Biological wastewater treatment - the basis for the work of septic tanks
Before proceeding to the analysis of the main types of septic tank for sewerage, it is worthwhile to determine what biological wastewater treatment is, because the choice of this or that wastewater treatment plant depends on understanding this process for specific needs. Biological wastewater treatment refers to purification, which is based on the ability of various microorganisms to destroy organic compounds in effluents.
There is an anaerobic and aerobic biological purification process. During aerobic cleaning, microorganisms are clarified by oxygen. And in the process of anaerobic purification, microorganisms destroy organic compounds without access to air.
At the same time, biological purification can proceed both in natural and in artificial conditions. One can guess that the natural conditions for the destruction of pollution can be observed in the soil and water bodies in which anaerobic and aerobic processes pass, respectively. If the amount of sewage from your house is small, then the soil and water bodies are optimally cope with the process of biodegradation. If there are too many organic elements, then natural objects start to become oppressed and rot. In this case, it is necessary to provide for the construction of a treatment plant, in which the artificial conditions for the decomposition of contaminants by microorganisms prevail.
Artificial conditions are also based on aerobic and anaerobic processes, and various septic tanks can use these processes either individually or in combination. Today, two types of small treatment plants are available: aeration biological installations( aerotanks) and septic tanks of different principle of operation. Septicks are sometimes referred to as an antiseptic - this type of sewage, the principle of which is based on the neutralization of biological waste in the suburban area.
Artificial cleaning conditions differ from natural ones in that it is possible to significantly accelerate this process, while decreasing the occupied area and releasing the stench into the atmosphere. In addition, such systems are often automated, which greatly simplifies their use. Aerotenics and septic tanks differ among themselves, above all, by the principle of operation: aerotanks simulate natural processes occurring in water bodies, and septic tanks in soils.
During the selection of a particular treatment plant it is very difficult to determine its appearance. Aerotanks are often much higher in cost, they require electricity supply and contracting for maintenance. Septic tanks are easier to operate and relatively cheap.
Types of septic tanks according to the construction method
By definition, a septic tank is a small reservoir( up to 25 cubic meters), consisting of one or more chambers in which different stages of wastewater treatment take place. The so-called mechanical purification of effluent usually takes place in the first chamber, during which the separation of solid impurities from the liquid is carried out. In the second chamber of the septic tank there are biological purification processes using microorganisms. In the third chamber( if any), the post-treatment of drains usually takes place, after which the clarified waters can be discharged into the ground.
A sewer for a sewer can be built using a variety of materials. In the market there are already ready plastic containers, which can only be buried in the ground. You can build a septic tank with your own hands, using reinforced concrete rings, brickwork, monolithic concrete.
One of the simplest ways( in terms of labor) of building a sewer in a private home is to use a septic tank made of plastic.
Autonomous sewerage and septic tank - construction order
The construction of an autonomous sewer and septic tank by one's own hands is much easier if you use modern materials and tools. The procedure for constructing an autonomous sewer using a plastic septic tank is as follows:
- digging pits for a septic tank;
- creation of tranches for communications;
- selection and installation of pipes for sewerage;
- installation of a septic tank.
In order to dig a hole in which a septic tank will be installed, it is recommended to order an excavator. Creating a pit by your own hand is problematic enough. The main condition for choosing a place for excavation is based on safety considerations. It is not recommended to install a septic tank closer than five meters from the foundation of the house. In addition, free access to the septic tank of a sewage machine should be provided, which will periodically pump out sludge accumulated there.
The depth of the pipes must be below the freezing level of the ground. Based on this, trenches are created. It should also take into account the minimum slope of the pipeline system, which is 1-3% of the length of the entire pipeline. It is recommended to use corrugated sewer pipes with an external diameter of 110 mm. Such pipes are equipped with rubber seals, which create a high level of sealing, and allow the installation of the pipeline without the use of fittings.
The plastic septic tank is lightweight, so it can be installed manually with the participation of a team of 4-5 people. The capacity is first installed on the planks in front of the pit, after that the boards are removed, and the septage attached to the ropes is gradually lowered to the bottom of the pit.
Installation conditions for plastic septic tank:
- , the bottom of the pit is covered with a layer of sand or is poured with concrete;
- the distance from the pit walls to the septic tank should be 30 cm;
- if the groundwater table is high, the septic tank is attached to the bottom of the pit by straps, or the septic tank is filled with a cement-sand mortar;
- it is recommended to check the sealing of all connections before instilling a sewage treatment plant.
Thus, the construction of self-contained sewerage by one's own hands can be done in a short period of time when using as a septic tank a plastic container that can be freely purchased on the market.
