A real long-burning boiler for burning chicken manure, horse manure. Biofuel boilers

Litter from poultry farms is a by-product of poultry farming, which is several times larger than the output of finished products: up to 3 tons of turkey meat is produced per 1 ton of broiler meat - up to 4 tons of litter: poultry farms in Russia produce more than 17 million tons of litter per year. For the present, the point of view on it as a hazardous waste that reduces the profitability of production still prevails. This encourages poultry farmers to get rid of it in the cheapest possible way - by taking it to landfills. Pyrolysis and biogas production as manure disposal methods have not been widely used for a number of reasons. The production of pyrolysis gas from bedding manure is technologically inefficient, because the original manure is a more calorific fuel than pyrolysis gas. A biogas plant is a high-tech production that has a number of significant limitations (the temperature at which biogas is released should not go beyond the established limits: in mesophilic mode: 35±1.0; in thermophilic mode: 55±0.5ºС). After the end of the process of biogas release, liquid waste requiring disposal remains 4-5 times more than the original litter. All the biogas generated will not be enough to dry them. Therefore, biogas production is essentially not a method of biowaste disposal.

Video: Burning bedding manure in a steam boiler

AGK ECOLOGIA LLC offers direct combustion of bird droppings in specialized hot water and steam boilers. At the same time, the rate of thermal utilization of one portion of the litter is 10-15 seconds. With the proper organization of the combustion process, the concentration of emissions is less than when burning fuel oil, and the resulting ash (up to 14% of the initial volume of waste) is an effective potash-phosphorus fertilizer. Thus, the process of burning manure is characterized by the absence of secondary waste, which makes the technology environmentally sound.

According to the technology we offer, manure is a secondary raw material and a source of additional income. Bird droppings is a raw material for the production of:

• energy resources (heat, steam, electricity) when it is burned in the form of biofuel with the side production of mineral fertilizers from the ash.
• organic fertilizers;

C b about To a greater extent, the thermal disposal process is applicable to bedding manure, which does not require any preparation before incineration. We offer litter thermal utilization technology with the production of up to 2 Gcal of heat (DHW, heating) from 1 ton of this waste, or 3 tons of steam, or up to 600 kWh of electricity, replacing up to 270 m 3 of gas. Additionally, up to 140 kg of ash is obtained - an effective mineral fertilizer. The technology of flare-layer burning of manure is protected by Patent No. 151541 (MKP F23G 7/00).

Specific capital costs for hot water boilers are 10-12 thousand € / t of manure per day, and the payback period does not exceed 2 years only by reducing (or stopping) gas consumption (1 € = 75 rubles).

Below you can watch a detailed video about the process of effective disposal of manure using our equipment.

Specific capital costs for steam boilers range from 20 to 17 thousand €/t of manure per day, the cost of heat is about 400 rubles/Gcal. In the case of combined heat and power production, capital costs increase to 36-25 thousand €/t of manure or 2000-1300 €/kW of installed capacity, decreasing with the increase in CHP capacity. The cost of electricity is in this case from 2.4 to 0.7 rubles/kWh. The payback period of investments ranges from 2 (hot water boilers) to 5 years (mini-CHP with combined production of electricity, steam, heat and fertilizers).

Utilization of cell litter is complicated by its high (70-75%) humidity, and requires its preliminary drying (including due to the heat of the combustion products of a part of the already dried litter). With its constant combustion in boilers, drying to a moisture content of 30% is sufficient. If long-term storage is required, the litter should be dried to a moisture content of no more than 15%. In this case, it can also be used as an organic fertilizer. When drying cell manure, it is necessary to clean the gases after the dryers not only from fly ash entrainment, but also from foul-smelling gases. Absorbers such as wet scrubbers with circulating alkaline water are commonly used for this purpose.

Video: Burning cell waste

But that's not all. Litter disposal by burning it leads to the formation of ash, which is a valuable potassium-phosphorus mineral fertilizer that increases crop yields by 10-15%. The volume of the resulting ash will be 7-10 times less than the volume of the original manure. Depending on the requirements of technical specifications, ash can be packaged in bags (big bags) or transported to the place of use in bulk in closed transport.

