FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF

NORTHEAST INDIA

Dr Diganta Sarma Independent Consultant

(Afro-Asian Region) Mining-Geotechnical & Infrastructure

Development Consultant dr.d.sarma@gmail.com

Dr (Mrs.) Subrata Borgohain Gogoi Associate Professor

Department of Petroleum Technology, Dibrugarh University, Assam, India,

subrata@dibru.ac.in

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

Botswana has no known petroleum reserve, imports petroleum products from South Africa. India has inadequate petroleum reserve, imports mostly from Middle-East

Botswana spent $9.25 billion in the year 2011-12 (DEA Source), an amount more than the country's total annual earnings from exports for the same period (CIA Source)

In the year 2011-12 India imported crude oil of value $160 billion, an amount equivalent to more than half of the country's total annual earnings from exports for the same period

Analysis of Botswana's demand on petroleum products indicates that there is exponential growth of petroleum consumption since 2012

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

Reasons attributable to the exponential growth of petroleum consumption is due to the increase in transportation activities as well as increase in traffic congestion.

While former supports, the latter influences negatively onto the economic activities.

Impact of congestion can be mitigated through sustainable and energy-efficient-transportation-system - a model both Botswana and India need to consider.

In order to reduce import of petroleum crude and refined fuels for India and Botswana respectively and thereby use such funds for other development works, the immense coal reserve has been identified as an alternative resource for energy.

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

Use of Botswana Coal resource is presently focused for two purposes :

- generation of electric power and

- export of raw coal

Unless there is an efficient and smart power-gird-system amongst SADC or regional member countries, Botswana to become a regional power hub may not be possible in the near future as distribution loss will be significant vitiating advantage of strategic location.

Signature of power-distribution-treaty amongst member countries need considerable regional-political-leadership and motivation, which may be a potential barrier similar to the interference of Zimbabwe for implementing the Kazungula corridor.

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

In context to exporting raw-coal to the Western World including Europe through Walvis Bay corridor and to Asia (India and China) through Mozambique and/or South African corridors, there are a number of issues need to be considered for comprehensive feasibility study .

Mozambique and South Africa being coal producing nations, transportation of Botswana coal though those corridors needs careful and pragmatic evaluation in context to the landed-cost per MT of Coal at the respective sea ports.

On the other hand although apparently Namibia's coal expropriation and transportation cost is higher than the landed cost of Botswana's coal at Walvis Bay, design and construction of an efficient railway system may be a serious challenge.

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

Besides ensuring energy-efficient-railway system in general, there are two specific techno-environmental problems in Walvis Bay rail corridor:

- the challenge of designing a wildlife-friendly-system for a railway line that would pass across more than 800 Km of Kalahari and Namib wildlife area

- the impact of active desert on the railway

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

In order to mitigate rail-animal conflict, consequence of which may be severe, identification and construction of

safe-passages of wildlife is an important requirement although such construction in plain terrain is very costly.

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

Impact of active-desert on railway track is common in Walvis Bay area as that has some of the highest and active sand dunes.

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF NORTHEAST INDIA

The previous discussion indicates that there is considerable risk for the investment in bulk-transportation of coal unless an energy-efficient-transportation-system is found feasible.

Such risk may not exist for local environmental-friendly-use of coal with an objective of exporting finished product. Such products may be power generation and Coal TO Liquid (CTL) fuel.

In this presentation an outline of feasibility of Botswana coal liquefaction based on the experience of Northeast India has been explored as Botswana has huge reserve of coal.

Today’s demand for the Conventional liquid-fuels from crude oil can be substituted by the alternative liquid-fuels from coal

Liquefaction of coal can be achieve through the Coal-To-Liquid (CTL) technology

There are two types of CTL technologies:

- Direct Coal to Liquid (DCL)

- Indirect Coal to Liquid (ICL)

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF

NORTHEAST INDIA

CTL has its roots in Germany. DCL was developed by Fredrich Bergius in 1917. Bergius was awarded Nobel Prize in 1931 for his work on CTL

Subsequently CTL–ICL was developed by Franz Fischer and Hans Tropsch (FT Process) in 1923

There are considerable developments since 1923 and currently many countries are undertaking further development on CTL technologies.

