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Journal of Earth Science

, Volume 28, Issue 3, pp 457–472 | Cite as

Reactive transport modeling of long-term CO2 sequestration mechanisms at the Shenhua CCS demonstration project, China

  • Guodong Yang
  • Yilian LiEmail author
  • Aleks Atrens
  • Danqing Liu
  • Yongsheng Wang
  • Li Jia
  • Yu Lu
Experimental Geochemistry and Computational Geochemistry

Abstract

Carbon dioxide injection into deep saline aquifers results in a variety of strongly coupled physical and chemical processes. In this study, reactive transport simulations using a 2-D radial model were performed to investigate the fate of the injected CO2, the effect of CO2-water-rock interactions on mineral alteration, and the long-term CO2 sequestration mechanisms of the Liujiagou Formation sandstone at the Shenhua CCS (carbon capture and storage) pilot site of China. Carbon dioxide was injected at a constant rate of 0.1 Mt/year for 30 years, and the fluid flow and geochemical transport simulation was run for a period of 10 000 years by the TOUGHREACT code according to the underground conditions of the Liujiagou Formation. The results show that different trapping phases of CO2 vary with time. Sensitivity analyses indicate that plagioclase composition and chlorite presence are the most significant determinants of stable carbonate minerals and CO2 mineral trapping capacity. For arkosic arenite in the Liujiagou Formation, CO2 can be immobilized by precipitation of ankerite, magnesite, siderite, dawsonite, and calcite for different mineral compositions, with Ca2+, Mg2+, Fe2+ and Na+ provided by dissolution of calcite, albite (or oligoclase) and chlorite. This study can provide useful insights into the geochemistry of CO2 storage in other arkosic arenite (feldspar rich sandstone) formations at other pilots or target sites.

Key words

carbon capture and storage (CCS) CO2 sequestration geochemical interaction mineral trapping CCS demonstration project reactive transport modeling 

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Notes

Acknowledgments

This work was partially supported by the Global Climate and Energy Project (No. 2384638-43106-A), the National Natural Science Foundation of China (No. 41072180), the Special Scientific Research Fund of Public Welfare Profession of the Ministry of Land and Resources of China (No. 201211063), and a bilateral project of China Australia Geological Storage of CO2 Project Phase 2 (CAGS2). We would like to thank Dr. Sizhen Peng, Jiutian Zhang (The Administrative Centre for China’s Agenda 21) and Maoshan Chen (The Shenhua Group Corporation Limited) for their insightful suggestions on the manuscript. Two anonymous reviewers are also gratefully acknowledged. The final publication is available at Springer via http://dx.doi.org/10.1007/s12583-016-0919-6.

