• What can be cooked from squid: quick and tasty

    The impurities formed in the process of human activity must be removed from the premises. Problems with this do not arise in an area that provides for the equipment of a central sewerage system. If this is not possible, the owners country houses it is necessary to solve this issue by other available methods. Most often, the choice is made in favor of local treatment facilities, while it is necessary to decide what volume of septic tank is needed, what type of device to choose and how to maintain it. You will find answers to these and other questions in this article.

    What to consider when choosing a septic tank

    Life in the countryside today is chosen by many townspeople, while many are not ready for the difficulties that arise, and this, first of all, is the lack of communal infrastructure. It is necessary to solve the issues of water supply and waste disposal different methods, and it is important in this case to minimize the risk of sewage entering the soil and water bodies. According to the provisions of SNiP 2.04.03-85, the degree of purification of the liquid discharged into the reservoir must comply with the provisions of legislative acts regulating protection issues the environment... If the water purified in a septic tank is used again, sanitary and hygienic standards come into force.

    The main advantage of local wastewater treatment systems is the ability to maximize effective cleaning for the reuse of water for technical purposes, including for irrigation. When choosing a waste heat exchanger, the following factors should be taken into account:

    • the number of people living in the house;
    • frequency of residence;
    • features and composition of the soil;
    • terrain characteristics;
    • the level of occurrence of deep waters;
    • the depth of soil freezing.

    The local treatment plant is selected depending on the specific conditions and features of the area. It can be a storage tank that is sufficient to cope with sewage in a summer cottage intended for seasonal living, sedimentation tanks and full-fledged biological treatment plants. The latter guarantee almost one hundred percent purification of effluents and significantly reduce the frequency of use. special equipment... Therefore, when installing a septic tank, it is necessary to take into account the volume of the sewage machine, and the standard model is capable of accommodating 3.75 "cubes" of sewage. It remains to find out how to calculate the volume of a septic tank, taking into account the main factors.

    Calculation of the volume of a septic tank for a private house

    The main task of the septic tank is to utilize waste residues, so the device must have a capacity that allows it to accumulate and effectively purify the entire volume of sewage. In order to prevent the chambers from overflowing, it is necessary to correctly calculate the volume of a septic tank for a private house. It would seem that there is nothing difficult in this - you just need to add up the volume of all the chambers of the utilizer, but it would be too simple.

    In fact, it looks somewhat different: the volume of the first chamber is calculated from the level of the bottom to the overflow pipe, while the useful space of the second chamber is everything that is between the bottom and drain pipe... In addition, it should be borne in mind that over time, a large amount of solid particles accumulates in the first tank, which occupy a fifth useful space... Therefore, when calculating the liquid component, these 20% must be subtracted from the total volume. Now, in order to understand what a septic tank should be, it remains to compare the estimated amount of drains.

    According to the provisions of the Sanitary Norms and Rules (SNiP), the daily water consumption per average user is 200 liters, or 0.2 m3, but according to the rules, the minimum volume must be calculated with a margin of 3 days. Thus, for a family of 3 people, the approximate water consumption is 1.8 m3, and this is not counting the 20% that must be added to the bottom sediment.

    The refined formula for calculating the volume of a septic tank for a country house

    The sanitary standards indicate that the discharge of treated water outside the device should be carried out no more than once every two weeks. When making calculations, no one uses this provision, because in this case, for a family for 4 people, you need a device with a volume of 8 "cubes", at least. It is also not a fact that each tenant spends 200 liters of water per day, but experts do believe that one can proceed from an indicator of 0.1 m3 / day. In this case, a "cubic" septic tank will be needed for 3 people, but the installation of such devices is not encouraged.

    There are other exceptions to the rule in the form of an unexpected increase in the number of residents and expansion of the composition. household appliances(buying a dishwasher, for example). Therefore, it is necessary to calculate the required volume of a septic tank taking into account possible changes. Experts recommend using a more accurate formula:

    V septic tank = (Number of residents * 0.2 + 0.2) * 2

    To give a margin of safety, it is necessary to add the expense for one more conditional person, after which the result obtained is multiplied by two, counting on the fact that some residents are very fond of taking water procedures. Thus, for 5 people, for example, the minimum volume of a septic tank is 2.4 m3, ideal solution for 6 people there will be a waste heat exchanger with a capacity of 2.8 m3. As practice shows, these are real numbers that allow you to accurately buy a septic tank, which will make living in the house as comfortable as possible. There is another formula that takes into account the consumption of all used devices and devices, presented in the table:

    The calculations are based on the consumption of 150 liters per day per person and take place in several stages. On the first, the average consumption per person is calculated, taking into account the fact that he will use the shower for 7 minutes a day (flow rate 10 l / min), a bidet for 5 minutes (flow rate 8 l / min) and a bathtub, which takes 110 liters of water. Based on this, the average consumption per person, excluding household appliances, is 150 liters (average) + 10 * 7 + 8 * 5 + 110 = 370 liters / day. To obtain the required volume of the septic tank, it remains to multiply this figure by the number of residents.