Schematic diagram of a steam boiler house

The efficiency of using cell manure as a biofuel increases with minimization of its initial humidity: its decrease from 75 to 65% increases useful heat by 5 times: from 0.1 to 0.5 Gcal/t of manure due to a reduction in fuel consumption for drying.

LLC AGK ECOLOGIA offers to pre-dry the manure using the heat of the air removed from the poultry houses. The recovery of this heat makes it possible to reduce the humidity of the manure to 55-60%. The useful heat output in this case increases to 0.7 Gcal/t of manure, which makes it possible to generate a sufficiently large amount of heat or saturated steam for production needs, while saving natural gas.

Specific capital costs for the creation of such an energy complex are up to 700 thousand rubles / ton of manure per day, and their payback period does not exceed 5-6 years. The cost of thermal energy is 700 rubles/Gcal, steam - 500 rubles/ton. The accompanying product in this case is the formation of 50-60 kg of ash (per 1 ton of raw manure). The production of soil conditioner from this ash increases crop yields by 30-40%, which can significantly reduce the cost of feed and, accordingly, the final poultry products.

Thermal technology is also applicable for

• Disposal of chicken manure
• Burning chicken manure
• Cattle and pig manure processing
• Litter processing
• Bird droppings processing

Fuel - chicken manure mixed with sunflower husk bedding, dried to a moisture content of 23%.

The experimental setup is a vortex furnace made in the form of a remote pre-furnace.

Results of the chicken manure burning experiment

Place of the experiment - Volnyansk

Time - 26-27.01.2011

Air temperature in the room - + 13- + 15оС

Air temperature outside - -15оС

Fuel - chicken manure mixed with sunflower husk bedding, dried to a moisture content of 23%. Other data on calorie content, fractional composition, volatile yield, and also on the composition of the mineral part are not available.

Brief description of the installation: the experimental installation is a vortex furnace, made in the form of a remote pre-furnace. The pre-furnace is installed in the immediate vicinity of the E10-14 steam boiler, and connected to it by a heat-insulated gas duct and used with the TDM and the existing boiler automation system, is structurally made according to the following scheme. Cylindrical body lined with nutria with refractory material, to organize the vortex movement, it is equipped with two swirlers (upper and lower), 4 blow zones located along the height. In the upper zone there is a unit for tangential fuel injection with a primary air supply for the purpose of joint injection with fuel. A swirler is installed above the upper blast zone, into which secondary blast air is supplied to form an organized release of flue gases from the vortex pre-furnace. The lower blast zone consists of a lower swirler with a central hole for ash discharge and main blast nozzles. Secondary air is supplied to the middle blast zones in order to maintain the stability of the vortex flow in height.

Description of the experiment:

The system of pneumatic transport to the reactor was tested, the vortex motion in the furnace was organized. Air is supplied to the following zones:

Ejector;

Bottom swirler:

Lower blast nozzles of the main blast.

The remaining blast zones are practically disabled due to the high resistance of the gas path.

The installation was started from a cold state by igniting the kindling material. The fuel supply system worked reliably. The vortex was in a stable state. Deposits on the walls of the reactor and the hearth were not observed. The temperature in the reactor is 800-1100°C, depending on the fuel consumption, which is set by changing the number of feeder revolutions.

Continuous permanent operation was not possible due to the lack of water in the boiler and, accordingly, the utilization of heat from the plant.

In general, during the day it was necessary to launch the vortex pre-furnace three times, the launches were carried out without difficulty with a quick exit to operating modes.

01/27/2011 (after 15 hours).

2-3 trial starts were made on wood, the ignition mode was tried in a hot firebox. Temporary shutdowns were associated with the freezing of fuel in the bunker and the operation of the boiler safety system. All blast zones are completely closed, except for the lower row of main blast nozzles due to lack of fuel for transportation.

Boilers operating on bird droppings. Our company specializes in the development, creation, implementation, adjustment and commissioning of boiler houses for agricultural enterprises.

The development of the agrarian complex of Ukraine is unthinkable without the development of poultry farming. However, the growth of this area of ​​agricultural business entails an increase in the amount of waste in the form of litter. In the traditional approach, bird droppings are considered as toxic production wastes of the III hazard class. Its placement in open areas leads to severe environmental pollution. Therefore, the level of soil, groundwater and air pollution in the leading poultry-farming regions is several times higher than the permissible norms.

