Farmers need fuel for heating systems, electricity generation and other daily needs. With energy prices rising steadily year after year, every homeowner or small business owner has at least once thought about how to produce biogas at home.

Biogas plants are increasingly being used on farms, saving money on heating

A biogas plant for a private house allows you to organize the production of biogas right in your yard, which solves the problem of fuel. Since a significant percentage of villagers have skills in working with welding and metalwork tools, the issue of self-manufacturing a gas production unit looks logical. So you can save not only on work, but also on materials, if you use improvised means.

What is biogas and how is it produced: production and production

Biogas is a substance produced during the fermentation of organic waste that contains enough methane to be used as a fuel. When burned, biogas releases heat, which is enough to heat a house or refuel a car. An energy source is manure, which is readily available and cheap or completely free, if we are talking about a livestock enterprise or a large private farm.

Biogas is an environmentally friendly biofuel that you can produce with your own hands, biological gas is related to natural gas. The gas is obtained as a result of the processing of waste by anaerobic bacteria. Fermentation takes place in the airless space of a container called a bioreactor. The rate of biogas production depends on the amount of waste loaded into the biogenerator. Under the action of bacteria, a mixture of methane and carbon dioxide with some impurities of other gaseous substances is released from the raw material. The resulting gas is removed from the bioreactor, purified and used for own needs. The processed raw materials at the end of the process become fertilizer, which is used to improve soil fertility. Obtaining biogas is beneficial for livestock enterprises, which have access to free manure and other organic waste.

Advantages of burning fuel from manure (fertilizer on the farm) for heating: electricity from methane

The advantages of biogas as a fuel include:

• Efficient and environmentally friendly recycling
• Availability of feedstock for gas production in rural areas
• Possibility to organize a closed cycle of non-waste production of gas and fertilizers from manure
• Non-depleting self-replenishing source of raw materials

How to build a bioreactor (installation) with your own hands

Biogas plants that extract gas from manure can be easily assembled with your own hands on your own site. Before assembling a bioreactor for manure processing, it is worth drawing drawings and carefully studying all the nuances, because. A container containing a large amount of explosive gas can be a source of great danger if it is used incorrectly or if there are errors in the design of the installation.

Biogas scheme

The capacity of the bioreactor is calculated based on the amount of raw material that is used to produce methane. In order for the operating conditions to be optimal, the reactor vessel is filled with waste at least two-thirds. For these purposes, a deep hole is used. In order for the tightness to be high, the walls of the pit are reinforced with concrete or reinforced with plastic, sometimes concrete rings are installed in the pit. The surface of the walls is treated with moisture insulating solutions. Tightness is a necessary condition for the efficient operation of the installation. The better the container is insulated, the higher the quality and quantity. In addition, the decay products of the waste are toxic and, if leaked, can be harmful to health.

A stirrer is installed in the waste container. It is responsible for mixing the waste during fermentation, preventing uneven distribution of raw materials and the formation of a crust. Following the agitator, a drainage structure is mounted in the manure, which facilitates the removal of gas into the storage tank and prevents leakage. It is necessary to remove the gas for safety reasons, as well as to improve the quality of the fertilizers remaining in the reactor after processing is completed. A hole is made at the bottom of the reactor for. The hole is equipped with a tight cover so that the equipment remains airtight.

How to ensure active fermentation of biomass at home using a generator and other equipment: waste processing, composition and extraction

In order for the processing process in the bioreactor to proceed faster, heating is necessary. The ambient temperature is quite enough for manure processing to take place without outside help. But under adverse weather conditions, in the winter season, a mini-biogas plant needs an additional heat source, otherwise gas production becomes impossible. In order for bacteria to turn waste into gas, the temperature in the reactor must be above 38 degrees Celsius. It is not difficult to get biogas with your own hands, the main thing is to know certain manufacturing rules.

The tank is heated using a coil, which is placed under the reactor, or by installing electric heaters for direct heating of the tank. , processing waste into gas, is already in the raw material. To activate microorganisms and start the biogas production process, the temperature in the tank must be sufficient for fermentation. To facilitate monitoring of compliance with temperature conditions, automatic heating is connected to the reactor. It heats the container when loading fuel into it to the desired temperature and turns off the heating when the desired mark on the thermometer is reached. The temperature control device for which is easy to find in a gas equipment store will cope with the role of an automatic heater.

