CN101338273A - Home device and method for producing methane by dry-type fermentation of stalks - Google Patents

Abstract

The invention relates to a device for producing biogas by straw dry type fermentation and a method, belongs to the agriculture environmental protection and biomass energy source utilization field. The straw is chopped. Nitrogen fertilizers are added. C/N is adjusted. The mixture is arranged in a column shaped biogas digester built underground after the mixture is composted. Anaerobic fermentation outcomes are inoculated and sealed with red-sludge plastic. The biogas is produced in the process of anaerobic fermentation. When the biogas production is lowered, the straw is processed eluviation by biogas liquid which is pumped by manual pumping device. When the biogas production is obviously reduced, the new materials should be changed. The straw dry typed anaerobic biogas can be realized. The technical requirements that the straw is substituted the animal manure as the main raw materials are achieved. The straw dry typed fermentation technology is used, which can reduce the difficulties in treating biogas liquid and biogas slag of the wet typed anaerobic fermentation biogas. At the same time, the volumetric biogas production of the biogas digester is improved, and the biogas digester building cost is lowered and the biogas digester occupied area is reduced. The designed biogas fluid backflow system solves the difficulty of the exchange of mass flows and substances in the straw dry typed fermentation.

Description

The device and method of home straw producing methane by dry-type fermentation

Technical field:

The present invention relates to a kind of device and method of home straw producing methane by dry-type fermentation, is a kind of technology of utilizing of stalk energy, belongs to agriculture environmental protection and Biomass Energy Utilization field.

Background technology:

The stalk resource in China rural area is very abundant, and only important crop material just has nearly 20 kinds at present, and output is huge.It is estimated that the annual all kinds of agricultural crop straw generations of China reach 700,000,000 t, this wherein 42% directly or cross also field of abdomen, 30% as agricultural fuel, 8% as industry or other purposes, 20% about 1.2 hundred million tons of residues are not utilized].These remaining agricultural crop straws go out of use in the field, room, threshing ground head, not only account for and pressed a large amount of soils, influenced rural environmental hygiene, particularly in " three summer jobs ", " three autumn jobs as harvesting, tilling and planting " season in every year, the peasant directly burns these residue stalk overwhelming majority in the field in order to rush-harvest and rush-plant then, the open incineration of a large amount of residue stalks not only causes the great wasting of resources, and bring serious topsoil, even influence the safety of the Normal Take-Off And Landing and the running car of aircraft, and frequent initiation fire accident.

And meanwhile, global energy dilemma increases the weight of day by day, demands developing the novel energy of alternative oil, coal, particularly renewable energy source urgently, and biomass energy more receives the great attention and the concern of countries in the world as a kind of reproducible clean energy.Agricultural crop straw is as the waste that is produced in grain or the fodder production; be mainly carbon compound; as energy utilization; enormous amount and renewable not only; thereby exploitation agricultural crop straw recovery energy approach; not only can solve a large amount of stalks and abandon and the environmental pollution and the financial loss problem of generation, and can slow down the world energy sources crisis, especially can solve the difficult problem of urban residents' power supply of huge numbers of families.

For solving Chinese huge numbers of families urban residents, particularly sparsely populated again away from the urban residents' in city or market town clean energy supply bottleneck, the country from last century the seventies begin, just promote the use of with feces of livestock and poultry and human excrement etc. and be the methane-generating pit technology of main substrate, obtained good effect in the rural area.Yet; in recent years along with aquaculture after the development of mass-producing sub-district; the rely raw material-feces of livestock and poultry of aerogenesis of methane-generating pit for farm household is less and less; methane-generating pit is faced with does not have the potable condition of rice, the exploratory development domestic methane tank substitute feces of livestock and poultry raw material technology more and more urgently, more and more important.

Utilize research and the demonstration work of agricultural crop straw as the domestic methane tank raw material, can trace back to the eighties in last century, promptly utilize existing hydraulic type biomass pool, stalk mixed with ight soil carry out producing methane through anaerobic fermentation, its technology exists the stalk come-up, and formation is crusted and influenced aerogenesis easily, and after fermentation ends, natural pond slag and natural pond liquid difficult treatment, particularly dense waterway net region.

