クラフト蒸解に関する化学工学的基礎研究

第3報パルプ粘度における蒸解条件の影響

抄録

It is very important to understand the relationship between kraft cooking conditions and pulp characteristics (pulp viscosity, lignin free pulp yield) for the purpose of obtaining the kraft pulp with good quality at high yield.
The chips of Fagus crenata Blume (Buna) and Pinus densiflora S. et Z.(Akamatsu) were cooked and we could exactly set up cooking conditioas by using experimental apparatus at high liquor to wood ratio. The experimetal data were analysed by using statistical method. The following useful informations were consequently obtained.
(1) The effective cooking factors on pulp viscosity were cooking temperature, alkali concentration and cooking time, but hydrosulfide ion concentration and chip thickness were not so effective from estimation of proportion of variance.
(2) It is very effective to drop cooking temperature, to drop alkali concentration and to shorten cooking time for the purpose of raising kraft pulp viscosity.
(3) Raising 1ignin free pulp yield is often incompatible with mising kraft pulp viscosity.
Tberefore, it is very important to set up the most suitable cooking conditions which are fitted to each use of kraft pulp.