Coal Mine Ventilation Air Methane (VAM)

1
Coal Mine Ventilation Air Methane (VAM)
Project Development and Mitigation Options
Jayne Somers, Ph.D., P.E.US Environmental
Protection Agency 13th North American Mine
Ventilation Symposium Sudbury, Canada June 14,
2010
2
Presentation Overview

• Background on VAM Emissions
• U.S.VAM Data Summary
• Mitigation Technologies
• Oxidation Catalytic and Thermal
• Gas Turbines
• Hybrid Waste Coal/VAM Rotary Kiln

3
Global Recovery Utilization of CMM

• Degasification systems
• CMM drainage at active underground coal mines
  14 countries
• CMM recovery and utilization projects
• At active and/or abandoned (closed) coal mines
  13 countries
• 227 total CMM projects worldwide, 36 proposed or
  in development
• Avoided methane emissions gt 3.8 billion cubic
  meters annually (gt 54 MMTCO2E / yr)

4
Background on VAM

• Mine safety regulations require gassy
  underground coal mines to assure that methane
  concentrations in the mine workings are
  maintained at safe levels
• - Well below the lower explosive limit (5 in
  air)
• Mines employ large scale ventilation systems to
  vent methane to the atmosphere
• - Pre-mine drainage can supplement ventilation

5
Background on VAM

• Ventilation air methane (VAM) is largest source
  of coal mine methane (CMM) emissions
• - 54 of all U.S. CMM emissions in 2005
• Capturing and using VAM is challenging
• - Large airflows 100,000 to 1 million cfm (47 -
  470 m3/s)
• - Low concentrations range 0.1 to 1.0, often
  0.3 to 0.5
• Variable, both flow and concentration

6
Harnessing U.S. Ventilation Air Methane (VAM)

• Largest source of coal mine methane
• Low methane concentrations (lt1)
• Technologies emerging to harness ventilation air
  methane
• - As primary fuel
• - As secondary fuel

7
Summary of U.S. MSHA VAM Data

• Mines gt0.3 methane
• Quarterly sampling 2008-2009
• 39 mines with 78 exhausts
• 0.3 1.26 CH4

8
Global VAM emissions (2002)

• Emissions
• Country (Bm3) world
• China 6.7 38.7
• United States 2.6 15.0
• Ukraine 2.2 12.7
• Russia 0.7 4.0
• Australia 0.7 4.0
• Total World 17.3

9
Harnessing Ventilation Air Methane (VAM) (contd)

• As Supplemental Fuel at Appin-Tower Collieries
  (Australia)
• Installed in 1995
• 54 x 1 MW IC engines produce power from gob gas
• VAM used as feed air
• - supplied 7 of energy

10
VAM Oxidation Technologies

• Thermal Flow Reversal Reactors (TFRR)
• Commercial project MEGTEC Systems
• http//www.megtec.com
• Pilot project Biothermica http//www.biothe
  rmica.com

11
VAM Oxidation Technologies

• Durr Systems (Wisconsin, USA)
• Gulf Coast Environmental (Texas, USA)
• Sheng Dong Group (China)
• Catalytic Oxidizer CH4Min Prototype CANMET
  Energy Centre (Canada) http//www.nrcan.gc.ca/se
  /etb/cetc/cetc01/htmldocs/home_e.htm
• licensed by Sindicatum Carbon Capitol (SCC
  Americas)

12
Flow-reversal Oxidation Technology

• Schematic of an Oxidizer

Heat Exchange Medium
Valve 2
Valve 1
Heat Exchanger
Air C02, H20 Heat
Air CH4
Heat Exchange Medium
Valve 1
Valve 2
Valve 1 open Valve 2 open Heat recovery
piping not shown
13
MEGTEC Systems - VOCSIDIZER

• MEGTEC VOCSIDIZER
• 2007 Oxidation electricity generation, West
  Cliff Colliery, Australia
• 2007 Oxidation only Abandoned Windsor Mine
  (CONSOL Energy, West Liberty, West Virginia)
• 2008 Oxidation hot water, Zhengzhou, Henan,
  China
• 2010 Oxidation hot water, Datong, Chongqing,
  China

14
WestVAMP

• West Cliff Ventilation Air Methane Project
• Startup April 2007
• Capacity 250,000 m3/hour (150,000 scfm) of mine
  exhaust air
• VAM concentration 0.9 percent
• Generation unit steam turbine
• Electricity output 6 MW
• Four (4) VOCSIDIZER units (capturing 20 of VAM
  output)
• Ongoing project with two revenue sources
• - Electricity (over 80GWh generated)
• - Carbon credits from New South Wales trading
  scheme (over 500,000 traded)