Temperature control module. It can be purchased at any hardware store.

Correct removal of gas from the bioreactor: drawings, use of technology

For easy removal of the resulting gas from the tank, biogas plants are equipped with a number of devices:

1. Vertically arranged plastic pipes with a large number of holes to facilitate the separation of gas from the feedstock. The top of the pipe should protrude above the waste mass, allowing the gas to escape freely.
2. A film laid over a container and forming a semblance of a greenhouse effect. It maintains the desired temperature inside the tank, and also prevents the gas from mixing with air.
   

   Sometimes the top of the container is covered with a dome made of concrete or other material. To prevent such a dome from flying away under the pressure of the resulting gas, it is carefully attached to the structure, tied with cables.

3. A gas outlet pipe is placed in the upper part of the reactor. The pipe is equipped with a tight locking mechanism so as not to violate the tightness of the structure. The newly released biogas, entering the outlet pipe, is saturated with water vapor and contains many impurities. occurs by condensation: cooling to ambient temperature, water settles in the form of condensate on the walls of the pipe. To avoid corrosion, the discharge pipe is installed in such a way as to facilitate the removal of condensate through the separator.
4. To rid biogas of hydrogen sulfide impurities, a filter of specially treated activated carbon is installed on its way to the storage, in which the mixture is oxidized to sulfur and settles in the sorbent.

WATCH VIDEO

A self-assembled biogas plant, processing manure into biogas at home, significantly reduces the cost of paying for heating and electricity. Such an installation will reduce the cost of providing a private house with heat, reduce the cost of farm products, thereby increasing the profitability of the economy. – the ability to turn waste into an energy source and an alternative to natural gas. Biogas is environmentally friendly and modern.

For owners of large farms, there is an acute issue in the form of manure, bird droppings, and animal remains. To solve the problem, you can use special installations designed to produce biogas. They are easy to make at home and operate over a long period with a high yield of ready-to-use product.

What is biogas?

Biogas is a substance obtained from natural raw materials in the form of biomass (manure, bird droppings) due to its fermentation. Various bacteria are involved in this process, each of which feeds on the waste products of the previous ones. There are such microorganisms that take an active part in the process of biogas production:

• hydrolysis;
• acid-forming;
• methane-forming.

The technology for obtaining biogas from ready-made biomass is to stimulate natural processes. Bacteria in manure should be provided with optimal conditions for rapid reproduction and efficient processing of substances. To do this, biological raw materials are placed in a tank closed from oxygen.

After that, a group of anaerobic microbes enters the work. They allow you to convert phosphorus-, potassium- and nitrogen-containing compounds into pure forms. As a result of processing, not only biogas is formed, but also quality approvals. They are ideal for agricultural use and are more efficient than traditional manure.

Ecological value of biogas production

Thanks to the efficient processing of biological waste, valuable fuel is obtained. Establishing this process helps prevent methane emissions into the atmosphere, which have a negative impact on the environment. This compound stimulates the greenhouse effect 21 times more than carbon dioxide. Methane can persist in the atmosphere for 12 years.

To prevent global warming, which is a global problem, it is necessary to limit the entry and spread of this substance into the environment. The waste obtained during the recycling process is a high-quality approval. Its use allows to reduce the amount of chemical compounds used. Synthetically manufactured fertilizers pollute groundwater and adversely affect the environment.

What affects the productivity of the manufacturing process?

With the correct organization of the production process for the production of biogas, from 1 cu. m of organic raw materials receive about 2-3 cubic meters. m of pure product. Many factors influence its effectiveness:

• ambient temperature;
• acidity level of organic raw materials;
• environmental humidity;
• the amount of phosphorus, nitrogen and carbon in the initial biological mass;
• particle size of manure or litter;
• the presence of substances that slow down the processing process;
• inclusion of stimulating additives in the composition of biomass;
• frequency of substrate supply.

