UMM biomass plant running according to plan
By Tom Larson
The day appears near when the University of Minnesota, Morris will have its biomass gasification system ready to heat and cool a large portion of its campus buildings.
Experiments with fuel densities, which had occupied plant researchers efforts for months, apparently have paid dividends: wisps of smoke were coming from the plant's stack.
Lowell Rasmussen, UMM's Vice Chancellor for Finance and Facilities, said that test burns last week using wood chips and corn stover have proved successful.
The burner was firing for 120 consecutive hours until it was shut down for more analysis last Thursday. The plant could be in full use this fall, about two years after officials had originally planned.
"We're really happy with the results," Rasmussen said. "For the next couple of weeks we'll be doing our homework."
The biomass gasification system, the first of its kind, is a component of UMM's goal of carbon neutrality by this year, and it is expected, when operating at peak efficiency, to produce 80 percent of the energy needed for campus heating and cooling.
UMM and the boiler manufacturer, English Boiler, had worked to modify the boiler when it proved more difficult than anticipated to burn biofuels instead of conventional fuels because the biofuels combust so much faster, Rasmussen said.
The answer came in the form of compressed biomass "logs" that are crumbled and then gasified to produce "syngas" to replace natural gas. The syngas is then burned to produce steam used in the university's heating and cooling systems.
"It was not so much the machine as it was how we're operating the machine," Rasmussen said.
Compressing the biomass also reduces energy loss that occurs when it's in a loose form and decomposed.
The $9 million project is intended to offset UMM's fossil fuel needs and help the university meet its goal of being energy self-sufficient and carbon neutral. by 2010.
A Walking Trailer moves the stover into the burner, where air is blown through from the bottom of the burner for combustion.
Most solid fuel gasifiers burn heavy density wood at a temperature of about 3,000 degrees, and the ash produced can only be used for limited purposes, such as wallboard.
UMM's goal is to create the first gasifier that incinerates the fuel temperatures of 1,000 degrees or lower, producing gas that can be used to create steam for UMM's system while also preserving minerals in the ash so it can be used in soils.
Rasmussen said that if the new fuel stock works well, it could create business opportunities in the area.
Despite the setbacks, interest in the technology and the process remains high. There are about $4 million worth of grants from federal and state agencies and individual patrons waiting on the research, Rasmussen said.
Testing will continue this summer and the system is expected to be in full operation this fall, he said.
"The thing that makes us say, 'Let's keep working on this' is that the lessons we learned will help people in other communities make use of this. I think that's part of our land grant legacy."