工廠二氧化碳排放量逐漸增加並引起氣候變化及溫室效應，而二氧化碳的捕獲和儲存(CCS)被認為是減緩碳排放的方法之一。當二氧化碳注入地下800公尺以上時，地層的溫度和壓力將達到臨界點，此時的二氧化碳會以超臨界態的方式存在，超臨界二氧化碳同時具有液態高密度和氣態流動性，可以在岩石的孔隙中吸收擴散，使二氧化碳能夠長期儲存在並與大氣隔絕，達到減少大氣中二氧化碳的目的。將二氧化碳注入地層時，二氧化碳將與地下水反應形成碳酸，會和水泥發生化學反應，從而改變水泥的成分並使滲透性上升，此過程稱為碳化(Carbonation)，最終會使得水泥結構強度下降。
根據過去研究發現，適當加入飛灰、高爐礦渣並以水玻璃作為鹼活化劑，可以增加水泥的性能，提高其機械強度，故本研究將高爐礦渣與水玻璃的配比調整為5:1和8：1、將飛灰的含量分別為10%、20%、30%，再放入超臨界環境的反應器中及在大氣中反應0、7、14、28天。
結果表明，以8:1的比例加入高爐礦渣和水玻璃可以改善水泥的性質，這是因為反應過程中所形成的碳酸鈣可以填補水泥的孔隙，降低試體的滲透性，並防止二氧化碳持續侵蝕，從而提高了機械強度。

Factory carbon dioxide emissions are increasing gradually and causing climate change, and CO2 capture and storage are considered to be one of the ways to slow down carbon emissions. When carbon dioxide is injected more than 800 m underground, the temperature and pressure of the stratum will reach the critical point. Supercritical carbon dioxide has a high density of liquid state and fluidity of gas state, which can diffuse and be absorbed in the pores of rocks so that carbon dioxide can last for a long time and be isolated from the atmosphere. In rejecting CO2 into the formation, CO2 will react with the groundwater to form carbonated acid, which chemically reacts with the cement to change the composition of the cement and increase its permeability. It is called carbonation, eventually causing a loss of structural strength in the cement.
Previous studies found that the proper addition of fly ash, slag, and water glass as an alkali activator can increase the properties of cement and improve its mechanical strength, so this research adjust the ratio of slag and water glass to 5:1 and 8:1, then change the content of fly ash to 10%, 20%, and 30% respectively then put into the reactor of a supercritical environment and react in the atmosphere for 0, 7, 14 and 28 days.
The results show that the addition of slag and water glass at the ratio of 8:1 can improve the performance of the cement because the calcium carbonate formed fills the cement's pores, reduces the cement's permeability, and prevents CO2 erosion, thereby improving the mechanical strength.

[1] L. K. Abidoye and D. B. Das, "Carbon Storage in Portland Cement Mortar: Influences of Hydration Stage, Carbonation Time and Aggregate Characteristics," Clean Technologies, pp. 563-580, 2021.
[2] O. D. Bert Metz, Heleen de Coninck,, "IPCC," 2022.
[3] H. d. C. Ogunlade Davidson, Bert Metz, , "IPCC2005."
[4] "IEA," 2022.
[5] "Global Status of CCS Report Global CCS Institute," 2021.
[6] "溫室氣體排放清冊," 2022.
[7] "二氧化碳再利用與地質封存潛能評估計畫," 2007.
[8] 劉浙仁、譚志豪、冀樹勇, "臺灣發展二氧化碳地質封存之場址評選策略研議," 中興工程, no. 131, pp. 19-28, 2016.
[9] T. Andreas Sørbrøden, Tonni Franke ,Johansen,Idar Larsen,, "Laboratory experiments on ulytasonic logging through casing for barrier integrity validation," ASME, 2017.
[10] C. Li, K. N. Zhang, Y. S. Wang, C. B. Guo, and F. Maggi, "Experimental and numerical analysis of reservoir performance for geological CO2 storage in the Ordos Basin in China," International Journal of Greenhouse Gas Control, pp. 216-232, Feb 2016.
[11] E. Keven Silva and M. Angela A. Meireles, "Encapsulation of Food Compounds Using Supercritical Technologies: Applications of Supercritical Carbon Dioxide as an Antisolvent," Food and Public Health, pp. 247-258, 2014.
[12] "臺灣2050淨零排放路徑及策略總說明," 2022.
[13] "World Energy Ootlook 2016," 2016.
[14] M. A. Ken Caldeira, "Ocean storage.pdf."
[15] R. K. Saran, V. Arora, and S. Yadav, "CO2 sequestration by mineral carbonation: a review," Global Nest Journal, pp. 497-503, Dec 2018.
