JP2007090340A - Batch biogas fermentation apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a batch biogas fermentation apparatus which allows a carry-in vehicle to be driven easily when organic waste is carried in and is designed with a high degree of freedom and the installation location of which is hardly affected by the surrounding environment. <P>SOLUTION: The biogas fermentation apparatus is constituted so that a spray nozzle 22 is arranged in the space above an airtight fermentation chamber 1 and a methanogen-containing liquid is sprayed on organic waste 10, which is thrown on a bed surface 8a of the fermentation chamber 1, from the spray nozzle 22 to decompose organic waste 10 by methanogen and to generate biogas. The bed surface 8a of the fermentation chamber 1 is formed flatly. A groove 11 for recovering the methanogen-containing liquid is formed on the bed surface 8a. A groove 13 for discharging the methanogen-containing liquid, which communicates with the groove 11 for recovering the methanogen-containing liquid, is formed at one side edge of the bed surface 8a. A methanogen-containing liquid storage tank is arranged for recovering/storing the methanogen-containing liquid which is recovered in the groove 11 for recovering the methanogen-containing liquid and discharged to the outside of the fermentation chamber 1 through the groove 13 for discharging the methanogen-containing liquid. The methanogen-containing liquid in the methanogen-containing liquid storage tank is supplied to the spray nozzle 22. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a batch-type biogas fermentation apparatus utilizing decomposition of organic waste by methane fermentation.

  Conventionally, composting (ie, production of organic fertilizer) to effectively use organic waste such as human waste, septic tank sludge, sewage treatment sludge, livestock manure, marine waste, pruned branches, weeded products and garbage Is being considered. The above composting is to treat a suitable organic waste among the organic waste by aerobic fermentation, and the aerobic fermentation supplies air to the organic waste and decomposes the organic matter by aerobic bacteria. It is something to make. However, in aerobic fermentation, a large amount of sawdust is required for moisture adjustment, and stirring power is required to promote aerobic fermentation. Heating energy is also required, which can be said to be an energy-intensive processing method. Furthermore, many organic wastes emit a foul odor such as ammonia, and there is a problem of air pollution such as ammonia evaporation.

  Therefore, an anaerobic fermentation process that is performed by blocking the processed material from the atmosphere has attracted attention. According to this anaerobic fermentation, organic waste is decomposed by methane-fermenting bacteria (hereinafter referred to as “methane bacteria”) to generate biogas (mainly methane gas), and the generated biogas is effectively utilized. In addition to recovering energy, the digestive juice after fermentation is also useful as a good liquid fertilizer. Moreover, generation | occurrence | production of a bad odor and transpiration of a noxious gas component can be eliminated by interrupting | blocking a processed material from air | atmosphere. Many of the anaerobic fermentations that have been developed so far are generally treated in a slurry state in which the amount of water in the organic waste is 85% or more, which is generally called wet treatment. Therefore, nearly 90% of the wet processing is moisture not to be treated, and power and large capacity equipment for transferring and storing the moisture are required. In addition, in wet processing, it is necessary to adjust the amount of water to make a slurry, and in order to dispose of the processing liquid after fermentation processing, wastewater treatment equipment that discharges the processing liquid to rivers, etc. A storage facility such as a large slurry tank is required. Moreover, in a fermenter, the power for stirring is required in order to promote fermentation efficiency, and troubles, such as a suspended | floating matter and a sediment, are easy to occur. Furthermore, although the fire extinguishing liquid is an effective liquid fertilizer, since it is almost the same amount as the processing amount, securing farmland for spraying becomes a problem.

  On the other hand, a treatment method called dry methane fermentation treatment has been proposed. In this method, since the amount of water in the organic waste to be treated is as small as 60 to 85%, the solid matter after treatment can be used as it is or as a fertilizer after aerobic treatment. And storage facilities are not required, and the scale can be reduced. Moreover, in wet processing, in order to keep fermentation efficiency high, the maintenance of a fermenter is an important factor, but in dry methane fermentation processing, it can be made almost maintenance-free. Such dry methane fermentation treatment includes a continuous type and a batch type. In the case of the continuous type, processing is mainly for garbage disposal, and the processed product is almost solid, so that it is difficult to handle, and clogging problems and power for handling are required.

