The screenings are deposited into the compactor hopper from which a rotating shafted spiral conveys the solids to the compacting zone where they are dewatered and, at the same time, conveyed to the outlet. The compacting zone is equipped with spray nozzles for washing organic matter contained in the screenings. The liquid produced by washing and compacting is transferred back to the purification process through the screening channel.
A Compactor Washer is similarly engineered to a Screw Compactor with the primary differentiation being that the Screw Washpactor is equipped with a separate waste screening wash zone. The Washpactor is designed to separate valuable organics from screenings waste. The organics can be returned to the wastewater process to increase the organic loading present in the flow, and can further be used later on in the plant biological process. The wash chamber is mounted above the compaction screw which is fitted with a mechanical mixer and thus liquidizes the organics in the screening waste. The washed screening waste is then conveyed and compacted by means of a screw, which de-waters the screenings waste to a liquid content of approximately 50% by mass. The compactor screw starts to compact the clean screenings to be discharged into a bin container or plastic bag. On completion of the compaction cycle, the system starts from the beginning again.