JP2011121042A - Organic waste treatment apparatus and fermentation treatment method for organic waste - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic waste treatment apparatus which enables an aerobic fermentation of organic waste after an anaerobic fermentation as it is continuously. <P>SOLUTION: The apparatus comprises a fermenter 40 capable of keeping an air-tight state, a pumping-up pump 18 pumping a treatment liquid S containing methanogenic bacteria, an injection nozzle 19 injecting the treatment liquid S, a floor board 15 having a plurality of pores 16, and an air feeding means 41 connected with the fermenter 40. The fermenter 40 is a component type having a rotary shaft 46 standing enabling an axial rotation and a plurality of stirring blades 47 provided around the rotary shaft 46. The treatment liquid S is pooled in a space below the floor board 15. The pumping-up pump 18 stops after the anaerobic fermentation in the air-tight state while driving the pumping-up pump 18, and subsequently fermentation residues after the anaerobic fermentation while driving the air feeding means 41 can be subjected to the aerobic fermentation treatment in the fermenter 40 as they are. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a treatment apparatus for obtaining biogas from organic waste and a method for fermentation treatment of organic waste using the same.

Conventionally, environmental problems associated with mass consumption of fossil fuels such as oil have become prominent. Specifically, there are problems of global warming due to CO ₂ generated by the combustion of fossil fuels and depletion of fossil fuels which are limited resources. Therefore, in recent years, an alternative fuel replacing fossil fuel has attracted attention, and one of them is biogas obtained from organic waste (biomass). When fossil fuel is burned, CO ₂ is unilaterally generated, increasing the amount of CO _{2 on the} entire earth. On the other hand, with biogas fuel derived from organic waste, the CO ₂ once taken in by organic waste is only returned to the atmosphere, and the amount of CO _{2 on the} entire earth does not increase (carbon neutral). Is low. Moreover, the organic waste derived from animals and plants is an infinite resource as long as the animals and plants are alive, and there is no problem of depletion.

  Therefore, as a processing apparatus for obtaining biogas from organic waste, for example, there is Patent Document 1 below. In Patent Document 1, methane gas is obtained by anaerobic fermentation of organic waste using a batch-type garage fermenter. This processing apparatus has a structure that can efficiently process organic waste by inclining the floor surface of the fermenter downward from the organic waste loading / unloading port toward the back wall. Outside the fermenter, a processing liquid tank that stores a processing liquid containing methanogenic bacteria (methane bacteria) that anaerobically ferment organic wastes is provided next to the fermenter. The processing liquid in the processing liquid tank is pumped up to the upper part of the fermenter by a pumping pump, and sprayed from above the organic waste through the nozzle. The sprayed processing liquid permeates the organic waste, reaches a drainage passage (drainage pit) extending vertically and horizontally provided on the bottom wall, and is released again to the processing liquid tank by a release pump.

  On the other hand, biogas generated from organic waste in the fermenter is sucked and exhausted from the exhaust port by a suction blower. This biogas is stored in a pressure tank, and part of it is sent to a biogas generator such as a co-generation generator. A co-generation generator generates heat as well as power generation. Therefore, the heat generated by the co-generation generator is effectively used for heating (warming) the treatment liquid and the fermenter via the heat exchanger. Gases that cannot be used as biogas fuel, such as the decay process of organic waste and the mixed gas generated when ventilating the fermenter after fermentation, are released into the atmosphere after being purified by a biofilter. . A ventilating window that can be opened and closed is provided on the door of the processing chamber.

JP-T-2004-511331

  Patent Document 1 uses biogas obtained from organic waste as fuel and is environmentally friendly. And since it is fermented by a dry type, pretreatment like wet fermentation is unnecessary. In addition, since the heat generated during power generation using the obtained biogas is effectively used for heating the processing liquid and the processing chamber, it is efficient. However, the processing liquid tank for storing the processing liquid containing methane bacteria is adjacent to the outside of the fermenter, and the processing liquid injected into the fermenter is pumped from a drainage passage extending vertically and horizontally provided in the bottom wall. Is released to the processing liquid tank. In this case, the structure is complicated, and it takes time and effort to provide a drainage passage in the bottom wall, which increases the manufacturing cost. In addition, a release pump for releasing to the processing liquid tank is necessary, and accordingly, the apparatus is inevitably increased in size and energy cost. Moreover, in order to accurately release the processing liquid by the release pump, the drainage passage must be inclined toward the release pump, and the manufacturing is complicated. Moreover, if the processing liquid tank is adjacent to the outside of the fermenter, the installation area of the processing apparatus becomes large. There are problems such as.

  Moreover, in the processing apparatus of patent document 1, although biogas can be obtained from organic waste, the process of further composting the fermentation residue after anaerobic fermentation cannot be performed. In this case, post-treatment such as composting the fermentation residue after anaerobic fermentation is only efficient after transferring to a dedicated processing device prepared separately.

