JPH0441591B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a reaction method and a reaction apparatus for reacting a reacted liquid such as an acetic acid fermentation liquid using aerobic microorganisms such as acetic acid bacteria. (Prior Art) In recent years, research has been actively conducted on methods of reacting reaction liquids using microorganisms, and as an example, a method using immobilized acetic acid bacteria has been developed and is attracting attention. In the research report below, acetic acid bacteria, which are aerobic microorganisms, are immobilized on a ceramic honeycomb structure, and a fermentation stock solution is supplied with ventilation into a reaction tower containing this honeycomb structure, and the same stock solution is continuously fed. A method for producing table vinegar by fermentation has been reported. "Research on vinegar production technology using immobilized acetic acid bacteria" (Aichi Prefectural Food Industry Research Institute, 1985 Research Results Dissemination Seminar, March 25, 1986, Kondo et al.). According to this method, since acetic acid bacteria are immobilized, continuous fermentation is possible by continuously supplying a fermentation stock solution, and acetic acid fermentation can be performed more efficiently than conventional methods that do not use immobilized acetic acid bacteria. I can do it. (Problems to be Solved by the Invention) The present invention provides a reaction method and a reaction apparatus using a honeycomb structure in which aerobic microorganisms are not immobilized, including acetic acid fermentation, in which a liquid to be reacted and a gas containing oxygen are The purpose is to further increase reaction efficiency by controlling the amount of supply of . (Means for Solving the Problems) The present invention relates to a reaction method and a reaction device using microorganisms immobilized on ceramics. A reactant liquid and a gas containing oxygen at a predetermined concentration are supplied to a reaction tower containing a ceramic honeycomb structure, and the reactant liquid is passed through the honeycomb structure in the form of a foam to cause a reaction by the microorganisms. In addition, by controlling the supply amounts of the reactant liquid and gas, the foam state of the reactant liquid is maintained from the lower end to the upper end of the honeycomb structure. Therefore, in this first invention, when the supply amount of the reactant liquid is Lml/min and the supply amount of the gas is Gml/min, these supply amounts are L/min.
It is preferable to control to the relationship G=a×10 ⁻⁴ (0.7≦a≦7). Moreover, the reaction device which is the second invention of the present invention is
The bottomed cylinder has a gas supply hole for supplying a gas containing oxygen at a predetermined concentration in the lower part, and a reactant liquid supply hole for supplying the reacted liquid above the gas supply hole, and also has a reaction liquid in the upper part of the cylinder. a reaction tower having a reaction liquid discharge hole for discharging; a porous ceramic honeycomb structure disposed between a reactant liquid supply hole and a reaction liquid discharge hole in the reaction tower and immobilizing aerobic microorganisms; The reactor is characterized by comprising a perforated plate disposed between the reactant liquid supply hole and the gas supply hole in the column, which disperses the supplied gas and makes the supplied reactant liquid foam-like. Therefore, it is preferable that the reaction apparatus of the second invention includes one or more reaction towers connected in series, and the reaction tower is equipped with the above-mentioned gas circulation means. The honeycomb structure of the present invention may be made of any type of ceramic, as long as it has corrosion resistance against the reacted liquid and reaction products, and has no practical problems in terms of mechanical strength, heat resistance, and thermal shock resistance, such as mullite. , cordierite, silica, alumina, zirconia, titania, and the like are used as appropriate. In addition, the honeycomb structure of the present invention must be porous in order to immobilize aerobic microorganisms, and the porosity of all pores is 20%.
In the above, the average pore diameter is preferably up to about 30 times larger than the microorganism to be immobilized, and preferably in the range of 5 to 100 μm. Furthermore, in the honeycomb structure of the present invention, since the foamy reaction liquid is passed through a large number of through holes extending in the longitudinal direction, the hydraulic diameter of the through holes is 1 to 10 mm.
