Purification of condensate from evaporator and cooker in sulfate pulping process, comprises addition of acidifying agent to methanol column used to remove ammonia

摘要

An acidifying agent is added to the methanol column (17) used to remove ammonia from the condensate (1). A method for preparing sulfate pulp includes steps for reducing nitrogen oxide (NOx) emissions and obtaining a flow of ammonia-rich liquid by using a stripper (15) and a methanol column to purify the condensate, which generates a volatile methanol fraction. An acidifying agent is added to the methanol column.