JP2017123791A - Fermentation apparatus and method - Google Patents

Abstract

In a fermentation apparatus, a required amount of a neutralizing agent is reduced, and as a result, accumulation of the neutralizing agent in the system is suppressed or prevented. Valuable organic matter is fermented and produced by microorganisms in a culture solution 91 of a main fermenter 11. In the extraction means 20, valuable organic substances are extracted from the culture solution 91. In the decomposing means 40, residual organic substances in the liquid after the extraction are fermented and decomposed by microorganisms. The pH of the culture solution 91 in the main fermenter 11 is measured by the measuring means 55. A part of the liquid is sent from the extraction means 20 to the decomposition means 40 from one or more places to the main fermenter 11 by the liquid sending means 51. Based on the measured pH value, the controller 59 controls the flow rate of the liquid. [Selection] Figure 1

Description

  The present invention relates to a fermentation apparatus and a fermentation method, and more particularly to an apparatus and a method for performing fermentation treatment such as fermentation production and fermentation decomposition of organic matter by microorganisms in a liquid.

  Patent Document 1 discloses a system for extracting ethanol and the like from biomass by fermentation. The remaining liquid after taking out is drained and recycled, and the water is used as a pre-solution for ethanol fermentation. When the pH is out of the range, it is described that the pH is adjusted with an acid or alkali neutralizing agent.

JP 2004-121055 A

In the above-mentioned patent documents, a neutralizing agent is added as necessary. However, the neutralizing agent that has been added cannot often be removed by this treatment, and the neutralizing agent accumulates in the system and may adversely affect culture and other factors. There is.
In view of the above circumstances, an object of the present invention is to reduce or reduce the required amount of a neutralizing agent in a fermentation apparatus, and thus suppress or prevent the neutralizing agent from accumulating in the system.

In order to solve the above problems, the apparatus of the present invention is a fermentation apparatus for fermenting organic matter with microorganisms in a liquid.
Production means comprising at least one main fermenter for fermenting and producing valuable organic matter by microorganisms in the culture solution;
Extraction means for extracting the valuable organic matter from the culture solution taken out from the production means;
Decomposition means for fermenting and decomposing residual organic substances in the liquid after extraction by microorganisms;
Measuring means for measuring the pH of the culture solution in the main fermentor;
A liquid sending means for sending a part of the liquid from one or a plurality of locations from the extraction means to the outlet of the decomposition means, to the main fermenter;
And a control means for controlling the flow rate of the liquid delivery means based on the measured value of the pH.
The method of the present invention is a fermentation method in which organic matter is fermented by microorganisms in a liquid.
A production process in which valuable organic matter is fermented and produced by microorganisms in the culture solution;
An extraction step of extracting the valuable organic matter from the culture solution after the generation step;
A decomposition step in which residual organic substances in the liquid after the extraction step are fermentatively decomposed by microorganisms;
A measuring step of measuring the pH of the culture solution in the generating step;
A liquid-feeding step of sending a part of the liquid at one or a plurality of points in time from the extraction step to after the decomposition step;
And a control step of controlling a liquid supply flow rate of the liquid supply step based on the measured value of the pH.

  Usually, the pH of the solution after extraction and the solution during or after decomposition is different from the pH of the culture solution in the generation means (generation step). The pH of the culture solution can be adjusted by mixing these different pH solutions into the culture solution instead of the neutralizing agent. As a result, the amount of neutralizing agent added can be reduced, or the neutralizing agent addition can be made unnecessary. Therefore, accumulation of the neutralizing agent in the system can be suppressed or prevented. In addition, the recycle rate of the culture solution can be increased, and the supply flow rate of the culture solution can be reduced.

It is preferable that the liquid feeding means is connected to one or a plurality of locations among an outlet portion of the extracting means and an inlet portion, a midway portion, and an outlet portion of the decomposition means.
Sending a part of the liquid at one or a plurality of times after the extraction step and before the decomposition step and during and after the decomposition step to the generation step while controlling the flow rate based on the measured value of the pH. preferable.
Thus, the pH of the culture solution can be adjusted to a desired value.

It is preferable that the decomposition means includes an acid fermenter connected to the extraction means and a methane fermenter provided on the downstream side of the acid fermenter. It is preferable that the said liquid feeding means is connected to at least one place among the said acid fermenter and the said methane fermenter, and the exit part of the said methane fermenter.
It is preferable that the decomposition step includes an acid fermentation step in which the liquid after the extraction step is subjected to acid fermentation, and a methane fermentation step in which the liquid after the acid fermentation step is subjected to methane fermentation. A part of the liquid at one or both of the time after the acid fermentation process and before the methane fermentation process and after the methane fermentation process is sent to the generation process while controlling the flow rate based on the measured value of the pH. It is preferable.
Thereby, the pH of the culture solution can be adjusted to ensure a desired value.

