SU1703694A1 - Method of obtaining ethanol - Google Patents

Abstract

The invention relates to the microbiological industry, and specifically to methods for producing ethanol. The purpose of the invention is to increase the yield of the target product due to the intensification of fermentation. Wheat starch milk is hydrolyzed in 0.5% sulfuric acid at a pressure of 29.6-10-39.2-10 Pa for 0.5-1.0 hours at a temperature of 110-140 ° C, the resulting hydrolyzate is neutralized with lime to pH 4.2 and with a sugar concentration of from 16.0 to 20.9% is added to the wood hydrolyzate. The substrate is fermented at a temperature of 33-34 C for 8-10 h in the presence of pressed Saccharomyces cerevlslae yeast ras 14 at a concentration of 20 g / l. The resulting mash by known technology is subjected to distillation and rectification. 3 tab. SO with

Description

The invention relates to the microbiological industry, and specifically to methods for producing ethanol.

A known method for producing ethanol from molasses is a beet sugar production, in which yeast is used to process molasses. In the double-sided production of alcohol and baker's yeast, an improved single-stream method of fermentation of molasses is used, which yields a yield of ethyl alcohol of 66.5 dal / t of conditional starch with an anaerobic fermentation time of the wort with PB 16-17% 16-18.

The disadvantage of this method is the use of expensive raw materials, slowing down the process of fermentation of molasses by alcoholic yeast of hydrolysis production.

A method of producing ethanol from starch-containing plant material, potato starch, is known. The technology is based on the extraction of sugar from raw materials by inversion. As a result of inversion, potato starch produces glucose, which is fermented with yeast for alcohol. From the resulting brew containing up to 12% alcohol, it is extracted by the method of rectification. Starch potatoes easily inversion 1

The disadvantage of the method is that foodstuff is used as a raw material.

The closest to the invention to the technical essence is a method for producing ethanol from wood hydrolyzate. The hydrolysis of wood with diluted mineral acids includes: hydrolysis of wood. In hydrolysis apparatus by 0.5%

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sulfuric acid solution at temperatures of about 180 ° C, cooling the resulting sugar solution (hydrolyzate) by spraying, preparing the hydrolyzate for digestion by neutralizing sulfuric acid, clarifying and cooling to 40 ° C, fermenting the wort with alcohol-forming yeast, and rectification brews containing 1.0-1.5% by volume of alcohol to isolate and purify alcohol from impurities 3.

However, the method for producing ethanol from wood hydrolysates is energy-intensive, since the alcohol is recovered from the low concentration mash.

The purpose of the invention is to increase the yield of the target product due to the intensification of fermentation.

The goal is achieved by the fact that with the proposed method 1.5-2-2.0% by volume of wheat starch milk hydrolyzate with a sugar concentration of 16.0-20.9% is added to the wood hydrolyzate, followed by fermentation of the obtained substrate.

The method is carried out as follows.

The hydrolysis of wheat starch milk is carried out in a 20 dm3 hydrolysis apparatus according to the following mode: 8 dm of starch milk, 30 ml of conc. H2SCM and water to a volume of 10 dm3. The hydrolysis of wheat starch milk is carried out in 0.5% sulfuric acid at a pressure of 29.6-104-39.2 PO4 Pa for 0.5-1.0 h at 110-140 ° C. The final acidity of the solution is 0.5% Hg504.

The heating to a pressure of 29.6 × 104–39.2101 Pa is carried out for 1 h, then for 30 min – 1.0 h with the same pressure, boiling is carried out at 110–140 ° C. Unloading of the finished starch milk hydrolyzate takes 15 minutes.

The obtained hydrolyzate of starch milk after neutralization with lime to pH 4.2 is used as an additive to wood hydrolyzate in concentrations of 1.5-2.0% by volume with a sugar concentration of 16.0-20.9%. Prepared substrates are fermented with Saccharomyces c. evlsiae race 14 at a concentration of 20 g / l of compressed yeast. Fermentation is carried out in periodic and continuous conditions for 8-10 hours at 33-34 ° C. The fermented brew is subjected to distillation and rectification.