On the other hand, in the batch type, a garage type biogas fermenter as shown in FIG. 6 has been proposed (for example, see Patent Document 1). This garage-type biogas fermenter has left and right lateral walls 51 (only one lateral wall 51 is shown in the figure) and a front wall 52 (a door 52b is attached to a loading / unloading port 52a formed on the front wall 52). ), A back wall 53, a ceiling wall 54 (all of these walls 51 to 54 are made of concrete) and a floor 55, and fermentation biomass is placed in a space surrounded by the walls 51 to 54 and the floor 55. 56 is charged in a batch. The floor surface 55a of the floor 55 is inclined downwardly from the front wall 52 toward the back wall 53, and at the central portion (that is, the central portion in the left-right direction) between the lateral walls 51. Inclined downward in a downward direction. A drain pit 57 is formed on the floor surface 55a of the floor 55 along the back wall 53, and another drain pit 58 is formed along the slope of the floor surface 55a in the center. The immersion liquid taken out into the drain pits 57 and 58 is collected in the immersion liquid storage tank 61 through the pipe 59 and the pump 60. The immersion liquid is supplied from the immersion liquid storage tank 61 to the spray pipe 63 with the nozzle 62 attached below the ceiling wall 54 as necessary. In this structure, since the floor surface 55a of the floor 55 is formed as a sliding surface inclined downwardly from the front wall 52 toward the back wall 53, the charged fermentation biomass 56 is placed on the door 52b side. It can be prevented from moving, and there is no danger of an accident when opening the door 52b.
Special table 2004-511331 gazette

  However, in the garage-type biogas fermentation tank, the floor surface 55a of the floor 55 is inclined downwardly from the front wall 52 toward the back wall 53, so that fermentation is performed using a loading / unloading vehicle such as a loader. When carrying in the biomass 56 or carrying out the processing residue, it is difficult to operate the carry-in / out vehicle. Moreover, since the floor surface 55a of the floor 55 is inclined downwardly from the front wall 52 toward the back wall 53, the immersion liquid can be discharged only from the back wall 53, and the design freedom is achieved. In addition, when the garage biogas fermenter is installed, the installation location is greatly influenced by the surrounding environment.

  The present invention has been made in view of such circumstances, and it is easy to operate a loading / unloading vehicle at the time of loading of organic waste, etc., has a large degree of design freedom, and the installation location has little influence on the surrounding environment. The purpose of the present invention is to provide a batch-type biogas fermentation apparatus that does not receive it.

  In order to achieve the above-mentioned object, the batch type biogas fermentation apparatus of the present invention has a nozzle disposed in the upper space of the fermentation chamber that is kept in an airtight state, and is organically charged on the floor surface of the fermentation chamber. A biogas fermentation apparatus for spraying a methane solution containing methane bacteria on the waste from the nozzle and decomposing the organic waste with the methane bacteria to generate biogas, the floor surface of the fermentation chamber Is formed in a horizontal plane, a methane liquid recovery groove is formed in the floor surface, a methane liquid discharge groove communicating with the methane liquid recovery groove is formed in one side edge portion of the fermentation chamber floor surface, and the one side edge portion is formed. A methane solution recovery tank that collects and stores the methane solution that is formed along the methane solution recovery groove and is collected outside the fermentation chamber through the methane solution discharge groove is provided. To supply liquid to the nozzle Form was. Moreover, about the circulation path | route of the methane liquid, it was set as the structure which maintains an anaerobic state.