The decomposition means includes a reflux path, the upstream end of the reflux path is connected to the outlet of the methane fermentation tank, and the downstream end of the reflux path is connected to the inlet of the acid fermentation tank Is preferred.
It is preferable that the culture method further includes a refluxing step of mixing another part of the liquid after the methane fermentation with the liquid before the acid fermentation.
The liquid after methane fermentation has a higher pH than the liquid before acid fermentation. By returning this high pH liquid to the acid fermenter, it is possible to prevent the pH of the acid fermenter (liquid during the acid fermentation process) from becoming lower than necessary. Thereby, even if it does not add a neutralizing agent separately to an acid fermentation tank (liquid in an acid fermentation process), favorable acid fermentation can be performed. Since a separate neutralizing agent is unnecessary, it does not accumulate.

The fermentation method further comprises a supply step of supplying the stock solution of the culture solution to the main fermenter,
In the control step, it is preferable to control the liquid feed flow rate and the stock solution supply flow rate based on the measured value of the pH.
Thereby, not only can the pH of the culture solution in the main fermentation tank (generation process) be controlled as desired, but also the liquid supply flow rate to the main fermentation tank (generation process) can be kept constant. As a result, the flow rate of the liquid flowing through the liquid flow path of the system can be kept constant.

An addition step in which the fermentation method adds a neutralizing agent to the culture solution in the production step; a separation and discharge step in which solids are separated and discharged from the solution after the extraction step and before the decomposition step;
Further comprising
The decomposition step includes an anaerobic treatment step, and an aerobic treatment step after the anaerobic treatment step,
The amount of the neutralizing agent added is equal to the sum of the amount of the neutralizing agent in the discharge discharged in the separation discharge step and the amount of the neutralizing agent in the liquid entering the aerobic treatment step. It is preferable to make it.
This can more reliably prevent the neutralizing agent from accumulating in the system. Even if ammonia derived from the neutralizing agent is contained in the liquid entering the aerobic treatment step, it can be decomposed by the aerobic treatment.

  According to the present invention, the required amount of neutralizing agent can be reduced. As a result, accumulation of the neutralizing agent in the system can be suppressed or prevented.

FIG. 1 is a circuit diagram showing a schematic configuration of a fermentation apparatus according to the first embodiment of the present invention. FIG. 2 is a circuit diagram showing a schematic configuration of a fermentation apparatus according to the second embodiment of the present invention. FIG. 3 is a circuit diagram showing a schematic configuration of a fermentation apparatus according to the third embodiment of the present invention. FIG. 4 is a circuit diagram showing a schematic configuration of a fermentation apparatus according to the fourth embodiment of the present invention. FIG. 5 is a circuit diagram showing a schematic configuration of a fermentation apparatus according to the fifth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 shows a fermentation apparatus 1 according to the first embodiment of the present invention. The fermentation apparatus 1 includes a stock solution supply unit 2, a generation unit 10, an extraction unit 20, a solid-liquid separation unit 30, a decomposition unit 40, and a liquid channel 9 that connects them. Along the flow direction of the liquid flow path 9, the stock solution supply means 2, the generation means 10, the extraction means 20, the solid-liquid separation means 30, and the decomposition means 40 are arranged in this order. The liquid flow path 9 includes liquid paths 9a, 9b, 9c, 9d between two adjacent means 2, 10, 20, 30, 40, and liquid paths 9e, 9f, 9g on the inside and downstream of the decomposition means 40. Including.
Although illustration is omitted, a liquid feed pump is provided in each of the liquid passages 9a to 9g.

In the stock solution supply means 2, a culture stock solution 90 is stored. Most of the culture stock solution 90 is water (H ₂ O). Nutrients such as vitamins and phosphoric acid are dissolved in this. The culture stock solution 90 is acidic.
The stock solution supply means 2 and the generation means 10 are connected by a stock solution supply path 9a.

  The generation means 10 includes at least one main fermenter 11. In the main fermenter 11, a culture stock solution 90 from the stock solution supply means 2 is stored as a culture solution 91. An anaerobic microorganism for main fermentation is cultured in the culture solution 91.

  Although detailed illustration is omitted, a substrate is supplied to the main fermenter 11. The substrate may be any substance that is an energy source for anaerobic microorganisms, whether organic or inorganic. The anaerobic microorganism for main fermentation ferments and produces organic substances such as ethanol and acetic acid from the substrate.