    It is even easier to calculate the required volume of a septic tank for a summer residence intended for periodic residence. In this case, less-functional drives are most often installed, which must be selected, taking into account how many cubes can be disposed of at a time by the sewage equipment.

    The required volume of a septic tank for a bath

    Today we hear more and more often about healthy way life, so even in the country you can find a Russian bath or sauna. Their presence significantly increases water consumption. In order for the local sewage system to work effectively, the volume of the septic tank for the bath will have to be added to the calculated indicators. In this case, it is better to use not storage devices, but two-chamber septic tanks or biological treatment plants. The minimum consumption in the bath is 100 liters of water per day, so the capacity of the device must be increased by 300 liters per day. Most often chosen for a bath plastic septic tanks, although many people prefer durable concrete ring devices.

    Why choose septic tanks of the Septic Topas Plus company

    In Moscow and the Moscow region, many companies offer services for the sale and installation of septic tanks, but this difficult question must be entrusted to the best. It is not difficult to imagine the consequences of installing a low-quality device. The Septic Topas Plus catalog contains only proven septic tanks of domestic manufacturers: Topas, Unilos Astra, Eurolos, Termit, Tver, Diamant, Dochista, Terra, Biozon and Kolovesi. The company's managers will go to the site free of charge, and after preliminary calculations, they will help you choose the most suitable utilizer. As a confirmation of the quality of services, we offer a three-year warranty, affordable prices and discounts for regular customers.

    How to calculate the dimensions correctly

    Such a concept as size can be applied to such data as:

    • Length;
    • Width;
    • Height.

    This is important in order to make the correct foundation pit, you need to make a septic tank calculation along with all its additional details. And in order to find out the volume of wastewater per day, you need to look at the size of the body and tanks

    If this is a one-piece structure, then you can estimate the size of the equipment according to the technical data on the package and compare them with the dimensions of your summer cottage or private premises.

    Norms and rules when designing a septic tank installation for a summer residence:

    • If you have a small area, then perhaps the calculations of another apparatus will come in handy;
    • To make the correct calculations, you can use the tables of engineers;
    • The minimum working depth should be 1.3 m and the width less than 1 m;
    • The depth from surface to bottom should be no more than 3.2 m.

    Calculation of the volume of a septic tank

    How many ways are there to calculate volume? We will find out about this now

    After all, it is very important to buy optimal septic tanks, the calculation of which is the main criterion for their acquisition

    There is a standard formula for calculating the volume of a septic tank:

    Now let's write down all the components of the formula:

    W
    - Calculation of the required dimensions of the sump in cubic meters x (m3); t
    - Time spent on processing or storing sludge (days); C
    - The number of suspended particles in ml per 1 liter (mg / l); N
    – Daily rate person (l / day); T
    - Drain temperature (˚С); Q
    - Water consumption in cubic meters per day (m3 / day).

    According to this formula, we calculate the unit we need.

    As for the temperature of the drains in the sewage system, it must be remembered that it will not be the same as in the room. This largely depends on the plumbing fixtures that are used in enterprises. But there is accepted norms, for example, in winter - 10 ˚С, and in summer - 15-20 ˚С. This greatly simplifies the calculation of the formula.

    There are many different tables that can be prepared with data produced by engineers. Basically, these are averages.

    If we take data from the table, then the calculation should look like this:

    W = K x Q,

    K - estimated settling time Wastewater(table);

    Q
    - the amount of drains per day.

    There is also a more simplified version of determining how much the device will have to hold. It is necessary to multiply the number of people by 200 liters (daily rate for 1 person) and 3 days (time for processing waste waste) and divide the resulting amount by a thousand - this should be a calculated volume (in cubic meters).

    Average statistics show that the daily rate per person is 200 liters of water. For unforeseen expenses, the same amount of water is usually added. And then for a two-tank septic tank, which defends water for 2 days, the formula looks like this:

    (N x 200 + 200) x 2

    N - The number of people who live in the house.

    Simplified calculation of a septic tank by the daily volume of waste

    The liquid part of the effluent is retained in the septic tank for 3-5 days, after which the clarified water leaves the working chambers, overflowing into filtration fields or absorption wells. The solid insoluble fraction will remain at the bottom of the settler until the next pumping of the bottom sludge. Degradable waste is transformed into water and gas in six months.

    Therefore, the most in a convenient way determining the total volume of a septic tank is the simplest tripling of daily effluents, which can be determined either in a natural way - according to the average readings of the "meter" of water consumption.

    However, the specified method for calculating a septic tank is effective only if the volume of daily waste does not exceed 5 cubic meters.

    Calculation of the volume of a septic tank by the number of users

    Obtaining data on the average daily volume of wastewater without the ability to use the sewer network, which does not work for sprouting without a septic tank, is an almost insoluble task.

    Therefore, instead of a full-scale determination of the volume of daily waste by the meter, most home-grown designers use the calculation method according to sanitary standards water consumption.

    These standards assume that the maximum daily water consumption per person ranges from 125 to 350 liters. That is, a family of 2 people consumes from 250 to 700 liters of water per day. And the volume of wastewater in the sewage system serving a family of 4 reaches up to 500-1400 liters per day.

