Direct combustion of waste oil in domestic stove by an internal heat re-circulation atomization technology: Emission and performance analysis

摘要

Direct use of waste oil as fuel to meet the residential energy demands, is very attractive due to its poten-tials to decrease fossil fuel consumption, reduce pollution and increase sustainability. This paper uses a domestic stove with an internal heat re-circulation and self-atomization technology to burn yellow waste cooking oil (WCO-1), brown waste cooking oil (WCO-2) and waste lubricant oil (WLO). Emission factors (EFs), energy efficiency and modified combustion efficiency (MCE) of this combined fuel/stove system were determined under space-heating and cooking modes. The results showed that EFs of CO, PM_(2.5), total 16 PAHs and corresponding toxic equivalent quantity (TEQ) values ranged from 2.18 × 10~3 to 4.90 × 10~3 mg/MJ_(ner), 16.36-69.40 mg/MJ_(net), 2.39-12.93 μg/MJ-(net) and 0.16-0.92 μg of TEQ/MJ_(net). WCO-1 was verified to be the cleanest fuel with the highest energy efficiency (85.3 ± 3.3% and 90.4 ± 2.2%) and lowest emis-sion levels, such as NO (53.75 ± 2.62 and 37.09 ± 5.41 mg/MJ_(net)), NO_2 (82.40 ± 3.96 and 56.87 ± 8.29 mg/ MJ_(net)) and PM_(2.5) (20.94 ± 6.55 and 16.35 ± 5.06 mg/MJ_(net)) compared to WCO-2 and WLO. The estimated total cost of using waste oil for each household in winter was much cheaper than some current available clean energy means, including only USD$ 400 of stove price and USD$ 250/ton of fuel per year. It is a promising candidate choice for replacing low-quality solid fuels in rural China and 2.62 million rural households would achieve environmental and economic benefits if promoting direct combustion of waste oil for daily heating and cooking.