Grants and Contracts Details
Description
Due in part to the third lowest energy costs in the United States, the Commonwealth of Kentucky has a
concentration of high energy consuming industries. The reason for the low energy costs is the close
proximity of the utilities to the coal producing regions of the state, whose coal production is the nation's third
largest. According to the Office of Industrial Technologies in the U.S. Department of Energy (USDOE), the
Mining and Wood & Timber industries are two of seven industries that have been identified as consuming
the greatest amount of energy and both are major producers in Kentucky. The Timber industry is the largest
of any state east of the Mississippi River with a production of nearly 300 million feet boards of lumber
annually. Both industries produce a considerable amount of waste material that contains a significant
amount of energy. It is estimated that the coal operations current dispose 3 million tons annually of minus
100-mesh high energy (12,000 Btu/lb) coal due to cleaning, dewatering and handleability concerns. Despite
the ability to use the sawdust waste from lumber production as a industrial fuel, the eastern Kentucky
producers are forced to store approximately 100,000 tons on the surface of the lumber operations due to
modest heat values (3000 - 6000 Btu/Ib), high transportation costs and long haulage distances to industrial
sites.
The goal of the proposed project is to develop a premium fuel from the waste materials created from the
production of coal and lumber. The fine coal obtained from coal refuse ponds will be cleaned using advanced
separation technologies and then dewatered to lower moisture levels than currently realized by adding wood
fibers utilizing an enhanced dewatering technique. The clean coal and sawdust will be combined at a ratio of
about 90-to-1O and reconstituted (extruded or briquettes) to form a utility fuel that can be easily handled
through the transportation process. The close proximity of the two industries within the state minimizes
transportation costs. In fact, a lumber operator and a coal mining company having adjacent properties are
two of the cooperating partners in the proposed project. The project will be a joint effort between the
Kentucky Division of Energy, the University of Kentucky, two coal mining companies and two lumber
companies. The Kentucky Forrest Industries Association and an energy producer will also provide technical
advise during the 2-year duration of the proposed project.
In addition to improving the separation efficiency of fine coal recovery processes, the project proposes to
evaluate and optimize the use of sawdust during the upgrading of fine coal. Preliminary studies have shown
that the addition of sawdust and other wood fibers could reduce the moisture content of a dewatered filter
cake by an absolute 6 percentage points while also enhancing the strength of the briquettes formed from an
agglomeration process. Various wood types and their aging effects will be investigated in an effort to
understand the fundamental aspects of both the dewatering and briquetting process. The binder represents a
significant cost in the briquetting process for coal and it is believed that the quantity can be reduced by the
sawdust addition. However, to further enhance the economics, the concept of using all or a portion of the
binder amount to substitute for the chemicals used during cleaning and dewatering will be explored. A
previous study revealed that a tall oil derivative is an effective binder agent and tall oil is a well-known
additive in froth flotation, which is a commonly employed process for recovering fine coal.
After completion of the project tasks, a detailed economic evaluation of the total process will be conducted.
If proven favorable, the process will produce a fuel having an energy value of around 9000 - 10,000 Btu/lb
from material that is currently disposed in refuse ponds and landfills. The state would realize an annual
energy recovery of 842 billion Btu from sawdust while 69,600 billion Btu would be obtained from the fine
coal currently being disposed. Based on an average cost of 1.20 $/MMBtu, the total increased revenue
would be $84.5 million annually. Potential also exists for significant energy recovery from active or
abandoned refuse ponds. In addition to the energy gains, the use of wood as an energy source effectively
reduces CO2 emissions. Negative environmental aspects of surface disposal of sawdust and the increased life
of current refuse pond impoundments represent significant positive benefits resulting from the successful
completion of the proposed project.
Status | Finished |
---|---|
Effective start/end date | 7/1/02 → 6/30/05 |
Funding
- KY Natural Resources Environmental Protection Cabinet: $501,730.00
Fingerprint
Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.