    As a result, using the method of tripling the daily volume of effluents, we get the following result:

    • The volume of a septic tank serving 1-2 users is 0.75-2.1 m3.
    • The volume of a septic tank serving 3-4 users is 1.5-4.2 m3.

    However, according to professional designers engineering systems, this method of calculating the volume is far from ideal. Indeed, in this case, we do not take into account either the mass of insoluble sediments, or the volume of bottom silt, or other important factors.

    Engineering calculation according to the formula for the optimal volume of the settling tank

    An accurate determination of the volume of a septic tank is possible only by the following formula:

    In this case, Q - the daily volume of wastewater - is determined according to sanitary standards and the number of users,

    С - concentration of suspended solids in wastewater - determined according to the table,

    N - the sanitary norm of water supply for one user - is taken from SNiP.

    The shelf life of precipitation - t - is determined according to the tables of natural decay, and the temperature of the effluent - T - is taken equal to 10-12 degrees Celsius.

    However, this method of calculating the volume of a septic tank is justified only in the case of designing the sewer network of a cottage village or apartment building... At the household level, assuming the possibility of errors in calculations, such accuracy can be neglected, since deviations at the level of ± 0.5-1 cubic meters will not significantly damage either the efficiency of the system or the wallet of the home owner.

    Features of the device of multi-chamber septic tanks

    The above methods for calculating a septic tank relate to the total volume of the septic tank. Meanwhile, modern sedimentation tanks have at least two chambers. A more or less effective scheme involves dividing the internal volume into three chambers - primary, (gravitational), secondary (aerobic) and a fine cleaning zone, on top of which an aerator with a biological load is also mounted.

    Installation diagram of a three-chamber septic tank

    In this case, the primary chamber of gravitational wastewater treatment should occupy at least 50 percent of the total volume of the septic tank. The secondary sedimentation tank and the wastewater treatment chamber each occupy 25 percent of the total volume. The aeration zone is mounted in a separate module installed over the septic tank.

    The volume of a two-chamber septic tank is divided by a ratio of 3: 1 - the primary gravitational cleaning chamber occupies 75 percent of the total volume, and the aerobic fermentation zone - only 25 percent.

    As a result, in a three-chamber septic tank with a volume of 4.2 m A two-chamber septic tank of the same volume will be divided into two zones: a gravity chamber with a volume of up to 3.15 m3 and an aerobic chamber with a volume of up to 1.05 cubic meters.

    Choice of pipes

    Sewer pipe diameters

    During the laying of the sewage system of a private house, waterways are used round section with an inner diameter from 40 to 110 mm made of polyvinyl chloride, resistant to aggressive environment waste water. Since various plumbing and household appliances are characterized by an unequal volume of wastewater, differing in consistency and composition, pipes with the following internal diameters are used:

    • sinks, kitchen sinks - 40-50 mm;
    • baths, shower trays - 50 mm;
    • washing machines and dishwashers - 50 mm;
    • urinals, bidets - 50 mm;
    • toilets - 110 mm.

    If a private residential building has 2 or more floors, the upper bathrooms are connected to the sewerage system of the lower ones using vertically arranged communications - risers - with an inner diameter of 110 mm.

    Example calculation of a septic tank for a family of 4 people

    For example, you can consider the option of calculating a septic tank for servicing a house where 4 people live permanently.

    0.8 x t x (100% - 30% / 100%) x 120% = 0.8 x t x 0.7 x 1.2 = t x 0.672 sec.

    0.8 - consumption of solid residue of processed wastewater, calculated for one person; t - time of decomposition of solid residues in days; 100% - total sludge volume; 30% - percentage of natural sludge decay; 120% - 100% total sludge volume + 20% sludge residues after the previous cleaning of the septic tank.

    To get a closer look at the calculations of water consumption per person per day, you must first determine the amount of plumbing equipment use, as well as the frequency of use of plumbing equipment in the house.

    Photo: number of use of plumbing equipment

    Let's take for calculations for one person the minimum water consumption - 150 l / day.

    So, for example, on average, the use and consumption of water by one person can make up the following picture:

    • one minute of taking a shower will consume about 10 liters of water;
    • taking a shower or bath on average takes about 7-15 minutes;
    • when using a bidet or toilet, water consumption is about 8 liters;
    • using the bidet takes an average of 5 minutes;
    • one taking a bath or jacuzzi has to consume water in the amount of 110 liters;
    • Washer with a load of 2 kg of linen, it consumes water in the amount of 70 liters per one strip;
    • Dishwasher in one cycle of its work spends water in the amount of 15 liters.

    (150 + 10 x 7 + 8 x 5 + 110) = 370 l / day.

    Thus, with a minimum indicator daily consumption water by one person, we reached the maximum daily water consumption by one person - 370 l / day.

    Both indicators, minimum and maximum, are specified in SNiP 2.04.09-85, which indicates the correctness of the calculations.