Our experts have developed several methods for the disposal of bird droppings.

Litter disposal can be converted into a profitable business by making fertilizer. However, there is another way - the use of manure to heat the poultry houses themselves, as well as domestic and administrative premises.

The use of bedding manure in the form of fuel has very great prospects.

The main advantage of the proposed method of disposal of litter manure are:

• complete and rapid disposal of waste of hazard class III;
• obtaining permanently used types of thermal and/or electrical energy and valuable mineral fertilizers;
• good adaptation to existing systems of heat and power supply of poultry farms. It is also possible to burn cell litter when its final moisture content is not more than 50% by preliminary mixing with dry wood or plant waste, or by preliminary drying of the litter with the products of its combustion.

Bedding manure can serve as a renewable alternative biofuel that is used for the poultry farm's own needs, replacing natural gas or other natural fuel. Burning of bedding manure does not require its preliminary preparation (granulation, grinding, drying, etc.). This simplifies and reduces the cost of the technological process.

Burning 1 ton of bedding manure saves up to 270 m3 of natural gas or up to 240 kg of liquid fuel (fuel oil, heating oil). In this case, it is possible to obtain up to 2 Gcal of heat in the form of hot water or up to 3 tons of steam for technological needs, or to generate from 50 to 500–600 kW of electricity (depending on the initial and final parameters of the steam).

As a fuel, bedding manure has the following thermal characteristics (per working weight):

The ash formed during the burning of bedding manure is a complex phosphorus-potassium-lime fertilizer with a high content of trace elements and can be used for various crops at doses from 2 to 10 c/ha, depending on the type of soil, crops and method of application. It is applied to the soil in a dry form without additional processing. According to the results of experimental data, the use of this ash instead of conventional mineral fertilizers increased crop yields by 10–15%. The yield of ash is 10-15% of the amount of the original litter.

Reliable burning of litter manure became possible with the creation of special combustion devices that combine layered combustion of fuel with vortex combustion. The design of the furnace with a multi-zone air blast system provides the necessary combustion conditions for this high-moisture, low-calorie, high-ash fuel with minimal ash carryover. The results of test tests on the combustion of 56 tons of bedding manure in an industrial plant with a thermal power of 1.5 MW showed that it burns efficiently with minimal emissions of harmful substances into the atmosphere. To prevent slagging of the heating surfaces during the test period, the temperature of the gases at the outlet of the furnace was maintained within 950 ± 50 °C.

The fuel depot is equipped with a service tank with a "live" bottom. Steam from the boiler (pressure up to 1.4 MPa, temperature up to 190 °C) is directed to technological needs, to the boiler of the DHW system and to the auxiliary needs of the boiler house. The ash caught in the furnace, the bunkers of the convective flue of the boiler and the ash catcher is continuously removed to the ash storage. Depending on the requirements of the consumer, the ash can be packed in bags or transported to the place of use in bulk in closed transport. For a boiler house designed to burn 75-80 tons of PP per day and having a thermal capacity of ~ 7–8 Gcal / h (8 - 10 t / h of saturated steam at a pressure of 1.4 MPa), a room with a size of ~ 18 × 15 m and a height of up to 13 m. The boiler room can be made of prefabricated metal structures with sandwich panels based on mineral basalt insulation 100–150 mm thick with a fire resistance limit of 0.75–1.5 hours.

The fuel warehouse should be located in a closed unheated room with an area of ​​at least 300 m2 (18 × 18 m), up to 6 m high and can also be made of prefabricated metal structures with sandwich panels. The economic efficiency of bedding manure burning and the payback period of capital expenditures depend on its quantity. The burning of bedding manure with the generation of steam and heat is a cost-effective and fast payback measure. The estimated payback period does not exceed 18 months. Supplementing steam and heat production with electricity generation will significantly increase the economic efficiency of this method of PP utilization. So, when generating 10 t/h of steam with parameters of 1.4 MPa and 250 °C in the heating mode with heating of network water up to 80 °C (DHW mode), approximately 900 kWh of electricity can be generated, of which up to 200 kWh - for the boiler house, and the rest - for the poultry farm's own needs.

