College of Water Resources Engineering, Al-Qasim Green University, Al-Qasim, Babylon, 51013, Iraq.
Department of Civil and Architectural Engineering, College of Engineering, Sultan Qaboos University, Al Khoudh, P.O. Box 33, 123, Muscat, Oman.
Sci Rep. 2020 Dec 17;10(1):22209. doi: 10.1038/s41598-020-79395-8.
Odors due to the emission of hydrogen sulfide (HS) have been a concern in the sewage treatment plants over the last decades. HS fate and emissions from extended aeration activated sludge (EAAS) system in Muharram Aisha-sewage treatment plant (MA-STP) were studied using TOXCHEM model. Sensitivity analysis at different aeration flowrate, HS loading rate, wastewater pH, wastewater temperature and wind speed were studied. The predicted data were validated against actual results, where all the data were validated within the limits, and the statistical evaluation of normalized mean square error (NMSE), geometric variance (VG), and correlation coefficient (R) were close to the ideal fit. The results showed that the major processes occurring in the system were degradation and emission. During summer (27 °C) and winter (12 °C), about 25 and 23%, 1 and 2%, 2 and 2%, and 72 and 73% were fated as emitted to air, discharged with effluent, sorbed to sludge, and biodegraded, respectively. At summer and winter, the total emitted concentrations of HS were 6.403 and 5.614 ppm, respectively. The sensitivity results indicated that aeration flowrate, HS loading rate and wastewater pH highly influenced the emission and degradation of HS processes compared to wastewater temperature and wind speed. To conclude, TOXCHEM model successfully predicted the HS fate and emissions in EAAS system.
几十年来，污水处理厂一直关注由于硫化氢（HS）排放而产生的气味。本研究采用 TOXCHEM 模型研究了 Muharram Aisha 污水处理厂（MA-STP）扩展曝气活性污泥（EAAS）系统中 HS 的命运和排放。在不同曝气流量、HS 负荷率、废水 pH 值、废水温度和风速下进行了敏感性分析。预测数据与实际结果进行了验证，所有数据均在限定范围内，归一化均方根误差（NMSE）、几何方差（VG）和相关系数（R）的统计评估接近理想拟合。结果表明，系统中发生的主要过程是降解和排放。在夏季（27°C）和冬季（12°C），分别约有 25%和 23%、1%和 2%、2%和 2%以及 72%和 73%的 HS 被认为是排放到空气中、随废水排出、被污泥吸附和生物降解。在夏季和冬季，HS 的总排放浓度分别为 6.403 和 5.614 ppm。敏感性结果表明，与废水温度和风速相比，曝气流量、HS 负荷率和废水 pH 值对 HS 排放和降解过程的影响更大。总之，TOXCHEM 模型成功预测了 EAAS 系统中 HS 的命运和排放。
