Concepts and methodologies to minimize pollutant discharge for zero-emission production

The present study aims to present basic concepts to minimize the emissions from industrial production processes. Strategies and methodologies to analyze emissions from various production processes, to establish a so called negative flow sheet and to reduce the emissions from those processes by refining and/or replacing the present production process with an alternative process are discussed. Preliminary evaluation and management systems of the materials used in the production process based on characteristics such as microbial and physico-chemical treatabilities are proposed as well. The relationship between the removal efficiency of dissolved organic carbon in the five-days BOD test and that in a laboratory scale submerged biofilter with continuous operation is suggested to evaluate the biological removability of organic pollutants contained in wastewater. A novel concept to select the appropriate treatment process of an industrial wastewater based on properties such as the molecular size and biodegradability of the pollutants contained in that wastewater is also proposed. To give basic information for the minimization of energy consumption in wastewater treatment, various biological wastewater treatment processes are compared from the view point of power economy.