Department of Civil Engineering, Inha University, 100 Inharo, Nam-gu, Incheon, 22212, Republic of Korea.
Department of Environmental Engineering, Chungbuk National University, 1 Chungdae-ro, Seowon-Gu, Cheongju, Chungbuk, 28644, Republic of Korea.
Water Res. 2019 Apr 1;152:234-240. doi: 10.1016/j.watres.2019.01.005. Epub 2019 Jan 16.
In addition to undesirable odorous gases, substantial amounts of greenhouse gases (GHG), particularly methane (CH), are generated during the storage of livestock manure. To reduce the CH emissions, first, pig slurry (PS) was stored for 40 d at 30 °C after adjusting the pH at 5.0-7.0 using HSO solution. In the control (non-acidified PS), 3.7 kg CO eq./ton PS of CH emissions was detected, which was reduced to 1.8, 0.9, 0.4, 0.2, and 0.1 kg CO eq./ton PS at pH 7.0, 6.5, 6.0, 5.5, and 5.0, respectively. Methanosarcina was found to be the dominant genus (67% of the total archaeal sequence) in the control, whose dominance was reduced as storage pH decreased. The results of ribonucleic acid analysis and specific methanogenic activity test further confirmed the inhibition of indigenous methanogens by acidification. Later, the biochemical CH potential of stored PS was tested. Compared to the control (10.6 L CH/L PS), the acidified PS showed higher CH yields of 12.7-14.6 L CH/L PS, presumably by keeping degradable organic matters in PS under acidic condition. Among different acidification pHs tested, the maximum amount of GHG reduction was achieved at pH 6.0 by reducing CH emission to +0.4 kg CO eq./ton PS during storage while increasing biogas production potential equivalent to 48.3 kWh/ton PS (-22.5 kg CO eq./ton PS), resulting in a further reduction of (-)9.6 kg CO eq./ton PS compared to the control.
除了不良气味气体外，大量的温室气体（GHG），特别是甲烷（CH），在储存家畜粪便时会产生。为了减少 CH 排放，首先，将猪粪（PS）在 30°C 下储存 40 天，并用 HSO 溶液将 pH 值调节至 5.0-7.0。在对照（未酸化 PS）中，检测到 3.7kg CO eq./吨 PS 的 CH 排放量，当 pH 值分别为 7.0、6.5、6.0、5.5 和 5.0 时，排放量分别降低至 1.8、0.9、0.4、0.2 和 0.1kg CO eq./吨 PS。在对照中，Methanosarcina 是优势属（总古菌序列的 67%），随着储存 pH 值的降低，其优势度降低。核糖核酸分析和特定产甲烷活性测试的结果进一步证实了酸化对土著产甲烷菌的抑制作用。后来，测试了储存 PS 的生化 CH 潜力。与对照（10.6L CH/L PS）相比，酸化 PS 显示出更高的 CH 产量 12.7-14.6L CH/L PS，这可能是因为在酸性条件下保持了 PS 中的可降解有机物。在测试的不同酸化 pH 值中，通过在储存过程中使 CH 排放减少到+0.4kg CO eq./吨 PS，同时增加相当于 48.3kWh/吨 PS 的沼气产生潜力（-22.5kg CO eq./吨 PS），在 pH 值为 6.0 时实现了最大的 GHG 减排量，与对照相比，进一步减少了（-）9.6kg CO eq./吨 PS。