  The composition of the culture solution 91 is not the same as the composition of the culture stock solution 90 and includes components consumed by metabolism of the anaerobic microorganisms for main fermentation and components produced (such as ethanol and other fermentation products). Yes. The culture solution 91 is weaker acidic than the culture stock solution 90.

The main fermenter 11 is provided with a neutralizing agent adding means 60. The neutralizer addition means 60 includes a neutralizer source 61 and an addition path 62. The neutralizing agent source 61 stores an alkaline neutralizing agent such as sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonia (NH ₃ ) or the like. An addition path 62 from the neutralizer source 61 is connected to the main fermenter 11.

The production | generation means 10 and the extraction means 20 are connected by the culture solution delivery path 9b.
The extraction means 20 includes one or a plurality of distillation columns 21. A distillation steam path 22 from the final distillation column 21 extends to a purification apparatus (not shown). Further, an extraction residual liquid passage 9 c from the bottoms outlet 23 extends to the solid-liquid separation means 30.

The solid-liquid separation unit 30 includes a filter dehydrator 31, for example. A solid material discharge passage 34 extends from the filter dehydrator 31 to the outside of the system.
The liquid outlet of the solid-liquid separation means 30 and the decomposition means 40 are connected by a separated liquid path 9d.

  The decomposition unit 40 includes an anaerobic processing unit 41 and an aerobic processing unit 44 (post-processing unit). The anaerobic treatment unit 41 includes an acid fermentation tank 42 and a methane fermentation tank 43. The downstream end of the separated liquid passage 9 d is connected to the acid fermentation tank 42. In the acid fermentation tank 42 (subfermentation tank), a liquid 93 (acid fermentation target liquid) after solid separation is stored. In the acid fermentation target liquid 93 in the acid fermentation tank 42, acid fermentation bacteria are cultured.

  A methane fermentation tank 43 is connected to the downstream side of the acid fermentation tank 42 in the decomposition means 40 via an acid-fermented liquid passage 9e. In the methane fermentation tank 43 (subfermentation tank), a liquid 94 (liquid for methane fermentation) after acid fermentation treatment is stored. In the liquid 94 in the methane fermentation tank 43, methane fermentation bacteria are cultured.

  An aerobic treatment unit 44 is provided on the downstream side of the methane fermentation tank 43 in the decomposition means 40. The methane fermentation tank 43 and the aerobic processing part 44 are connected by a methane-fermented liquid passage 9f.

  The pH in the liquid flow path 9 is lowest in the culture stock solution 90, and increases in the order of the culture solution 91, the extraction residual solution 92, the solution 94 after the acid fermentation treatment, and the solution 95 after the methane fermentation treatment.

  The fermentation apparatus 1 further includes pH adjusting means 50. The pH adjusting means 50 includes a liquid feeding means 51, a pH measuring device 55 (pH measuring means), and a controller 59 (control means). The liquid feeding means 51 has a liquid feeding path 52 and a liquid feeding pump 53. The upstream end of the liquid feeding path 52 is connected to the methane-fermented liquid path 9f (the middle part of the decomposition means 40). That is, the liquid feeding means 51 is connected to one place from the extraction means 20 to the outlet portion of the decomposition means 40. A part 95 b of the liquid 95 after the methane fermentation treatment can be diverted to the liquid feeding path 52. A liquid feed pump 53 is provided in the middle of the liquid feed path 52. The downstream end of the liquid feeding path 52 is connected to the stock solution supply path 9 a and is thus connected to the main fermentation tank 11.

  A pH measuring device 55 is connected to the main fermenter 11. The pH value of the culture solution 91 is measured by the pH measuring device 55. An output signal line of the pH measuring device 55 is connected to the controller 59. A control signal line of the controller 59 is connected to the liquid feed pump 53. The controller 59 includes a microcomputer and a drive circuit for the liquid feed pump 53.

The fermenter 1 operates as follows.
<Supply process>
The culture stock solution 90 is supplied from the stock solution supply means 2 to the main fermenter 11. This stock solution 90 is added to the culture solution 91 in the main fermentation tank 11.

<Generation process (culture process)>
In the culture solution 91 of the main fermenter 11, the anaerobic microorganisms for main fermentation are cultured. The anaerobic microorganisms for main fermentation ferment and produce valuable organic substances such as ethanol (C ₂ H ₅ OH). As a by-product, acidic organic compounds such as acetic acid are also produced. Therefore, the pH of the culture solution 91 tends to be low.

