Laboratory unit for anaerobic digestion of litterless poultry manure

Abstract

FIELD: agriculture.SUBSTANCE: laboratory unit for anaerobic processing of litterless poultry manure consists of a digester, a tank for homogenization with water, an adaptation unit, a dry gas holder, a filter housing with natural zeolite for cleaning biogas with lower and upper mesh partitions, gas inlet and outlet fittings, a high-pressure compressor, a gas cylinder, and it additionally comprises an adsorber, a natural zeolite regeneration unit, a mixing tank with mixing blades, whereas the adsorber is made of a rectangular shape with an opening side cover and is located between the gas holder and the natural zeolite filter housing, mesh cassettes with synthetic zeolite are installed inside it, whereas the upper cassette is filled with type NaA, the middle cassette is filled with type NaX, the lower cassette is filled with type CaA with a particle size of 0.5-1.0 mm and each cassette is filled by 90-95% with the corresponding synthetic zeolite, a natural regeneration, the zeolite unit is located above the mixing tank, under which a receiving tank is installed, the inter-structural connections are made using pipelines with shut-off valves, natural zeolite is used with a fraction size of 1.2-3.0 mm.EFFECT: making biogas and organo-mineral fertilizer from litter-free poultry manure.2 cl, 1 dwg, 1 ex

Description

[0001] The invention relates to agriculture, in particular to the field of biotechnology for processing litterless poultry manure.

[0002] A device is known for implementing a method for processing organic substrates into biogas, liquid and solid fertilizers and industrial water, consisting of a hydraulically connected equalizer, an anaerobic bioreactor, a mechanical thickener, the output of which for the solid fraction is connected to the solid fertilizer preparation unit, the output for the liquid fraction is connected to the liquid fraction deammonization unit, while an aerobic bioreactor is additionally provided, a preliminary mechanical thickener, placed between the equalizer and the anaerobic bioreactor, a section for aerobic processing of the liquid fraction, the output of the solid fraction of the preliminary mechanical thickener is connected to the fertilizer preparation unit, the output of the liquid fraction of the additional mechanical thickener is connected to the inlet of the anaerobic bioreactor, the output of the liquid fraction deammonization unit is connected to the inlet of the section for aerobic processing of the liquid fraction,The anaerobic and aerobic bioreactors and the section for aerobic treatment of the liquid fraction are designed as a sectioned monoblock apparatus with an isothermal thermal connection between them. The outlet of the aerobic bioreactor for oxygen-containing gas is sequentially connected through a thermal compressor to the section for aerobic treatment of the liquid fraction, an equalizer, and a liquid fraction deammonization unit. (Patent of the Russian Federation No. 2542108, published on February 20, 2015),

[0003] A manure utilization line is known for producing biogas and fertilizers, consisting of a hydraulically connected manure receiver, an anaerobic bioreactor with a heat exchanger-condenser of a heat pump, an additional anaerobic bioreactor with a heat exchanger, a settling tank-storage tank for fertilizers with a heat exchanger-evaporator of a heat pump, wherein the heat exchanger-condenser and the heat exchanger-evaporator are connected to each other by means of a compressor with a gas motor drive on biogas to form a thermodynamic circuit of the heat pump, the heat exchanger-condenser of the heat pump is made in the form of a vertical pipe with hollow walls and is placed coaxially inside the anaerobic bioreactor, the heat exchanger-evaporator of the heat pump is made in the form of a submersible coil and is placed in the lower part of the settling tank-storage tank for fertilizers,The heat exchanger of the additional anaerobic bioreactor utilizes the thermal energy of the coolant and the exhaust gases from the gas-motor drive of the heat pump compressor. The manure receiver also includes an additional heat exchanger-condenser of the heat pump. The upper part of the settling tank-accumulator also includes an additional heat exchanger-evaporator of the heat pump, designed as a vertical pipe with hollow walls. The heat exchanger of the additional bioreactor is designed similarly to the heat exchanger-condenser and is connected to the gas-motor drive of the heat pump compressor via a coolant circulation line with a three-way control valve, the heat-sensing element of which is located in the working space of the additional bioreactor. Mesophilic (32°C≤t≤37°C) and thermophilic (52°C≤t≤57°C) temperature regimes, respectively, are maintained in the first and second anaerobic bioreactors. (Patent of the Russian Federation No. 2577166, published on March 10, 2016),

[0004] A line for manure utilization with the production of biogas and fertilizers is known, consisting of a manure receiver, an anaerobic bioreactor, a pump, a heat exchanger-condenser of a heat pump, connected in a single circulation circuit, a settling tank-storage of fertilizers with a heat exchanger-evaporator of a heat pump, and the heat exchangers are connected to each other by means of a compressor with a gas motor drive on biogas with the formation of a thermodynamic circuit of the heat pump, wherein the heat exchanger-condenser of the heat pump is made in the form of a vertical pipe with hollow walls and is placed coaxially inside the anaerobic bioreactor, the heat exchanger-evaporator of the heat pump is made in the form of a submersible coil and is placed in the lower part of the settling tank-storage of fertilizers, and between the anaerobic bioreactor and the settling tank-storage of fertilizers at least one additional bioreactor is installed with a pump and a heat exchanger made similar to a heat exchanger-condenser,which utilizes the thermal energy of the coolant and exhaust gases of the gas engine drive of the heat pump compressor. (Patent of the Russian Federation No. 2414443, published March 20, 2011),

