Coarse substances removal from waste water involves filtering water using net bags alternately filled and suspended within covered cistern for release to sediment basin

摘要

In a process and assembly to remove coarse materials and sludge from domestic and trade waste water, waste water is released with paper, fibres, plastic and other coarse items into a filter sack (5) . Sludge and sand particles are collected in a trap under the sack. A mixture of water and sludge is abstracted by a submerged pump (11) to a separate sedimentation basin with a reed bed, plus a drainage layer and outlet to a biological cleaning stage. Preferred Features: The sub-surface cistern (1) contains two or more filter bags (8). The bags are filled alternately, giving each time to drain and dry before emptying. The covered sedimentation basin is sub-divided by screens or walls into two or more sections (16) which are alternately linked to the incoming water supply. Both the cistern (1) and sediment basin have rigid safety covers.