Everything Old Is New Again (The Rebirth of a Wastewater Treatment Plant Through Automation)

Automated control of a facility is often one of the principal improvements desired to ease demands placed on operators. Plant personnel are required to maintain processes within governed parameters that in conjunction with increasingly smaller staff numbers can present challenges. One challenge encountered frequently with plant personnel is the aversion to change and use of new technologies. This problem was clearly evident in the early stages of construction where formally manually operated processes were switched back into manual control after being fully automated and switched into auto mode. This issue was due mainly to thoughts that “people” jobs were being replaced with computers. Pinellas County constantly monitors the condition of the plants and the staff's abilities to maintain the condition. The installation of a fully automated system not only is a valuable tool in maintaining control over the processes it allows the Operator to view the entire plant processes. The result is time savings, more efficient use of chemicals and other consumables, and improved maintenance capabilities.The use of the new automated system employed for this project has resulted in the following new abilities of plant operators:Through the use of trend charting provided by the Programmable Logic Controller (PLC),What/If scenarios can be presented to determine possible outcomes, maximize plant performance, and trouble shoot processes.Polymer usage versus sludge feed rates can be optimized to provide cost benefits.Operators were provided handheld Personal Digital Assistants (PDA) which allowed both monitoring and operating the entire plant from any point in the facility.During second and third shifts this tool has allowed operators to respond to emergencies with greater efficiency.