MOB Process in an SBR

The Washington Township Waste Authority (WTWA) SBR is a two train, 250,000 GPD SBR process with 4-hr cycle times. In March 2020, WTWA installed Nuvoda’s MOB Process in one of the two trains. Over the course of a ten month trial, a significantly increased flow through the MOB Process train was used to test and demonstrate the MOB Process’ ability to handle both increased flow and peak flow events(> 1 Ox design). Results showed the MOB Process in the SBR was capable of handling up to 70% increased flow above design while maintaining effluent discharge requirements, and in the case of phosphorus, lowering effluent levels at increased flow. Furthermore, the MOB Process also handled the very high peak flow events(> 1 Ox design) while maintaining effluent TSS levels and clarity.

PROJECT BACKGROUND

Throughout the trial, the WTWA SBR have collaborated with Nuvoda to conduct sample collections and effluent quality tests twice a week. During the trial, the Washington Township Waste Authority SBR conducted flow diversion with weirs to slowly increase flow distribution into the MOB Process train (from rated capacity to 70% increase over rated capacity). These process changes were recorded and presented in this report. The unchanged SBR will be labeled as “CAS” (Conventional Activated Sludge), and the MOB trial SBR will be labeled as “MOB”.