JP2008029983A - Biogas generating system, thermal cracking gas generating system, biogas and thermal cracking gas generating system, and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biogas generating system and its method easily enhancing a desulfurization efficiency of a fuel gas such as a biogas and a thermal cracking gas, developing the effect exceeding a cost up therefor, and saving a construction cost caused by miniaturization of a desulfurization plant. <P>SOLUTION: The biogas generating system is provided with a fermenting vessel 3 generating a biogas 1 by making organic waste ferment, a first biological desulfurizing plant 5A fed with the biogas 1 from the fermenting vessel 3 and performing biological desulfurization of the biogas 1, a first temperature control means making the temperature of the biological desulfurizing plant 5A 50-90°C by heating a fermented liquid 2 which is partially taken out from the fermenting vessel 3 and by feeding it into the first biological desulfurizing plant 5A, and a first condensing device 17A recovering a condensate by cooling the biogas 1 fed from the first biological desulfurizing plant 5A to the rear stage of the first biological desulfurizing plant 5A. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a biodesulfurization apparatus and method for performing biodesulfurization treatment on a fuel gas containing a sulfur compound such as hydrogen sulfide, a fermenter for fermenting organic waste to produce biogas, and the fermenter The present invention relates to a biogas generation system and method including a biodesulfurization apparatus that sends the biogas from and supplies a biodesulfurization treatment to the biogas.

  Hydrogen sulfide is usually contained in biogas produced by fermenting organic waste such as livestock waste and garbage in a fermenter. For example, biogas for methane fermentation typically contains about 50 to 60% by volume of methane gas, about 40 to 50% by volume of carbon dioxide, and about 0.2% by volume of hydrogen sulfide.

  The biological desulfurization apparatus is provided to oxidize and remove the hydrogen sulfide in the biogas from near neutrality to sulfuric acid on the alkaline side to produce purified biogas. The sulfur-oxidizing bacteria in the biological desulfurization apparatus oxidize hydrogen sulfide to sulfuric acid, but in order to activate the sulfur-oxidizing bacteria, it is necessary to contact with water containing nutrient components. This water comes into circulation contact with sulfur-oxidizing bacteria in the tower through a circulation line.

  The temperature in the biological desulfurization apparatus is conventionally set in the range of 30 to 80 ° C. (for example, Patent Document 1). In particular, depending on the acclimatization conditions, the activity of sulfur-oxidizing bacteria becomes active in a temperature range of 40 to 60 ° C., and a good desulfurization effect is obtained.

JP 2005-95783 A

  In the research intended to increase the desulfurization performance and make the biological desulfurization apparatus more compact, the present inventors heated a part of the fermentation broth and sent it into the biodesulfurization apparatus, so that the desulfurization treatment in the biodesulfurization apparatus It has been found that the desulfurization efficiency can be improved by increasing the temperature, and this effect can offset the increase in cost for increasing the temperature of the fermentation broth. The present invention has been made in such a background, and its purpose is to easily increase the desulfurization efficiency of fuel gas such as biogas and pyrolysis gas, and to express the effect of increasing the cost for high temperature. It is to provide a generation system and method.

  In order to achieve the above object, the biogas generation system according to the first aspect of the present invention includes a fermenter that ferments organic waste to generate biogas, and the biogas is sent from the fermentor. A first biological desulfurization apparatus that performs a biological desulfurization treatment on the biogas, and a first portion of the first biological desulfurization apparatus that is heated and sent to the first biological desulfurization apparatus A first temperature adjusting means for bringing the inside of the biological desulfurization apparatus to a temperature of 50 ° C. to 90 ° C. and a biogas sent from the first biological desulfurization apparatus downstream of the first biological desulfurization apparatus to cool the condensate And a first condensing device for collecting the water.

  According to the present invention, when biodesulfurization treatment is performed on a biogas containing a sulfur compound such as hydrogen sulfide at a temperature of 50 ° C. to 90 ° C., the desulfurization is performed by sufficiently acclimatizing to high temperature. Efficiency improvement and performance can be maintained, and high-quality purified biogas can be obtained efficiently. Efficient desulfurization by increasing the temperature can reduce the construction cost by downsizing the first biological desulfurization apparatus. Biogas can be used as a fuel for the energy required for increasing the temperature of the fermentation broth. In the case of a fermentation broth by high-temperature fermentation, the required energy is small and economical.

