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Study on the Catalytic Performance of Nano-Mesoporous Cobalt-Based Catalysts for Glycerol Dry Reforming

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SSRN 2022年

作者： Dou, Binlin Wang, Yadong Zhang, Hua Wu, Kai Ren, Ruijia Chen, Haisheng Xu, Yujie School of Energy and Power Engineering Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering University of Shanghai for Science and Technology Shanghai200093 China Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing100190 China

Dry reforming is an efficient utilization technology that can convert CO 2 into high-value-added syngas. In this work, nano-mesoporous CeO 2 -supported Co-based catalysts were successfully prepared by the colloidal solution combustion method and used in glycerol dry reforming (GDR) experiments. The characterization results show that the prepared catalyst has a uniform mesoporous structure, and the Co-Fe-Ce catalyst has a higher specific surface area and stronger metal-support interaction than the Co-Ce catalyst. Thermodynamic analysis was conducted using a non-stoichiometric method methodology based on Gibbs free energy minimization. Catalytic experiments were carried out at 650°C to 800°C. The results showed that the Co-Fe-Ce catalyst exhibited higher activity and selectivity in the GDR reaction, and the glycerol conversion of 7CoFeCe at 750 °C reached 84.8%. The 10 h stability experiment shows that the Fe promoter has a positive effect on the stability of the catalyst. The TPO results indicate that Fe doping can suppress filamentous carbon formation. © 2022, The Authors. All rights reserved.

关键词： Catalyst activity

Heavy Oil Upgrading Using Naoh/Cuso4 Composite Catalyst in Aquathermolysis

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SSRN 2022年

作者： Zhou, Yantao Zhao, Qiuyang Miao, Yan Wang, Xuetao Zhang, Yanlong Wang, Yechun Guo, Liejin State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an710049 China Xinjin Weihua Institute of Clean Energy Research Foshan528216 China

To obtain an inexpensive and efficient catalyst in the in-situ upgrading of heavy oil, the NaOH/CuSO4 composite catalyst was proposed in this work. Firstly, the experiments found the viscosity of heavy oil increased with addition of CuSO4 under 300°C in aquathermolysis. Then, the addition of NaOH was found to improve the catalyst capacity of CuSO4 significantly. The NaOH/CuSO4 decreased the viscosity by 81.43% under 300°C. The further analysis revealed the Cu atoms of CuSO4 enter into the heavy oil molecules to increase viscosity, and the NaOH inhabits the viscosity increasing reaction. Besides, the Cu and CuOx with a higher catalytic capacity produced with the addition of NaOH. These conclusions are helpful to understand the aquathermolysis upgrading mechanism and develop a type of inexpensive and efficient composite catalyst. © 2022, The Authors. All rights reserved.

关键词： Sulfur compounds

High-Entropy (Cocrfemnni)3o4 Catalysts for Propane Catalytic Destruction: Effect of the Precipitation Agent

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SSRN 2023年

作者： Ma, Yue Zhang, Yun Jian, Yanfei Jiang, Zeyu Chai, Shouning Li, Lu Xia, Lianghui He, Chi State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China Department of Physics and Information Technology Baoji University of Arts and Sciences Shaanxi Baoji721016 China National Engineering Laboratory for VOCs Pollution Control Material & Technology University of Chinese Academy of Sciences Beijing101408 China

