Biological Processes Laboratory, Center for Research, Development and Innovation in Environmental Engineering, São Carlos School of Engineering (EESC), University of São Paulo (USP), Block 4-F, 1100 João Dagnone Avenue, Santa Angelina, São Carlos, SP, Brazil E-mail:
Biopolymer Technology Laboratory, Faculty of Animal Science and Food Engineering (FZEA), University of São Paulo (USP), Pirassununga, SP, Brazil.
Water Sci Technol. 2022 Mar;85(5):1538-1548. doi: 10.2166/wst.2022.028.
Methane is a powerful greenhouse gas and a source of energy. Recovering this gas means lower greenhouse gas emission and potential reduction of energetic costs. The lack of full-scale results, the use of different methodologies to detect dissolved methane (d-CH) and the fact that no process to remove d-CH from anaerobic effluents is energetically or economically viable at full-scale urged a different approach to the problem. To avoid methodological interference and facilitate comparison of results the Standard Test Method number D8028-17 published by ASTM International can be used to determine d-CH. The use of real anaerobic reactor effluent also helps results to be compared. In this study, 80 samples from a full-scale anaerobic reactor showed an average concentration of dissolved methane of 14.9 mg·L, meaning an emission of 229 kg of CO eq·h and an average of 113.5 kW wasted. Using spray nozzles, an alternative to the methods being researched, the average methane recovery was 11.5 mg·L of CH, an efficiency of 81.6%, meaning 177 kg of CO eq·h emissions avoided and 87.9 kW of recoverable energy.
甲烷是一种强大的温室气体和能源。回收这种气体意味着减少温室气体排放和潜在的能源成本降低。缺乏全面的结果，使用不同的方法来检测溶解甲烷（d-CH），以及从厌氧废水中去除 d-CH 的工艺在全面实施时在能量或经济上都不可行，这促使我们采用了不同的方法来解决这个问题。为了避免方法学干扰，并便于比较结果，可以使用 ASTM 国际发布的标准测试方法编号 D8028-17 来确定 d-CH。使用实际的厌氧反应器流出物也有助于比较结果。在这项研究中，来自一个全规模厌氧反应器的 80 个样本显示溶解甲烷的平均浓度为 14.9 mg·L，这意味着排放了 229 kg 的 CO eq·h 和平均 113.5 kW 的浪费能量。使用喷雾喷嘴，这是对正在研究的方法的一种替代方法，甲烷的平均回收率为 11.5 mg·L 的 CH，效率为 81.6%，这意味着避免了 177 kg 的 CO eq·h 排放和 87.9 kW 的可回收能源。
