Lin (Graduate Research Assistant) Department of Civil and Environmental Engineering University of … The CF experiments were conducted using alum as coagulant and polyacrylamide as coagulant aid whereas the PCO tests were carried out using H2O2 in the presence of UV light irradiation. The number of bacteria present in water is also considerably reduced. Coagulation combined with centrifugation improved the removal efficiency of suspended solids (70%). Second, the suspension is slowly stirred to, increase contact between coagulating particles and to, facilitate the development of large flocks. After the addition of, alum and ferric chloride at a concentration of 2, the pH decreased. Colloidal clay particles are generally in the submicron size, i.e. 84 0 obj <> endobj The coagulant dosages ranged from. The effect of alum, ferric chloride and ferrous sulphate as coagulants on the treatment of samples collected from two different discharged streams was studied. Such particles were found to be removed due to adsorption of the colloids. Suspensions. An evaluation of two commonly used coagulation–flocculation aids (alum and ferric chloride) was conducted for the supernatant overflow from settling cones used to treat the effluent from microscreen filters in an intensive recirculating aquaculture system. A liquid dispersed in a gas is referred to as a fog. 14, which shows decrease in turbidity of r, comparison was made on basis of the percentage of, coagulation with aluminum sulphate and ferric chloride, is an effective method to clarify raw water by reducing, the turbidity and will lead to reduce treatment costs for, industries. The analysis comprises the characteristics of Egyptian drainage water and technological requirements to pretreat this wastewater category for subsequent desalting stage. study, the effect of polyaluminum chloride (PACl) coagulant characteristics on dissolved residual aluminum concentrations after coagulation and filtration was investigated. Colloids are very low diameter particles which are responsible for the turbidity or the color of surface water. Survey results suggest that effective removal of particulate matter minimizes residual Al levels, especially when raw water contains elevated concentrations of total Al. These are systems based on separation process using membranes having pore sizes in range of 0.1 to 0.001 micron and provide assistance in removing colloidal materials, high molecular-weight substances as well as organic & inorganic polymeric molecules. The particles of which the colloid is made are called the dispersed material. mixing or through the bridging action of coagulant aids, of a high molecular weight becomes attached at a, number of adsorption sites to the surface of negatively, charged particles along the polymer chain. A high degree of clarification is attained as indicated by an excess of 85–86% colour removal. Tunick and M.A. Teng, A.L. post-treatment of wastewater from the slaughter of pigs, in order to remove the remaining recalcitrant fractions from the The orthophosphate removal efficiency for alum and ferric chloride were greater than 90% at a dosage of 60 mg/L. The combined process of CF and UV/H2O2 may be a useful treatment technique for wastewater contaminated with reactive dyes. This is due to the reason that inadequately treated or untreated industrial wastewater effluents may cause eutrophication in the receiving water bodies and also form a favorable condition for toxin-pro-ducing waterborne pathogens. To remove colloids, small particles have to be destabilized first to form the larger and heavier flocks which can easily be removed by conventional physical … The coagulation process, which is a process of destabilising colloids by reducing the zeta potential to agglomerate the colloids together forming small flocs, is a central part of chemical treatment of water and wastewater, The goal of this work is to investigate the behavior of small droplets under electrical field (di-electriphoresis) using different condition such as different frequency, voltages and different wave, The aim of this study was to evaluate and compare the treatment of petrochemical wastewater with an integrated anaerobic baffled reactor and microbial electrolysis cell (ABR-MEC) and anaerobic baff, Regional Drinking Water Company (PDAM) of County Ogan Komering Ilir has two problematic water treatment units. & Environ. 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