Furthermore, by heating a part of the fermentation broth and sending it to the first biological desulfurization apparatus, the temperature inside the first biological desulfurization apparatus can be increased efficiently, and the temperature of the fermentation broth increases. Evaporation also occurs, and ammonia contained in the fermentation broth is also released out of the liquor. That is, in the first biological desulfurization apparatus, water vapor and ammonia increase in addition to the conventional biogas.
And since the 1st condensing apparatus which cools the biogas sent from this biodesulfurization apparatus and collect | recovers condensate is further provided in the back | latter stage of said 1st biodesulfurization apparatus, high quality refinement | purification biogas is obtained. And ammonia can be recovered along with the condensate. The recovered ammonia can be reused.

  A pyrolysis gas generation system according to a second aspect of the present invention includes a pyrolysis furnace that generates pyrolysis gas by heating waste to be pyrolyzed, and the pyrolysis gas is sent from the pyrolysis furnace, A second biological desulfurization apparatus that performs biological desulfurization treatment on the pyrolysis gas and a fermentation liquid partially taken out from a fermenter that ferments organic waste are heated and sent to the second biological desulfurization apparatus. By means of a second temperature adjusting means for bringing the inside of the second biological desulfurization apparatus to a temperature of 50 ° C. to 90 ° C., and thermal decomposition sent from the second biological desulfurization apparatus to the subsequent stage of the second biological desulfurization apparatus And a second condensing device for recovering the condensate by cooling the gas.

  According to the present invention, by using a fermented liquid of organic waste that is originally treated as waste, the inside of the second biological desulfurization apparatus is set to a temperature of 50 ° C. to 90 ° C., and improvement of desulfurization efficiency and performance are maintained. Thus, high-quality purified biogas can be obtained efficiently. Efficient desulfurization by increasing the temperature can reduce the construction cost by downsizing the second biological desulfurization apparatus. The energy required for increasing the temperature of the fermentation broth can use pyrolysis gas as fuel. In the case of a fermentation broth by high-temperature fermentation, the required energy is small and economical.

  Moreover, while heating a part of fermentation liquid and sending it in a 2nd biological desulfurization apparatus similarly to a 1st aspect, while being able to efficiently heat up the inside of a 2nd biological desulfurization apparatus, By the second condensing device provided after the second biological desulfurization device, it is possible to recover the ammonia released from the high temperature of the fermentation broth. The recovered ammonia can be reused.

  The biogas and pyrolysis gas generation system according to the third aspect of the present invention includes a fermenter for fermenting organic waste to generate biogas, the biogas sent from the fermentor, and the biogas A first biological desulfurization apparatus that performs a biological desulfurization process on the first and the second biological desulfurization apparatus by heating the fermentation liquor partially taken out from the fermenter and feeding it into the first biological desulfurization apparatus A first temperature adjusting means for setting the inside to a temperature of 50 ° C. to 90 ° C. and a biogas sent from the first biological desulfurization device after the first biological desulfurization device are cooled to recover a condensate. A biogas generation system comprising: a first condensing device; a pyrolysis furnace that generates pyrolysis gas by heating waste to be pyrolyzed; and the pyrolysis gas is sent from the pyrolysis furnace, A second type of biodesulfurization treatment for pyrolysis gas The inside of the second biological desulfurization apparatus is set to a temperature of 50 ° C. to 90 ° C. by heating the product desulfurization apparatus and the fermentation liquid partially taken out from the fermenter and sending it to the second biological desulfurization apparatus. A second temperature adjusting means; and a second condensing device for recovering a condensate by cooling a pyrolysis gas sent from the second biodesulfurizing device after the second biodesulfurizing device. And a pyrolysis gas generation system.

  According to the present invention, in addition to utilizing the fermentation broth of the biogas generation system for increasing the temperature of the first biodesulfurization device of the biogas generation system, the second biodesulfurization of the pyrolysis generation system In order to utilize also for the high temperature of an apparatus, the fermentation liquid originally processed as a waste in the said biogas production | generation system can be utilized effectively. And the ammonia contained in this fermentation liquid can be collect | recovered in the 1st condensing apparatus of a biogas production | generation system, and the 2nd condensing apparatus of a pyrolysis gas production | generation system, and more ammonia condensates are collect | recovered. be able to. By these things, the running cost as the whole biogas and thermal decomposition production system can be held down.

