Sludge wastewater treatment system problems

Problems of an Existing Activated Sludge Wastewater Treatment System... 

The discharge from both domestic and industrial wastewater treatment plants (for example, from activated sludge processes) has been a low-cost source of makeup for cooling systems for many years. Efforts to reuse water continue to gain momentum for environmental conservancy and economic reasons, but the fact that secondary use waters are, by definition, of a lower grade than other supply sources inevitably means an increased risk of deposition or fouling problems in the cooling system. 

The Control of Industrial Pollution Water Quality and Health Aspects of the Chemistry and Analysis of Substances of Concern in the Water Cycle The Role of Wastewater Treatment Processes in the Removal of Toxic Pollutants Sewage and Sewage Sludge Treatment The Chemistry of Metal Pollutants in Water Effects of Pollutants on the Aquatic Environment Important Air Pollutants and Their Chemical Analysis Pollutant Pathways and Modelling of Air Pollution Legislation and the Control of Air Pollution Catalyst Systems for Emission Control from Motor Vehicles Evaluating Pollution Effects on Plant Productivity A Cautionary Tale Epidemics of Non-infectious Disease Systems Methods in the Evaluation of Environmental Pollution Problems Organometallic Compounds in the Environment. 

The heavy metals present in refinery effluents (As, Cd, Cr, Co, Cu, Fe, Pb, Ni, and Zn) are generally in such low concentrations that they do not pose serious problems for conventional treatment methods. If heavy metals reduction should be required by effluent guidelines, provisions should be made for their removal before discharging to municipal systems. The biological sludge developed from refinery wastewaters can be thickened and dewatered by conventional methods such as vacuum filters and centrifugation. 

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