  Therefore, the present invention has been made to solve such a problem, and provides an organic waste treatment apparatus capable of efficiently circulating a treatment liquid while suppressing costs with a relatively simple configuration. With the goal. Furthermore, it aims at providing the organic waste processing apparatus which can post-process the organic waste after anaerobic fermentation continuously.

  The present invention includes a fermenter capable of maintaining an airtight state, a pumping pump that pumps a treatment liquid containing methanogenic bacteria that anaerobically ferment organic waste to generate methane, and an upper pump. An organic waste treatment apparatus for obtaining biogas by anaerobically fermenting organic waste in the fermentor, having an injection nozzle for injecting the pumped processing liquid from the upper part of the fermenter, A floor board having a plurality of pores is disposed at an upper position from the bottom wall of the fermenter, the organic waste is deposited on the floor board and fermented, and the treatment liquid is stored in a lower space of the floor board. Yes. In this case, the floor board may be inclined, but the floor board may be disposed horizontally.

  The fermenter is a component-type (container-type) fermenter that includes a rotary shaft that is erected so as to be axially rotatable inside the fermenter and a stirring blade that is provided around the rotary shaft. An air supply means is connected to the fermenter. Thus, after the organic waste is anaerobically fermented in an airtight state while driving the pumping pump, the pumping pump is stopped, and then the fermentation residue after the anaerobic fermentation is left as it is while driving the air feeding means. Aerobic fermentation can be performed in the fermenter.

  The rotating shaft has a hollow cylindrical shape, the air feeding means is connected to a lower end of the rotating shaft, and the stirring blades are provided in a plurality of upper and lower stages around the rotating shaft. Among the blades, at least the lowermost stirring blade is made hollow, and a plurality of ventilation holes are formed so as to penetrate inside and outside, and when the fermentation residue is subjected to aerobic fermentation, air is fed from the air feeding means. It is preferable that the air thus supplied is sent from the lower part of the fermenter through the vent hole of the stirring blade.

  It is preferable that the stirring blade has a mountain shape having a swash plate on the front side in the rotation direction, the vent hole is provided on the rear side in the rotation direction, and a hook piece is provided above the vent hole.

  In addition, a fermenter capable of maintaining an airtight state, a pump that pumps a treatment liquid containing methanogenic bacteria that anaerobically ferment organic waste to generate methane, and pumped by the pump An injection nozzle for injecting a treatment liquid from the upper part of the fermenter, a floor plate having a plurality of pores arranged at an upper position from the bottom wall of the fermenter, and an air supply means connected to the fermenter The fermenter is a component-type fermenter that includes a rotating shaft that is erected so as to be axially rotatable inside the fermenter, and a stirring blade that is provided around the rotating shaft. A method for fermenting organic waste, wherein the organic waste is fermented by an organic waste processing apparatus stored in a lower space of a floor board, and the organic waste is airtight while driving the pump. Anaerobically fermented An organic waste fermentation treatment method is also proposed in which the pumping pump is stopped, and then the fermentation residue after the anaerobic fermentation is aerobically fermented as it is in the fermenter while driving the air supply means. .

  According to the present invention, since the processing liquid for anaerobically fermenting organic waste is stored in the underfloor space in the fermenter, it is not necessary to separately provide a processing liquid tank, and the installation area of the apparatus can be reduced. Further, since the sprayed processing liquid can be dropped and collected into the lower layer space through the floor plate, it is not necessary to provide a drainage passage for discharging the processing liquid to the outside of the fermenter, and a simple configuration can be achieved. In addition, since a release pump for releasing the processing liquid from the drainage passage to the processing liquid tank is not required, it is possible to reduce the energy cost as well as downsizing and simplifying the apparatus.

  If it becomes such a structure, it is not necessary to incline a floor board. Therefore, the manufacture and assembly of the device are facilitated. Even if the floorboards are arranged horizontally, the treatment liquid can be efficiently recovered.

  If a component-type fermenter having a rotating shaft and stirring blades therein is used, the organic waste can be efficiently fermented while stirring. In addition, if an air supply means is provided in the fermenter, the fermentation residue after anaerobic fermentation of organic waste in an airtight state can be aerobically fermented as it is in the same fermentor, so that biogas recovery processing And the fermentation residue composting process can be performed continuously. Therefore, compost can be obtained simultaneously with fuel for electric power and heat from one processing apparatus, which is economical.

  When the fermentation residue is aerobically fermented, if the air supplied from the air supply means is supplied from the bottom of the fermenter through the vent of the stirring blade, it is aerobic with a simple structure and efficient ventilation. It can be fermented and the processing capacity is improved.

