Life Cycle Environmental Assessment of Three Excavated Soil and Rock (ESR) Treatment Methods: A Case Study in Shenzhen City

Abstract

This study aimed to quantitatively assess the environmental impacts of different methods used for treating excavated soil and rock (ESR) in Shenzhen, namely landfilling, sintering, and non-sintering, using the life cycle assessment (LCA) method. The findings indicate that recycling ESR through sintering or non-sintering processes offers more sustainable alternatives than landfilling. The recycled products derived from ESR can effectively replace traditional building materials, thereby reducing their environmental impacts. However, when comparing the environmental impacts of sintering and non-sintering processes, the latter demonstrated more significant impacts, particularly in terms of global warming potential (GWP), acidification potential (AP), and eutrophication potential (EP). Furthermore, it is worth noting that the environmental impacts of the sintering processes are influenced by fuel type and exhaust gas emissions, with natural gas combustion yielding more substantial overall environmental benefits. Moreover, ESR landfilling poses constraints on sustainable development and land resource occupation. This study contributes to a better understanding of the environmental impacts associated with ESR landfilling and recycling, provides management departments with optimal ESR management suggestions, and alleviates environmental pressure from urban development.