Annual Meeting Preliminary Program - Full Brochure (PDF) - SME

TECHNICAL PROGRAM
differences in fossil energy resource endowment, technology maturity levels and
emerging national and regional regulations. The cost of CO2 emissions avoidance
with current technologies for capture is in the range of US $ 60 to 120 per
ton. In regions with abundant unconventional gas, such as the U.S., projected sustained
low natural gas prices have essentially driven new coal plants out of the
market. In China, in contrast, coal is still king and the emphasis is on the development
of super-critical and ultra-super critical coal plants to increase efficiency.
Both in the US, China and most of the rest of the world, there is also a rapid
growth in carbon capture and utilization (CCUS), with enhanced oil recovery
being seen as the dominant near-term market for use of the captured CO2. Still,
the market demand for CO2 is way below the emission rate on a global basis, requiring
long-term storage until renewable energy sources someday rule the roost.
4:05 PM
Coal in a Carbon-Constrained World with Ample Natural Gas
K. Lackner; Lenfest Center for Sustainable Energy, Columbia
University, New York, NY
Coal’s dominant role in electricity generation is challenged by two long-term developments.
First, natural gas availability is increasing and now seems assured for
a long time. Second, stabilizing carbon dioxide concentrations in the atmosphere
because of climate change concerns will result in severe restrictions on carbon
dioxide emission driving net world emissions gradually to zero. Without carbon
dioxide capture and storage technologies, the use of coal and ultimately of natural
gas is not limited by the size of the available resource but by the capacity of
the atmosphere to hold carbon dioxide as about half of the carbon dioxide will
remain in the atmosphere for centuries. We analyze the options for coal under
various scenarios and conclude that retrofitting old coal plants with carbon capture
technology is unlikely to be economic. For coal to survive requires significant
reductions in mining cost; new markets for coal, e.g. in the production of liquid
fuels; more options for carbon dioxide storage; and advanced energy conversion
technologies that combine high efficiency with integrated carbon dioxide capture
and storage.
coal & energy:
underground I
2:00 PM • Monday, February 25
chair: G. Buchan, Alpha Natural Resources,
Waynesburg, PA
2:00 PM
Introductions
2:05 PM
Numerical Analyses of Stability of Three-way and Four-way
Coal Mine Intersections in Illinois
B. Abbasi and Y. Chugh; Mining and Mineral Resources Engineering,
Southern Illinois University Carbondale, Carbondale, IL
Roof falls in Illinois are more likely to occur in mining intersection and this has
not changed in the last two decades. This research develops an improved scientific
understanding of stress distribution and failure behavior around 4-way and
3-way coal mine intersections. Three-dimensional numerical analyses were performed
to determine factors that influence intersection stability. The analyses
used a modified hardening/softening Hoek-Brown failure criterion. Yielded
zones around 3-way and 4-way intersections were developed. Intersection span
and horizontal stress have a major influence on intersection stability. For the 4-
way intersection, pillar corners across the intersection fail first and lead to progressive
failure of immediate roof and floor layers. The mechanism of failure is
similar for the 3-way entry but the shape and extension of yielded zones differ.
Coal ribs mostly fail due to tensile stress, while roof and floor strata fail due to
shear stresses. Rib corners fail due to a combination of shear and tensile stresses.
In addition to stress-based approach, displacement-based analyses were also performed
to delineate stability problems around intersections.
2:25 PM
Stress Distribution in Set-Up Rooms and Adjoining Areas for
Longwall Panels Oriented At Two Different Angles to In-Situ
Stress Orientation
B. Abbasi, Y. Chugh and H. Gurley; Mining and Mineral Resources
Engineering, Southern Illinois University Carbondale, Carbondale, IL
Design of stable set-up rooms and adjoining areas of a longwall face are critical
for safety and productivity. Illinois longwall faces have typically experienced
ground control problems in set-up rooms. Under a research project from the
State of Illinois over the last two years, the authors have successfully performed
field instrumentation studies and numerical analyses to improve design of set-up
rooms and adjoining areas. Some of these studies have been already published.
This paper presents a comparison of stress distribution in set-up rooms and in the
head gate and tail gate entries for a longwall face oriented in the E-W and N 28 E
orientations. The maximum compressive in-situ stress orientation in the area is
assumed to be N 70 E. The results indicate that the head gate entries for a longwall
face oriented N28E is subject to higher shear stress concentrations as compared
to a longwall face oriented E-W. This stress concentration area travels forward
as the longwall face is advanced. Therefore, additional supports should be
considered along the belt entry to ensure a stable and productive longwall face.
2:45 PM
Development of CISPM-MS and Its Applications in Assessing
Multi-Seam Mining Interactions
B. Qiu and Y. Luo; Mining Engineering, West Virginia University,
Morgantown, WV
Longwall and/or room-and-pillar mining operations in multiple coal seams
could not only induce subsurface and surface subsidence but also cause interactions
between these mined coal seams. The interaction might destabilize mine
structures and subsequently induce additional strata movements. Mechanical
models to utilize the predicted subsurface deformations to assess the interactions
and the consequences have been developed. The models are incorporated into a
computer program, CISPM-MS, for predicting the final surface movements and
deformations as well as the mining interactions associated with multi-seam coal
mining operations. It predicts final surface movements and deformations caused
by the individual mining operations and by the interactive effects. The program
can also be used to assess mine structural stability in multi-seam mining operations.
The paper presents the developed interaction models and their application
in surface subsidence prediction caused by multi-seam mining operations. A case
study involving mining in two coal seams, using longwall and room-and-pillar
mining methods, respectively, will be used to validate the program.
3:05 PM
Rationalize Drilling Control for Noise Reduction During Roof
Bolting Operation
Y. Luo 1 , B. Qiu 1 , C. Collins 2 and M. Li 1 ; 1 Mining Engineering,
West Virginia University, Morgantown, WV and 2 J.H. Fletcher
Mining Machinery, Huntington, WV
Roof bolter operators are a group of underground miners being exposed to high
doses of noise, especially when drilling hard rock. Previous research shows that
the specific energy of drilling decreases as bite depth (penetration per revolution
of drilling) increases. Less specific energy means less energy is wasted by producing
heat, bit wear and noise in the drilling process. This clearly implies that
proper control of drilling parameters provides an opportunity to reduce drilling
noise. Controlling noise from its sources can proactively reduce the noise exposure
to miners. Drilling tests have been conducted to prove this noise control
strategy. In the tests, noise levels are measured along with a number of other parameters.
The preliminary results show a noise reduction from 4 to 10 dB can be
achieved by drilling at a reasonably high bite depth in medium hard rock.
Applying this approach in drilling hard rock (e.g., sandstone) may expect even
better noise reduction. Based on the theoretical and experimental studies, rational
drilling control strategy could be developed for noise control while maintaining
a safe and productive roof bolting operation.
3:25 PM
Calibrated ALPS: Integrating Local Information into the ALPS
Pillar Design Approach
H. Lawson and J. Whyatt; Ground Control, NIOSH, Spokane, WA
The ALPS program has become a widely accepted tool for the design of pillars in
longwall coal mines. The current version of ALPS defines the critical stability
factor based on a national data base of case studies. The critical stability factor
This is the Technical Program as of September 1, 2012. IT IS SUBJECT TO CHANGE.
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Please see the Onsite Program for final details.