In water and wastewater treatment system, the stability of flow entering the system is required. The objective of the equalization pond is to minimize or control fluctuations of wastewater characteristics to achieve optimum conditions in subsequent processing. The variation of the liquid waste stream determines the size and type of pond equalization. This equalization pool is needed to adjust the fluctuations of the discharge, nutrient, organic loading, and pH. So that wastewater can be treated in conditions that nearly constant. Wastewater flows constantly from the equalization pond to the next unit.
In addition to functioning as a flow regulator, equalization can also be combined with neutralization. The addition of acids and bases can be done for pH neutralization of the influent of wastewater, so as not to interfere with microbiological work in biological processing. Nutrients can also be added to avoid lack of nutrients in biological treatment units. If any substances – substances that are toxic in wastewater can be processed in a pool equalization by physical and chemical processes.
Advantages of Using Equalization Pond:
- The efficiency of biological processing will be increased because of no shock on loading quantity and quality.
- The effluent quality and the thickening process in the second sedimentation is better because the solid load is constant.
- Improve control on chemicals added for chemical treatment of the wastewater.
Equalization Pond suggested location:
- Equalization pond can be located after primary treatment
- Equalization pond can be located before the first settling basin and biological system, but the design should pay more attention to the problem of stirring to avoid deposition of solids and varying concentrations. And it is also required good aeration to avoid odor problems.
The volume required for equalization pond:
The volume required for the equalization bath is determined by using an inflow mass diagram, where the cumulative discharge can be correlated with its cumulative daily average flow. The maximum difference between this flowrate data can be used as the volume of the equalization pond.