FIS replaced the existing stack and installed O2 and temperature indicators for better control of the Oxygen levels and temperatures exiting the stack. The new stack was provided with connected ladders and platforms. The existing stack didn’t have a damper for draft control. The stack damper is pneumatically operated. Minimum limit stop has been provided on linkage side of damper frame so as to prevent it from being fully closed. A position transmitter has been provided to know the damper opening position. The stack damper is provided to ensure that the draft at arch is maintained at the design level of (-) 0.1” WC under all operating conditions.
The energy savings after the revamp were between $780,000 - $1,070,000 per year. The total cost of the project for the design services, engineering services, fabrication and installation was $2,500,000. The project payout was estimated to be less than 2 years. This heater was successfully commissioned in March 2008.