Publication number is the patent of CN101020912, a kind of method of the stalk mixing fermentation of methane bacterium refluxing and pulverizing being produced biogas is provided, it is characterized in that, it is that raw material agricultural crop straw with fermentation methane is ground into stalk powder, stalk particle, behind the stalk silk, reenter marsh-gas fermentation tank, marsh-gas fermentation tank bottom discharge pipe is discharged contains the methanobacteria slag charge, contained methanobacteria quantity according to practical measurement, by containing methanobacteria slag charge and the new volume ratio that drops into stalk is to be input to the marsh-gas fermentation tank production biogas that continuously ferments after 0.5～8.0: 1.0 the mixed, remainder contains the methanobacteria slag charge and is discharged into the slag charge pond, this patent only relates to natural pond liquid backflow inoculation, and biogas residue and biogas liquid is discharged by discharge nozzle, easy ingress of air, influence the quantity of anerobe, and need before the inoculation measuring contained methanobacteria quantity, difficulty or ease operation in the practical application of rural area peasant household.

Publication number is the patent of CN1769220, providing a kind of is the biogas production technology of raw material with kitchen excess, stalk, feces of livestock and poultry and active sludge, relate to biogas production gordian technique and high solid substance biogas fermentation reactor technology, but what this patent was related is the wet method anaerobic fermentation technology, and does not fit into the use of rural area peasant household.

Publication number is the patent of CN1403396, provides a kind of period stimulating stalk and municipal wastes to carry out the method for solid state fermentation biogas.It is characterized in that putting into the solid state fermentation tank body after the quick-fried processing of organic waste process vapour with air-dry stalk or screening; Then gas-explosive material is mixed rapidly with biogas, be sealed in the fermentation tank body and carry out solid state fermentation; Feed the air in the biogas emptying tank body that ferments, adopt the speed of extraneous cycle pressure variation with strengthening solid state fermentation; Rapid exhaust gas collection biogas, this method and technology requires high, and facility investment is big, is not suitable for the rural area and uses.

Publication number is the patent of CN2863807, provide a kind of and novelly exempted from clearly that stalk ight soil comprehensively uses thermal insulation methane pool, the technical field of building that relates to methane-generating pit, major technique is characterised in that water pressure house and feed-pipe and is one that the fermentation material enters opening for feed (between setting-out) and enters the methane-generating pit fermentation through soaking automatically after acid is produced in liquefaction.Being provided with discharge nozzle in the methane-generating pit utilizes the inside aerogenesis pressure of methane-generating pit the natural pond slag can be extruded flow direction collected manure hole from discharge nozzle.And need not manually clear pond.And the broken shell microgas is housed in methane-generating pit inside.Make methane-generating pit more convenient in daily administration, improve factor of created gase, aerogenesis is stable.This technology and what relate to is a kind of wet method anaerobic methane production gas technology, and because of stalk be floating matter by being difficult to enter digester between setting-out, technical infeasible.

In sum, existing patented technology is difficult to solve the technical barrier of stalk dry method fermentation, and described technology or to invest big cost high or be not suitable for rural area peasant household and use, and is difficult to apply.

Summary of the invention:

Technical problem the objective of the invention is to: produce the natural pond liquid difficult treatment that biogas exists at dense waterway net region at the family of now applying with hydraulic type methane tank straw wet method, with the stalk is that main raw material is after the hydraulic type biomass pool fermentation ends, stalk residue cleaning inconvenience, existing hydraulic type biomass pool does not have natural pond liquid return-flow system, can't carry out natural pond liquid and return difficulties such as liquid, a kind of new pond type and method of home straw dry method anaerobic methane production gas is provided.

The object of the present invention is achieved like this for technical scheme:

1, the device of the dried fermentation methane production of a kind of home straw, it is characterized in that: methane-generating pit (1) is to infuse or concrete casting and waterproof pond with brick, methane-generating pit is as cylinder shape, the bottom, pond is downward taper shape, with cylindrical junction a porous backing plate (2) is arranged conical, the pipeline (3) that is connected to the methane-generating pit outside is arranged at the bottom of conical awl, pipeline links to each other with the collecting tank of building methane-generating pit one side in (4), the water that is come out by the methane-generating pit leaching can be arranged into collecting tank by pipeline (3), this collecting tank is lower than methane-generating pit, there is vertical shaft (5) the collecting tank top, one pumping plant (6) is installed in vertical shaft, natural pond liquid in the collecting tank can be extracted in the methane-generating pit with plastics tubing (7) by refluxing, form natural pond liquid return-flow system, but the lid (8) that a water seal is arranged on the top of methane-generating pit has biogas to portal (9) on the lid, portals and biogas that methane-generating pit produces can be introduced methane cooker by this, biogas lamp.

