Electric utilities must regulate power production in response to changing demand. The ability to do this rapidly and efficiently is a valuable asset that requires precise, efficient boiler combustion control; however, obtaining the requisite control can be a challenge, even at steady state. Fuel and combustion air flow are controlled by modulating a variety of fans and dampers, and without actuators capable of positioning the dampers precisely, it is impossible to achieve the precise combustion control required for automatic load dispatch.

A JEA power station, which operates two of the largest Circulating Fluidized Bed (CFB) combustors in use, recently completed a plant upgrade to improve efficiency and reduce maintenance costs. A large part of this project focused on improving steam temperature control. Beck high torque 22-409 actuators were installed on the critical Reheat damper applications to provide the precision and reliability required.

PPG Industries is a specialty chemical company that serves the aerospace, architectural and packaging industries, to name a few. In 2006, PPG’s West Virginia facility had an initiative to reduce fuel and maintenance costs associated with its boilers. As part of this initiative, PPG planned to replace their pneumatic actuators over the next few years.

The Carmeuse lime plant in Maysville, KY has had Beck actuators installed on most of their important control applications for over 30 years. These include primary air, coal mill air, preheater vents, and kiln ID fans. Many of the units installed during original plant construction in the mid-1970’s are still in service. The plant experienced a torque related problem with a 34 year old actuator on a critical ID fan damper actuator. A new motor was installed, without having to remove the actuator from service, returning the damper to operation quickly.

The ethanol blending process is a critical part of petrol terminal operation and has a significant impact on product quality, meeting environmental regulations and profitability. Optimising the process is very important, but does present some control challenges. For example, thermal expansion of petrol and ethanol do not occur at the same rate, and the blended mixture has to be isolated from water due to ethanol’s miscibility in water.