CO2 mineral sequestration studies in the ultramafic rocks of northern Pakistan.
One of the greatest threats to environment caused by anthropogenically induced climate change is the production of CO2 as a result of industrialization. How to get rid of, or at least reduce it in the atmosphere to save the environment, is one of the biggest challenges of the day. Under controlled experimental conditions with optimized reaction kinetics, mineral carbonation has considerable potential for the safe disposal of CO2 in the form of environmentally benign carbonates. Pakistan has many major ultramafic complexes with varying thickness and lithologies containing Ca and/or Mg rich silicate minerals, such as pyroxene, olivine, amphibole, serpentine, etc. Our present work is about the mineral carbonation potential of ultramafic rocks of Pakistan, including Chilas and Jijal complexes, Alpuri serpentinites and Dargai ultramafics. The calc-silicates exist in abundance in all of these ultramafic bodies and may act as possible sinks to sequester CO2 in the form of magnesium and calcium carbonates.
In this study, approximate amounts of CO2 that can be sequestered in all the ultramafic rocks of Chilas, Jijal, Alpuri and Dargai are estimated using equation formulated by Zevenhoven and Kohlmann, (2001). The approximate covered area of the Chilas complex is 7318 km2, Jijal complex 551 km2, Alpuri serpentinite 16 km2 and that of Dargai ultramafic belt is 153 km2. Taking into consideration the depths, densities and MgO contents, the estimate shows that an ultramafic proportion of 1 million ton (mt.) in the Chilas, Jijal, Dargai, and Alpuri ultramafic can store ~ 01268, 93.79, 47.82 and 1.79 mt of CO2, respectively.
Keywords: CO2 Sequestration; Chilas; Jijal; Dargai; Alpuri; Ultramafics
The carbon dioxide (CO2) level has been increasing in the atmosphere by different human activities, including burning of fossil fuels and other anthropogenic activities. The atmospheric CO2 concentration has been increased (US Department of Commerce report, 2006). Disturbance in the global carbon cycle over the past century has influenced the global climate very badly; leading to warmer temperatures, increased ice melts, especially in the polar regions and rise in sea level (Energy Information and Administration USA report, 2010). It is now evident that the rise in CO2 concentration within the atmosphere is one of the main causes for the apparent rise in the average global temperature. In order to address this problem, a research was conducted under the sponsorship of US Department of energy in order to find an industrially and environmentally worthwhile and improved carbonation method to allow minerals sequestration to be implemented economically (Philip et al., 2000).
The team made meaningful success in looking for faster reaction techniques by using magnesium silicates, supercritical CO2, water, and additives for pretreatment methods to increase mineral reactivity, and in analyzing the structural changes to identify reaction paths and probable barriers. This geochemical trapping system for storing the CO2 underground is based on the weathering/alternation processes occurring in nature, wherein CO2 reacts with Ca, Mg and/or Fe-bearing silicate-rich rocks such as ultramafics and mafics to form the respective carbonates.
Pakistan, being a developing country is suffering from rise in fossil-fuel CO2 emission levels. For example, Sheikh (2010) reported in his work that in the fiscal year 2002-2003, the consumption of coal in cement industry and brick kilns in Pakistan was 19.6% and 53.3%, respectively and the percentages in the fiscal year 2007-08 was changed to 56.6% and 37.2%, respectively.
Pakistan needs to address this problem on urgent basis in order to save its agriculture on
which relies its 70 % population. Partial solution to this problem can be obtained by disposing the excess CO2 by capturing it from the point sources, separating it from flue gases and storing into potential reservoirs other than the atmosphere, which is referred to as carbon sequestration. The potential reservoirs include terrestrial biosphere, oceans and geological formations for storing the CO2 underground. There are many geological formations, like deep saline aquifers, depleted oil and gas fields, unmineable coal seams, oil-bearing shales, mafic/ultramafic rocks and especially the continental flood basalts that offer better and promising receptors for the long-term sequestration of CO2 compared to other reservoirs. This study deals with the geological formations within Pakistan that can act as reservoirs for carbon sequestration (Fig. 1).
2. Carbon dioxide storage in geological formations
There are three different ways for carbon dioxide sequestration in geologic formations, i.e. hydrodynamic trapping, solubility, and mineral trapping. (Mani et al., 2008).