It is preferable that it is in the range of . The microorganisms used in the present invention are aerobic microorganisms such as acetic acid bacteria, and such microorganism cells are cultured at high concentration and physically adsorbed to the honeycomb structure, and then an appropriate amount of reactant liquid is added and cultured for several days. It is fixed by this. The reacted liquid used in the present invention is, for example, a raw material liquid for acetic acid fermentation, and includes alcohol-containing brewed products obtained by saccharifying starch-containing raw materials and alcohol fermentation, sake, grape wine, persimmon wine, and mixtures thereof. . (Actions and Effects of the Invention) According to the reaction method of the present invention, a sufficient amount of oxygen can be supplied to the aerobic microorganisms immobilized on the honeycomb structure together with the reacted liquid, and thereby the aerobic microorganisms Continuous reactions can be carried out efficiently. Further, according to the reaction apparatus of the present invention, the gas supplied into the reaction tower becomes minute bubbles and is guided into the reaction liquid by the porous plate, so that the reaction liquid becomes bubble-like containing gas. This foamy reactant liquid is maintained while passing through the honeycomb structure, supplies oxygen to the aerobic microorganisms immobilized on the honeycomb structure, and undergoes an efficient reaction by the action of the microorganisms. (Example) (1) Reaction Apparatus () The reaction apparatus 10 shown in FIG. 1 is an acetic acid fermentation apparatus according to the first example of the present invention, and the reaction apparatus 10 is equipped with a reaction column 11 and a reaction liquid tank 12. , a honeycomb structure 13 and a perforated plate 14 are provided in the reaction tower 11.
is located. The reaction tower 11 has a cylindrical shape with both upper and lower ends closed, and has a gas supply hole 11a at the bottom and a substrate liquid supply hole for supplying the reacted liquid (hereinafter referred to as substrate liquid) at the lower side thereof. 11b
and a reaction liquid discharge hole 11 on the upper side thereof.
It has c. The honeycomb structure 13 has a substrate liquid supply hole 11b and a reaction liquid discharge hole 1 in the reaction tower 11.
1c, and the porous plate 14 is arranged within the reaction tower 11 between the gas supply hole 11a and the substrate liquid supply hole 11b. In the reaction tower 11, the gas supply hole 11a is connected to a gas supply line 15a equipped with a gas supply pump, and the substrate liquid supply hole 11b is connected to a substrate liquid supply line 15b equipped with a liquid supply pump. , and the reaction liquid discharge hole 11c is connected to the reaction liquid discharge pipe 15c. The other end of this reaction liquid discharge pipe 15c is connected to the inflow hole 12a of the reaction liquid tank 12. The honeycomb structure 13 is made of mullite porous ceramics and has an average pore diameter of 10 μm.
It has countless pores, and the porosity of all the pores is 40%. The honeycomb structure 13 has a large number of through holes extending in its longitudinal direction, each through hole having a hydraulic diameter of 3 mm, and acetic acid bacteria are immobilized therein. The porous plate 14 is made of porous ceramics similar to the honeycomb structure 13, and has an average pore diameter of 10μ.
It has a porosity of 40% and has countless pores of m. In the reactor 10, a raw material liquid for acetic acid fermentation, which is a substrate liquid, is continuously supplied into the reaction tower 11 through the supply pipe 15b, and at the same time, air is supplied as it is or with the oxygen content adjusted, and is supplied to the supply pipe 15a. It is continuously supplied into the reaction column 11 through the reactor. In the reaction tower 11, the supplied air becomes numerous microscopic bubbles by the action of the porous plate 14 and is introduced into the substrate liquid, and the substrate liquid becomes bubbles containing air and flows through each hole in the honeycomb structure 13. Pass upward through the hole. During this time, oxygen is supplied to the acetic acid bacteria immobilized on the structure 13, the substrate liquid is continuously fermented with acetic acid, and the fermentation reaction liquid is guided into the reaction liquid tank 12 through the discharge pipe 15c together with air. (2) Reaction Apparatus () The reaction apparatus 20 shown in FIG. 2 is an acetic acid fermentation apparatus according to the second embodiment of the present invention, and the reaction apparatus 20 has a reaction column 21, similar to the reaction apparatus 10 of the first embodiment. Although it includes a reaction liquid tank 22, a honeycomb structure 23, and a perforated plate 24, the gas supply pipe 2
The reactor differs from the reactor 10 in that the other end of the reactor 5a is connected to the top of the reaction liquid tank 22. In the reactor 20, the supplied air is passed through the supply pipe 25a and the discharge pipe 25c to the reaction tower 21.
