APPLIED ENERGY
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2024
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IF 10.1
Caili Li,Yingjie Li,Yi Fang,Chunxiao Zhang,Yu Ren
CaO-CaCO 3 thermochemical energy storage is a promising technology for solar energy utilization and storage. Alkaline papermaking waste (APW) from paper mills, which is mainly composed of CaCO 3 . Herein, TiO 2 /MnFe 2 O 4 co-modified APW was synthesized. The energy storage capacity of TiO 2 /MnFe 2 O 4 co-modified APW was studied during CaO-CaCO 3 thermochemical energy storage cycles in a duel fixed bed reactor. TiO 2 /MnFe 2 O 4 co-modified APW mainly consists of CaO, MgO, CaTiO 3 , CaMnO 3 , and Ca 2 Fe 2 O 5 . The introductions of TiO 2 and MnFe 2 O 4 significantly improve the cyclic stability and optical absorption property of APW in 30 cycles. The co-modified APW (the mass ratio for CaO:TiO 2 :MnFe 2 O 4 = 100:5:5) possesses high sintering resistance, energy storage, and optical absorption capacities in 30 cycles. The energy storage conversion and capacity of the co-modified APW are 0.72 and 2288.57 kJ/kg after 30 cycles, respectively. The optical absorptance of the co-modified APW reaches 49%, which is 9.25 times as high as that of APW. CaTiO 3 and CaMnO 3 effectively mitigate the sintering of CaO grains. CaMnO 3 and Ca 2 Fe 2 O 5 significantly increase the optical absorptance of APW. The co-modified APW possesses stronger basicity and more oxygen vacancies, which is favourable for the carbonation reaction. Thus, TiO 2 /MnFe 2 O 4 co-modified APW is a good energy storage material.
研究领域:
材料科学
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能源存储
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化学工程
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Zhu-yu Li,Le-ran Li,Sheng Li,Ding-can Wang,Qi Niu,Kai Li,Ji Liu,Qiang Lu
Calcium-based thermochemical heat storage (TCHS) is an economical and environmentally friendly technology for efficient heat storage. It can strengthen the flexibility in power systems of renewable energy and promote the recovery and storage of waste heat in energy-intensive industries. However, CaO/CaCO 3 is extremely prone to sintering at operational temperatures. Consequently, a cost-effective approach was proposed to synthesize calcium-based TCHS materials modified by pyroligneous acid (PA) impregnation and co-doping with dual transition metals. The heat storage performance, physicochemical property, and anti-sintering mechanism of synthesized CaO were comparatively examined. The sample prepared with a molar ratio of Ca: Co: Mn = 100:3:7 (PACa-Co3Mn7) exhibited an initial energy storage density of 1.76 MJ/kg, which gradually rose to 1.88 MJ/kg. After 20 cycles, the value decreased by only 4.39 % from its peak, indicating outstanding TCHS performance. Characterization results indicated that the specific surface area and pore volume of PACa-Co3Mn7 were 10.48 m 2 /g and 0.035 cm 3 /g, which were 2.34 and 2.69 times those of CaO stemmed from the calcination of limestone, respectively. The fruitful pores provided pathways for CO 2 diffusion within the CaO particles or CaCO 3 product layer. The uniformly distributed Co and Mn elements combined to form Ca 3 CoMnO 6 . Ca 3 CoMnO 6 could serve as the inert carrier that mitigated the grain-growth of CaO, thereby stabilizing the pore structure and resisting the sintering of PACa-Co3Mn7. Furthermore, density functional theory (DFT) calculations demonstrated that the free Mn and Co elements efficiently promoted the electrons transfer between CaO and CO 2 , which improved the reactivity of PACa-Co3Mn7. Therefore, CaO modified by PA impregnation and co-doping with dual transition metal is a promising candidate for the TCHS system.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
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2024
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IF 8.9
