Shanghai Engineering Research Center of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
Shanghai Solid Waste Management Center, Shanghai, 200235, China.
Environ Sci Pollut Res Int. 2021 Feb;28(5):6090-6098. doi: 10.1007/s11356-020-10799-9. Epub 2020 Sep 28.
Sewage sludge is the major by-product of wastewater treatment plants, and about 30% readily biodegradable organic matters might be reused through the mass reduction process, which could be also reduced the disposal fee. In this study, the microbubble ozonation (MB-O) was employed to improve the oxidation efficiency for sludge solubilization. At 160 mgO/gSS, the maximum mixed liquor suspended solids (MLSS) reduction ratio was 37.5% and the protein and polysaccharide contents increased to 31.6 and 138.6 mg/L, respectively. It was proposed that aromatic protein and soluble microbial in sludge were oxidized preferentially by MB-O, and the dissolved organic matter (DOM) fractions (mainly humic-acid-like substances) exhibited low degradability according to the variations of fluorescence excitation-emission spectrum coupled with fluorescence regional integration. MB-O could enhance the settleability, but deteriorate sludge dewaterability at low dosage (< 160 mgO/gSS) due to a reduction in particle size from 61.7 to 47.5 μm. MB-O has a good performance on the mass reduction of sludge through the improvement of the radical generated.
污水污泥是废水处理厂的主要副产品，约 30%的易生物降解有机物可以通过质量减少过程再利用，这也可以降低处理费用。在本研究中，采用微气泡臭氧化（MB-O）来提高污泥溶解的氧化效率。在 160mgO/gSS 时，最大混合液悬浮固体（MLSS）的去除率为 37.5%，蛋白质和多糖含量分别增加到 31.6 和 138.6mg/L。据荧光激发-发射光谱与荧光区域积分变化推测，MB-O 优先氧化芳香族蛋白质和溶解性微生物，溶解有机物（DOM）组分（主要为类腐殖质物质）的降解性较低。MB-O 可以通过增加自由基的生成来提高污泥的沉降性能，但在低剂量（<160mgO/gSS）下会降低污泥的脱水性能，因为颗粒尺寸从 61.7 减小到 47.5μm。MB-O 通过改善自由基的生成，对污泥的减量化具有良好的效果。
