Sustainability Archive » Reduced Aeration Use

Evaluation of a Full-Scale Activated Sludge Real Time Control System

justin — Fri, 27 Aug 2010 19:47:49 +0000

In the past few years both power and chemical costs have increased considerably. In the UK, commercial power costs have increased from 4.5p/kWh to 7.5p/kWh within a year and future power cost inflation is expected to be at least 11% per annum. The water industry constantly has to meet increasingly stringent discharge consents within smaller site footprints and on this basis water utilities are increasing the use of the energy intensive activated sludge processes (ASP). Recent trials conducted by MWH at a 250,000 population equivalent ASP on the south coast of the UK show that the implementation of Real Time Control (RTC) for both aeration and methanol dosing control can significantly reduce the operating cost of the activated sludge process whilst still delivering the required effluent quality. Initial results show a consistent reduction in aeration costs of 20 % with a corresponding reduction in methanol cost of 50 %. Source: WEFTEC 2009 Proceedings

Utilizing Automatic Dissolved Oxygen and Internal Recycle Set-Point Control at Abington WWTP in Southeastern Pennsylvania

justin — Fri, 25 Jun 2010 20:25:19 +0000

As permit requirements for effluent quality at wastewater treatment plants continue to become more stringent, intelligent control systems are needed to ensure optimal performance of the secondary treatment process. Such a control system was installed at Abington Wastewater Treatment Plant in southeastern Pennsylvania in 2005. Since that time, the control system has been optimizing dissolved oxygen set-points based on real-time loading with the goal of minimizing aeration requirements and maximizing process reliability. In 2009, after a plant upgrade, internal recycle optimization was added to the system. The benefits of this system have been a 5.5% reduction in aeration requirements, consistently meeting effluent ammonia goals, and optimal use of the anoxic volume for denitrification. Long term performance data of the upgraded system will be available once sufficient time has passed to fully evaluate the system. Source: WEFTEC Proceedings 2009