Thomas Hill Energy Center SCR Retrofit

Thomas Hill Energy Center SCR Retrofit

Location: Moberly, Mo.

Client: Associated Electric Cooperative Inc. (AECI)

Completion Date: December 2008

For this environmental controls retrofit project for Associated Electric Cooperative, Burns & McDonnell is providing detailed design and engineering for the retrofit selective catalytic reduction (SCR) systems for Units 1 (175 MW), 2 (295 MW) and 3 (715 MW). AECI faces tightening emission limits, so Burns & McDonnell was retained to develop a plan for compliance and to execute the plan. The multiple contract approach allowed AECI and Burns & McDonnell to work together to specify and select the best equipment while controlling project costs. The project includes new low NOx burners, new air heaters and modifications to the existing electrostatic precipitators on Unit 3.

  • Detailed design
  • Overall project management
  • Construction management
  • Studies of existing boiler, ductwork and electrostatic precipitator (ESP) design and draft system studies on each unit

The scope of work under the contract includes:

  • Detailed design of the SCR reactors, associated ductwork and foundations
  • Catalyst selection and supply
  • Flow model studies of ductwork design
  • Structural steel and ductwork design
  • Ammonia unloading, vaporization, dilution and injection grid design
  • Damper/seal air design
  • Design of popcorn ash screens at the outlet of the economizer ductwork
  • Catalyst cleaning system
  • Controls modifications to plant control system and burner management system for SCR operation
  • Modifications to plant electrical system to power SCR-related equipment
  • Balance of plant mechanical modifications to support the new systems

Construction for the project is being done under separate contract.

  • Selective catalytic reduction (SCR) system
  • Low NOx burners
  • New air heaters
  • Electrostatic precipitator (ESP) modifications