Upgrade the aeration system to diffused air from mechanical surface aeration

completed

Aeration in a wastewater treatment plant is the process of adding oxygen into wastewater to accelerate the biological breakdown of the wastewater pollutants. The current method of aeration at Cobourg’s Normar Road plant is the use of mechanical paddle aerators. This technology relies on the action of surface paddles producing plumes of droplets above the surface of the liquid in the tank. The droplets have a larger surface area for oxygen transfer from the air to the droplets than the liquid surface in the tank alone. Diffused air systems on the other hand involve the installation of piping along the bottom of the tank through which air is pumped, producing bubbles which rise to the surface transferring oxygen to the liquid. This system is superior to the mechanical paddle aerators in several ways; the oxygen transfer is more efficient, mixing is much better, and the electric motors used to power the system consume less energy than the mechanical aerator motors. The increased efficiency of the oxygen transfer process increases the capacity of the plant which postpones the need to expand the plant beyond the current expected time.