ABSTRACT
The biggest issue before pulp and paper producers is availability of quality raw material. India is fiber deficit country, this message has become more intense after covid when price of different raw materials are increased by 20-25%, . Chemical pulp is produced by chemical delignification of wood and non-wood plants. After kraft pulping the remaining lignin is removed by oxygen delignification and bleaching to produce higher purity cellulosic pulp. The goal of delignification processes is to remove lignin from the raw material without a negative effect on the cellulose and strength of pulp. The economics of pulp and paper production is more related to the yield of unbleached and bleached pulp production. Marginal increment in pulp yield reflects into savings of crore of rupees on yearly basis. An overall vigilant concern on process conditions and variables is required during production of pulp. BAT technology for pulping along with utilization of various additives and pretreatment methods allow to fine tune these process to obtain pulp with desired yield and quality. The primary aim of this paper is to review different process variables in respect to the yield of the pulp. © 2022 Indian Pulp and Paper Technical Association. All rights reserved.