This method of PP disposal is the fastest with a payback period of capital expenditures of no more than 1.5–2.0 years. The components of capital costs and economic efficiency depend on the actual conditions and are calculated for each specific case. The integrated generation of heat for hot water supply and heating, process steam and electricity in boiler houses on bedding manure will significantly increase the independence of poultry farms from energy suppliers and tariffs for them.

Mr. Vladimir Rabinovitch, B.Sc., CMfg.E.

Business Development Manager

Hitec Machinery Canada

Toronto, Ontario, Canada

Tel: 1-416-567-8701

e-mail: [email protected]

In the article by Mr. Lysenko V.P. “Ecological problems of poultry farms in Russia and the role of biotechnology in the processing of organic waste” correctly reflects the current problems of recycling chicken manure.

In the information below, we provide a brief description of a Canadian technology that solves the environmental problems associated with manure and at the same time turns it into a valuable fuel.

A group of Canadian companies has the technology and manufactures equipment for converting chicken manure into dry fuel and generating heat and electricity. Dry chicken manure has almost the same caloric content as wood, and if there is a technology for drying and burning it with high efficiency, then the manure turns into a valuable fuel.

We turn raw chicken manure into dry dust and burn this dust in the most efficient way.

Drying litter.

Canada releases system BPS, which simultaneously dries and grinds biomass (pictured).

Zharkov G. V. *, Ph.D. Drunk K. E. **, Pupin V. B. ** .
* LLC "Adaptika" ( town White Coast, Bryansk, Russia),
** Institute of Gas NASU (Kyiv, Ukraine)

annotation. With the development of poultry farming, the problem of recycling chicken manure is becoming increasingly important. Litter is a strong pollutant of the soil, water and air basins. At the same time, manure is a valuable raw material for the production of fertilizers, feed additives and an energy resource. A comparative analysis of various directions of litter utilization is given. The most effective is an integrated approach to recycling, which is based on the production and gasification of pellets from bedding manure using coke-ash residue as a high-quality fertilizer and the generation of electrical and thermal energy for own needs and external consumers. The compositions of the generator gas obtained during the gasification of pellets from bedding and native manure are given. The scheme of the enterprise for the complex processing of litter is proposed.

Currently, the most dynamically developing branch of agriculture in the region is poultry farming. It achieves the highest return of production per unit of feed consumed. As a result, from 2008 to 2012, the Russian Federation experienced a steady increase in the poultry population. During this period, it increased by 123.4 million heads. The increase in 2012 alone amounted to more than 24 million heads, reaching 394.2 million heads by the beginning of 2013. Obviously, like every booming industry, the poultry industry has growing pains. One of the most painful problems is the problem of disposal of chicken manure.

On December 2, 2002, the Ministry of Natural Resources of the Russian Federation approved the "Federal Classification Catalog of Waste", in which bird droppings are included as a substance of hazard class III. Poultry farms began to impose serious penalties for the disposal of the so-called "hazardous waste".

Taking into account the Decree of the Government of Russia dated 12.07.2003 No. 344 “On the standards of payment for emissions of pollutants into the atmospheric air by stationary and mobile sources, discharges of pollutants into surface and underground water bodies, disposal of production and consumption wastes” for disposal of waste of hazard class III ( bird droppings) poultry farms are charged a fine of 497 rubles. per ton, if bird droppings are not disposed of in poultry farms, but are accumulated in storage facilities. Currently, according to the Ministry of Agriculture, payments by agricultural companies for the placement of manure and other waste on their lands reach 35 billion rubles. per year, excluding fines for environmental pollution.

Litter-free manure is 10 times more dangerous than municipal waste in terms of chemical pollution of the environment. Being a favorable environment for the preservation and development of various microorganisms and helminths, litter poses a threat of contamination of water bodies, soil, groundwater, feed and pastures with pathogens dangerous to humans and animals. According to the World Health Organization, more than 100 species of various animal and human pathogens can successfully develop in this environment.