2.1. Hydrodynamic trapping
It involves the storage of free CO2 as gas or as supercritical CO2 in the pore spaces of the sedimentary layers overlying oil and gas reservoirs, un-mineable coal seams, and deep saline reservoirs. These structures serve as a natural storage of for hydrocarbons, brine, and CO2. In the developed countries, power plants and other large emitters of CO2 are commonly installed near these geological strata with potential for CO2 storage (USDE, 2010). In many cases, the recovery of hydrocarbons is increased by penetrating CO2 into the geologic formation, thus providing value-added byproducts that make the capture and sequestration, of CO2 cost effective too (USDE, 2010). This technique ensures that sequestration does not impair the geologic integrity of an underground formation and that CO2 storage is secure and environmentally acceptable.
In this type of trapping, CO2 is dissolved in fluid phase comprising of aqueous brines and oils. The solution has density greater than brine in order to prevent buoyant escape of CO2 (Weir et al., 1995). The solubility of CO2 varies as a function of pressure, temperature, total salinity and brine composition.
2.3. Mineral carbonation trapping
It is a permanent mechanism of sequestration in which silicate minerals are converted to secondary carbonates due to reaction with CO2 (Mani et al., 2008). Detailed background of this technique is given below.
3. Mineral CO2 sequestration: Brief review
The basic principal of mineral CO2 sequestration is the acceleration of weathering/alteration processes occurring in nature, wherein CO2 reacts with Ca, Fe and or Mg containing minerals, especially silicates. For industrial applications, the process is largely to be completed in hours compared to the natural weathering reactions, which take considerable time. Thus optimization of reaction kinetics is of prime importance in mineral. The permanent sequestration of CO2 in the form of carbonates is shown by this reaction.
(Ca, Mg)O + CO2 - (Ca, Mg)CO3
(Ca, Mg)SiO4 + CO2 - (Ca, Mg)CO3 + SiO2.
Nature stores CO2 predominantly in carbonates, mainly limestone, dolomite. Listwanite (carbonated serpentinite) represents a fossil mineral carbonation system, serving as a repository of CO2 in the form of carbonates during the reaction of serpentine with CO2-rich fluids (Kump et al., 2000; Kojima et al., 1997). CO2 is made to react with mafic/ultramafic rocks which are the most common source of magnesium, iron or calcium-bearing silicate minerals present in nature (Goff and Lackner, 1998). Examples of such a carbonation reaction with suitable magnesium minerals (Mani et al., 2008) are:
Mg3SiO5(OH)4 + 3CO2 - 3MgCO3 + SiO2 + H2O (Serpentine)
(Magnesite) (Silica) MgSiO4 + 2CO2 - 2MgCO3 + SiO2
(Olivine) (Magnesite) (Silica)
The reaction of industrial waste acids with olivine on enhanced rates (i.e., industrial time scale) was investigated by Schuiling et al. (1986), Jonckbloedt (1997) and Lieftink (1997). In a subsequent study, Schuiling and Krijgsman (2006) demonstrated that olivine reacts with compressed CO2 in autoclaves, in the presence of right catalysts, in a matter of hours, which testifies to feasibility of industrial application of CO2 sequestration. The main advantage of mineral carbonation is the thermodynamic stability of the formed carbonates, which makes the storage permanent and inherently safe (Lackner, et al., 1997). Furthermore, carbonation reactions are exothermic, which enables reduction of energy consumption and costs (Goff and Lackner, 1998; Lackner et al., 1997).
CaO + CO2 - CaCO3 (D Hr = 179 kJ/mol) MgO + CO2 - MgCO3 (D Hr = 118 kJ/mol) Where Hr is the heat released in the reaction.
Finally, the potential of the technology to store appreciable amounts of the CO2 resulting from fossil fuel combustion is large enough because serpentine, olivine, and pyroxene-rich rocks occur in large amounts in nature (Goff and Lackner, 1998; Lackner, et al., 1997). Olivine is slow to react and serpentines react poorly, unless pretreated to remove chemically bound water. At a high temperature of ~600degC and pressure of about less than 0.5 kbar, the reaction has favourable conditions for kickstarting the carbonation pathways (Pokrovsky and Schott, 1999).
