Pre-feasibility Study for Coal Mine Methane Drainage and Utilization at the Kozlu Coal Mine in Zonguldak, Turkey March 2015


U.S. EPA

Coalbed Methane

OUTREACH PROGRAM

$
s

33

V

&

PRQt^0

"6

z

UJ

(D
X

Pre-feasibility Study for Coal Mine Methane
Drainage and Ut lization at the Kozlu Coal
Mine n Zonguldak, Turkey

*>'¦

r- -J

..it %

Wmm

-------
Pre-feasibility Study for Coal Mine Methane Drainage and
Utilization at the Kozlu Coal Mine in Zonguldak, Turkey

# O \

w

PRO"^

Sponsored by:

U.S. Environmental Protection Agency, Washington, DC USA

Prepared by:

Eastern Research Group
HEL-East Ltd.

Ruby Canyon Engineering Inc.

March 2015

-------
Acknowledgements

This report was prepared by Eastern Research Group (ERG) at the request of the United States
Environmental Protection Agency (USEPA), in support of the Global Methane Initiative (GMI). In
collaboration with the Coalbed Methane Outreach Program (CMOP), the principal authors of the report
are Ronald Collings and Michael Cote with Ruby Canyon Engineering (RCE); Neil Butler with Harworth
East Limited (HEL); Brian Guzzone and Brooke Leigh Robel with Eastern Research Group (ERG); Dr.
Abdullah Fisnewith Istanbul Technical University; C. Ozgen Karacan with National Institute for
Occupational Safety and Health; and Dr. Satya Harpalani with Southern Illinois University.

Disclaimer

This report was prepared for USEPA. This analysis uses publicly available information in combination
with information obtained through direct contact with mine personnel, equipment vendors, and project
developers. USEPA does not:

(a)	make any warranty or representation, expressed or impliedwith respect to the accuracy,
completeness, or usefulness of the information contained in this report, or that the use of any apparatus,
method, or process disclosed in this report may not infringe upon privately owned rights;

(b)	assume any liability with respect to the use of, or damages resulting from the use of, any information,
apparatus, method, or process disclosed in this report; or

(c)	imply endorsement of any technology supplier, product, or process mentioned in this report.

-------
Table of Contents

Acronyms and Abbreviations	i

Tables and Figures	ii

I.0	Executive Summary	3

1.1 Observations and Recommendations	4

2.0 Background	6

3.0 Summary of Mine Characteristics	9

3.1	Geologic Setting	9

3.2	Coal Characteristics	11

3.3	Coal Production	11

3.4	Coal Reserves	13

4.0 Gas Resources Assessment	13

5.0 Gas Outburst Characterization at TTK	15

6.0 Outburst Control Leading to CMM Capture and Utilization	20

6.1	Drilling Equipment	20

6.2	Outburst System Design	21

6.3	Gas Drainage System	21

6.4	Management Processes	21

6.5	Methodology and Estimated Cost for Improvement of Outburst Control	21

7.0 Energy Market Information	22

7.1 Carbon Market Participation	25

8.0 End Use Assessment	25

8.1 VAM Power Economics	26

9.0 Observations and Recommendations	27

10.0 Conclusions	28

II.0	References	29

-------
Acronyms and Abbreviations

Btu	British thermal unit

C	Celsius

Bern	Billion cubic meters

CAPEX	capital expenditure

CBM	coalbed methane

CER	Certified Emission Reduction

CH4	methane

CMM	coal mine methane

CMOP	Coalbed Methane Outreach Program

C02	carbon dioxide

C02e	carbon dioxide equivalent

GHG	greenhouse gas

GMI	Global Methane Initiative

IRR	internal rate of return

kcal	kilocalorie

kg	kilogram

km	kilometer

M	million

m3	cubic meter

Mcf	million cubic feet

MJ/m3	million joules per cubic meter

mm	millimeter

Mt	million tonnes

MW	megawatt

MWe	megawatt electrical power

MWhr	megawatt hour

MWth	megawatt thermal power

NPV	net present value

t	tonne

tC02e	metric tons of carbon dioxide equivalent

tonne	metric ton

VAM	ventilation air methane

VER	verified emission reduction

i

-------
Tables and Figures

Table 1: Coal rank by mine	11

Table 2: Coal produced from 1970 through 2012 and remaining reserves by category, million tonnes... 13
Table 3: Average depth of measured sample, number of samples and comparison of measured gas

content and specific emissions	14

Table 4: Historical mining rate and specific emissions used to estimate future mine emissions and

potential power generation assuming 25% emissions capture at usable quality	15

Table 5: Largest outburst events in the Kozlu and Karadon mines	18

Table 6: Kozlu high, low, and average measured gas content by seam	19

Table 7: Karadon high, low, and average measured gas content by seam	20

Table 8: Summary of estimated costs for improvement of outburst control	22

Table 9: Turkey half-yearly electricity and gas prices	25

Table 10: Capital and operating and maintenance costs for low and high efficiency power production

from VAM oxidation	26

Table 11: Economic results for high efficiency VAM power unit	27

Table 12: Economic results for low efficiency VAM power unit	27

Figure 1: Location of Turkey's coal resources by type	7

Figure 2: Location of the TTK coal concession, active mines, and city of Zonguldak	7

Figure 3: Location of the Kozlu mine and ventilation shaft	8

Figure 4: Generalized stratigraphic section of the Zonguldak Coal Basin	9

Figure 5: Geological map of Zonguldak Coal Basin, Turkey	10

Figure 6: Diagrammatic geologic structural cross-section of Zonguldak mining area	11

Figure 7: Yearly coal production for TTK mines in Zonguldak coal basin	12

Figure 8: Average depth of mining from 1941 to 2013 in meters from sea level for the TTK mines	13

Figure 9: Specific emissions by mine from 1970	14

Figure 10: Outburst frequency and occurrence rate relative to tonnes coal mined	16

Figure 11: Frequency distribution of locations of outbursts occurred in Kozlu and Karadon Collieries in

Zonguldak Coal Basin	17

Figure 12: Outburst frequency relative to the distance from a known fault	17

Figure 13: Outburst frequency by coal seam for both the Kozlu and Karadon mines	19

Figure 14: Turkey's total primary energy	22

Figure 15: Turkey coal production	23

Figure 16: Turkey's natural gas consumption vs. production	24

Figure 17: Power generation by sector for Turkey in 2011	24

ii

-------
1.0 Executive Summary

As part of its commitment to support the Global Methane Initiative (GMI), the U.S. Environmental
Protection Agency's (USEPA's) Coalbed Methane Outreach Program (CMOP) commissioned a pre-
feasibility study to examine the potential for a coal mine methane (CMM) recovery and utilization
project at the Kozlu underground coal mine in Zonguldak, Turkey. GMI is a voluntary, multilateral
partnership that aims to reduce global methane (CH4) emissions and to advance the abatement,
recovery, and use of methane as a valuable clean energy source. GMI achieves its goals by creating an
international network of partner governments, private sector members, development banks,
universities, and non-governmental organizations in order to build capacity, develop strategies and
markets, and remove barriers to project development for methane reduction, including CMM in Partner
Countries. Turkey joined the Initiative in 2010 to improve mine safety to prevent explosions and to
recover and use methane from coal mines. More information about Turkey's coal mining sector can be
found at https://www.globalmethane.org/documents/toolsres coal overview ch33.pdf as well as
https://www.globalmethane.org/documents/coal cap turkey.pdf. More information about GMI and
coal sector activities can be found at www.globalmethane.org.

