IMPACT OF COOKING CONDITIONS ON PULP YIELD AND OTHER PARAMETERS
Two laboratory studies using multiple white liquor additions and multiple black liquor extractions were carried out to investigate the impact of cooking conditions on pulp yield and other parameters. Results from the first study (alkali profiles at a constant cooking temperature) indicate that cellulose yield shows a good correlation with pulp yield and is significantly affected by alkali profiles. A higher alkali charge to the impregnation stage shows the most negative impact on cellulose yield. There is no significant difference in xylan yield between different alkali profiles. In addition, it was found that xylan content does not correlate with the pulp yield. In spite of obtaining higher cellulose yield when adding more alkali in the wash zone, a lower pulp yield is obtained at a given kappa number due to lower delignification rate. The results from the second study indicates that cooking temperature does not affect the pulp yield at a given kappa number, but lower pulp viscosity is obtained from a higher temperature cook. The positive effect of higher Hfactor at a higher cooking temperature on pulp yield and pulp viscosity is also reported. Both unbleached pulp cellulose yield and pulp viscosity affect the bleached pulp tensile index. However, unbleached pulp cellulose yield shows a better correlation than pulp viscosity. Xylan content of pulp does not show any effect on tensile index of either unbleached or bleached pulps.
white liquor black liquor cooking cellulose yield pulp yield
Nam Hee Shin Bertil Stromberg
Andritz Inc, 13 Pruyns Island Drive, Glens Falls, NY 12801, USA
国际会议
广州
英文
209-216
2006-11-08（万方平台首次上网日期，不代表论文的发表时间）