Abstract Booklet 2006 - Swanson School of Engineering - University ...

and pH. Additional elemental monitoring required by the WV Department of
Environmental Protection indicates that levels of As, Se, Ba, Cu, Pb, Ni and Hg are
below drinking water or aquatic life standards as appropriate indicating that the
benefits with respect to AMD remediation are not offset by the introduction of other
contaminants.
47-3
Environmental Concerns Related to the Use of Coal
Combustion By-products in Mine Placement
Tamara Vandivort, Paul F. Ziemkiewicz, WV Water Research Institute, USA
Earlier this year, the National Academy of Sciences Committee on Mine Placement of
Coal Combustion Wastes, released a report on Managing Coal Combustion Residues in
Mines. The Committee found placing coal combustion residues in mines to be a viable
way of disposing these materials as long as placement avoids adverse impacts to
human health and the environment. The Committee indicated advantages of doing so
including assisting with mine reclamation, lessening the need for new landfills, and
neutralizing acid mine drainage. The Committee recommended that minefills be
designed in such a way that water movement through the residues is minimized. This is
not based on any actual damage cases associated with minefilling, but on data on
environmental effects from surface impoundment and landfill sites which indicate that
adverse environmental impacts can occur when coal combustion residues have contact
with water or when the residues are not properly covered.
A U.S. Department of Energy - National Energy Technology Laboratory-funded
program, the Combustion Byproducts Recycling Consortium (CBRC), seeks to
promote and support the commercially viable and environmentally sound recycling of
CCBs for productive and sustainable uses of resources, through scientific research,
development, and field testing. Since its inception in 1998, the CBRC has funded 52
CCB research projects nationwide. Several of those projects include using CCBs in
mine filling, surface mine reclamation, and the mobility and control of metals in CCB
leachate. This paper will focus specifically on the projects related to using CCBs in
mining operations.
47-4
Influence of Residence Time on Fly Ash Leachability: Long-Term Implications
Gautham Das, Mark E. Hill, John L. Daniels, Vincent O. Ogunro, University of North
Carolina at Charlotte, USA
A considerable body of research has been conducted regarding the use of coal
combustion byproducts (CCBs) in general and leachability in particular. There are
many leach tests available as recommended by various agencies and described in the
open literature. Many of these have been used to characterize the leaching potential of
CCBs when considered for highvolume use in civil and highway engineering
applications. The majority of this work suggests that CCBs tend to leach various
constituents, often metals, boron, sulfates and chlorides, at concentrations above
applicable regulatory standards. However, in typical leaching tests, the leaching
solution composition, solid:liquid (L/S) ratio, residence time, temperature and level of
effective stress often has little in common with the field condition. As such, there is a
level of uncertainty regarding the true behavior of CCBs used as embankment or fill
material. This uncertainty tends to encourage disposal, even when all other technical
and financial constraints for reuse are met. As part of a broader research program to
better predict in situ performance of CCBs in construction, this paper reports on the
influence of pH and flowrate on fly ash leachate data. In particular, column
experiments were conducted at three levels of pH (4.3, 6.9 and 9.0) and at three
different flowrates (500, 1000 and 2000 mL/day). The results show differences in
conductivity, pH and Eh as the flowrate is increased. In general, these results suggest
that laboratory testing to determine field leachability should use flowrates similar to
that expected in situ. Such an approach has the added advantage of accounting for
time-dependent changes in mineralogy, which in turn dictate the chemical and physical
performance of CCBs.
47-5
A Business Opportunity in the Mid-Atlantic Highlands: An Environmentally
Sound and Cost Effective Solution for Filling Underground
Voids to Mitigate Hazards
John Jenkins, iLF Engineers, USA
Joseph F. Giacinto, Lenny G. Rafalko, Environmental Resources Management, Inc.,
USA
Paul Petzrick, Maryland Deparmtent of Natural Resources, USA
This paper outlines the sources and problems associated with abandoned mines, the
proximity of these mines to power plants producing CCPs and the beneficial utilization
of the CCPs to mitigate problems with abandoned underground mine lands. Coal
Combustion by-Products (CCPs), a waste product of coal fired power plants, have been
used for several years as material for subsurface void stabilization projects. CCP
material exhibits chemical reactions similar to commercially available Portland cement
when mixed with water and lime with dry strength properties more than sufficient to
support overlying rock strata and man made structures. Approximately 30 million tons
of CCPs are produced in close proximity to the 6,000 abandoned underground mines in
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the Mid-Atlantic Highlands. Lime sources required for pozzolan stabilized CCP
cement grout are plentiful throughout the Mid-Atlantic Highlands. CCP use in
subsurface void stabilization provides stowage for the continuous and voluminous CCP
waste stream in a beneficial, safe and environmentally benign manner to mitigate
hazards from abandoned underground mines common to the Mid-Atlantic Highlands.