  That is, in the batch type biogas fermentation apparatus of the present invention, the nozzle is disposed in the upper space of the fermentation chamber held in an airtight state, and the organic waste put on the floor surface of the fermentation chamber is It is a biogas fermentation apparatus that sprays a methane solution containing methane bacteria from a nozzle and decomposes the organic waste with methane bacteria to generate biogas. The floor of the fermentation chamber is formed in a horizontal plane. A methane solution recovery groove is formed on the floor surface, and a methane solution discharge groove communicating with the methane solution recovery groove is formed along the one side edge portion on one side edge portion of the floor surface of the fermentation chamber. . A methane solution recovery tank is provided for recovering and storing the methane solution recovered in the methane solution recovery groove and discharged to the outside of the fermentation chamber through the methane solution discharge groove. The methane solution stored in the methane solution recovery tank is provided in the nozzle. Is used to circulate and reuse the methane solution. Thus, in the batch type biogas fermentation apparatus of the present invention, since the floor surface of the fermentation chamber is formed in a horizontal plane, when organic waste is carried in using a loading / unloading vehicle such as a loader or solid residue When carrying out as an organic fertilizer, operation of the said carrying in / out vehicle becomes easy. Moreover, a methane liquid discharge groove is provided along one side edge of the floor of the fermentation chamber along the one side edge, and a methane liquid recovery groove communicating with the methane liquid discharge groove is formed on the floor of the fermentation chamber. When the batch-type biogas fermentation apparatus of the present invention is installed, the place for taking out the methane solution from the fermentation chamber is determined according to the surrounding environment, and according to this determination, the methane solution discharge groove Can be formed at a desired one side edge of the floor surface of the fermentation chamber, thereby increasing the degree of freedom of design and making the installation location and the like unaffected by the surrounding environment.

  In addition, if the bottom surface of the methane liquid recovery groove is formed as an inclined surface inclined downward toward the methane liquid discharge groove, the methane liquid recovered in the methane liquid recovery groove can be easily recovered in the methane liquid discharge groove. Thus, the liquid circulation efficiency is improved. Moreover, there is no restriction | limiting in particular about the inclination angle of the said bottom face, Recovery of a methane liquid becomes still easier by enlarging an inclination angle, and liquid circulation efficiency improves further.

  The methane liquid discharge groove is provided with a discharge port for discharging the methane liquid flowing through the fermentation chamber to the outside of the fermentation chamber, and the bottom surface of the methane liquid discharge groove is formed in an inclined surface inclined downward toward the discharge port. Then, it becomes easy to discharge | emit the methane liquid which flows through the said methane liquid discharge groove | channel to a discharge port, and liquid circulation efficiency improves. Moreover, there is no restriction | limiting in particular about the inclination angle of the said bottom face, discharge | emission of a methane liquid becomes still easier by enlarging an inclination angle, and liquid circulation efficiency improves further. In addition, the said methane liquid discharge groove | channel is connected with the collection | recovery and circulation apparatus with the water seal structure, and is trying to maintain the airtightness of the inside of a fermentation chamber.

  Further, when the methane solution collecting groove is filled with a substance that can be a carrier for holding methane bacteria, the methane solution can be easily collected, and the amount of biogas generated is increased by improving the liquid circulation efficiency. As the holding carrier, a natural porous material such as rice husk or a nonwoven fabric is preferably used.

  Further, when the biogas generated in the fermentation chamber is taken out of the fermentation chamber and used as fuel for a boiler or a generator, the biogas can be effectively used as fuel for the boiler or generator. Moreover, in the said fermentation chamber, a solid residue can be manufactured and taken out as an organic fertilizer.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. However, it is not limited to this.