<Addition process>
An appropriate amount of neutralizing agent is added to the culture solution 91 from the neutralizing agent adding means 60. Thereby, it can prevent that the pH of the culture solution 91 falls more than needed, and can promote the fermentation activity of the anaerobic microorganisms for main fermentation.

A part of the culture solution 91 in the main fermenter 11 is taken out to the culture solution delivery path 9 b and sent to the distillation column 21.
<Extraction process>
In the distillation column 21, ethanol (valuable organic matter) is extracted by distilling the culture solution 91. The extracted ethanol is taken out from the distilling steam path 22 and further purified for use in various ways.

  The residual liquid 92 after the extraction contains biomass such as the anaerobic microorganisms for main fermentation and other residual organic substances (COD (Chemical Oxygen Demand) components). The post-extraction residual liquid 92 is sent to the filter dehydrator 31 through the extraction residual liquid path 9c.

<Separate discharge process>
In the filter dehydrator 31, the extraction residual liquid 92 is compressed and solid-liquid separated. The solid matter is in a dehydrated cake state and is discharged out of the system from the solid matter discharge path 34. Part of the neutralizing agent is mixed in the discharge containing solid matter.
The liquid 93 after solid matter separation is sent to the decomposition means 40 through the separated liquid passage 9d.

<Disassembly process>
In the decomposition means 40, an anaerobic processing step is performed in the anaerobic processing unit 41, and then an aerobic processing step is performed in the aerobic processing unit 44. As an anaerobic treatment process, an acid fermentation process is first performed in the acid fermentation tank 42, and then a methane fermentation process is performed in the methane fermentation tank 43.

<Anaerobic treatment process-acid fermentation process>
In the acid fermenter 42, the residual organic matter in the liquid 93 is decomposed by acid fermentation of acid fermenting bacteria. At this time, since acid is generated, the pH of the acid fermentation tank 42 is lower than that of the methane fermentation tank 43.
The liquid 94 after the acid fermentation treatment is sent to the methane fermentation tank 43 through the acid-fermented liquid channel 9e.

<Anaerobic treatment process-methane fermentation process>
In the methane fermentation tank 43, residual organic substances in the liquid 94 are decomposed by methane fermentation of methane fermentation bacteria. At this time, since carbon dioxide and methane are produced, the pH of the methane fermentation tank 43 is relatively high.
COD can be reduced by acid fermentation treatment and methane fermentation treatment. Of the liquid 95 after the methane fermentation treatment, the liquid 95a excluding the reflux liquid 95b described later is sent to the aerobic treatment section 44 through the methane fermentation completed liquid passage 9f.

<Aerobic treatment process>
The aerobic treatment unit 44 aerobically decomposes the organic matter in the liquid 95a with aerobic microorganisms. This can reduce the COD to the environmental release standard. Even if the liquid 95a contains ammonia derived from the neutralizing agent from the neutralizing agent adding means 60, it can be decomposed by the aerobic treatment.
<Liquid release process>
The waste liquid 96 after the aerobic treatment is discharged out of the system as sewage through the waste liquid passage 9g. A part of the neutralizing agent is mixed in the waste liquid 96. Thereby, it is possible to prevent the neutralizing agent from accumulating in the system of the fermentation apparatus 1 in combination with the neutralizing agent discharge and the decomposition by the aerobic treatment in the separation and discharge step.

<Addition amount setting process>
Preferably, the sum of the flow rate Q ₃₄ of the neutralizing agent in the discharge from the solid discharge passage 34 and the flow rate Q _95a of the neutralizing agent in the liquid 95a entering the aerobic treatment unit 44 is the addition of the neutralizing agent. The neutralizing agent addition flow rate Q _{60 of the} means 60 is set to be substantially equal.
Q ₃₄ + Q _95a ≒ Q ₆₀ (Formula 1)
Thereby, the amount of the neutralizing agent in the fermentation apparatus 1 can be maintained in equilibrium. Further, the addition flow rate Q ₆₀ can be kept constant, and there is no need to feed back the pH value of the main fermenter 11 to the neutralizing agent addition means 60.

Further, the pH of the main fermenter 11 is adjusted by the pH adjusting means 50.
<Measurement process>
Specifically, the pH of the main fermenter 11 is measured by the pH measuring device 55. The measurement result is input to the controller 59.
<Control process>
The controller 59 controls the output of the liquid feed pump 53 based on the pH measurement value of the pH measuring device 55.
<Liquid feeding process>
By driving the liquid feeding pump 53, a part of the liquid 95 after the methane fermentation treatment (the reflux liquid 95 b) is diverted to the liquid feeding path 52. Further, the flow rate of the reflux liquid 95 b is controlled by adjusting the output of the liquid feed pump 53. The reflux liquid 95 b merges with the culture stock solution 90 from the stock solution supply means 2 in the stock solution supply path 9 a and is supplied to the main fermenter 11 together with the culture stock solution 90.