It is a closed system that circulates between the reaction liquid tank 22 and the reaction liquid tank 22, and the amount of air discharged can be reduced to zero or an extremely small amount. To control the amount of oxygen, an oxygen sensor and a solenoid valve that opens and closes in response to an electrical signal from the sensor are used. The reaction device 20
is particularly effective when the substrate liquid and reactants are volatile. (3) Reaction device () The reaction device 30 shown in FIG. 3 is an acetic acid fermentation device according to the third embodiment of the present invention, and the reaction device 30 includes an intermediate tank 36, a second reaction column 31A, and a second honeycomb structure. The other two reactors 10 and 20 are equipped with a body 33A and a second porous plate 34A.
It is different from In particular, the reaction apparatus 30 has a second reaction tower 31A and an intermediate tank 36 interposed between the reaction tower 31 and the reaction liquid tank 32, so that both reaction towers 31, 31
A is connected in series, and a discharge pipe 35c from the reaction tower 31 is connected to the top of the intermediate tank 36. Second reaction tower 3
Second gas supply pipe 37a that supplies gas to 1A
is connected to the top of the intermediate tank 36 and the bottom of the second reaction tower 31A, the second substrate liquid supply pipe 37b is connected to the lower side of the intermediate tank 36 and the second reaction tower 31A, and the second discharge pipe 37c is the second reaction tower 31
It is connected to the upper side of A and the top of the reaction liquid tank 32. The reactor 30 has two reaction towers 3
1,31A is used to carry out acetic acid fermentation in two stages, thereby increasing the reaction efficiency. (4) Acetic acid fermentation () A continuous fermentation test of acetic acid was conducted using the reaction apparatus 10 shown in FIG. The reaction column 11 in the reactor 10 has a diameter of 100 mm, a length of 380 mm, and an effective volume of 3, and the reaction column 11 has a diameter of 98 mm.
Three honeycomb structures 13 with a length of 100 mm and a length of 100 mm are housed, and a perforated plate 14 is housed below them. A bacterial strain (Acetobacter acetei IFO03284) was used to immobilize acetic acid bacteria on the honeycomb structure 13, and the alcohol concentration of the substrate solution was adjusted to 10V/
A mixture of equal amounts of sake and persimmon wine adjusted to V%
The bacterial strain was cultured in 300 ml at 30°C for 36 hours, and the culture solution was put into the reaction tower 11 containing three honeycomb structures 13, and the substrate solution was added.
700 ml was added and cultured for 3 days, whereby the acetic acid bacteria were physically adsorbed and immobilized on the ceramic members constituting each honeycomb structure 13. In the reactor 10, the inside of the reaction tower 11 is 34
℃, and air and substrate liquid were supplied into the reaction tower 11 under the conditions shown in the columns of "Aeration amount" and "Substrate liquid amount" in Table 1. Under these conditions, it took 10 days to obtain a stable amount of acetic acid produced, and after that, the amount of acetic acid produced remained stable for more than 100 days with almost no fluctuation. The results are shown in the "acetic acid production amount" and "substrate liquid state" columns in the table. In the table, the column "Spacing" indicates the distance between the lower end of the honeycomb structure 13 and the upper end of the porous plate 14 in the reaction tower 11, and the column "Substrate liquid state" indicates the foam state of the substrate liquid. were classified and displayed in the following four stages. (1) Slight foam: A slight amount of foam is observed at the top of the substrate liquid. (2) Insufficient foam: Foaming is observed only in the upper part of the substrate liquid (3) Good foam: The entire foam is foamed and the foam is almost uniform (4) Excessive foam: A portion of the substrate liquid Large bubbles with a diameter of 10 mm or more are observed in

[Table] No. 6 that obtained the best results in the above fermentation test
In the test, the acetic acid concentration of the reaction solution obtained was
It was 5.4 w/v%, and about 3 v/v% of ethyl alcohol in the substrate solution was volatilized. From the above test results, it is necessary to pass the substrate liquid through the honeycomb structure in a foamy state in the acetic acid fermentation test, and in order to maintain the substrate liquid in a foamy state while passing through the honeycomb structure, the substrate liquid must be passed through the honeycomb structure in a foamy state. It is preferable that the liquid supply amount L (ml/min) and the ventilation amount G (ml/min) have a predetermined relationship. This preferable relationship is as follows with reference to Table 1. L/G=a×10 ⁻⁴ (1≦a≦2) In addition, preferable values of a in other substrate liquids are as shown in Table 2. Therefore, the value of a is
It is preferable that the range is 0.7≦a≦7.