References

  1. Amin, S. M., Weiss, D. J., Blunt, M. J., 2014. Reactive Transport Modelling of Geologic CO2 Sequestration in Saline Aquifers: The Influence of Pure CO2 and of Mixtures of CO2 with CH4 on the Sealing Capacity of Cap Rock at 37 °C and 100 bar. Chemical Geology, 367: 39–50. doi:10.1016/j.chemgeo.2014.01.002CrossRefGoogle Scholar
  2. André, L., Audigane, P., Azaroual, M., et al., 2007. Numerical Modeling of Fluid-Rock Chemical Interactions at the Supercritical CO2-Liquid Interface during CO2 Injection into a Carbonate Reservoir, the Dogger Aquifer (Paris Basin, France). Energy Conversion and Management, 48(6): 1782–1797. doi:10.1016/j.enconman.2007.01.006CrossRefGoogle Scholar
  3. Assayag, N., Matter, J., Ader, M., et al., 2009. Water-Rock Interactions during a CO2 Injection Field-Test: Implications on Host Rock Dissolution and Alteration Effects. Chemical Geology, 265(1–2): 227–235. doi:10.1016/j.chemgeo.2009.02.007CrossRefGoogle Scholar
  4. Bacci, G., Korre, A., Durucan, S., 2011. An Experimental and Numerical Investigation into the Impact of Dissolution/Precipitation Mechanisms on CO2 Injectivity in the Wellbore and Far Field Regions. International Journal of Greenhouse Gas Control, 5(3): 579–588. doi:10.1016/j.ijggc.2010.05.007CrossRefGoogle Scholar
  5. Bachu, S., 2000. Sequestration of CO2 in Geological Media: Criteria and Approach for Site Selection in Response to Climate Change. Energy Conversion and Management, 41(9): 953–970. doi:10.1016/s0196-8904(99)00149-1CrossRefGoogle Scholar
  6. Balashov, V. N., Guthrie, G. D., Hakala, J. A., et al., 2013. Predictive Modeling of CO2 Sequestration in Deep Saline Sandstone Reservoirs: Impacts of Geochemical Kinetics. Applied Geochemistry, 30(2): 41–56. doi:10.1016/j.apgeochem.2012.08.016CrossRefGoogle Scholar
  7. Bertier, P., Swennen, R., Laenen, B., et al., 2006. Experimental Identification of CO2-Water-Rock Interactions Caused by Sequestration of CO2 in Westphalian and Buntsandstein Sandstones of the Campine Basin (NE-Belgium). Journal of Geochemical Exploration, 89(1–3): 10–14. doi:10.1016/j.gexplo.2005.11.005CrossRefGoogle Scholar
  8. British Petroleum (BP), 2010. BP Statistical Review of World Energy 2010. BP Plc, British China Shenhua Coal to Liquid Chemical Engineering Company, 2014. The Operation Report of the Shenhua 0.1 Mt CCS Demonstration Project, Ordos (in Chinese)Google Scholar
  9. Corey, A. T., 1954. The Interrelation between Gas and Oil Relative Permeabilities. Producers Monthly, 19(1): 38–41Google Scholar
  10. Credoz, A., Bildstein, O., Jullien, M., et al., 2009. Experimental and Modeling Study of Geochemical Reactivity between Clayey Caprocks and CO2 in Geological Storage Conditions. Energy Procedia, 1(1): 3445–3452. doi:10.1016/j.egypro.2009.02.135CrossRefGoogle Scholar
  11. Eiken, O., Ringrose, P., Hermanrud, C., et al., 2011. Lessons Learned from 14 Years of CCS Operations: Sleipner, in Salah and Snøhvit. Energy Procedia, 4: 5541–5548. doi:10.1016/j.egypro.2011.02.541CrossRefGoogle Scholar
  12. Gaus, I., Audigane, P., André, L., et al., 2008. Geochemical and Solute Transport Modelling for CO2 Storage, What to Expect from It?. International Journal of Greenhouse Gas Control, 2(4): 605–625. doi:10.1016/j.ijggc.2008.02.011CrossRefGoogle Scholar
  13. Gaus, I., Azaroual, M., Czernichowski-Lauriol, I., 2005. Reactive Transport Modelling of the Impact of CO2 Injection on the Clayey Cap Rock at Sleipner (North Sea). Chemical Geology, 217(3–4): 319–337. doi:10.1016/j.chemgeo.2004.12.016CrossRefGoogle Scholar