  1 and 2 show one embodiment of a batch type biogas fermentation apparatus of the present invention. In this embodiment, four fermentation chambers 1 are formed in the batch type biogas fermentation apparatus. In these drawings, reference numeral 2 denotes a steel front side wall, and the organic waste 10 is carried into the front side wall 2 with the upper portion 2a left, and a solid residue (not shown) is carried out. A loading / unloading port 2b is formed. Reference numeral 3 denotes a pair of left and right steel doors that open and close the loading / unloading port 2b in an airtight manner, and is rotatably attached to left and right side walls 4 and 5 and partition walls 9a to 9c, which will be described later. 4 and 5 are left and right side walls, 6 is a back side wall, 7 is a ceiling wall made of a heat insulating wall, 8 is a floor, and 9a to 9c are spaces surrounded by the walls 2, 4 to 7 and the floor 8 described above. Are the partition walls (the left partition wall 9a, the central partition wall 9b, and the right partition wall 9c), each made of concrete, and coated with antiseptic coating on the inside.

  Since each said wall 2, 4-7 and the floor | bed 8 are joined airtightly, and each said entrance / exit 2b can be closed airtightly by each door 3, each said fermentation chamber 1 is each door, respectively. When 3 is closed, the airtight state is maintained. In FIG. 1, reference numeral 20 denotes an air introduction pipe provided in each fermentation chamber 1, and the gas inside each fermentation chamber 1 is supplied after the fermentation is completed in order to ensure the safe operation of carrying in and carrying out the organic waste 10 and solid residue. It is for replacing with air. Reference numeral 26 denotes a ventilation pipe provided in each fermentation chamber 1, and a tip portion (one end portion) of the fermentation chamber 1 is inserted through a through hole formed in the upper end portion of the back side wall 6. Protrudes into the upper space. Then, the gas inside each fermentation chamber 1 is sent from the other end of the ventilation pipe 26 to the deodorizing device 33 by the ventilation blower 32 and released to the atmosphere.

  The floor 8 of each fermentation chamber 1 has a floor surface 8a formed on a horizontal surface (horizontal flat surface) (see FIG. 1), and the floor surface 8a has a predetermined distance behind the front end surface. Three methane liquid recovery grooves 11 extending in a straight line from the approached position to the back end face are respectively cut out in parallel (with the left and right side walls 4 and 5 and the partition walls 9a to 9c) (see FIG. 2). ). Each of these methane liquid recovery grooves 11 is formed in an inclined surface whose bottom surface 11a is inclined downwardly toward the back end surface (that is, a methane liquid discharge groove 13 described later) (see FIG. 3). The inside of each methane liquid recovery groove 11 is filled with rice husks (not shown) so that the methane liquid can be easily recovered.

  In addition, on the floor surface 8 a of the floor 8 of each fermentation chamber 1, a single methane liquid discharge groove 13 extending along the back side wall 6 is formed on the back end surface. These four methane liquid discharge grooves 13 are formed on inclined surfaces that are inclined downward toward the left and right partition walls 9a, 9c, and the methane liquid discharge grooves 13 (on the partition walls 9a, 9c side) are formed. ) A discharge port (not shown) is formed at the end. More specifically, the left end methane solution discharge groove 13 formed in the left end fermentation chamber 1 extends from the end of the left end methane solution recovery groove 11 to the left partition wall 9a and is formed in the fermentation chamber 1 on the left side of the center. The center left methane solution discharge groove 13 extends from the end of the right end methane solution recovery groove 11 to the left partition wall 9a, and the bottom surfaces of both methane solution discharge grooves 13 are the left partition wall 9a (both methane solution discharge grooves). (13 outlets) are formed on an inclined surface inclined downwardly. A central right methane solution discharge groove 13 formed in the right fermentation chamber 1 extends from the end of the left end methane solution recovery groove 11 to the right partition wall 9c and is formed in the right fermentation chamber 1. The right end methane liquid discharge groove 13 extends from the end of the right end methane liquid recovery groove 11 to the right partition wall 9c, and the bottom surfaces of both the methane liquid discharge grooves 13 are connected to the right partition wall 9c (the discharge of both methane liquid discharge grooves 13). It is formed on an inclined surface that inclines downward toward the exit.

