The Camden County (NJ) Municipal Utilities Authority (CCMUA) has installed a new system of valve actuators, two-wire communication loops, and software in the primary sedimentation tank area of its main Delaware No. 1 Water Pollution Control Facility.
According to Herman B. Engelbert, Executive Director of the CCMUA, the automated sedimentation tank system has helped the utility reduce operational and maintenance costs, improve plant efficiency, helped the facility exceed EPA environmental permit parameters, and greatly reduced odor problems in the residential areas near the plant.
Automating the processes associated with the sludge and scum operation in the primary settling tank area was a high priority for CCMUA, said John Connelly, CCMUA's assistant director of operations and maintenance. In 1999, the CCMUA focused on what, if any, improvements could be made to its 10 primary sedimentation tanks.
"Every time we had a heavy rain, an operator would have to manually open as many as 30 influent weir gates. In addition, we had to do a lot of maintenance on 30 existing scum gate actuators from another manufacturer. All in all, the system was outdated and labor intensive," Connelly said.
"When we looked for a new method of control, we wanted a system that would provide a very high level of automation, and one that would require a minimum of maintenance. Also, it needed to interface seamlessly with our Bristol Babcock DCS."
After a thorough search of available technology, CCMUA decided to install 30 Rotork IQ actuators on a Pakscan two-wire communication loop to operate the influent gates at the 10 primary sedimentation tanks. In addition, they retrofitted 30 influent weir gates with IQ actuators.
"We have been very happy with the results," Connelly said. "Most important, we haven't had any failures due to the IQ actuators."
The valve actuators can be adjusted with a hand setting tool or even a laptop PC externally.
"Another important aspect is the dependability of the Pakscan communication loop and the transparent way it interfaces with our DCS through the Pakscan II's master stations," he added.
The Edwin Elliot & Co., a Rotork sales representative located in Lafayette Hill, PA, worked with CCMUA to help make the project a success.
