Role of micronutrients in activated sludge-based biotreatment of industrial effluents

Industrial processes often produce wastewaters that resist biological treat ment owing to the unfamiliarity of some components to biological systems. A vailability of nutrients determines the community structure of the activate d sludge and hence the efficiency of the degradation process. Micronutrient s influence the bacteria involved in waste degradation and also the species diversity within the sludge. The requirements for and toxicity of differen t micronutrients vary according to the nature of the waste and the ecology of the sludge. Adding micronutrients to biological treatment processes is o ne possible approach to upgrading an existing facility in order to deal wit h increasing volumes and strengths of industrial wastewaters and the tighte ning discharge legislation. (C) 1999 Elsevier Science Inc. All rights reser ved.