Department of Environmental Health Engineering, Faculty of Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
Faculty of Chemistry, Bu-Ali-Sina University, Hamadan Zip Code 65174, Iran.
Ecotoxicol Environ Saf. 2019 Jan 30;168:120-126. doi: 10.1016/j.ecoenv.2018.10.069. Epub 2018 Oct 29.
In this work, the efficiencies of Fenton catalytic and sonolysis processes were investigated separately and in combination together for the treatment and reduction of sludge volume. Moreover, the effects of operating parameters such as retention time, initial pH, iron concentration, and HO concentration on COD reduction as well as the proportion of volatile solids to total solids (VS/TS) were studied. Finally, the effects of these processes on the sludge volume index (SVI) and sludge volume reduction (SVR) were evaluated. According to the results, the retention time of 60 min, pH = 3, hydrogen peroxide concentration of 0.13 M/L, and iron concentration of 2 mM/L were achieved as the optimum values. Furthermore, the SVR and SVI removal efficiencies in the Fenton process were 19% and 25%, respectively, but the removal efficiency in sonolysis process was very low and can be ignored. Under optimum conditions in sono-Fenton (SF) process, the SVR and SVI removal efficiencies were 55.7% and 83%, respectively. The results showed that by combining sonolysis and Fenton processes; due to the synergistic effect of ultrasonic waves, Fenton agent, and the production of more hydroxyl radicals; the COD removal efficiency increased to 77%, and the proportion of VS/TS in row activated sludge was reduced from 75% to 26%. Generally, by combining sonolysis and Fenton processes, the removal efficiency increased significantly as compared to separate processes owing to the production of more oxidizing agents and improving mass transfer.
在这项工作中，分别研究了芬顿催化和超声降解过程的效率，并将它们结合起来用于处理和减少污泥体积。此外，还研究了操作参数（如停留时间、初始 pH 值、铁浓度和 HO 浓度）对 COD 减少以及挥发性固体与总固体的比例（VS/TS）的影响。最后，评估了这些过程对污泥体积指数（SVI）和污泥体积减少（SVR）的影响。结果表明，当停留时间为 60 分钟、pH 值为 3、过氧化氢浓度为 0.13 M/L 和铁浓度为 2 mM/L 时，可达到最佳值。此外，芬顿过程的 SVR 和 SVI 去除效率分别为 19%和 25%，但超声降解过程的去除效率非常低，可以忽略不计。在 Sono-Fenton（SF）过程的最佳条件下，SVR 和 SVI 的去除效率分别为 55.7%和 83%。结果表明，通过结合超声和芬顿过程，由于超声波、芬顿试剂的协同作用以及产生更多的羟基自由基，COD 去除效率提高到 77%，并且好氧活性污泥中 VS/TS 的比例从 75%降低到 26%。一般来说，与单独的过程相比，通过结合超声和芬顿过程，由于产生了更多的氧化剂并改善了传质，去除效率显著提高。
