JPS58129980A - Continuous preparation of alcohol by fluidizing immobilized microbial cell - Google Patents

Abstract

PURPOSE:To increase the concentration of microbial cells in the tank, in the titled process for the continuous preparation of alcohol, and to improve the productivity of alcohol, by using a fermentor furnished with a means for separating the carrier from the reaction liquid. CONSTITUTION:The fermentor 1 is composed of a fermentation tank 3 having a stirrer 2 and a carrier precipitation chamber 4 at the side of the fermentar to precipitate and collect the immobilized microbial cells and prevent the escape of the cells from the tank. As an alternative arrangement, the fermentor 11 is composed of the fermentation tank 13 and a carrier precipitation tank 14 placed separately from the fermentation tank 13, and the reaction liquid is circulated between the tank 13 and the precipitation tank 14. The immobilized microbial cell is, e.g. Zymomonas mobilis supported on pulverized vermiculite.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuous production of alcohol using an attached bacterial cell flow method.

In recent years, fermented alcohol, which can be obtained without using petrochemicals, has been in the spotlight as an energy alternative to petroleum. It is produced by fermenting sugar cane, molasses, sweet potatoes, potatoes, corn, and other cellulose or starch materials through the action of bacterial cells. In this method, alcohol productivity is thought to depend on the bacterial cell concentration. Therefore, in order to increase the bacterial cell concentration, a method of circulating the bacterial cells and a so-called immobilized cell growth method in which yeast is encapsulated in a polysaccharide-based substance are being developed. As a result, clogging or nozzle clogging occurs, and circulation of bacterial cells becomes increasingly difficult. Therefore, it is necessary to periodically clean the centrifuge, which makes the work extremely troublesome. In the latter case, there are many technical problems that are difficult to solve in mass production on an industrial scale.

In view of these circumstances, the inventors of the present invention have conducted extensive research to increase the concentration of bacterial cells in the fermenter, and as a result, have completed the present invention.

The method for producing alcohol according to the present invention uses a fermentation device equipped with a separation means for separating the carrier from the reaction solution, and the continuous production of alcohol by the adhered bacterial cell fluidization method, which is characterized by fluidizing the bacterial cells attached to the carrier. It is a manufacturing method.

Examples of fermentation devices equipped with separation means include those shown in the accompanying drawings. In other words, the fermentation apparatus (1) shown in FIG.
A carrier sedimentation section (4) is provided on the side of the tank, and the carrier is sedimented and separated in the circulation section +41 to prevent it from flowing out of the tank. In addition, the fermentation device (11) shown in Figure 1 (b) is
A carrier sedimentation tank ring is provided outside the fermentation tank t131 equipped with a stirrer [2], and the carriers flowing out from the fermentation tank (13I) are separated by sedimentation in the sedimentation tank (141), and the sedimented carriers are separated in the fermentation tank (141).
31. In addition, the fermentation device r21 shown in FIG. , the reaction liquid is allowed to flow down through the member and circulated within the tank, and the carrier is separated from the reaction liquid above the liquid circulation member.
) The fermentation device C shown in (11 is a fermentation tank can equipped with an agitator @) and these fermentation devices tll'121
11311M are all configured so that pH and temperature can be controlled to optimal values.

The carrier for adhering sprouts may be small-diameter particles with good abrasion resistance and fluidity, and the most suitable example is crushed vermiculite. The carrier is made of ceramic. Bacteria that have alcohol fermentation ability are those that have good natural adhesion,
It is not limited to the above bacteria. By fluidizing the carrier-adhered bacterial cells in the fermentation tank by stirring, the concentration of bacterial cells in the tank can be increased and the productivity of alcohol from fermentable sugar can be improved.

Example The fermentation apparatus shown in No. 1N-) was used.

First, the inside of this fermentation apparatus is cleaned with approximately 10 volumes of ethanol solution. and glucose 150 f/yeast extract
39/l KH2PO41F/J (NH4)2SO4l5le/ MgC1!2.6 H200,5V/1 antifoaming agent (manufactured by Next Summer Silicon Co., Ltd.) A culture medium consisting of 0.3 fl/1 was prepared, and this was heat-treated with crushed leeches. Stones (60 to 80 mesh) were added at 5 wL/vow, and the medium was heat sterilized. And culture solution 21 of Thymomonas mobilis ATCC Deposit No. 10988 cultured in the above carrier-containing medium! Fill the fermentation equipment and adjust the pH
The temperature was controlled at 4.5°C and 30°C, and the sterilized medium was used as a fermentation raw material at a flow rate of 0.0 using a micro pump.
Continuous fermentation was carried out by continuously supplying the mixture to a fermentation apparatus at 6 f/b.

Next, the raw material supply flow rate was increased stepwise, and the ethanol concentration at each flow rate was measured. FIG. 2 shows the relationship between the raw material dilution rate (-raw material supply flow rate/total fermentation tank actual volume #), alcohol productivity, and fermentation yield. As can be clearly seen from the figure, alcohol productivity increases as the dilution rate increases, and
At 3 hl, alcohol productivity is approximately 179/l@b.

Furthermore, the alcohol and fermentation yields were as high as 90%. On the other hand, in the basic continuous culture method that does not use carriers for bacterial attachment, the ethanol productivity is 2 to 39/l/h.
It is reported that. As described above, according to the present invention, alcohol productivity can be significantly improved.

FIG. 17 is a schematic diagram of a fermentation apparatus showing an embodiment of the present invention;
FIG. 2 is a graph showing the relationship between raw material dilution rate, alcohol productivity, and fermentation yield in Examples.

fil Cl1l f211 t311-'-・Fermentation device, t2+ [121:V 11@@Stirrer, @...
Stirring blade, f3N13B! 31 ((31"" fermenter, 14
+1111@Sedimentation section, α gradient...Sedimentation tank, ---Liquid circulation member, Foundation...Solid-liquid separation member.

that's all Patent applicant: Hitachi Zosen Corporation 4 other people , Figure 2 4 hours (h) -a-Keisenhanmine 14th grade student

Claims (1)

[Claims] 1. A method for continuous production of alcohol by an adhered bacterial cell fluidization method, characterized in that bacterial cells adhering to a carrier are fluidized using an mt4 apparatus equipped with a separation means for separating the carrier from a reaction solution.