镍闪速炉熔炼共生产品生命周期评价碳排放分配问题

Allocation of GWP Emission for the Co-products of the Flash-smelting Process of Nickel

金属镍生产是典型的多元素共生冶炼过程,清单分配问题是制约其生命周期评价准确性的重要技术因素。以共生反应最为密集的硫化镍矿闪速炉熔炼流程为研究对象,采取边界扩展、物理关联、质量分配等多种清单分配方法,在Ni、Cu、S这3种元素之间进行CO_2排放分配。边界扩展分配计算结果显示,非金属共生元素与金属产物之间的分配结果为29.86%,金属共生元素之间的分配结果为70.14%。对比分析结果显示,边界扩展方法对于中间态产物的适用性较差;物理关联分配结果准确,但需要大量流程工艺参数支撑;质量分配易于计算,但其准确性取决于共生产品之间的物理化学属性差异。

Nickel production is a typical multi-element symbiotic smelting process,and inventory allocation is an important technical factor that restricts the accuracy of its life cycle assessment.In this study,the flash furnace smelting process of nickel sulfide ore with the most intensive symbiotic reaction was taken as the research object,and various inventory allocation methods such as system boundary extension,physical relationship and mass allocation were adopted to allocate CO_(2) emissions among the three elements of Ni,Cu and S.The allocation calculation results by system boundary extension show that the allocation factor of non-metallic symbiotic elements is 29.86%,and the allocation factor of metal symbiotic elements is 70.14%.The results show that the system boundary extension method is not suitable for intermediate products.The factor of physical relationship allocation are accurate,but need to be supported by a large number of process parameters.The mass allocation is easy to calculate,however,its accuracy depends on the differences of physical and chemical properties between symbiotic products.