Method for producing fuel ethanol by secondary fermentation after kudzu root steam explosion pretreatment

Abstract

The invention relates to a method for production of fuel ethanol through steam explosion pretreatment and secondary fermentation, which comprises the following steps: Kudzu roots are processed by means of steam explosion for 2 to 4 minutes under steam pressure of 0.5 to 1.0MPa; maltogenic amylase is added into the Kudzu roots after steam explosion treatment for saccharification, and (NH4)2SO4, KH2PO4 and yeasts after activation are simultaneously added into the Kudzu roots under aseptic condition for anaerobic fermentation by 48 to 60 hours; ethanol generated by fermentation is distilled and collected; steam explosion technology with short time (2 to 4 minutes) and low pressure (0.5 to 0.8) is adopted for pretreatment of the Kudzu roots, thereby the long-term cooking process (30 to 120 minutes) of starchy materials is left out and energy consumption of fermentation production of the ethanol is reduced. The Kudzu roots after steam explosion treatment are directly fermented after saccharification, and no water is needed to add otherwise, thereby the invention has the advantages of capability of improving ethanol content in beers, reduction of energy consumption of distillation, reduction of treatment of subsequent waste water, reduction of production cost, and favorability for comprehensive utilization of the Kudzu roots.

Description

technical field [0001] The process belongs to the utilization of kudzu root resources, and particularly relates to a method for producing fuel ethanol by fermentation of kudzu root after steam explosion pretreatment. Background technique [0002] Radix Pueraria (Radix Pueraria) is the underground root of Pueraria, which is a perennial leguminous vine. There are more than 30 species of Pueraria in the world, distributed in China, Japan, Southeast Asia and other countries. There are about 9 species and 2 varieties in my country, which is the distribution center of Pueraria. Pueraria resources are distributed all over the country, such as Pueraria (P.Lobata (will) Ohwi), Pueraria (P.Thomsoni Berth), Pueraria (P.edulis Pamp), Pueraria (P.Omeiensis Wang), Yunnan kudzu (P.peduncularis Crah.ex Benth), among which kudzu and kudzu are the most common and have the largest amount of resources. Pueraria is rich in starch, and the starch content of fresh pueraria reaches 18.5-27.5%, wh...

AI Technical Summary

Problems solved by technology

The kudzu root after the optimized low-pressure steam explosion treatment can be directly fermented to produce ethanol, which solves the problem that a large amount of energy needs to be consumed for kudzu root crushing and starch cooking and liquefaction before the kudzu starch is fermented for ethanol.