水泥窑协同处置工业废弃物的生命周期评价

以废白土、废催化剂和污染土壤等工业废弃物为研究对象,运用生命周期评价(LCA)方法,对水泥窑协同处置废弃物的环境影响进行评价.通过建立生产过程输入、输出清单,从全球变暖潜值、资源消耗潜值、人体毒性潜值等方面,基于Gabi5.0软件进行建模与计算,对水泥窑常规生产工艺与协同处置工业废弃物工艺产生的环境影响进行比较.结果表明:功能单位(1 t)水泥的生产过程中,常规生产工艺和协同处置工艺的环境影响潜值分别为5.78×10~(-11)和5.61×10~(-11),协同处置工艺使得全生命周期环境影响潜值降低了2.94%;水泥生产过程最主要的环境影响是全球变暖和人体毒性,其中,协同处置工艺下这两种环境影响分别降低了0.80%和1.80%,资源消耗相比常规生产降低了11.1%;从全生命周期看,水泥生产中熟料煅烧阶段对环境的影响最大,协同处置工艺下熟料煅烧阶段的环境影响相比常规生产降低了8.0%.协同处置工艺相比常规生产工艺有更好的环境效益.

Life cycle assessment of co-processing industrial waste in a cement kiln

The environmental impact of co-processing with waste clay, spent catalysts, contaminated soil and other industrial waste in cement kilns were assessed by using life cycle assessment (LCA). A life cycle inventory including input and output processes of cement production was established based on inventory analysis. Gabi5.0 software was used to model and calculate the original data to obtain the corresponding environmental impact potentials, and comparisons were made between conventional and co-processing cement processes on global warming potential, resource depletion potential and human toxicity potential. The results showed that the environmental impact values of conventional and co-processing cement processes for per functional unit of cement production were 5.78×10^-11 and 5.61×10^-11 respectively. Compared with conventional production process, the lifecycle environmental impact potential of co-processing was reduced by a factor of 2.94%; global warming potential and human toxicity potential made the greatest contribution to environmental impacts in cement production, with decreased environmental impact potentials of co-processing by 0.80% and 1.80% respectively and the decreased environmental impact potential of co-processing on resource depletion by 11.1%; from the view of a whole lifecycle of cement production, clinker calcination ranked the first in environmental impacts, with a reduced rate of co-processing of 8.0% in comparison with the conventional production process. Co-processing has a better environmental performance than conventional production.