Release Date: July 3, 2001
|Terrestial Carbon Sequestration Test Underway
at Reclaimed Mine Site
DOE, TVA, EPRI Team to Use Coal Products to Enhance Nature's "Biological CO2 Scrubber" at Test Site in Kentucky
DRAKESBORO, KY - The U.S. Department of Energy has joined forces with the Tennessee Valley Authority and the Electric Power Research Institute to demonstrate what might be termed a "grassroots" approach to sequestering carbon dioxide. The new project will use coal combustion byproducts to enhance the storage of carbon in vegetation and soils.
A surface mine reclamation project at the 2,558-megawatt TVA-owned Paradise Fossil Plant near Drakesboro, Kentucky, is serving as the demonstration site.
Researchers plan to use the gypsum byproducts from the plant's flue gas scrubber to amend the soil and clarified wastewater from the plant to provide irrigation for vegetation. Both the soil and vegetation can act as "biological scrubbers" for carbon dioxide, offsetting a portion of the carbon emissions released when coal is burned in the power plant.
The scrubber byproducts will be applied as a mulch and should help increase the survival rate of native tree species and promote growth of vegetative ground cover. The alkaline nature of the scrubber material will also reduce acid runoff into local streams from the former mine site and provide cover and habitat for wildlife.
The project is an example of "terrestrial sequestration," one of several new approaches being studied by the Energy Department to reduce the buildup of gases in the atmosphere that can cause global warming.
The "whole plant" approach - a way of integrating several pollution prevention processes - could offer an economically attractive way for the power industry to meet future environmental goals, including the reduction of greenhouse gases.
At the Paradise site, new tree growth will increase the rate of carbon sequestration and provide new resources for the forest products industry. Properly conditioned, the soil can also serve as a "living membrane" to capture and retain carbon. The soil at the demonstration site currently has low carbon levels, but researchers believe that adding combustion by-products will increase the soil organic matter which, in turn, will improve nutrient absorption, water retention, resistence to erosion and over the long-term, the soil's ability to store carbon.
With the enhanced plant growth and improved soil conditions, the 100-acre demonstration site is expected to sequester between 60 to 80 metric tons of carbon over a 20-year period.
Managed by the DOE Office of Fossil Energy's National Energy Technology Laboratory, the project was initiated in October 2000 with the collection of soil samples and the receipt of water permits. Total project cost is nearly $1,3 million, including DOE's portion of $729,007.
The NETL Environmental Projects Division, working with TVA and EPRI, intends to complete the site environmental assessment, conduct greenhouse studies to determine the best plant species to use, develop recommendations for byproduct application and design a carbon capture and water emissions treatment system. TVA will construct the water treatment system.
|Contact: David Anna, DOE/NETL, 412-386-4646|