In the biogas production method according to the fourth aspect of the present invention, organic waste is fermented in a fermentor to produce biogas, and the biogas is passed through a first biological desulfurization apparatus to perform desulfurization treatment. A biogas production method for producing purified biogas,
When biodesulfurization treatment is performed on the biogas, the fermentation liquor partially taken out from the fermenter is heated and sent into the first biodesulfurization apparatus to be treated at a temperature of 50 ° C. to 90 ° C. Then, the biogas that has undergone the biological desulfurization treatment process is cooled to recover the condensate. Thereby, the same effect as a 1st aspect can be acquired.

  In the pyrolysis gas generation method according to the fifth aspect of the present invention, the pyrolysis target waste is heated to generate pyrolysis gas, and the pyrolysis gas is passed through the second biological desulfurization apparatus to perform desulfurization treatment. A pyrolysis gas generation method for generating a purified pyrolysis gas, wherein when the biodesulfurization treatment is performed on the pyrolysis gas, the fermentation liquor partially taken out from the fermenter for fermenting organic waste is heated. And is sent to the second biological desulfurization apparatus so as to be treated at a temperature of 50 ° C. to 90 ° C., and the pyrolysis gas that has undergone the biological desulfurization treatment process is cooled to recover the condensate. It is. Thereby, the same effect as the 2nd mode can be obtained.

  In the biogas and pyrolysis gas production method according to the sixth aspect of the present invention, organic waste is fermented in a fermentor to produce biogas, and the biogas is passed through a first biodesulfurization apparatus to desulfurize. A biogas generation method for generating purified biogas by performing a treatment, wherein when the biodesulfurization process is performed on the biogas, the first organism is heated by heating a fermentation liquid partially taken out from the fermenter By sending it into the desulfurization unit, it is treated at a temperature of 50 ° C. to 90 ° C., the biogas generation step for cooling the biogas that has undergone the biological desulfurization treatment step and collecting the condensate, and heating the waste subject to pyrolysis A pyrolysis gas is generated, and the pyrolysis gas is passed through a second biological desulfurization apparatus to perform a desulfurization process so as to generate a purified pyrolysis gas. To perform biological desulfurization treatment Then, the fermented liquor partially taken out from the fermenter is heated and sent into the second biological desulfurization apparatus, so that it is processed at a temperature of 50 ° C. to 90 ° C. and undergoes a biological desulfurization treatment step. And a pyrolysis gas generation step characterized by recovering the condensate by cooling. Thereby, the same effect as the 3rd mode can be obtained.

According to the present invention, by heating a part of the fermentation broth and sending it into the biological desulfurization apparatus, the temperature in the biological desulfurization apparatus can be efficiently increased.
Further, a device equipped with a condensing device for cooling the biogas or pyrolysis gas sent from the biodesulfurization device and recovering the condensate at the subsequent stage of the biodesulfurization device is provided with a high-quality purified biogas or pyrolysis gas. Ammonia can be recovered along with the condensate.

[Example 1]
An embodiment of a biogas generation system including a biodesulfurization apparatus that performs biodesulfurization processing on biogas containing a sulfur compound will be described in detail with reference to FIG. FIG. 1 is a schematic configuration diagram showing an aspect of a biogas generation system according to the present invention. In general, examples of the sulfur compound include carbon disulfide, carbonyl sulfide, mercaptans, alkyl sulfides and the like in addition to hydrogen sulfide, but in the case of biogas, hydrogen sulfide and mercaptans are mainly used.

  Biogas includes methane fermentation and hydrogen fermentation, and the present invention can be similarly applied to each of these fermentations. In the following description, a biogas generation system based on methane fermentation will be described. However, a biogas generation system based on hydrogen fermentation is almost the same process or system.

  The biogas generation system of FIG. 1 includes, as main components, a fermenter 3 in which biomass, that is, organic waste, is sent to ferment the organic waste to produce biogas 1 and fermentation broth 2, The biogas 1 is sent from the fermenter 3 through the biogas line 4, and the biogas 1 is brought into contact with sulfur-oxidizing bacteria, and a first biodesulfurization apparatus 5A that performs biodesulfurization treatment is provided.

  Furthermore, the element which comprises the 1st temperature control means which heats the fermented liquor 7 and heats it to the supply line 6 for sending the fermented liquor 7 extracted partially from the fermenter 3 in the 1st biological desulfurization apparatus 5A. 8A, which is one of the above. The heating device 8A heats the fermentation broth 7 as a heat source so that the desulfurization temperature in the first biological desulfurization device 5A is 50 ° C. to 90 ° C., and biogas cogeneration not shown in the present embodiment. It is comprised with the heat exchanger using the hot water (about 80 degreeC or more). Of course, other heating devices such as a boiler using biogas may be used.