Here, the pH of the reflux liquid 95b is higher than the pH of the culture liquid 91 in the main fermenter 11. Moreover, the pH of the culture stock solution 90 is lower than the pH of the reflux solution 95b, and further lower than the pH of the culture solution 91. Therefore, the pH of the culture solution 91 can be adjusted to a desired value by increasing or decreasing the flow rate of the reflux solution 95b. That is, the pH of the main fermentation tank 11 can be adjusted using the liquid in the liquid flow path 9 subsequent to the main fermentation tank 11. Thereby, the fermentation production of ethanol by the fermentable microorganisms in the culture solution 91 can be performed satisfactorily and stably.
In addition, since the reflux liquid 95b substitutes for the neutralizing agent, the supply flow rate Q ₆₀ of the neutralizing agent from the neutralizing agent adding means 60 can be made sufficiently small. Therefore, accumulation of the neutralizing agent in the fermentation apparatus 1 can be suppressed or prevented more reliably.
Furthermore, the recycling rate of the culture solution 91 can be increased by returning the solution 95b to the main fermenter 11. Therefore, the supply flow rate of the culture stock solution 90 can be reduced.

Next, another embodiment of the present invention will be described. In the following embodiments, the same reference numerals are attached to the drawings for the same contents as those of the above-described embodiments, and the description is simplified.
[Second Embodiment]
FIG. 2 shows a second embodiment of the present invention.
In the fermenter 1B, the production | generation means 10 contains the main fermenters 11 and 11 of multiple (two in a figure). These main fermenters 11 and 11 are arranged in parallel with each other. The undiluted solution supply path 9 a is branched into a plurality and connected to each main fermenter 11. An addition path 62 is connected to each main fermentation tank 11. A culture solution delivery path 9b is drawn from each main fermenter 11. These culture solution delivery paths 9 b and 9 b merge together and are connected to the extraction means 20.

  The liquid supply path 52 of the liquid supply means 51 has a common path portion 52a and a plurality of individual path portions 52b and 52b. The common path portion 52a extends from the methane-fermented liquid path 9f. A plurality of individual path portions 52b and 52b are branched from the common path portion 52a. A liquid feed pump 53 is provided in each individual path portion 52b. The individual path portion 52b corresponds to the main fermenter 11 on a one-on-one basis. Each individual path portion 52b is connected to the corresponding main fermenter 11 via the corresponding stock solution supply path 9a.

  Each main fermentation tank 11 is provided with a pH measuring device 55. The output signal lines of these pH measuring devices 55 are connected to one controller 59. A plurality of control signal lines of the controller 59 are connected to the liquid feed pumps 53 of the corresponding individual path portions 52b.

  According to the fermenter 1B, the pH of the culture solution 91 is measured for each main fermenter 11, and the output of the corresponding liquid feed pump 53 is operated according to the measured value. As a result, the flow rate of the reflux liquid 95b in the corresponding individual path portion 52b is adjusted. Thereby, the pH of each main fermenter 11 can be controlled to a desired value.

[Third Embodiment]
FIG. 3 shows a third embodiment of the present invention.
In the fermentation apparatus 1C, the control signal line of the controller 59 is connected not only to the liquid feeding pump 53 but also to the raw liquid supply pump 2P of the raw liquid supply path 9a. (Although in other embodiments (FIGS. 1-2, 4-5), the stock solution supply pump 2P exists, the illustration thereof is omitted.)

  According to the fermenter 1C, the controller 59 adjusts the output of the liquid feed pump 53 and the output of the stock solution supply pump 2P to each other. Accordingly, the flow rate of the reflux solution 95b and the flow rate of the culture stock solution 90 can be adjusted, respectively, and the flow rate ratio of these solutions 95b and 90 can be adjusted to each other, and thus the pH after mixing can be adjusted. As a result, the pH of the main fermenter 11 can be controlled more reliably as desired. Moreover, the liquid supply flow rate to the main fermentation tank 11 can be kept constant by maintaining the total flow rate of the liquids 95b and 90 constant. As a result, the liquid flow rate flowing through the liquid flow path 9 (3b to 3f) can be kept constant.

[Fourth Embodiment]
As shown in FIG. 4, the upstream end of the liquid feeding means 51 may be connected not only to one place of the liquid flow path 9 (9c to 9f) from the extracting means 20 to the separating means 40 but also to a plurality of places. . A part of the liquids 92 to 95 at a plurality of points in time from the extraction process to the decomposition process may be returned to the main fermenter 11.

