State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
School of Management Science and Engineering, Nanjing University of Information Science and Technology, Nanjing, 210044, PR China.
Environ Pollut. 2022 Feb 15;295:118648. doi: 10.1016/j.envpol.2021.118648. Epub 2021 Dec 7.
Estimations of greenhouse gas (GHG) emissions from municipal wastewater treatment plants (MWTPs) remain significant uncertainties in China owing to a lack of reliable emission factors (EFs). This study developed a framework to obtain multi-level (technology, province, and nation) GHG EFs of MWTPs using a database containing 3107 MWTPs in China and published site-specific monitoring data. Results show that GHG EFs of different technologies range widely from 180.0 to 615.7 g CO-eq/t wastewater, and significant differences are also observed among different provinces in China (190.5-600.3 g CO-eq/t wastewater), which are generally lower than the previous estimates. It confirms the importance of more detailed technology classification and considering the technological disparity of different provinces in refining GHG estimations of MWTPs. To test the feasibility of the developed EFs, we compared GHG emissions from MWTPs based on multi-level EFs at different spatial and temporal scales. Similar estimation results imply that selecting corresponding EF depending on the availability of activity data would simplify GHG estimations of MWTPs without sacrificing much accuracy. This study contributes a set of well-developed EFs to improve the estimates of GHG emissions from MWTPs, and also offers a method to develop GHG EFs for other sectors.
由于缺乏可靠的排放因子 (EF)，中国城市污水处理厂 (MWTP) 的温室气体 (GHG) 排放量估算仍然存在很大的不确定性。本研究开发了一个框架，使用包含中国 3107 个 MWTP 的数据库和已发表的特定地点监测数据，获得 MWTP 的多层次 (技术、省份和国家) GHG EF。结果表明，不同技术的 GHG EF 范围很广，从 180.0 到 615.7 g CO-eq/t 废水不等，中国不同省份之间也存在显著差异 (190.5-600.3 g CO-eq/t 废水)，通常低于以前的估计。这证实了在细化 MWTP 的 GHG 估算时，更详细的技术分类和考虑不同省份的技术差异的重要性。为了测试所开发的 EF 的可行性，我们比较了基于不同空间和时间尺度多层次 EF 的 MWTP 的 GHG 排放。相似的估算结果表明，根据活动数据的可用性选择相应的 EF 将简化 MWTP 的 GHG 估算，而不会牺牲太多的准确性。本研究提供了一套经过充分开发的 EF，以提高对 MWTP 的 GHG 排放量的估算，并为其他部门开发 GHG EF 提供了一种方法。