2, a kind of method of home straw producing methane by dry-type fermentation, it is characterized in that: with straw chopping, add nitrogen manure, regulate C/N, add promptly in the fertilizer in the nitrogen and stalk that the ratio of carbon content is 1: 25 in the nitrogen content summation and stalk, mix laggard windrow corruption, stalk that will be after piling corruption, put into and be built in subterranean above-mentioned cylinder shape methane-generating pit, inoculation anaerobically fermenting product, fermentation raw material weight is 1 with the ratio of inoculum weight: 0.3-0.4, the limit adds the stalk limit and adds the anaerobically fermenting product, seal with red-sludge plastic, carry out producing methane through anaerobic fermentation, when gas production rate reduces, utilize the manual pumping device to extract natural pond liquid stalk is carried out leaching, when gas production rate is improved, in time change virgin material.

Described chopping is meant that artificial or machinery shreds below the 10cm with stalk, and described nitrogen manure is meant nitrogenous chemical fertilizer, as urea, ammonium sulfate, phosphorus ammonium or carbon ammonium; Described heap is rotten to be meant chopping and the stalk after regulating C/N, by stalk heavy with the water anharmonic ratio be 1: 2.5-3.5, water drenches behind the stalk the above height of composting 50cm and covers with plastic cloth or other material that can reduce moisture loss, and the heap temperature reaches more than 45 ℃ composting 3-6 days; Described stalk is meant corn, straw, wheat straw or herbage; Described anaerobically fermenting product is meant mud, biogas residue and biogas liquid, cow dung or pond sludge.

Described replacing virgin material takes out the residual body of stalk after being meant methane tank cover being opened from methane-generating pit, add the stalk through anticipating, and simultaneously, liquid natural pond, the natural pond slag that extracts from water collecting basin is inoculated initiate raw material as inoculum.

Beneficial effect technology indicators of overall performance of the present invention is with the advantage of similar technology comparison: it can realize stalk dry type anaerobic methane production gas, having reached basic substituting with the feces of livestock and poultry is the technical requirements that main raw material produces biogas, the straw by dry fermentation technology that adopts, can reduce the difficulty that liquid natural pond, natural pond slag is handled in the wet type producing methane through anaerobic fermentation, the methane-generating pit volume yield rate is improved, reduced the methane-generating pit construction cost and reduced the methane-generating pit floor space.The natural pond liquid return-flow system of design has solved the difficulty of matter stream and material in the fermentation of stalk dry method.

Description of drawings

Fig. 1 produces the firedamp gas equipment structure iron

1 methane-generating pit; 2 porous backing plates; 3 pipelines; 4 collecting tanks; 5 vertical shafts; 6 pumping plants; 7 reflux uses plastics tubing; 8 lids; 9 biogas portal

Embodiment

With a three-person household is example, cooks and heats up water the needs of biogas amount, design and construction a bite 6m by technical feature and this resident of stalk producing methane by using dry anaerobic digestion ³Methane-generating pit (schema sees accompanying drawing 1 for details).Methane-generating pit 1 is to infuse or concrete casting and waterproof pond with brick, methane-generating pit is as cylinder shape, the bottom, pond is downward taper shape, with cylindrical junction a porous backing plate 2 is arranged conical, the pipeline 3 that is connected to the methane-generating pit outside is arranged at the bottom of conical awl, pipeline links to each other with the collecting tank 4 of building methane-generating pit one side in, the water that is come out by the methane-generating pit leaching can be arranged into collecting tank by pipeline 3, this collecting tank is lower than methane-generating pit, there is vertical shaft 5 the collecting tank top, one pumping plant 6 is installed in vertical shaft, natural pond liquid in the collecting tank can be extracted in the methane-generating pit with plastics tubing 7 by refluxing, form natural pond liquid return-flow system, but the lid 8 of a water seal is arranged on the top of methane-generating pit, there is biogas to portal 9 on the lid, portals and biogas that methane-generating pit produces can be introduced methane cooker by this, biogas lamp.