List of raw materials used for biogas production

Getting biogas is possible not only from manure or bird droppings. Other raw materials can be used to produce environmentally friendly fuel:

• grain stillage;
• waste from the production of juices;
• beet pulp;
• waste from fish or meat production;
• beer pellet;
• dairy waste;
• fecal sediments;
• household waste of organic origin;
• waste from the production of biodiesel from rapeseed.

Composition of biogas

The composition of biogas after passing all the following:

• 50-87% methane;
• 13-50% carbon dioxide;
• impurities of hydrogen and hydrogen sulfide.

After purification of the product from impurities, biomethane is obtained. It is an analogue, but has a different nature of origin. To improve the quality of fuel, the content of methane in its composition, which is the main source of energy, is normalized.

When calculating the volumes of gases produced, the ambient temperature is taken into account. With its increase, the yield of the product increases and its caloric content decreases. The characteristics of biogas are negatively affected by an increase in air humidity.

Scope of biogas

Biogas production plays a significant role not only in preserving the environment, but also provides the national economy with fuel. It has a wide range of applications:

• used as a raw material for the production of electricity, automotive fuel;
• to meet the energy needs of small or medium enterprises;
• biogas plants play the role of treatment facilities, which makes it possible to solve.

Biogas production technology

For the production of biogas, actions should be taken that will accelerate the process of natural breakdown of organic matter. Before being placed in a sealed container with a limited supply of oxygen, natural raw materials are carefully crushed and mixed with a certain amount of water.

The result is the original substrate. The presence of water in its composition is necessary to prevent the negative impact on bacteria that can occur when substances from the environment enter. Without a liquid component, the fermentation process slows down significantly and reduces the efficiency of the entire biological installation.

Industrial-type equipment for the processing of organic raw materials is additionally equipped with:

• a device for heating the substrate;
• equipment for mixing raw materials;
• devices for monitoring the acidity of the environment.

These devices significantly increase the efficiency of bioreactors. Agitation removes the hard crust from the surface of the biomass, which increases the amount of gas released. The duration of processing of organic mass is about 15 days. During this time, it decomposes only by 25%. The maximum amount of natural gas is released when the degree of splitting of the substrate reaches 33%.

Biogas production technology implies daily renewal of the substrate. To do this, 5% of the mass is removed from the bioreactor, and a new portion of the raw material is placed in its place. The waste product is used as an endorsement.

Technology for the production of biogas at home

Biogas production at home occurs according to the following scheme:

1. Grinding of the biological mass is carried out. It is necessary to obtain particles whose size does not exceed 10 mm.
2. The resulting mass is thoroughly mixed with water. For 1 kg of raw materials, approximately 700 ml of the liquid component is needed. The water used must be potable and free of impurities.
3. The entire tank is filled with the resulting substrate, after which it is hermetically sealed.
4. It is advisable to thoroughly mix the substrate several times a day, which will increase the efficiency of its processing.
5. On the 5th day of the production process, the presence of biogas is checked and it is gradually pumped out into prepared cylinders using a compressor. Periodic removal of gaseous products is mandatory. Their accumulation leads to an increase in pressure inside the tank, which negatively affects the process of splitting the biological mass.
6. On the 15th day of production, part of the substrate is removed, and a fresh batch of biological material is loaded.

To determine the required volume of the reactor for processing biomass, it is necessary to calculate the amount of manure produced during the day. It is mandatory to take into account the type of raw materials used, the temperature regime that will be maintained in the installation. The tank used should be filled to 85-90% of its volume. The remaining 10% is necessary for the accumulation of the obtained biological gas.

The duration of the processing cycle is necessarily taken into account. When maintaining the temperature at +35°C, it is 12 days. We must not forget that the raw materials used are diluted with water before being sent to the reactor. Therefore, its quantity is taken into account before calculating the volume of the tank.

Scheme of the simplest bioinstallation

For the production of biogas at home, it is necessary to create optimal conditions for microorganisms that will break down the biological mass. First of all, it is desirable to organize the heating of the generator, which will entail additional costs.

