How to choose a septic tank

Accommodation in your own home will be comfortable, if the hosts provided all the necessary conditions.Few people have attracted the options delivered with buckets of water from a well with a wooden toilet on site.All this is valid for summer conditions with periodic arrivals on the weekend, but it looks perfect anachronism if the family lives in the house constantly.This means that normal housing must be provided with water and sanitation.Well, if in the village it is possible to connect to the central thoroughfares and collectors.But such cases are rare, and often have to create a completely self-contained system.

Water - it is a separate multi-faceted subject, and in this case we are interested in establishing an independent sewer.The discharge of untreated wastewater into the environment - is strictly forbidden.So, you need to install special facilities or equipment for the collection, settling, purification, wastewater clarification.In practice, private housing optimal solution of this problem is the use of special tanks - septic tanks.Such an element of autonomous sewerage can be built in-house, or buy ready-made.This publication will be considered as a prefabricated septic choose, that is what the product evaluation criteria should pay special attention.

What is a septic tank.It works

Septic - an essential element of an autonomous sewer system or treatment plant.And, although it is not in itself a complete scheme of wastewater treatment, its role is very important.

The main purpose of any septic tank - is to collect all the sewage from the house (group homes), their advocacy and preliminary biological treatment of varying degrees of depth.Past this cycle effluent discharged into the device or structure groundwater filtration, or be regularly pumped out by means of special equipment.In any case, it excludes from entering the environment contaminated, representing chemical and biological hazards, sewage.Essentially

- septic tank is always isolated from the soil collecting tank, and may consist of one or more cameras.The scheme is simple single-chamber septic tank is shown below:

Sewage from homes come on the tube (item 1.) By gravity, for which a certain bias observed when laying (about 5 ° or 20 ÷ 30differential mm per running meter pipe).Chamber septic tank (Pos. 2) has a reliable waterproofing or made of completely waterproof materials.Solid inclusion

under gravity settle to the bottom as sludge (Pos. 3).Those impurities, which have a density less than water, on the contrary, float upward, forming a film or crust.Thus, spontaneously bundle drains.

In the same chamber are constant processes of biological decomposition of human waste.Activate these biochemical reactions helping special anaerobic bacteria that process organic mineral deposits on inert gases, which are discharged to the outside, and clean water.At the same time, this should lead to the destruction of all pathogenic microflora.

receive such treatment and lightening water through the overflow pipe (pos. 4) to the filter section.Water intake is organized so that it is made from the central part of the stratified fluid, preventing overflow of floating crust.For this lad supplied constantly submerged vertical portion.

Final soil aftertreatment can be organized in different ways.In this case, the filter well is shown (Pos. 5) from the bottom of the drainage layer.However, this may be a field of underground filtration using special perforated pipes.and apply filters or absorbent trenches, infiltration can purchase a special unit, the so-called "tunnel".The choice of a particular type of soil the final filtration of wastewater treatment depends on the level, type of soil, the height of groundwater, the depth freezing of the soil, etc.- In any case, this will require specialist advice.

filtration module (well, tunnel, field, etc.) are no longer considered as a septic tank chamber - a terminal link in the chain of battery drain.Sometimes, when using a multilevel cleaning of septic tanks, storage tanks are used, even the water of which can be consumed, for example, for irrigation infield.

Single-chamber septic tank, it must be said, does not have a high degree of wastewater treatment.They are commonly used in small scale sewage (not exceeding 1 m³ per day), and if not output in septic sewage drain.Otherwise, it simply will not cope with its direct task of full cleaning before infiltration and sewage truck for evacuation have to call too often.

optimal solution - multi-chamber septic tank.An example is shown in the diagram:

Sewer drains through a pipe (. Item 1) enter the primary chamber (item 2.), Which in this case serves mainly to defend the liquid, its separation into lightheavy and insoluble fractions.It also collects the bulk of muddy sediment (Pos. 3).

In the overflow pipe (pos. 4) with lock system (water seal) partially past the original wastewater treatment fall into the second chamber (pos. 5).This compartment (often called methane tanks) for biological purification of water by the action of anaerobic bacteria.There is a chemical decomposition of organic components in the solid insoluble precipitate neutral (pos. 6), water and a gaseous component that goes into the vent pipe (pos. 10).This achieves a much higher degree of cleaning all domestic waste, including fecal material.

Further, the overflow conduit (pos. 7) held cleaning water moves or infiltration device (in this case shows a well, Pos. 8) with bombarded drainage layer (Pos. 9) or the third chamber septic tank, where thefinal clarification and fine defending.

often second or third camera is used for fine cleaning of aerobic microorganisms, which provides it with oxygen saturation - aeration, ie, periodic transmission of small air bubbles.To this end, a septic tank equipped with special compressors, aerators, which will require, however, summing up the power.

to equalize the pressure in the compartments of the septic tank, they are connected to the air channel (pos. 11).Be sure to provide for auditing and clearing the throat, closed hatches.