4. Potential of usage of ultramafic rocks for CO2 for carbon sequestration in Pakistan
The primary requisite for using mineral carbonation technique for CO2sequestration is availability of suitable ultramafic rocks containing Mg, Ca and Fe silicate minerals e.g., olivine. Olivine is a common constituent of dunites and peridotites. These rocks are typically abundant in mantle, exposed on Earth's surface as ophiolites. In crustal settings, they form as a part of layered complexes formed in deep-seated basaltic magma chambers as cumulates and are exposed to surface through tectonic exhumation processes. Northern Pakistan is famous for its tectonic evolution as a continent-island arc- continent collision zone involving closure of
Neotethys and collision between the Indian and Eurasian plates with entrapment of the Kohistan fossil-island arc in a broad suture zone between the two colliding plate (Tahirkheli et al., 1979). Ultramafic rocks in northern Pakistan occur both as part of the Kohistan island arc (Jan and Howie, 1981), as well as obduction of ophiolites onto the subducting Indian Plate (DiPietro et al., 2000). In the following we briefly review the occurrence of ultramafic rocks in northern Pakistan for their possible usage in CO2 sequestration.
4.1. The Chilas complex
Chilas complex is a massive intrusive body occupying the midrib of the Kohistan island arc (Khan et al., 1989). Chilas complex makes a substantial contribution towards forming the mass of the plutonic crust of the island arc, the Kamila amphibolites and Kohistan batholith being the other major contributors. It stretches for over 200 km from western Dir to Nanga Parbat and attains a width of over 40 km in the centre. Much of the complex comprises gabbronorites with lensoide bodies of ultramafic rocks scattered throughout the complex but being most abundant in the vicinity of Chilas covering with a cumulative exposure of ~5 km2.
4.2. The Dargai (Skhakot-Qila) ophiolite complex
This ophiolites constitutes an arc-shaped body of ultramafic rocks emplaced in the northern end of the Peshwar basin on the southern side of the Malakand range. It was emplaced over metamorphosed pelitic, calcareous and carbonaceous rocks ranging from Precambrian (Manglaur formation) to Triassic (Saidu formation) (Ahmad et al., 1998). Different geophysical studies like gravity and magnetic delineate that it is about less than 1.5 km deep klippe comprising of ultramafic rocks that overlies the Indian plate about 30 km south of the Indus suture zone. It forms part of the vast Indus suture melange zone (Hussain et al.,1984) and it may be regarded as the western extension of the Indus suture melange zone and grouped with other melanges of the Indus suture (DiPietro et al., 2000). The ultramafic rocks consist predominantly of harzburgite, followed by wehrlite and dunite.
4.3. The Jijal complex
Jijal complex constitutes the southernmost part of the Kohistan island arc (Jan and Howie, 1981; Coward et al., 1986; Jan and Windley, 1990; Kausar et al., 1998). It occurs in the hanging wall of the Indus suture and covers an area of about 150 km2. It forms structurally the lowest part of the arc along which it was thrust onto the Indian plate, The complex is marked by a series of (generally layered) granulite facies metamorphosed mafic and ultramafic rocks including dunites, peridotites, wherlites and websterites (Jan and Howie, 1981; Jan and Windley, 1990).
4.4. Alpuri ultramafics
The ultramafic rocks form part of the Indus suture melange south of the MMT in the Alpurai area of Swat area. There are a number of ultramafic bodies emplaced along the thrust, the largest being the 7x1 km lensoid serpentized mass west of Alpuri. A small lens of serpentinised mass occurs within the schists outcropping along the road just to the south of the main mass and MMT. The trend of the main body is almost north-south. The rocks are brownish to green to grey, hard, massive and medium to fine-grained. Serpentinization is wide-spread. Intense shearing is seen at the contact with other rock units. On the northern end of the body asbestiform serpentine is also noted which imparts a fibrous appearance to the rock (Khan and Humayoun, 1980).
5. Quantification of ultramafic rocks for CO2 sequestration
In order to quantify various ultramafic rocks of Pakistan for their carbon storage capacity, the weight percentage of MgO (Goff and Lackner,1998; Zevenhoven and Kohlmann, 2001) has been taken into account. Detailed information about the geology and structure of ultramafics and data on their areal distribution, approximate thickness, chemical composition and mineralogy are utilized to calculate the volume of ultramafic rocks in Chilas, Dargai, Jijal and Alpurai areas. The volume thus calculated was then multiplied by wt% of MgO to assess the quantity of ultramafic rocks needed to sequester CO2 in these using the following formula of Zevenhoven and Kohlmann, (2001):
Where T is the amount of CO2 that can be sequestered, r is the % MgO in ultramafics, a is the area, t is the thickness, d is the average density and o the average porosity of ultramafics.
a. For the Chilas mafic-ultramafic complex, an effective sequestration of about 20% at a depth of 1 km is calculated as: Volume of the complex=7318x1=7318 km3 Effective volume of the complex for sequestration = 20% of 7318 = 1463 km3 = 1463 x 106 m3.
