Effectiveness of a drinking-water treatment sludge in removing different phosphorus species from aqueous solution
23T15:09:48Z September 2011
Drinking-water treatment sludge (DWTS) produced at water treatment plants is an inescapable by-product and has long been treated as a waste for landfill. In this study, a series of batch adsorption tests were conducted using a wide range of phosphorus (P) species to determine the adsorption capacities of freshly dewatered aluminium salt based DWTS. The adsorption process is highly dependant on the pH of the suspension and is good at low pHs with adsorption capacities in the order of orthophosphate>polyphosphate>organic phosphate when these three P species were simulated according to their level in typical municipal wastewater. At pH 4.0, the adsorption capacity for orthophosphate was 10.2 mg-PO43-/g DWTS, polyphosphate was 7.4 mg-PO43-/g DWTS and organic phosphate was 4.8 mg-PO43-/g DWTS. Subsequently, a continuous flow column test with dewatered Al-based DWTS as filter medium was conducted at a hydraulic loading of 2.79 m3/m2.d and an extremely high P loading of 210.5 PO43-/m2.d. The sludge bed remained stable and removed over 80% P in a 30 day period and the bed did not reach saturation point for over 60 days. This proves the potential of the sludge as a filter material in various forms of P immobilization, thus converting it from a waste to a useful material in pollutant control.
Type of Material
Separation and Purification Technology
Copyright (Published Version)
2006 Elsevier B.V.
Subject – LCSH
Water treatment plant residuals
Phosphorus--Absorption and adsorption
Status of Item
This item is made available under a Creative Commons License