Return on Investment for Combustion Optimization
A thorough performance optimization of combustion systems and pollution control systems directly leads to significant savings in maintenance and operating costs. Optimization not only improves performance and efficiency, it can also extend run time between forced outages. Significant savings resulting from these efforts have been documented.
Over several years, one CC&E client operating two 500+ MW boilers experienced load de-rates as well as unplanned outages caused by slagging events. The result was a loss in generation revenue. During peak times, when prices and load demand were up, as slagging problems worsened, lost revenue increased.
In 2011, CC&E conducted a comprehensive combustion tuning and optimization program on these boilers, focusing on fuel and air flow and distribution. The multi-component effort began with calibration of all primary and secondary airflow control indications. We then tested and balanced pipe-to-pipe flow distribution of coal from each pulverizer. Next, air in-leakage across back-end components of the unit was measured, mapped and documented. Finally, we used a multi-point gas sampling grid at the economizer outlet for analysis of combustion gases for O2, NOx, and CO using our mobile emissions trailer. Understanding the leakage information and using the spatial gas profiles, we made improvements to combustion air distribution (burner air and OFA) resulting in much better-balanced combustion on both boilers.
Post-optimization operating results showed increased boiler runtime between unplanned outages and an elimination in slag-related derates. 2011 GADS data showed no lost generation from slag events compared to 38,002 MW-hrs lost in 2010 from these boilers. The combined lost generation revenue from these two boilers in 2010 would equal $1.7M at $45/MW-hr (LMP).
Because of results like this, multiple large utilities trust CC&E enough to award us blanket contracts to test all their sites. These contracts include boiler performance testing, pulverizer testing with coal flow balancing, air flow testing, combustion tuning, and SCR AIG tuning.