The highest level of environmental stress is experienced by the fields of disposal of litter-free manure. The area of ​​fields contaminated with organic waste, including livestock, in the Russian Federation exceeds 2.4 million hectares, with 20% being heavily polluted, 54% being polluted, and 26% being slightly polluted. These lands are a constant source of pollution of the biosphere. With long-term storage of manure on soil areas open to atmospheric precipitation, environmental problems are inevitable. In the surface layer of the soil (0.4 m), the level of mineral nitrogen reaches 4950 kg/ha, including the level of nitrate nitrogen exceeds 2500 kg/ha, which is 17 times higher than in unpolluted soil. In groundwater, the content of nitrate nitrogen exceeds its content in drainage water from the field by 2 times, ammonia nitrogen - 8 times, phosphorus - 11 times, potassium - 10 times. Only environmental damage from violation of the regulations for the use of litter-free manure is currently estimated at 150 billion rubles. The damage from causing harm to the health of people and animals cannot be estimated even approximately. The incidence rate of the population in areas where large livestock enterprises and poultry farms operate is 1.6 times higher than its average in the Russian Federation.

The data presented confirm that well-organized waste disposal is very important both for the successful conduct of competitive production and for ensuring the coexistence of poultry farms and the population of adjacent territories.

Chicken manure is not only waste, but also a valuable raw material that must be used. It is known that bird droppings are:

• organic fertilizer with a high content of nutrients. Chicken manure as a fertilizer is superior to manure, it contains: nitrogen (N) - 1.6%, phosphorus (P) - 1.5%, potassium (K) - 0.8%, calcium (Ca) - 2.4% , magnesium (Mg) - 0.7%, sulfur (S) - 0.4%. It also contains trace elements: copper, manganese, cobalt, zinc, and amino acids;
• valuable feed additive. Dry chicken manure contains 26-38% crude protein, 12-14% fiber, 3-5% fat, 3-9% calcium, up to 5% phosphorus;
• biofuel, the lower calorific value of which is 3500...4000 kcal/kg dry weight, depending on the presence and composition of the litter.

The use of litter is not only technically possible, but also economically justified. It is of interest to create an enterprise designed for the integrated use of litter in all of the above areas. Let us outline the main provisions of this approach.

Litter as a raw material for the production of fertilizers. The essence of the process involves the production of granular fertilizers by the method of accelerated composting. This approach fully satisfies the requirements of the document "Veterinary and sanitary rules for the preparation for use as organic fertilizers of manure, dung and runoff for infectious and parasitic diseases of animals and birds" (approved by the Ministry of Agriculture and Food of the Russian Federation on 04.08.1997 No. 13-7-2 / 1027) and allows you to get a high-quality environmentally friendly product, for which there is a steady demand from agricultural producers. The requirements for quality, control methods, storage conditions, transportation, and even the norms for the use of such a product have already been developed and set out in GOST R 53117-2008 “Organic fertilizers based on animal waste. Specifications". There are ready-made solutions for accelerated composting, studies have been conducted on the effect of fertilizers based on composted manure on crop yields. It remains to select a set of equipment for the production of equipment, provide it with energy carriers and proceed to the formation of a network of consumers, production and sale. Obviously, if the cost of the produced fertilizers is not high, and the form is convenient for use, this product will be a significant competitor to traditional mineral fertilizers.

Litter as a component of feed for cattle . A feature of digestion in birds is the rapid movement of food through the alimentary canal. As a result, not all components and nutrients are absorbed. As a result, the content of such a valuable product as proteins in chicken manure exceeds 30%. The digestive tract of ruminants allows for efficient extraction of nutrients from feed. This makes it possible to use bird droppings as an additive to the natural diet of cattle. The use of unprocessed manure for these purposes is impossible: the characteristic smell, taste, pathogenic and conditionally pathogenic microflora do not allow the use of manure as a feed additive. However, drying and heat treatment can eliminate odors and destroy microflora. This opens up wide possibilities for the use of chicken manure. Studies on the effect of using manure as a top dressing were carried out in many countries, including the USSR, invariably showing good results. On this basis, back in 1976, the Ministry of Agriculture approved the “Temporary veterinary and sanitary requirements for dry poultry manure used for feeding farm animals."

Feeding in the form of prepared chicken manure can significantly increase the weight gain of animals during fattening, while reducing the cost of providing this weight gain. As in the case of the use of manure as a fertilizer, the requirements for widespread use are the same: low price and ease of use.

