The Bardenpho® Process is a five-stage biological treatment process based on the Carrousel® System. It is designed to provide efficient, economical removal of BOD and TSS, and to meet the most demanding effluent standards for effluent nitrogen and phosphorus. By combining the hydraulic efficiency and flexible aeration of the Carrousel® System with dedicated volumes for anaerobic and anoxic reactions, the Bardenpho® Process delivers reliable treatment performance over a wide range of hydraulic and organic loadings, in a simple, energy-efficient facility that is remarkably easy to operate and maintain. Low effluent concentrations of BOD, nitrogen and phosphorus are achieved with little or no costly chemical addition. Reliability has been demonstrated at installations obtaining an AWT effluent (5-5-3-1) (BOD-SS-TN-P). The Bardenpho® Process consists of separate compartments within which anaerobic, anoxic and aerobic environments are maintained. The first stage of the process is the anaerobic basin, a flow-through selector basin that is mechanically mixed and designed to facilitate fermentation and promote the growth of Bio-P bacteria. The second two stages, a mechanically mixed anoxic basin and a Carrousel® aeration basin, are combined into a single basin termed a Carrousel® denitIR® basin. The combination of the anoxic basin and Carrousel® aeration basin allows for the continuous recycle of nitrified and denitrified mixed liquor between the two basins. An internal recycle rate of 10 to 15 times the influent flow is possible and this provides over a 90% reduction in nitrogen in these two stages. An overflow weir in the Carrousel® channel wall connects to the downstream fourth stage, the second anoxic basin where nitrates are reduced to less than 1 mg/l. A small reaeration makes up the fifth stage of the process and provides final polishing prior to conveyance to the secondary clarifiers.

Features and Benefits

• All the benefits of the Carrousel® and denitIR® Systems
• Stable performance over wide variations in loadings
• Little or no chemical expense
• Reliable treatment to AWT standards (5-5-3-1) – (BOD-SS-TN-TP)
• Simple, forgiving process
• Minimal operation and maintenance requirements.
• Alkalinity Recovery
• Low power requirements

info.ewt@glv.com