Measurement And Control Aspect Of Ph Couple With Bidirectional Memosens Technology In Flue Gas Desulfurization Process

Bhupendrakumar R. Patel - Analysis Business Manager, Lower Midwest

Frederick J. Kohlmann - Business Manager, Upper Midwest

pH measurement and control in a power utility is an integral part of process. One of the main externalities of generating power is SO2 [1], which requires efficient lime scrubbers. In a typical coalfired power plant, FGD process will remove 95 percent or more of SO2 in the flue gases. The scrubber efficiency is highly dependent on the pH. Therefore, it requires collaborative input of pH from multiple locations to implement the control strategy within time constraints and cost.

While most of the equipment used for pH measurement appears to be rather simple, in practice however, the underlying principle and understanding of pH process can be very complex. For example, when comparing the lab data with the process solutions, discrepancies often arise. One of the explanations is the temperature difference that occurs while transferring the process sample to the lab. Using inductively coupled digital technology for pH, some of this interference was explained and eliminated from the measurement.

Numerous opportunities were revealed for saving time, as well as the cost and materials in power plants. As results, the externalities of air and water pollution were minimized while saving time, labor hours and materials. The information presented herein may be useful to plant engineers, reliability engineers, managers and operators who are actively involved in the advanced measuring technologies for improving scrubber efficiencies, corrosion control, and energy management for operational efficiencies.