    Now let's calculate the total consumption (Q) when consuming water, including a washing machine and a dishwasher, for 4 people permanently living in the house:

    Q = 370 x 4 + 70 + 15 = 1565 = 1.6 cubes per day

    Given the previous formula for calculating the volume of a septic tank - 3 x Q, we can now calculate the volume of a septic tank to serve a family of 4 people:

    3 x 1.6 = 4.8 m3

    4.8 m3 in this situation is the most optimal indicator for calculating the volume and size of a septic tank. If it is necessary to take into account the minimum indicator of the size of the septic tank, then you can use the following calculations:

    4.8 x (1-0.2) = 3.84 m3

    This must be done in cases where it is necessary to reduce the size of the septic tank to its minimum use with the number of 4 permanent residents.

    The formula for calculating the reduction uses only the permissible rate of waste treatment, less by 20%, it is not possible to reduce more.

    If this assumption is violated, an emergency flooding of the septic tank, poisoning of the soil and the environment, and, as a result, the imposition of high fines by government agencies can occur. Who will have every right to do so.

    To calculate the required depth for the construction of a septic tank, which will have to serve a family of 4 people, you can use the following standard calculations:

    4.8 / 1 / 1.8 - 2.6 meters, where

    4.8 - cubic meters of septic tank volume; 1 - meter of septic tank width; 1.8 - meters along the length of the septic tank.

    Such a measure may be necessary if your personal plot is limited in area, and you cannot give a lot of land for building a septic tank.

    In some regions of Russia, the depth of soil freezing is about 2 meters or more.

    Any violation or deviation from the norms and rules adopted in the state documentation of SNiP leads, as a rule, to a complete stop of the operation of one or another septic tank, as well as to the imposition and payment of large penalties provided for by the legislation of the Russian Federation.

    Important! Therefore, before the construction or installation of finished treatment equipment, it is necessary to clearly track all the rules and regulations for the construction of autonomous sewers, which can be found, first of all, in SNiP 2.04.03-85 “Sewerage. External networks and structures "and other regulatory documents

    It is also necessary to do a number of correct and accurate calculations for the volume of water consumption, the volume of the septic tank, its design and installation parameters.

    External networks and structures "and other regulatory documents. It is also necessary to do a number of correct and accurate calculations for the volume of water consumption, the volume of the septic tank, its design and installation parameters.

    Calculation of dimensions and volume

    To accurately determine the internal space of the tank, a specially developed formula for calculating the volume of the septic tank is used. But it implies a large number of complex meanings and is difficult for a particular practical application... In practice, the volume of a septic tank for a private house is calculated using a simpler formula. Number of people X 200 liters of sewage rate per person X 3 days (waste processing time) / 1000 = volume in cubic meters.

    To serve 4 people, a septic tank with a volume of 2.4 cubic meters is required.

    Consider an option with the calculation of the volume for this number of family members.

    When calculating the parameter "number of people" it is better to take "with a margin" in order to take into account the load when visiting guests and other unforeseen situations. The daily rate can be increased if there are small children and pets. This indicator also increases if you use a large number of different household appliances with water consumption (washing machine).

    As already mentioned above, there are laboratory calculations that are given for factory septic tanks. Based on these data, it is possible to carry out calculations in situations with containers made by yourself.

    So, with a septic tank in three sections:

    • for two people, a useful volume of 1.5 cubic meters is required. m .;
    • for three or four people - 2 cubic meters. m .;
    • for five or six people - 3 cubic meters. m .;
    • for eight people - 4 cubic meters. m .;
    • for ten people - 5 cubic meters. m .;
    • for twenty people - 10 cubic meters. m.

    The main building material when arranging a septic tank, concrete rings are independently. And the key calculation is to determine the amount of these materials. Most often, 3 reinforced concrete rings with a diameter of 1.5 m and a height of 0.9 m are enough. More than 5 rings are not used per septic tank.

    Do not forget about other elements when self-arrangement systems. These include:

    1. Reinforced concrete plate.
    2. Ventilation pipe.
    3. Cement, sand, crushed stone.

    When calculating the required volume of a septic tank, the formulas given above are used. In addition, it is necessary to know the volume of one ring in order to determine the sufficient number of rings in the container.

    V = ∏R2H = ∏ (d2 / 4) H, where:

    • V is the volume of the cylinder;
    • ∏ - number Pi (3.14);
    • R is the radius of the base;
    • d - base diameter;
    • H is the height.

    Knowing the volume of the ring, it can be compared with the obtained figures for the required volume of a concrete septic tank. The volume of 1 ring (d = 1.5 m; H = 0.9 m) is approximately 1.6 cubic meters. m. It turns out that for 4 family members in a house with all amenities (hot water, etc.), 2 rings will be needed to equip a septic tank.

    This amount will be enough for 5 people. Up to 10 people can be provided with one container of 3 rings. If you plan to live from 10 to 20 people, you will need to equip a septic tank, consisting of several containers, since more than 3 rings cannot be installed. In this case, it is better to take care of purchasing a factory model of sufficient volume.

    What is included in the calculation

    The tasks of calculating the required volume and parameters of a particular septic tank fall on not only determining and finding the volumes, sizes of chambers, but also identifying the amount of building materials, necessary tools or installation techniques.