It is a schematic cross section of the garage type processing apparatus concerning a reference example. In the component-type processing apparatus which concerns on an Example, it is a schematic cross section which shows an anaerobic fermentation state. In the component-type processing apparatus which concerns on an Example, it is a schematic cross section of the fermenter which shows an aerobic fermentation state. It is sectional drawing of a stirring blade.

  Hereinafter, the present invention will be described with reference to the drawings. However, the present invention is not limited thereto, and various modifications can be made without departing from the gist of the present invention. The organic waste treatment apparatus of the present invention ferments the organic waste (biomass) by anaerobic fermentation to obtain biogas, and then ferments the fermentation residue after the anaerobic fermentation with an aerobic microorganism in an aerobic environment. Composted. It is a processing device. The organic waste is not particularly limited as long as it is a waste derived from animals and plants, and examples thereof include livestock excrement and food residues. Examples of livestock droppings include poultry droppings such as chicken droppings, and livestock droppings such as pig droppings and cow droppings. Examples of food residues include food waste and food production by-products generated from the food manufacturing industry, restaurant industry, food distribution industry, and the like. Examples of food waste include fish scraps, meat scraps, vegetable scraps and the like left over from the food service industry, as well as fishery products, meat, and vegetables. Examples of food production by-products include brewing by-products such as sake lees, shochu, beer lees, miso, and fruit juice residue, as well as remaining okara from squeezed soy milk during tofu production. Other examples include building waste and agricultural waste such as rice straw and rice husks. Only one type of these organic wastes may be processed alone, or a plurality of types may be mixed. In addition, food waste such as food waste and food residues is preferable in that biogas is generated in a larger amount than livestock dung.

  Biogas is a gas produced by anaerobic fermentation of organic waste. The main component of biogas is methane, which can be used as an alternative fuel for fossil fuels for power generation, cogeneration (both cogeneration), boilers, vehicle engines, and cooking. For the fermentation of organic waste, a treatment solution containing methanogenic bacteria (methane bacteria) is used. The methanogenic bacterium is not particularly limited as long as it is a microorganism having methane fermentation ability. For example, bacteria belonging to the genus Methanobacterium, bacteria belonging to the genus Methanobrevibacter, bacteria belonging to the genus Methanococcus, bacteria belonging to the genus Methanomicrobium, belonging to the genus Methanogenium Examples include bacteria, bacteria belonging to the genus Methanospirillum, bacteria belonging to the genus Methanosarcina (acetic acid-assimilating methanogenic archaea), bacteria belonging to the genus Methanosaeta (acetic acid-assimilating methanogenic archaea), and the like. These methanogenic bacteria may be used alone or in combination of two or more. Based on this premise, specific examples of the organic waste treatment apparatus of the present invention will be described.

(Reference example)
First, before describing the embodiments of the present invention, reference examples related to the present invention will be described. FIG. 1 shows an organic waste treatment apparatus according to a reference example. In addition, in FIG. 1, the fermenter 10 is shown by the cross section, showing typically the whole structure of an organic waste processing apparatus. The processing apparatus of the reference example has a garage type fermenter 10 as shown in FIG. The fermenter 10 is made of concrete, and an open / close door 11 for carrying in and out the organic waste W, an exhaust port 12 for exhausting the gas in the fermenter 10, and concentration detection for detecting the methane concentration in the fermenter 10. A density sensor 25 is provided as a means. The open / close door 11 is provided with a ventilation window 13 capable of switching the fermenter 10 between an airtight state and a vented state, and a lock mechanism (not shown) that prevents the open / close door 11 from being opened and closed. The open / close door 11 is provided at a position above the bottom wall 10b of the fermenter 10 by a predetermined amount. The lock timing of the lock mechanism of the open / close door 11 and the open / close timing of the ventilation window 13 are controlled by a control device (not shown) based on a detection signal from the concentration sensor 25. The exhaust port 12 is provided in the upper part of the back wall 10 d facing the open / close door 11.

  In the fermenter 10, a floor plate 15 is disposed at a position above the bottom wall 10b by a predetermined amount. What is necessary is just to arrange | position the floor board 15 by mounting or engaging with the stopper (not shown) provided in the inner surface of the fermenter 10, or bolting directly to the fermenter 10. FIG. The floor board 15 is at a height position below the ground G. It is preferable to be substantially flush with the ground G. The floor plate 15 has a plurality of pores 16 over the entire surface. The diameter of the pores 16 is not allowed to pass through the organic waste W, but may be set to a size that allows liquid to pass through. As such a floor board 15, a punching metal, a metal mesh, etc. can be used. In addition, the processing liquid S is stored in a space below the floor board 15 (hereinafter referred to as an underfloor space).