  The high-temperature fermentation broth 9 heated by the heating device 8A is sent to the circulation tank 11A via the line 10 and stored. The high-temperature fermentation liquid 9 in the circulating liquid tank 11A is sent to the spraying part 13A in the first biological desulfurization apparatus 5A via the introduction line 12A, and from the spraying part 13A into the apparatus 5A in a shower shape. The liquid is sprayed and returned to the circulating fluid tank 11A via the return line 22A. Reference numeral 21A denotes a circulation pump.

  As described above, the high-temperature fermentation broth 9 circulates in the first biological desulfurization apparatus 5A as a circulating liquid so that the temperature is 50 ° C. to 90 ° C., and the sulfur supported on the support portion 14. Continuous contact with the oxidizing bacteria 15. As a result, the sulfur-oxidizing bacteria 15 are activated and act on the hydrogen sulfide in the biogas 1 sent from the biogas line 4 into the apparatus 5A to oxidize it to sulfuric acid. That is, the first temperature adjusting means includes the heating device 8A, the circulating fluid tank 11A, the introduction line 12A, the spraying portion 13A, the circulating pump 21A, and the return line 22A.

Reference numeral 16A denotes an air supply unit. Air is supplied from the air supply unit 16A into the biogas 1, and in this state, the biogas 1 is sent into the first biodesulfurization apparatus 5A to create an aerobic environment. Yes. Specifically, the biogas 1 is held in the first biological desulfurization apparatus 5A for 1 minute or more, preferably 3 minutes or more, and the flow rate L (liters) of the high-temperature fermentation broth 9 with respect to the supply flow rate G (m ³ ) of the biogas 1. ) Is set to 0.1 to 100, preferably 1 to 50. The first biological desulfurization apparatus 5A has a known packed tower or plate tower structure.

  A part of the high-temperature fermentation broth 9 that has become the circulating liquid is extracted from the bottom of the circulating liquid tank 11 into the slurry tank 18 via the extraction line 19. Also, most of the fermentation liquor 2 is extracted from the bottom of the fermenter 3 and sent to the slurry tank 18 via the line 20 and is stored in the slurry tank 18 for several months.

  A first condensing device 17A that cools the biogas 1 sent from the biodesulfurization device 5A and collects the condensate is provided downstream of the first biodesulfurization device 5A. The first condensing device 17A is configured by a known air cooling type or water cooling type.

  As for the fermenter 3, organic waste is supplied in a tank from a supply part (not shown). The organic waste is methane-fermented by methane-fermenting bacteria in an anaerobic atmosphere in the fermenter 3 to produce biogas 1 and fermentation broth 2. The temperature in the fermenter 3 is set to 55 ° C., and high-temperature methane fermentation is performed. The residence time of the organic waste in the fermenter 3 is set to, for example, 15 days (tank volume / injection / extraction amount = 15 days). The temperature in the fermenter 3 may be lower than 55 degreeC, for example, 37 degreeC may be sufficient.

  Examples of the organic waste (biomass) used in this embodiment include garbage, wastewater treatment sludge, livestock waste, and green farm waste. Here, livestock waste includes livestock manure, carcass, and processed products thereof. More specifically, livestock manure such as pigs, cattle, sheep, goats, chickens, and carcasses thereof, and Processed products such as meat-and-bone meal, meat meal, bone meal, and blood meal are also included. Examples of other waste include household waste, industrial waste, agricultural and marine industrial waste, food processing waste, and the like. Depending on the state of the organic waste, a step of crushing, separating and solubilizing as a pretreatment can be performed as necessary.

Next, the operation of the above embodiment will be described.
According to the present invention, biodesulfurization treatment is performed on a biogas 1 containing a sulfur compound such as hydrogen sulfide at a temperature of 50 ° C. to 90 ° C., and sufficient acclimatization to a high temperature is performed, thereby improving the desulfurization efficiency. Improvement and performance can be maintained, and high-quality purified biogas can be efficiently obtained. Efficient desulfurization by increasing the temperature can reduce the construction cost by downsizing the desulfurization equipment. In the case of high-temperature fermentation, the energy required to obtain the high-temperature fermentation solution 9 is small and economical.