  Reference numerals 15 and 16 denote manholes disposed on the rear side of the back side wall 6 (parts corresponding to the left and right partition walls 9a and 9c). The left manhole 15 is connected to the left end methane liquid via the first communication pipe 17a. It communicates with the discharge port of the discharge groove 13 and communicates with the discharge port of the central left methane liquid discharge groove 13 via the second communication pipe 17b. The right manhole 16 communicates with the discharge port of the central right methane solution discharge groove 13 through the third communication pipe 17c, and communicates with the discharge port of the right end methane solution discharge groove 13 through the fourth communication pipe 17d. Yes. Each said methane liquid discharge groove | channel 13 is connected with each communication pipe 17a-17d by the water seal structure, and the airtight inside the fermentation chamber 1 is maintained. Further, the right manhole 16 is formed lower than the left manhole 15, and both the manholes 15 and 16 are connected via a first connecting pipe 18 inclined downward toward the right side. A methane solution storage tank 21 formed lower than this is disposed on the right side of the manhole 16 and is connected via a second connection pipe 19 inclined downward toward the right side. .

  A plurality of spray nozzles 22 for spraying the methane liquid are attached to the first methane liquid supply pipe 23 disposed in the upper space of each fermentation chamber 1. Each of the first methane liquid supply pipes 23 is connected to the methane liquid storage tank 21 via a second methane liquid supply pipe 24 having a pump 25, and the methane stored in the methane liquid storage tank 21. The liquid is supplied to the nozzles 22 through the supply pipes 23 and 24 by the pump 25.

  Reference numeral 27 denotes a gas pipe, and the tip of the gas pipe passes through the ceiling wall 7 of each fermentation chamber 1 and opens into the fermentation chamber 1. The biogas generated in each fermentation chamber 1 communicates with the gas recovery holder 29 via the desulfurization device 28.

  A gas supply blower 34 supplies the biogas in the gas recovery holder 29 to the boiler 35 or the power generator 36. The boiler 35 burns part or all of the supplied biogas to produce hot water. Hot water is supplied to the floor 8 and the temperature control pipe 38 embedded in the methane solution storage tank 21 via the feed pipe 37 and then returned to the boiler 35 via the return pipe 39. The temperature of the waste 10 and the methane liquid is kept uniform. Further, in the power generation device 36, a part or all of the supplied biogas is combusted to extract power and heat, and hot water is produced using this heat. The temperature is kept uniform, and the electricity taken out from the power generator 36 is supplied to the electrical equipment of the batch type biogas fermentation apparatus of the present invention.

  Using the above-described batch type biogas fermentation apparatus, the organic waste 10 can be decomposed by methane fermentation to generate biogas as described below, and the fixed residue can be produced as an organic fertilizer. That is, first, the organic waste 10 is pre-processed (moisture-adjusted), put into each fermentation chamber 1 using a loader or the like, then the door 3 of each fermentation chamber 1 is closed, and each fermentation chamber 1 is closed. To be airtight. Next, the methane solution (containing methane bacteria) in the methane solution storage tank 21 is supplied to each spray nozzle 22 by a pump 25, and is put on the floor surface 8 a of each fermentation chamber 1 from each spray nozzle 22. Spread evenly on the upper surface of the organic waste 10. Thereby, the organic waste 10 is decomposed | disassembled by methane bacteria, and biogas is generated. The methane solution passes through each methane solution recovery groove 11 and the methane solution discharge groove 13 on the floor surface 8a and is recovered in the methane solution storage tank 21, and then supplied to each spray nozzle 22 by the pump 25 as described above. , Sprayed from each spray nozzle 22. The circulation of the methane solution maintains the activity of methane bacteria. On the other hand, the generated biogas is collected in the gas pipe 27 and is automatically controlled and recovered in the gas recovery holder 29 according to the components of the biogas. Fixed residue is used as organic fertilizer.