• The volume of the container for storing waste must be at least 1 cubic meter. m;
• a hermetically sealed container must be used;
• insulation of a biomass tank is a prerequisite for its efficient operation;
• the tank can be deepened into the ground. Thermal insulation is installed only in its upper part;
• a hand mixer is mounted in the container. Its handle is brought out through a hermetic assembly;
• nozzles are provided for loading / unloading raw materials, biogas intake.

Underground reactor manufacturing technology

For the production of biogas, you can install the simplest installation, deepening it into the ground. The manufacturing technology of such a tank is as follows:

1. Dig a hole of the right size. Its walls are poured with expanded clay concrete, which is additionally reinforced.
2. Holes are left on opposite walls of the bunker. They install pipes with a certain slope in order to pump raw materials and extract waste material.
3. An outlet pipeline with a diameter of 70 mm is installed almost near the bottom. Its other end is installed in a tank into which the waste sludge will be pumped out. It is recommended to make it rectangular.
4. The pipeline for supplying raw materials is placed at a height of 0.5 m relative to the bottom. Its recommended diameter is 30-35 mm. The top of the pipe is led into a separate tank for receiving prepared raw materials.
5. The upper part of the bioreactor should have a dome or cone shape. It can be made from ordinary roofing iron or other metal sheets. It is allowed to make a tank cover using a brick tub. To strengthen its design, the surface is additionally plastered with the installation of a reinforcing mesh.
6. I make a hatch on top of the tank lid, which should be hermetically closed. A gas pipeline is also removed through it. Additionally, a pressure relief valve is installed.
7. To mix the substrate, several plastic pipes are installed in the tank. They must be immersed in biomass. Many holes are made in the pipes, which makes it possible to mix the raw materials with the help of moving gas bubbles.

Biogas yield calculation

The yield of biological gas depends on the content of dry matter in the raw material and its type:

• from 1 ton of manure from cattle, 50-60 cubic meters are obtained. m product with a methane content of 60%;
• 200-500 cubic meters are obtained from 1 ton of plant waste. m of biogas with a methane concentration of 70%;
• 1300 cubic meters are obtained from 1 ton of fat. m of gas with a methane concentration of 87%.

To determine the efficiency of production, laboratory tests of the raw materials used are carried out. Its composition is calculated, which affects the quality characteristics of biogas.

Biogas is a mixture of gases that are formed during the decomposition of organic matter by anaerobic bacteria. Biogas is highly flammable and forms a clean flame when burned, so it can be used not only for cooking, but also for internal combustion engines (for example, for the production of electricity).

Advantages of a biogas plant at home:
- you can easily get biogas at home without the use of expensive equipment;
- an excellent alternative energy for those whose housing is located far from civilization, or for those who wish to be independent of the state;
– available raw materials (manure, kitchen waste, shredded vegetation, etc.);
– concern for the environment, since in the process of decomposition of organic substances in nature, gas enters the atmosphere, which entails a greenhouse effect, and in this case, biogas will be burned, while producing CO2;
– obtaining fertilizers as a by-product of a biogas plant.

But apart from the advantages, biogas plant has its drawbacks:
- bacteria work at a temperature of 18-40 degrees, so you can get biogas in the summer. If the biogas plant is insulated and equipped with heating, then it is possible to obtain biogas in the spring-autumn period, but the costs of insulation and heating may negate the benefit
- it is necessary to constantly introduce new raw materials, and therefore drain fertilizers.

To make a biogas plant with our own hands, we need:
1. Two barrels for 200l
2. Barrel for 30-60 liters, or a large plastic bucket
3. Plastic sewer pipes
4. Gas hose
5. Faucet

For clarity, I will diagram of a home biogas plant

The principle of operation of a biogas plant. Raw materials (manure, kitchen waste, chopped vegetation, etc.) and water are loaded into the reactor. The biogas plant will not work immediately, but after a few days, when the number of anaerobic bacteria will increase to a maximum.

During the life of anaerobic bacteria, biogas is released, which will be collected at the top of the barrel (a tap should be located in this place). From the reactor, biogas enters the collector through a gas hose.