Furthermore, by heating a portion of the fermentation broth 2 and sending the high-temperature fermentation broth 9 into the first biological desulfurization apparatus 5A, the inside of the first biological desulfurization apparatus 5A can be efficiently heated, As the temperature of the fermentation broth 2 increases, the liquid also evaporates, and the ammonia contained in the fermentation broth 2 is also diffused out of the liquor. That is, in the first biological desulfurization apparatus 5A, steam and ammonia increase in addition to the conventional biogas 1.
And since the 1st condensation apparatus 17A which cools the biogas 1 sent from this biological desulfurization apparatus 5A and collect | recovers condensate is further provided in the back | latter stage of said 1st biological desulfurization apparatus 5A, high quality refinement | purification Biogas can be obtained and ammonia can be recovered together with the condensate. The recovered ammonia can be reused.

[Example 2]
An embodiment of a pyrolysis gas generation system including a biodesulfurization apparatus that performs biodesulfurization treatment on a pyrolysis gas containing a sulfur compound will be described in detail with reference to FIG. FIG. 2 is a schematic configuration diagram showing an aspect of the pyrolysis gas generation system according to the present invention. Examples of the sulfur compound include carbon disulfide, carbonyl sulfide, mercaptans, alkyl sulfides and the like in addition to hydrogen sulfide, and the composition of each component varies depending on the type of the substance to be decomposed. For example, in the case of tire pyrolysis, hydrogen sulfide, carbonyl sulfide, and the like are generated as sulfur compounds. Examples of substances to be decomposed include waste tires, waste plastics, synthetic resins, and garbage. Particularly, organic polymer compounds such as waste tires, waste plastics, and synthetic resins generate high-concentration sulfur-containing pyrolysis gas.

  The pyrolysis gas generation system shown in FIG. 2 includes, as main components, a pyrolysis furnace 33 that heats and thermally decomposes waste to be pyrolyzed to generate pyrolysis gas 31, and pyrolysis from the pyrolysis furnace 33. A pyrolysis gas 31 is sent through the gas line 34, and a second biodesulfurization apparatus 5B is provided that performs biodesulfurization treatment by bringing the pyrolysis gas 31 into contact with sulfur-oxidizing bacteria. Reference numeral 32 indicates a thermal decomposition residue.

  Furthermore, a biomass, that is, an organic waste is sent to the fermenter 43 for fermenting the organic waste, and a fermentation liquid 7 partially taken out from the fermenter 43 is sent into the second biological desulfurization apparatus 5B. The supply line 6 is provided with a heating device 8B which is one of elements constituting second temperature adjusting means for heating the fermentation broth 7 to increase the temperature. Instead of the fermenter 43, the fermented liquid of the organic waste discharged | emitted in the adjacent organic waste processing facility may be stored and installed in a tank etc. Since the configuration of the heating device 8B is the same as that of the first embodiment, detailed description thereof is omitted.

  The high-temperature fermentation broth 9 heated by the heating device 8B is sent to the circulation tank 11B via the line 10 and stored. The high-temperature fermentation broth 9 in the circulating liquid tank 11B is sent to the spraying part 13B in the biological desulfurization apparatus 5 via the introduction line 12B, and is sprayed into the apparatus 5B from the spraying part 13B. , The fluid is returned to the circulating fluid tank 11B via the return line 22B. Reference numeral 21B denotes a circulation pump.

As described above, by using the fermented liquid 42 of organic waste that is originally processed as waste, the temperature in the second biological desulfurization apparatus 5B is set to 50 ° C. to 90 ° C., and is supported on the support portion 14. The sulfur-oxidizing bacteria 15 that are present oxidize hydrogen sulfide or the like in the pyrolysis gas 31 to sulfuric acid. That is, it is configured to include a heating device 8B, a circulating liquid tank 11B, an introduction line 12B, a spraying part 13B, a circulating pump 21B, and a return line 22B.
Reference numeral 16B denotes an air supply unit that supplies air into the pyrolysis gas 31 in order to create an aerobic environment in the second biological desulfurization apparatus 5B.

A second condensing device 17B that cools the pyrolysis gas 31 sent from the biodesulfurization device 5B and collects the condensate is provided at the subsequent stage of the second biodesulfurization device 5B.
The amount of the high-temperature fermentation solution 9 circulated in the second biological desulfurization apparatus 5B, the fermentation strip conditions in the fermentation tank 43, and the configuration in which the high-temperature fermentation solution 9 and the fermentation solution 42 are sent to the slurry tank 18 and stored are as follows. Since it is the same as that of Example 1, the detailed description is abbreviate | omitted.