The choice of the percentage of starch milk additive to the wood hydrolyzate is due to the fact that an increase or decrease in the addition of starch milk reduces the alcohol yield.

Wheat starch milk is a byproduct of production in the production of wheat protein bread for diabetics. Crude milk is

it is white with a gray tint. A coherent suspension, without foreign smell, the mass fraction of dry substances in which not less than 15%, acidity not more than 3.5 °.

Data on the effect of hydrolysis on

sugar concentration are presented in table. 1. The maximum concentration of sugar in the solution determines the intensification of the fermentation process and. accordingly, affects the yield of the final product.

The amount of concentrated concentrated sour milk must correspond to the volume of hydrolyzed starch milk so that the final concentration in the solution after the addition of the acid corresponds to

0.5% H2SO4.

PRI me R 1. Wheat starch milk is hydrolyzed in 0.5% sulfuric acid at 39.2-U4 Pa and 140 ° C for 30 minutes, the hydrolyzate is neutralized with lime to pH

4.2, hydrolyzed wheat starch milk with a sugar concentration of 16% is added to the hydrolyzate of wood with an amount of 1.5 vol.%, Compressed Saccharomyces cerevlsiae yeast race 14 is introduced at a concentration of 20 g / l and fermented at 33 ° C for 10 h. The fermented brew is subjected to known technology for distillation and rectification.

EXAMPLE 2 Method

as in Example 1, except that the hydrolysis of wheat starch milk is carried out at 29.6-U4 Pa 110 ° C for 1 h, the wheat starch milk hydrolyzate is added with a sugar concentration of 20.9%

in the amount of 2.0 vol.%.

The data on the effect of the amount of wheat wheat starch milk hydrolyzate added on the alcohol yield are presented in Table. 2, and on the intensity of fermentation - in

tab. 3

The maximum alcohol yield was obtained by adding 1.5-2.0% by volume of wheat starch milk hydrolyzate to wood hydrolyzate and was 108.5% of the control or 55.8-55.9 liters of alcohol per 100 kg of fermented PB. An increase in the addition of wheat wheat starch milk hydrolyzate to wood hydrolyzate up to 5 vol.% Results

to a decrease in the alcohol yield by 1.3 abs.%, which is associated with incomplete fermentation of sakhar for 8-10 hours. When reducing the addition of wheat starch milk hydrolyzate to 0.5% by volume, the alcohol yield remains at the level of the control.

The proposed method allows to increase the alcohol yield.

Claims (1)

Claims of Invention A method of producing ethanol by collecting a wood hydrolyzate followed by distillation of a mash and rectification, characterized in that, in order to increase the yield of the desired product, through fermentation intensification, before fermentation, 1.5-2.0% by volume of wheat starch milk hydrolyzate with a sugar concentration of 16.0–20.9% are added to the wood hydrolyzate, and the hydration of wheat starch milk is carried out in 0.5% sulfuric acid at a pressure of 29.6 104-39.210 Pa for 0.5-1.0 h at 110-140 ° C. 2.8 l of milk + 7.6 l of water +9.8 + 0.052 conc. H-S04 24.5 29.4 8 l of milk 4 - 0.042 l of conc3H2504 19.6 29.4 49 12 liters of milk + 0.060 liters of conc. HZS04 29.4 39.2 12 liters of milk + 0.030l conc. H2S04 29.4 2,8l milk + 7,6 l of water + + 0,052 l conc. H2S0429.4 Table 1 thirty thirty thirty thirty thirty thirty thirty thirty thirty 60 15.8 17.6 20.0 16.2 18.2 14.6 18.9 19.8 10.5 16.2 Table 2 Wood hydrolyzate with PB 2.7710 Wood hydrolyzate + 4-1.5 ob.1 hydrolyzed starch milk1.0 Wood hydrolysis +  2 o6.t hydropizate starch milk1,1 Table3 7.0 7.2 . 7.25 , 51.7 1,255,8 1.2255,