Straw fiber and process for separating straw fiber by bio-enzyme method

Abstract

The invention belongs to the field of biological pulping and provides straw cellulose. The straw cellulose is characterized in that straw stalk fiber cut and separated by enzyme molecules directionally is well preserved, the result that fine fiber is damaged in the traditional chemical pulping is overcome, the length-weight average value is 0.70 to 1.10 mm, and the quality-weight average value is1.10 to 1.40 mm. The invention further provides straw fiber. The straw fiber comprises the fiber structure of the straw cellulose; the quality of the straw stalk fiber is as follows: the brightness (whiteness) is 57 to 75 percent, the hardness is 7 to 26 K, the folding resistance is 30 to 78 times, the tearing index is 3.0 to 5.5 mN.m<2>/g, and the tensile index is 41.0 to 62.0 N.m/g. The invention further provides a process for separating fiber from straws and application of the straw fiber. High-temperature chemical cooking black liquid is not generated in the production process, the fiber quality (length, whiteness, short fiber content and the like) is obviously more excellent than the quality of the traditional chemical pulping, the pulp yield is increased by 25 percent or higher whenbeing compared with that of the traditional chemical pulping rate, and water consumption and energy consumption in the production process are reduced by 30 percent or higher when being compared with those of the traditional chemical pulping.

Description

technical field [0001] The invention relates to a process for separating straw fibers by a biological enzyme method, which belongs to the field of biological pulping. Background technique [0002] Plant straw is mainly composed of cellulose, hemicellulose and lignin. The outer layer of lignin and the inner layer of cellulose are connected by the middle hemicellulose. There are certain differences in the proportions of the three substances in different plant straws, but Cellulose, which is connected by glucose molecules, accounts for 35-50% of the total mass of straw and is the most abundant component. This fiber is widely used in pulp and paper making, cellulosic ethanol, bio-dye, bio-energy and other fields Among them, pulp and papermaking is a way to consume plant straw in large quantities with high added value. [0003] At present, the separation of fibers in traditional straw (wheat straw, rice straw, corn straw, reed, bagasse, rape stalk, etc.) pulping and papermaking ...

AI Technical Summary

Problems solved by technology

[0004] The characteristics of these two chemical straw pulping processes are: high temperature, high pressure, and extensive use of chemical additives. In the process of delignification, not only the carbohydrate (fiber) is destroyed, the pulp rate is reduced, but more seriously, Difficult-to-handle cooking black liquor is formed during the pulping process. Because the cooking black liquor contains a large amount of lignin and chemicals, it is an extremely difficult industrial high-concentration solid-containing waste liquid, and the existing water treatment cannot be used. Technology to solve the pollution problem of cooking black liquor

[0005] At present, there are two main treatment methods for straw pulping and cooking black liquor: one is the alkali recovery process, but the problem of secondary treatment of papermaking white mud has arisen in the process; the other is to concentrate the cooking black liquor and compound nutrients before spraying Pelleting produces lignin fulvic acid fertilizer, but VOCs and NH are produced due to high temperature drying process in spray granulation 3 The foul smelling smoke causes secondary pollution. At present, there is no reasonable way to control the black liquor from straw pulping and cooking. The development of a new green separation process for straw fiber is the goal pursued by researchers and manufacturers.

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