The collector is a barrel of 200 liters of water, and a bucket inverted in it to collect gas, as well as to create the pressure necessary for the operation of a gas furnace. As gas enters, the bucket will float. If the amount of biogas is greater than the plastic bucket can hold, then the gas will simply go out through the water.

For the manufacture of the reactor You will need a sealed barrel of 200 liters. We make several holes in the upper part of the barrel and install:
– Plastic pipe for pouring raw materials. At the end of the pipe, it is necessary to install a transition to a large pipe (a kind of watering can, for the convenience of pouring raw materials)
– A plastic pipe for draining fertilizers. Since a biogas plant is not a perpetual motion machine, and it is necessary to constantly bring in raw materials. When new raw materials are introduced, the surplus (already processed raw materials - fertilizers) will exit through the drain pipe.
– Tap at the highest point of the barrel for collecting biogas.

In the manufacture of the reactor, it is very important that all connections are tight, otherwise, under the pressure that has arisen, the gas may leak out. The drain pipe must be located below the installation level of the gas cock. The drain and fill pipes must be tightly plugged when not in use.

To make a collector, you will need a 200 l plastic barrel without a lid. Pour 3/4 of the water into the barrel and install another barrel, upside down, smaller in volume. In the bottom of the barrel of a smaller volume, we cut a fitting for connecting a hose from the reactor, and a tap for connecting a hose going to a gas furnace.

To fill the raw materials, open the inlet and outlet and fill in the raw materials. It is best to use manure diluted in water. It is best to use rainwater or settled water so that the chlorine content from the water supply does not reduce bacteria colonies. Also, if you are using kitchen waste, keep detergents, egg shells, bones, and onion scales out of the way, as these can adversely affect the operation of the biogas plant.

Biogas itself has a very unpleasant smell, but there is no smell when burning. If you burn gas without mixing with air, you will get a yellow flame with soot, which will easily smoke the bottom of the pan.

If biogas is mixed with air and then ignited, we get a pure blue flame without soot. So, for example, in factory gas stoves, the instructions say that when switching from main gas to bottled gas and vice versa, it is necessary to change jets (which differ in hole diameter), otherwise the burner will smoke. Alternatively, you can use laboratory bunsen burner.

If you do not have a laboratory burner available, then it is easy to make it from a piece of pipe by drilling holes at the base. Thus, the gas passing through the pipe will mix with air, and at the outlet of the pipe we will get a mixed gas.

As jets, you can experiment with pieces of wood by sharpening them under a pencil and drilling holes of different diameters in them. In this way, the optimal flame size can be obtained.

For the experiment, an old barbecue was used as a stove, in the bottom of which a hole was cut and a Bunsen burner was installed. And later, the barbecue was replaced with a single-burner stove.

To create gas pressure, a weight is placed on the collector (a small barrel for collecting gas). For example, if you install a load of 5 kg, then 1 liter of water can be boiled in 15 minutes. If you install a load of 10 kg, then 1 liter of water will boil in 10 minutes.

Summing up, it should be noted that homemade biogas plant produces biogas for 30 minutes of burner operation per day, if the raw material is manure. If, however, kitchen leftovers are used as raw materials, then the productivity is only 15 minutes per day.

The emitted gas is not so much, but you must admit that the biogas plant is not so big either. Therefore, if you want to increase the amount of gas produced, you will need to increase the reactor and collector volumes.

The dimensions of the collector may not be increased if you pump the biogas into another container (for example, into a cylinder) in a timely manner. Most simply, this can be done with a compressor from a refrigerator, which has one inlet and one outlet. We connect the input to the collector, and the output to the cylinder.

The compressor can be equipped with automation, for example, when the collector is filled with gas, the barrel rises, closes the contacts, thereby turning on the compressor. And the compressor, in turn, turned off when the barrel dropped to the minimum level.

Biogas plant reactor must be made of plastic, but, in no case from metal, because due to oxidative processes, the metal will quickly rust. Alternatively, you can use plastic barrels of large volumes (for example, eurocube). And so that large volumes of barrels do not take up much space in the yard, they can be buried.

