METHOD FOR FILTERING A PRODUCT FORMED IN CAUSTICIZATION
The invention concerns a method for filtering a product formed in a causticization process, in which filtration process the product is subjected to separation of the filtrate from the solids. The product received from a causticization tank is routed to a filter, where the filtrate is separated from the product to be filtered and the solids content of the remaining solids cake is increased by drying the cake, after which the cake is washed with water and dried. The invention is characterized in that the filtrate separated from the product in the filter is combined with the washing filtrate obtained from the washing and drying steps of the filtration process, and the primary liquor thus obtained is routed into a digester for use as cooking liquor.