Efficient catalytic destruction of light alkane with ultra-stable and highly symmetric structure is still an intractable issue. High entropy oxides (HEOs) with high chemical disorder and lattice distortion and superior stability have shown great potential in heterogeneous thermocatalysis. Herein, spinel-type HEOs are synthesized via a scalable co-precipitation method with different precipitants (NaOH, Na2CO3, and NaHCO3) and firstly adopted in catalytic destruction of propane. Results demonstrate that the HEO-NaOH possesses the best activity, achieving 90% of propane conversion at 325 °C with an apparent activation energy of 56 kJ·mol-1. Compared with other two HEOs, HEO-NaOH system has larger quantities of surface oxygen vacancies and easily forming several reactive oxygen species (OOH-, O2-, and OH-, etc.), which significantly contribute to the catalytic performance. Moreover, the excellent water resistance of HEOs is verified due to their high conformational entropy and structural stability. Reaction mechanism reveals that OOH- and O2- are the key species in the oxidation of C3H8, which break C-H and C-C bonds in sequence, and are then converted to oxygenated compounds via oxygen oxidation before the final mineralization. The present work provides new insights into the fabrication of efficient catalysts for light alkane destruction as well as other thermocatalytic applications. © 2023, The Authors. All rights reserved.

关键词： Sodium hydroxide

Thermal and hydraulic performance of molten salt steam generation system under varying operating conditions in concentrating solar power plants

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Case Studies in Thermal engineering 2025年 72卷

作者： Jiaming Tian Bo Ren Yiran Duan Biao Li Yueshe Wang State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an 710049 China

To conduct the thermal transport characteristics and operational stability of the steam generation system (SGS) under partial load conditions in concentrating solar power (CSP), a real-scale shell-and-tube steam generator hydrodynamics predictive model is developed. This model integrates lumped parameter methods with the finite volume method to account for heat transfer and phase change. Additionally, in accordance with the prevailing water circulation mode in the CSP plant, a typical model of the natural circulation system is established, while optimal stable operating points of the maximum circulation mass flow rate under varying operating conditions are determined. The results indicate that the inherent stability of the generator strongly lies in the dynamic compromise between its thermodynamic and hydrodynamic characteristics. Under high load conditions, the natural circulation mode demonstrates excellent flow stability. Operating at lower operating pressures results in greater circulation flow and a heightened sensitivity to phase changes. Under system pressures of 13.76, 11.08, 8.39, and 6.71 MPa, the recommended circulation ratios are determined to be 5.38, 7.86, 11.95, and 16.07, respectively. Furthermore, the stability of the circulation curve is optimized by adjusting the structural dimensions of the steam generator. The sensitivity to evaporation capacity and heat exchanger effectiveness is assessed.

关键词： Molten salt storage Steam generator Natural circulation mode Concentrating solar power

Multi-Objective Optimization Design of a Solar-powered Integrated Multi-Generation System Based On Combined Sco 2 Brayton Cycle and Orc Using Machine Learning Approach

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SSRN 2024年

作者： Zhang, Junyi Wang, Jiangfeng Liu, Wenxing Hu, Bin Lou, Juwei Zhao, Pan Institute of Turbomachinery State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China Nuclear Power Institute of China No. 328 Section 1 Changshun Avenue Sichuan Chengdu610213 China DongFang Electric Engineering& Consulting Co. Ltd 18 Xixin Avenue High-tech West Zone Sichuan Chengdu611731 China

With the rapid development of technology and the accelerated degradation of the global environment, there is an urgent need to find a clean and efficient energy solution to replace traditional fossil fuels for energy production. Additionally, this solution should also meet the growing demand for various energy products for energy user. In particular for remote areas such as islands, coastal regions and deserts which are far from the power grid, regular resources such as power, freshwater, and cooling are all scarce. Therefore, integrating freshwater and cooling subsystems into the power generation system to create a multi-generation system can facilitate achieving energy self-sufficiency in remote regions. This paper proposes an integrated multi-generation system powered by a solar power tower (SPT) according to the principle of cascading energy utilization, which includes a supercritical CO2 (SCO2) Brayton cycle, an Organic Rankine cycle (ORC), an ejector refrigeration cycle (ERC), and a reverse osmosis (RO) unit. A mathematical model is established to analyze the system performance from the perspectives of energy, exergy and economics. Different machine learning algorithms including back propagation neural network (BPNN), support vector regression (SVR), random forest (RF) are used to develop prediction models of the system performance. By comparing and analyzing the predictive performance of different machine learning models, the optimal machine learning model is obtained as a surrogate model for the thermodynamic model of the proposed system to accelerate the optimization process. The results show that the BPNN model demonstrates the highest predictive accuracy and the lowest relative error fluctuation, maintaining a relative error of less than 1% for over 97.5% of the data in the testing set. When comparing the multi-objective optimization results of the BPNN model with those of the thermodynamic model from multiple perspectives, it can be observed that the res