Examples of the pyrolysis target waste used for generating the pyrolysis gas in this embodiment include waste tires, waste plastics, synthetic resins, and garbage. Depending on the state of the waste to be pyrolyzed, it is desirable to perform treatment by a crushing and separating device (not shown) as pretreatment as necessary. By the crushing / separation process, the pyrolysis target waste can be crushed into a suitable size, and a portion that is not pyrolyzed can be separated.
Examples of organic waste (biomass) to be fermented in the fermenter 43 include the same garbage, wastewater treatment sludge, livestock waste, and green farm waste as in Example 1.

Next, the operation of the above embodiment will be described.
According to the present embodiment, the same action as that of the biogas 1 in the first embodiment can be obtained with respect to the pyrolysis gas 31 containing a sulfur compound such as hydrogen sulfide. Can be obtained. In addition, efficient desulfurization by increasing the temperature can reduce the construction cost by downsizing the desulfurization apparatus.
Similarly to the case of Example 1, a part of the fermentation broth 42 is heated to send the high-temperature fermentation broth 9 into the second biological desulfurization apparatus 5B, so that the temperature in the biological desulfurization apparatus 5B is efficiently increased. In addition, the ammonia diffused from the high-temperature fermentation broth 9 can be recovered by the condensing device 17 provided after the second biological desulfurization device 5B. The recovered ammonia can be reused. Moreover, since the fermentation liquid 42 originally treated as waste can be used effectively, the running cost of the entire pyrolysis gas generation system can be kept low.

[Example 3]
FIG. 3 is a schematic configuration diagram showing a biogas and pyrolysis gas generation system according to an embodiment of the present invention.
In this embodiment, a biogas generation system and a pyrolysis gas generation system are provided, and the fermentation liquid 2 of the biogas generation system is used for increasing the temperature of the second biodesulfurization device 5B of the pyrolysis generation system. It is configured.

  Furthermore, the heating apparatus which heats the fermentation liquid 7 and heats it to the supply line 6 for sending the fermentation liquid 7 partly taken out from the fermenter 3 to the first biological desulfurization apparatus 5A and the second biological desulfurization apparatus 5B. 8A is provided. The high-temperature fermentation broth 9 heated by the heating device 8A is sent to the circulation tank 11A via the line 10 and stored. In the circulation tank 11A, an introduction line 12A for sending the high-temperature fermentation liquor 9 to the first biodesulfurization apparatus 5A for biogas, and a high-temperature fermentation liquor 9 to the second biodesulfurization apparatus 5B for pyrolysis gas are provided. An introduction line 12B for sending is provided.

  The high-temperature fermentation liquid 9 in the circulating liquid tank 11A is sent to the spraying part 13A in the first biodesulfurization apparatus 5A for biogas via the introduction line 12A, and the biodesulfurization apparatus is sent from the spraying part 13A. The liquid is sprayed in the form of a shower in 5A and returned to the circulating fluid tank 11A via the return line 22A. Further, the high-temperature fermentation liquid 9 in the circulating liquid tank 11A is sent to the spraying part 13B in the second biological desulfurization device 5B for pyrolysis gas via the introduction line 12B, and the spraying part 13B It is sprayed in the form of a shower in the biological desulfurization apparatus 5B and returned to the circulating fluid tank 11A via the return line 22B. Reference numerals 21A and 21B denote circulation pumps.

In this way, the high-temperature fermentation broth 9 can be circulated in the first biological desulfurization apparatus 5A and the second biological desulfurization apparatus 5B, and the temperature thereof can be set to 50 ° C to 90 ° C. That is, the first temperature adjusting means for the biogas generation system includes the heating device 8A, the circulating liquid tank 11A, the introduction line 12A, the spraying part 13A, the circulating pump 21A, and the return line 22A. . The second temperature adjusting means for the pyrolysis gas generation system includes a heating device 8A and a circulating liquid tank 11A that are also used as the first temperature adjusting means, an introduction line 12B, a spraying part 13B, and a circulation pump. 21B and a return line 22B.
Reference numerals 16A and 16B denote air supply units that supply air into the biogas 1 or the pyrolysis gas 31 in order to create an aerobic environment in the biological desulfurization apparatuses 5A and 5B.

