Sieve assembly for papermaking fibre suspension

摘要

The sorting assembly to clean a fibre suspension of impurities, for papermaking pulp, has a fixed sieve body with rotary symmetry with paddle blades rotating at its inner surface. An initial sieve is in the fibre suspension flow path between the inlet and the sieve body, covering the end side of the sieve body at the inlet end. It divides the housing into a feed zone and a working zone. The entry side of the initial sieve is scraped by a cleaner. Preferably the fibre suspension inlet is at a tangent to the housing. The outlet for separated matter for rejection is at each end of the working zones opposite to the inlet zones. The sieve body encloses a rotor body with rotation symmetry, which forms a ring zone together with the sieve body. The rotor body carries a sorting paddle, and is blocked at the inflow side. The rotor body is on a vertical axis. A connecting channel is between the fibre suspension inlet and the outlet for the sorted suspension, containing an adjustable or controlled barrier. An adjustable or controlled diaphragm is at the opening of the connecting channel into the suspension inlet. A single drive shaft, on a floating bearing, powers the sorting paddles or rotating body and the scraper for the initial sieve.