Study On Technique-based Effluent Limitations Determining Method

Discharge permit system is a general international environmental management institution.In recent years, discharge permit institution was regarded as the core of stationary point pollution sources management institution in our country. That would greatly enhance the scientific and refinement degree of point source management. The determination of effluent limitation is an important link of license management, is the basis of stationary point source discharging pollutants, is of great significance for the successful implementation of permit institution. The recent domestic and abroad progress of the technology-based effluent limitations (TBELs) was compared and the weaknesses of research in China was summarized. Considering the experience of the United States and the European Union, the TBELs determining technology method was put foward which was suitbale for the actual situation of water pollution control and management in our country.The paper analyzed the technical support of discharge standards, clean production evaluation index system and best available technology guidelines (BAT guidelines) on the determining TBELs. It pointed out that discharge standards was the main basis of determining pollutant discharge concentration limitation and pollutant load limitation, determining the concentration limitation of pollutants and average daily (24 hours-average) maximum load limitation. Cleaner production evaluation index system and BAT guidelines could provide certain reference on determining load limitation. Combined with cases, the paper provided determining method of maximum daily concentration limitation and maximum daily load limitation under different degree of integrity of three sets of standard (guidelines).Paper proposed methods to calculate different temporal average periods limitations, including maximum daily limitation, maximum weekly limitation and maximum monthly limitation, under different monitoring data integrity. If monitoring datas can meet more than once a week in the frequency, different temporal average periods limitations could be determined by using monitor data analyzing method; if monitoring datas can meet once a month in the frequency, different temporal average periods limitations could be determined by using NPDES providing method. Because results of limitations by the NPDES providing method was in line with results by monitoring data analyzing method through cases study, NPDES providing method in determining limitation was effective. Under the condition of absence of monitoring data, the research could refer to results of calculated βMDL,βAML,βAWL of previous research, and then deduced the results of AWL,AML and LTA.Taking examples for discharge units in Tieling, the paper carried out cases study. Selecting typical enterprise of poultry slaughtering industry and beer production industry, the paper calculated maximum daily concentration limitation, average monthly concentration limitation, maximum annual load limitation and maximum daily load limitation of COD and ammonia nitrogen.