  14. Goddéris, Y., Williams, J. Z., Schott, J., et al., 2010. Time Evolution of the Mineralogical Composition of Mississippi Valley Loess over the Last 10 kyr: Climate and Geochemical Modeling. Geochimica et Cosmochimica Acta, 74(22): 6357–6374. doi:10.1016/j.gca.2010.08.023CrossRefGoogle Scholar
  15. Goodarzi, S., Settari, A., Keith, D., 2012. Geomechanical Modeling for CO2 Storage in Nisku Aquifer in Wabamun Lake Area in Canada. International Journal of Greenhouse Gas Control, 10(10): 113–122. doi:10.1016/j.ijggc.2012.05.020CrossRefGoogle Scholar
  16. Hellevang, H., Aagaard, P., Oelkers, E. H., et al., 2005. Can Dawsonite Permanently Trap CO2?. Environmental Science & Technology, 39(21): 8281–8287. doi:10.1021/es0504791CrossRefGoogle Scholar
  17. Hermanrud, C., Andresen, T., Eiken, O., et al., 2009. Storage of CO2 in Saline Aquifers-Lessons Learned from 10 Years of Injection into the Utsira Formation in the Sleipner Area. Energy Procedia, 1(1): 1997–2004. doi:10.1016/j.egypro.2009.01.260CrossRefGoogle Scholar
  18. Hou, G. C., Zhang, M. S., Liu, F., 2008. The Ordos Basin Groundwater Investigation Research. Geological Publishing House, Beijing (in Chinese)Google Scholar
  19. IEA, 2008. CO2 Capture and Storage: A Key Carbon Abatement Option. OECD Publishing, Paris. doi:10.1787/9789264041417-enGoogle Scholar
  20. IPCC, 2005. IPCC Special Report on Carbon Dioxide Capture and Storage. Prepared by Working Group III of the Intergovernmental Panel on Climate Change. In: Metz, B., Davidson, O., de Coninck, H. C., et al., eds., Cambridge University Press, Cambridge. 442Google Scholar
  21. Izgec, O., Demiral, B., Bertin, H., et al., 2008. CO2 Injection into Saline Carbonate Aquifer Formations II: Comparison of Numerical Simulations to Experiments. Transport in Porous Media, 73(1): 57–74. doi:10.1007/s11242-007-9160-1CrossRefGoogle Scholar
  22. Kampman, N., Bickle, M., Wigley, M., et al., 2014. Fluid Flow and CO2-Fluid-Mineral Interactions during CO2-Storage in Sedimentary Basins. Chemical Geology, 369(14): 22–50. doi:10.1016/j.chemgeo.2013.11.012CrossRefGoogle Scholar
  23. Kharaka, Y. K., Cole, D. R., Hovorka, S. D., et al., 2006. Gas-Water-Rock Interactions in Frio Formation Following CO2 Injection: Implications for the Storage of Greenhouse Gases in Sedimentary Basins. Geology, 34(7): 577–580. doi:10.1130/g22357a.1CrossRefGoogle Scholar
  24. Kharaka, Y. K., Thordsen, J. J., Hovorka, S. D., et al., 2009. Potential Environmental Issues of CO2 Storage in Deep Saline Aquifers: Geochemical Results from the Frio-I Brine Pilot Test, Texas, USA. Applied Geochemistry, 24(6): 1106–1112. doi:10.1016/j.apgeochem.2009.02.010CrossRefGoogle Scholar
  25. Kihm, J. H., Kim, J. M., Wang, S., et al., 2012. Hydrogeochemical Numerical Simulation of Impacts of Mineralogical Compositions and Convective Fluid Flow on Trapping Mechanisms and Efficiency of Carbon Dioxide Injected into Deep Saline Sandstone Aquifers. Journal of Geophysical Research: Solid Earth, 117(B6): 6204. doi:10.1029/2011jb008906CrossRefGoogle Scholar
  26. Li, D. S., 2004. Return to Petroleum Geology of Ordos Basin. Petroleum Exploration & Development, 31(6): 1–7 (in Chinese with English Abstract)Google Scholar
  27. Li, Q., Liu, G. Z., Liu, X. H., et al., 2013. Application of a Health, Safety, and Environmental Screening and Ranking Framework to the Shenhua CCS Project. International Journal of Greenhouse Gas Control, 17(5): 504–514. doi:10.1016/j.ijggc.2013.06.005CrossRefGoogle Scholar
  28. Li, X. Q., Hou, D. J., Hu, G. Y., 2005. Formation Fluid Characteristics and Gas Accumulation of the Central Gas Field of Ordos Basin. Geological Publishing House, Beijing (in Chinese)Google Scholar