Litter as an energy resource. Immediately make a reservation that the use of native (without litter) litter to meet energy needs, we consider unreasonable. Mendeleev's phrase about oil can be fully applied to chicken manure. Native litter should be used in the directions above. With regard to bedding manure, the disposal of which is a real problem, and the results of processing are not so unambiguous, its reasonable use as an energy resource is absolutely justified. Several directions of such use are possible: production of biogas and its further use; direct combustion; gasification and use of the resulting gaseous fuel.

Biogas production involves anaerobic decomposition of manure, purification of biogas and combustion in gas piston engines to generate electricity and thermal energy by utilizing heat from engine exhaust gases.

Let us evaluate the efficiency of a cogeneration complex based on a biogas plant based on the following data:

• biogas yield during anaerobic decomposition of chicken manure with bedding with a moisture content of 60%, according to ZORG Biogas, reaches 90 m³ per 1 ton.
• calorific value of biogas - 5000-6500 kcal / nm 3;
• during the operation of gas piston engines in the form of thermal energy, up to 40% of the initial energy potential of the fuel can be obtained;

Analysis of the presented data shows:

• from 10 tons of manure with a moisture content of 45%, 13.75 tons of manure with a moisture content of 60% will be obtained
• the gas output will be 13.75 t/h ∙90 m³/t = 1237.5 m³/h;
• the energy potential of the resulting gas is 1237.5 m³ / h ∙ 5750 kcal / m³ = 7.12 (8.28 MW∙ h);
• which allows generating electricity - 8.28 MW ∙ 0.35 = 2.9 MW ∙ hour;
• in addition, the production of thermal energy will be 7.12 Gcal ∙ 0.4 = 2.85 Gcal.

Thus, the complex, designed for the production of biogas from 10 t / h of bedding chicken manure with a moisture content of 45% and the production of electrical and thermal energy, provides the generation of: 2.9 MW of electrical energy and 2.85 Gcal of thermal energy.

The advantages and disadvantages of this technology are known. We list the main problems: a long and rather thin process of processing raw materials, the need to maintain the temperature of the substrate above the ambient temperature, large volumes of fertilizers with high humidity (92 ... 95%) obtained during processing. A significant problem for such use of litter is also high specific capital investments for the creation of complexes, reaching for the analyzed case 2000 ... 2500 Euro per 1 kW of installed capacity.

direct combustion. Consider a similar situation involving the production of electrical and thermal energy. Bedding manure is burned in a steam boiler, the steam generated is used to generate electricity through a steam turbine. Considering the complexes under the same conditions, we obtain:

• the capacity of the manure processing complex is 10 t/h (at a moisture content of 45%);
• efficiency steam boiler operating on solid fuel - 82%;
• efficiency steam turbine generator when operating in condensing mode -25%.

Analysis of the presented data:

• let us take the specific lower calorific value of dry material 4000 kcal/kg, which is quite justified in the case of using sawdust as a filler. Then the total heat of combustion of bedding manure at a moisture content of 45% will be:
  4000 ∙ (1 -0.45) - 550 ∙ 0.45 \u003d 1952.5 kcal / kg

• the energy potential of manure burned in 1 hour in the boiler will be:
  1952.5 ∙ 10000 = 19.52 Gcal

• energy potential of steam obtained from manure:
  19.52 Gcal ∙ 0.82 = 16 Gcal (18.6 MW∙h)

• production of electrical energy using a steam turbine operating in a condensing mode:
  18.6 MWh ∙ 0.25 = 4.65 MWh.

It is also possible to operate the complex with a turbine, which provides for industrial steam extraction or heating mode. In this case, electricity production will be reduced, but the complex will be able to supply thermal energy.

Thus, a complex designed for direct combustion of 10 t/h of litter chicken manure with a moisture content of 45% and the production of electrical energy can generate up to 4.65 MW of electricity.

Compared to the technology discussed earlier, capital costs will be significantly lower. The average specific cost for the electricity generation complex for the steam cycle is 1500 Euro per 1 kW of installed capacity.