Hazards from abandoned mines include subsidence, acidic water production, and
drastically disturbed hydrogeology. Abandoned mine hazards include subsidence (sink
holes) in addition to the release of radon gas and increased likelihood of groundwater
pollution. As a waste product, CCP material can be obtained for little to no cost. Using
CCP material presents an economic as well as an environmental incentive for large
volume grouting projects required of abandoned underground mine lands.
Through a cooperative effort of public and private sectors, the Maryland Power Plant
Research Project (PPRP) has developed a program to beneficially use CCPs in an
environmentally safe and effective manner. As a part of this program, PPRP developed
a cost optimization study to examine and minimize costs associated with CCP grouting
projects. This cost optimization evaluates the use of CCPs as subsurface void
stabilization and identifies the optimal means, methods, and associated budget costs to
transport, manage, mix, and inject CCP grout. Given the resources available in the
Mid-Atlantic Highlands, existing technology, the success of PPRP mine grouting
projects, and clearly demonstrated economical feasibility of using CCPs, a new
business opportunity exists in the Mid-Atlantic Highlands to restore thousands of
square miles of potentially hazardous real estate to productive use through subsurface
void stabilization.
SESSION 48
COAL PRODUCTION AND PREPARATION – 3
48-1
New Coals Collections. The First Results and Prospects
Svetlana A. Aiphtein, D.L. Shirochin, V.I. Minaev, Moscow State University of
Mining, RUSSIA
The new coals collection made of representative seems probes from Kuznetsk and
Donetsk basins are submitted. The collection consists of vitrinite coals with the
reflection index from 0.5 up to 1.5 %. Within the framework of similar rank, the coals
differing on facial conditions of primary coalification, chemical composition,
thermoplastic and physical properties are submitted. According to the Russian
classification these coals concern to different genetic types on a reducing degree. The
similar coals are allocated in the countries of Europe and the USA name «perhydrous
coals». The coal collection constantly replenishes and at the moment includes 22
samples. The coals have the full characteristic on technical, maceral and element
structure, on caking ability, on sorption and strength properties.
48-2
Application of Bacteria Thiobacillus Ferrooxidans by Desulphurization of Coal
Peter Fecko, Zuzana Sitavancova, Lukas Cvesper, Lukas Koval, VSB-TU Ostrava,
CZECH REPUBLIC
The aim of this paper is the suitability of bacterial leaching applied on the coal sample
from mine Most. The results of this work show that using clean cultures of
Thiobacillus ferroxidans is in the case very good if we evaluate desulphurisation from
point of view of pyrite sulphur, which, after one month of leaching is almost gone from
sample contains much organic sulphur which is produced by bacteria Thiobaicllus
ferrooxidans degraded only a little. Applying bacterial leaching it is possible to remove
approximately 36% of total sulphur and 32% of pyritic sulphur from the coal; better
results are obtained eliminating sulphate sulphur, i.e. up to 63% desulphurization and
desulphurization of organic sulphur is complicated; it fluctuates around 10%.
48-3
Clean Coal Technology for the Future - NEDO's Challenge
Shunichi Yanai, New Energy and Industrial Technology Development Organization,
JAPAN
Kyoichi Kohgami, Yusuke Tadakuma, Ichiro Fujiwara, Sadao Wasaka, NEDO,
JAPAN
In the paper, the activities of clean coal technology development by New Energy and
Industrial Technology Development Organization (NEDO), Japan are introduced.
We have three main projects as follows; 1) a high efficiency coal gasification
technology development (EAGLE), 2) ash-free coal production technology
development (Hyper-coal), and 3) clean fuel production technology development from
asphalt (ATL). In the EAGLE project, a gasifier, that can produce multi-purpose coal
derived synthesis gas efficiently, has been developed. The features of the gasifier are
that it has high efficiency and wide variety of coals is acceptable in the gasifier. The
progress of the development is explained in the paper. Hyper-coal is a challenging
technology development project, that produces completely ash-free coal (less than
200ppm) by the solvent de-ashing technology. In the paper, the progress of its
technology and its applications are introduced. ATL stands for Asphalt To Liquids.