The stack at Deer Creek Station was topped out on Aug. 1. Work started on the stack toward the end of 2010. Work continues, including electricial and instrumentation, paint, and other structural work.
The stack is 150 feet high and is constructed using 15 “ring sections,” which are made of carbon steel. Each section is almost 10 feet in height and each section weighs differently because of the decreasing wall thickness from the base to the top of the stack.
The final section of stack is set at the Deer Creek Station site.
Deer Creek Station is a 300-net megawatt natural gas combined-cycle generation facility. The plant features two turbine-generator sets: one turbine fired by natural gas; the other is driven by steam. Both of the turbines are connected to generators.
Gary Hager, Basin Electric mechanical field engineer on site, says the Deer Creek Station stack is different from coal-based power plant stacks. “Most of the other stacks are composed of some type of reinforced concrete or refractory, with a stack liner for discharge of the flue gas. Because of the design and operation of the boilers in coal-based facilities, the stacks are much taller than the stack at Deer Creek Station,” he says.
Hager says a coal-based power plant’s stack is much taller because of the flue gas’ flow rate, temperature, desired stack effect, and flue gas buoyancy. “For example, the new stack at Leland Olds Station, from ground to top of fiberglass liner, is roughly 600 feet. The stack at Deer Creek Station is only 150 feet.”