15
WestVAMP
16
Zhengzhou, Henan, China

• First VAM project approved by UNFCCC under the
  CDM Mechanism
• Single VOCSIDIZER unit
• 0.3 - 0.7 CH4 concentration range

17
CONSOL Windsor Mine Demonstration

• Using diluted, drained CMM to simulate VAM
• Single MEGTEC VOCSIDIZER unit
• Operated unattended with a VAM concentration of
  0.6 percent
• Project partly funded by USEPA USDOE
• Goals were to verify
• - Ability to maintain VAM oxidation
• - System safety
• - Operability and maintenance with field
  conditions
• - Capacity 30,000 scfm of simulated VAM

18
CONSOL Windsor Mine Demonstration
19
Biothermica VAMOX

• Jim Walter Resources
• Brookwood, Alabama, USA
• Active Mine No. 7
• 2008 MSHA approval received
• 27,000 carbon credits in first year of operation
• Listed with the Climate Action Reserve (CAR)

20
Jim Walters Resources VAM Demonstration

• Single Biothermica VAMOX unit
• Capacity 30,000 cfm
• VAM concentration 0.9 percent
• Greenhouse gas emission mitigation gt35,000
  tonnes of CO2e per year
• Revenues Carbon emission reductions
• Projected lifetime gt 4 years

21
CONSOL McElroy Mine VAM Project

• Marshall County, West Virginia
• Verdeo Group is financing
• Registered with Climate Action Reserve
• Planned operation mid-2011

22
Gas Turbines

• Lean fuel gas turbine http//www.em.csiro.au/sust_
  mining/sustainable_projects.htmvamcat
• Microturbines
• Ingersol Rand Energy Systems http//energy.ingers
  ollrand.com/index_en.aspx
• FlexEnergy http//www.flexenergy.com/contactus.ht
  ml

23
CONSOL CMM-Fired Microturbine

• In early 2007, CONSOL Energy in partnership
  with Ingersoll Rand Energy Systems successfully
  demonstrated electricity generation by a
  microturbine fueled by unprocessed CMM at Bailey
  mine in Pennsylvania.
• The unit underwent a one-year operational phase.
• The 70 kW microturbine expected to generate
  approximately 500 MWh of electricity while
  consuming approximately 8 MMCF of methane that
  would have otherwise been emitted to the
  atmosphere.

24
Hybrid Coal Mine Gas Technology (HCGT)

• Combusts waste coal and VAM in a rotary kiln
• Generates thermal energy for electricity or steam
• Three 10 MW power plants were planned in India
  over the next five years
• EESTECH and Aryan Clean Coal Technologies joint
  venture http//www.eestechinc.com/index.php?page1
  6

25
Technology Deployment Benefits

• Ability to mitigate the largest source of coal
  mine emissions worldwide
• Capability to capture and beneficially use VAMs
  dilute energy content
• Adds to energy security by beneficially using a
  currently wasted energy source
• Multiple vendors should lead to cost competition
  that will drive down project capital costs
• Attractive payback times (3 - 6 years) can be
  achieved at VAM concentrations gt 0.6 percent and
  carbon emission reduction sale prices 10.00
  per tonne CO2e

26
Technology Deployment Challenges

• Newer technology field experience limited to a
  few countries
• Most VAM concentrations exiting the mine are
  below 1 percent
• May need supplemental methane (drained gas) to
  raise VAM inlet concentrations to near 1 percent

27
Conclusions

• Flow-reversal oxidation of VAM with power
  generation is a proven technology
• Field installations of various technologies are
  multiplying
• Potential global market for VAM-to-power
  applications is large
• Emerging cost competitiveness should enhance
  project economics

28
USEPA Coalbed Methane Outreach Program (CMOP)

• Voluntary climate change program since 1994
• Promote the profitable recovery and use of coal
  mine methane (CMM)
• Support CMM project development
• International Methane to Markets Partnership

29
Methane to Markets Partnership

• Encourages development of cost-effective methane
  recovery and use opportunities in
• coal mines
• landfills
• oil and gas systems and
• agriculture (manure waste management)
• Private companies, multilateral development banks
  and other relevant organizations participate by
  joining the Project Network over 900
  organizations now participating
• 34 Partner Governments

Japan Kazakhstan Korea Mexico Mongolia Nigeria Pak
istan Peru Philippines Poland Russia Thailand Ukra
ine United Kingdom United States Vietnam
Argentina Australia Brazil Bulgaria Canada Chile
China Colombia Dominican Republic European
Comm. Ecuador Finland Georgia Germany
India Italy
30
For more information, please contact us!

• Jayne Somers
• USEPA Climate Change Division
• somers.jayne_at_epa.gov
• 202-343-9896
• www.epa.gov/coalbed