[0005] A laboratory-scale unit for anaerobic digestion of non-litter cattle manure was selected as a prototype. It consists of a methane tank, a tank for homogenizing native manure with water, an adaptation unit, a dry gas holder, a filter for cleaning biogas, a high-pressure compressor, and a gas cylinder. (http: / / elib.altsfa.ru / disser / 2018 / Avtoreferat-Semenova.pdf) p. 13. The biogas purification filter consists of a filter housing, natural zeolite, a lower mesh partition, an upper mesh partition, a gas inlet fitting, and a gas outlet fitting. (http: / / elib.altstu.ru / disser / 2018 / Avtoreferat-Semenova.pdf) p. 10.

[0006] Common disadvantages of known devices are the low degree of purification of the emitted biogas and the lack of means for mixing adsorbents with litter-free poultry manure.

[0007] The task is to develop a laboratory installation for anaerobic processing of litter-free poultry manure.

[0008] Technical result - obtaining biogas and organo-mineral fertilizer from litterless poultry manure.

[0009] The technical result is achieved by a laboratory installation for anaerobic processing of litterless poultry manure, consisting of a digester, a tank for homogenization with water, an adaptation unit, a dry gas holder, a filter housing with natural zeolite for cleaning biogas with lower and upper mesh partitions, gas inlet and outlet fittings, a high-pressure compressor, a gas cylinder, which additionally contains an adsorber, a natural zeolite regeneration unit, a mixing tank with mixing blades, while the adsorber is made of a rectangular shape with an opening side cover and is located between the gas holder and the natural zeolite filter housing, mesh cassettes with synthetic zeolite are installed inside it, while the upper cassette is filled with type NaA, the middle cassette is filled with type NaX, the lower cassette is filled with type CaA with a particle size of 0.5-1.0 mm and filling each cassette with 90-95% corresponding synthetic zeolite,The natural zeolite regeneration unit is located above the mixing tank, beneath which is a receiving tank. Interconnections between structures are made using pipelines with shut-off valves. Natural zeolite is used with a particle size of 1.2-3.0 mm. The mesh size in the mesh cassettes is smaller than the particle size of synthetic zeolite.

[0010] The invention is explained by a circuit diagram, which consists of:

[0011] 1 - digester

[0012] 2 - homogenization containers

[0013] 3 - adaptation installation

[0014] 4 - dry gas holder

[0015] 5 - filter with natural zeolite

[0016] 6 - High pressure compressor

[0017] 7 - gas cylinder

[0018] 8 - Bottom mesh partition

[0019] 9 - Upper mesh partition

[0020] 10 - gas inlet / outlet fittings

[0021] 11 - adsorber

[0022] 12 - Natural zeolite regeneration unit

[0023] 13 - receiving container

[0024] 14 - Mixing container with mixing blades 15

[0025] 16 - mesh cassettes

[0026] 17 - pipeline connections with shut-off valves 18.

[0027] Litterless chicken manure is a sticky, greasy substance with an unpleasant odor. It is characterized by higher moisture content and increased nitrogen content. Some characteristics of litterless manure: at 64% moisture content, it contains 2.1% nitrogen, including 0.52% in the form of ammonia, 1.44% phosphorus, and 0.64% potassium.

[0028] Natural zeolites are known to be minerals from the group of hydrous aluminosilicates of alkali and alkaline earth elements of volcanic-sedimentary origin with a tetrahedral structural framework. Natural zeolite is a microporous crystalline "sponge," the pore volume of which accounts for up to 50% of the zeolite framework volume, making it a highly active adsorbent. Therefore, when natural zeolite is mixed with chicken manure, it undergoes modification, filling its internal cavities with the nutritional properties of the chicken manure. Natural zeolite also aerates the soil (prevents soil from clumping) and has prolonging properties (gradually releasing accumulated nutrients back into the soil).

[0029] The use of natural zeolite with fraction sizes of 1.2-3.0 mm ensures good bulk density in the filter itself, and also has a good effect on its introduction into the soil both as a soil aerator and as a fertilizer - prolonging the nutritional properties of chicken manure.

[0030] Biogas is produced by fermenting biomass (agricultural waste, municipal solid waste, sewage). The gas emerges in a water-saturated state. As a result of this process, biogas is saturated with water vapor and contains, in addition to methane (CH4), carbon dioxide (CO2) and a significant amount of hydrogen sulfide (H2S).

[0031] Removing ballast impurities increases the calorific value of biogas, which has a positive effect on extending the life of pipelines (preventing their corrosion) and gas supply system equipment.