Unfortunately, burning bedding manure without pre-treatment is a complex task, the solution of which is associated with the need to ensure compliance with environmental standards. Humidity and composition of the litter being disposed of is not a constant value, which affects the operation mode of the equipment and the composition of emissions.

Much attention is paid to waste incineration in the world. Specific requirements for waste incineration are set out in Directive 2000/76/EC of the European Parliament on Waste Incineration. This document says that when burning non-hazardous waste, it is mandatory to maintain a temperature of at least 850 ° C in the furnace space and hold gaseous products at this temperature for at least 2 seconds. If hazardous wastes containing more than 1% halogenated organic compounds, expressed as chlorine, are incinerated, the temperature must be at least 1100 °C. The problems of direct burning and possible environmental risks significantly reduce the value of this approach to the use of manure.

Gasification. A real alternative to the technologies of biogas production and direct combustion can be the technology of gasification of chicken manure with the subsequent use of the produced generator gas to generate heat and electricity. It is important that the use of gasification technology is most effective within the framework of a multifunctional complex for the disposal of chicken manure. At the same time, the marketable products at the output of the complex are fertilizers, fuel pellets, electrical and thermal energy.

There are several technologies for the production of gaseous fuels by thermal processing. Based on our own experience in the gasification of various initial products, including manure and other agricultural waste, we proceed from the position that the power unit must use prepared fuel with stable characteristics in terms of moisture, energy indicators, and fractional composition. Only this approach allows to obtain stable performance of the energy complex. Suggested solutions include:

• drying bedding manure to a relative humidity of 20%;
• granulation of dried manure;
• gasification of fuel pellets;
• use of the resulting gaseous fuel for the production of heat and electricity;
• use of coke-ash residue for the production of fertilizers.

Consider the operation of a complex designed for the gasification of chicken manure for the conditions presented earlier:

• the capacity of the manure processing complex is 10 t/h (at a moisture content of 45%);
• drying manure to a relative humidity of 20%
• granulation, energy consumption — 100 kW/t of granules
• efficiency electric gas piston engines - 35%;
• production of thermal energy - up to 40% of the initial energy potential of the fuel;
• efficiency gas generator for generator gas - 75%;
• additional production of thermal energy 10%;
• efficiency drying complex 50%
• formation of coke-ash residue - up to 20%.

Analysis of the presented data:

• the specific heat of combustion of dry material is 4000 kcal/kg, which is justified in the case of using sawdust as a filler. The total heat of combustion of bedding manure at a moisture content of 20% will be:
  4000 ∙ (1 -0.2) - 550 ∙ 0.2 = 3090 kcal / kg

Humidity 20% corresponds to the content of 200 kg of water in 1 ton of manure. To obtain such a result, 312.5 kg of water must be removed from 1 ton of manure with a moisture content of 45%. As a result, out of 10 tons of manure with a moisture content of 45%, we get 6.875 tons of manure with a moisture content of 20%. The total amount of evaporated moisture will be 3125 kg.

• the energy potential of manure supplied for gasification will be:
  3090 ∙ 6875 = 21.2 Gcal
• energy potential of the gas obtained from the prepared manure:
  21.2 Gcal ∙ 0.75 = 15.9 Gcal (18.5 MW∙h)
• production of electrical energy using a reciprocating engine running on generator gas:
  18.5 MWh 0.35 = 6.48 MWh.
• additional heat generation:
  15.9 Gcal∙ 0.1+15.9 Gcal∙ 0.4 = 7.95 Gcal.
• production of coke-ash residue: 6.875 t ∙ 0.2 = 1.375 t/h

The residue, whose humidity is close to 0, and the content of minerals is higher than that of the original manure, is used as a filler in the production of composted fertilizers.

Energy costs for the operation of the complex:

• manure drying, providing removal of 3125 kg of moisture per hour. Thermal energy consumption:
  550 kcal / kg ∙ 3125 kg / 0.5 = 3.44 Gcal;
• production of granules to ensure the operation of the complex:
  6.875 t ∙ 100 kWh = 687.5 kWh.

Thus, the complex, designed for gasification of 10 t/h of bedding chicken manure with a moisture content of 45% and the production of electrical and thermal energy, minus energy for own needs, provides the generation of 6.48 - 0.6875 = 5.8 MW of electricity and 7.95 - 3.44 = 4.5 Gcal of thermal energy.