If a water treatment level increased requirements (eg, to allow its reuse for technical purposes, or if conditions are put forward the local sanitary-epidemiological service), the septic tank may be equipped with a biofilter and, with a special mineral or polymer filler.The biofilter can be one of the structural elements of the last septic tank chamber itself is such a final compartment, or be a separate module that is installed after the septic tank to the field of filtration or storage tank for treated water.

into the septic tank with biofilter achieved the highest degree of water purification of sewage, and such systems are almost can be classified as local treatment plants (VOCs).Naturally, the cost of such systems - is very high.

In terms of the individual construction of a septic tank is most often performed of reinforced concrete rings or constructed independently from the digging necessary capacities and cementing their walls.Both variants have a distinctive drawback - the difficulty in providing complete sealing septic chambers from the surrounding soil, the need to continuously monitor the state of the joints, places of passage of pipes, etc.

But now for sale a wide range of ready-made engineering solutions made of modern materials.Most often, this multi-chamber design, assembled in a single package, but can be and modular design.

distinguish between septic tanks in total volume, performance, size, material of manufacture, layout, and other parameters.All this is important when choosing a particular model.

Where permitted to place a septic tank?

Before purchasing a septic tank, you need to pre-determine the place of its future installation.Moreover, it is very often - quite impressive size design - the location of such treatment facilities must comply with certain rules prescribed statutory - SNIP 2.04.03-85, 2.04.02-84 and 2.04.01-85, SanPiN 2.1.5.980-00 and 2.2.1 / 2.1.1.1200-03.If desired, all of these documents are easy to find on the Internet.

• These requirements are not invented from scratch - any septic tank is an object of potential environmental or man-made threats, which can be as follows:
• Flooding of the soil and the foundation of buildings and structures due to violations of the tank itself leaks or pipe connections.
• Contamination of the site in the event of an overflow tank, for example, due to delayed evacuation of accumulated silt, or as a result of natural phenomena of nature - floods, abundant snowmelt, prolonged rains.
• penetration of liquid waste and transported them microbiological cultures in water sources or in closely spaced aquifers.
• penetration of odors in the residential areas.
• Poisoning organic topsoil, leading to plant death.

So, when choosing a site location of the septic tank adhere to the following standards:

• distance to the basement of an apartment house should be at least 5 meters, other outbuildings - not less than a meter.In exceptional cases, where applicable VOC gated with full biological waste treatment, the distance to a residential house may be reduced, but this issue requires additional coordination.
• The most important parameter is the remoteness of the septic tank from a water source.If it is well powered by the upper aquifer, the distance should be about 50, and sometimes, with light sandy soils - even 80 meters.Distance from the deep water well - at least 25 meters.If you allow the relief, the septic tank should be installed below the hill - so the probability of penetrating drains into aquifers will decrease significantly.

exact distance should be determined individually each time, based on studies of the soil and the existing relationship between aquifers and filtering its layers.

• Water pipes should not be held closer than 10 meters from the septic tank.
• minimum distance from a standing body of water (lakes, reservoirs, ponds) - 30 meters from the surface of the stream or river - 10 meters.
• If next to the house passes a line with heavy traffic, the minimum distance from her aged 5 meters.
• around the septic tank in a radius of 3 meters should be no trees or shrubs.First, the plant can get from the intoxication of saturation of the soil organic matter and die.Secondly, such a distance prevents the likelihood of damage to the capacity of the root system of trees or shrubs.
• There should be a minimum distance of 2 meters from the boundary of the neighboring plot.And while, of course, all the above mentioned standards must be met, regardless of the fact that the buildings, trees, water intake point and not your are behind a fence.Generally, of course, to avoid confusion in the future, the installation of a septic tank should be "amicably" to reconcile with neighbors.

As seen above requirements, to find the optimal location for the septic tank may not be so easy.It should also take into account the fact that for the regular pumping is necessary to provide road access to sewage truck.

If the optimal place is found, it does not mean that you can go directly to the installation of a septic tank.The device structures of this type necessarily require the drafting of which is coordinated at the local sanitary-epidemiological service.In drafting professionals should take into account all features of the site and the nature of the soil, to have accurately determine the required distances to other objects.

Construction should be carried out exactly according to the project - revealed later, "amateur" hosts will be considered as a serious administrative offense with all its consequences.

What volume of the septic tank is required

should define the stage select the septic tank - the definition of its scope in order to provide maximum cleaning sewage, complete decomposition of the organic components, and precludes the rapid overflow capacity.At the same time, must be respected and the reasonableness of the approach to the choice - too big septic tank will cost much more expensive, much more space is required, its installation will require major effort.

There are several methods for calculating the required capacity of the septic tank, but all is taken into account the time required for a complete process and upholding the primary decomposition of organic matter.For example, you can cause a sufficient "ponderous" formula:

W - the required amount of septic chambers for one person;

Q - average consumption flows, cubic meters per day;

t - the time required for clearing and settling of waste water (days);

With - concentration neosevshih suspensions at the outlet of the septic tank, mg / l .;

N - statutory rate drainage for each family member, l.per day;

T - average temperature of the waste water, ° C.

concentration of suspended matter in this is taken from the table, based on the average waste water temperature and average water consumption per person per day:

concentration is not settled sediment outlet, mg / l	average temperature sinks, ° C	required period of settling effluent (days) depending on the sanitation norms for 1 person (l. / day)
		50	100	150