  A pumping pipe 17 is provided from the underfloor space to the upper part in the fermenter 10. A pumping pump 18 is provided in the middle of the pumping pipe 17, and the processing liquid S in the underfloor space is pumped up to the upper part of the fermenter 10 by the pumping pump 18. A plurality of injection nozzles 19 for injecting the pumped processing liquid S in a mist form are provided at the tip of the pumping pipe 17.

  A plurality of heat pipes 22 filled with a liquid heat transfer medium (typically water) are embedded in the bottom wall 10b of the fermenter 10 throughout. In addition, it is also preferable to embed the heat pipe 22 over the entire wall surface of the fermenter 10, such as the bottom wall 10b, the back wall 10d, the top wall 10r, and the side walls not shown. According to this, not only the space under the floor but also the space above the floor can be heated. Moreover, it is also possible to use a cover having elasticity that can flexibly cope with the volume change inside the fermenter 10 instead of the concrete top wall 10r. This is advantageous in that the fermenter 10 itself functions as a buffer storage tank for the biogas generated. A predetermined amount of organic waste W is carried into the fermenter 10 in a batch manner by a transport vehicle such as an excavator loader.

  In addition, the organic waste treatment apparatus of this reference example includes a suction blower 30 that actively sucks and exhausts biogas generated in the fermenter 10 from the exhaust port 12, and a gas pack 31 that compresses and stores the obtained biogas. And a gas engine generator 32 that generates power using biogas, and a bio-purifier that purifies unnecessary gas such as mixed gas generated when ventilating the fermenter 10 after the decay process or fermentation of the organic waste W A filter 33 is provided. The gas pack 31 is placed on the top wall 10r (attic) of the fermenter 10, and the gas engine generator 32 and the biofilter 33 are provided outside the fermenter 10. By providing the gas pack 31 in the attic, the overall installation area of the organic waste treatment apparatus can be reduced. An exhaust pipe 34 is connected in a branched manner from the exhaust port 12 to the gas pack 31 and the biofilter 33, and the suction blower 30 is provided on the exhaust pipe 34. In addition, a three-way valve 35 is provided at the branch point of the exhaust pipe 34 to switch the biogas between the gas pack 31 and the biofilter 33 and send the gas.

  The gas engine generator 32 is connected to a gas pack 31 and generates power using biogas in the gas pack 31. In this reference example, a co-generator capable of supplying heat together with electric power is used as the gas engine generator 32. The co-generation generator 32 is a water-cooled generator, and heat (heated cooling water) generated by the co-generation generator 32 is passed through a heat exchanger 36 provided on the pumping pipe 17. It is transmitted to the processing liquid S. As a result, the treatment liquid S is heated and then sprayed from each spray nozzle 19. Further, the heat (heated cooling water) generated by the co-generation generator 32 is transmitted also into the heat pipe 22 and used for heating the fermenter 10. Reference numerals 26 and 27 are pumps that pump the cooling water of the co-generation generator 32. The pumping pump 18 and the pumps 26 and 27 also have a fluid backflow prevention (check valve) function.

  The biofilter 33 is filled with a purifying material M such as wood chips, bark and compost on a filter 37 having air permeability. Since unnecessary gas is vented from the lower layer to the upper layer of the biofilter 33, the gas purified and deodorized by the purification material M is released from the upper part of the biofilter 33 into the atmosphere. In addition, it is also preferable that a plurality of upper and lower stages of filters 37 are provided in the biofilter 33 so that each layer divided by each filter 37 is filled with a different purification material M.

  Next, the operation of the organic matter processing apparatus will be described. First, the opening / closing door 11 is opened, a predetermined amount of organic waste W is carried in by a transport vehicle such as an excavator loader, and deposited on the floor plate 15. At this time, if the floor board 15 and the ground G are substantially flush with each other, the conveyance vehicle can smoothly enter the fermenter 10. The processing apparatus of this reference example is a dry fermentation apparatus, and basically the pretreatment of the organic waste W is unnecessary. If the organic waste has a large size such as building waste, it is preferable to cut or pulverize it to some extent as appropriate. This is because the smaller the size, the easier the fermentation and the shorter the processing time.

  When a predetermined amount of organic waste W can be carried into the fermenter 10, the open / close door 11 is closed and the processing apparatus is operated. Then, the door 11 is locked by the control device, and the ventilation window 13 is closed, so that the inside of the fermenter 10 is airtight. Then, the processing liquid S stored in the underfloor space is pumped up by the pumping pump 18, and the processing liquid S is injected from above the organic waste W through the injection nozzle 19 and penetrates into the organic waste W. Then, the organic waste W is anaerobically fermented (oxygen-free fermentation) by the action of the methanogenic bacteria in the treatment liquid S, and biogas is generated. The treatment liquid S that has penetrated into the organic waste W is dropped and collected into the space under the floor through the pores 16 of the floor board 15. The methane concentration in the biogas is about 55 to 70%, although it varies slightly depending on the type of organic waste W and methane-producing bacteria. The other gas is mainly carbon dioxide. In addition, in this reference example, the process liquid S and the fermenter 10 are heated as mentioned later, and medium temperature fermentation is carried out at about 35-40 degreeC.