FEASIBILITY STUDY OF BOTSWANA COAL LIQUEFACTION BASED ON THE EXPERIENCE OF

NORTHEAST INDIA

The biggest CTL–ICL (FT) on the low cost coal is by South Africa Synthetic Ltd. at its Sasol Plant with production capacity of about 160,000 b/d.

CTL World wide

Resources Reserves Production

India

Coal 55.6 Bt 588.5 Mt

Crude oil 775 Mt 45 Mt

Botswana

Reserves Production

Coal 7.1 Bt 3 Mt

Crude oil 0 0

Map of NE India coal field (Study Area)

Map of Botswana showing

the producing coal field

COAL A

RESOURCE

Coal in Botswana

Botswana has extensive, large unexploited coal resources (212 Bt of which 7.1 Bt are measured reserves)

Morupule Colliery Ltd is Botswana’s only operating coal mine, since 1973, produces about 3.0 Mt per annum

The Morupule contains coal of medium to low grade sub-bituminous type suitable for CTL technology

Sl.

no.

Coalfield Deposit Company Total

Tonnes

Measured

(Mt)

Indicated

(Mt)

Inferred

(Mt)

1 Dukwe Dukwe Asanjo 922 - 508 414

2 Foley Sese African Energy 2,800 500 2,200 109

3 Foley Sese NW Daheng 850 - 850 -

4 Serule Sechaba Shumba 968 - - 968

5 Serule Lechana Asenjo 830 - 103 727

6 Serule Tshimoyapula Asenjo 1,174 - - 1,174

7 Morupule Morupule Debswana 2,900 425 - 2,483

8 Morupule Morupule South Hodges 2,330 - - 414 9 Moiyabana Moiyabana Hodges 15,000 - - 15,000

10 Mmamabula Mmamabula CIC Energy 2,346 2,313 2 31

11 Mmamabula Mmamabula West Asenjo 5,364 - 573 4,791

12 Mmamabula Mmamabula South Under tender 617 553 57 7

13 Mmamabula Mmamabula Central Under tender 408 - - 408

14 Letlhakane Mmamantswe Aviva Corp 1,300 895 405 -

15 Dutlwe Takatokwane Nimrodel 4,230 - - 4,230

TOTAL 28,539 4,686

2012 Total Tonnes (IN-SITU) after Geological Losses, Top 200 to 300m

Area Dep. (m)

Measured (Mt)

Ind.

(Mt)

Inf.

(Mt)

Total

(Mt)

Assam 0-600 314.59 26.83 34.01 375.43

Arunachal

(Namchik) 0-300 31.23 40.11 18.89 90.23

Meghalaya 0-300 117.83 40.89 300.71 459.43

Nagaland 0-300 3.43 1.35 5.22 10.00

Total 0-600 467.08 109.18 358.83 935.09

CoCoalReservealCCcReservesof N

467 Mt NE coal has the capacity of generating 200 Mt of liquid fuel

NE COAL RESERVES

Comparison between Bituminous Coal, NE Coal & Botswana coal

0

10

20

30

40

50

1 2 3

Std. Bituminous coalfor DCL

NE coal

Botswana coal

Ash % VM % S % others %

Bituminous coal 10 42.5 0.5 47

NE coal 10.26 43.32 3.48 42.94

Botswana Coal 23.74 22.55 22.5 31.21

CTL PROCESS: TECHNOLOGY OPTIONS

Direct Liquefaction

(DCL)

Indirect Liquefaction

(ICL)

NE coal samples were obtained from Tirap Open Cast project

from Makum Coalfield (27°15′–27°25′N; 95°40′–95°55′E) area

lies along the outermost wing of the Patkoi range in Tinsukia

district of Assam located at 10–15°N palaeolatitude

The samples were

Collected from 18.29m

(60ft) seam which

have thickness of 16m

DCL Technology of NE Coal

MATERIALS

Components Amount (wt %)

Ash 5-10

Volatile Matter (VM) 40-45

Moisture 2-3

Total Sulphur 1.5-6

Fixed Carbon (FC) 47 (approx.)