    Therefore, in order to know exactly what parameters it is necessary to acquire or build a septic tank, what building materials may be needed at the same time, and how much they are needed, the following important details should be correctly calculated:

    • dimensions of the body and containers of the factory septic tank;
    • daily volumes of wastewater that the septic tank chambers can receive and process;
    • calculations of the volume of water used per day, which falls on each permanently residing person in the house;
    • calculations of the amount of building materials for the installation and construction of a septic tank with your own hands.

    To ensure sanitation and cleanliness ecological environment any options for septic tanks, both factory and home-made, should be installed after you already know exactly the parameters, dimensions of the chambers and its operational capabilities.

    Important! And, of course, this must be done long before you decide to buy a ready-made septic tank from one manufacturer or another, and you will also prepare building materials for the construction of a septic tank with your own hands.

    You should take into account not only the number of people permanently or seasonally residing, but also your income, i.e. the funds that you have to equip your sewer system with one or another type of septic tank

    If you need to install a septic tank for permanent residence v country house, then, of course, it is best to purchase a factory septic tank from a manufacturer that has proven itself in the production of high-quality sewage treatment equipment.

    Autonomous sewerage in a private house is a complex system, the device of which is a complex technical task. The sewerage equipment market is represented by many options, among which three-section septic tanks made of reinforced concrete or plastic are especially popular.

    Before buying a septic tank, it is necessary to make an accurate calculation of the useful volume of the future tank. The volume of the septic tank is calculated based on three times the daily water consumption by one person. If you neglect the calculations, then over time, the sewage system can malfunction, which will lead to unpleasant consequences or to an environmental problem.

    For the calculation, you can use the average value of water consumption by one person - 200 liters per day. Or you can follow the meter readings in the house. Using the meter readings, it will be necessary to make an amendment to the calculated mass of water. This is the so-called reduction factor, which is 0.6-0.8. If the house has a washing machine or dishwasher, then the coefficient will increase, which is 1.5-2.

    The table shows the approximate volume of the septic tank. The values ​​can change according to the reduction or increase factors.

    Number of peopleWastewater consumption, m3 / dayseptic tank volume, m3
    3 0,6 1,5
    4 0,8 1,9
    5 1,0 2,4
    6 1,2 2,9
    7 1,4 3,4
    8 1,6 3,9
    9 1,8 4,4
    10 2,0 4,8

    According to sanitary standards, sewage drains must be settled for at least three days, so the estimated volume of a septic tank per person will be 0.6 cubic meters. - 0.2 (200 liters per day) multiplied by 3. Accordingly, for a family of three, the volume of the septic tank will be 1.8 cubic meters. the calculation of the volume of the septic tank implies the calculation of the working volume, on which the number of chambers does not depend.

    Two-chamber septic tanks will cope with their task as well as a three-chamber tank. If the septic tank has two chambers, then the volume of the main one should be at least 0.75 of the main volume. If the septic tank is three-chamber, the volume of the main chamber should be at least 0.5 of the total, the other two are 0.25 of the main volume.

    • When choosing equipment, it is important to consider its performance;
    • Volley discharge of effluents within two hours;
    • An important parameter is the insertion depth. sewer pipe, which indicates the depth of the pipe;
    • It is worth paying attention to the service indicator, which indicates the frequency of removing sludge from the bottom of the septic tank;
    • An important indicator when choosing equipment is the depth of sewage waste treatment. Biological purification septic tanks guarantee 98% purification;
    • Also, when choosing a septic tank, you should pay attention to the material. Making the right choices can make your equipment easier to maintain. A septic tank is selected according to what type of soil lies on the site;
    • An important factor in the convenience of equipment maintenance is the possibility of self-service;
    • The reliability of the equipment depends on its complexity;

    It is not always advisable to save on equipment, since sewage drains contain a huge amount of "heavy" elements that are not always processed by bacteria. In this connection, the septic tank must have a certain volume reserve so that the non-recyclable elements have time to settle to the bottom, which will soon be pumped out by a sewage machine.

    Consider the approximate parameters of the norms of water consumption by one person per day:

    • 40 cubic meters - shower (7-10 min);
    • 8 liters - bidet, toilet;
    • 100 liters - bath;
    • 80 liters - washing machine;
    • 15 liters - dishwasher;

    An example of calculating the volume for 3 people

    To do this, we need a formula for the total volume:

    • V - working volume (cubic meters);
    • n is the number of people;
    • Q - water consumption by one person (l / day);
    • 3 - time of sewage treatment (days);

    3 * 200 * 3/1000 = 1.8 cubic meters. According to calculations, a septic tank with a total volume of 1.8 cubic meters will need to be installed for three people. - two-chamber reservoir.

    Calculation of a septic tank for 4 people

    Let us consider in more detail the method of calculating the volume of a septic tank, where we independently estimate the amount of water consumed by one person (Q). As a rule, in the summer, each person takes a shower in the morning, in the evening, for example, takes a bath:

    200+ (10 * 7) + 100 = 370 liters per day.

    4 * 370 * 3/1000 = 4.44 cubic meters. According to calculations, for a private house for 4 people, a septic tank with a volume of 4.5 cubic meters will need to be installed - a two-chamber or three-chamber septic tank.

