Pollution source apportionment and health risk assessment of VOCs in automobile gearbox remanufacturing facilities

The progress of the transmission remanufacturing industry is in line with the development requirements of the circular economy, but its environmental pollution problems are easily ignored. This study conducted an analysis of pollutant sources and health risks associated with VOCs in gearbox remanufacturing plants. A method for prioritising air pollution control based on health risks and environmental impacts, alongside offering suggestions for VOC prevention and control from an environmental standpoint is established. Using the Positive Definite Matrix Factor (PMF) model, pollutant source analysis of VOCs in the plant identified five primary sources of pollution: waste transmission lubricant, carburetor cleaner, rust remover, ultrasonic cleaning water, and new transmission lubricant. Health risk evaluation revealed that the carcinogenic risk of VOCs in seven key process areas exceeds acceptable thresholds. It was observed that areas such as the disintegration area, case cleaning area, and parts inspection area pose higher carcinogenic risks, and benzene, ethylbenzene, 1,2-dichloroethane, and trichloromethane were identified as key contributors. Except for the staging area and parts cleaning area, the processes' locations pose noncarcinogenic health risks to humans, with the sandblasting area showing the highest risk, primarily due to toluene and methylene chloride. Furthermore, a screening method identified ten priority VOCs for control in remanufacturing plants, including methylene chloride, carbon tetrachloride, toluene, and ethylbenzene. These findings will contribute to the understanding of VOC pollution in gearbox remanufacturing plants, assisting the industry in implementing pollutant control measures and achieving cleaner production.