Turkey's coal mining industry is dominated by two state-owned companies: Turkish Coal Enterprises
(TKI) and Turkish Hardcoal Enterprises (TTK). TKI mines the country's estimated reserves of 11.6 billion
tonnes of low quality lignite coals while TTK mines the estimated reserves of 1.3 billion tonnes of
bituminous, coking, and non-coking coal in five active mines.

Turkey's hard coal resource is restricted to a relatively small area along its northwest coast of the Black
Sea. The coal measures are composed of numerous seams with high gas content. Mining conditions are
extremely difficult because of intense faulting and folding of the strata with inclinations of up to 90
degrees. The Zonguldak coal basin contains Upper Carboniferous bituminous coal, including the Kozlu
formation. There are more than 20 coal seams within the Kozlu formation. Net coal thickness for this
stratigraphic sequence ranges from 30 to 32 meters across the Kozlu region. The calorific value for coals
in the basin range from 6,200 to 7,250 kilocalories per kilogram of coal (kcal/kg).

The strata have been tectonically disturbed, resulting in significant faulting and folding. The mined
seams can have a dip from 0 degrees to 90 degrees, making mining conditions very difficult and
precluding the use of mechanized coal mining equipment. Instead, labor intensive methods are in use.
The coal is also prone to spontaneous combustion, adding to the already difficult mining conditions
imposed by the structural complexity of the geology.

Kozlu is one of the deepest mines at about -500 meters and significant reserves remain for many
decades of coal production, with the possibility of mining below -1000 meters in the future. TTK
management expects the trend of mining deeper levels will continue. Under current practices, the
number and severity of outbursts will increase as will methane emissions at the coal face as mining at
deeper levels occur. Although coal production is declining, infrastructure projects including gallery and

-------
deep shaft development are underway with the goal of increasing production to 5 million tonnes per
year from UK's five mines.

In-situ gas content has been measured at all of the TTK mines. The Kozlu mine is among the deepest and
has correspondingly higher measured and specific emissions: approximate average gas content of 9.07
cubic meters per tonne (m3/tonne), average specific emissions of 20.94 m3/tonne mined.

Two of the five active TTK mines—Karadon and Kozlu—have severe coal outburst problems that disrupt
mining and cause injury or death to miners. TTK management determined that control of the coal
outburst problems is a top priority.

Current practices at the Kozlu coal mine to control outbursts have proven inadequate. There is no gas
drainage system in place (i.e., vented in the mine workings); the design of the outburst control system is
insufficient because the drill cannot reach the end of the heading development; and the drilling
equipment cannot drill far enough ahead to enable outbursts to be located, discharged, and drained
(current limit is 25 meters). The limited reach of the drilling equipment means that outburst control
techniques and corresponding management processes will continue to be ineffective.

Based on the meeting with TTK in September 2013, and a preliminary analysis of the information
gathered during the site visit and thereafter, the Kozlu coal mine was selected for this pre-feasibility
study (e.g., TTK's gassiest mine, opportunities for controlling outbursts). The pre-feasibility study focuses
on developing recommendations to reduce methane gas outbursts in the Kozlu mine and evaluating the
potential to capture methane for utilization.

Observations and Recommendations

The study finds that before a methane capture and utilization project is considered, coal outburst
control should be prioritized and additional information should be gathered and analyzed to reduce
uncertainty and provide a sound basis for investment. After making improvements to control coal
outbursts, the mine should be further evaluated to determine specific opportunities for CMM recovery
and use (see Section 8.0 for initial potential end use options).

To prevent frequent outbursts and resulting injuries or fatalities at Kozlu, the following approach for
improving safety and operations within the mine is recommended (see Section 6.0 for additional
details):

• Generate a budget for improved equipment and procedures for outburst control.

• Procure new lightweight powerful in-mine drilling rigs with high quality rods and bits that have
the capacity to drill 60 to 100 meters and train personnel on usage of the equipment.

• Design and install a new methane drainage pipework system in the mine capable of extracting
gas/dust away from the drill hole and then away to the outside of the mine.

• Install a new methane extraction plant (a suitable vacuum pumping station design is available).

• Develop a new outburst control design and implementation protocol (incorporating the new
drilling system and training for operators, methane drainage pipework, and methane extraction
plant).

-------
• Develop new outburst management processes that correspond to the new equipment and
drainage design and procedures.

• Once these outburst control recommendations are established, drainage volumes and gas
quality should be monitored to determine the feasibility of establishing a technically and
economically feasible end use technology for the mine methane.

Budget costs for recommendation #2 (procuring new drilling equipment) are expected to be
approximately USD$300,000 for the Kozlu mine. After demonstrating that the drilling equipment
performs as recommended, it would then be appropriate (in a staged sequence) to install underground
pipes. The cost of the underground pipes is entirely dependent on distance to mine shaft and pipe
diameter/material, but the cost would be in the range of $100,000 to $500,000. Once the pipework is
installed and the gas is discharged on the surface, a methane extraction plant should be installed
(estimated cost $350,000). The total budget for implementing the recommendations for the Kozlu mine,
including external drainage design consultants and all equipment, training, and on the job practical
instruction, would be approximately $1 million phased in over the course of two years.

Although the Kozlu mine is gassy, factors such as low gas permeability, the fractured nature of the coal
geology, and the low, non-mechanized production rates mean that CMM pre- or post-drainage
techniques for methane capture during production are likely to be unsuccessful (distinctly separate from
outburst control). At this time, outburst control should be a primary priority for TTK.