    Calculation of a septic tank for 6 people

    According to the above values ​​of the volume of the septic tank by the number of people, it can be assumed that a tank of 3 cubic meters will be enough for 6 people. For an individual calculation of six people, we apply the formula and compare the data with the average values ​​indicated in the table above. Let's say that each person takes a shower for 10 minutes and wash 2 kg of clothes.

    200+ (10 * 10) + 80 = 380 liters.

    6 * 380 * 3/380 = 6.84 cubic meters.

    The result obtained is much higher than the average values ​​in the table. In any case, it is necessary to make a calculation in order to avoid incorrect operation of the septic tank. Also, when calculating, it should be borne in mind that guests may come to the owners of the house, which will increase the load on the sewer system.

    Before starting the construction of the sewerage system, you must familiarize yourself with the rules and regulations for the device of autonomous sewerage systems (SNiP 2.04.03-85) "Sewerage". Deviation from the rules and regulations, as a rule, leads to equipment failure, which in turn can cause an environmental problem. In this case, the legislation of the Russian Federation provides for the imposition of penalties on the owner of a private house.

    To avoid unpleasant consequences as a result of a violation of the installation technology and the calculation of the volume of the septic tank, it is necessary to consult with specialists. The company "Moskomplekt" has many years of experience in installing septic tanks for a private house, summer cottages, etc.

    See for yourself, call and we will answer any questions you may have. It is possible to mount the sewage system on your own, but in any case, it is better to consult with a specialist before starting work. Call and our experts will answer all your questions.

    Well, the last article in the topic on calculating the size of a septic tank is about how to calculate the volume of a septic tank.

    At the same time, we will touch on the calculation of sizes drain pit- maybe it will come in handy for someone.

    And since this article is the last, we will draw final conclusions about the choice of the size of septic tanks.

    The number of chambers and the design of the septic tank

    A septic tank is a container with a number of chambers from one to three. The chambers are interconnected by means of pipes for the possibility of the passage of wastewater from one chamber to another and so on to the extreme filtering chamber:

    Water from the outer chamber can go into the soil through pipes or directly through unsealed walls and the bottom ... although this is not welcome, but these drains need to be cleaned up, which, however, I already wrote about in the very first article about septic tanks. Then why am I repeating here about the design and what does the size of the septic tank have to do with it, you ask the question? To refresh your memory - this will come in handy, starting with the next line ...

    How to calculate the volume of a septic tank?

    The volume of a septic tank does not mean the entire volume of the container, but only its working volume.

    What is the working volume of a septic tank?

    Let's look at the diagram (clickable):


    The outlet from the septic tank is 3-5 centimeters below the inlet. Therefore, the volume of a septic tank is considered only a working one - one that can be filled with drains, from the outlet level to the bottom.

    Calculation of the volume of a septic tank by the number of drains

    Well, now the actual calculation of the volume of the septic tank.

    To calculate the volume of a septic tank, you need to take into account the average daily volume of waste. Because the water should not just flow through the septic tank without stopping, but should stay inside for some time so that the solid particles have time to settle. In addition, the processes of decomposition of these particles also take time. Therefore, the waste water in the septic tank should be at least two days. But ideally - up to ten days! I suppose it's clear: the longer the drains stay inside the septic tank, the better they will be cleaned (settled).

    From these considerations, we calculate the volume of the septic tank.

    It is written in SNiP: “the full estimated volume of the septic tank should be taken: at a wastewater flow rate of up to 5 m3 / day. - at least 3-fold daily inflow, with a flow rate of more than 5 m3 / day. - not less than 2.5 times "(p. 6. 79.).

    Again. Let's say we figured out that the volume of wastewater from our house will be about 5 m3 per day. This means that the minimum volume of our septic tank should be 15 m3. More is possible, less is not. When the volume of wastewater is more than 5 m3, we multiply our "estimated" value by 2.5 and we also get a value less than which the volume of the septic tank should not be done, but more - as much as you like.

    By the way, with such calculations, at least once a year, the septic tank will need to be pumped out.

    The volume of the septic tank and the number of chambers

    Except what has been said. Septic tanks can be made with one, two or three chambers.

    The volume of these chambers is also regulated by SNiP:

    “Depending on the wastewater consumption, you should take:

    single-chamber septic tanks - with a wastewater flow rate of up to 1 m3 / day,

    two-chamber - up to 10 m3 / day,

    three-chamber - over 10 m3 / day.

    The volume of the first chamber should be taken: in two-chamber septic tanks - 0.75, in three-chamber septic tanks - 0.5 of the estimated volume of wastewater. In this case, the volume of the second and third chambers should be taken at 0.25 of the calculated volume. In septic tanks made of concrete rings, all chambers should be of equal volume. "

    In my opinion, everything in SNiP is written quite transparently, there is nothing to comment on.

    Calculation of the volume of the septic tank according to the formula

    Septic tank volume = (Number of people living in the house x Water consumption rate per day per person x Number of days for which the septic tank purifies water) / 1000

    So, the conditions of the problem:

    A family of 4 lives in the house,

    The daily rate of water consumption per person is 200 liters,

    The drains in the septic tank must be allowed to settle for at least 2 days.

