Comparative life cycle assessment of remanufacturing cleaning technologies

Remanufacturing cleaning is an essential but high polluting process in remanufacturing. The novel remanufacturing technologies like supercritical CO2 cleaning and liquid blasting cleaning are under development and possibly tend to substitute the conventional ones like high temperature decomposition and shot blasting. Therefore, it is necessary to demonstrate whether these newly emerged cleaning methods have the environmental superiority and to figure out hotspots for environmental performance promotion. The present study conducted a life cycle assessment (LCA) application on comparing these two types of cleaning technologies from the perspective of environment. Environmental impacts of supercritical CO2 cleaning system using electricity from different power grids and high temperature decomposition cleaning system consuming different fuel mix are quantified separately. The results indicate that the novel cleaning technologies are environmental friendly compared with conventional ones. High temperature decomposition has the largest comprehensive environmental impact, followed by supercritical CO2 cleaning, shot blasting, and liquid blasting cleaning. In addition, electricity and diesel (or natural gas) consumption are the main environmental loads contributors of supercritical CO2 cleaning system and high temperature decomposition system, respectively. Furthermore, supercritical CO2 cleaning is more environmentally favorable when using the electricity from central and southern power grid. And comprehensive environmental impact of high temperature decomposition decreases with the increasing percentage of natural gas in the fuel mix.