  In the fermentation apparatus 1D of the fourth embodiment shown in FIG. 4, the liquid feeding means 51 includes two (plural) liquid feeding paths 52d and 52f. The liquid feeding path 52d is branched from the separated liquid path 9d. That is, the upstream end of the liquid feeding path 52d is connected between the solid-liquid separation means 30 and the decomposition means 40 (or the inlet of the decomposition means 40). Similarly to the liquid supply path 52 of the first embodiment, the liquid supply path 52f is branched from the methane-fermented liquid path 9f so as to be connected to the outlet of the methane fermentation tank 43 (the middle part of the decomposition means 40). Yes.

  A liquid feed pump 53 is provided in each liquid feed path 52d, 52f. A control signal line of the controller 59 is connected to each liquid feed pump 53. The controller 59 controls the output of the two (plural) liquid feed pumps 53.

  The liquid feeding paths 52d and 52f merge with each other on the downstream side of the liquid feeding pump 53 to form a common path 52c. The common path 52c is connected to the stock solution supply path 9a and thus connected to the main fermentation tank 11.

  According to the fermentation apparatus 1D, a part of the liquid 93 (the reflux liquid 93b) after the solid-liquid separation (after the extraction process and before the decomposition process) is diverted to the liquid feeding path 52d, and one part of the liquid 95 after the methane fermentation treatment Part (refluxing liquid 95b) can be diverted to the liquid feeding path 52f. The pH of the reflux liquid 95b is higher than the pH of the reflux liquid 93b. Furthermore, the controller 59 adjusts the output of the liquid feeding pump 53 of each liquid feeding path 52d, 52f based on the pH measured value of the main fermenter 11 by the pH measuring device 55. Accordingly, the flow rates of the reflux liquids 93b and 95b can be adjusted, respectively, and the flow rate ratio of the reflux liquids 93b and 95b can be adjusted to each other, and thus the pH after mixing can be adjusted. The reflux liquids 93b and 95b merge with each other in the common path 52c, and further merge with the culture undiluted liquid 90 in the stock solution supply path 9a and are introduced into the main fermenter 11. Thereby, the pH of the main fermenter 11 can be controlled to a desired value.

[Fifth Embodiment]
FIG. 5 shows a fifth embodiment of the present invention.
In the fermentation apparatus 1E, the liquid feeding means 51 includes two (plural) liquid feeding paths 52e and 52f. The liquid feeding path 52e is branched from the acid-fermented liquid path 9e. The upstream end of the liquid feeding path 52e is connected between the acid fermentation tank 42 and the methane fermentation tank 43 (or the outlet of the acid fermentation tank 42). Similarly to the liquid supply path 52 of the first embodiment, the liquid supply path 52f is branched from the methane-fermented liquid path 9f and connected to the outlet of the methane fermentation tank 43.

  A liquid feed pump 53 is provided in each liquid feed path 52e, 52f. A control signal line of the controller 59 is connected to each liquid feed pump 53. The controller 59 controls the output of the two (plural) liquid feed pumps 53.

  The liquid feeding paths 52e and 52f merge with each other on the downstream side of the liquid feeding pump 53 to form a common path 52c. The common path 52c is connected to the stock solution supply path 9a and thus connected to the main fermentation tank 11.

  A reflux path 45 is provided in the decomposition means 40 of the fermentation apparatus 1E. The upstream end of the reflux path 45 is connected to the methane-fermented liquid path 9 f and is connected to the outlet of the methane fermentation tank 43. The downstream end of the reflux path 45 is connected to the separated liquid path 9d, and thus connected to the inlet portion of the acid fermentation tank 42 (the inlet portion of the decomposition means 40).

  According to the fermentation apparatus 1E, a part of the liquid 94 after the acid fermentation treatment (refluxed liquid 94b) is divided into the liquid feeding path 52e, and a part of the liquid 95 after the methane fermentation treatment (refluxed liquid 95b) is fed. It can be diverted to the path 52f. The pH of the reflux liquid 95b is higher than the pH of the reflux liquid 94b. Furthermore, the controller 59 adjusts the output of the liquid feeding pump 53 of each liquid feeding path 52e, 52f based on the pH measured value of the main fermenter 11 by the pH measuring device 55. Accordingly, the flow rates of the reflux liquids 94b and 95b can be adjusted, respectively, and the flow rate ratio of the reflux liquids 94b and 95b can be adjusted to each other, and thus the pH after mixing can be adjusted. The reflux liquids 94b and 95b merge with each other in the common path 52c, and further merge with the culture undiluted liquid 90 in the stock solution supply path 9a and are introduced into the main fermenter 11. Thereby, the pH of the main fermenter 11 can be controlled to a desired value.

