Research On Modification Of Heavy Metal Generation Coefficients Based On Comprehensive Evaluation Index Of Pollutants Generation Intensity

Pollutants generation and discharge coefficients accounting, which is a fundamental instrument for Chinese environmental management, is one of the major accounting methods for survey of pollution sources in China. However, owing to the orientation of coefficients during the development process and target enterprises’own limitations, some problems do exist in current using of coefficients, the most eminent phenomenon of which is the great deviation between accounting numbers and actual generation and discharging intensities, enabling the modification urgent.Compared to other pollutants, pollution of heavy metal, characterized by extensive pollution range, long lasting time, secluded influence, difficult degradation and biological concentration, imposes more threats on social&economic development and human’s health and lives. Accounting and surveillance over generation of heavy metal in key enterprises can promote the improvement of heavy metal management system in China, enhance prevention and control of environmental pollution accidents and elevate environmental and human’s living equality.The paper determines the research objects by literature analysis, then carries out the related research process and acquires the corresponding results as follow:i) Applicability analysis of heavy metal generation coefficients is performed. First, considering connotation and applying scope, the method for applicability analysis of generation and discharging coefficients is structured combined with principles of statistics. The sample data is guaranteed to be normal distribution by goodness of fit, then, T-hypothesis testing is carried out to verify the consistency between pollution generation&discharging coefficients and mean value of sample intensities. Meanwhile, dispersion analysis is performed within every single sample enterprise. Finally, the applicability is concluded.ii) Comprehensive evaluation index system for heavy metal generation intensity is constructed. The principles for screening and discriminating of factors are established, namely principle of relevance, easy accessibility and comprehensiveness during the process of primary factors election; through overall comparison of many nethods for factor discerning, correlation analysis method is chosen as the one for correlative factors of heavy metal production intensity; By Experts Grading Method and Analytic Hierarchy Process (AHP), the main factors which turn out to be correlated to pollution generation intensity are weighted and graded and comprehensive evaluation index system is constructed, from which the comprehensive index is gained.iii) Modified index model for heavy metal generation coefficients is constructed. The heavy metal generation coefficient under certain operation condition is chosen and the modification is based on the fitting of mathematical model between comprehensive index and practical generation intensity of enterprises.iv) Instance analysis is carried out. The lead-acid battery industry is chosen as the typical case and empirical analysis of lead generation coefficient is taken under some specific operation condition, whose result shows that the target generation coefficient is still applicable under current production status, which lays the foundation of modification; An analysis for current main artwork of lead-acid battery manufacturing industry is conducted and major links of pollutants generation are examined, through which eight respective basic factors potentially related to heavy metal (lead) generation in both waste water and gas are discerned; By means of the statistical software SPSS, the paper conducts a correlation analysis between basic factors and practical heavy metal generation intensity of enterprises and main factors related to generation intensity are acquired, including two factors for waste water and7ones for waste gas; Based on which, the comprehensive evaluation systems for lead production intensity within both waste water and gases are respectively built. Finally, modified index model aiming at lead generation coefficient for waste water is acquired.