[0032] In general, biogas is considered as an unrefined complex of gaseous and aerosol components that arises as a result of the process (rotting) of bacterial decomposition of biomass - a complex organic conglomerate of plant and animal proteins, amino acids and other compounds containing carbon.

[0033] The absorption of ballast gases takes place in an adsorber with synthetic natural zeolite, through which biogas is passed and - by repeatedly coming into contact with the large surface of synthetic zeolite granules - “loses” unwanted impurities in the active interphase layer.

[0034] The particle size of synthetic zeolite is 0.5-1.0 mm, which ensures dense bulk capacity inside the cassettes, thereby ensuring the stage-by-stage maximum purification of biogas from impurities.

[0035] Filling the cassette to 90-95% provides a dense bulk surface, and when removing the cassette, it ensures easy removal of the spent synthetic zeolite from it and filling it with new one.

[0036] During the cleaning process, the micropores of the synthetic zeolite granules become clogged, so after a certain time it needs to be replaced or regenerated.

[0037] The adsorber is designed with an opening side cover, inside which three removable filter cartridges are located sequentially from top to bottom, making it possible to quickly and easily replace used filter material (synthetic zeolites) with new ones.

[0038] Filling the upper cassette with NaA zeolite ensures the absorption of water vapor from biogas.

[0039] Filling the middle cassette with NaX zeolite ensures the absorption of water vapor and methane from biogas.

[0040] Filling the lower cassette with CaA zeolite ensures the absorption of hydrogen sulfide and carbon dioxide vapors from biogas.

[0041] Three-stage biogas purification in the adsorber allows the almost purified biogas to enter a filter with natural zeolite, where it undergoes additional purification. Therefore, the accumulation of waste impurities in the natural zeolite is minimal.

[0042] Waste natural zeolite is purified in the regeneration unit, which is designed to restore the original technological parameters of the zeolite.

[0043] The regeneration unit can be selected from any of the known options, based on the manufacturer's capabilities. This could include hot air drying, salt water rinsing, etc.

[0044] In a mixing tank, purified zeolite is mixed with poultry manure, where it is infused with nutrients and prolongs the action of these substances in the soil. In other words, by mixing and blending a natural mineral—natural zeolite—with an organic fertilizer—non-litter poultry manure, an organo-mineral fertilizer is produced.

[0045] Example of specific implementation.

[0046] Bird droppings were fed from the homogenization tank 2 to the methane tank 1, the starter was fed from the adaptation unit 3 and the process of anaerobic fermentation of the bird droppings was carried out for 25 days at a temperature of 25-27°C (the known time and temperature of the fermentation process).

[0047] The resulting gas from digester 1 entered gas holder 4 via pipeline 17, from where it entered adsorber 11, where it underwent three-stage purification with synthetic zeolites. Afterward, the purified gas underwent final purification in filter 5 with natural zeolite. The biogas was then fed by compressor 6 to gas cylinder 7. The methane concentration in the resulting biogas was 59.03%.

[0048] The spent natural zeolite entered the regeneration unit 12, where in our case it was washed and blown with hot air, and the purified natural zeolite was fed into the tank 14, where the bird droppings from the digester 1 flowed through the pipeline 17. The natural zeolite and the litter-free bird droppings were mixed manually by means of the blades 15.

[0049] In mixing tank 14, the internal cavities of natural zeolite were filled with micro- and macronutrients from bird droppings. The finished product was characterized as an organo-mineral fertilizer.

[0050] When the prepared mixture was added to the soil, natural zeolite prolonged the nutrient components, thereby improving the soil characteristics both as an aerator and as an adsorbent.

[0051] The spent synthetic zeolite was recovered by any known method and reused by pouring it into cassettes.

[0052] Thus, the laboratory installation for anaerobic processing of litterless poultry manure ensures the production of biogas and organo-mineral fertilizer from litterless poultry manure.

Claims

1. A laboratory unit for anaerobic processing of litterless poultry manure, consisting of a digester, a tank for homogenization with water, an adaptation unit, a dry gas holder, a filter housing with natural zeolite for cleaning biogas with lower and upper mesh partitions, gas inlet and outlet fittings, a high-pressure compressor, a gas cylinder, characterized in that it additionally contains an adsorber, a natural zeolite regeneration unit, a mixing tank with mixing blades, wherein the adsorber is made of a rectangular shape with an opening side cover and is located between the gas holder and the natural zeolite filter housing, mesh cassettes with synthetic zeolite are installed inside it, wherein the upper cassette is filled with type NaA, the middle cassette is filled with type NaX, the lower cassette is filled with type CaA with a particle size of 0.5-1.0 mm and each cassette is filled by 90-95% with the corresponding synthetic zeolite,The natural zeolite regeneration unit is located above the mixing tank, under which a receiving tank is installed, the inter-structural connections are made by pipelines with shut-off valves, natural zeolite is used with a fraction size of 1.2-3.0 mm.

2. A laboratory setup according to paragraph 1, characterized in that the size of the cells in the mesh cassettes is smaller than the size of the synthetic zeolite particles.

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