slow sand filter


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slow sand filter

[′slō ′sand ‚fil·tər]
(civil engineering)
A bed of fine sand 20-48 inches (151-122 centimeters) deep through which water, being made suitable for human consumption and other purposes, is passed at a fairly low rate, 2,500,000 to 10,000,000 gallons per acre (23,000 to 94,000 cubic meters per hectare); an underdrain system of graded gravel and perforated pipes carries the water from the filters to the point of discharge.
References in periodicals archive ?
One of the more labor intensive maintenance activities in operating a slow sand filter is scraping of the filters to remove the schmutzdecke (biological layer that provides the treatment).
deep and made of larger grains of sand (0.3 mm to 0.5 mm) than the traditional slow sand filter. This allows greater penetration of the media and more solids storage during the filter cycle.
Tenders are invited for Construction of slow sand filter bed 184.31 square metre, construction of sedimentation tank of 60,000 litres capacity and construction
54 construction of rcc glr having 10 kl capacity with psp &; cwt and sump well with slow sand filter plant &; single phase at village didiya khurd under mjsa phase iii
Tenders are invited for Supplying and filling filter media sand in slow sand filter (02 units) at gc crpf nagpur
The complete purification process typically includes physical processes such as filtration, sedimentation, and distillation, biological processes such as slow sand filters or biologically active carbon, chemical processes such as flocculation and chlorination and the use of electromagnetic radiation such as ultraviolet light.
Water treatment plants (rapid and slow sand filters) in Pakistan are not designed to remove pesticides.
The water is then treated using CoCoDAFF and passes through post-ozone and granular activated carbon (GAC) contactors, as well as slow sand filters before arriving at the disinfection stage, where sodium hypochlorite is introduced to contact tanks in doses using 520 series Watson-Marlow pumps.
Water filtration practices; including slow sand filters and precoat filtration.
Slow Sand Filters. This system, introduced into the U.S.
These are rapid sand and slow sand filters using granular media and diatomaceous earth filters using a powder-like media.
Slow sand filters depend on biological activity for operation.