  Furthermore, according to the fermentation apparatus 1E, the other part (other reflux liquid 95d) of the liquid 95 after the methane fermentation treatment is diverted to the reflux path 45. This reflux liquid 95d is combined with the liquid 93 in the separated liquid path 9d through the reflux path 45 and returned to the acid fermentation tank 42. The pH of the reflux liquid 95d is higher than the pH of the acid fermentation target liquid 93. Therefore, it can suppress that the pH of the acid fermenter 42 becomes lower than necessary. As a result, good acid fermentation can be maintained without separately adding a neutralizing agent to the acid fermentation tank 42. Since a separate neutralizing agent is unnecessary, it does not accumulate.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the first embodiment (FIG. 1), the upstream end of the liquid flow path 52 only needs to be connected to a portion from the extraction means 20 to the outlet part of the decomposition means 40 in the liquid flow path 9, and the methane-fermented Not limited to the liquid path 9f, the residual extraction liquid path 9c (exit part of the extraction means 20), the separated liquid path 9d (inlet part of the separation means 40), the acid-fermented liquid path 9e (middle part of the separation means 40), Or you may be connected to the waste liquid path 9g (exit part of the separation means 40). The liquid feeding means 51 replaces a part of the liquid 95 after the methane fermentation process, a part of the liquid 92 or 93 after the extraction process and before the separation process, during the separation process or after the acid fermentation process and before the methane fermentation process. A part of the liquid 94 or a part of the liquid 96 after the separation step may be sent to the main fermenter 11. The same applies to the second and third embodiments.

In the second embodiment (FIG. 2), the number (n) of the main fermenters 11, 11 may be three or more (n ≧ 3). It is not always necessary to adjust the pH of all (n) main fermenters 11 by the pH adjusting means 50, and only a part (m, 1 ≦ m <n) of the main fermenters 11 is adjusted by the pH adjusting means 50. You may decide to do it.
In the second embodiment (FIG. 2), a controller 59 may be provided for each pH measuring device 55 and liquid feeding pump 53.
In 2nd Embodiment, the some main fermenters 11 and 11 may mutually be connected in series.

In the fourth embodiment (FIG. 4), the upstream end of the liquid feeding path 52d may be connected to the liquid paths 9c, 9e, 9f instead of the liquid path 9d, and the upstream end of the liquid feeding path 52f is Instead of the liquid path 9f, the liquid paths 9d, 9e, and 9g may be connected.
In the fifth embodiment (FIG. 5), the upstream end of the liquid feeding path 52e may be connected to the liquid paths 9c, 9d, and 9f instead of the liquid path 9e, and the upstream end of the liquid feeding path 52f is Instead of the liquid path 9f, the liquid paths 9d, 9e, and 9g may be connected.
In 4th, 5th embodiment (FIGS. 4-5), a part of the liquids 92-96 of three or more places between the extraction means 20 and the exit part of the decomposition | disassembly means 40 are sent to the main fermenter 11. Also good. That is, a part of the liquids 92 to 96 at three or more times from the extraction step to the decomposition step may be sent to the main fermenter 11.
When the extraction means 20 includes a plurality of stages of distillation towers, a part of the liquid from one stage of distillation tower to the next stage of distillation tower may be sent to the main fermenter 11.

  You may combine the original structure of several embodiment. For example, in the second embodiment (FIG. 2) and the fifth embodiment (FIG. 5) as well as the third embodiment (FIG. 3), the output of the stock solution supply pump 2P is added to the liquid feed pump 53. You may control. Also in the first to third embodiments (FIGS. 1 to 3), the decomposing means 40 may be provided with a reflux path 45 similar to that of the fifth embodiment (FIG. 5).

When the main fermenter 11 is alkaline, an acid neutralizer such as acetic acid or lactic acid may be used as a neutralizer for the neutralizer addition means 60.
As the valuable organic substance, ethanol, butanol, acetic acid or acetate, and other organic compounds may be used.

  The present invention can be applied to, for example, an ethanol production system that synthesizes ethanol from carbon monoxide generated by incineration of industrial waste.