The gasification complex can provide the supply of gaseous fuel to ensure the operation of power equipment - boilers, furnaces, and other fuel-using units. Instead of reciprocating machines for the production of electrical energy, solutions involving the production and use of steam in turbogenerators or steam engines can also be used.

Features of the operation of the complex, including the gasification of prepared chicken manure, are as follows:

1. The technology involves the use of an inverted gasification process, in which gaseous products are formed in a reacting high-temperature zone. The operating temperature level of 1000….1200°C ensures reliable decomposition of hydrocarbon compounds into simple components. The composition of the gas produced from bedding manure filled with sawdust is presented in Table 1. As part of the study of the possibility of using prepared manure as a fuel, tests were also carried out on the gasification of granulated native manure, which showed that obtaining energy gas from it is possible only when the air blast is enriched with oxygen (Table 1).

Table 1. Composition of gas during gasification of pellets from manure

2. The gasification technology developed for the gasification of brown coal by the Sibtermo company (Krasnoyarsk) was used in waste processing. The operation of the generator is clear from the circuit diagram of the unit, which is shown in Fig.1. The generator is filled with fuel. The top layer of fuel is heated by electrical heating to the self-ignition temperature. Air is then fed into the generator from below. As a result, the reaction layer heats up and the gasification process begins. During the operation of the generator, the reacting layer moves down, and a layer of coke-ash residue is formed above it, in which additional gas purification takes place. Organization of operation of the generator with low speeds of movement of gases in the internal space provides a long time of stay of gasification products in the zone of high temperatures and low removal of ash particles. The operating time of the generator on one load is at least 9 hours. At the end of the process, the air supply stops, the generator cools down, the coke-ash residue is unloaded, and the working cycle is repeated. The operation of the complex with an installed capacity of 2 MW for generator gas (Fig. 2) confirmed the reliability of the equipment and its high economic performance. The automatic control system allows you to track all important events during the operation of the complex, quickly manage the technological process and save the values ​​of important parameters (Fig. 3.). The complex for ensuring operation is made of three gas generators of the same type, the alternating operation of which ensures the operation of the rest of the equipment of the complex in a continuous mode.

3. The resulting gas is subjected to cooling, purification and can be used in power units. At the same time, environmental indicators during its use correspond to the emission of pollutants during the operation of power units on natural gas.

Fig.1. Schematic diagram of a batch gas generator
Designations:

- fuel reserve layer;

- a layer of heating, oxidation and reduction;

— layer of coke-ash residue;

is the direction of gas flow.

The technology for high-quality purification of generator gas, as well as equipment for the production of electric and thermal energy from it using internal combustion engines, was developed by Adaptika LLC. The first of the launched units, with an installed capacity of 100 kW for electric energy, using generator gas produced from wood waste as fuel, has worked for more than 2 years, which confirms the reliability of the created complex. A technological chain for processing woodworking waste into electrical and thermal energy has been developed, and serial production of power generating complexes has been established. The next obvious step was the decision to dispose of agricultural waste, one of which is the processing of bedding manure. Specific capital costs for the creation of the complex do not exceed 2000 Euro per 1 kW of installed electric power.

Fig.2. The operating complex for gasification of bio-raw materials with a capacity of 2 MW.

Fig.3. Mnemonic diagram of the complex for the production and use of generator gas.

Comparison of the results of the analysis carried out for the technologies under consideration shows the superiority of the gasification technology in terms of the energy efficiency of the use of manure, the comparative simplicity of the scheme for the production and use of generator gas. Capital costs for the creation of gasification complexes and the use of generator gas are comparable to the costs for other technologies.

The above materials show that a comprehensive approach to the disposal of chicken manure is the most effective. The production of energy in excess of one's own needs, as well as the production of fertilizers for use in one's own fields, significantly increase the efficiency and economy of the enterprise as a whole. The following production structure is assumed (Fig. 4):

The complex is designed for the production of fertilizers from composted chicken manure, fuel pellets, granulated feed additives and heat and electricity. It is advisable to select the capacities of the units with a certain margin, which ensures the flexible use of the entire complex with the predominant production of the most profitable type of product in a given period.