E-Zine April 2015
A common application of control equipment in water and wastewater treatment is the management of pumping stations. Pump stations are found in such varied applications as the clearwell of gravity filtration systems in wastewater treatment plants, at the base of water storage tanks, as booster stations for feed to distribution grids and even on golf courses for irrigation. In wastewater treatment, pump stations are found before the influent of the treatment plant (called lift stations), and at the outfall of the treatment plant to move the treated wastewater to the actual discharge point.
Pump stations are available in two forms. Sometimes, an engineering firm is retained to design and draw plans for a custom pumping plant. Other times, the water company or wastewater utility purchases a pre-designed “package” pump station complete from a vendor, and hires a contractor to install it and connect it to the system. There are advantages and disadvantages to both forms.
Before the design is started, or before the requisition to buy a package pump station is written, there are issues on which the end user must decide, including the overall control strategy such as whether the pump is turned on/off or modulated.
Selecting an inexpensive control strategy may result in the installation of equipment that has a lower purchase cost, but a much higher operating cost that could offset the cost savings in a short period of time.
Click here to read “Pump Station Control: On/Off Control Strategy (Part 1)”
From Flow Control (June 2002)