Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6.627, Campus Pampulha, Belo Horizonte, MG 31270-901, Brazil E-mail:
Department of Chemistry, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, MG 35400-000, Brazil.
Water Sci Technol. 2020 May;81(9):1951-1960. doi: 10.2166/wst.2020.250.
Two bioreactors were investigated as an alternative for the post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, aiming at dissolved sulfide and methane removal. The bioreactors (R-control and R-air) were operated at different hydraulic retention times (HRT; 6 and 3 h) with or without aeration. Large sulfide and methane removal efficiencies were achieved by the microaerated reactor at HRT of 6 h. At this HRT, sulfide removal efficiencies were equal to 61% and 79%, and methane removal efficiencies were 31% and 55% for R-control and R-air, respectively. At an HRT of 3 h, sulfide removal efficiencies were 22% (R-control) and 33% (R-air) and methane removal did not occur. The complete oxidation of sulfide, with sulfate formation, prevailed in both phases and bioreactors. However, elemental sulfur formation was more predominant at an HRT of 6 h than at an HRT of 3 h. Taken together, the results show that post-treatment improved the anaerobic effluent quality in terms of chemical oxygen demand and solids removal. However, ammoniacal nitrogen was not removed due to either the low concentration of air provided or the absence of microorganisms involved in the nitrogen cycle.
两个生物反应器被研究作为上流式厌氧污泥床（UASB）反应器处理生活污水的出水的后处理替代方法，旨在去除溶解的硫化物和甲烷。生物反应器（R-对照和 R-空气）在不同水力停留时间（HRT；6 和 3 h）下运行，或曝气或不曝气。微曝气反应器在 HRT 为 6 h 时实现了大的硫化物和甲烷去除效率。在该 HRT 下，R-对照和 R-空气的硫化物去除效率分别为 61%和 79%，甲烷去除效率分别为 31%和 55%。在 HRT 为 3 h 时，硫化物去除效率分别为 22%（R-对照）和 33%（R-空气），且甲烷未去除。在两个阶段和生物反应器中，硫化物的完全氧化，伴随着硫酸盐的形成，占主导地位。然而，在 HRT 为 6 h 时，元素硫的形成比在 HRT 为 3 h 时更为主要。综上所述，结果表明，后处理提高了厌氧出水的质量，包括化学需氧量和固体去除。然而，由于提供的空气浓度低或参与氮循环的微生物不存在，氨氮没有被去除。