  As described above, in this embodiment, since the floor surface 8a of the floor 8 of each fermentation chamber 1 is formed in a horizontal plane, the organic waste 10 is carried in using a loading / unloading vehicle such as a loader. And when carrying out solid residue as organic fertilizer, operation of the said carrying in / out vehicle becomes easy. Moreover, a methane liquid discharge groove 13 is provided along one side edge of the floor surface 8a, and each methane liquid recovery groove 11 communicating with the methane liquid discharge groove 13 is provided in the fermentation chamber 1. Since it forms in the floor surface 8a, when installing the batch type biogas fermentation apparatus of this invention, the place which takes out a methane liquid from each fermentation chamber 1 according to the surrounding environment is determined, and according to this determination The methane solution discharge groove 13 can be formed at a desired one side edge of the floor surface 8a of each fermentation chamber 1, thereby increasing design flexibility and surrounding the installation location etc. Unaffected by the environment.

  FIG. 4 shows a modification of the methane solution recovery groove 11 and the methane solution discharge groove 13 formed on the floor surface 8 a of the floor 8 of each fermentation chamber 1. In this example, the methane liquid recovery groove 11 has a central groove 41 that extends in a straight line from a position closer to the back side by a predetermined distance from the front end surface to the back end surface at the center in the left-right direction of the floor surface 8a. The ten branch grooves 42 (the five branch grooves 42 on the left side and the five branch grooves 42 on the right side) extending forward from the central groove 41 in the left-right direction at a predetermined inclination angle.

  The methane liquid discharge groove 13 is formed across the entire width in the left-right direction on the rear end surface of the floor surface 8a of the floor 8 of each fermentation chamber 1, and a discharge port (not shown) is formed in the center in the left-right direction. ing. The bottom surface 13a of the methane liquid discharge groove 13 is formed as an inclined surface that is inclined downwardly from the left and right ends of the methane liquid discharge groove 13 toward the discharge port. The central groove 41 of the methane liquid recovery groove 11 is formed in an inclined surface whose bottom surface 41a is inclined downwardly toward the back end surface (that is, the discharge port of the methane liquid discharge groove 13), Each branch groove 42 is formed in an inclined surface whose bottom surface 42 a is inclined downward toward the central groove 41. Moreover, in this example, the manhole 43 is provided corresponding to each said fermentation chamber 1, and is connected to the discharge port of the methane liquid discharge groove | channel 13 of each said fermentation chamber 1 via the communication pipe 43a. Other parts are the same as those in the above embodiment, and the same reference numerals are given to the same parts. Even when the methane liquid recovery groove 11 and the methane liquid discharge groove 13 of this example are used, the same operations and effects as those of the above embodiment are obtained.

  In the above embodiment, the bottom surfaces 11a, 13a, 41a, and 42a of each methane solution recovery groove 11 and each methane solution discharge groove 13 are formed as inclined surfaces. However, the present invention is not limited to this. At least one of the liquid recovery groove 11 and each methane liquid discharge groove 13 may be formed on a horizontal plane.

  In the above embodiment, the power generation device 36 may be a power generation device for reforming and purifying a part or all of the biogas supplied from the gas recovery holder 29 and reacting it. It may be a refining device that uses some or all of the biogas produced to concentrate the combustible components, or it uses some or all of the biogas that is supplied to concentrate, fill, and heat the combustible components. It may be a refining / filling / caloric adjustment device to be adjusted, or may be provided with a transport mechanism for transporting it in a pipeline as it is or after being refined in order to use part or all of the supplied biogas. In order to use part or all of the supplied biogas, it is equipped with a transport mechanism that transports it as it is or purified or transported by pipeline after adjusting the amount of heat. It may be.

  Next, embodiments of the present invention will be described in detail.

  FIG. 5 shows a batch type biogas fermentation apparatus used in the embodiment of the present invention. This fermenter treats 13 tons of efficient organic waste (pig manure, chicken manure, pruned branch, raw garbage) by anaerobic fermentation for 28 days, and for a short time (60 in general aerobic fermentation treatment). The goal is to process at least fermentation days. The generated biogas (methane concentration 45% by volume or more) is burned by the biogas boiler 69b and the generator 70, and the generated heat maintains the temperature of the first to fourth fermentation tanks 60a to 60d and the methane liquid storage tank 62. To use.

