Prechlorination is used as an initial step in water purification for public supply. One of the drawbacks of the prechlorination is the reaction between natural organic matters with chlorine forming trihalmethanes. This study aims at evaluating the performance of granular activated carbon (GAC) with sand as a dual filtering media with different depths on removal of trihalomethanes (THMs) for imp...

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...

abstract in order to investigate the removal of copper, nickel, zinc and chromium from industrial waste water by a sand–soil–organic matter filter column, this experiment was conducted at a completely randomized design with sixteen treatments and four replications. p.v.c tubes (columns) with 66.5 cm height and 10 cm diameter were chosen and filled from down to top by coarse gravel (15 cm), sand...

Moving bed biofilm reactor (MBBR) is a process in which attached growth is utilized for wastewater treatment. This process does not require sludge recycling or backwash. Activated sludge processes can be promoted to an MBBR by adding media to an aeration tank. Rapid sand filter is a physical method for the removal of total suspended solids (TSS) in advanced wastewater treatment. The purpose of ...

Several innovative filtration technologies have been developed in the last two decades to decrease the backwash requirements, to increase the water production efficiency, and to improve the operational and design conditions. The Compressible Medium Filter (CMF) also known as the “Fuzzy Filter” involves the use of a synthetic compressible fiber (polyvaniladene) porous material as the filtering m...

one of the main problems in micro irrigation system is inappropriate combination and in some cases inappropriate performance of filters and sand tanks in central control systems which cause reduction in efficiency of system and increasing of operating costs. this study evaluates affect the amount of algae on the performance of disc filters sand tank in research farm deputy of soil and water and...

While sand filters are widely used to treat drinking water, the role of sand filter associated microorganisms in water purification has not been extensively studied. In the current investigation, we integrated molecular (based on metagenomic) and physicochemical analyses to elucidate microbial community composition and function in a common sand filter used to treat groundwater for potable consu...

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 ...

Swash zone sheet flow and suspended sediment transport rates are estimated on a 14 coarse sand beach constructed in a large-scale laboratory wave flume. Three test cases under 15 monochromatic waves with wave heights of 0.74 m and wave periods of 8 and 12.2 s were 16 analyzed. Sediment flux in the sheet flow layer exceeds several hundred kg m s during both 17 uprush and backwash. Suspended sedi...

Osmotic backwash experiments were conducted and analytical model was developed in attempt to describe the backwash mechanism. A single unit of a spiral wound RO membrane was used in the experiments. The RO membrane was fed by salted water solution. Permeate flux characteristics of the membrane were determined through steadystate RO experiments. Then the system was shiRed immediately to a backwa...