[16] T. P. Irons, B. J. O. L. McPhserson, N. Moodie, R. Krahenbuhl, and Y. Li, "Integrating geophysical monitoring data into multiphase fluid flow reservoir simulation," ASEG Extended Abstracts, pp. 1-5, 2019.
[17] J. R. Brydie et al., "The Development of a Leak Remediation Technology for Potential Non- Wellbore Related Leaks from CO2 Storage Sites," Energy Procedia, pp. 4601-4611, 2014.
[18] O. D. Bert Metz, Heleen de Coninck, Manuela Loos and Leo Meyer, "Carbon dioxide capture and storage," 2005.
[19] S. Gasda, S. Bachu, and M. Celia, "The potential for CO2 leakage from storage sites in geological media: analysis of well distribution in mature sedimentary basins," Environmental Geology, pp. 707-720, 2004.
[20] M. M. Hossain, and M. M. Amro, "Drilling and Completion Challenges and Remedies of CO2 Injected Wells with Emphasis to Mitigate Well Integrity Issues," SPE Asia Pacific Oil and Gas Conference and Exhibition, 2010.
[21] J. W. Carey et al., "Analysis and performance of oil well cement with 30 years Of CO(2) exposure from the SACROC Unit, West Texas, USA," International Journal of Greenhouse Gas Control, pp. 75-85, Apr 2007.
[22] R. K. Haghi, A. Chapoy, L. M. C. Peirera, J. H. Yang, and B. Tohidi, "pH of CO2 saturated water and CO2 saturated brines: Experimental measurements and modelling," International Journal of Greenhouse Gas Control, pp. 190-203, Nov 2017.
[23] S. D. C. Walsh, W. L. Du Frane, H. E. Mason, and S. A. Carroll, "Permeability of Wellbore-Cement Fractures Following Degradation by Carbonated Brine," Rock Mechanics and Rock Engineering, pp. 455-464, May 2013.
[24] A. Duguid and G. W. Scherer, "Degradation of oilwell cement due to exposure to carbonated brine," International Journal of Greenhouse Gas Control, pp. 546-560, May 2010.
[25] M. Bagheri, S. M. Shariatipour, and E. Ganjian, "A review of oil well cement alteration in CO2-rich environments," Construction and Building Materials, pp. 946-968, Oct 2018.
[26] Y. J. Jeong, K. S. Youm, and S. Yun, "Effect of nano-silica and curing conditions on the reaction rate of class G well cement exposed to geological CO2-sequestration conditions," Cement and Concrete Research, pp. 208-216, Jul 2018.
[27] Y. H. Lin et al., "Experimental studies on corrosion of cement in CO2 injection wells under supercritical conditions," Corrosion Science, pp. 13-21, Sep 2013.
[28] N. Moroni, A. Santra, K. Ravi, and W. Hunter., "Holistic Design of Cement Systems to Survive CO2 Environment," SPE Annual Technical Conference and Exhibition, 2009.
[29] M. Zhang and S. Talman, "Experimental Study of Well Cement Carbonation under Geological Storage Conditions," Energy Procedia, pp. 5813-5821, 2014.
[30] Cristina Aiex et al., "An Experimental Study on Effects of Static CO2 on Cement under
High-Pressure/High-Temperature Conditions," Offshore Technology Conference, 2015.
[31] A. Lorek, M. Labus, and P. Bujok, "Wellbore cement degradation in contact zone with formation rock," Environmental Earth Sciences, Mar 2016, Art no. 499.
[32] B. L. D. Costa, J. C. D. Freitas, P. H. S. Santos, R. G. D. Araujo, J. F. D. Oliveira, and D. M. D. Melo, "Study of carbonation in a class G Portland cement matrix at supercritical and saturated environments," Construction and Building Materials, pp. 308-319, Aug 2018.
[33] V. Barlet-Gouédard et al., "Mitigation Strategies for the Risk of CO2 Migration Through Wellbores," 2006.
[34] M. Lesti, C. Tiemeyer, and J. Plank, "CO2 stability of Portland cement based well cementing systems for use on carbon capture & storage (CCS) wells," Cement and Concrete Research, pp. 45-54, Mar 2013.
[35] A. A. M. S. Elkatatny, "Effect of the Temperature on the Strength of NC-Based Cement under GCS," Amarican association of drilling engineers, 2019.
[36] A. A. Mahmoud and S. Elkatatny, "Improved durability of Saudi Class G oil-well cement sheath in CO2 rich environments using olive waste," Construction and Building Materials, Nov 2020, Art no. 120623.