  First, as a preliminary preparation for starting methane fermentation, fermentation for curing methane bacteria was performed. As input materials, about 2 tons of pig feces, pruned branches, and the like were added to the fourth fermenter 60d, and the raw materials were heated to 38 ° C. As a heating method, the LPG boiler 69a was operated, and hot water was supplied to floor heating. After the raw material was charged, the fourth fermenter hermetic door 61d was closed to maintain the anaerobic state. Initially, the raw material used was aerobic fermentation using oxygen remaining in the upper air layer in the fourth fermenter 60d, but the oxygen concentration in the fourth fermenter 60d was 0% in about 60 hours. became. This state was maintained for 2 months, and methane bacteria were cured.

  In addition, along with the above curing, methane bacteria curing in the methane solution storage tank 62 was performed. As input materials, about 3 tons of chicken manure, water, activated sludge, bread crumbs, etc. are put into the methane solution storage tank 62, and the methane solution is heated to 38 ° C by floor heating attached to the bottom of the methane solution storage tank 62. The temperature was maintained. This state was maintained for 2 months to promote anaerobic fermentation. The methane concentration in the methane liquid storage tank 62 exceeded 40% by volume in one month.

  About 11 tons of pig manure / chicken manure mixture is further mixed with the inoculum (the raw material introduced into the fourth fermenter 60d) after curing, and the mixture is introduced into the third fermenter 60c. Went. A decrease in oxygen concentration and an increase in methane concentration in the upper air layer in the third fermenter 60c were confirmed.

  Subsequently, the methane solution cured in the methane solution storage tank 62 was sprayed by the methane solution supply pump 63 onto the raw material charged into the third fermenter 60 c. There is no outflow of methane liquid to the outside (particularly, the third fermenter airtight door 61c), and the floor of the inner floor of the third fermenter 60c (not shown in the above embodiment, which has the same structure as the floor 8) is used. There was no effect from leveling.

  The methane solution is a methane solution recovery circuit (not shown) attached to the third fermenter 60c. In the above embodiment, the methane solution recovery groove 11, the methane solution discharge groove 13, the manholes 15 and 16, the connection pipe 18, It was recovered in the methane liquid storage tank 62 by the same structure as in FIG. Since the raw material moisture was as low as 62% by volume, it was absorbed to some extent by the raw material, but about 85% by volume of methane liquid was confirmed to be recovered. The recovery rate of this methane liquid became higher as the days of fermentation progressed. The reduced amount of the methane solution maintained the capacity of the methane solution storage tank 62 by supplying tap water.

  The above state was maintained for about 2 months to promote anaerobic fermentation. As for the state of fermentation, the methane concentration increased steadily after the raw material was charged, and exceeded the methane concentration of 60 vol% assumed on the 25th. The amount of biogas generated was 1300 liters per day. Thereby, it was confirmed that the favorable anaerobic fermentation is progressing in the 3rd fermenter 60c. Furthermore, the raw material was thrown into the 1st fermenter 60a and the 2nd fermenter 60b, and the same result was obtained. From this result, it can be seen that if the number of methane bacteria in the first to fourth fermenters 60a to 60d increases, an increase in methane concentration in a short time is expected.

  The biogas generated from the first to fourth fermenters 60a to 60d contained about 600 to 2000 ppm of hydrogen sulfide. The biogas was stored in a gas pack (gas recovery holder) 67 after removing hydrogen sulfide to 0% by a desulfurization tank 66. The stored biogas is burned by the biogas boiler 69b and the generator 70 via the gas supply blower 68 as the temperature of the first to fourth fermenters 60a to 60d and the methane solution storage tank 62 decreases, and hot water is supplied. Thus, the fermentation temperature was maintained. The heat generated from the generator 70 was exchanged by a hot water circuit (not shown) for floor heating and a heat exchanger 71, and excess heat in the hot water storage tank 72 was stored as hot water. The generated power was used as a lamp power source.

