Chemical Engineering Department, University of Ottawa, Ottawa, Ontario, Canada.
Water Environ Res. 2011 Jun;83(6):549-59. doi: 10.2175/106143010x12780288628651.
Thickened waste activated sludge (TWAS) was pretreated with microwave irradiation to temperatures higher than the boiling point (between 110 and 175 degrees C) using different microwave intensities. Biochemical methane potential (BMP) assays demonstrated that, although mesophilic anaerobic digestion (MAD) inoculum used was acclimated for 4 months with microwave pretreated TWAS (to 175 degrees C), acute methanogenic inhibition was observed. Additionally, the microwave conditions applied increased the soluble chemical oxygen demand (sCOD)-to-total COD (tCOD) ratio; however, no significant enhancement in the rate or extent of TWAS stabilization was observed for the microwave-pretreated samples. Microwave pretreatment to between 110 and 175 degrees C at lower microwave intensity with a better acclimated MAD inoculum (acclimatized for an additional 3 months) resulted in minimal methanogenic inhibition (improved acclimation) and improved the rate and extent of TWAS biodegradation, as determined by volatile solids removal and biogas production (microwave applied at lower microwave intensity). The TWAS pretreated to 175 degrees C produced 31 +/- 6% more biogas than the control (raw TWAS) by the 18th day of the BMP test, whereas the highest improvement observed from the first set of BMP experiments was 13 +/- 1%.
采用不同微波强度，将高于沸点（110-175°C 之间）的微波辐射应用于浓缩剩余活性污泥（TWAS）预处理。生物化学甲烷潜能（BMP）试验表明，尽管中温厌氧消化（MAD）接种物已经适应了用微波预处理的 TWAS（至 175°C）4 个月，但仍观察到急性甲烷抑制。此外，所应用的微波条件增加了可溶解性化学需氧量（sCOD）与总化学需氧量（tCOD）的比值；然而，对于微波预处理的样品，没有观察到 TWAS 稳定化的速率或程度有显著提高。在较低的微波强度下，将微波预处理至 110-175°C，并采用更好适应的 MAD 接种物（再适应 3 个月），导致最小的甲烷抑制（更好的适应），并改善了挥发性固体去除和沼气生产（微波在较低的微波强度下应用）过程中 TWAS 的生物降解速率和程度。在 BMP 试验的第 18 天，预处理至 175°C 的 TWAS 比对照（原始 TWAS）多产生了 31±6%的沼气，而从第一组 BMP 实验中观察到的最高改进为 13±1%。