  A first condensing device 17A that cools the biogas 1 sent from the biodesulfurization device 5A and collects the condensate is provided at the subsequent stage of the first biodesulfurization device 5A. A second condensing device 17B that cools the pyrolysis gas 31 sent from the biodesulfurization device 5B and collects the condensate is provided at the subsequent stage of the second biodesulfurization device 5B.

  Thus, in addition to using the fermentation liquor 2 of the biogas generation system for increasing the temperature of the first biological desulfurization device 5A of the biogas generation system, the second organism of the pyrolysis gas generation system By utilizing it also for increasing the temperature of the desulfurization apparatus 5B, it is possible to effectively use the fermentation liquid 2 of the biogas generation system that is originally treated as waste, and the ammonia contained in the fermentation liquid 2 can be used. Since it can also collect | recover in a pyrolysis production | generation system, the running cost as the whole biogas production | generation and pyrolysis gas production | generation system can be held down low.

[Example 4]
The biogas plant according to the present embodiment is a facility that processes 4 t / day. The biogas plant is constituted by a biogas generation system shown in FIG. The biomass (milking cow manure) fermenter 3 had a capacity of 60 m ³ , the fermentation liquid 2 was extracted from the fermenter 3 at 4 t / day, and the biogas was extracted at 140 m ³ / day. The composition of the biogas averaged 55% by volume of methane gas, 45% by volume of carbon dioxide, and 1,500 ppm of hydrogen sulfide. The amount of circulating liquid in the biological desulfurization apparatus 5 was intermittent circulation (circulated at 50 L / min for 10 minutes and stopped for 20 minutes). The temperature of the high-temperature fermentation broth 9 sent into the biological desulfurization apparatus 5 was changed, and the concentration of hydrogen sulfide in the purified biogas was measured. The results are shown in Table 1.

  The concentration of hydrogen sulfide in the purified biogas is 15 ppm when the temperature of the high-temperature fermentation broth 9 measured from the temperature in the circulating liquid tank 11A is 50 ° C, 5ppm when 75 ° C, and 0.0ppm when 85 ° C. Met. As a comparative example, the concentration of hydrogen sulfide in the purified biogas when the temperature of the fermentation broth was 30 ° C. and 40 ° C. was 250 ppm and 50 ppm, respectively.

  The amount of the condensate obtained by the condenser 17A is 5 L / min, 10 L / min, respectively, when the temperature of the high-temperature fermentation broth 9 measured from the temperature in the circulating liquid tank 11A is 50 ° C., 75 ° C., and 85 ° C. 20 L / min.

Recovery of ammonia in aggregating agent, the temperature is 50 ° C. hot fermentation liquid 9 as measured from the temperature of the circulating fluid tank 11A, 75 ° C., during 85 ° C., respectively in the _NH ^{4 +} amount, 780 mg / L, They were 1800 mg / L and 3500 mg / L.

  The present invention includes a fermenter that ferments organic waste to produce biogas, and a biodesulfurization device that sends the biogas from the fermenter and performs biodesulfurization treatment on the biogas. The present invention can be used for biogas generation systems and methods. Further, a pyrolysis furnace that pyrolyzes organic waste to generate pyrolysis gas, and a biodesulfurization apparatus that sends the pyrolysis gas from the pyrolysis furnace and performs biodesulfurization treatment on the pyrolysis gas Can be used in a pyrolysis gas generation system and method.

It is a schematic block diagram which shows the biogas production | generation system which concerns on one embodiment of this invention. 1 is a schematic configuration diagram showing a pyrolysis gas generation system according to an embodiment of the present invention. It is a schematic block diagram which shows the biogas and pyrolysis gas production | generation system which concerns on one embodiment of this invention.

Explanation of symbols

1 Biogas, 2 Fermentation liquid, 3 Fermenter, 4 Biogas line,
5A 1st biodesulfurization device, 5B 2nd biodesulfurization device,
7 partly removed fermentation broth, 8A, 8B heating device, 9 high temperature fermentation broth,
11A, 11B Circulating fluid tank, 13A, 13B Sprinkling part, 14 Supporting part,
15 sulfur-oxidizing bacteria, 17A first condensing device, 17B second condensing device,
18 slurry tank, 31 pyrolysis gas, 32 pyrolysis residue,
33 Pyrolysis furnace 34 Pyrolysis gas line 42 Fermentation liquid 42 Fermenter

Claims (6)

