Patent ID: 8366876

Claim:
A method for the improvement of a wash after a completed digestion process in a digester for the production of cellulose pulp, comprising: digested softened chips passing a final strainer-section at a bottom of the digester, feeding out the digested softened chips from a bottom surface of the digester, subsequently feeding out the digested softened chips under an influence of a rotatable bottom scraper arranged at the bottom of the digester and thereafter through a bucket-shaped outlet tap below the bottom of the digester, providing the bucket-shaped outlet tap with a central shaft extending therethrough, the shaft having nozzles defined therein, establishing a radially directed displacement wash in a flow of the digested softened chips through the bucket-shaped outlet tap, the radially directed displacement wash being established between the nozzles and a screen surface of a wall of the bucket-shaped outlet tap, subjecting the digested softened chips to the radially directed displacement wash in the bucket-shaped outlet tap, conveying the digested softened chips onwards to an outlet line connected to the bucket-shaped outlet tap, passing the digested softened chips through a blow-valve arranged in the outlet line, establishing a fall in pressure of at least 0.5 bar and at most 3 bar across the blow-valve, and the fall in pressure across the blow-valve defibrating the digested softened chips.