  About fermenter 60a-60d which anaerobic fermentation was complete | finished, the gas in the inside was attracted | sucked with the ventilation blower 64 from the pipe for ventilation (not shown), and it ventilated. The exhausted gas was released into the atmosphere through the deodorization tank 65. In order to prevent oxygen deficiency and hydrogen sulfide poisoning, before opening the first to fourth fermenter airtight doors 61a to 61d, until the oxygen concentration in the first to fourth fermenters 60a to 60d is 20% by volume or more, The system was inaccessible.

  The residue after fermentation was carried out of the first to fourth fermenters 60a to 60d by a front loader (not shown). Since the floor surfaces of the inner floors of the first to fourth fermenters 60a to 60d are horizontal with the ground surface, the residues can be carried out and the raw materials can be charged efficiently.

  At the time of carrying out the residue, no foul odors were generated from general pig dung and chicken dung treatment facilities. From this, it is considered that the organic acids that are the source of the odor were sufficiently decomposed, and sufficient organic waste was treated in the fermentation days of 28 days. From the above results, it is possible to confirm the improvement in workability of raw material input and residue carry-out by leveling the inner floors of the first to fourth fermenters 60a to 60d, and further improving the efficiency of anaerobic fermentation by smooth circulation of methane liquid Was confirmed.

It is a block diagram which shows one Embodiment of the batch type biogas fermentation apparatus of this invention. It is sectional drawing of the principal part of the said batch type biogas fermentation apparatus. It is a perspective view of the principal part of a methane liquid recovery groove and a methane liquid discharge groove. It is explanatory drawing which shows the modification of the said methane liquid collection | recovery groove | channel and a methane liquid discharge groove | channel. It is explanatory drawing which shows an Example. It is explanatory drawing which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fermentation room 8a Fermentation room floor surface 10 Organic waste 11 Methane liquid recovery groove 13 Methane liquid discharge groove 22 Spray nozzle

Claims (5)

  A nozzle is arranged in the upper space of the fermentation chamber kept in an airtight state, and methane liquid containing methane fermentation bacteria is sprayed from the nozzle onto the organic waste put on the floor surface of the fermentation chamber. A biogas fermentation apparatus that decomposes the organic waste with methane fermentation bacteria to generate biogas, wherein the floor of the fermentation chamber is formed in a horizontal plane, and a methane liquid recovery groove is formed in the floor. A methane liquid discharge groove communicating with the methane liquid recovery groove is formed along one side edge of the fermentation chamber floor along the one side edge, and the methane liquid discharge is recovered in the methane liquid recovery groove. A batch comprising a methane solution recovery tank for recovering and storing the methane solution discharged outside the fermentation chamber through the groove, and supplying the methane solution stored in the methane solution recovery tank to the nozzle. Type biogas fermentation equipment.   The batch-type biogas fermentation apparatus according to claim 1, wherein the bottom surface of the methane solution recovery groove is formed on an inclined surface that is inclined downward toward the methane solution discharge groove.   The methane solution discharge groove is provided with a discharge port for discharging the methane solution flowing therethrough to the outside of the fermentation chamber, and the bottom surface of the methane solution discharge groove is formed as an inclined surface that is inclined downward toward the discharge port. Item 3. A batch-type biogas fermentation apparatus according to item 2.   The batch-type biogas fermentation apparatus as described in any one of Claims 1-3 which filled the substance which can become a holding | maintenance support | carrier of methane fermentation bacteria in the said methane liquid collection | recovery groove | channel. The batch type biogas fermentation apparatus according to any one of claims 1 to 4, wherein the biogas generated in the fermentation chamber is taken out of the fermentation chamber and used as fuel for a boiler or a generator.

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