Equipment is used at wastewater treatment plants not rich in water for belts splashing purposes and water filtered out from sludge has to be utilized, or at these ones coping troubles due to the facility loading or silting by drained polluted filtrate.
The equipment is designed for:
treatment of filtrate drained from under belt press,
filtrate purification of sludge residues coming from sieves splashing,
preparation of water for sieves splashing.
Filtrate is pumped from a tub underneath the press by submersible pump and fed through a pipe into a mixer (pos. 2). Before entering the mixer some air is added into the filtrate by an aerator (pos. 8). In the mixer there the air is mixed with the filtrate. The aerated filtrate passes through a drainpipe (pos. 3) into the tank (pos. 1) that is divided by a partition in two sections. Sludge particles from the filtrate in consequence of its saturation with the air rise up toward the surface in the first section of the tank. Rake conveyor (pos. 5) takes the buoyed up sludge and conveys it in a sludge collector (pos. 6). After the sludge collector filling a mixer (pos. 5) and a sludge pump (pos. 7) automatically start to operate and deliver the collected sludge back to the belt press flocculation unit. Thickened sludge from the cleansed filtrate gets back on the belt press inlet by the sludge pump: volume of the sludge returned back has no impact on the pressing process. The purified water passes in the second section of the tank and across a weir crest into a splashing water tank. Through a flange (pos. 10) the water is delivered to the splashing water pump. Unnecessary water passes through the flange (pos. 9) into sewage.
Two outlet holes (pos. 11) with ball valves serve for the tank (its section) cleaning and thorough draining.
The insoluble matter content of the purified filtrate is tenth of that on the equipment entry.