Improving Aerobic Digestion by Prethickening, Staged Operation, and Aerobic-Anoxic Operation: Four Full-Scale Demonstrations

摘要

Four full-scale aerobic digesters were studied to determine the effects of prethickening, staged operation, and aerobic-anoxic operation on digester performance. Prethickening is expected to enhance aerobic digestion by reducing hydraulic flow rates, thereby allowing increased solids retention time (SRT) value and temperature elevation. Staged operation increases the plug flow characteristic of the digester, by reducing hydraulic flow rates, and pathogen destruction. Aerobic-anoxidc operation results in denitrification, which can provide approximately neutral pH that enhances nitrification, digestion, and nitrogen removal.