Roth Liselott, Eklund Mats
Division of Environmental Technique and Management, Department of Physics and Measurement Technology, Linköping University, SE-581 83 Linköping, Sweden.
Waste Manag. 2003;23(2):107-16. doi: 10.1016/S0956-053X(02)00052-1.
Reuse of by-products in road construction is most often environmentally evaluated from the narrow perspective of the material itself, i.e. the material level. In this article, we argue that the current mainstream environmental evaluation of reuse of by-products in road construction should use wider system boundaries. In order to illustrate the importance of system boundaries to the final result, three additional levels that complement the material level, are applied to the environmental evaluation of reuse of by-products. In total these four levels of evaluation are, firstly, the material itself, mainly studied by leaching tests, secondly, the road environment studied by substance flow analysis, furthermore, a narrow life-cycle perspective and, finally, the industrial system level that addresses the reuse of by-products in a broader sense. Methods and tools applied to different levels emphasise different environmental aspects and consequently they are appropriate for addressing different questions. However, especially for the evaluation of environmental aspects on the industrial system level, there is a need to develop the methods. To apply these four levels to the evaluation would broaden the knowledge about the environmental impacts of the reuse of by-products. We argue that current leaching tests have to be complemented by the broader system boundaries used in substance flow studies and in life-cycle assessments in order to discuss the use of resources and environmental impacts from a wider perspective.
道路建设中副产品的再利用通常从材料本身这一狭义角度进行环境评估，即材料层面。在本文中，我们认为当前道路建设中副产品再利用的主流环境评估应采用更宽泛的系统边界。为了说明系统边界对最终结果的重要性，在副产品再利用的环境评估中增加了三个补充材料层面的层面。这四个评估层面总共包括：首先是材料本身，主要通过浸出试验进行研究；其次是通过物质流分析研究的道路环境；再者是狭义的生命周期视角；最后是从更广泛意义上处理副产品再利用的工业系统层面。应用于不同层面的方法和工具强调不同的环境方面，因此它们适用于解决不同的问题。然而，特别是对于工业系统层面的环境方面评估，有必要开发相关方法。将这四个层面应用于评估将拓宽对副产品再利用环境影响的认识。我们认为，当前的浸出试验必须辅以物质流研究和生命周期评估中使用的更宽泛系统边界，以便从更广泛的角度讨论资源利用和环境影响。
