Ammonia Based Aeration Controls: Energy and Non-Energy Impacts
Wastewater treatment plants (WWTP) are continuously implementing various control strategies to meet the expanding demand of complying with stricter regulations on wastewater discharges. One such requirement is preventing ammonia breakthrough. This is typically avoided by elevating the dissolved oxygen (DO) set points in aeration zones. Utilizing DO controls alone has limited applicability and could affect treatment effectiveness within activated sludge process. A few factors that can significantly impact denitrification are high DO concentrations, the absence of proper swing zone controls towards the end of the basins, and also the absence of proper control of internal mixed liquor recycle (IMLR) pumps. In some plants, this is another compliance factor. Water conservation measures have resulted in higher concentrations for influent pollutants different than the plant’s original design intent. This has presented its own challenges in controlling swing zones.
To optimize aeration needed for treatment and to ensure effective nutrient removal in wastewater treatment plants, a controls package involving ammonia analyzers coupled with other sensors is recommended to control aeration blowers and IMLR pumps. Using a feed forward/feedback loop from the remote ammonia analyzer and DO sensors can yield energy savings as opposed to performing under a higher DO set-point. In addition to the energy and cost savings, the non-energy impacts of this energy efficiency investment include improved system performance and reduced environmental impacts of the wastewater discharge pollution.
Lincus Inc. has more than 15 years of experience in energy modeling, energy efficiency consulting, and energy and sustainability consulting. Lincus, with extensive experience in energy projects for water/wastewater treatment facilities, can introduce you to different advanced wastewater control techniques which best suit your facility. Lincus will also evaluate economic and environmental benefits involved with the proposed energy efficiency upgrades at your site.