A pretreatment method for high efficiency saccharification of lignocellulose

Abstract

The invention discloses a pretreatment method for high efficiency saccharification of lignocellulose and especially relates to a pretreatment method for lignocellulose with low concentration alkali lye at the normal temperature. The method is characterized by including steps of coarse cracking, alkaline liquid wet grinding, alkali recovery and enzymatic hydrolysis, the lignocellulose raw materialafter coarse cracking mixes with the monovalent metal alkaline liquid with the concentration of 0.1-3%, after the wet method crushing is performed at the normal temperature and the solid and liquid are separated, the liquid is used for recovering the monovalent metal alkali, the solid is modification lignocellulose and further enzymatic hydrolysis is performed on the solid, and the sugar solutionis prepared. The lignocellulose is regarded as raw material, the normal temperature condition without outside heating can be selected, pretreatment is performed on the alkali lye solution with low concentration, alkali lye can be effectively recovered, the enzymatic hydrolysis efficiency of the raw material is improved, the sugar yield of the raw material is improved, the cost is effectively reduced, the economy is improved, and the deficiency of large energy consumption low sugar yield and high requirements for the device in the existing lignocellulose pretreatment method are made up.

Description

technical field [0001] The invention belongs to the technical field of biochemical industry, and in particular relates to a pretreatment method for high-efficiency saccharification of lignocellulose, in particular to an energy-saving and environment-friendly normal-temperature low-concentration alkali pretreatment method. Background technique [0002] With the depletion of global oil resources, serious atmospheric carbon dioxide pollution and economic development, it has become an inevitable trend to use biomass raw materials to produce bioenergy and biochemical products to replace petrochemical products. At present, the production of most biochemical products depends on the raw materials of food crops such as sugarcane and corn, which has the disadvantage of high production cost and can only be applied in a few high value-added fields. In addition, the use of food crops as raw materials for biofuel production has the danger of triggering and aggravating food problems. The ...

AI Technical Summary

Problems solved by technology

Currently lignocellulose pretreatment methods include physical methods (such as pulverization), chemical methods (such as acid and alkali treatment), physicochemical methods (such as steam explosion) and biological methods, but these processing methods have the following problems: physical methods such as The energy consumption of a single pulverization process is high, accounting for about 50% to 60% of the total energy consumption in the lignocellulose saccharification process; the acid or alkali concentration required for chemical pretreatment is 10% to 77%, and the treatment temperature is 100°C to 120°C , has the disadvantages of high energy consumption and high requirements for equipment corrosion resistance; the loss of hemicellulose after treatment by physical and chemical methods such as steam explosion method reaches 60% to 70%, and the solid yield of raw materials is only 30% to 50%, which greatly reduces Sugar yield and raw material utilization rate; the reaction period of the biological method is long, and at the same time, the bacteria will use part of the cellulose and hemicellulose, which will reduce the hydrolysis yield

[0004] The problems existing in the prior art can be attributed to: (1) heat treatment methods are used, the energy consumption is high, and the sugar yield is low; Combination of operations, but the production cost also increases accordingly; (3) acid hydrolysis or alkali hydrolysis methods are generally used, but the acid / alkali concentration is higher than 3%, the maintenance and maintenance costs of equipment, and the extensive use of acid / alkali, And problems such as unreacted acid / alkali can't be reclaimed, all increased production cost; (4) the method that has has used cheap and easy-to-get Ca(OH) 2 Alkaline hydrolysis, and the CaSO produced in the process 4 and other by-products, resulting in environmental burden