摘要：The local wastewater treatment facility in Yanbu Industrial City receives 24,000 m3/day of industrial wastewater. This wastewater, mostly from refineries and petrochemical industries, goes through physical, biological and chemical stages of treatment. However, the treated water still fails to pass some of the permissible levels set by governmental agencies. This research paper investigated the enhancement of the treatment processes to reduce the turbidity of the effluent treated water. Ferric chloride, ferrous sulfate, alum and commercial synthetic cationic polymer were tried as coagulants. Different conditions (i.e., pH, temperature, dose, stirring rate) were searched. Ferrous sulfate and polymer reduced the final turbidity to acceptable values with very low doses compared with other coagulant.
