Operating Experience of Acid Treatment and Ozone ECF Bleaching

Abstract

Kraft pulp section of Yatsushiro mill consists of two fiber lines and both lines were converted to ECF bleaching sequence in 2003. Medium consistency ozone bleaching with an acid treatment (A stage) prior to ozone bleaching stage was introduced to the fiber line #2 for hardwood. This A stage is the first commercial application in Japan to prevent diffuser washer from scaling.
This report shows the mill experience of A stage and Ozone ECF bleaching.