Biomass pretreatment method

Abstract

The invention relates to a biomass pretreatment method. The action speed of microbes which can directly decompose lignin and hemicellulose is slower, and the enzyme process treatment can not effectively hydrolyze cellulose in straw; the alkaline process adopted for pulping and papermaking can form waste water pollution, the high-cost recovery is required, and the hemicellulose is also damaged; the acid process is easy to generate furan inhibiting the growth of microzyme, small molecular acid and other substances; and the steam explosion process is high in cost and complex in products and can form tar. During the biomass pretreatment process, the operation steps of firstly adopting acid and then adopting alkali are adopted; the operation conditions of high pressure and high temperature are not required; papermaking black liquor and secondary compounds inhibiting the alcoholic fermentation of the microzyme can be avoided; when the residual alkali is neutralized, excess organic acid is added, not only the residual alkali is neutralized, but also the secondary delignification through the acid process is simultaneously performed, and the added organic acid can further reduce the combination of the lignin with cellulase; and the cost is low, the steps are simple, and the operation is convenient.

Description

technical field [0001] The invention relates to a method for biomass pretreatment. Background technique [0002] Biomass pretreatment to achieve effective hydrolysis of cellulose in biomass is the key to the production of ethanol by fermentation of biomass, while the action speed of microorganisms that can directly decompose lignin and hemicellulose is relatively slow. The direct use of cellulase for enzymatic treatment cannot effectively hydrolyze the cellulose in the straw; the alkaline method used in pulp and papermaking can effectively remove lignin, but the resulting wastewater pollution is very serious and must be recycled at high cost. Hemicellulose is also damaged; the acid method is prone to produce substances such as furan and small molecular acids that inhibit the growth of yeast; the steam explosion method has high costs, complex products, and tar formation. [0003] Low-concentration lye can quickly swell straw and grass with low lignin content at room temperat...

AI Technical Summary

Problems solved by technology

However, because of the addition of alkali during the treatment process, the cost has increased, and the efficiency of recycling costs and low-concentration alkaline delignification is not ideal.