  Biogas generated in the fermenter 10 is actively sucked and exhausted from the exhaust port 12 by the suction blower 30 and stored in the gas pack 31. At this time, biogas is not sent to the biofilter 33 by the three-way valve 35. Part of the biogas stored in the gas pack 31 is also used as fuel for the co-generation generator 32. The electric power thus obtained can be used as driving energy for various devices and devices, or can be used as a source of income from electric power sales. Further, the co-generation generator 32 supplies heat together with electric power. This heat is transmitted to the processing liquid S through the heat exchanger 36, and the processing liquid S is heated and held at an appropriate temperature. Moreover, the fermenter 10 is also heated by heat being transmitted also in the heat pipe 22. Thereby, the anaerobic fermentation of the organic waste W is promoted. The heat generated from the co-generation generator 32 is used for heating other recreational facilities such as zoos and amusement parks, greenhouses and public facilities, heated pools, use of heat in the factory, heating of compost fermentation, snow melting It can also be used for sludge drying.

  When the anaerobic fermentation of the organic waste W is almost completed, the pumping pump 18 is stopped by the control device, the ventilation window 13 is opened, and the three-way valve 35 is switched to the biofilter 33 side. Such a control timing can be set after the time sufficient for anaerobic fermentation of the organic waste W or when the concentration sensor 25 detects that the methane concentration in the fermenter 10 has decreased. Moreover, you may carry out manually. Thereby, the inside of the fermenter 10 is ventilated by introducing fresh air (outside air) into the fermenter 10 from the ventilation window 13. Unnecessary gas in the fermenter 10 is sent to the biofilter 33 through the three-way valve 35, purified and deodorized, and then released into the atmosphere. Thereby, air pollution is prevented.

  When the concentration sensor 25 detects that the methane concentration in the fermenter 10 has reached a safe value, the control device stops the suction blower 30 and unlocks the door 11. The methane concentration (ratio of air to air) that measures the unlocking timing may be set to a value that has a sufficiently low risk of explosion and adverse effects on the human body. For example, it may be set to 5% or less, preferably 1% or less. When the lock is released, the fermentation residue is taken out from the open / close door 11 and new organic waste W is carried in again. What is necessary is just to process.

  In the present reference example, the biogas is stored in the gas pack 31, but the biogas can be stored in a storage tank capable of compressing and storing the biogas. In the first embodiment, part of the biogas is used as fuel for the gas engine type co-generator 32, but instead of the co-generator 32 or in addition to the co-generator 32. Then, a boiler or the like can be connected, and a part of the obtained biogas can be used as a fuel for the boiler or the like.

(Example)
2 to 4 show an embodiment of the organic waste treatment apparatus of the present invention. In FIG. 2, the state of the fermenter 40 in the anaerobic fermentation process is shown in section while schematically showing the overall configuration of the organic waste treatment apparatus. FIG. 3 is an enlarged cross-sectional view of a main part showing a state of the fermenter 40 in the opportunity fermentation (composting process). In the present Example, the point which uses the component-type (container type) fermenter 40 differs greatly from a reference example. Below, it demonstrates centering on a different structure from a reference example.

  As shown in FIGS. 2 and 3, the organic waste treatment apparatus includes a fermenter 40 in which the organic waste W is fermented and dried, and an air supply blower (blower unit) that blows air into the fermenter 40. 41, a machine room 50 provided below the fermenter 40, and input means 60 for introducing the organic waste W into the fermenter 40.

  The fermenter 40 is a vertically long cylindrical airtight container. The top wall 40r of the fermenter 40 is provided with an input port 42 for introducing the organic waste W and an exhaust port 43 for exhausting water vapor and gas generated in the fermenter 40. At the lower part of the peripheral wall 40 s of the fermenter 40, an outlet 44 for taking out the processed product out of the fermenter 40 is provided. The inlet 42 and the outlet 44 are provided with a shutter 45 that opens and closes them. The shutter 45 closes the inlet 42 and the outlet 44 so that the fermenter 40 is airtight. The shutter 45 may be opened and closed manually or by a control device. Moreover, it may be connected so that rotation is possible via a hinge, and it is good also as a slide opening-and-closing type. The charging port 42 is provided with a charging hopper 61 that facilitates the charging of the organic waste W.