A fermenter that ferments organic waste to produce biogas;
A first biodesulfurization device that sends the biogas from the fermenter and performs biodesulfurization treatment on the biogas;
A first temperature control for heating the fermentation liquor partially taken out from the fermenter and sending it to the first biological desulfurization apparatus to bring the temperature of the first biological desulfurization apparatus to a temperature of 50 ° C to 90 ° C. Means,
And a first condensing device that cools the biogas sent from the first biodesulfurization device and collects the condensate after the first biodesulfurization device. system. A pyrolysis furnace that generates pyrolysis gas by heating the waste to be pyrolyzed;
A second biological desulfurization apparatus that sends the pyrolysis gas from the pyrolysis furnace and performs biodesulfurization treatment on the pyrolysis gas;
A portion of the fermented liquor taken out from the fermenter for fermenting organic waste is heated and sent into the second biological desulfurization apparatus, whereby the second biological desulfurization apparatus is heated to a temperature of 50C to 90C. Second temperature control means for
And a second condensing device for cooling the pyrolysis gas sent from the second biodesulfurization device and recovering the condensate after the second biodesulfurization device. Gas generation system. A fermenter that ferments organic waste to produce biogas;
A first biodesulfurization device that sends the biogas from the fermenter and performs biodesulfurization treatment on the biogas;
A first temperature control for heating the fermentation liquor partially taken out from the fermenter and sending it to the first biological desulfurization apparatus to bring the temperature of the first biological desulfurization apparatus to a temperature of 50 ° C to 90 ° C. Means,
A biogas generation system comprising: a first condensing device that cools biogas sent from the first biodesulfurization device after the first biodesulfurization device and collects a condensate;
A pyrolysis furnace that generates pyrolysis gas by heating the waste to be pyrolyzed;
A second biological desulfurization apparatus that sends the pyrolysis gas from the pyrolysis furnace and performs biodesulfurization treatment on the pyrolysis gas;
A second temperature control for heating the fermentation liquor partially taken out from the fermenter and sending it to the second biological desulfurization apparatus to bring the second biological desulfurization apparatus to a temperature of 50C to 90C. Means,
A pyrolysis gas generation system comprising: a second condensing device that cools the pyrolysis gas sent from the second biodesulfurization device after the second biodesulfurization device and collects the condensate. A biogas and pyrolysis gas generation system comprising: A biogas production method for producing a biogas by fermenting an organic waste in a fermentor, producing a biogas by passing the biogas through a first biodesulfurization apparatus and performing a desulfurization treatment,
When biodesulfurization treatment is performed on the biogas, the fermentation liquor partially taken out from the fermenter is heated and sent into the first biodesulfurization apparatus to be treated at a temperature of 50 ° C. to 90 ° C. The biogas generation method is characterized by cooling the biogas that has undergone the biological desulfurization treatment step and collecting the condensate. A pyrolysis gas generation method for generating a pyrolysis gas by heating a waste to be pyrolyzed, generating a pyrolysis gas, passing the pyrolysis gas through a second biological desulfurization apparatus, and performing a desulfurization treatment. ,
When performing the biological desulfurization treatment on the pyrolysis gas, the fermentation liquor partially taken out from the fermenter for fermenting the organic waste is heated and sent into the second biological desulfurization apparatus, so A method for producing a pyrolysis gas, characterized in that the pyrolysis gas treated at a temperature of 90 ° C. and cooled through the biological desulfurization treatment step is recovered to recover a condensate. A biogas production method for producing a biogas by fermenting an organic waste in a fermentor, producing a biogas by passing the biogas through a first biodesulfurization apparatus and performing a desulfurization treatment,
When biodesulfurization treatment is performed on the biogas, the fermentation liquor partially taken out from the fermenter is heated and sent into the first biodesulfurization apparatus to be treated at a temperature of 50 ° C. to 90 ° C. And a biogas generation process for recovering the condensate by cooling the biogas that has undergone the biodesulfurization process,
A pyrolysis gas generation method for generating a pyrolysis gas by heating a waste to be pyrolyzed, generating a pyrolysis gas, passing the pyrolysis gas through a second biological desulfurization apparatus, and performing a desulfurization treatment. ,
In carrying out the biological desulfurization treatment on the pyrolysis gas, the fermentation liquor partially taken out from the fermenter is heated and sent into the second biological desulfurization apparatus at a temperature of 50 ° C. to 90 ° C. And a pyrolysis gas generation step characterized by cooling the pyrolysis gas that has undergone the biological desulfurization treatment step and recovering the condensate, and a biogas and pyrolysis gas generation method.

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