Monti Alessandro, Hall Eric R, Dawson Robert N, Husain Hadi, Kelly Harlan G
Environmental Engineering Group, Department of Civil Engineering, The University of British Columbia, 6250 Applied Science Lane, Vancouver, British Columbia, Canada.
Biotechnol Bioeng. 2006 Jul 5;94(4):740-52. doi: 10.1002/bit.20896.
A membrane-enhanced biological phosphorus removal (MEBPR) process was operated in parallel with a conventional EBPR (CEBPR) process under challenging operating conditions to uncover fundamental differences in their ability to remove chemical oxygen demand (COD), nitrogen (N), and phosphorus (P) from municipal wastewater. Both systems exhibited the same potential to achieve excellent soluble-P removal when a favorable COD to P ratio was maintained in the influent. The MEBPR train generated a superior effluent quality when measured as total P. The CEBPR effluent contained significantly lower levels of nitrates due to the extra denitrification occurring in the sludge blanket of the secondary clarifier. The observed sludge yield in the MEBPR system was estimated to be between 0.23 and 0.28 g VSS/g COD, and this was 15% lower than the CEBPR sludge yield. When the influent volatile fatty acids (VFAs) became limiting, the CEBPR train exhibited better performance in the removal of soluble-P, due to the higher observed sludge yield and an overall greater denitrification activity that led to a more efficient use of VFAs in the anaerobic zone. After experiencing a severe deterioration of the biological P activity in both processes, the MEBPR train exhibited faster recovery than the CEBPR side. In this experimental work, it was demonstrated that an MEBPR process can sustain long-term satisfactory bio-P performance at HRTs as low as 7 h. However, the lower sludge yield and the reduced denitrification capacity are two important factors that impact the design of high rate membrane-assisted biological nutrient removal (BNR) processes.
在具有挑战性的运行条件下，膜增强生物除磷（MEBPR）工艺与传统的强化生物除磷（CEBPR）工艺并行运行，以揭示它们从城市废水中去除化学需氧量（COD）、氮（N）和磷（P）能力的根本差异。当进水维持有利的COD与P比例时，两个系统都具有实现优异溶解性磷去除的相同潜力。以总磷衡量时，MEBPR系列产生了更优质的出水。由于二次沉淀池污泥层中发生额外的反硝化作用，CEBPR出水的硝酸盐含量显著更低。MEBPR系统中观察到的污泥产率估计在0.23至0.28 g VSS/g COD之间，这比CEBPR污泥产率低15%。当进水挥发性脂肪酸（VFA）成为限制因素时，CEBPR系列在溶解性磷去除方面表现出更好的性能，这是由于观察到的污泥产率更高以及总体上更大的反硝化活性，从而导致在厌氧区更有效地利用VFA。在两个工艺中的生物除磷活性都经历严重恶化后，MEBPR系列的恢复速度比CEBPR更快。在这项实验工作中，证明了MEBPR工艺在低至7小时的水力停留时间（HRT）下可以维持长期令人满意的生物除磷性能。然而，较低的污泥产率和降低的反硝化能力是影响高速率膜辅助生物营养物去除（BNR）工艺设计的两个重要因素。
