Abstract:

In 2004, the Newtown Creek Wastewater Treatment Plant (WWTP), designed for 13.6 m³/sec average daily flow (ADF) was operating under an interim permit with new secondary treatment permit limits scheduled to go into effect in January 2008. The facility is currently undergoing a plant-wide upgrade that includes increasing the biological treatment facilities by 50% (from two to three treatment batteries) and changing the process from High Rate Modified Conventional Activated Sludge operation (SRT <0.5 days) to Low Solids Retention Time (SRT 1.8 - 2.2 days) Step Feed Activated Sludge operation. By January 2008, all three batteries were to be operational but only half the secondary system would be fully upgraded to the step feed process (Scheduled for completion in 2013). With no primary treatment facilities and the requirement to treat all influent flow to a minimum of 27.2 m³/sec during rain events in this interim period, stable operation of the existing facility, particularly during rain events, was expected to be a challenge.

Therefore, a Demonstration Project was performed in two aeration/final tank trains from December 2004 until December 2005. The purpose of this testing was to gain experience in the operation and performance of the existing South and South Central Batteries prior to the January 1, 2008 Consent Order date when full secondary treatment would be required. In developing the Demonstration Project, the ability to prevent solids loss during wet weather operation was identified as the critical operating parameter to success. Rapid response to flow increases during rain events was determined to be the goal in preventing solids loss. The Demonstration Project confirmed the rapid response to flow increases during rain events as a critical parameter for the success of preventing solids loss during rain events.

Keywords: WET WEATHER; STEP FEED GATE ADDITION; FINAL SETTLING TANK; HYDRAULIC LOADING; SOLIDS LOADING

Document Type: Research article

DOI: 10.2175/193317708X335190