关键词： Neural network models

Hydrogen Production from Chemical Looping Steam Reforming of Biomass Waste Cooking Oil

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SSRN 2022年

作者： Zeng, Pingchao Dou, Binlin Zhang, Hua Wang, Yadong Wu, Kai Zhao, Longfei Chen, Haisheng Xu, Yujie School of Energy and Power Engineering Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering University of Shanghai for Science and Technology Shanghai200093 China Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing100190 China

For highly efficient transformation and utilization of waste cooking oil, a new method for hydrogen production by indirect and auto-thermal chemical looping steam reforming (CLSR) of waste cooking oil (WCO) was developed in this work. In conventional and direct CLSR using WCO at a temperature of 650 °C, gas production, hydrogen selectivity, and fuel conversion were low due to the insufficient amount of reducing Ni and heating. Thus, the reactor temperature was increased to 750 °C to pyrolyze enough reducing gas to reduce OCs. Although 84% WCO conversion and 88% hydrogen selectivity were obtained, the OCs deactivated at the last 15 minutes due to the high-temperature sintering of the reduced Ni particles. On this basis, a new type of indirect CLSR with high-temperature steam-assisted pyrolysis of WCO in a two-stages fixed-bed reactor with high stability was developed, which fitted WCO feeding and avoided OCs sintering. The experimental results show that about 90% WCO conversion and about 89% hydrogen selectivity were obtained in indirect CLSR, and the highest hydrogen yield and selectivity were obtained under the conditions of upper pyrolysis temperature of 800 ℃ with a lower CLSR temperature of 600 ℃ and S/C=4.12. In addition, the effect of in-situ CO 2 capture on indirect CLSR achieves the feasibility of hydrogen production and minus carbon emissions. The multiple cycles experiments of indirect CLSR obtained about 90% hydrogen selectivity and fuel conversion, close to 0 CH 4 selectivity, and 24%~26% steam conversion. © 2022, The Authors. All rights reserved.

关键词： Hydrogen production

Curvature-property coupling governed heat transfer deterioration in supercritical helically coiled tubes: Mechanistic insights and mitigation strategies via structural parametrization

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International Journal of Thermal Sciences 2025年 215卷

作者： Chang, Fucheng Xin, Jiaxing Wu, Xiaoyi Li, Liwei Li, Huixiong Zhu, Yanlin National Key Lab of Aerospace Power System and Plasma Technology School of Mechanical Engineering Xi'an Jiaotong University Xi'an710049 China China Special Equipment Testing and Research Institute Beijing100029 China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi'an Jiaotong University Xi'an710049 China Shanghai Nuclear Engineering Research & Design Institute Co. Ltd Shanghai200233 China