Average density = 3197 kg/m3.
Mass of ultramafics = volume x density =1463x106m3x3197 kg/m3= 4677x109 m3.
Average % MgO in ultramafics = 27.67%
Total MgO in ultramafics of Chilas Complex = 27.67% of 4677x109m3= 1294 million tons (mt.).
Since 1 ton of MgO can dispose of approximately 1on t of CO2 (Zevenhoven and Kohlmann, 2001), with an average porosity of 2% in ultramafic rocks, 1294 mt of MgO in Chilas Complex can sequester 1x1294x(1-0.02) = 1268.12 mt. of CO2 in the form of magnesium carbonate.
b. For the Jijal Complex, an effective sequestration of about 20% of the complex at a depth of 1 km is calculated as:
Volume of the complex=551x1=551 km3
Effective volume of complex for sequestration = 20% of 551 = 110 km3 = 110x106 m3
Average density = 3000 kg/m3
Mass of ultramafics = volume x density = 110x106 m3 x 3000 kg/m3= 330 million tons (mt)
% MgO in ultramafics = 29% (average) (Jan and Howie, 1981)
Total MgO in ultramafics of Jijal = 29% of 330 mt = 95.7 million tons (mt)
Since 1 t of MgO can dispose of approximately 1 t of CO2 (Zevenhoven and Kohlmann, 2001), with an average porosity of 2% in ultramafic rocks, 95.798 mt of MgO in Jijal Complex can sequester 1x95.7x(1-0.02) = 93.79 mt of CO2 in the form of magnesium carbonate.
c. For the Dargai Ultramafics, considering an effective sequestration of about 20% at a depth of 1 km:
Volume of the Dargai Ultramafics= 153
x1 = 153 km3
Effective volume of belt for sequestration = 20% of 153 = 30 km3= 30 x 106 m3. Average density = 4071 kg/m3.
Mass of ultramafic bodies = volume x density = 30 x 106 m3 x 4071 kg/m3= 122 million tons (mt).
% MgO in ultramafics = 40% (Ahmed,1988)
Total MgO in ultramafics of Dargai = 40% of 122 mt = 48.8 million tons (mt). Since 1 t of MgO can dispose of approximately 1 t of CO2 (Zevenhoven and Kohlmann, 2001), with an average porosity of 2% in ultramafic rocks, 48.8 mt of MgO in Dargai Ultramafics can sequester 1x48.8x(1-0.02) = 47.82 mt. of CO2 in the form of magnesium.
d. For the Alpuri Serpentinites, considering an effective sequestration of about 20% to a depth of 1 km:
Volume of the serpentinites=16x1=16 km3
Effective volume of serpentinites for sequestration = 20% of 16 = 3.2 km3=3.2 x 106 m3.
Average density = 3300 kg/m3.
Mass of serpentinites = volume x density = 3.2 x 106 m3 x 3300 kg/m3= 10. 56 million tons (mt).
% MgO in serpentinites = 17.37%
Total MgO in Dargai Serpentinites = 17.37% of 10.56mt= 1.834272 million tons. Since 1 t of MgO can dispose of approximately 1 t of CO2 (Zevenhoven and Kohlmann, 2001), with an average porosity of 2% in ultramafic rocks, 1.834272 mt of MgO in Dargai Serpentinites can sequester 1x1.834272 x(1-0.02) = 1.79 mt of CO2 in the form of magnesium carbonate.
All the results obtained are presented in Table
1. The estimates, however, can be further improved by including the reaction kinetics and hydrological parameters in the equation.
