Recently in Forestry Category
Southern Company has released a report detailing a series of tests conducted on co-firing green wood chips from whole and from approximately needle free pine trees. The purpose of the project was to "determine what level of processing of whole trees is required to successfully co-fire the chips in a boiler, and to evaluate the benefits and costs of wood processing compared with the effect of the fuel on the power plant." The tests were performed at Plant Gadsden in Gadsden, Alabama. From the report, summary results are as follows:
The full report can be found here.
- Green wood chips were successfully co-fired in blends with coal between 8% and 15%
wood by weight. Of the input fuel energy, 2.8% and 5.5% was from wood, and represented about 2.0 MW to 3.8 MW biomass power. - Sulfur emissions were reduced, and particulates were no higher with co-firing. At normal operating condition, carbon monoxide emissions were unchanged. The measured impact on NOx emissions was small.
- With 10% co-firing, boiler efficiency was about the same as coal alone, while there was a slight reduction in efficiency with 15% wood.
- Higher moisture losses due to high wood moisture were offset or nearly offset by reduced dry gas losses up the stack.
- High moisture of the wood coal mixtures resulted in low mill temperatures and high mill bowl under pressures. This caused a 5% load derate when co-firing 15%.
- The coal-wood mixtures had much lower fuel energy to volume ratio than the baseline coal. The issues appear to have been related to the installation of new automatic controls. Stability issues were corrected in subsequent tests by tuning the fuel-steam pressure automatic controls.
The full report can be found here.
Alabama's Gulf Coast Energy is ready to begin producing ethanol from waste wood as soon as next month. The demonstration plant will use gasification technology on wood waste and turn it into ethanol. The demonstration plant plans to eventually scale up to a commercial capacity of 45 million gallons per year. More information can be found here.
The first venture of the 2007 Chevron
Corporation and Weyerhaeuser Company partnership will be the development of Catchlight Energy LLC. The 50-50 venture is focused on the development of the next generation biofuels coming from non-food feedstocks. Catchlight Energy will "research and develop technology for converting cellulose-based biomass into economical, low-carbon biofuels." The full press release can be found here.