Evaluation of biological technologies for wastewater treatment in the pharmaceutical industry

Abstract

Wastewater from a pharmaceutical and chemical company provides the material of this study. The company produces drugs, diuretics, laboratory chemicals and others. The company is located 30 km north of Cairo, and discharges both industrial (1050 m3/d) and human wastewater (8400 m3/d) without treatment into a near-by evaporation pond. Reduction of pollutants in the wastewater down to permissible concentrations is necessary for the protection of ground water and the environment. Analysis of the combined wastes indicated that it is very acidic and contains high concentrations of organic compounds and total solids. Combined wastes were subjected to different treatment processes for final disposal into surface water, or reuse for irrigation purposes. Biological treatment of the combined wastes was carried out using both batch and continuous flow systems. The biological treatments included activated sludge process, fixed film reactor, and fixed film reactor followed by activated sludge process. Technical feasibility studies indicated that good quality effluent could be obtained using either extended aeration (20 hr aeration) or a fixed film reactor followed by activated sludge (11 hr detention time). Residual BOD5, COD, oil and grease concentrations in the treated effluent were complying with the National Regularity Standards. When constructional cost was considered, extended aeration was the first choice. Engineering designs of the proposed treatment options are included.