Tour includes examination of boiler that will burn cobs
WILLMAR -- Three recently appointed Willmar Municipal Utilities commissioners were pleased after touring the utility's downtown power plant for the first time on Monday.
Matt Schrupp, whose three-year term began in January, said he was surprised by the size and the magnitude of the equipment.
"I wasn't aware of the size of the boilers. They are a lot larger than I expected to see. I got a better understanding of the type of equipment and the processes involved,'' Schrupp said.
Steve Salzer, whose term began in February 2008, said he was interested to see how coal was fed into the boilers and how it will tie into the anticipated test burn of corn cobs as a renewable fuel, in addition to coal.
Gary Myhre, a member since September 2008, said he was also interested in how the corn cobs will be injected into the boilers. "I'm interested in seeing that for some biofuel alternatives,'' he said.
The new commissioners had asked utility officials for a tour of the plant as part of an effort to become familiar with utility facilities. The tour took place after the regular Monday meeting.
Jeff Kimpling, manager of electric services, said a tour is scheduled for March 23 of the water purification plants, the electric substations, the wastewater treatment plant, the service center, and the corn cob storage site and site for the utility's two new wind turbines.
Schrupp, Salzer and Myhre, along with Commissioner Marv Kray and Jim Dokken, alternate City Council liaison to the utilities commission, were led on the tour by Ken Nash, power production superintendent.
According to the utility's centennial history, published in October 1991, the city's first light plant was built in 1895 on Block 42, which is the present site of Christianson and Associates.
The plant was rebuilt in 1901 following an explosion. In 1925, new electrical generation equipment was installed at the present power plant site and a major addition to the plant was constructed in 1949. A new steam boiler was installed in 1961 and a new turbine was installed in 1970.
Among other things, the group saw how the coal-handling equipment feeds the coal from the storage silos and into boiler No. 3, the plant's main boiler in which the corn cobs will be burned -- if the utility receives an air quality permit from the Minnesota Pollution Control Agency. Officials believe they'll be receiving the permit soon.
Nash said mechanized stokers throw the coal onto the fire box grate, which moves slowly to the front where the ash is dropped off. Below the stokers are access doors where the fireman is able to look inside and see how the fire is burning or watch the ash come off. Nash said numerous things can go wrong with the combustion.
With the aid of a special glass, commissioners looked inside the boiler through an observation port. Nash said the glass enables the fireman to see what the flame looks like. Without the glass, the brightness of the burning fire obscures the flame. By observing the flame, fireman Joe Baker can determine if the fire should be "longer or shorter,'' Nash said.
In the control room, plant operator Brian Hoover was monitoring the operation of the plant and the city's electrical system. The plant has an operator and a boiler fireman on duty at all times, Nash said.
The power plant, along with the diesel generating units at the southwest and east substation, are capable of generating about 35 of the city's peak of 60 or more megawatts of electricity, according to Nash. The plant also provides hot water for the district heating system.
Although the plant is old, it has been well-maintained, Nash said. He said many cities quit generating their own power since the 1970s when it was easier to buy electricity. He said the future of the plant looks good.
"Places like this become, I think, a lot more valuable especially if they've been maintained as well and are still able to run,'' said Nash.
"I think with the biomass and the mandate from the state to burn 25 percent renewables by 2025 and we're building a couple of wind turbines and we're starting this experiment with corn cobs, I'm excited that it looks good for here,'' he said.