Study On Pulping Technology Of Agricultural Straw Combined With Hydrothermal Method And Enzymatic Treatment

With the implementation of the national decree banning the import of solid waste,the raw materials of waste paper used for papermaking are in sharp shortage.Using agricultural straw with wide source and low price as raw materials for papermaking can effectively alleviate this problem.Based on high-yield pulping technology of corn stover by hydrothermal method,the effects of enzyme treatment on the properties of corn stover high yield pulp and hydrolysate were further discussed.At the same time,the effect of sieving on the properties of corn stover high yield pulp was discussed..After hydrothermal treatment,adding cellulase or xylanase to corn stover high-yield pulp before and after refining,respectively,could improve its drainage performance and the concentration of sugars in the hydrolyzate,but it had an adverse effect on pulp strength.When the enzyme dosage was less than 15u/g,the enzymatic treatment before and after refining could significantly improve the water drainage performance of corn stover high-yield pulp and increased the concentration of sugars in the hydrolyzate,and had little effect on the pulp strength.Under the same conditions,compared with the post-refining enzymatic treatment,the pre-refining enzymatic treatment had a more significant improvement in the drainage performance of corn stover high-yield pulp,but had a greater adverse effect on the fiber quality and pulp strength.When the enzyme dosage was the same,compared with the xylanase treatment,the cellulase treatment had a better effect on improving the drainage performance of the high-yield corn stover pulp,and significantly increased the sugar concentration in the hydrolyzate,but the adverse effect on pulp strength was greater.Adding ferulic acid esterase in the process of cellulase or xylanase treatment could further improve the treatment effectiveness.When the dosage of ferulic acid esterase was0.5g/kg,it could improve the drainage performance of high yield corn stover pulp while ensuring the pulp strength.The obtained hydrolyzate had a higher antioxidant and sugar concentration.The sieving results of the obtained corn stover high-yield pulp showed that the P200/R350 and the R30 fractions had the greatest impact on the mechanical strength of the corn stover high-yield pulp.Except for the P350 fraction,the smaller size of fraction was,the larger beating degree and water retention value of t fraction were.The dewatering performance of corn stover high-yield pulp would be significantly improved by removing the P100/R200 and P200/R350 fractions from pulp.Therefore,combining enzymatic treatment with hydrothermal high yield pulping process,agricultural straw high yield pulp with excellent performance can be obtained,which provides a new idea for the development of non-wood pulping technology.