In the first phase of improved outburst control, the outbursts of gas will be encountered intermittently,
and there will not be continuous CMM gas flow available which would be suitable for utilization. With
the establishment of the improved drilling, gas gathering and extraction pump systems in place to
capture and safely remove the outburst gas, drainage volumes and gas quality can be monitored to
determine the feasibility of establishing a profitable end use technology for the mine methane.

Several CMM capture and utilization options were evaluated for this study. At this time, because of the
intermittent drainage gas flow, the only technically and commercially viable option for methane
utilization is VAM to power, using regenerative thermal oxidizers (RTO) coupled to waste heat recovery
boilers and a steam turbine. The average methane concentration at the main mine ventilation shaft is
>0.6 percent methane; therefore, there is sufficient heat energy in the gas to maintain self-sustaining
operation of the RTOs and deliver excess heat via the hot gas bypasses (from each RTO) into a boiler and
then to a superheater connected to an impulse steam turbine. Typical net cycle efficiency is in the range
of 18 to 28 percent, depending on design of the RTO, boiler, and steam turbine. Steam turbine
manufacturing period is in the 9 to 12 month range, therefore the project would have a 12 to 14 month
implementation period. It would also be possible to explore the use of RTOs interconnected to an
Organic Rankine Cycle generator or a Rotary Screw generator. These technologies are lower efficiency at
around 15 percent net cycle efficiency.

To develop this project, the high capital investment would demand a long term power purchase
agreement from the coal mine to buy the electricity, and possibly revenue from carbon credits.

-------
2.0 Background

As part of its commitment to support the Global Methane Initiative (GMI), the U.S. Environmental
Protection Agency's (USEPA's) Coalbed Methane Outreach Program (CMOP) commissioned a pre-
feasibility study to examine the potential for a coal mine methane (CMM) recovery and utilization
project at Kozlu coal mine in Zonguldak, Turkey. GMI is a voluntary, multilateral partnership that aims to
reduce global methane (CH4) emissions and to advance the abatement, recovery, and use of methane as
a valuable clean energy source. GMI achieves its goals by creating an international network of partner
governments, private sector members, development banks, universities, and non-governmental
organizations in order to build capacity, develop strategies and markets, and remove barriers to project
development for methane reduction, including CMM in Partner Countries. Turkey joined the Initiative in
2010 to improve mine safety to prevent explosions and to recover and use methane from coal mines.
More information about Turkey's coal mining sector can be found at
https://www.globalmethane.org/documents/toolsres coal overview ch33.pdf as well as
https://www.globalmethane.org/documents/coal cap turkey.pdf. More information about GMI and
coal sector activities can be found at www.globalmethane.org.

TKI mines the country's estimated reserves of 11.6 billion tonnes of low-quality lignite coals
(approximately 2.5 billion tonnes) while TTK mines the estimated reserves of 1.3 billion tonnes of
bituminous, coking, and non-coking coal in five active mines in the Zonguldak basin. Figure 1 shows the
location of Turkey's coal resource areas. While there are some methane emission problems in TKI mines,
they are unusual in that the source does not appear to come from the lignite itself, which has very low
native methane content, but from other as yet indeterminate sources. This issue is currently being
addressed by a Turkish administered public-private partnership to determine the gas source and to drain
and utilize the gas so that mine safety is maintained. In contrast, the carboniferous age bituminous coals
of the TTK mines have numerous seams of high gas content but low permeability coal. Two of the five
active TTK mines—Karadon and Kozlu—have documented severe coal outburst problems that disrupt
mining and have caused injuries and deaths.

Following initial communication with TTK management, the project team visited Zonguldak on Turkey's
northwest coast in September 2013. As shown in Figure 2, Zonguldak is the location of TTK's
headquarters and their five active mines. Of the five TTK-operated mines, the Kozlu and Karadon mines
are of the greatest concern to TTK because they are the gassiest underground mines and have the
greatest number of gas outbursts. While TTK has targeted and attempted to drain high pressure gas
buildup prior to mining, their efforts to date have not been successful. Figure 3 shows the location of
the Kozlu mine and ventilation shaft.

-------
Figure 1: Location of Turkey's coal resources by type1

HEMA
Greenfield Site

Trak

Zonguldak^ Mengen
• Istanbul

TTK

Active Hard Coal

Orhanoli Ke

, Ankara

ajf /

w

r uk11

AMASRA COLLIERY

	N J

KARADON COLLIERY

UZULMEZ COLL

KOZLU
COLLIERY

Under sea
3000 km2

1 Virginia Polytechnic Institute and State University (Virginia Tech) Virginia Center for Coal & Energy Research
(2012)

Okten et al (2011)

7

-------
Figure 3: Location of the Kozlu mine and ventilation shaft

There is no pre- or post-mining drainage system currently in place at either mine (i.e., gas is vented in
the mine workings).

Kozlu is the gassiest in terms of gas content and emissions per tonne of coal mined. The mine produces
approximately 2,000 tonnes per day of coal and exhausts approximately 1.83 billion cubic feet per day
(Bcf/d) or 51,826 nr/day of methane using two exhaust fans. Typical concentration of methane at the
main mine ventilation shaft is >0.6% methane.

Based on the meeting with TTK in September 2013, and a preliminary analysis of the information
gathered during the site visit and thereafter, the Kozlu coal mine was selected for this pre-feasibility
study (e.g., TTK's gassiest mine, opportunities for controlling outbursts). The study focuses on
developing recommendations to reduce methane gas outbursts in the Kozlu mine and evaluating the
potential to capture methane for utilization.

Virginia Polytechnic Institute and State University (Virginia Tech) Virginia Center for Coal & Energy Research
(2012)

8

-------
3.0 Summary of Mine Characteristics

3.1 Geologic Setting

The Zonguldak coal basin contains Upper Carboniferous bituminous coal. The coal is located within a
deltaic sedimentary sequence of Westphalian-A age. The coal-bearing sequence of Zonguldak basin
contains the Namurien Alacaagzi Formation, Westphalian A Kozlu Formation, and Westphalian B-D
Karadon Formation. Westphalian-A aged Kozlu Formation is formed by interbedded sandstones,
siltstones, mudstones, conglomerates, and coals. The overlying Westphalian B-D aged Karadon
Formation has a similar succession as the Kozlu formation, but has fewer coal seams. There are more
than 20 coal seams within the Kozlu formation. Net coal thickness for this stratigraphic sequence ranges
from 30 to 32 meters across the Kozlu region. Figure 4 shows a generalized stratigraphic section for
Zonguldak Coal Basin.

Figure 4: Generalized stratigraphic section of the Zonguldak Coal Basin4

Toprak, S. (2009)

9

-------
The strata have been tectonically disturbed, resulting in significant faulting and folding. The mined
seams can have a dip from 0 degrees to 90 degrees, making mining conditions very difficult and
precluding the use of mechanized coal mining equipment. Figure 5 shows a geological map of the basin
and Figure 6 shows a geologic cross-section.