  29. Liu, H. J., Hou, Z. M., Were, P., et al., 2015. Modelling CO2-Brine-Rock Interactions in the Upper Paleozoic Formations of Ordos Basin Used for CO2 Sequestration. Environmental Earth Sciences, 73(5): 2205–2222. doi:10.1007/s12665-014-3571-4CrossRefGoogle Scholar
  30. Liu, N. N., Liu, L., Ming, X. R., et al., 2014. Petrologic and Geochemical Characteristics and Carbon Sequestration Capability of the Permian Shiqianfeng Formation around Ejin Horo Banner of Ordos Basin. Acta Petrologica et Mineralogica, 33(2): 255–262 (in Chinese with English Abstract)Google Scholar
  31. Liu, N., Liu, L., Qu, X. Y., et al., 2011. Genesis of Authigene Carbonate Minerals in the Upper Cretaceous Reservoir, Honggang Anticline, Songliao Basin: A Natural Analog for Mineral Trapping of Natural CO2 Storage. Sedimentary Geology, 237(3/4): 166–178. doi:10.1016/j.sedgeo.2011.02.012CrossRefGoogle Scholar
  32. Lu, J. M., Kharaka, Y. K., Thordsen, J. J., et al., 2012. CO2-Rock-Brine Interactions in Lower Tuscaloosa Formation at Cranfield CO2 Sequestration Site, Mississippi, U.S.A.. Chemical Geology, 291(1): 269–277. doi:10.1016/j.chemgeo.2011.10.020CrossRefGoogle Scholar
  33. Lu, J., Kordi, M., Hovorka, S. D., et al., 2013. Reservoir Characterization and Complications for Trapping Mechanisms at Cranfield CO2 Injection Site. International Journal of Greenhouse Gas Control, 18(7): 361–374. doi:10.1016/j.ijggc.2012.10.007CrossRefGoogle Scholar
  34. Lu, P., Fu, Q., Seyfried, W. E., et al., 2011. Navajo Sandstone-Brine-CO2 Interaction: Implications for Geological Carbon Sequestration. Environmental Earth Sciences, 62(1): 101–118. doi:10.1007/s12665-010-0501-yCrossRefGoogle Scholar
  35. Luengen, H. B., Endemann, G., Schmö le, P., 2011. Measures to Reduce CO2 and Other Emissions in the Steel Industry in Germany and Europe. World Iron & Steel, 16(5): 42–50Google Scholar
  36. Mitiku, A. B., Li, D., Bauer, S., et al., 2013. Geochemical Modelling of CO2-Water-Rock Interactions in a Potential Storage Formation of the North German Sedimentary Basin. Applied Geochemistry, 36(3): 168–186. doi:10.1016/j.apgeochem.2013.06.008CrossRefGoogle Scholar
  37. Moore, J., Adams, M., Allis, R., et al., 2005. Mineralogical and Geochemical Consequences of the Long-Term Presence of CO2 in Natural Reservoirs: An Example from the Springerville-St. Johns Field, Arizona, and New Mexico, U.S.A.. Chemical Geology, 217(3/4): 365–385. doi:10.1016/j.chemgeo.2004.12.019Google Scholar
  38. Oelkers, E. H., Gislason, S. R., Matter, J., 2008. Mineral Carbonation of CO2. Elements, 4(5): 333–337. doi:10.2113/gselements.4.5.333CrossRefGoogle Scholar
  39. Okuyama, Y., Todaka, N., Sasaki, M., et al., 2013. Reactive Transport Simulation Study of Geochemical CO2 Trapping on the Tokyo Bay Model–With Focus on the Behavior of Dawsonite. Applied Geochemistry, 30(2): 57–66. doi:10.1016/j.apgeochem.2012.07.009CrossRefGoogle Scholar
  40. Olajire, A. A., 2013. A Review of Mineral Carbonation Technology in Sequestration of CO2. Journal of Petroleum Science and Engineering, 109: 364–392. doi:10.1016/j.petrol.2013.03.013CrossRefGoogle Scholar
  41. Petroleum Geology Group of Oilfield, 1992. Petroleum Geology of China (Vol. 12) Changqing Oil Field. Petroleum Industry Press, Beijing. 490 (in Chinese)Google Scholar
  42. Rosenbauer, R. J., Koksalan, T., Palandri, J. L., 2005. Experimental Investigation of CO2-Brine-Rock Interactions at Elevated Temperature and Pressure: Implications for CO2 Sequestration in Deep-Saline Aquifers. Fuel Processing Technology, 86(14/15): 1581–1597. doi:10.1016/j.fuproc.2005.01.011CrossRefGoogle Scholar
