Real-time emission and stage-dependent emission factors/ratios of specific volatile organic compounds from residential biomass combustion in China

• Published in: Atmospheric research 2021-01, Vol.248, p.105189, Article 105189
• Main Authors: Zhang, Ying, Kong, Shaofei, Sheng, Jiujiang, Zhao, Delong, Ding, Deping, Yao, Liquan, Zheng, Huang, Wu, Jian, Cheng, Yi, Yan, Qin, Niu, Zhenzhen, Zheng, Shurui, Wu, Fangqi, Yan, Yingying, Liu, Dantong, Qi, Shihua
• Format: Article
• Language: English
• Subjects: 11 sorts of bio-fuels combustion; Emission factors; PTR-TOF-MS; Real time emission; Volatile organic compounds
• ISSN: 0169-8095; 1873-2895
• DOI: 10.1016/j.atmosres.2020.105189

The absence of emission factors (EFs) with high-time resolution primarily hinders developing high time-resolution emission inventory for air pollutants, which further restricted the accuracy of air quality modeling, especially for a pollution process. The real-time emission concentration of volatile organic compounds (VOCs) in the combustion process of eleven kinds of residential biomass fuels (RBFs) were studied using a high-resolution proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS). The dynamic EFs for 18 types of VOCs were firstly obtained with the records of fuel consuming amounts by a balance of high precision. The RBFs burning lasted for about 3–15 min for each experiment with 53–130 g fuels burned. The VOCs concentrations of biomass combustion varied in 0–10 ppm, and exhibited single peak values at about 1–4 min for the entire burning processes. Aldoketones accounted for the largest proportion of the 18 types of VOCs (46.6%–53.6%), followed by methanol (29.2%–44.6%) and alkene (26.2%–31.7%). The real-time EFs of VOCs from RBFs burning firstly decreased to the lowest value of 0.001–3.84 mg/g, and then increased to about 0.23–148 mg/g until the end of combustion processes. The VOCs EFs of all biomass combustion in flaming (1.65 ± 1.55 mg/g) were lower than those in smoldering (16.0 ± 11.3 mg/g). The benzene to toluene (B/T) ratios peaked at 100–200 s of biomass burning processes and changed in 0.07–4.06 for different burning stages. It should be noted that isoprene which was always regarded as the marker for VOCs emitted from biogenic evaporation, can also be released from biomass fuels burning, with real time EFs of 3.16 ± 5.16 mg/g. Its emission amounts and relative importance from combustion sources should be assessed. The high time-resolution of VOCs emission concentrations, emission factors and specific species ratios provide new datasets. They would be useful for dynamic source apportionment and developing high-time resolution emission inventory of VOCs. [Display omitted] •The real-time emission of VOCs from RBFs combustion exhibited a single peak distribution.•The real-time EFs of 18 VOCs from 11 kinds of biomass combustion were obtained.•VOCs EFs from RBFs during smoldering were 5–30 times higher than those during flaming.•The B/T ratios of biomass burning changed in 0.07–4.06 for different burning processes.