Figure 5: Geological map of Zonguldak Coal Basin, Turkey5

Post Carboniferous

Karadon Fm. (Westpholiqn B,C,D)	' I ^ 11^

Kozlu Fm. (Wesfphalian A)	ZONGULDAK AREA

Alacaajzi Fm. (Namurian)	Faults

I o I 2 3km

» '

Yilonli Fm. ( Vlscon )	^ Towns

Hosgormez, H. (2007)

10

-------
Figure 6: Diagrammatic geologic structural cross-section of Zonguldak mining area6

The calorific value for coals in the basin range from 6200 to 7250 kcal/kg. Table 1 shows the coal rank by
mine. The coal is also prone to spontaneous combustion, adding to the already difficult mining
conditions imposed by the geology's structural complexity.

Table 1: Coal rank by mine7



Co

liery

Armutfuk

Amasra

Kozlu - Uzulmez

Karadon

ISO Code
Number

622

711

533-534

534

ISO Class

VIA

VII

VC-VD

VC

Cokeability

Medium/Weak

Very Weak

Medium/Well

Very Well

ASTM Rank
Scale

62-148

58-139

68-154

69-155

ASTM Rank
Class

n-it

ll-Bt

ll-Bt

II Bt

ASTM Rank
Group

Hv Ab

Hv Bb

HV Ab

HV Ab

3.3 Coal Production

Because of the difficult mining conditions imposed by the geology's structural complexity, mechanized
mining methods cannot be used. Instead, labor intensive methods are in use (e.g., retreating short wall

6	Ozturk, M. (2013a)

7	Ozturk, M. (2013b)

11

-------
method with back caving is common). The high pressure air breaking method is used in the steep coal
seams with a dip greater than 45 degrees and a seam thickness greater than two meters. Saleable
production is approximately 80% of mine production.

Although coal production is declining, infrastructure projects including gallery and deep shaft
development are underway with the goal of increasing production to 5 million tonnes per year from
UK's five mines (Figure 7). TTK has also opened approximately 40% of its resources to private sector
miners under a royalty agreement. Currently, the private sector companies are producing about
1 million tonnes per year, but are expected to increase production to 5 million tonnes per year in the
midterm.

Figure 7: Yearly coal production for TTK mines in Zonguldak coal basin8

3,500,000
3,000,000

$ 2,500,000
>-

1970 1975 1980 1985 1990 1995 2000 2005 2010
•Kozlu	Ka radon	Armutcuk	Amasra	Uzulmez

Depth of mining has increased through time as shown in Figure 8. Currently, Armutcuk and Kozlu are the
deepest at about -500 meters with Karadon at about -350 meters. At the Kozlu mine, significant reserves
remain for many decades of coal production with the possibility of mining below -1000 meters in the
future. TTK management expects the trend of mining deeper levels will continue. Under current
practices, the number and severity of outbursts will increase as will methane emissions at the coal face
as mining at deeper levels occurs.

8 Ozturk, M. (2013a)

12

-------
Figure 8: Average depth of mining from 1941 to 2013 in meters from sea level for the TTK mines9

3.4 Coal Reserves

Total production by mine—as well as the remaining coal reserves by confidence category—are listed in
Table 2. Proven (measured) reserves are significant when compared to production over the last
42 years.

Table 2: Coal produced from 1970 through 2012 and remaining reserves by category, million tonnes10

Mines

Produced

Measured

Probable

Possible

Total Reserves

Armutguk

20

10

16

8

34

Kozlu

38

70

41

48

159

Uziilmez

58

138

94

74

306

Karadon

62

137

159

117

413

Amasra

12

171

115

121

407

TTK total

190

526

425

368

1,319

4.0 Gas Resources Assessment

Methane emissions from TTK mines are reported as specific emissions, expressed in cubic meters of
methane per tonne (nr/tonne) of coal produced. Figure 9 shows the historical specific emissions by
mine.

9	Ozturk, M. (2013b)

10	Ozturk, M. (2013a)

13

-------
Figure 9: Specific emissions by mine from 197011

30

(O

Kozlu	Karadon	Armutcuk	Amasra	Uzulmez

In-situ gas content has been measured at all of the mines as well. Table 3 compares the average
measured gas content with the specific emissions by mine.

Table 3: Average depth of measured sample, number of samples and comparison of measured gas

content and specific emissions12

Mines

Average
Depth
(m)

Number
Samples

Average gas
content

(m3/tonne)

Average Specific

Emissions
(m3/tonne mined)

Specific
Emissions /
Gas Content

Armutguk

-444

5

4.65

20.95

4.5

Kozlu

-521

29

9.07

20.94

2.3

Uziilmez

-165

11

3.74

9.12

2.4

Karadon

-391

24

7.96

13.84

1.7

Amasra

-186

7

5.49

6.55

1.2

The specific emissions from an active mine will always be greater than the measured gas content of the
mined coals. This is because additional methane is released from coals not mined as well as from other
gas-bearing strata that have been disturbed by the mining process.

The Uzulmez and Amasra mines are the shallowest and have the correspondingly lowest measured and
specific emissions, while the Karadon and Kozlu mines are among the deepest and have correspondingly
higher measured and specific emissions. The Armutguk mine is an exception because, although it is
deep, it has relatively low measured emissions (note the small number of samples), but has high specific
emissions.

11	Ozturk, M. (2013a)

12	Fisne, A. (2013)

14

-------
Table 4 shows the potential for power generation at the five mines assuming they produce coal at their
historical rate, at their average specific emissions rate, and assuming 25% of the total mine emissions
can be captured as gas that is usable in power generation equipment13. Because the Kozlu and Karadon
mines have both high coal production rates as well as high specific emissions, they are the most likely to
be able to drain usable quantities of methane for power generation (See Section 8.0 for utilization
options considered for this study).