  43. Tambach, T. J., Koenen, M., Wasch, L. J., et al., 2015. Geochemical Evaluation of CO2 Injection and Containment in a Depleted Gas Field. International Journal of Greenhouse Gas Control, 32: 61–80. doi:10.1016/j.ijggc.2014.10.005CrossRefGoogle Scholar
  44. Thomas, M. W., Stewart, M., Trotz, M., et al., 2012. Geochemical Modeling of CO2 Sequestration in Deep, Saline, Dolomitic-Limestone Aquifers: Critical Evaluation of Thermodynamic Sub-Models. Chemical Geology, 306/307: 29–39. doi:10.1016/j.chemgeo.2012.02.019Google Scholar
  45. Trémosa, J., Castillo, C., Vong, C. Q., et al., 2014. Long-Term Assessment of Geochemical Reactivity of CO2 Storage in Highly Saline Aquifers: Application to Ketzin, In Salah and Snøhvit Storage Sites. International Journal of Greenhouse Gas Control, 20: 2–26. doi:10.1016/j.ijggc.2013.10.022CrossRefGoogle Scholar
  46. van Genuchten, M. T. V., 1980. A Closed-Form Equation for Predicting the Hydraulic Conductivity of Unsaturated Soils. Soil Science Society of America Journal, 44(5): 892–898. doi:10.2136/sssaj1980.03615995004400050002xCrossRefGoogle Scholar
  47. Wang, H. Y., 2012. Study on the Interaction of CO2 Fluid with Sandstone in Shiqianfeng: [Dissertation]. Jilin University, Changchun (in Chinese with English Abstract)Google Scholar
  48. Wang, L., Shen, Z. L., Hu, L. S., et al., 2014. Modeling and Measurement of CO2 Solubility in Salty Aqueous Solutions and Application in the Erdos Basin. Fluid Phase Equilibria, 377: 45–55. doi:10.1016/j.fluid.2014.06.016CrossRefGoogle Scholar
  49. Wang, Y. S., 2014. The Research Report of the Shenhua 0.1 Mt CCS Demonstration Project. China Shenhua Coal Liquefaction Co., Ltd., Ordos. Unpulished Results (in Chinese)Google Scholar
  50. Wang, Y., Crandall, D., Bruner, K., et al., 2013. Core and Pore Scale Characterization of Liujiagou Outcrop Sandstone, Ordos Basin, China for CO2 Aquifer Storage. Energy Procedia, 37: 5055–5062. doi:10.1016/j.egypro.2013.06.419CrossRefGoogle Scholar
  51. Watson, M. N., Zwingmann, N., Lemon, N. M., 2004. The Ladbroke Grove-Katnook Carbon Dioxide Natural Laboratory: A Recent CO2 Accumulation in a Lithic Sandstone Reservoir. Energy, 29(9/10): 1457–1466. doi:10.1016/j.energy.2004.03.079CrossRefGoogle Scholar
  52. White, S. P., Allis, R. G., Moore, J., et al., 2005. Simulation of Reactive Transport of Injected CO2 on the Colorado Plateau, Utah, U.S.A.. Chemical Geology, 217(3/4): 387–405. doi:10.1016/j.chemgeo.2004.12.020CrossRefGoogle Scholar
  53. Whittaker, S., Rostron, B., Hawkes, C., et al., 2011. A Decade of CO2 Injection into Depleting Oil Fields: Monitoring and Research Activities of the IEA GHG Weyburn-Midale CO2 Monitoring and Storage Project. Energy Procedia, 4: 6069–6076. doi:10.1016/j.egypro.2011.02.612CrossRefGoogle Scholar
  54. Wigand, M., Carey, J. W., Schü tt, H., et al., 2008. Geochemical Effects of CO2 Sequestration in Sandstones under Simulated In-Situ Conditions of Deep Saline Aquifers. Applied Geochemistry, 23(9): 2735–2745. doi:10.1016/j.apgeochem.2008.06.006CrossRefGoogle Scholar
  55. Wolery, T. J., 1992. Software Package for Geochemical Modeling of Aqueous System: Package Overview and Installation Guide (Version 8.0). Lawrence Livermore National Laboratory Report UCRL-MA-110662 PT I, Livermore, California, U.S.A.CrossRefGoogle Scholar
  56. Wu, X. Z., 2013. Carbon Dioxide Capture and Geological Storage: The First Massive Exploration in China. Science Press, Beijing (in Chinese)Google Scholar
  57. Xie, H. P., Li, X. C., Fang, Z. M., et al., 2014. Carbon Geological Utilization and Storage in China: Current Status and Perspectives. Acta Geotechnica, 9(1): 7–27. doi:10.1007/s11440013-0277-9CrossRefGoogle Scholar
