School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, Shannxi Province, 710049, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China.
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China.
Chemosphere. 2022 Jun;296:133958. doi: 10.1016/j.chemosphere.2022.133958. Epub 2022 Feb 14.
Sulfide inhibition is a critical task for the secure operation of sewer systems, and oxidation is usually utilised to achieve this purpose. However, the effects and mechanism of oxidation during the transformation of sulfur-associated pollutants in gas-liquid-solid phases of sewers have not been extensively evaluated. In this study, a method for quantifying sulfur-associated pollutant exchange pathways in gas-liquid-solid phases of sewers was established. The results showed that although the concentration of sulfide decreased under different oxidation conditions, the consumption of sulfate in sewers clearly increased. The transformation strength of elemental sulfur was high (18.65 mg/L, 35.52% of sulfate from the influent) and the accumulation of sulfate in sediment was obvious (3.49 mg/L, 6.65% of sulfate from the influent). Higher concentrations of sulfate in the influent promoted the generation of sulfide in sediment (8.98 mg/L, 17.10%). Thus, the oxidation process led to the generation of more absolute sulfide. In addition, promoting the metabolism of sulfate-reducing bacteria enhanced the loss of organic carbon in sewers, which might weaken the efficacy of nitrogen and phosphorus removal in wastewater treatment plants. Based on the evaluation of the exchange pathways of sulfur-associated pollutants in sewers, further studies into sulfide inhibition in sewers should consider the above issues to enhance the safe management of urban sewers.
硫化物抑制是污水系统安全运行的关键任务，通常采用氧化法来实现这一目的。然而，在污水中气相、液相和固相中硫相关污染物转化过程中氧化的影响和机制尚未得到广泛评估。本研究建立了一种定量分析污水中气相、液相和固相中硫相关污染物交换途径的方法。结果表明，尽管在不同氧化条件下硫化物浓度降低，但污水中硫酸盐的消耗明显增加。单质硫的转化强度高（18.65mg/L，占进水硫酸盐的 35.52%），硫酸盐在沉积物中的积累明显（3.49mg/L，占进水硫酸盐的 6.65%）。进水硫酸盐浓度较高会促进沉积物中硫化物的生成（8.98mg/L，占进水硫酸盐的 17.10%）。因此，氧化过程导致绝对硫化物生成量增加。此外，硫酸盐还原菌代谢的促进会导致污水中有机碳的损失增加，从而可能削弱污水处理厂氮磷去除的效果。基于对污水中硫相关污染物交换途径的评价，进一步研究污水中的硫化物抑制应考虑到上述问题，以增强城市污水系统的安全管理。