Nov 19, 2016 Gennady

The issue of obtaining methane is of interest to those owners of private farms who breed poultry or pigs, and also keep cattle. As a rule, such farms produce a significant amount of organic animal waste, and it is they who can bring considerable benefits, becoming a source of cheap fuel. The purpose of this material is to tell you how to get biogas at home using these very wastes.

General information about biogas

Derived from various manure and bird droppings, domestic biogas mostly consists of methane. There it is from 50 to 80%, depending on whose waste products were used for production. The same methane that burns in our stoves and boilers, and for which we sometimes pay a lot of money according to the meter readings.

To give an idea of ​​the amount of fuel that can theoretically be obtained by keeping animals at home or in the country, we present a table with data on the yield of biogas and the content of pure methane in it:

As can be seen from the table, for the efficient production of gas from cow dung and silage waste, quite a large amount of raw materials will be needed. It is more profitable to extract fuel from pig manure and turkey droppings.

The rest of the substances (25-45%) that make up home biogas are carbon dioxide (up to 43%) and hydrogen sulfide (1%). Also in the composition of the fuel there is nitrogen, ammonia and oxygen, but in small quantities. By the way, it is thanks to the release of hydrogen sulfide and ammonia that the dunghill emits such a familiar “pleasant” smell. As for the energy content, 1 m3 of methane can theoretically release up to 25 MJ (6.95 kW) of thermal energy during combustion. The specific heat of combustion of biogas depends on the proportion of methane in its composition.

For reference. In practice, it has been verified that for heating an insulated house located in the middle lane, about 45 m3 of biological fuel per 1 m2 of area per heating season is required.

By nature, it is arranged in such a way that biogas from manure is formed spontaneously and regardless of whether we want to receive it or not. The dung heap rots within a year - one and a half, just being in the open air and even at sub-zero temperatures. All this time, it emits biogas, but only in small quantities, since the process is extended in time. The reason is hundreds of species of microorganisms found in animal excrement. That is, nothing is needed to start gassing, it will occur on its own. But to optimize the process and speed it up, special equipment will be required, which will be discussed later.

Biogas technology

The essence of efficient production is the acceleration of the natural process of decomposition of organic raw materials. To do this, the bacteria in it need to create the best conditions for the reproduction and processing of waste. And the first condition is to place the raw material in a closed container - a reactor, otherwise - a biogas generator. The waste is crushed and mixed in the reactor with the calculated amount of pure water until the initial substrate is obtained.

Note. Clean water is necessary so that substances that adversely affect the vital activity of bacteria do not get into the substrate. As a result, the fermentation process can be greatly slowed down.

The industrial plant for the production of biogas is equipped with substrate heating, mixing facilities and control over the acidity of the medium. Agitation is performed to remove the hard crust from the surface, which occurs during fermentation and interferes with the release of biogas. The duration of the technological process is at least 15 days, during which time the degree of decomposition reaches 25%. It is believed that the maximum fuel yield occurs up to 33% of biomass decomposition.

The technology provides for daily renewal of the substrate, thus ensuring intensive production of gas from manure, in industrial installations it amounts to hundreds of cubic meters per day. Part of the spent mass in the amount of about 5% of the total volume is removed from the reactor, and the same amount of fresh biological raw materials is loaded in its place. The waste material is used as organic fertilizer for the fields.

Scheme of a biogas plant

By obtaining biogas at home, it is impossible to create such favorable conditions for microorganisms as in industrial production. And first of all, this statement concerns the organization of heating the generator. As you know, this requires energy, which leads to a significant increase in the cost of fuel. It is quite possible to control compliance with the slightly alkaline environment inherent in the fermentation process. But how to correct it in case of deviations? Again costs.

Owners of private households who want to produce biogas with their own hands are advised to make a reactor of a simple design from available materials, and then upgrade it to the best of their ability. What need to do:

• a hermetically sealed container with a volume of at least 1 m3. Different tanks and barrels of small sizes are also suitable, but little fuel will be released from them due to an insufficient amount of raw materials. Such volumes of production will not suit you;
• organizing the production of biogas at home, you are unlikely to start heating the tank, but it is necessary to insulate it. Another option is to bury the reactor in the ground by thermally insulating the upper part;
• install a manual stirrer of any design in the reactor, pulling the handle through the top cover. The handle passage assembly must be airtight;
• provide nozzles for supplying and unloading the substrate, as well as for sampling biogas.

