基于农副食品加工行业生产特性的排放限值核定方法研究

与传统的简单以行业排放标准、环评报告、国家分配的目标总量等为依据的排污许可限值核定方式不同，本研究从农副食品加工行业产量、废水排放等生产特性出发，筛选控制项目，确定多级许可限值，运用直接数据分析法、间接数据分析法、假设推导法，制定基于不同时间尺度的最大日排放浓度限值（C_MDL）、月平均排放浓度限值（C_AML）、日最大负荷限值（MDL）、月平均负荷限值（AML），并以河南省某屠宰及肉类加工企业为例，进行基于生产特性的排污许可限值计算示范.结果显示：该企业产量随季节变化率超过20%，氨氮排放量波动明显；制定多级排放限值，COD、总氮和总磷无明显变化，制定统一限值，计算结果均严于传统方法核算的排放限值；在此基础上制定的排放限值，可在有效约束企业排污的同时，为排污许可制度的精细化、差异化管理提供技术支持.

Approved emission limits based on production characteristics of agricultural and sideline food processing industries

The traditional approach of pollutant discharge permit limit verification is based on industrial discharge standard, environmental impact assessment report, national total discharge control target, etc.Replacing, the pollutant discharge permit limit of a case study in a slaughtering and meat processing enterprise in Henan Province was calculated basing on production characteristics. The control items were screened and the multi-level permission limits were determined on the basis of the production characteristics of agricultural and sideline food processing industry (output, wastewater discharge, etc.). The maximum daily load of concentration (CMDL), average monthly load of concentration (CAML), maximum daily load (MDL) and average monthly load (AML) were established as well based on different time scales by using direct data analysis, indirect data analysis and hypothetical deduction methods. Results showed that the seasonal variation rate of the output of the enterprise reached over 20%, with obvious fluctuation in ammonia nitrogen discharge. There was no significant change in the discharges of COD, total nitrogen and total phosphorus under the establishment of multi-level discharge limits. With the formulation of unified limit values, corresponding calculation results were all stricter than the discharge limit values calculated by traditional method. Collectively, the discharge limit established on this basis can not only effectively restrict the pollutant discharge of enterprises, but also provide technical support for refined and differentiated management of pollutant discharge permit system.