Yi Fang,Yingjie Li,Youhao Zhang,Yuzhuo Wang,Zirui He,Kuihua Han,Jun Jie Wu
CaO/CaCO 3 energy storage is a promising technology to solve the intermittency of solar energy. Fluidized-bed reactors serve as crucial devices for calcination and carbonation in CaO/CaCO 3 energy storage system . This work presents the first observation of defluidization occurring in CaO/CaCO 3 energy storage process. The mechanism of defluidization was investigated through the exothermic experiment and computational fluid dynamics-discrete element method. Furthermore, the defluidization in the exothermic stage was mitigated by simultaneous nano-silica coating and SiO 2 fines addition. The result indicates that high CO 2 concentration (>80 %), small particle size (0.075–0.18 mm) and low initial bed temperature (700–800 °C) result in the defluidization. The defluidization leads to low exothermic performance of CaO particles and serious uneven temperature distribution in the exothermic stage during CaO/CaCO 3 energy storage process. The simulation result indicates that carbonation proceeding at zero-order kinetics leads to rapid CO 2 absorption in the emulsion phase . The absorption of CO 2 in the emulsion phase surpasses the replenishment of CO 2 from the bubbles, resulting in the contraction of the emulsion phase, which is the cause of defluidization in the exothermic stage. The combination of nano-silica coating for CaO and SiO 2 fines addition enhances the porosity in the emulsion phase, thereby facilitating the diffusion of CO 2 from the bubbles into the emulsion phase. Thus, the defluidization of CaO particles is eliminated by simultaneously coating with 5 wt% nano-silica and adding 3 wt% SiO 2 fines (50–75 μm). After this improvement in fluidization , the bed temperature difference is only 12 % of that in defluidization. Furthermore, the effective conversion of CaO particles increases by 10 % compared with that in defluidization. These findings are helpful for solving the defluidization of CaO particles in CaO/CaCO 3 energy process.
研究领域:
能源存储
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
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2025
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IF 13.1
Bin Shao,Yongjun Jiang,Su Li,Zhicheng Xie,Zhi-Qiang Wang,Sheng Dai,Honglai Liu,Feng Qian,Jun Hu
High-temperature calcination of carbonate minerals in energy-intensive industrial sectors is one of the greatest contributors to global carbon dioxide (CO2) emissions. The hydrogenation of the most abundant carbonate minerals could potentially mitigate unavoidable CO2 emissions by converting them into value-added products, but progress has been hindered by a limited understanding of this process. Here, we aim to elucidate the underlying mechanism of self-induced direct hydrogenation of carbonates (DHC) to produce metal oxides and syngas at relatively lower temperature without using any catalysts. Various in situ technologies corroboratively illustrate H2 molecules can penetrate into CaCO3 to form multiple CaO/CaCO3 interfaces, resulting in porous CaO. The density functional theory calculations reveal the neighboring O and C sites at the active CaO/CaCO3 interface are responsible for the heterolytic dissociation of H2, leading to the progressively self-induced DHC. An intrinsic microkinetic analysis by tracing the formation rate of the intermediate further verifies its self-induced catalytic characteristics. This subverts the consensus regarding the infeasible self-catalysis of stable ionic crystals. By lowering the temperature to 650 °C, 100% CaCO3 conversion is achieved with a CO selectivity of 91.8% in a packed bed reactor. Inspired by extensive applications of DHC to various carbonates, this innovative idea of treating carbonates as a White Carbon resource may pave a breakthrough pathway toward Carbon Neutrality in the industry.