DESCRIPTION OF SYMBOLS 1 Fermenter 1B, 1C, 1D, 1E Fermenter 2 Stock solution supply means 2P Stock solution supply pump 9 Liquid flow path 9a-9g Liquid path 10 Production means 11 Main fermenter 20 Extraction means 30 Solid-liquid separation means 34 Solid matter discharge path 40 Decomposition means 41 Anaerobic treatment section 42 Acid fermentation tank 43 Methane fermentation tank 44 Aerobic treatment section 45 Reflux path 50 pH adjusting means 51 Liquid feed means 52 Liquid feed path 53 Liquid feed pump 55 pH meter (measuring means)
59 Controller (control means)
60 Neutralizing agent addition means 52d, 52e, 52f Liquid feed path 90 Culture stock solution 91 Culture solution 92 Residual liquid after extraction (liquid after extraction process and before separation process)
93b Reflux (part of the liquid after the extraction process and before the separation process)
94b Reflux (part of the liquid in the middle of the separation process (after the acid fermentation process and before the methane fermentation process))
95d Other reflux liquid (other part of liquid after methane fermentation process)
92a Liquid 95b that enters the aerobic treatment part (aerobic treatment process) Reflux liquid (part of the liquid during the separation process (after the methane fermentation process))
96 Waste liquid (liquid at the outlet of the separation process)

Claims (10)

In a fermentation apparatus for fermenting organic matter with microorganisms in the liquid,
Production means comprising at least one main fermenter for fermenting and producing valuable organic matter by microorganisms in the culture solution;
Extraction means for extracting the valuable organic matter from the culture solution taken out from the production means;
Decomposition means for fermenting and decomposing residual organic substances in the liquid after extraction by microorganisms;
Measuring means for measuring the pH of the culture solution in the main fermentor;
A liquid sending means for sending a part of the liquid from one or a plurality of locations from the extraction means to the outlet of the decomposition means, to the main fermenter;
And a control means for controlling a liquid feed flow rate of the liquid feed means based on the measured value of the pH.   The upstream end of the liquid feeding means is connected to one or a plurality of locations among an outlet portion of the extracting means and an inlet portion, a midway portion, and an outlet portion of the disassembling means. The fermentation apparatus as described. The decomposition means includes an acid fermenter connected to the extraction means, and a methane fermenter provided on the downstream side of the acid fermenter,
The fermentation according to claim 1, wherein the liquid feeding means is connected to at least one of the acid fermenter and the methane fermenter and the outlet of the methane fermenter. apparatus.   The decomposition means includes a reflux path, the upstream end of the reflux path is connected to the outlet of the methane fermentation tank, and the downstream end of the reflux path is connected to the inlet of the acid fermentation tank The fermentation apparatus according to claim 3. In the fermentation method of fermenting organic matter with microorganisms in the liquid,
A production process in which valuable organic matter is fermented and produced by microorganisms in the culture solution;
An extraction step of extracting the valuable organic matter from the culture solution after the generation step;
A decomposition step in which residual organic substances in the liquid after the extraction step are fermentatively decomposed by microorganisms;
A measuring step of measuring the pH of the culture solution in the generating step;
A liquid-feeding step of sending a part of the liquid at one or a plurality of points in time from the extraction step to after the decomposition step;
And a control step of controlling the flow rate of the liquid feeding step based on the measured value of the pH. A supply step of supplying the stock solution of the culture solution to the main fermenter,
6. The fermentation method according to claim 5, wherein, in the control step, the liquid feeding flow rate and the supply flow rate of the stock solution are controlled based on the measured value of the pH.   Sending a part of the liquid at one or a plurality of time points after the extraction step and before the decomposition step and during and after the decomposition step to the generation step while controlling the flow rate based on the measured value of the pH. The fermentation method according to claim 5 or 6, wherein the fermentation method is characterized. The decomposition process includes an acid fermentation process for acid fermentation of the liquid after the extraction process, and a methane fermentation process for methane fermentation of the liquid after the acid fermentation process,
A part of the liquid at one or both of the time after the acid fermentation process and before the methane fermentation process and after the methane fermentation process is sent to the generation process while controlling the flow rate based on the measured value of the pH. The fermentation method according to claim 5 or 6, characterized in that.   The fermentation method according to claim 8, further comprising a refluxing step of mixing another part of the liquid after the methane fermentation process with the liquid before the acid fermentation process. An addition step of adding a neutralizing agent to the culture solution of the generation step; a separation and discharge step of separating and discharging solid matter from the liquid after the extraction step and before the decomposition step;
Further comprising
The decomposition step includes an anaerobic treatment step, and an aerobic treatment step after the anaerobic treatment step,
The amount of the neutralizing agent added is equal to the sum of the amount of the neutralizing agent in the discharge discharged in the separation discharge step and the amount of the neutralizing agent in the liquid entering the aerobic treatment step. The fermentation method according to any one of claims 5 to 9, wherein the fermentation method is performed.

Images