Table 4: Historical mining rate and specific emissions used to estimate future mine emissions and
potential power generation assuming 25% emissions capture at usable quality14

Mines

Average Mining
Rate
(Tonne/yr)

Average Specific
Emissions

(m3/tonne)

Methane Emissions
Million
(m3/yr)

Potential Power
Generation
(MWe)

Armutguk

462,647

20.95

9.69

0.969

Kozlu

1,066,389

20.94

22.33

2.233

Uzulmez

1,340,661

9.12

12.23

1.223

Karadon

1,730,070

13.84

23.95

2.395

Amasra

310,654

6.55

2.04

0.204

5.0 Gas Outburst Characterization at TTK

Coal and gas outbursts are a complex, catastrophic, and unstable phenomena that involve the ejection
of large volumes of coal, and are often accompanied by gas, such as methane, carbon dioxide, or a
mixture of the two. Based on previously documented studies discussed below, past coal outbursts are
common at TTK mines and a serious concern for employee safety. Coal and gas outbursts are prevalent
in deep and gassy mines, and where gas drainage is either poor or absent. Shepherd et al (1981)
reported on outburst occurrences in Australia, North America, Europe, and Asia, and found that more
than 90 percent of significant outbursts have been concentrated in the narrow, strongly-deformed
zones along the axes of structures such as asymmetrical anticlines, the hinge zones of recumbent folds,
and the intensely deformed zones of strike-slip, thrust, reverse, and normal faults. These narrow
deformed zones, whether in mesoscopic or mine-scale geological structures, form the loci for stress and
gas concentration. Similar studies in China15 revealed that outbursts nearly always occurred in long,
narrow outburst zones along the intensely deformed zones of strike-slip, reverse, or normal faults,
within which coal has been physically altered into cataclastic, granular, or mylonitic microstructures.

The problem results from a combination of the effects of stress, gas content, and physico-mechanical
properties of the coal. Aside from the stress regime in the mine, a primary explanation for gas outburst

13	A very successful methane drainage system at a typical hard coal mine can drain up to 70% of the total mine
emissions as usable quality gas, with the remaining 30% as low-concentration VAM. However, a more common
result of methane drainage system efficiency is approximately 25% of usable quality gas.

14	Ozturk, M. (2013a)

15	Peng, L.S. (1990)

15

-------
is the increase in the gas pressure gradient as a mine face approaches a permeability barrier such as a
fault zone.

Okten et al (2011) and Fisne & Olgun (2013) have produced assessments of outburst hazards in the
Zonguldak coal basin that helps to explain the location and magnitude of various outburst events. Figure
10 shows the number and frequency of outbursts relative to tonnes of coal mined since 1969 for mines
in the Zonguldak basin.

Figure 10: Outburst frequency and occurrence rate relative to tonnes coal mined16

The number of outbursts peaked in 1974 then declined significantly due to implementation of outburst
control measures such as inseam drilling for gas drainage and gas detection systems. The increase in the
relative rate of outbursts reflects reduced mining rate together with mining at deeper depths.

Okten et al (2011) showed that most outburst occurrences were in the raises and drifts as opposed to
the longwall face and gateways, as shown in Figure 11.

16 Fisne & Olgun (2013)

16

-------
Figure 11: Frequency distribution of locations of outbursts occurred in Kozlu and Karadon Collieries in

Zonguldak Coal Basin17

60

50

53

40

30

£
CD
&_
&_
3
U

u

O

20

34

26

19

-±7-

10

Face

Raise

Location of Outburst

Drift

Gateway
I Kozlu ¦ Karadon ~ Total

Previous outburst studies (Fisne and Olgun, 2013) also found that outburst frequency increased with
mining depth, inclination of the mined seam, seam thickness, and distance to faults. The most striking
correlation is the nearness to faults as shown in Figure 12.

Figure 12: Outburst frequency relative to the distance from a known fault18

10 30 50 70 90 110 130 150 170 190 210 230 250 270 290
Distance from Fault (m)

Fisne & Olgun (2013)
Ibid

17

-------
Fisne & Olgun (2013) also presented Zonguldak outburst data as shown in Table 5.

Table 5: Largest outburst events in the lozlu and Karadon mines19

Date

Coal
Seam

Depth
(m)

Amount of
Ejected Coal
(tons)

Amount of
Emitted Gas
(m3)

Degassing

Factor
(m3/tonne)

Nov., 1969

Sulu

402

120

7,000

58.3

Sep., 1974

Acilik

402

75

9,000

120.0

Dec., 1974

Acilik

401

80

7,000

87.5

Nov., 1975

Acilik

402

45

4,875

108.3

Jun., 1976

Biiyiik

396

60

4,600

76.7

Dec., 1980

Drift

418

80

7,200

90.0

Jul., 1987

Rabut

485

200

5,400

27.0

Feb., 2004

Messoglu

548

620

16,000

25.8

Apr., 1974

Biiyiik

343

20

3,000

150.0

Apr., 1974

Acilik

343

70

8,000

114.3

Mar., 1975

Acilik

356

140

11,000

78.6

Feb., 2006

Messoglu

560

600

16,000

26.7

May, 2010

Drift

540

80

25,000

312.5

May, 2011

Acilik

360

1,500

45,000

30.0

Apr., 2012

Acilik

460

595

17,850

30.0

Jan., 2013

Drift

630

2,040

65,000

31.9

The degassing factor, which is the estimated gas expelled divided by the volume of coal ejected, shows
much more gas was liberated during the event than is either naturally contained within the coal or even
what is emitted as specific emissions (Table 3). This implies gas pressure significantly over the Langmuir
pressure which indicates storage of high pressure gas in the free gas state, possibly in porous fracture
zones or bounding sandstones, or rapid drainage of adsorbed gas from remote locations.

Figure 13 shows the distribution of outbursts by seam based on 64 recorded outbursts.

19 Fisne & Olgun (2013)

18

-------
Figure 13: Outburst frequency by coal seam for both the Kozlu and Karadon mines20

Coal Seams

Table 6 and Table 7 show average measured gas content values for the coal seams by depth in the Kozlu
and Karadon mines, respectively. Gas contents over 10 m3/tonne are considered to be very high.
Considering the average values for the Kozlu mine, three of the seams are very gassy (Seams 25, 38 &
41) and two other seams are also relatively high (Seams 43 & 55).

Table 6: Kozlu high, low, and average measured gas content by seam21

Seam #

Coal Seam

# Samples

High
(m3/tonne)

Low
(m3/tonne)

Average

(m3/tonne)

25

Buyuk

1

NA

NA

11.72

30

Domuzcu

6

7.60

5.30

6.20

38

Rabut

2

12.80

12.82

12.81

41

Milopero

4

19.70

7.75

13.73

43

Hacimemis

5

13.50

5.20

8.00

44

Sulu

3

6.00

5.20

5.60

55

Cay

8

11.40

5.59

9.60

20	Fisne & Olgun (2013)

21	Fisne, A. (2013)

19

-------
Table 7; Karadon high, low, and average measured gas content by seam22

Seam #

Coal Seam

# Samples

High
(m3/tonne)

Low
(m3/tonne)

Average

(m3/tonne)



Akdag

2

5.33

5.30

5.32

25

Buyuk

2

12.10

8.20

10.15

30

Domuzcu

NA

NA

NA

NA

38

Rabut

NA

NA

NA

NA

41

Milopero

3

5.80

4.80

5.47

43

Hacimemis

1

NA

NA

6.64

44

Sulu

12

18.10

6.60

10.06

55

Cay

2

8.70

7.80

8.25

While the measured values show significant gas contents, they are not extreme and they do not
necessarily correlate with the number of outburst events. Some other parameter must be causing the
concentration of outbursts in Acilik, Cay and Sulu; possibly something simple, as these are the most
heavily mined seams.

