Biological rapid sand filters are often used to remove ammonium from groundwater for drinking water supply. They often operate under dynamic substrate and hydraulic loading conditions, which can lead to increased levels of ammonium and nitrite in the effluent. To determine the maximum nitrification rates and safe operating windows of rapid sand filters, a pilot scale rapid sand filter was used ...

This study describes the new design and function of a modified version of a traditional slow sand filter. The Submerged Pond Sand Filter is built inside a pond and has a vertical as well as a horizontal flow of water through a sloped filter opening. The filter provides treated drinking water to a rural Indian village. The filter has functioned with minimal maintenance for five years without bei...

Escherichia Coli is the ubiquitous microorganism contaminating the drinking water. This study is using granular bed filtration as a vigorous, simple and economical method to prevent the penetration of bacterial contamination, by discovering an alternative filter media from local source namely the burnt oil palm shell (BOPS). The result indicated that dual media BOPS/sand were higher reduction a...

Small particles typical of liquid swine manure often clog sand filter beds and fine filters. We evaluated the effectiveness of polymer flocculants to improve drainage and filtration performance of sand filter beds by increasing the particle size of manure. A pilot separation unit was evaluated at the Swine Unit of the NCSU Lake Wheeler Road Laboratory in Raleigh, North Carolina, in 40 consecuti...

Sand coverings account for a large part of the cost of a project. The purpose of this study is to evaluate the performance of different coatings for filtration of underground drains and reduce the cost of cornfield farms. The experiments were carried out in farm in Salman Farsi. The subsoil drainage was fitted to each test piece with a length of 120 meters, a diameter of 100 mm, and a distance ...

The upper layer formed on the surface of theslow sand filter does not appear to play the most important part in bacteriological purification. The sand filters at Pulta, with a capacity of about 99 million gallons daily, offer an excellent opportunity to study such actions, as it sometimes becomes necessary to rake a running filter when it tends to choke, which rapidly diminishes the rate of fil...

A propeller-wash bead filter (PWBF) and a fluidized sand filter (FSF) on a 28 m recirculating system stocked with tilapia maintained favorablewater quality at five different feed rates, ranging from 0.9 to 4.5 kg feed per day. TAN removal rates ranged up to about 200 g TAN/m of media per day for each of the units. Peak rates of 244 g TAN/m of media per day were observed when the recirculating f...

Experimental researches on adsorptive capacity of activated alumina, silica sand and anthracite coal for phosphorus were conducted. Results showed that performances of three filter media were all in line with Langmuir isotherm, and activated alumina adsorptive performance was much better than silica sand and anthracite coal for phosphorus removal. The adsorptive capacity of activated alumina, s...