[37] L. K. Turner and F. G. Collins, "Carbon dioxide equivalent (CO2-e) emissions: A comparison between geopolymer and OPC cement concrete," Construction and Building Materials, pp. 125-130, Jun 2013.
[38] J. Davidovits, "Geopolymers-Inorganic polimeric new materials," Journal of Thermal Analysis, pp. 1633-1656, Aug 1991.
[39] H. Xu and J. S. J. Van Deventer, "The geopolymerisation of alumino-silicate minerals," International Journal of Mineral Processing, pp. 247-266, Jun 2000.
[40] P. Rovnanik, "Effect of curing temperature on the development of hard structure of metakaolin-based geopolymer," Construction and Building Materials, pp. 1176-1183, Jul 2010.
[41] P. Duxson, A. Fernandez-Jimenez, J. L. Provis, G. C. Lukey, A. Palomo, and J. S. J. van Deventer, "Geopolymer technology: the current state of the art," Journal of Materials Science, pp. 2917-2933, May 2007.
[42] H. S. Hassan, H. A. Abdel-Gawwad, S. R. V. Garcia, and I. Israde-Alcantara, "Fabrication and characterization of thermally-insulating coconut ash-based geopolymer foam," Waste Management, pp. 235-240, Oct 2018.
[43] S. Adjei, S. Elkatatny, W. N. Aggrey, and Y. Abdelraouf, "Geopolymer as the future oil-well cement: A review," Journal of Petroleum Science and Engineering, Jan 2022, Art no. 109485.
[44] C. Y. Heah et al., "Study on solids-to-liquid and alkaline activator ratios on kaolin-based geopolymers," Construction and Building Materials, pp. 912-922, Oct 2012.
[45] F. H. A. Zaidi et al., "Geopolymer as underwater concreting material: A review," Construction and Building Materials, Jul 2021, Art no. 123276.
[46] S. M. Laskar and S. Talukdar, "Preparation and tests for workability, compressive and bond strength of ultra-fine slag based geopolymer as concrete repairing agent," Construction and Building Materials, pp. 176-190, Nov 2017.
[47] K. T. Wang, L. Q. Du, X. S. Lv, Y. He, and X. M. Cui, "Preparation of drying powder inorganic polymer cement based on alkali-activated slag technology," Powder Technology, pp. 204-209, May 2017.
[48] R. R. Suppiah, S. H. A. Rahman, N. Shafiq, and S. Irawan, "Uniaxial compressive strength of geopolymer cement for oil well cement," Journal of Petroleum Exploration and Production Technology, pp. 67-70, Jan 2020.
[49] S. Ridha, A. I. Abd Hamid, and C. Mazuan, "Influence of different brine water salinity on mechanical properties of fly ash-based geopolymer cement," International Journal of Structural Integrity, pp. 142-152, 2018.
[50] R. B. Ledesma et al., "Zeolite and fly ash in the composition of oil well cement: Evaluation of degradation by CO2 under geological storage condition," Journal of Petroleum Science and Engineering, Feb 2020.
[51] A. G. D. Azevedo and K. Strecker, "Brazilian fly ash based inorganic polymers production using different alkali activator solutions," Ceramics International, pp. 9012-9018, Aug 2017.
[52] 李冠穎, "二氧化碳環境下對油井水泥物理性質及化學性質之影響," 國立成功大學, 臺灣博碩士論文知識加值系統, 2011.
[53] 江健豪, "超臨界二氧化碳環境下對套管水泥力學與物化性質之影響," 國立成功大學, 臺灣博碩士論文知識加值系統, 2012.
[54] 陳思螢, "超臨界二氧化碳環境下對套管水泥斷裂韌度影響之研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2012.
[55] 陳宏銓, "超臨界二氧化碳環境下對添加矽酸化合物套管水泥性質之研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2014.
[56] 郭俊志, "二氧化碳封存環境下對封固材料基本性質影響之研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2016.
[57] 謝欣婷, "超臨界二氧化碳環境下對添加碳化矽套管水泥力學與物化性質之研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2016.
[58] 林唐筠, "臨界二氧化碳環境下添加不同鈣矽比摻料對套管水泥力學、物理與化學性質之研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2017.
[59] 許真惠, "超臨界二氧化碳環境下對添加碳化矽之套管水泥基本性質之研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2018.
[60] 黃卉宇, "不同溫度及壓力的超臨界二氧化碳環境下含碳化矽及二氧化矽之套管水泥性質研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2020.
[61] 張孟哲, "超臨界二氧化碳環境下添加聚丙烯纖維及含矽材料之套管水泥性質研究," 國立成功大學, 臺灣博碩士論文知識加值系統, 2022.