Abstract:
In order to quantitatively assess the environmental impact of contaminated soil remediation projects, the environmental footprint, relative contribution and main sources of each stage of different remediation projects were calculated based on the actual remediation effect of in-situ thermal desorption and barrier ventilation of organic contaminated soil at a northern coking plant, and the environmental footprint intensity of in-situ thermal desorption and barrier ventilation were analyzed. The results showed that the environmental footprint of the remediation project was only about 1% due to the short construction preparation stage and low energy and material consumption; the percentages of energy consumption, water consumption, GHG emission and air pollutant emission for in-situ thermal desorption construction in the high-risk area were 93.02%, 72.82%, 63.39% and 71.08%, respectively; the percentages of energy consumption, water consumption, GHG emission and air pollutant emission for barrier ventilation in the low-risk area were The percentages of energy consumption, water consumption, GHG emissions, and air pollutant emissions in the low-risk area were 6.77%, 26.26%, 35.40%, and 27.74%, respectively. Comprehensively, it seems that the in-situ thermal desorption link brings a larger energy input, among which natural gas use, electrical energy consumption, and fuel for on-site mechanical equipment are the main sources of the environmental footprint of the remediation process at this site; the environmental footprint intensity of benzene is higher than that of benzo(a)pyrene for the thermal desorption remediation project in the high-risk area; the energy intensity of in-situ thermal desorption is higher when analyzed from different remediation technologies; the environmental footprint intensity based on concentration reduction is important for quantifying The environmental footprint intensity based on concentration reduction is better for quantifying the environmental footprint of thermal desorption technology, while the environmental footprint intensity based on risk reduction is applicable to in situ barrier technology. This study's environmental footprint analysis based on actual restoration effects can provide support for mastering the environmental impacts of restoration project implementation and promoting green and sustainable restoration.