Below is a diagram of a biogas plant located below ground level:

1 - fuel generator (tank made of metal, plastic or concrete); 2 - bunker for pouring the substrate; 3 - technical hatch; 4 - a vessel that plays the role of a water seal; 5 - branch pipe for unloading waste; 6 – biogas sampling pipe.

How to get biogas at home?

The first operation is the grinding of waste to a fraction whose size is not more than 10 mm. So it is much easier to prepare the substrate, and it will be easier for the bacteria to process the raw materials. The resulting mass is thoroughly mixed with water, its amount is about 0.7 l per 1 kg of organic matter. As mentioned above, only clean water should be used. Then the substrate is filled with a do-it-yourself biogas plant, after which the reactor is hermetically sealed.

Several times during the day you need to visit the container to mix the contents. On the 5th day, you can check the presence of gas, and if it appears, periodically pump it out with a compressor into a cylinder. If this is not done in time, then the pressure inside the reactor will increase and fermentation will slow down, or even stop altogether. After 15 days, it is necessary to unload part of the substrate and add the same amount of new. Details can be found by watching the video:

Conclusion

It is likely that a simple biogas plant will not meet all your needs. But, given the current cost of energy resources, this will already be a considerable help in the household, because you do not have to pay for raw materials. Over time, closely engaged in production, you will be able to catch all the features and make the necessary improvements to the installation.

The growing popularity of alternative methods of obtaining heat and electricity has led to the desire of many owners of country houses and cottages to obtain a certain autonomy from external energy suppliers. Moreover, “purchased” energy shows a constant tendency to increase prices, and the maintenance of a country economy is getting more and more expensive every day. A biogas plant is an excellent alternative for external energy sources. At a minimum, it can provide the house with combustible gas for the stove, and with an increase in power (if there is enough of its own or purchased waste), it can provide both heating and electricity for both the house and the entire household.

Who needs biogas plants

Biogas plants are used to produce combustible gases from biological raw materials. So they are needed wherever combustible gases are required. That is, to obtain thermal and electrical energy.
First of all, biogas plants are necessary for those farms where there is a lot of raw materials in the form of biological waste. Thus, it is possible not only to make production waste-free, but also to significantly increase its profitability - due to independent energy production, the absence of costs for the purchase of both thermal and electrical energy.

Vladimir Rashin, a designer of a biogas plant and a farmer from Perm, proved from his own experience that agricultural production, which independently utilizes waste using an appropriate device, fully meets its needs for heat and electricity, as well as combustible gas. In his quail farm, biogas is used for heating premises (both residential and utility and industrial), for generating electricity, in cookers, and also for refueling vehicles - all cars of the Rashin farm run on biogas. In this case, the main raw material for the biogas plant is quail manure. At the output, in addition to biogas, organic fertilizer is also obtained, which also brings additional income to the farm.

Biogas plants like Vladimir Rashin's can significantly increase the profitability of any agricultural production. As a raw material for biogas production, not only manure can be used, but also various waste products from woodworking industries (bark, sawdust, and so on), and almost any organic matter.

In addition, biogas plants can also be used in country houses and cottages, even if such farms do not have a farming orientation. Household waste from any farm will be enough to provide raw materials for an individual biogas plant, and if the farm is not fully provided with thermal and electrical energy, then at least reduce the cost of purchasing such energy. In addition, in addition to household waste, in any suburban economy there is also waste from a personal plot (weeds, cuttings of branches, and so on). Well, it is possible to provide a stove with combustible gas even with the help of a mini-biogas plant in country conditions.

The principle of obtaining biogas

Biogas is produced by anaerobic (that is, without oxygen) fermentation of biomass, which is provided by special bacteria. Three types of bacteria are involved in the process: hydrolytic, acid-forming and methane-forming.