Other features influencing outbursts (e.g., geologic structures) will still play an important role but in any
case, pre-mining gas drainage of gassy seams appears crucial.

6.0	Outburst Control Leading to CMM Capture and Utilization

Current practices at the Kozlu coal mine to control outbursts have proven inadequate. Currently there is
no gas drainage system (i.e., vented in the mine workings); the design of the outburst control system is
insufficient because the drill cannot reach the end of the heading development; and the drilling
equipment cannot drill far enough ahead to enable outbursts to be located, discharged, and drained
(current limit is 25 meters). (The limited reach of the drilling equipment means that outburst control
techniques and corresponding management processes will continue to be ineffective.)

When assessing CMM drainage practices worldwide, poor outburst management practices and
inadequate safety standards or equipment represent the biggest barrier to safely preventing an
explosive atmosphere from forming. At the Kozlu mine, the central issue is not management practices,
but a lack of financial investment in safety equipment (e.g., inadequate drilling equipment).

6.1	Drilling Equipment

The current drills are not powerful enough to drill the complete face distance for headings (60 to
100 meters). This means the heading is not drained prior to development of the angled roadway, and
outbursts are common.

22 Fisne, A. (2013)

20

-------
6,2 Oiitlim tem Design23

Discussions with TTK revealed that when an outburst is discovered at a drill site, drilling is stopped and a
new, larger bore drill is used to re-drill the hole and increase its diameter. However, the borehole
sealing does not appear to be adequate for sealing against an outburst. Moreover, this approach would
likely cause the drillers to evacuate as soon as signs of a significant outburst were detected. Because the
drill cannot reach the end of the heading development, the design of the outburst system is ineffective.

6.3 Gas Drainage System

When an outburst is detected, there is no means of removing the outburst gas released from the coal.
This means that any gas or coal dust outburst is merely vented within the mine, which is a fundamental
problem.

6.4 Management Processes

Discussions with TTK revealed that drilling personnel do not adhere to the drilling and drainage system
instructions. However, the management processes associated with outburst control might be ineffective
because the drilling equipment is not able to prevent outbursts.

6.5 Methodology ai imatedCost iprovement .tburst'.

To prevent frequent outbursts and resulting injuries or fatalities, the following approach for improving
safety within the mine is recommended:

1. Make improvements to the currently inadequate mine safety equipment.

2. Generate a budget to develop improved outburst control equipment and procedures.

3. Procure new lightweight, powerful in-mine drilling rigs with high-quality rods and bits that have
the capacity to drill 60 to 100 meters.

4. Design and install a new methane drainage pipework system that is capable of extracting
gas/dust away from the drill hole and then outside of the mine.

5. Install a new methane extraction plant (a suitable vacuum pumping station design is available).

6. Design a new outburst control system (incorporating the new drilling system and training for
operators, methane drainage pipework, and methane extraction plant).

7. Develop new outburst management processes that are appropriate to the new equipment and
drainage design.

Budget costs for recommendation #3 above are expected to be approximately $300,000 U.S. dollars
(USD). After demonstrating the drilling equipment performs as recommended, it would then be
appropriate (in a staged sequence) to install underground pipes. The cost of the underground pipes is
entirely dependent on distance to mine shaft and pipe diameter/material, but the estimated cost would
be in the range of $100,000 to $500,000 USD. Once the pipework is installed and the gas is discharged
on the surface, a methane extraction plant could be installed (estimated cost $350,000 USD). The total

23 The project team was unable to visit a drilling site underground due to safety concerns. A subsequent review of
the drainage system was used to evaluate the outburst system design.

-------
budget shown in Table 8, including external drainage design consultants and all equipment, training, and
on the job practical instruction, would be approximately $1 million USD phased in over the course of
two years.

Table 8: Summary of estimated costs for improvement of outburst control

Equipment

Cost ($USD)

Drilling equipment

300,000

Underground piping

100,000-500,000

CH4 extraction plant

350,000

TOTAL (installed)

1,000,000

7.0 Energy Market Information

Turkey has one of the fastest growing economies in the world with annual growth rates of more than 8%
and corresponding demand for energy is expected to double over the next 10 years.24 Figure 14 shows
that Turkey's annual energy consumption exceeds annual production, with a widening gap between
production and consumption since 1980. In 2011, only one-third of Turkey's energy consumption could
be satisfied by domestic energy production and approximately 71% of Turkey's energy use was provided
by foreign fuel sources.

Figure 14: Turkey's total primary energy25

Total Primary Energy

Year

24	EIA (2013)

25	... .

22

-------
Coal-fired power plants are a major energy source in Turkey. In 2011, approximately 30% of electricity
came from the consumption of coal and lignite. Since 1980, coal production has generally increased,
with a decline from 1999 to 2004 and a slight decline in 2009, as shown in Figure 15. According to the
U.S. Energy Information Administration (EIA), there has been renewed interest in the recovery of
Turkey's domestic coal. As of 2008, Turkey's recoverable coal reserves totaled 2.6 billion short tons of
coal, with only about 23% (583 million short tons) of that as hard coal.

Figure 15: Turkey coal production26

1 no



Coal Production

Qfl















oU

(A

C 7H

















£ 70

j. cri





























t OU
O

_C en

















































to

£ do

























































:>n



























































^ o u

i































































ZU

1 n

































































1U

n

































































u

4

i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i

? J? ^

VVVVVVVVV^VV''lr'1ir'V

Year

Natural gas is the largest fuel source consumed in Turkey, primary used in power generation and space
heating.27 In 2012, Turkey produced an estimated 22 billion cubic feet (Bcf) of natural gas and consumed
approximately 1,600 Bcf of natural gas, relying almost entirely on gas imports (Figure 16). Installation of
pre-drainage systems into areas surrounding coal seams would offset some of Turkey's high demands
for foreign natural gas. Depending on the quality of the gas, these pre-drainage systems have the
potential to contribute fuel directly into Turkey's natural gas distribution system.

