| 摘要 |
The incoming liq. suspension is fed into a mass of sludge into which suspended solids settle and above which clarified liq. rises. A down pipe feeds suspension into a bed of sludge, the down pipe being supplied by a slide branch while the top of the down pipe is open to atmos. A fraction of the incoming suspension rises up the downpipe above the branch because of back pressure from sludge tending to seal the bottom of the down pipe; this fraction provides a hydrostatic pressure head to encourage circulation of the sludge. Circulating sludge mixes with liq leaving the down pipe and some of the mixture is directed radially outwards above the surface level of the sludge. The mixt. pref. passes up an annular riser fitted coaxially around the down pipe and perforated to direct some of the mixt. radially outward above the sludge bed. Used for treating slurries discharged as effluent from metallurgical, metal-working, machining and electroplating industries. Sludge thickening and clarification of liq. for the chemical industry. Purificn. of polluted effluent from food processing and papermaking factories; Concn of crystals, e.g. sugar, between crystallisation and centrifuging; Treatment of industrial and domestic waste waters. Circulation produced without pumps or sets so that turbulence is avoided, flocculation improved. |
