Global Omnium Medioambiente, S.L., Gran Via Marqués del Túria 19, 46005 València, Spain.
Global Omnium Medioambiente, S.L., Gran Via Marqués del Túria 19, 46005 València, Spain.
J Hazard Mater. 2022 Oct 5;439:129641. doi: 10.1016/j.jhazmat.2022.129641. Epub 2022 Jul 20.
Nitrification of centrate from anaerobic sewage sludge digestion presents a major opportunity as an electron acceptor in anoxic biogas biodesulphurisation. Nitritation and nitrification inhibition by free ammonia was detected at laboratory scale, but was avoided during the scale-up operation in a 4 m reactor treating ammonium loads up to 19 gN m h. This nitrate-rich stream was fed to two pilot-scale suspended biomass bioreactors (SBBs) treating real biogas for 220 days. After an adaptation period of 21 days, nitrate and alkalinity concentrations in the liquid medium below 10 mgN L and 100 mgCaCO L were found to limit hydrogen sulphide (HS) oxidation. Once controlled, 95% of the HS was removed in SBB1 and 90% in SBB2, at a gas residence time (GRT) of 5.9 min, treating average values of 321 ± 205 ppmv and 457 ± 205 ppmv, respectively. Outlet HS concentrations of 16 ± 24 ppmv in SBB1 and 46 ± 39 ppmv in SBB2 were obtained, which are below the requirements of biogas combustion heat and power engines. Unlike HS, siloxanes were not removed with these GRTs. The results demonstrate the feasibility of the combined process for HS treatment, potential valorisation of precipitated elemental sulphur and a reduction in the reagents currently used to control HS.
厌氧消化剩余污泥浓缩液中的硝化作用是缺氧沼气生物脱硫工艺中作为电子受体的主要机会。在实验室规模下检测到游离氨对亚硝化和硝化的抑制作用，但在 4 m 反应器的放大运行中，游离氨被避免了，该反应器处理的氨氮负荷高达 19 gN m h。这种富含硝酸盐的水流被输送到两个中试规模的悬浮生物质生物反应器（SBB）中，用于处理实际的沼气，运行时间为 220 天。经过 21 天的适应期，发现在液体介质中硝酸盐和碱度浓度低于 10 mgN L 和 100 mgCaCO L 时会限制硫化氢（HS）的氧化。一旦得到控制，在 SBB1 和 SBB2 中分别有 95%和 90%的 HS 在 5.9 min 的气体停留时间（GRT）下被去除，分别处理 321±205 ppmv 和 457±205 ppmv 的平均浓度。在 SBB1 和 SBB2 中，出口 HS 浓度分别为 16±24 ppmv 和 46±39 ppmv，低于沼气燃烧热和动力发动机的要求。与 HS 不同，硅氧烷在这些 GRT 下没有被去除。结果表明，该联合工艺用于 HS 处理、沉淀的元素硫的潜在增值以及减少目前用于控制 HS 的试剂是可行的。