  The fermenter 40 has a three-layer heat insulating structure having a heat insulating layer 40c between the metallic outer layer 40a and the metallic inner layer 40b. The heat insulating layer 40c is not particularly limited as long as it can exhibit heat insulating properties, and may be a glass wool layer, a rock wool layer, a foamed resin layer, a vacuum layer, or the like. You may combine these suitably. In this embodiment, the outer layer 40a and the inner layer 40b are made of steel, and the heat insulating layer 40c is a glass wool layer.

  In the fermenter 40, a rotating shaft 46 standing at the center and a plurality of stirring blades 47 extending radially from the rotating shaft 46 in the horizontal direction are arranged. The rotating shaft 46 has a hollow cylindrical shape and is provided so as to be rotatable. The rotating shaft 46 is longer than the height of the fermenter 40 and extends from the machine room 50 through the bottom wall 40d and the top wall 40r of the fermenter 40 to above the fermenter 40. A seal 70 is disposed at a portion where the rotating shaft 46 passes through the top wall 40r and the bottom wall 40d, and the airtightness of the fermenter 40 is ensured. The upper end of the rotating shaft 46 is covered with a cover box 71. The floor plate 15 having a plurality of pores 16 is disposed at a position above the bottom wall 40d by a predetermined amount, and the processing liquid S is stored in the underfloor space in the same manner as the fermenter 10 of the embodiment. .

  The agitation blade 47 is provided in a plurality of stages in the fermentation tank 40 from the lower part to the upper part of the rotating shaft 46. The lowermost stirring blade 47 is provided at a position above the bottom wall 40d of the fermentation tank 40 by a predetermined amount, and a predetermined amount of gap is provided between the lowermost stirring blade 47 and the bottom wall 40d of the fermentation tank 40. There is. As shown in FIG. 4, each stirring blade 47 includes a horizontal bottom plate 47a, a swash plate 47b joined obliquely upward from one side edge of the bottom plate 47a, and the other side edge of the bottom plate 47a and the swash plate 47b. This is a hollow member composed of a bent plate 47c joined to the other side edge. The swash plate 47 b is joined to the front side in the rotational direction of the stirring blade 47. The bent plate 47c has an L-shaped cross section in which an intermediate portion is bent so as to protrude toward the other side edge side of the bottom plate 47a (the rear side in the rotation direction of the stirring blade 47). As a result, each stirring blade 47 has a substantially mountain-shaped cross-sectional shape that protrudes upward, with one of the base corners dropped by the bent plate 47c. Further, a flange piece 47d that extends obliquely downward from the upper part of the bent part is joined to the bent plate 47c. The hollow space of each stirring blade 47 and the hollow space of the rotating shaft 46 are in communication.

  In addition, as shown in FIG. 3, among the stirring blades 47 provided in the upper and lower stages, the bent plate 47 c of the stirring blade 47 provided in the lower layer portion in the fermenter 40 including the lowermost stirring blade 47 is hollow. A vent hole 48 extending from the space to the outside is formed so as to penetrate inside and outside. The agitating blade 47 provided in the upper layer part in the fermenter 40 is not provided with a vent hole. In addition, the lower layer part in the fermenter 40 means a substantially lower half region in the fermenter 40. Moreover, the upper layer part in the fermenter 40 means a substantially upper half region in the fermenter 40. In the present embodiment, the air holes 48 are provided in the lowermost stage and the second stage stirring blade 47 from the bottom. A plurality of ventilation holes 48 are arranged in the longitudinal direction of the stirring blade 47, and the interval between the adjacent ventilation holes 48 gradually narrows from the base end (rotary shaft 46 side) to the distal end of the stirring blade 47. Yes. Further, as shown in FIG. 4, each vent hole 48 is provided below the bent portion of the bent plate 47c.

  As shown in FIG. 2, the air blower 41 which is a ventilation means is provided in both the downward direction and the upper direction of the fermenter 40. As shown in FIG. The lower air supply blower 41 is disposed in the machine room 50 and is connected to the lower end of the rotating shaft 46. On the other hand, the upper air supply blower 41 is placed on the fermenter 40 and is connected to the upper end of the rotating shaft 46. Precisely, it is connected to a cover box 71 that covers the upper end of the rotating shaft 46. As a result, air is blown to the rotary shaft 46 from the upper and lower air supply blowers 41 and 41. An exhaust pipe 34 is connected to the exhaust port 43. A suction blower 30 on the exhaust pipe 34 is also placed on the fermenter 40.

  In the machine chamber 50, a drive unit unit for rotating the rotary shaft 46 is disposed. The drive means unit includes a hydraulic cylinder 51 serving as a drive source and a gear 52 that meshes with the rotation shaft 46. The hydraulic cylinder 51 can be moved back and forth in the left-right direction. In response to the forward / backward movement of the hydraulic cylinder 51, the gear 52 is intermittently rotated in one direction by a cam member (feed claw) (not shown).

