Authors:Daisy Biswas, M. Misbahuddin, Nazma Khatun, U. Roy
Abstract:The use of wood along with bamboos is now new a dimension of research for decreasing the raw material crisisin pulp industry to run the mill to itsfull daily production capacity. With this aim, kraft pulping ofAlbizia richardiana (rajkoroi) wood speciesin a mixture with Bambusa vulgaris(baizzya) was assessed to incorporate the formerspecies as pulping raw material. Chemical analysisshowed that alphacellulose content of B. vulgaris is low but lignin content is high compared to A. richardiana. Pulps were made in kraft process maintaining 25% sulphidity by varying the alkali doses. The temperature was maintained at 170°C during pulping. The chip in the mixture were in the ratio of B. vulgaris : A. richardiana (100:00; 70:30; 50:50; 30:70 and 00:100). Hand sheets were made and the physical strength propertieslikely tear, tensile and burst were evaluated at two freenesslevel. The active alkali requirement for bamboo was higherthan A.richardiana forsame degree of delignification. The pulp yield waslowbut superior quality pulp could be obtained from B. vulgaris. On the other hand pulp yield for A. richardiana was high but qualitywaslow. Mixing ofB. vulgaris chipsin a proportion of 30%, pulp yield decreased but strength properties like tear, tensile and burst increased. On further increase of bamboo chips in the furnish, a similar trend was observed. The optimum ratio of chips of B. vulgaris: A.richardiana could be either 30:70 or 50:50 based on pulp yield and quality. The pulp making characteristics of the two species being different, further research on blending the pulps together after individual cooking of the speciesis recommended
Keywords:Albizia richardiana, Bambusa vulgaris, kraft pulping, pulp yield, strength properties