Click here to enlarge imageAn Envirex Orbal or VLR aerated anoxic process is custom-designed for operators seeking a wide range of treatment and process goals for advanced secondary treatment, simultaneous nitrification-denitrification, biological nitrogen and phosphorus removal or stormwater treatment and reduced energy consumption. Adding a Memcor membrane operating system unit can help plants that are required to meet increasingly strict effluent regulations.
Including the Cannibal solids reduction process with the MBR system will interest plants dealing with biosolids handling and disposal issues.
The custom-engineered plants can also be supplied as a single process program for both new and retrofit applications, thus providing single-point responsibility. This translates into a faster project turnaround and a single permit request for fewer local and state government approvals.
Siemens’ integrated MBR process is comprised of four steps: the aeration process, membrane operating system, SmartMBRTM controls and the Cannibal solids reduction process.
Aeration
The Orbal or VLR process is a multi-stage system of reactors that uses aerated-anoxic technology to achieve nutrient removal and minimize power costs. Simultaneous nitrification/denitrification in the first stage ensures at least 92% total nitrogen removal in the integrated process. Much of the oxygen is transferred in the aerated-anoxic first stage. This translates to a 30% reduction in energy costs. Oxygen transfer and mixing is achieved using premium quality disc aerators.
Membrane Treatment
The membrane operating system, which is at the core of the MBR process, replaces secondary clarifiers for liquid-solids separation. The system uses a two-phase jet stream that scours the membrane surface to prevent solids accumulation. Partitioned fiber bundles allow air to move up and between individual membrane fibers. This process, along with a cross-flow pattern, prevents fouling of the membrane surface.
Following the activated sludge process, membranes in the membrane operating system are immersed in mixed liquor. Vacuum pumps create suction on the membranes, which separate treated effluent from the mixed liquor.
The SmartMBR control system assists in efficient operation of the integrated MBR process, regardless of varying load conditions. The system can interact with existing SCADA software or be installed as new comprehensive controls for the entire plant.
Solids Reduction
The patented Cannibal solids separation module removes trash, grit and inerts that make up 20% to 25% of the mixed liquor in an activated sludge plant. This provides an optimum operating environment for the membrane operating system.
Some of the return sludge is directed to the Cannibal interchange bioreactor. Environmental conditions are carefully controlled in the bioreactor so that aerobic bacteria are conditioned for enhanced degradation, which occurs when the mixed liquor is interchanged back into the main treatment process. The process reduces up to 80% of biological solids.
Case Study
The Calls Creek Wastewater Treatment Plant in Watkinsville, GA, is just one facility that has benefited from using a Siemens integrated biological treatment solution. Adding an MBR system to its existing Orbal process increased the plant’s wastewater treatment capacity. The expansion also helped Calls Creek achieve a superior level of biological treatment and increase capacity of the downstream ultraviolet system through improved transmissivity. Additionally, the upgrade has promoted commercial growth and extended service to unincorporated areas for future residential use.
To learn more about Siemens’ new integrated MBR solutions, please visit WEFTEC Booth 2503 or 2702 in Hall B, or contact Matt Kuzma at (206) 937-1444 or at [email protected].
