slow sand filters are as a proper technology for pre-treatment of raw water, with a fine and medium trubidity in small communities in developing countries. thus, with a minimum operation cost and minimum need for expest bodies have the maximum efficiency. the purpose of this research is carried out to evaluate the efficiency of two processes of horizontal flow roughing filter and vertical flow ...

High levels of turbidity and suspended solids are the major disadvantages of aerated lagoons. Aerated lagoon effluent filtration was investigated by Horizontal Roughing Filter (HRF). Removal efficiencies were determined by examining total phosphorus (TP) and total Kjeldahl Nitrogen (TKN) from HRF influent and effluent, simultaneously. HRF pilot system located on effluent pump station of Qom was...

high levels of turbidity and suspended solids are the major disadvantages of aerated lagoons. aerated lagoon effluent filtration was investigated by horizontal roughing filter (hrf). removal efficiencies were determined by examining total phosphorus (tp) and total kjeldahl nitrogen (tkn) from hrf influent and effluent, simultaneously. hrf pilot system located on effluent pump station of qom was...

slow sand filtration (s.s.f) is a main process in the water treatment technology and generally considered as most appropriate for application in rural and small urban areas in developing countries. however, performance of the s.s.f is very sensitive to high turbidity levels. therefore, pretreatment is necessary for such waters. horizontal - flow roughing filtration (hfrf) and direct horizontal ...

background: the effective size of the end grain of horizontal roughing filters (hrfs) is larger than 2 mm. this study aimed to examine the efficiency of hrfs in removing nitrate, phosphate, and chemical oxygen demand (cod) from effluent of a wastewater stabilization pond. methods: this experimental study was conducted in 2013. the pilot project was transferred to the karaj wastewater treatment ...

A study on a pilot plant accomplishing synchronous municipal sewerage-sludge stabilization was conducted at a municipal sewerage treatment plant. Stabilization of sewerage and sludge is achieved in three-step process: anaerobic reactor, roughing filter and a microbial-earthworm-ecofilter. The integrated ecofilter utilizes an artificial ecosystem to degrade and stabilize the sewerage and sludge....

A new spiral cutting method and its implementation within a CAD/CAM application software is proposed to save more than 16% in the roughing process of pockets for light alloy aerospace parts. The application prototype developed automatically generates the tool paths related to specific pocket profile geometry. It is shown, through experimentation using the prototype, that the parameters which de...