Department of Inorganic Chemistry and Chemical Engineering, University of Cordoba, Campus Universitario de Rabanales, Edificio Marie Curie (C-3), Ctra. N IV, km 396, 14071, Cordoba, Spain.
Appl Biochem Biotechnol. 2021 Mar;193(3):777-790. doi: 10.1007/s12010-020-03454-z. Epub 2020 Nov 13.
This research study evaluates various pre-treatments to improve sewage sludge solubilization prior to treatment by mesophilic anaerobic digestion. Microwave, thermal, and sonication pre-treatments were compared as these pre-treatments are the most commonly used for this purpose. The solubilization of sewage sludge was evaluated through the variation in soluble total organic carbon (sTOC, mg/L) and soluble total nitrogen (sTN, mg/L). Thermal and microwave pre-treatments increased sTOC/VS by 19.2% and 83.4% (VS, total volatile solids), respectively, after applying lower specific energy through (20 kJ/g TS, approximately) (TS, total solids) unlike the sonication pre-treatment, which required 136 kJ/g TS. Although sTN content did not increase significantly with the pre-treatments with respect to sTOC, both showed proportional trends. Sonication pre-treatments allowed the highest increase in volatile fatty acids (VFA) with respect to the raw sewage sludge (15% ∆VFA/sTOC). Methane production with and without pre-treatment was also evaluated. Methane production increased by 95% after applying sonication pre-treatment compared to the methane production of raw sewage sludge. Thermal and microwave pre-treatments entailed lower improvements (29% and 20%, respectively). Economically, thermal pre-treatments were the most viable alternative at real scale. Graphical abstract.
本研究评估了各种预处理方法，以改善中温厌氧消化前污水污泥的溶解性能。比较了微波、热和超声预处理，因为这些预处理方法是最常用于该目的的方法。通过可溶总有机碳（sTOC，mg/L）和可溶总氮（sTN，mg/L）的变化来评估污水污泥的溶解性能。与超声预处理（136 kJ/g TS）相比，热和微波预处理分别通过施加较低的比能（20 kJ/g TS，约）（TS，总固体），使 sTOC/VS 增加了 19.2%和 83.4%（VS，总挥发性固体），而超声预处理则不需要。尽管与 sTOC 相比，预处理对 sTN 含量没有显著增加，但都显示出比例趋势。与原始污水污泥相比，超声预处理允许挥发性脂肪酸（VFA）的增加幅度最大（15% ∆VFA/sTOC）。还评估了有和没有预处理的甲烷生产。与原始污水污泥的甲烷产量相比，超声预处理后甲烷产量增加了 95%。热和微波预处理的改进幅度较低（分别为 29%和 20%）。从经济角度来看，热预处理在实际规模下是最可行的替代方案。
