Abstract Chemical additives of magnesium chloride (MaC) and ferrous sulfate (FS) were investigated in sewage sludge composting. A treatment without chemical additive was used as the control group (CK). The effects of MaC and FS on ammonia (NH3) and greenhouse gases (CO2, N2O and CH4) emissions were evaluated. The results showed that the addition of MaC and FS promoted the degradation of organic matter and increased the ammonium concentration of the compost product. The maximum pH values decreased from 8.98 (CK) to 8.49 and 8.0 in MaC and FS treatments, respectively. In addition, the NH3 emission for the MaC and FS treatments reduced by 58.3 % and 82.9 %, respectively, whereas the methane (CH4) emission decreased by 22.9 % and 24.9 %, respectively. However, in FS treatment, the carbon dioxide (CO2) and nitrous oxide (N2O) emissions were higher than those in CK. Furthermore, the FS treatment exhibited lower germination index values (71.4 %) and higher electrical conductivity (6.62 mS/cm). Therefore, MaC is suggested as an additive for reducing greenhouse gas emission and conserving nitrogen during sewage sludge composting.

中文翻译：

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化学添加剂对污水污泥堆肥过程中氨和温室气体排放的影响

摘要 研究了氯化镁（MaC）和硫酸亚铁（FS）化学添加剂在污水污泥堆肥中的应用。没有化​​学添加剂的治疗被用作对照组（CK）。评估了 MaC 和 FS 对氨 (NH3) 和温室气体 (CO2、N2O 和 CH4) 排放的影响。结果表明，MaC和FS的加入促进了有机物的降解，提高了堆肥产品的铵盐浓度。在 MaC 和 FS 处理中，最大 pH 值分别从 8.98 (CK) 降至 8.49 和 8.0。此外，MaC 和 FS 处理的 NH3 排放量分别减少了 58.3% 和 82.9%，而甲烷 (CH4) 排放量分别减少了 22.9% 和 24.9%。然而，在 FS 治疗中，二氧化碳 (CO2) 和一氧化二氮 (N2O) 排放量高于 CK。此外，FS 处理表现出较低的发芽指数值 (71.4%) 和较高的电导率 (6.62 mS/cm)。因此，建议将 MaC 作为一种添加剂，用于减少污水污泥堆肥过程中的温室气体排放和节约氮。