Table 1: Various properties of samples from different areas and their sequestration potential
###Mass (Million###MgO###CO2 Sequestration Potential
This assessment provides the probable amounts of CO2 that can be stored as mineral carbonates in ultramafic rocks of Chilas, Dargai, Jijal and Alpuri areas. If the effective sequestration amounts to be 20% of the total, from this computation it is observed that approximately 1268, 94, 48, and 2million metric tons of CO2 can be sequestered in the ultramafics rocks of Chilas, Jijal, Dargai, and Alpuri ultramafics respectively. For the year 1999, the carbon emission rate of Pakistan was 92 million metric tons, out of which 26 million metric tons had been contributed by the manufacturing units and construction industry (www.asianewsnet.net/climate/pdf/pakistan_profi le). The estimates shown here exemplify the sequestration potential capacity of the ultramafic rocks. The low porosity, structural features and chemical compositions of the mafic and ultramafic rocks make them to be the best-suited carbon storage reservoirs in comparison.
A similar assessment for mafic and ultramafic rocks exposed elsewhere in Pakistan, based on their geology, structure, mineral and chemical composition for sequestering CO2 may provide a viable option as another important medium to mitigate the greenhouse gas effect of CO2.
Ahmad, I., Lawrence, R.D., DiPietro, J., 1998. Olistostromal blocks in metamorphosed Saidu melange, Malakand Agency, North Pakistan. In:Hamidullah, S., Lawrence, R.D., Jan, M.Q. (Eds.), Proceedings of the 13th HKT International Workshop. Geological Bulletin University of Peshawar (Special Issue), 31, 1-3. Ahmed, Z., 1988. Bulk-rock chemistry and petrography of the Skhakot-Qila ophiolite, Pakistan. Acta Mineralogica Pakistanica, 4,4-29.
Anczkiewicz, R., Oberli, F., Burg, J.P., Villa, I.M., Gunther, D., Meier, M., 2001. Timing of normal faulting along the Indus Suture in Pakistan Himalaya and a case of major 231Pa/235U initial disequilibrium in zircon. Earth and Planetary Science Letters, 191,101-114.
Coward, M.P., Windley, B.F., Broughton, R.D., Luff, I.W., Petterson, M.G., Pudsey, C.J.,Rex, D.C., Khan, M.A., 1986. Collision tectonics in the NW Himalayas. In: Coward,M.P., Ries, A.C. (Eds.), Collision Tectonics. Geological Society of London Special Publication, 19, 203-219.
DiPietro, J.A., Ahmad, I., Hussain, A., 2008. Cenozoic kinematic history of the Kohistan fault in the Pakistan Himalaya. Geological Society of America Bulletin, 120, 1428-1440.
DiPietro, J.A., Hussain, A., Ahmad, I., Khan, M.A., 2000. The Main Mantle Thrust in Pakistan: its character and extent. In: Khan, M.A., Treloar, P.J., Searle, M.P., Jan, M.Q. (Eds.), Tectonics of the Nanga Parbat Syntaxis and the Western Himalaya. Geological Society of London, Special Publication, 170, 375-393.
Energy Information and Administration, Report, USA, 2010; Retrieved from www.eia.doe.gov/environment.html.
Goff, F., Lackner, K.S., 1998. Carbon dioxide sequestering using ultramafic rocks.Environmental Geoscience, 5, 89-101. Hussain, S.S., Khan, T., Dawood, H., Khan, I.,1984. A note on Kot-Prang Ghar melange and associated mineral occurrences. Geological Bulletin University of Peshawar, 17, 61-68.
Jan, M.Q., Howie, R.A., 1981. The mineralogy and geochemistry of the metamorphosed basic and ultrabasic rocks of the Jijal Complex, Kohistan, NW Pakistan. Journal of Petrology, 22, 85-126.
Jan, M.Q., Windley, B.F., 1990. Chromian spinel- silicate chemistry in ultramafic rocks of the Jijal Complex, Northwest Pakistan. Journal of Petrology, 31, 667-715.
Jonckbloedt, R.C.L., 1997. The Dissolution of Olivine in Acid. A Cost Effective Process for the Elimination of Waste Acids. Unpublished Ph.D. thesis, Utrecht.
Kausar, A.B., Picard, C., Guillot, S., 1998.Evidence for high-temperature-pressure crystallization during early magmatism of the Kohistan arc, Northern Pakistan. In: Hamidullah, S., Lawrence, R.D., Jan, M.Q. (Eds.), Proceedings of the 13th HKT International Workshop. Geological Bulletin University of Peshawar (Special Issue), 31,91-93.
