Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest ...Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest Guangdong province has extensive basalt, indicating a promising potential for CO_(2) storage through rapid mineralization. However, understanding of the basic geological setting, potential, and mechanisms of CO_(2) mineralization in the basalts of the Leizhou Peninsula is still limited. The mineralization processes associated with CO_(2)storage at two candidate sites in the area are investigated in this paper: Yongshi Farm and Tianyang Basin(of the dried maar lake). Petrography,rock geochemistry, basalt petrophysical properties, and groundwater hydrochemistry analyses are included in the study. Numerical simulation is used to examine the reaction process and its effects. The results show that basalts in the study areas mainly comprise plagioclase, pyroxene, and Fe–Ti oxides, revealing a total volume fraction exceeding 85%. Additionally, small amounts of quartz and fayalite are available, with volume fractions of 5.1% and 1.0%, respectively. The basalts are rich in divalent metal cations, which can form carbonate minerals, with an average of approximately 6.2 moles of metal cations per 1 kg of rock. The groundwater samples have a pH of 7.5–8.2 and are dominated by the Mg–Ca–HCO3 type. The basalts demonstrate a porosity range of 10.9% to 28.8%, with over 70% of interconnected pores. A 20-year geochemical simulation revealed that CO_(2) injection dissolves primary minerals, including anorthite, albite, and diopside, while CO_(2)mineralization dissolves precipitation secondary minerals, such as calcite, siderite, and dolomite. Furthermore, a substantial rise in pH from 7.6to 10.6 is observed in the vicinity of the injected well, accompanied by a slight reduction in porosity from 20% to 19.8%. Additionally, 36.8% of the injected CO_(2) underwent complete mineralization within five years, revealing an increasing percentage of 66.1% if the experimental period is extended to 20 years. The presence of abundant divalent metal cations in basalts and water-bearing permeable rocks in the Leizhou Peninsula supports the potential for mineral carbonation in basalts, as indicated by the geochemical simulation results. Additional research is necessary to identify the factors that influence the CO_(2) mineralization, storage, and sensitivity analysis of basalt in the Leizhou Peninsula.展开更多
Carbon capture, utilization, and storage (CCUS) have garnered extensive attention as a target of carbon neutrality in China. The development trend of international CCUS projects indicates that the cluster construction...Carbon capture, utilization, and storage (CCUS) have garnered extensive attention as a target of carbon neutrality in China. The development trend of international CCUS projects indicates that the cluster construction of CCUS projects is the main direction of future development. The cost reduction potential of CCUS cluster projects has become a significant issue for CCUS stakeholders. To assess the cost reduction potential of CCUS cluster projects, we selected three coal-fired power plants in the coastal area of Guangdong as research targets. We initially assessed the costs of building individual CCUS projects for each plant and subsequently designed a CCUS cluster project for these plants. By comparing individual costs and CCUS cluster project costs, we assessed the cost reduction potential of CCUS cluster projects. The results show that the unit emission reduction cost for each plant with a capacity of 300 million tonnes per year is 392.34, 336.09, and 334.92 CNY/tCO_(2). By building CCUS cluster project, it could save 56.43 CNY/tCO_(2) over the average cost of individual projects (354.45 CNY/tCO_(2)) when the total capture capacity is 9 million tonnes per year (by 15.92%). Furthermore, we conducted a simulation for the scenario of a smaller designed capture capacity for each plant. We found that as the capture scale increases, the cost reduction potential is higher in the future.展开更多
Red mud(RM)is industrial solid waste that severely threatens environmental safety,and its resource utilization is significant both economically and ecologically.The presence of ferric oxides(Fe_(2)O_(3))makes RM poten...Red mud(RM)is industrial solid waste that severely threatens environmental safety,and its resource utilization is significant both economically and ecologically.The presence of ferric oxides(Fe_(2)O_(3))makes RM potential oxygen carriers(OC)for chemical looping combustion(CLC),which is a promising,novel and low-carbon combustion technology.This work examined the CLC performance of two kinds of RM using gaseous and solid fuels.Both Fe_(2)O_(3) and alkali and alkaline-earth metals(AAEM)species within RM enhance carbon conversion during CLC.Nevertheless,the reactivity of original RM is unsatisfactory due to its low oxygen transporting capacity(R_(0),lower than 0.1),carbon conversion(X_(C),less than 0.8),CO_(2) selectivity(Y_(CO_(2)),less than 0.9)and instable performance.Transition metal oxides including CuO and NiO were used to modify the RM through wet impregnation.Both oxides notably improve RM performances,i.e.,X_(C) and Y_(CO_(2)) are notably increased.Still,deteriorations during redox cycles are observed because of particle agglomeration and sintering,especially for the RM modified with NiO.Considering the cost,potential environmental risk and efficacy,CuO is superior to NiO thanks to the enhanced performances of the modified RM-based OC including higher X_(C)(about 0.9),Y_(CO_(2))(approximately 1)and stronger sintering resistance.展开更多
