Modern private houses are just as comfortable, and sometimes even better equipped, than city apartments. The problem of "conveniences on the street", installation of bathtubs, etc. has long been solved. All this became possible thanks to the emergence of new, more practical sewage systems. You no longer need to dig a cesspool and constantly turn to vacuum trucks to empty it. An autonomous wastewater treatment system solves all problems if there is no access to centralized networks. The main thing is to choose the right option for specific operating conditions.
What methods are used to treat wastewater
There are two types of wastewater treatment - mechanical and biological. Each of them has its own advantages and features. The essence of mechanical treatment is the sedimentation of polluted waters and subsequent filtration. And for biological, bacteria are used that decompose effluents into water, gas and solid insoluble particles. The best results are obtained by a combination of both methods.
Microorganisms that process waste can be aerobic and anaerobic. Bacteria of the first type require oxygen for normal life, and anaerobes live and reproduce perfectly without it. Depending on which microorganisms are involved in the decomposition of pollution, the types and designs of sewage treatment systems differ.
For mechanical cleaning, drainage wells, filter fields and cassettes are used. The effectiveness of all these structures directly depends on the properties of the soils on which they are equipped. If the site is located on sandy soils, then the drainage well perfectly solves the problem of cleaning polluted waters. However, on clay soils, as well as where high aquifers are located, there are difficulties with filtration. Therefore, it is advisable to install a double cleaning system.
Types of wastewater treatment systems for a country house
Anaerobic septic tanks or local treatment plants (VOCs) are used to filter sewage. The general principle of operation of domestic wastewater treatment systems is as follows:
- Waste water flows through the pipeline from the house to the treatment plant.
- There is a primary mechanical cleaning due to settling.
- Simultaneously with mechanical cleaning, biological cleaning takes place with the help of bacteria.
- The second stage is post-cleaning.
- The third is filtration and discharge of clarified water.
The principles of operation of all septic tanks and VOCs are similar, but there are significant differences that may affect the choice of system. Therefore, it makes sense to compare and understand how effectively they work.
Scheme of the layout of the domestic wastewater treatment plant
Option #1: Anaerobic Septic Tanks
Anaerobic septic tanks consist of several chambers, most often two or three. The main wastewater treatment occurs during the settling and processing of organic matter by anaerobic bacteria. Mechanical cleaning and clarification of wastewater occurs in the first chamber. Further, the water flows through the overflow pipe into the next chamber, where anaerobic bacteria decompose organic matter into methane, water, solid sludge, which sinks to the bottom of the chamber.
At the first stage of wastewater treatment, they are separated by specific gravity. Heavier insoluble impurities settle, while light inclusions rise. When the water level reaches the overflow pipe located in the center of the chamber, the liquid flows into the second chamber, where smaller and lighter particles settle, which did not sink to the bottom during the primary filtration.
Self-contained sewage treatment systems are designed so that the liquid flows slowly. The slower its movement, the better. This ensures optimal conditions for settling solids. Gradually sinking to the bottom, the particles are compacted and create a layer of silt, which is processed by bacteria.
During the decomposition of substances, fermentation processes occur, and the temperature of the wastewater rises. Thanks to this, favorable conditions are created for the vital activity of bacteria: septic tanks can work normally not only in summer, but also during periods of cold snap.
The last stage of wastewater treatment is passing through special filtration fields, where inclusions that have not been processed by bacteria settle. Clarified water enters the soil filter with layers of bulk materials - sand, gravel. Here, the decomposition of substances occurs with the help of aerobic bacteria living in the soil.
Option #2: Local wastewater treatment systems
Local systems are used to treat wastewater from laundries, private houses, and industrial facilities. These are highly efficient installations in which the decomposition of substances occurs with the help of bacteria of both types - aerobes and anaerobes. To ensure the vital activity of bacteria that need oxygen, the systems are equipped with aerators.
In order for microorganisms not to die, it is necessary to control the condition of biofilters, to support them with the help of nutrients. The need for control and the high cost of biofiltration facilities are significant disadvantages. However, they are worth the investment, since the degree of wastewater treatment can reach 98-99%. A conventional septic tank cleans liquids by a maximum of 85%.
Sewage drains decompose almost completely, therefore, after filtration, water can be reused for technical purposes. It is suitable for watering garden plants. To collect water, a separate tank is installed, where it enters after treatment in VOC. When choosing a station, you need to focus on the performance of the structure.
The pipeline through which the drains flow is laid at a slight slope - 2 degrees, and if septic treatment is provided, then the angle has to be increased to 5 degrees. Systems need high-quality insulation. For this, heat insulators, sand cushions and other methods are used.
To achieve the highest quality cleaning, you can make separate systems and lay pipelines for waste and fecal water. Waste water can be cleaned mechanically and with the help of anaerobic bacteria, and for fecal it is desirable to provide an additional filter.
Scheme: design of a wastewater treatment system
Septic tank or VOC - compare and choose
The choice of sewer treatment systems for individual houses depends on the priorities of their owners. So, if the question of the cost of construction is fundamental, then it makes sense to install an anaerobic-type septic tank. It can be designed and built by hand. This is a reliable non-volatile structure that requires minimal maintenance. Cons - a lower degree of wastewater treatment than VOCs, and the large size of the structure itself.
To install VOCs, you will need much less space on the site than to install a septic tank, and the wastewater treatment is of very high quality. Soils and groundwater are completely safe, because. with proper control of the station, their contamination is impossible. There are only two significant drawbacks:
- the high cost of the building itself;
- the need for investments for normal operation, tk. having to pay electricity bills.
The best brands of wastewater treatment plants
The ideal structure is one that provides a high degree of sewage treatment and at the same time costs reasonable money. Based on customer reviews, several brands can be distinguished, septic tanks and VOCs of which are recognized as trustworthy:
- Septic tank "Favorite 2P". This is one of the best brands of septic tanks. If the rest purify wastewater by no more than 85%, then the degree of purification with the help of "Favorite 2P" reaches 90%.
- Stations "Topas", "Unilos", "Tver", "Yubas". Today, these are the most effective sewage treatment systems. They differ somewhat in design, but all justify the money invested by buyers.
There are many systems built according to the "Topas" or "Tver" type. Describing the advantages of their products, manufacturers compare their treatment facilities with stations of these brands. However, even if the seller claims that his VOC is not inferior to them, it is still better to play it safe and buy exactly Topas or Tver, and not an analogue. The difference in price may be insignificant, but the quality of cleaning is guaranteed.
Station "Topas" on the site
VOC maintenance video instruction
We offer a video tutorial on self-maintenance of VOCs using the example of the Topas station:
Buying and installing a wastewater treatment system is always a lot of money. Even if the owner of the site builds a septic tank with his own hands, large expenses cannot be avoided. Attempts to save on the quality of materials or the cost of finished structures most often turn into permanent problems with sewage. Therefore, it is worthwhile to carefully study the possible methods of wastewater treatment, choose the best option and not save on installation. Consultation of a specialist will also not be superfluous.
