Saha Moutoshi, Srinivasan Asha, Liao Ping Huang, Lo Kwang Victor
Department of Civil Engineering, University of British Columbia, Vancouver, Canada.
Environ Technol. 2023 Mar;44(8):1114-1124. doi: 10.1080/09593330.2021.1994655. Epub 2021 Nov 15.
The microwave enhanced advanced oxidation process (MW-AOP) has been applied to pre-treat different sludge types and high solids content. Secondary sludge not only had the highest solids and nutrient content but also yielded higher treatment efficiency than primary or mixed sludge. In the case of secondary sludge with 4% total solids (TS), the total suspended solids (TSS) concentration was reduced by 32% while soluble chemical oxygen demand concentration increased from 1% to 40% after treatment at 110°C. A high level of nutrient release was also achieved; about 65% total phosphate (TP) solubilized at 110°C. The degree of secondary sludge disintegration was dictated by temperature and hydrogen peroxide dosage. The optimal operating temperature for the system was 110°C, and sludge containing TS up to 8% was treated effectively. Secondary sludge with 8% TS had a TSS reduction of 41% after treatment at 110°C while COD solubilization was about 45%; about 55% TP was solubilized at 10 min holding time. Treatment of sludge with higher solids content would allow for handling larger amounts of sludge at a given period and reduce heating cost per unit of treated sludge. The inter-relationship between the degree of sludge disintegration and changes in chemical and physical properties was also clearly demonstrated here. The treated sludge would be an ideal substrate for anaerobic digestion or phosphorous recovery processes. High levels of nutrients (phosphorus and nitrogen) and metal release, and solids disintegration from sludge containing high solids content would make subsequent resource recovery processes more effective and economical.
微波强化高级氧化工艺（MW-AOP）已应用于不同类型污泥及高固体含量污泥的预处理。二次污泥不仅固体和养分含量最高，而且处理效率也高于一次污泥或混合污泥。对于总固体含量（TS）为4%的二次污泥，在110°C处理后，总悬浮固体（TSS）浓度降低了32%，而可溶性化学需氧量浓度从1%增加到了40%。同时也实现了高水平的养分释放；在110°C时约65%的总磷（TP）被溶解。二次污泥的解体程度取决于温度和过氧化氢用量。该系统的最佳运行温度为110°C，能有效处理TS含量高达8%的污泥。TS含量为8%的二次污泥在110°C处理后TSS降低了41%，而化学需氧量的溶解率约为45%；在保持10分钟时约55%的TP被溶解。处理更高固体含量的污泥能够在给定时间段内处理更多污泥，并降低单位处理污泥的加热成本。本文还清楚地展示了污泥解体程度与化学和物理性质变化之间的相互关系。经处理的污泥将是厌氧消化或磷回收工艺的理想底物。高含量的养分（磷和氮）及金属释放，以及高固体含量污泥的固体解体，将使后续的资源回收工艺更有效且经济。
