The Illinois Environmental Protection Agency is taking comment until Feb. 23 on a draft air permit change being sought by Eastern Illinois University (EIU) for its new Renewable Energy Center.
The construction permit for the center was originally issued in November 2009. This facility supplies steam for heating and cooling university buildings. It replaced EIU’s old steam plant that used coal as its principal fuel. The requested revision would: adjust the permitted capacities of the gasifier-boiler units; adjust various permit limits for emissions of NOX and other pollutants to address the results of initial operational and emission testing of the units; and make other related changes to the permit. The Energy Center began operation in the summer of 2011.
The Energy Center has two gasifier-boiler units that are fired with biomass. The principal fuel is chipped wood and bark, obtained from forestry, lumber production and tree trimming operations. The first part of each gasifier-boiler unit, the gasifier, processes the biomass fuel or feedstock to produce a hot fuel gas. This fuel gas is mixed with additional air and combustion is carried to completion in a separate combustion chamber. The hot combustion gases pass to a boiler in which the thermal energy of the hot gases is recovered as steam.
The Energy Center also has two natural gas/oil fired boilers. Natural gas is the primary fuel for these boilers. Distillate oil is a backup fuel.