Coal Feed Analysis for DCL

25

CTL Program Milestones of Oil India Limited

1998 to

2002

Results Activity Technology

Phase I completed

Pilot Plant Run & Feasibility Study

HTI’s Direct Coal liquefaction (DCL) - Coal-

only process

-- do -- Test Runs & Feasibility

Performed

Axens NA’s Catalytic Two-Stage Liquefaction (CTSL) -

Coal-only process

Good Conversion,

Premium Product

Pilot Plant Commissioned

Test Runs &

Feasibility Performed

Axens NA’s Coal-oil

Co-processing -

Coal + VTB (Vacuum Tower Bottom)

2002 to

2004

2004 to

2006

H:C ratio in coal : 0.3 - 0.8

H:C ratio in Oil : 1.6 to 2.0

H2 + O H2O

H2 +S H2 S

1.5H2 + N NH3

Mechanism of DCL

Break down of large coal smaller molecules Addition of H2

Removal of O2 , S & N2 impurities

CTL PROCESSes

DCL ICL Advant-

ages A conceptually simple process

Produces high octane gasoline

Is more energy efficient than ICL

Products have higher energy density

than those from ICL

Ultra-clean products

Well suited for CO2 capture

Well suited for electric power

coproduction

May have longer operating

expenses than DCL

Disad-

vantages The product can have high aromatic

content

The diesel produced has low cetane

number

The process may have higher

operating cost than ICL

Conceptually more complex than

DCL

Less efficient fuel production than

DCL

Produces low octane gasoline

Petrol products have lower energy

density than those from DCL

DCL and ICL

DCL ICL Spec/Typical

Diesel

Conventional

Diesel

Specific gravity 0.865 0.780 0.82-0.85

Cetane 42-47 70-75 >40

Sulfur (ppm) <5 <1 <15

Aromatics (%) 4.8 <4 <35

Higher heating value (Btu/gal) 138, 100 129, 800 138, 700

Naphtha Conventional

Gasoline

Specific gravity 0.764 0.673 0.72-0.78

Octane (RON) >100 45-75 85-95

Sulfur (ppm) <0.5 Nil <30

Aromatics (%) 5 2 <27

Higher heating value (Btu/gal) 133, 000 116, 690 124, 800

Comparison of CTL end product characteristics

PROSPECTS OF COMMERCIALIZATION OF THE PROJECT IN ASSAM

• Efforts made by Ministry of Coal/Coal India Limited (CIL)

• Performance and Cost

• Potentials and Barriers

Efforts made by Ministry of Coal/CIL

• A global tender was floated in 2001 by Central Mine Planning &

Design Institute (CMPDI) of Govt. of India for setting up a CTL

plant in India based on high ash Indian coals (>10.26 wt%) for a

nominal capacity of 1 Mt of liquid and gaseous products / year

• On the request of OIL a study was taken up by CIL for assessing

the availability of NE coal to meet the likely requirement of coal

for commercial DCL to be set up by OIL

• CIL assessed coal availability of 3.50 Mt against OIL's

requirement of 4 to 5 Mt

CTL meeting the Environmental Challenges

• A major concern of CTL plants is their emissions of CO2

• If coal liquefaction was done without employing

either Carbon Capture and Storage (CCS) technologies

or biomass blending, this resulted in lifecycle GHG

footprints

• For future CTL projects, CO2 sequestration is proposed

to avoid releasing CO2 into the atmosphere

Conclusion

The benefits of CTL can be realised in countries that rely heavily on oil imports & have large domestic reserves of coal

Botswana will need to consider the significant volumes of water required for a CTL plant

Botswana have to deal with techno-economic and environmental issues associated with CTL

Botswana have to develop necessary

infrastructure

In view of rising crude oil prices, CTL plants will remain a viable proposition & will also go a long way for supplying alternate fuel source

However, government policies must be more cognizant of the broader and longer term impacts of CTL on county’s energy security

The overwhelming response received from Industries for setting up CTL projects particularly in India is truly encouraging

CTL technology can bring cleaner transport fuel, reduce GHG through CCS and EOR and contribute greatly to the energy basket of our country.

Courage to Explore, Knowledge to Exceed, Technology to Excel

Courage to Explore, Knowledge to Exceed, Technology to Excel

Questions related to petroleum technology shall be addressed to Dr (Mrs.) Subrata Borgohain Gogoi, Associate Professor, Department of Petroleum Technology, Dibrugarh University, Assam, India, Email : subrata@dibru.ac.in

Questions related to geotechnical and transportation engineering shall be addressed to Dr D. Sarma, Cell: +267-71483232, Email: dr.d.sarma@gmail.com