    We substitute the data into the formula and calculate:

    Septic tank volume = (4 x 200 x 2) / 1000 = 1.6 m3.

    Let me remind you: we considered the WORKING VOLUME of the septic tank, and not the full volume of the container.

    But do not rush to grab a shovel and dig, please read the article, there is something else, from which you need to proceed when calculating the volume of a septic tank. Namely: the volume of the sewer tank.

    How to calculate the dimensions of the drain pit?

    The depth of the drain pit can be determined in the same way as the depth of the septic tank. But, since there are no requirements for hydraulics, the shape of the drain pit does not really matter anymore (let me remind you that water flows through the septic tank, but it just "waits" in the drain pit). How irrelevant is the ratio of the length and width of the pit.

    The volume here is also calculated from the average daily water consumption.

    You can apply this formula:

    Vpits - the volume of the drainage pit,

    Ndays - the estimated number of days after which the pit is pumped out (for some reason, it is recommended to do this at least twice a month, that is, every 15 days, I don’t know why, maybe so that the sewers do not lose the habit of working? :)),

    N people - the number of people permanently living in the house,

    V1 is the estimated volume of water per day per person (it is believed that this is ~ 150 liters).

    For example, if a family of 4 constantly lives in the house, then:

    Vpits = 15 * 4 * 150 = 9000 liters = 9 m3

    Arrangement of an absorbing drainage pit allows wastewater to be discharged directly into the soil. This is possible with small (in my opinion, less than one cubic meter) volumes, since it is not capable of causing significant harm to the environment.

    The volume of the septic tank and the volume of the sewer tanks

    In the example calculations above, of course, the values ​​are averaged.

    It is better to increase the settling time of effluents in septic tanks.

    The volume of the septic tank and the drain pit can be adjusted to the volume of the cistern of the sewage machine, which will pump out waste water. It is not recommended to make a septic tank less than 3 m3 (the cistern of a sewage machine has about the same volume, a little more: 3.2 cubic meters). If the septic tank is significantly smaller, then it turns out that you pay both for full car, in fact, it will take out only a part of its possible volume.

    There are cars with a five-cube tank; if they are in your area, then you can orient the volume of the septic tank to them, check this where you live.

    General conclusion about the calculations of the size of septic tanks

    So, in order to determine the size of the septic tank, you need to correlate the following: the required working depth of the septic tank, surface area (length x width), the minimum and maximum allowable dimensions, as well as the capabilities of the sewage machine (if, of course, the septic tank will be pumped out by it). And then we move on to the choice of materials; read about the pros and cons of each material and the construction technology from them in the following articles.

    Suburban settlements are rarely provided with centralized wastewater collection and treatment systems. Few of today's residents live with "amenities" in the yard. An excellent way out of this situation is arrangement local sewerage system... To do this, you can use a ready-made container for a septic tank. Choosing this option, the work on the construction of the sewage system will be completed much faster than during the construction of containers from brickwork or reinforced concrete.

    Types of containers

    To date, it is quite easy to find a container for a septic tank on sale. There is various options: from ordinary plastic tanks installed as storage tanks to complex and multi-chamber stations equipped with pumps or compressors, which are used for high-quality wastewater treatment.

    What to choose depends on the consumer and on some factors:

    • The nature and properties of the soil on the site. When choosing a container for a septic tank, you should take into account the characteristics of the soil and the levels of the location of groundwater. For example, the arrangement of filtration fields on clayey soils is irrational, such construction will take a lot of money and labor.
    • The volume of drains in the house and the frequency of using the sewage system. If the house is used as a summer residence, that is, for living in it on weekends or holidays, then you can choose a simpler drive. When the structure is planned to be used continuously for permanent residence, then in such cases the housing is equipped with a full set of sewage equipment. In this case, it is worth purchasing a large container for a septic tank.

    V modern construction several methods of arranging installations for local sewerage systems are used:

    • Septic tank- the simplest option. It is the safest analogue of a cesspool. Environmental friendliness is ensured by the tightness of such a container for a septic tank, it does not allow contaminated wastewater to enter the soil and violate the safety of the soil.
    • Installation of local cleaning systems. This is a modern equipment in which a multistage purification of sewage streams is carried out. At the output of these systems, almost pure water is obtained, which can be discharged into reservoirs even without additional purification.
    • Conventional septic tanks... Installation of septic tanks that use mechanical or biological treatment drains is a good option. Such systems are supplemented with filter wells or filtration fields.

    This is one of the most simple options arrangement local sewerage... All the outflowing water enters the septic tank. Cleaning of this tank is carried out by special machines (sewers). It should be borne in mind that the larger the volume, the less you will have to use sewers.

    The volume of this type of septic tank is chosen, taking into account the estimated amount of drains. It is profitable to acquire container volume for a septic tank, which will be equal to the volume of the tank of a sewer truck.