Claim 2.0-2.5 ton straw, straw is shredded to 10cm, stalk is drenched with about 6-7 ton water, add about 50 kilograms of urea then, mix, composting becomes 1.5 meters high heaps, cover with plastics film, the heap temperature reached more than 45 ℃ composting 4 days, spread out, air-dry half a day, put into the methane-generating pit of building up then, during charging for the first time, make inoculum with about 500 kilograms of natural pond slags, the limit adds straw, and the limit adds the natural pond slag, after having piled, carry out leaching with about 200 kilograms of natural pond liquid again, the water outlet that refluxes with plastics tubing and pumping plant is connected, build lid and seal, get final product, after fermenting about one month, the natural pond liquid that extracts in the water collecting basin with pumping plant returns liquid, returns about one hour of liquid time.So repeatedly, continue about half a year, the methane tank gas production amount obviously descends, promptly open methane tank cover, instrument with the band claw takes out the stalk residue, the stalk that to pile in advance then after the corruption joins in the methane-generating pit again, directly extracts natural pond liquid as inoculum with pumping plant, seals then and carries out producing methane through anaerobic fermentation.

Claims (4)

1, the device of the dried fermentation methane production of a kind of home straw, it is characterized in that: methane-generating pit (1) is to infuse or concrete casting and waterproof pond with brick, methane-generating pit is as cylinder shape, the bottom, pond is downward taper shape, with cylindrical junction a porous backing plate (2) is arranged conical, the pipeline (3) that is connected to the methane-generating pit outside is arranged at the bottom of conical awl, pipeline links to each other with the collecting tank of building methane-generating pit one side in (4), the water that is come out by the methane-generating pit leaching can be arranged into collecting tank by pipeline (3), this collecting tank is lower than methane-generating pit, there is vertical shaft (5) the collecting tank top, one pumping plant (6) is installed in vertical shaft, natural pond liquid in the collecting tank can be extracted in the methane-generating pit with plastics tubing (7) by refluxing, form natural pond liquid return-flow system, but the lid (8) that a water seal is arranged on the top of methane-generating pit has biogas to portal (9) on the lid, portals and biogas that methane-generating pit produces can be introduced methane cooker by this, biogas lamp.

2, a kind of method of home straw producing methane by dry-type fermentation, it is characterized in that: with straw chopping, add nitrogen manure, regulate C/N, add promptly in the fertilizer in the nitrogen and stalk that the ratio of carbon content is 1: 25 in the nitrogen content summation and stalk, mix laggard windrow corruption, stalk that will be after piling corruption, put into the cylinder shape methane-generating pit that is built in the described device of subterranean claim 1, inoculation anaerobically fermenting product, fermentation raw material weight is 1 with the ratio of inoculum weight: 0.3-0.4, the limit adds the stalk limit and adds the anaerobically fermenting product, seal with red-sludge plastic, carry out producing methane through anaerobic fermentation, when gas production rate reduces, utilize the manual pumping device to extract natural pond liquid stalk is carried out leaching, when gas production rate is improved, in time change virgin material.

3, according to the method for the dried fermentation methane production of right 2 described a kind of home straws, it is characterized in that: described chopping is meant that artificial or machinery shreds below the 10cm with stalk, described nitrogen manure is meant nitrogenous chemical fertilizer, as urea, ammonium sulfate, phosphorus ammonium or carbon ammonium; Described heap is rotten to be meant chopping and the stalk after regulating C/N, by stalk heavy with the water anharmonic ratio be 1: 2.5-3.5, water drenches behind the stalk the above height of composting 50cm and covers with plastic cloth or other material that can reduce moisture loss, and the heap temperature reaches more than 45 ℃ composting 3-6 days; Described stalk is meant corn, straw, wheat straw or herbage; Described anaerobically fermenting product is meant mud, biogas residue and biogas liquid, cow dung or pond sludge.

4, according to the method for claim 2 or the dried fermentation methane production of 3 described a kind of home straws, it is characterized in that: after described replacing virgin material is meant methane tank cover opened, the residual body of stalk is taken out from methane-generating pit, the stalk of adding through anticipating, simultaneously, liquid natural pond, the natural pond slag that extracts from water collecting basin is inoculated initiate raw material as inoculum.