Flocculation Performances of Polymers and Nanomaterials for the Treatment of Industrial Wastewaters

Investigation of the Potential of Monomeric and Polymeric Coagulants in the Treatment of Raw Water used at a Coal-Fired Power Station

“…When added to water aluminium and iron salts hydrolyse and form soluble monomers and polymers. The hydrolysed salts bind strongly with the negatively charged suspended solids and promote settling [17,27].…”

“…This requires that the raw water be treated to an acceptable standard. Three major concerns exist when untreated raw water is sent to the plant: corrosion, scaling and biological fouling resulting in Elvis Fosso-Kankeu is with the School of Chemical and Minerals Engineering of the North West University, Bult area-Potchefstroom-South Africa Frans Waanders is with the School of Chemical and Minerals Engineering of the North West University, Bult area-Potchefstroom-South Africa Louise Dreyer is with the School of Chemical and Minerals Engineering of the North West University, Bult area-Potchefstroom-South Africa deterioration of equipment, deposits on equipment and accumulation of microorganisms in the reverse-osmosis membranes and ion-exchange resins [16,17]. The treatment of raw water at Grootvlei Power Station is focused on removing the scale forming agents from the water in an attempt to reduce the damage caused to the RO-membrane in the downstream processes [16].…”

“…Coagulation-flocculation has been the conventional method for over a century to remove suspended solids from raw water, improving the turbidity and colour of water [17]. The mechanism involves the destabilization of suspended solids, by reducing the forces that keep them apart, to form aggregates [17].…”

“…The mechanism involves the destabilization of suspended solids, by reducing the forces that keep them apart, to form aggregates [17]. Aluminium sulphate and ferric chlorides are commonly used inorganic coagulants in the treatment of wastewater and drinking water.…”

“…The suspended solids collide to form larger aggregates, referred to as flocs, which can be separated from the water [3, 19 -25]. Flocculation will follow coagulation, as the suspended solids form particles large enough to promote adequate settling of the suspended solids [17,26]. The flocculation mechanism must be effective to the extent that the flocs formed settle out at a satisfactory settling velocity after which the settled particles can be separated from the water in a clarifier.…”