Life Cycle Analysis of Greenhouse Gas and PM2.5 Emissions from Restaurant Waste Oil Used for Biodiesel Production in China

Waste cooking oil (WCO) can serve as a feedstock for producing biodiesel, which would not only address food security and waste disposal but also has the potential to reduce emissions of greenhouse gas (GHG) and particulate matter of 2.5 μm or smaller (PM2.5). In this study, we assessed restaurant waste oil (RWO) availability in China and conducted life cycle analysis (LCA) of GHG and PM2.5 emissions of RWO-based biodiesel using the GREET model. The results showed that the amount of RWO in China varies between 0.56 and 1.67 million tons in 2013 and between 0.54 and 1.63 million tons in 2014. Life cycle analysis estimated reduction of GHG and PM2.5 emissions through the use of RWO-based rather than petroleum-based biodiesel of 82 kg CO2-Eq. (90 %) and 0.92 g PM2.5 (46 %) respectively per 100 km driven by busses in 2014 in Shanghai, China. Given the total amount of RWO available in 2014 in China, the potential mitigated annual GHG emission ranges, in China, are 1.51 ∼ 4.52 × 106 tons of CO2-eq and 16.94 ∼ 50.83 tons of PM2.5.