Aerobic Granular Sludge Piloting in Los Angeles County

摘要

The objective of this project was to design, construct, and operate a pilot-scale aerobic granular sludge (AGS) reactor to evaluate: (1) the feasibility of developing granular biomass at the Sanitation Districts' San Jose Creek East Water Reclamation Plant (SJCE WRP); (2) the characteristics of the granular biomass, such as size and settling behavior; and (3) the performance of the AGS pilot-scale reactor with respect to removal of organics, nitrogen, and suspended solids. Based on a literature review of previous pilot-scale studies that reported the successful development of AGS, a pilot system was designed and constructed for testing at the SJCE WRP. The pilot system was operated over a two year period in three phases based on significant changes in operating conditions to build biomass concentration and improve settling characteristics. The results from this study illustrate that the operating conditions employed were effective for developing granular biomass. For example, to assess the relative settling characteristics of the AGS pilot biomass, sludge volume index plant monitoring data from two of five full-scale step-feed nitrification-denitrification treatment units at the SJCE WRP were recorded during the final phase of operation. The comparison illustrated that a relatively fast settling biomass was developed in the AGS pilot compared to the full-scale units. Results of microscopic examinations and photos taken in the field verified the presence of granules. The majority of the granules in the reactor were in the size range of 0.2 - 0.5 mm. Effluent water quality sampling data collected during the final phase of operation illustrated that the AGS pilot effectively removed organics, nitrogen, and suspended solids.