  58. Xu, T. F., Apps, J. A., Pruess, K., 2004. Numerical Simulation of CO2 Disposal by Mineral Trapping in Deep Aquifers. Applied Geochemistry, 19(6): 917–936. doi:10.1016/j.apgeochem.2003.11.003CrossRefGoogle Scholar
  59. Xu, T. F., Kharaka, Y. K., Doughty, C., et al., 2010. Reactive Transport Modeling to Study Changes in Water Chemistry Induced by CO2 Injection at the Frio-I Brine Pilot. Chemical Geology, 271(3/4): 153–164. doi:10.1016/j.chemgeo.2010.01.006CrossRefGoogle Scholar
  60. Xu, T. F., Apps, J. A., Pruess, K., 2005. Mineral Sequestration of Carbon Dioxide in a Sandstone-Shale System. Chemical Geology, 217(3/4): 295–318. doi:10.1016/j.chemgeo.2004.12.015CrossRefGoogle Scholar
  61. Xu, T. F., Sonnenthal, E., Spycher, N., et al., 2006. TOUGHREACT—A Simulation Program for Non-Isothermal Multiphase Reactive Geochemical Transport in Variably Saturated Geologic Media: Applications to Geothermal Injectivity and CO2 Geological Sequestration. Computers & Geosciences, 32(2): 145–165. doi:10.1016/j.cageo.2005.06.014CrossRefGoogle Scholar
  62. Xu, T. F., Spycher, N., Sonnenthal, E., et al., 2012. TOUGHREACT User’s Guide: A Simulation Program for Non-Isothermal Multiphase Reactive Transport in Variably Saturated Geologic Media, Version 2.0. Earth Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA94720Google Scholar
  63. Yang, G. D., Li, Y. L., Cheng, P., et al., 2011. Assessment of CO2 Geological Storage Potential of Some Sedimentary Basins in China (Poster). 2011 GCEP Research Symposium: Addressing the Changing Energy Landscape. Stanford University, StanfordGoogle Scholar
  64. Yang, G. D., Li, Y. L., Ma, X., et al., 2014. Effect of Chlorite on CO2-Water-Rock Interaction. Earth Science–Journal of China University of Geosciences, 39(4): 462–472. doi:10.3799/dqkx.2014.044 (in Chinese with English Abstract)CrossRefGoogle Scholar
  65. Zhang, S., DePaolo, D. J., Xu, T. F., et al., 2013. Mineralization of Carbon Dioxide Sequestered in Volcanogenic Sandstone Reservoir Rocks. International Journal of Greenhouse Gas Control, 18: 315–328. doi:10.1016/j.ijggc.2013.08.001CrossRefGoogle Scholar
  66. Zhang, W., Li, Y. L., Xu, T. F., et al., 2009. Long-Term Variations of CO2 Trapped in Different Mechanisms in Deep Saline Formations: A Case Study of the Songliao Basin, China. International Journal of Greenhouse Gas Control, 3(2): 161–180. doi:10.1016/j.ijggc.2008.07.007CrossRefGoogle Scholar
  67. Zhao, R. R., Cheng, J. M., 2016. Using Hydraulic Barrier Control CO2 Plume Migration in Sloping Reservoir. Earth Science–Journal of China University of Geosciences, 41(4): 675–682 (in Chinese with English Abstract)CrossRefGoogle Scholar
  68. Zhu, H. T., Liu, K. Y., Yang, X. H., et al., 2013. Sedimentary Controls on the Sequence Stratigraphic Architecture in Intra-Cratonic Basins: An Example from the Lower Permian Shanxi Formation, Ordos Basin, Northern China. Marine and Petroleum Geology, 45: 42–54. doi:10.1016/j.marpetgeo.2013.04.0CrossRefGoogle Scholar

Copyright information

© China University of Geosciences and Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Guodong Yang
    • 1
  • Yilian Li
    • 1
    Email author
  • Aleks Atrens
    • 2
  • Danqing Liu
    • 1
  • Yongsheng Wang
    • 3
  • Li Jia
    • 4
  • Yu Lu
    • 1
  1. 1.School of Environmental StudiesChina University of GeosciencesWuhanChina
  2. 2.The Queensland Geothermal Energy Centre of Excellence, School of Mechanical and Mining EngineeringThe University of QueenslandSt LuciaAustralia
  3. 3.China Shenhua Coal Liquefaction Co, Ltd. OrdosOrdosChina
  4. 4.The Administrative Center for China’s Agenda 21BeijingChina

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