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Huizhe Wu,Cong Luo,Penghui Yang,Liqi Zhang,Xiaoshan Li,Fan Wu,Ying Zheng
Calcium-loop (CaL) heat storage technology is a potential backup energy option for concentrated solar power plants. During repeated cycles, calcium-based materials face sintering and agglomeration, leading to a rapid decline in heat storage capacity. The most widely studied closed CO 2 Brayton cycle requires calcium-based materials to undergo repeated cycles in a carbon-dioxide-rich atmosphere, but such work has been limited in the past. In this study, we synthesized various millimeter-sized calcium-based heat carrier pellets using a novel forming method and evaluated their heat storage performance. Using a simultaneous thermal analyzer (TGA/DSC), we evaluated the materials' heat storage performance and investigated the effects of different particle-size alumina on the pore structure of calcium-based pellets through X-ray diffraction, field-emission scanning electron microscopy, N 2 physical adsorption, and reaction kinetics. The study found that calcium-based pellets with large-particle-size alumina formed a web-like pore structure during cycling, exhibiting better structural stability. In contrast, those with small-particle-size better maintained their initial pore structure. Alumina-added calcium-based pellets had more abundant pores, with the large-particle-size alumina group having a specific surface area 3.5 times that of pure calcium oxide pellets. Additionally, the accumulative heat storage density of calcium-based pellets with small-particle-size alumina after 20 cycles was about 1.72 times that of pure calcium oxide pellets. It was worth noting that we found that shortening the carbonation time within the scope of this research could slow down the degradation of the exothermic performance of calcium based pellets.
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Yi Fang,Yingjie Li,Jigang Zhang,Youhao Zhang,Zhiwei Chu,Kuihua Han
CaO/CaCO 3 heat storage is considered a promising technology to solve the intermittency of solar energy. Fluidized-bed reactor is commonly used as calciner/carbonator to efficiently achieve heat storage. In the fluidized-bed reactor, the particle cohesion impedes fluidization of CaO/CaCO 3 particles, adversely impacting heat storage. However, the current research rarely focuses on the cohesive behavior of CaO-based particles in fluidization during CaO/CaCO 3 heat storage process. Furthermore, current research on cohesive behavior primarily focuses on experimental studies, lacking an explanation of the underlying mechanisms at the molecular level. In this work, the cohesive behavior of CaO-based particles in CaO/CaCO 3 heat storage process was studied on a fluidized-bed reactor. The particle cohesion is reflected by the tensile yield strength during the transition from static state to fluidization state. The results indicate that the cohesive behavior of CaCO 3 particles gradually is strengthened with increasing temperature. The tensile yield strength of CaCO 3 particles at 800 °C is 1770 Pa, which is 200 % higher than that at 500 °C. Additionally, the carbonation enhances the cohesive behavior of CaO particles. The tensile yield strength of CaO particles after the carbonation is 55 % higher than that of before the carbonation. The enhanced cohesive behavior of CaO particles during the carbonation results in the defluidization. Molecular dynamics simulation shows that the formation of sintering necks at above 650 °C in the carbonation stage results in cohesive behavior of CaO particles. The introduction of 5 % Al 2 O 3 fines (50–75 μm) as lubricant effectively improves the fluidization quality of CaO particles in the carbonation stage, thereby enhancing the exothermic performance of CaO particles. These findings provide valuable insights for the industrial application of CaO/CaCO 3 heat storage in fluidization.
研究领域:
化学工程
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材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2022
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IF 8.129
Ying Yang,Yingjie Li,Chunxiao Zhang,Zirui He,Jianli Zhao
CaO/CaCO 3 thermochemical heat storage has been considered as a competitive technology in concentrated solar power plants. Carbide slag and red mud are solid wastes from the chlor-alkali industry and aluminum industry, respectively. In this work, the red mud/Mn co-doped high alumina cement-stabilized carbide slag was synthesized for CaO/CaCO 3 heat storage. The effects of the addition of high alumina cement and red mud/Mn on the heat storage capacity, cyclic stability, and optical absorption of the modified carbide slag were investigated. The modified carbide slag exhibits excellent heat storage capacity and optical absorption. The Ca 3 Al 2 O 6 and CaMnO 3 inhibit the growth of CaO grains. FeMnO 3 and Ca 2 Fe 2 O 5 possess high optical absorption properties . The additions of Mn and red mud enhance the heat storage rate and basicity of the carbide slag. The effective conversion of the modified carbide slag is 0.62 after 30 cycles, which is 3.1 times as high as that of the untreated carbide slag. The modified carbide slag reaches the optical absorptance of ~58%, which is 6.5 times as high as that of the untreated one. Thus, the red mud/Mn co-doped high alumina cement-stabilized carbide slag is a potential candidate for the CaO/CaCO 3 heat storage system .
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）