The Effects Of Enzymes On The Fiber Traits And Paper Properties Of Wheat Straw Pulp

Pulp and paper industry has been faced with raw materials, energy and pollution,the three problems are becoming outstanding.Improve the papermaking process, optimize process parameters is becoming increasingly urgent. The energy conservation, pollution reduction has been rapid development with the biotechnology. The enzyme is diversity and specificity so that it is widely used in the paper industry.Enzymes used in paper industry has becoming a new generation of energy-saving.The effects of cellulose and xylanase on KP of wheat straw were studied by fiber and paper performance.This object was by experimental conditions,for the pulp was treated by different enzyme dosages and different times.The pulp and paper performance were measured after treatment to determine the optimal amount of enzyme dosages and treated times.After the optimal amount was determined,orthogonal experiment was conducted with cellulose,xylansse and treated times.The result of orthogonal experiment was showed by fiber performance.The degradation mechanism of cellulose and xylanase was studied by IR, SEM and ion chromatography.KP of wheat straw was treated by cellulose,the results were showed by fiber length,fines, beating degree and paper performance. The results showed that the optimal treatment conditions are cellulose dosage 6IU/g, treatment time 60 min. Under this condition, the treated slurry pulp compared to the untreated,the fiber length and fines component have little changes,but beating degree has significantly increased, especially when beating revolutions were2000 r, the treated pulp has a 38.5 percent increase than the untreated pulp, the paper burst index and tear index is the maximum at this time.The optimal treatment conditions of the xylanase treatment are xylanase dosage 30IU/g, treatment time 90 min. Under this condition,the weighted average length of treated pulp increased by 5% than the untreated,the fines component decreased by 3.3%. At this time,the beating degree appeared the lowest values.The optimal treatment conditions of orthogonal experiment are cellulose dosage4IU/g,xylanase dosage 40IU/g, treatment time 60 min.The fines of KP wheat straw was degraded by cellulose,so that the surface of fiber becomes smoother. The fiber non-crystalline regions and crystalline regions are destroyed by cellulose so that fibers are easier to sub-wire broom. The part of hemicellulose were degraded by xylanase, the fines content from pulp were reduced. The fiber non-crystalline regions were destroyed so that the pulp brightness was increased. The content of crystalline regions was increased, so that fibers were harder to sub-wire broom. By ion chromatography analysis,it shows that there are a large number of micro-organisms in enzyme solutions. The pulp after enzyme treatment should to be sterilized as soon as possible.