Using white liquor as the alkali source in oxygen delignification

摘要

This paper considers the potential impact on oxygen delignification stage performance when unoxidized white liquor and partially oxidized white liquor containing thiosulfate, or (OWL[T]), are used as the alkali source. A literature review was conducted to estimate the oxygen consumption of the pulp, the raw black liquor carryover, and the sulfur compounds in the charged white liquor and in the postoxygen washer filtrate recirculated to the oxygen stage. These values were used to calculate the total oxygen consumption (kg O-2/bone dry ton [BDT]) as a function of oxygen stage. kappa. The maximum oxygen charge was estimated using the generally accepted void volume (X-g) limit of 20%.