  The input means 60 includes a bucket 62 that conveys the organic waste W and a bucket elevator 63 that raises and lowers the bucket 62. The bucket elevator 63 is assembled adjacent to the fermenter 40 and extends to above the fermenter 40. The bucket 62 and the bucket elevator 63 are connected by a wire 64, and a winding drum 65 for winding the wire 64 is provided at the upper end of the bucket elevator 63. Although not shown, the bucket elevator 63 is provided with a rail, and rollers provided on the left and right side surfaces of the bucket 62 are slidably fitted in the rail. Usually, the bucket 62 is located at the lower end of the bucket elevator 63. When the wire 64 is taken up by driving the take-up drum 65, the lower bucket 62 is pulled, and the bucket 62 is lifted up along the rail. When the bucket 62 reaches the upper end of the bucket elevator 63, the bucket 62 tilts and the organic waste W inside is thrown in.

  In this embodiment, as a storage means for storing the obtained biogas, a gas storage tank 38 capable of compressing and storing biogas is used instead of the gas pack 31 of the reference example. Moreover, since the fermenter 40 of a present Example is a heat insulation tank, the heat piping like a reference example is not provided. However, it is also preferable to embed a heat pipe in the heat insulating layer 40c of the fermenter 40. The point which has the gas engine type generator 32 which produces electric power using biogas, and the biofilter 33 which purifies unnecessary gas is the same as that of a reference example. An exhaust pipe 34 is connected in a branched manner from the exhaust port 12 to the gas storage tank 38 and the biofilter 33, and the biogas is switched between the gas storage tank 38 and the biofilter 33 at the branch point of the exhaust pipe 34. A three-way valve 35 for supplying air is provided.

  In the present embodiment, the fermentation residue after the organic waste W is subjected to anaerobic fermentation is fermented together with aerobic microorganisms in an aerobic environment and composted. The aerobic microorganism for that purpose is preferably an aerobic microorganism that can be activated (proliferated) at about 30 to 90 ° C. This is because drying of organic waste can be promoted by utilizing the temperature rise accompanying fermentation. Examples of such aerobic microorganisms include genus Geobatisul and Bacillus. Specifically, Geobacillus as a bacterium of the genus Geobacillus. Geobacillus thermodenitrificans, Geobacillus. Steobaothermophilus (Geobacillus stearothermophilus), Geobacillus. Coastophilus (Geobacillus kaustophilus), Geobacillus. Geobacillus subterranens, Geobacillus. Thermobavorans, Geobacillus. Examples include Cardobasilus caldoxylosilyticas. Moreover, as a bacterium of the genus Bacillus, Bacillus sp. TAT105 (Bacillus sp. TAT105), Bacillus sp. And TAT112 (Bacillus sp. TAT112). Among them, Geobacillus. Thermodenitificans and Geobacillus. Cardoxio silicicus is preferred. These aerobic microorganisms may be used alone or in combination of two or more.

  Next, the processing of the organic waste by the fermentation drying apparatus will be described. First, a predetermined amount of organic waste W is introduced into the fermenter 40 using the bucket 62, the shutter 45 is closed, and the fermenter 40 is airtight. At this time, naturally, the outlet 44 is also closed by the shutter 45. Then, while stirring with each stirring blade 47, the organic waste W is subjected to anaerobic fermentation in the same manner as in the reference example to recover biogas (see FIG. 2). At this time, the air supply blower 41 is not driven. When the hydraulic cylinder 51 is driven, the rotating shaft 46 is pivoted intermittently in one direction. Since each stirring blade 47 has a substantially mountain shape having a swash plate 47b on the front side in the rotation direction, the stirring efficiency of the organic waste W is higher than that of the flat stirring blade. In addition, since each air vent 48 is provided on the rear side in the rotation direction, and the flange 47d is provided above each air vent 48, each air vent 48 is not easily clogged by the organic waste W.

  When the organic waste W is sufficiently anaerobically fermented, the fermentation residue is subsequently fermented under aerobic conditions to be composted. For this purpose, after the anaerobic fermentation, the pumping pump 18 is stopped, and then the inlet 42 is opened, and a treatment liquid or a fungus bed (seed compost) containing aerobic microorganisms is introduced into the fermenter 40. In addition, even if the aerobic microorganisms are charged, the rotating shaft 46 can be driven uniformly by driving. Then, after closing the inlet 42 again, the upper and lower air supply blowers 41 and 41 are driven. Thus, as shown in FIG. 3, the fermentation residue is composted by aerobic fermentation while being constantly aerated, and is also dried. Specifically, the air supplied to the rotating shaft 46 is blown into the fermenter 40 from the vent holes 48 of the lowermost stage and the second stage stirring blade 47 from the bottom. The air flows upward in the fermenter 40 while passing through the fermentation residue, and is actively exhausted from the exhaust port 43 together with odor and water vapor generated from the fermentation residue. The gas exhausted from the exhaust port 43 is released into the atmosphere through the biofilter 33. In addition, since the air supplied from the air supply blower 41 is blown out from the stirring blade 47 rotating around the rotation shaft 46, the air can be uniformly vented over the entire fermenter 40. When the fermentation residue is subjected to aerobic fermentation, the temperature is raised to about 40 to 80 ° C. (fermentation treatment step). At this time, since the fermenter 40 is an insulated container, the temperature rise state is maintained well. Moreover, generation | occurrence | production of dew condensation water can be effectively suppressed by interrupting | blocking the temperature difference with external air. And water evaporation in a fermentation residue is accelerated | stimulated by heating up with fermentation heat.