[Table] (5) Acetic acid fermentation () Continuous acetic acid fermentation tests were conducted using the reaction apparatus 30 shown in Fig. 3; tests were conducted using an open system in which supplied air was discharged from the reaction liquid tank 32 without circulation; A separate test was conducted using a closed system in which the air supplied after a period of time was circulated and an amount of oxygen corresponding to the amount of oxygen consumed was supplied to the circulating air. In each test, both reaction towers 31, 31A, honeycomb structures 33, 33A, and perforated plates 33, 3
4A is the same as the reaction column 11, honeycomb structure 13, and perforated plate 14 in the reaction apparatus 10, and the fermentation conditions were conducted under the same conditions as Test No. 6 for acetic acid fermentation () in the open system test, and In a closed system test, the reaction liquid tank 32
The gas discharge rate was 75 ml/min. The acetic acid concentration in the resulting reaction solution was 6.0W/V% in the open system test and 6.0W/V% in the closed system test.
7.3 W/V%, and the fermentation efficiency is significantly improved compared to the case where the reaction tower consists of only one tower.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the first embodiment of the reaction apparatus according to the present invention, FIG. 2 is a schematic diagram showing the second embodiment, and FIG. 3 is a schematic diagram showing the third embodiment of the reactor. It is. Explanation of symbols, 10, 20, 30... Reactor,
11,21,31,31A...Reaction tower, 12,2
2, 32... Reaction liquid tank, 13, 23, 33, 33
A...honeycomb structure, 14, 24, 34, 34
A...Perforated plate.

Claims (1)

[Scope of Claims] 1. A reactant liquid and a gas containing oxygen at a predetermined concentration are supplied to a reaction tower containing a porous ceramic honeycomb structure in which aerobic microorganisms are immobilized, and the reactant liquid is bubbled. The reaction liquid is caused to react by the microorganisms by passing through the honeycomb structure, and the foam state of the reaction liquid is changed from the lower end to the upper end of the honeycomb structure by controlling the supply amount of the reactant liquid and gas. A reaction method using microorganisms immobilized on ceramics, which is characterized by being maintained until the end of the process. 2 When the supply amount of the reacted liquid is Lml/min and the supply amount of the gas is Gml/min, the relationship between these is L/G=a×10 ^-4 (however, 0.7≦a≦7). The reaction method according to claim 1, wherein the reaction method is controlled. 3 The bottomed cylinder has a gas supply hole for supplying a gas containing oxygen at a predetermined concentration in the lower part and a reaction liquid supply hole for supplying the reaction liquid above the gas supply hole, and a reaction liquid is provided in the upper part of the cylinder. a reaction tower having a reaction liquid discharge hole for discharging the reaction liquid; a porous ceramic honeycomb structure in which aerobic microorganisms are immobilized and arranged between the reaction liquid supply hole and the reaction liquid discharge hole in the reaction tower; A porous plate arranged between a reactant liquid supply hole and a gas supply hole in the reaction tower to disperse the supplied gas and fix the supplied reactant liquid in the form of a bubble in a ceramic. A reaction device using microorganisms. 4. The reaction apparatus according to claim 3, comprising one or more reaction towers connected in series. 5. The reaction apparatus according to claim 3 or 4, wherein the reaction tower is equipped with a means for circulating the gas.