A method for simultaneously preparing cellulose fiber and hemicellulose solution

Abstract

The invention discloses a method for preparing cellulosic fibers and a hemicellulose solution simultaneously. The method comprises the steps that 1, high-whiteness chemical pulp is impregnated with cold alkali liquid with a certain concentration; 2, after cold alkali impregnating is finished, the high-purity cellulosic fibers and cold alkali filtrate are efficiently separated through a twin-roll squeezer, and cold alkali impregnating is conducted on next-batch chemical pulp through the obtained cold alkali filtrate and a small amount of sodium carbonate liquid; 3, in a similar way, the cold alkali filtrate is constantly recycled and the sodium carbonate liquid is supplemented for cold alkali extraction of multiple batches of chemical pulp; 4, all batches of obtained high-whiteness cellulosic fibers are mixed to be uniform through a pulp mixer and then fed into a washing workshop section; 5, after the concentration of hemicellulose in the obtained cold alkali filtrate reaches an upper limit value, the cold alkali filtrate is fed into a hemicellulose extraction workshop section. The method has the advantages that by adopting the technology that the hemicellulose in the high-whiteness cellulosic fibers is extracted by recycling the cold alkali filtrate multiple times, green and environmental friendliness, economical feasibility and efficient utilization of plant sources are achieved.

Description

technical field [0001] The present invention relates to the fields of pulping, papermaking and textile industry, in particular to a method for simultaneously preparing cellulose fiber and hemicellulose solution. Background technique [0002] Dissolving pulp, also known as cellulose fiber, is a high-purity bleached chemical pulp with a content of methyl fiber generally higher than 90%. It is mainly used to prepare high value-added cellulose ester and cellulose ether products. The purity of dissolving pulp is the guarantee of the yield of cellulose derivatives, the higher the purity, the greater the yield. In addition, high-purity dissolving pulp can ensure higher product yield and lower dosage of derivatizing reagents when preparing cellulose derivatives. Therefore, the purification of dissolving pulp is crucial for its use in the manufacture of high value-added cellulose products. At present, there are many purification methods for dissolving pulp, such as nitren extractio...

AI Technical Summary

Problems solved by technology

However, because the membrane modules are expensive, and the concentration of alkaline solution after purification is generally not high, if it is reused to purify the dissolving pulp, it is necessary to add concentration equipment

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