    Septic tanks not only collect wastewater, but also purify it in a certain way. This system includes a septic tank, which serves to settle the effluent. The incoming waste is distributed throughout the chamber, solid components fall to the bottom, light fractions rise upward, and partially purified water passes into the next compartment of the tank, in which further water purification is carried out by filtration or the use of bacteria. Further - the water is cleaned up in the soil itself.

    Any owner country house wants to make his stay in it more convenient and comfortable. At the moment, modern construction of summer cottages and cottages mainly provides for the organization of autonomous water supply and sewerage.

    Very often, outside the territory of the city, there is no provision for engineering communications. This mainly concerns the sewerage system. In view of this, those who became the proud owner of a country house begin to build autonomous sewerage system... In this case, it means the organization and installation of treatment facilities, which are called septic tanks. The construction of septic tanks can be performed using expanded clay concrete blocks, plastic containers, metal structures, reinforced concrete rings and everything else.

    Often, septic tanks are a structure that consists of several chambers, which can be either concrete rings or ready-made devices. In some cases, the owners of a country house get by with simple digging of a hole and the construction of formwork around its entire perimeter.

    A container for a septic tank, which would meet all the requirements for arranging sewage systems, can be made independently. To do this, you just need to weld a metal tank of the required volume. In such a container, it is necessary to provide several sections, which will be separated by partitions for the primary purification of effluents. In the manufacture of a container for a septic tank with your own hands, there are a lot of options for creativity, your ideas may be limited only by the regulatory requirements developed for this type of containers.

    When self-building a container for a septic tank, it must be borne in mind that such equipment will subsequently be placed underground. Because of this, such a structure must be strong enough and have special protective ribs that protect the septic tank from destruction during soil movements. This system must also be protected against corrosive processes.

    The capacity for the septic tank must be supplied technological hatches for preventive maintenance during operation. You also need to provide it with holes for pumping fluids or for periodically cleaning the bottom from silting. A cesspool can also be used for this, but such a solution may turn out to be enough bad consequences... Excess ground water can raise the level of the cesspool itself, and gases released during the decomposition of elements can enter the house through sewer pipes.

    At the dacha, it is better to use septic tanks to create an autonomous system for treating wastewater and sewage waste.

    Today there are a lot of companies producing containers for septic tanks.

    They are made from:

    A wide range of different tanks are produced, which are manufactured in volumes from 300 liters to 10 thousand liters... Such containers are used in production for the collection and purification of process waters, as well as for their high-quality disposal. Properties various materials, which go to the production of these septic tanks, allow them to be used in different climatic conditions for the arrangement of autonomous sewage systems.

    For the improvement of summer cottages or country houses, you can buy a septic tank made in an industrial environment. The cost of such containers depends on many factors. Before you buy a container for a septic tank, you should carefully calculate the required volume. In this case, it is necessary to take into account the number of residents with a certain margin. The use of professionally made septic tanks in the sewerage systems of private houses or cottages can solve many problems. This option is the most acceptable in terms of time costs and is much more environmentally friendly than an ordinary one. cesspool.

    During the construction of septic tanks, it is necessary to comply with all standards for their location from residential buildings, as well as from wells or open reservoirs. When preparing a pit for this treatment complex, one should also take into account the depth of soil freezing and increase the size of the pit, taking into account this parameter. A container for a septic tank made of plastic materials will serve excellently for many decades, it will be possible to add various additives to it to accelerate the processing of wastewater by microbes. This factor should also be taken into account when arranging a place for a treatment system.

    In order for the septic tank to fully satisfy the needs of all people living in the house, it will be necessary to carry out the correct calculations of its required volume. Despite the fact that it must contain a sufficient amount of wastewater, it is desirable that it occupy as much as possible less space and was compact.

    You can give approximate calculations of the required volume of a septic tank depending on the number of people living in a country house:

    • up to three people - the volume of the septic tank is 1.3 cubic meters;
    • from three to five people - 2.5 cubic meters;
    • from six to ten people - 10 cubic meters.

    These estimates are approximate and may vary due to certain factors.

    One of these factors will be. In this case, the amount of water consumed will decrease somewhat, since the owner of the house will try to save on its consumption. In view of this, it is safe to say that it will take a small amount to choose the volume of a septic tank.

    If the house is inhabited by those who quite often take a shower, a bath or use other plumbing fixtures, then the approximate figure of the required volume should be increased by one and a half times. As statistics show, the usual a person uses about 200 liters of water every day and to this figure it is necessary to add the same amount for various contingencies.

    Septic tank calculation formula

    In modern construction, where the installation of a two-chamber septic tank is required, there is a special formula according to which the required volume is calculated sewage treatment plant:

    B = (H * 0.2 + 0.2) * 2

    B - the required volume of the septic tank, H - the number of residents in the house.

    In addition, experts advise to be more far-sighted and take into account the possible increase in the number of people who will live in the house. Therefore, it is advisable to build a septic tank with a volume for a few more people, except for all family members who live in the house at the moment.

    Undoubtedly, it is very important to correctly determine the volume of the septic tank, but do not forget about its shape. The main factor that affects the shape of the treatment plant is the level of soil freezing depth. Therefore, the depth of the septic tank should not exceed three meters.

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