A New Sensor Based Approach to Brown Stock Washer Optimization

摘要

The fundamental purpose of the brown stock washer operation has remained unchanged and that is to economically remove the maximum amount of dissolved organic and soluble inorganic material present in the pulp mass at the end of the washers while minimizing the amount of fresh or recycled water used. Dilution factor has been shown to be one of the important variables that can be used to control this economic optimum. Expressing washer losses to calculate washing efficiency has traditionally relied on measuring the conductivity either of the last stage filtrate or occasionally of the pulp mat. Research has shown that this is not as accurate as it could be and a new method has been developed that measures directly in the pulp mass in a continuous fashion. Combined with the important measurement of feed consistency, the tonnage rate and washer loading is also properly managed and optimum shower flows are calculated. A case study will be presented. With environmental, energy and chemical consumption pressures increasing, optimization of the brown stock washing operations will definitely contribute to a competitive advantage.