GB1482266A - Waste treatment plant - Google Patents

Abstract

1482266 Comminuting sewage FOSTER WHEELER POWER PRODUCTS Ltd 31 Oct 1975 [17 Sept 1974] 40516/74 Heading B2A Apparatus A Fig. 1 for comminuting sewage comprises a tank divided into an upstream compartment 1A and a downstream compartment 9 by a weir 8. Water and solid waste are fed into the upstream compartment via inlets 3, 5 respectively. The downstream compartment contains a comminuting device 10 including cooperating blades. The weir retains dense material, the lighter and relatively-easily comminutable material passing over the weir and being ground to a slurry by the comminuting device 10. As described the compartment 1A contains a beater-type comminutor 2. Ground material is discharged via sizing holes, not shown in the comminutor 2 and a pipe 6 and pump 7. The product of the device 10 is recycled by a pump 11. Water level is sensed by a device 4 which controls a water-supply valve 3. The tanks can be emptied by valves 15, 16 and cleaned via doors 17, 18. A rake or conveyor may be used to remove heavy unground material. In a second embodiment such a conveyor 39 Fig. 2 discharges on to a perforate tray 40 and is washed by a spray 22 which also supplies water. Slurry may be recycled to the bottom of the upstream compartment 25. The finally cominuted slurry may be dewatered in a separator 30. Beater type comminutors, not shown may be fitted in the upstream compartment and additional comminutors may also be fitted in the downstream compartment 32. In all cases, a preliminary shredder may precede the apparatus.