26	EIA (2013)

27	Peng, L.S. (1990)

23

-------
Figure 16: Turkey's natural gas consumption vs. production28

Natural Gas

Year

The relative contribution of fuel sources for Turkey's power generation is shown in Figure 17, which
shows a significant hydropower sector.

Figure 17: Power generation by sector for Turkey in 201129

Power Generation 2011

Liquids
1.67%

Table 9 shows the commodity prices for years 2011 and 2012 as reported by the European Commission.
Note the gas prices converted from USD/kWh to USD/MMbtu are $11.72 and $8.79 for Household and
Industry, respectively.

EIA (2013)
Ibid

24

-------
Table 9; Turkey half-yearly electricity arid gas prices30



Electricity Prices

Gas Prices



Household

Industry

Household

Industry



(with VAT)

(exclude VAT)

(with VAT)

(exclud

e VAT)



2011

2012

2011

2012

2011

2012

2011

2012

EUR/kWh

0.122

0.131

0.079

0.086

0.029

0.029

0.022

0.022

USD/kWh

0.17

0.20

0.11

0.12

0.04

0.04

0.03

0.03

Carl arket Participation

Turkey has been a major participant in the worldwide voluntary carbon market. In 2011, approximately
5 million voluntary carbon credits valued at $40 million entered the international market mostly from
Turkish hydro projects. The Gold Standard and the Verified Carbon Standard are primarily the two
programs under which Turkish projects are registered. According to the Turkish Carbon Market, Turkish
projects made up approximately 39% of all the 2012 registered Gold Standard projects. The Gold
Standard is preferred with an average 2011 price of about $10.40 over the VCS price of $3.70.31
However, the Turkish Carbon Market estimates future demand for voluntary credits will not increase
and opportunities for carbon projects are nominal without an increase in carbon market prices and
demand.

8.0 End Use Assessment

Although the Kozlu mine is gassy, factors such as low gas permeability, the fractured nature of the coal
geology, and the low, non-mechanized production rates mean CMM pre- or post- drainage techniques
for methane capture prior are likely to be unsuccessful (distinctly separate from outburst control). At
this time, it is recommended that outburst control be the priority. Where a new drilling, drainage, and
extraction system might be implemented, the main target for these holes would be roadway gate
developments; therefore, the drilled holes would be excavated by the developments and there would
be no opportunity for long-term continuous gas extraction.

Currently, gas from coal production is controlled by ventilation only. Note that surface pre-drainage
would be difficult because the incline of the seam is 30 to 60 degrees, and the fractured and non-
homogeneous geology would prevent successful capture. Although it is possible that new gas drainage
systems in mine could tap abandoned mine districts as gas sources, such districts might not be sealed in
a tight manner; therefore, these are unlikely to be available.

Although the mine continues production using manual techniques, CMM drainage would generate gas
only intermittently and at low gas volumes and methane concentrations. This means pipeline injection
would not be technically or commercially viable. Although power generation using gas engines might be

30	European Commission (2013)

31	Peters-Stanley & Hamilton (2012)

25

-------
intermittently technically viable at low gas volumes and concentrations, it would not prove to be
commercially viable. However, gas flaring is considered to be a technical possibility, and this should be
investigated as part of any methane extraction plant design or development.

At the time of the preparation of this study, the recommended technically and commercially viable
option for CMM utilization is VAM to power, using RTOs coupled to waste heat recovery boilers and a
steam turbine. The average methane concentration at the main mine ventilation shaft is >0.6%
methane; therefore, there is sufficient heat energy in the gas to maintain self-sustaining operation of
the RTOs and deliver excess heat via the hot gas bypasses (from each RTO) into a boiler and then to a
superheater connected to an impulse steam turbine. Typical net cycle efficiency would be in the 18 to
28% range, depending on RTO design, boiler design, and steam turbine design.

The steam turbine manufacturing period is within the 9-to 12-month range; therefore, the project
would have a 12-to 14-month implementation period.

It would also be possible to explore the use of RTOs interconnected to an Organic Rankine Cycle
generator or a Rotary Screw generator. (These technologies are lower efficiency at around 15% net cycle
efficiency.)

To develop this project, the high capital investment would demand a long-term power purchase
agreement from the coal mine to buy the electricity—and possibly, revenue from carbon credits.

8.1 VAM Power Economics

The cost of power generation from VAM oxidation heat recovery was estimated for use in pro-forma
economic analysis (before taxes and royalties). These are shown in Table 10 together with the expected
power generation. This is based on sizing for a Kozlu mine ventilation shaft with 0.6% methane
concentration.

e 10: Capital arid operating arid maintenance costs for low and high efficiency power production

from VAM oxidation32

Capital Cost, $

O&M Cost, $/Yr

Power, MWe

Efficiency

High Efficiency

13,360,000

668,000

1.35

28%

Low Efficiency

6,680,000

668,000

0.90

18%

To achieve an economically feasible project, a 15% rate of return for the high efficiency design was
selected in order to offset the significantly higher cost of the initial investment. In order to achieve a
15% return, the following economic analysis shows that using current industrial power sales prices of
0.12 $/kWhr (Table 9) and current carbon prices on the voluntary market of 2.00 $/tC02e will not
provide a positive rate of return. An economic model was run to determine what power price and what

32 Butler, N. (2014)

-------
carbon price might be needed to provide a hurdle rate of return of 15%. This—together with the 10%
NPV and years to capital pay-out—are shown in Table 11 and Table 12*.

Table 11: Economic results for high efficiency VAM power unit
(Power and carbon prices needed to achieve 15% return)



Current Prices

High Power Price

High Carbon Price

Power Price, $/kWhr

0.12

0.24

0.12

Carbon Price, $/tC02e

2.00

2.00

30.00

Rate of Return, %

Not applicable

15%

15%

10% NPV, USD

($6,260,976.56)

$3,551,696

$3,409,808

Pay-out, years

Not applicable

6

6

Table 12; Economic results for low efficiency VAM power unit
(Power and carbon prices needed to achieve 15% return)



Current Prices

High Power Price

High Carbon Price

Power Price, $/kWhr

0.12

0.22

0.12

Carbon Price, $/tC02e

2.00

2.00

21.00

Rate of Return, %

Not applicable

15%

15%

10% NPV, USD

($3,431,509.25)

$1,856,431

$1,753,473

Pay-out, years

Not applicable

6

6

* Both a higher power price and a higher carbon price are required to achieve a 15% rate of return for
the high efficiency design in order to offset the significantly higher cost of the initial investment.

;ervations and Recommendations

The following are some initial observations and recommendations for controlling outbursts, improving
mine safety, and exploring a future CMM utilization project at the Kozlu mine:

•	Generate a budget for improved equipment and procedures for outburst control.

