Method for treating lignocellulosic biomass with ammonia combined with dilute alkali and normal pressure

Abstract

The invention discloses a method for processing lignocellulosic biomass at the constant pressure with ammonia and diluted alkali combined and belongs to the field of biomass energy processing and application. The method comprises the following steps of the step 1, taking and cutting up dry lignocellulosic biomass, the step 2, preheating the lignocellulosic biomass to 40 DEG C to 60 DEG C, adding the certain amount of ammonia, adding moderate water vapor, insulating at the temperature of 40 DEG C to 60 DEG C for 1 to 4h in a sealed mode, or taking the lignocellulosic biomass and fumigating the lignocellulosic biomass by stronger ammonia water at the temperature of 40 DEG C to 60 DEG C for 1-4h, and the step 3, stirring the lignocellulosic biomass processed in the step 2 with diluted alkali solution at the temperature of 40 DEG C to 100 DEG C for 1-10h, filtering and washing the lignocellulosic biomass to be neutral to obtain lignocellulosic to be reserved. The lignosellulosic content of the lignocelulosic biomass processed by the method is smaller than or equal to 2%, and the glycation rate is not lower than 87%. Prepared glycation liquid has no restrain on following fermentation, can be used for fermenting and producing alcohol, lactic acid, feed protein and the like or be directly used for preparing feed sugar, and can be used as microcrystalline cellulose or raw materials of papermaking pulp.

Description

technical field [0001] The invention belongs to the field of pretreatment and application of biomass energy, and uses ammonia combined with dilute alkali to treat lignocellulosic biomass under normal pressure and lower temperature conditions to prepare lignocellulose that is easy to saccharify and has a high sugar yield. Background technique [0002] Lignocellulosic biomass crop straw is a crop residue with a high fiber content after the seeds are harvested, including cereals, beans, potatoes, oilseeds, hemp, and cotton, sugarcane, tobacco, melons, etc. crop straw. my country's rice straw resources are very rich, and the output is huge, the main components are cellulose, hemicellulose, lignin and some soluble substances. Among them, cellulose is the main source of fermentable sugar, which accounts for about 30-45%. Fermentable sugar can be further converted into liquid fuels or chemical raw materials such as ethanol, acetone, butanol, and acetic acid through microbial ferme...

AI Technical Summary

Problems solved by technology

In these two pretreatment methods, steam explosion has a certain degree of hydrolysis on the cellulose and hemicellulose in the straw, and the loss rate of hemicellulose is high, and lignin is mixed in it and it is difficult to sort and remove.

The ammonia explosion method is very effective and controllable in removing lignin, and at the same time, the loss of hemicellulose is small, and the by-products produced are also few, but the high ammonia and its recovery energy consumption make it difficult to promote

Nankai University Liu Le et al. (Chinese patent CN 102660884A publication date 2012.09.12) used ammonia water instead of traditional liquid ammonia to carry out steam explosion at 140-160°C (0.4-0.6MPa). Although the process of this method is simpler than the traditional liquid ammonia method, but High temperature is still required and the amount of ammonia water is large, and at least 15mL ammonia water is required for every 1g of straw powder

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