Effect Of Enzymatic Assisted Treatment On Latency Removal Of High Yield Pulp

High yield pulp gets the more and more favour of papermaking industry, becauseof its high yield, less pollution, low energy consumption, low investment in equipmentand many other advantages. But high concentration of refining in pulping processmake pulp fibers stiff and ankylosis for generating the heat and the high temperaturepulses in this stage for the high yield pulp, and the process make the fiber the latencystate, which can affect the strength properties of the pulp. Therefore, high yield pulpproduction process must eliminate latency, latency removal can affect properties of thepulp, so we need to explore effective the way of latency removal in order to improvethe performance of high-yield pulp. Conventional latency removal process conditions:pulp consistency of2%, pH of7.0, the temperature of80°C, the reaction time of30minutes, the process needs the large energy consumption, and the latency removal isnot ideal. To solve this problem, this article studied on the effect of enzymatic assistedlatency removal of high yield pulp (mainly APMP).The results showed that the APMP pulp adds cellulase and alkaline xylanase inthe process of delatency, which makes the fiber of the kink index and bending reducein varying degrees. But joining in the acidic xylanase increased fiber latency ofexistence. So the paper studied the effect of xylanase enzyme assisted latency removalof high yield pulp under the alkaline conditions.Study on the effect of adding cellulase and alkaline xylanase enzyme in theprocess of latency removal for the the APMP pulp, and enzyme treatment conditionwas optimized. Adding the cellulase enzymatic optimal conditions in the process of thedelatency: the amount of enzyme of3.0IU/g pulp, pulp consistency of2%, pH of7.0,temperature is70°C, the reaction time of20minutes. The kink index and bendingindex under this condition than conventional elimination latency decreased by25.21%and23.53%respectively. Adding alkaline xylanase enzyme optimal conditions in theprocess of the delatency: the amount of enzyme of10.0IU/g pulp, pulp consistency of2%, pH of8.0, temperature is60°C, the reaction time of30minutes. The kink indexand bending index under this condition than conventional elimination latent decreasedby11.86%and9.72%respectively. Cellulose enzyme added the APMP pulp make thedelatency better.Discussion of adding the enzyme latency removal the combined effects fordelatency and the physical properties in the process of the delatency. Adding the cellulase enzymatic optimal conditions for the physical properties in the process of thedelatency: the enzyme dosage2.0IU/g, and a temperature of60°C, pulp consistency2%,time of20min, the pH value of7. The latent effect of the elimination of the paperbetter, and the physical properties better. Under this condition, compared with theconventional elimination latent bursting index increased17.12%, breaking length of29.09%, tear index is increased by4.75%. Experimental results show that, APMP pulpadds the cellulase enzyme in the latent elimination process, a latent state of the pulpcan be reduced, help eliminate latent, but the enzyme dosage or the latent state toeliminate is too large, which can reduce the physical properties of APMP pulp. soenzymatic delatency must control the rang in a moderate range.The alkaline xylanase enzyme of delatency, the amount of enzyme impacts tearindex and burst index of the main factors. Temperature is a major factor for impactingthe the paper optical performance (whiteness, opacity and light scattering coefficient),breaking length and degree change. Pulp consistency, pH value and the time of thedelatency is less affected.for the optical and physical properties of the pulpConsidering the beating energy, optical properties and physical properties of the pulp,as well as latendy removal. Adding alkaline xylanase optimal conditions in the processof the delatency: the amount of enzyme of5.0IU/g pulp, pulp consistency of2%, pH of8.0, temperature is60°C, the reaction time of30minutes. With the same cellulasetreatment results, the high amount of enzyme will reduce the physical properties ofpulp.Cellulose enzymatic delatency degree of swelling best conditions: the amount ofenzyme of3.0IU/g, pulp consistency of2%, pH of7.0, temperature of60°C, and thereaction time of20minutes. Xylanase enzymatic delatency degree of swelling best ofconditions: the amount of enzymetic10.0IU/g, pulp consistency of2%, pH value of8.0, the temperature of60°C, reaction time of30minutes. Enzymatic delatencyaffecting the pulp swelling and the latency removal in the certain degree of relevance,which has some sort of connection of the degree of swelling can indirectly reflect thedelatency of the good or bad.