The unique thermo-hydrodynamic coupling phenomena in the helically coiled tube (HCT) handling supercritical fluids present both opportunities and challenges for next-generation compact heat exchangers. While the pronounced thermophysical property variations near pseudo-critical temperatures (Tpc) and curvature-induced secondary flows synergistically enhance heat transfer coefficient (HTC), their nonlinear coupling mechanisms may unexpectedly provoke severe heat transfer deterioration (HTD). Through systematic numerical investigations, this study reveals that circumferential wall temperature inhomogeneity (CWTI) exhibits an inverted N-shaped evolution, providing valuable insights for thermal homogenization design near Tpc. The secondary flow Reynolds number (Se), quantifying secondary flow intensity, shows a monotonic increase with decreasing coil diameter (Dc) or inner diameter (Di), reaching saturation in high-enthalpy regions. Notably, CWTI demonstrates non-monotonic behavior, achieving minimum values near Tpc before manifesting distinct rebound characteristics near Tpc conditions. Parametric analysis establishes that: (1) Elevating heat flux (q) increases Se, reducing Dc boosts it by 50.3 %, and decreasing Di raises it by 60.0 %. (2) HTD predominantly initiates at the outer wall under high-q conditions, with Dc reduction achieving HTD suppression and 26.9 % enhancement in the local HTC;(3) Reducing the Di results in a reduction of maximum CWTI by 22.5 %–28.6 %, suggesting that structural parametrization effectively mitigates wall temperature non-uniformity, thus suppressing the HTD. While centered on supercritical water, the dimensionless scaling relationships demonstrate extendibility to other media, with the curvature-property coupling mechanism both elucidating fundamental interactions and guiding robust heat exchanger design. © 2025 Elsevier Masson SAS

关键词： Electric heating

Development in the application of laser-induced breakdown spectroscopy in recent years:A review

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Frontiers of physics 2021年第2期16卷 45-69页

作者： Lian-Bo Guo Deng Zhang Lan-Xiang Sun Shun-Chun Yao Lei Zhang Zhen-Zhen Wang Qian-Qian Wang Hong-Bin Ding Yuan Lu Zong-Yu Hou Zhe Wang Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesSheyang 110016China School of Electric Power South China University of TechnologyGuangzhou 510640China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China Key Laboratory of Photonic Information Technology School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China School of Physics Dalian University of TechnologyNo.2 Linggong RoadGanjingzi DistrictDalian 116024China Optics and Optoelectronics Laboratory Ocean University of ChinaQingdao 266100China State Key Lab of Power Systems Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

Laser-induced breakdown spectroscopy(LIBS)has been widely studied due to its unique advantages such as remote sensing,real-time multi-elemental detection and none-to-little *** the efforts of researchers around the world,LIBS has been developed by leaps and ***,in recent years,more and more Chinese LIBS researchers have put tremendous energy in promoting LIBS *** is worth mentioning that the application of LIBS in a specific field has its special application background and technical difficulties,therefore it may develop in different stages.A review summarizing the current development status of LIBS in various fields would be helpful for the development of LIBS technology as well as its applications especially for Chinese LIBS community since most of the researchers in this field work in *** the present work,we summarized the research status and latest progress of main research groups in coal,metallurgy,and water,*** on the current research status,the challenges and opportunities of LIBS were evaluated,and suggestions were made to further promote LIBS applications.

关键词： laser-induced breakdown spectroscopy application

Improvement and experimental study of scroll expander for organic rankine cycle

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Energy engineering: Journal of the Association of Energy engineering 2020年第4期117卷 225-235页

作者： Li, Lei Tao, Leren Gou, Yanan Zhang, Shan Zaozhuang University Zaozhuang277160 China University of Shanghai for Science and Technology Shanghai200093 China Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering Shanghai200093 China

The scroll expander used in organic Rankine cycle (ORC) system is improved, and its performance is analyzed experimentally. The modified profile and inlet hole of the scroll expander are enhanced, and the performance of the scroll expander before and after the improvement is analyzed. The results show that when the inlet pressure exceeds 0.7 MPa, the waist-shaped hole with a larger area is preferable. The scroll expander with a waist-shaped hole has a larger output power and wider optimal pressure range, and when the inlet pressure is 1.6 MPa, the maximum output power increases by 230 W. The output power and isentropic efficiency of the scroll expander can be improved by modifying the profile. When the inlet pressure is 1.6 MPa and the rotational speed is 1750 r/min, the maximum output power of the scroll expander is 1235 W, which is 120 W higher than that before the improvement. © 2020, Tech Science Press. All rights reserved.

关键词： Rankine cycle