Khan, M.A., Jan, M.Q., Windley, B.F., Tarney, J., Thirlwall, M.F., 1989. The Chilas mafic-ultramafic igneous complex: the root of the Kohistan island arc in the Himalayas of northern Pakistan. In: Malinconico, L.L., Jr.,Lillie, R.J. (Eds.), Tectonics of the Western Himalayas. Geological Society of America Special Paper, 232, 75-94.
Khan, T., Humayoun, M., 1980. Geology of the Shangla-Alpurai area. Unpublished M.Sc. Thesis, University of Peshawar. Kojima, T., Nagamine, A., Ueno, N., Uemiya, S.,1997. Absorption and fixation of carbon dioxide by rock weathering. In: Herzog, H.J.(Ed.), Proceedings of the Third International Conference on Carbon Dioxide Removal, Cambridge, MA, U.S.A. Energy Conversion and Management, 38, 461-466.
Kump, L.R., Brantley, S.L., Arthur, M.A., 2000.Chemical weathering, atmospheric CO2 and climate. Annual Review of Earth and Planetary Sciences, 28, 611-667.
Lackner, K.S., Butt, D.P., Wendt, C.H., 1997.Progress on binding CO2 in mineral substrates. In: Herzog, H.J. (Ed.), Proceedings of the Third International Conference on Carbon Dioxide Removal, Cambridge, MA, U.S.A. Energy Conversion and Management, 38, 259-264.
Lieftink, D.J., 1997. The preparation and characterization of silica from acid treatment of olivine. Unpublished Ph.D. thesis, Utrecht.
Malinconico, L.L., 1982. Structure of the Himalayas suture zone of Pakistan interpreted from gravity and magnetic data. Unpublished Ph.D. thesis, Dartmouth College, Hanover (USA).
Mani, D., Charan, N.S., Kumar, B., 2008.Assessment of carbon dioxide sequestration potential of ultramafic rocks in the greenstone belts of southern India. Current Science, 94, 5-60.
National oceanic and atmospheric administration, Report, 2006. US Department of commerce. Retrieved from www.noaa.gov.Philip, G., Robert, R., Zhong, Y., 2000. CO2 sequestration in USA. 5th International conference on greenhouse gas control technologies, Aug.13-16, Australia.
Pokrovsky, O.S., Schott, J., 1999. Processes at the magnesium-bearing carbonates/solution interface. II. Kinetics and mechanism of magnesite dissolution. Geochimica et Cosmochimica Acta, 63, 881-897.
Schuiling, R.D., Krijgsman, P., 2006. Enhanced Weathering: An effective and cheap tool to sequester CO2. Climatic Change, 74, 349-354. Schuiling, R.D., Van Herk, J., Pietersen, H.S.,1986. A potential process for the neutralization of industrial waste acids by reaction with olivine, Geologie and Mijnbouw, 65, 243-246.
Searle, M.P., Khan, M.A., Jan, M.Q., DiPietro, J.A., Pogue, K.R., Pivnik, D.A., Sercombe, W.J., Izatt, C.N., Blisniuk, P.M., Treloar, P.J., Gaetani, M., Zanchi, A., 1996. Geological map of north Pakistan and adjacent areas of northern Ladakh and Western Tibet, 1:650000.
Sheikh, M.A., 2010. Energy and renewable energy scenario of Pakistan. Renewable and Sustainable Energy Reviews, 14, 354-363.
Tahirkheli, R.A.K., Mattauer, M., Proust, F., Tapponnier, P., 1979. The India-Eurasia suture zone in northern Pakistan: synthesis and interpretation of recent data at plate sacle. In: Farah, A., DeJong, K.A. (Eds.), Geodynamics of Pakistan. Geological Survey of Pakistan, 125-130.
Retrieved from Weir, G.J., White, S.P., Kissling, W.M., 1995. Reservoir storage and containment of greenhouse gases. Energy Conversion and Management, 36, 531-534. www.asianewsnet.net/climate/pdf/pakistan_profile.Accessed on 2nd October, 2011.
Zevenhoven, R., Kohlmann, J., 2001. CO2 sequestration by magnesium silicate mineral carbonation in Finland. In: Second Nordic Minisymposium on Carbon Dioxide Capture and Storage, 26 October, Goteborg. Available at http://www.entek.chalmers.se/~anly/symp/sy mp 2001.html.
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|Author:||Tahirkheli, Tazeem; Bilqees, Rubina; Abbas, S. Muntazir|
|Publication:||Journal of Himalayan Earth Sciences|
|Date:||Jun 30, 2012|
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