The biogas plant consists of several parts (tanks). First, the raw material enters the preliminary tank, where it is thoroughly mixed and crushed (in the case of a solid fraction) to a homogeneous mass. Then the crushed raw material enters the reactor (a container where the biomass is directly fermented).

The reactor is usually made of acid-resistant reinforced concrete. This container is completely sealed. In order to speed up the fermentation process, the liquid in the container is heated and mixed. Most often, a cogeneration plant is used to heat the reactor - in such an installation, it is necessary to cool the heat and power generator, and the removed heat enters the reactor. Also, heat can come from a special hot water boiler.

After the fermentation process is completed, the generated gas from the reactor enters the gas holder, where the pressure is equalized, and then the biogas enters the heat and power generator (gas or diesel-gas), as a result of which thermal or electrical energy is produced.

In addition to biogas, a solid fraction is deposited in the reactor - organic fertilizers, which can then be used in the fields. Liquid fertilizers are also obtained from the reactor - after the release of gas. Both liquid and solid fertilizers are concentrated and are actively used in agriculture.

Industrial biogas plants have automatic control. Automation is responsible for the flow of raw materials into the installation, and for mixing, controls the temperature, the operation of the generator, and so on. Also, such installations are equipped with emergency flare devices - in case the engine stops, then the gas is simply burned. In addition, industrial biogas plants are often equipped with a line for packaging liquid fertilizers, in which case fertilizers are bottled into small (up to 1 liter) bottles.

Individual biogas plant

The principle of operation of an individual biogas plant is the same as that of an industrial one. True, mini-installations are rarely equipped with automatic devices for mixing the substrate and other automation - due to the significant increase in the cost of a household installation with such a configuration. Most often, these plants have only temperature control devices, generator operation, and so on, and all maintenance of the mini-biogas plant is carried out manually.

Household biogas plants are used mainly for the production of combustible gas for kitchen needs, if the farm does not have a livestock or crop-growing orientation. However, there is an increasing trend towards the use of mini-installations to provide country houses and cottages with a complete energy complex, that is, not only "kitchen" gas, but also thermal and electrical energy. Moreover, it no longer depends on the presence of large or small livestock on the farm, raw materials for home biogas plants are simply purchased from the nearest farm. It can be both manure and woodworking waste.

DIY biogas plant

The construction of biogas plants, even mini ones for domestic needs, is not cheap. And, although the payback period for such equipment is relatively short (5-7 years), not every owner is ready or has the opportunity to invest the required amount. Yes, the advantages are obvious: after a short time, with the help of a mini-biogas plant, you can get almost complete autonomy from purchased energy sources, transfer your farm to self-sufficiency, and even have free fertilizers as additional bonuses. However, you need to pay money today, and the advantages will appear only in a few years. Therefore, many owners of country houses and cottages are wondering: how to make a biogas plant on their own?

A mini biogas plant is not that complicated, and its construction is quite manageable. This saves a significant amount. In addition, there are projects of biogas plants using improvised means and materials (for example, with a bell reactor, moreover, the bell can be made of rubber, and so on). That is, home-made installations for the production of biogas is the acquisition of the desired bonuses for minimal money.

When building a biogas plant, it is necessary to make an accurate calculation - what should be its performance. To do this, all desired consumers of biogas should be taken into account (for example, a cooker, automotive equipment, etc.). If biogas is planned to be used to generate electricity and/or heat energy, then the calculation should include all energy consumers. Based on the calculation, a biogas plant project is created.

Homemade biogas plants are widely represented on the Internet. You can find sample calculations, and a drawing of the device, and a detailed description. A huge selection of devices will make it possible to manufacture both a complex installation with several chambers and a simplified version (for example, such a simple device as a cesspool covered with a rubber bell with a gas outlet device). Everyone will be able to choose a home-made installation in accordance with their desires, capabilities and skills. Particularly useful in this case are descriptions accompanied by step-by-step photographs or videos.

Making a biogas plant with your own hands allows you to save up to 50% of the cost of the device, which significantly speeds up the payback of equipment. In addition, making the simplest installation to start with allows you to assess the need for such equipment on the farm, as well as invest money gradually, which for many is much easier than paying the entire amount right away.

How does a biogas plant work?