube is the first candidate for self-manufacturing a septic tank, however, such a lightweight container requires high-quality reinforcement of the bottom and walls of the pit. Purchased designs have the same disadvantages. Fiberglass products are the best option; they are not afraid of deformation or temperature changes. But they also need an “anchor”.
Installation of septic tanks
Installing a septic tank always begins with digging a pit of the required size. When installing ready-made, factory-made “tanks,” it is imperative to provide a concrete pad to which the septic tank will need to be secured so that it is not pushed out by heaving forces.
Septic tank on a concrete pad Source proseptik54.ru
In addition to the hole for the septic tank itself, it is necessary to dig trenches for the supply of sewer pipes and the removal of treated wastewater. If the septic tank will be used all year round, then the pipes must be laid below the freezing level of the soil.
The septic tank is being connected to the sewer system.
Completion of excavation work: the gap between the walls of the pit and the outer side of the walls of the box is filled with any available material; usually - with soil removed when digging a pit.
Installing the container
We lower the fiberglass septic tank onto the pre-leveled bottom. If there is water in the hole, then fill it starting from the middle section, periodically throwing the hose over the service necks in order to avoid distortion. Fiberglass partitions are load-bearing, so they will not fall when one chamber is filled to the top.
The liquid begins to flow into adjacent chambers only when it reaches the overflow. Therefore, it is necessary to fill evenly for leveling, like a boat in a lake.
Completion of septic tank installation work
Upon completion of the installation of infiltrators for volatile installations, it is necessary to connect power supply cables and ventilation ducts to them, after which it is necessary to check the functionality of the entire sewer system.
After making sure that everything is working correctly, the septic tank is insulated using thermal insulation materials (usually polystyrene foam or several layers of isolon) along the edges and on top. Upon completion of insulation, the TANK septic tank is filled with soil using the backfill method.
The installation diagram of a septic tank Tank and other products of our company may also include such elements of the treatment circuit as a drainage well, an intermediate well, filtration fields and others, the need for which is determined by the characteristics of the soil on the land plot. As a rule, such elements require the purchase of additional equipment (drainage pumps, well housings, pipelines with check valves, etc.), which can also be ordered from our sewer system installation specialists.
Each model of TANK septic tank is accompanied by a company passport, which contains clear instructions for installing the septic tank, as well as all kinds of installation diagrams. We remind you that only if all the necessary rules and recommendations are observed during the installation of the septic tank, it will be covered by a 3-year warranty, regardless of who performed the installation - the Triton Plastic installation crews or other persons.
Septic tank, fence and neighbor's plot
When planning the location of the septic tank, neighboring areas also have to be taken into account:
- First of all, you need to take into account all the same requirements that apply to your own site. So your septic tank should be located at least 5 m from the neighbor’s house and 4 m from the trees, also do not forget about the optimal distance between the septic tank and communications;
- the distance between the septic tank and the fence with the neighbor’s property is at least 2 m;
- the distance between the septic tank and the road is at least 5 m. Do not forget that septic tanks periodically require maintenance, so it is necessary to provide access for special vehicles.
Storage septic tanks
The simplest devices are designed to accumulate the entire volume of wastewater generated in the house. Collection is carried out in a sealed chamber, which, as it is filled, requires cleaning using sewage equipment. For a house with permanent residence of 3-5 people, especially if plumbing equipment and household appliances (bathtub, washing machine, etc.) are intensively used, this option is practically unacceptable. This is due to the fact that the storage septic tank will either require huge volumes of chambers, or it will have to be cleaned by calling a sewage disposal truck very often.
Homemade septic tanks and industrial production devices
On many online resources you can find instructions on how to independently make septic tanks of various types. Various materials are used for this, for example, ready-made plastic containers, reinforced concrete rings, brickwork, etc. It is argued that the quality of cleaning and performance are in no way inferior to mass-produced devices, and the cost of implementation is much lower.
In general, it is very difficult to build treatment facilities with your own hands that would meet all the needs of a permanent home. At the same time, mass-produced septic tanks have a huge advantage - their compliance with the norms and requirements of current legislation is confirmed by certificates and expert opinions. In addition, the purchase and installation of such devices require an order of magnitude less time and effort. As for savings when purchasing, the difference in the cost of materials and a finished septic tank rarely exceeds 30-50%, and the reliability of such devices is simply incomparable.
The best option for long-term operation of treatment facilities with a minimum of problems would be to order a septic tank from a manufacturer or trading organization on a turnkey basis, with the involvement of qualified specialists for installation.