  According to the fermenter 40 of the present embodiment, the heat of fermentation can be effectively used for water evaporation, so that the drying time can be shortened and a significant increase in energy cost can be avoided. Moreover, the device itself has a simple structure. When the fermentation process and the drying process are completed, the outlet 44 is opened to take out the organic waste that has been dried into compost. This compost can be reused as fertilizer and soil conditioner in agriculture and horticulture.

  In the present embodiment, the blower blowers 41 are provided above and below the fermenter 40, but only one blower blower 41 connected to at least the lower end of the rotating shaft 46 may be provided. Others are the same as in the reference example, so the same reference numerals are assigned to the same members, and a detailed description is omitted.

10.40 Fermenter 11. Opening door 12.43 Exhaust port 13. Ventilation window 15. Floor plate 18. Pumping pump 19. Injection nozzle 22. Thermal piping 25. Concentration sensor 30. Suction blower 31. Gas pack 32. Co-generator (gas engine generator).
33 Biofilter 34 Exhaust pipe 35 Three-way valve 36 Heat exchanger 41 Air blower 46 Rotating shaft 47 Stirrer blade 48 Ventilation hole 50 Machine room 61 Input hopper 62 Bucket 63 Bucket elevator G Ground S Treatment liquid W Organic waste M Purifier

Claims (4)

A fermenter capable of maintaining an airtight state, a pump including a methanogenic bacterium that generates methane by anaerobic fermentation of organic waste, and a treatment pumped by the pump. An organic waste treatment apparatus for obtaining a biogas by anaerobically fermenting organic waste in the fermentor, having an injection nozzle for injecting a liquid from an upper part of the fermenter,
A floor plate having a plurality of pores is disposed at an upper position from the bottom wall of the fermenter,
The organic waste is deposited on the floorboard and fermented,
The treatment liquid is stored in a lower space of the floor board,
The fermenter is a component-type fermenter comprising a rotating shaft erected in such a manner that the shaft can rotate and a stirring blade provided around the rotating shaft,
An air supply means is connected to the fermentor,
After the organic waste is anaerobically fermented in an airtight state while driving the pumping pump, the pumping pump is stopped, and then the fermentation residue after the anaerobic fermentation is left as it is while driving the air feeding means. Organic waste treatment equipment capable of aerobic fermentation. The rotating shaft is a hollow cylinder, and the air supply means is connected to a lower end portion of the rotating shaft,
The stirring blade is provided in a plurality of upper and lower stages around the rotating shaft,
Among the plurality of stirrer blades, at least the lowest stirrer blade is hollow, and a plurality of vent holes are formed so as to penetrate inside and outside,
The organic waste according to claim 1, wherein when the fermentation residue is subjected to aerobic fermentation, the air fed from the air feeding means is fed from the lower part of the fermenter via the vent of the stirring blade. Processing equipment. The stirring blade has a substantially mountain shape having a swash plate on the front side in the rotation direction,
The vent hole is provided on the rear side in the rotation direction,
The organic waste treatment apparatus according to claim 2, wherein a flange piece is provided above the vent hole. A fermenter capable of maintaining an airtight state, a pump for pumping up a processing liquid containing methanogenic bacteria that generates organic methane by anaerobic fermentation of organic waste, and a processing liquid pumped up by the pump An injection nozzle for injecting from the upper part of the fermenter, a floor plate having a plurality of pores arranged at an upper position from the bottom wall of the fermenter, and an air supply means connected to the fermenter The fermenter is a component-type fermenter comprising a rotating shaft erected in such a manner that the shaft can rotate and a stirring blade provided around the rotating shaft. An organic waste fermentation method for fermenting the organic waste by an organic waste treatment device stored in a lower space,
After the organic waste is anaerobically fermented in an airtight state while driving the pumping pump, the pumping pump is stopped, and then the fermentation residue after the anaerobic fermentation is left as it is while driving the air feeding means. A method for fermenting organic waste, in which aerobic fermentation is performed.

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