•	Procure new lightweight powerful in-mine drilling rigs with high quality rods and bits that have
the capacity to drill 60 to 100 meters and train personnel on usage of the equipment.

•	Design and install a new methane drainage pipework system in the mine capable of extracting
gas/dust away from the drill hole and then away to the outside of the mine.

•	Install a new methane extraction plant (a suitable vacuum pumping station design is available).

•	Develop a new outburst control design and implementation protocol (incorporating the new
drilling system and training for operators, methane drainage pipework, and methane extraction
plant).

•	Develop new outburst management processes that correspond to the new equipment and
drainage design and procedures.

27

-------
• Once these outburst control recommendations are established, drainage volumes and gas
quality should be monitored to determine the feasibility of establishing a technically and
economically feasible end use technology for the mine methane.

10.0 Conclusions

The objective of this pre-feasibility study, commissioned by USEPA, is to develop recommendations to
reduce methane gas outbursts in the Kozlu coal mine and evaluate the potential to capture methane for
utilization. Based on a meeting with TTK and a preliminary analysis of the information gathered during a
site visit, the Kozlu coal mine was selected for this pre-feasibility study due to opportunities for
improving safety (i.e., reducing outbursts) and CMM recovery and utilization.

Turkey's hard coal resource is restricted to a relatively small area along its northwest coast of the Black
Sea. The coal measures are composed of numerous seams with high gas content. Mining conditions are
extremely difficult because of intense faulting and folding of the strata with inclinations of up to 90
degrees. Difficult mining conditions, together with high gas contents and low permeability, have led to
numerous coal outbursts, many of which have been catastrophic. Because of the complex nature of the
geology, mechanized mining methods cannot be used so the mining is very labor intensive, exposing
many miners to the hazards posed by the outburst conditions.

Coal outbursts occur in all major coal basins of the world and are generally controlled with pre-mine
drainage. At the Kozlu mine, current practices to control outbursts have proven inadequate. Currently
there is no gas drainage system (i.e., vented in the mine workings); the design of the outburst control
system is insufficient because the drill cannot reach the end of the heading development; and the
drilling equipment cannot drill far enough ahead to enable outbursts to be located, discharged, and
drained. (The limited reach of the drilling equipment means that outburst control techniques and
corresponding management processes will continue to be ineffective.)

To prevent frequent outbursts and resulting injuries or fatalities, the Kozlu mine should make
improvements to the currently inadequate mine safety equipment; generate a budget to develop
improved outburst control equipment and procedures; procure new in-mine drilling rigs that have the
capacity to drill 60 to 100 meters; design and install a new methane drainage pipework system that is
capable of extracting gas/dust away from the drill hole and then outside of the mine; install a new
methane extraction plant; and design a new outburst control system and management processes (e.g.,
worker training).

With an investment of approximately $1 million USD, adequate equipment and training can be obtained
that will dramatically reduce the probability of catastrophic coal outbursts at Kozlu. While outburst
control should be a first priority moving forward at the Kozlu mine, establishing an in-mine drainage
system to take the drained gas to a surface pumping station where it can be flared would also reduce
the mine's GHG emissions. The ventilation air at the Kozlu mine was found to be greater than 0.6%
methane, which could be sufficient for VAM oxidation together with steam power generation. However,
using current power sales and carbon sales price does not generate sufficient economic return. A

28

-------
significant premium in either power sales price and/or carbon credit price would be required to provide
a hurdle rate of return of 15%. Finally, after the outburst control recommendations are fully
implemented and under control, drainage volumes and gas quality should be monitored to determine
the feasibility of establishing a technically and economically feasible recovery and use project for the
mine methane.

) References

Butler, N. (2014): Personal communication between Neil Butler, Harworth East Limited, and Ronald
Collings, Ruby Canyon Engineering.

EIA (2013): U.S. Energy Information Administration: Turkey: Country Analysis Brief Overview.
www.eia.gov/countries/countrv-data.cfm?fips=TU.

European Commission (2013): "Energy Price Statistics."

epp.eurostat.ec.europa.eu/statistics explained/index.php/Energy price statistics.

Fisne, A. (2013): Personal communication between Dr. Abdullah Fisne, Istanbul Technical University, and
Ronald Collings, Ruby Canyon Engineering.

Fisne, A. and E. Olgun (2013): "Coal and Gas Outburst Hazard in Zonguldak Coal Basin of Turkey, and
Association with Geologic Parameters" (pre-publication), Istanbul Technical University, Mining
Engineering Department.

Hosgormez, H. (2007): Origin and secondary alteration of coalbed and adjacent rock gases in the
Zonguldak Basin, western Black Sea Turkey. Geochem J 41:201-211.

Okten, G., A. Fisne, T. Hucaverol, C. Onur and E. Gunay (2011): "Assessment of Coal and Gas Outburst
Hazards in Zonguldak Coal Basin, Turkey,"22nd World Mining Congress & Expo, September 2011,

Istanbul, Turkey. NOTE: Presentation is not available online.

Ozturk, M. (2013a): Personal communication between Mesut Ozturk, Turkish Hardcoal Enterprises (TTK),
and Ronald Collings, Ruby Canyon Engineering.

Ozturk, M. (2013b): Introductory Notes on Turkish Hardcoal Enterprise (TTK), Mesut Ozturk, TTK.

Peng, L.S. (1990): Introduction to gas-geology. Beijing: China Coal Industry Publishing House. NOTE:
Publication is not available online.

Peters-Stanley, M. and K. Hamilton (2012): "Developing Dimension: State of the Voluntary Carbon
Markets 2012." Ecosystem Marketplace and Bloomberg New Energy Finance, www.forest-
trends.org/documents/files/doc 3164.pdf.

-------
Shepherd, J., L.K. Rixon, and L. Griffiths (1981): "Outbursts and geological structures in coal mines: a
review." Int J Rock Mech Min Sci Geomech Abstr 1981; 18(4):267-83. NOTE: Journal access can be
obtained at www.sciencedirect.com/science/article/pii/014890628191192X.

Toprak, S. (2009): Petrographic properties of major coal seams in Turkey and their formation. Int J Coal
Geol 78:263-275. NOTE: Journal access can be obtained at
www.sciencedirect.com/science/article/pii/S016651620900Q433.

Virginia Polytechnic Institute and State University (Virginia Tech) Virginia Center for Coal & Energy
Research (2012): "Optimizing Degasification Systems to Reduce Methane Emissions from Turkish Coal
Mines/' Blacksburg, VA.

30

-------