Development of Process Models for Planning, Operations, and Training


  • Phill Yi - Hazen and Sawyer

Water resource recovery facilities (WRRFs) both in the United States and other countries are required to achieve ever more stringent limits on nutrients. As such many facilities are implementing online sensor technology, process modeling, and other means to achieve these limits while optimizing processes to minimize the use of resources, energy, and capital. A case study of the Metropolitan Sewer District of Greater Cincinnati (MSDGC) is discussed to illustrate one example of an operations tool (Ops Tool) developed to equip plant personnel with better understanding of the impacts of process changes. MSDGC owns and operates seven major water resource recovery facilities (WRRFs) ranging in size from 1.5 MGD to 130 MGD, with three of the seven plants treating wastewater from combined sewers. MSDGC pursued development of the Ops Tool for six of their facilities to provide several levels of benefit to the staff including what-if scenario operations planning, planning for shutdowns and scheduled maintenance, wet weather operations, plant optimization (energy and chemicals), and training for new staff. The Ops Tools can capture overall plant behavior and provide a larger overview of plant operation and performance based on user input. The current Ops Tools are “off-line” in the sense that data collected must be manually transferred as inputs into the tool for simulation. The Ops Tools bend a stereotypical design process model into a training tool, evaluation of process control strategy evaluation guide, and a platform for integrating sensor data for real-time or “on-line” modeling of a facility. The Ops Tools leverage previous capital investments in process models to create internal tools for process troubleshooting, optimization, and developing standard protocols or process control strategies. Although currently an “off-line” tool, there are opportunities to integrate real-time sensor data to switch to an “on-line” approach. This presentation will focus on the development and calibration of the operations tool for planning and design and some examples uses as a “tool in the toolbox” for operations staff for plant optimization and training. The presentation will also cover feedback from the utility on lessons learned and considerations for implementing an operations tool including internal support and training necessary for maintaining the Ops Tools.

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Horizons Fall 2017 (pdf)

Horizons showcases significant water, wastewater, reuse, and stormwater projects and innovations that help our clients to achieve their goals, and can help you achieve yours. Articles are written by top engineers and process group leaders, demonstrating and explaining the beneficial application of a variety of technologies and tools.

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