基金funded by the National Natural Science Foundation of China (U1901217)Guangdong Basic and Applied Basic Research Foundation (2021A1515011298)+1 种基金the National Key R&D Program of China (2021YFF0501202)Special Fund of South China Sea Institute of Oceanology of the Chinese Academy of Sciences (SCSIO2023QY06)。
文摘Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest Guangdong province has extensive basalt, indicating a promising potential for CO_(2) storage through rapid mineralization. However, understanding of the basic geological setting, potential, and mechanisms of CO_(2) mineralization in the basalts of the Leizhou Peninsula is still limited. The mineralization processes associated with CO_(2)storage at two candidate sites in the area are investigated in this paper: Yongshi Farm and Tianyang Basin(of the dried maar lake). Petrography,rock geochemistry, basalt petrophysical properties, and groundwater hydrochemistry analyses are included in the study. Numerical simulation is used to examine the reaction process and its effects. The results show that basalts in the study areas mainly comprise plagioclase, pyroxene, and Fe–Ti oxides, revealing a total volume fraction exceeding 85%. Additionally, small amounts of quartz and fayalite are available, with volume fractions of 5.1% and 1.0%, respectively. The basalts are rich in divalent metal cations, which can form carbonate minerals, with an average of approximately 6.2 moles of metal cations per 1 kg of rock. The groundwater samples have a pH of 7.5–8.2 and are dominated by the Mg–Ca–HCO3 type. The basalts demonstrate a porosity range of 10.9% to 28.8%, with over 70% of interconnected pores. A 20-year geochemical simulation revealed that CO_(2) injection dissolves primary minerals, including anorthite, albite, and diopside, while CO_(2)mineralization dissolves precipitation secondary minerals, such as calcite, siderite, and dolomite. Furthermore, a substantial rise in pH from 7.6to 10.6 is observed in the vicinity of the injected well, accompanied by a slight reduction in porosity from 20% to 19.8%. Additionally, 36.8% of the injected CO_(2) underwent complete mineralization within five years, revealing an increasing percentage of 66.1% if the experimental period is extended to 20 years. The presence of abundant divalent metal cations in basalts and water-bearing permeable rocks in the Leizhou Peninsula supports the potential for mineral carbonation in basalts, as indicated by the geochemical simulation results. Additional research is necessary to identify the factors that influence the CO_(2) mineralization, storage, and sensitivity analysis of basalt in the Leizhou Peninsula.
基金the Department of Education of Guangdong Province(No.2021KQNCX143)the National Social Science Foundation of China(Grant No.21AGJ009)the Research Base of Carbon Neutral Finance for Guangdong-Hong Kong-Macao(No.22ATJR03).
文摘Carbon capture, utilization, and storage (CCUS) have garnered extensive attention as a target of carbon neutrality in China. The development trend of international CCUS projects indicates that the cluster construction of CCUS projects is the main direction of future development. The cost reduction potential of CCUS cluster projects has become a significant issue for CCUS stakeholders. To assess the cost reduction potential of CCUS cluster projects, we selected three coal-fired power plants in the coastal area of Guangdong as research targets. We initially assessed the costs of building individual CCUS projects for each plant and subsequently designed a CCUS cluster project for these plants. By comparing individual costs and CCUS cluster project costs, we assessed the cost reduction potential of CCUS cluster projects. The results show that the unit emission reduction cost for each plant with a capacity of 300 million tonnes per year is 392.34, 336.09, and 334.92 CNY/tCO_(2). By building CCUS cluster project, it could save 56.43 CNY/tCO_(2) over the average cost of individual projects (354.45 CNY/tCO_(2)) when the total capture capacity is 9 million tonnes per year (by 15.92%). Furthermore, we conducted a simulation for the scenario of a smaller designed capture capacity for each plant. We found that as the capture scale increases, the cost reduction potential is higher in the future.
基金the National Natural Science Foundation of China(Grants 22178001,21808002,22178002 and 21978003).
文摘Red mud(RM)is industrial solid waste that severely threatens environmental safety,and its resource utilization is significant both economically and ecologically.The presence of ferric oxides(Fe_(2)O_(3))makes RM potential oxygen carriers(OC)for chemical looping combustion(CLC),which is a promising,novel and low-carbon combustion technology.This work examined the CLC performance of two kinds of RM using gaseous and solid fuels.Both Fe_(2)O_(3) and alkali and alkaline-earth metals(AAEM)species within RM enhance carbon conversion during CLC.Nevertheless,the reactivity of original RM is unsatisfactory due to its low oxygen transporting capacity(R_(0),lower than 0.1),carbon conversion(X_(C),less than 0.8),CO_(2) selectivity(Y_(CO_(2)),less than 0.9)and instable performance.Transition metal oxides including CuO and NiO were used to modify the RM through wet impregnation.Both oxides notably improve RM performances,i.e.,X_(C) and Y_(CO_(2)) are notably increased.Still,deteriorations during redox cycles are observed because of particle agglomeration and sintering,especially for the RM modified with NiO.Considering the cost,potential environmental risk and efficacy,CuO is superior to NiO thanks to the enhanced performances of the modified RM-based OC including higher X_(C)(about 0.9),Y_(CO_(2))(approximately 1)and stronger sintering resistance.
