URS Group and their test team will evaluate sorbent injection for mercury control on sites with low-SCA ESPs, burning low sulfur Eastern bituminous coals. Full-scale tests will be performed at Plant Yates Units 1 and 2 to evaluate sorbent injection performance across a cold-side ESP/wet FGD and a cold-side ESP with a dual NH3/SO3 flue gas conditioning system, respectively. Short-term parametric tests on Units 1 and 2 will provide data on the effect of sorbent injection rate on mercury removal and ash/FGD byproduct composition. Tests on Unit 2 will also evaluate the effect of dual-flue gas conditioning on sorbent injection performance.

Results from a one-month injection test on Unit 1 will provide insight to the long-term performance and variability of this process as well as any effects on plant operations. The goals of the long-term testing are to obtain sufficient operational data on removal efficiency over time, effects on the ESP and balance of plant equipment, and on injection equipment operation to prove process viability.

This sorbent injection technology is targeted as the primary mercury control process on plants burning low/medium sulfur bituminous coals equipped with ESP and ESP/FGD systems. Approximately 38,000 MW of generating capacity exist for bituminous coal-fired power plants with high-efficiency particulate control devices followed by wet lime/limestone FGD. In addition, about 70% of the ESPs used in the utility industry have SCAs less than 300 ft2/1000 acfm. Therefore, the data from this sorbent injection project will be applicable to a large portion of the market.

One of the purposes of the sorbent injection program is to generate data to show the economic benefits of sorbent injection in a bituminous coal environment with an ESP or ESP/FGD configuration. The program is aimed at using low-cost sorbents. Data from this program will be used to perform an economic analysis of the costs associated with full-scale implementation of a sorbent-based injection system for these types of facilities.