Current Articles

2023, Volume 10,  Issue 3

Display Method:
2023, 10(3)
2023, 10(3): 1-1.
Hydrogen Technology
Current Situation, Analysis of Obstacles and Suggestions for Countermeasures for the Development of Hydrogen Refueling Stations in the Yangtze River Delta
HU Mingyue, LIU Ping, DONG Yanan, XU Chuanbo
2023, 10(3): 1-10. doi: 10.16516/j.gedi.issn2095-8676.2023.03.001
  Introduction  In order to promote the achievement of "carbon peak and neutrality" goals in China, deeply promote the revolution of production and consumption, and build a clean, low-carbon, safe and efficient energy system, the development of hydrogen energy industry is of great significance. Accelerating the development of hydrogen refueling stations is the key to realizing the whole chain of hydrogen energy, and is an important guarantee to realize the healthy and rapid development of hydrogen energy industry. Due to the large scale of hydrogen energy consumption of petrochemical and chemical enterprises and the rapid development of hydrogen fuel cell vehicles and other vehicles in the Yangtze River Delta, promoting the development of hydrogen refueling stations and network construction is the top priority for the promotion of hydrogen energy.   Method  The current situation of the approval process and policy environment of hydrogen refueling station construction in the Yangtze River Delta was analyzed through literature research method, case study method, survey research method and economical measurement, and the obstacles that restrict the development of hydrogen refueling station construction in the Yangtze River Delta were identified.   Result  The lack of legal support for the energy attributes of hydrogen, the lack of guidance for construction standards, and the inadequate multi-sectoral collaboration mechanism have restricted the construction of hydrogen refueling stations and hindered the development of the hydrogen energy industry.   Conclusion  It is suggested to improve the laws and regulations related to hydrogen energy, clarify the boundary conditions between "hazardous chemical" and "energy" of hydrogen energy, improve the construction standards and approval process of hydrogen refueling stations, focus on the core technology, increase financial subsidies, accelerate the promotion of fuel cell vehicles, and promote the development of hydrogen energy industry.
Research on Urban Carbon Neutrality and Hydrogen Energy Application Scenarios in Shanghai
HUANG Xuanxu, SHEN Wei, DING Guanghong
2023, 10(3): 11-22. doi: 10.16516/j.gedi.issn2095-8676.2023.03.002
  Introduction  China's "carbon peak and neutrality" strategy has determined the direction for the development of hydrogen energy. This paper takes Shanghai as an example to study the process of urban emission reduction through energy substitution and the prediction of energy consumption structure in regional central cities under the goal of carbon neutrality. Green hydrogen energy and low-carbon energy sources (such as natural gas and electricity) are complementary to each other. Measuring the scale of hydrogen energy is of great significance to urban hydrogen energy planning, and thus forward-looking prediction and top-level design suggestions are put forward for hydrogen energy development.   Method  By establishing a prediction model of urban carbon neutrality, the total urban carbon emissions were simulated and analyzed, and the total carbon emissions by 2060 were predicted based on the current carbon emissions. According to the energy substitution emission reduction formula and the energy consumption model under the carbon emission reduction constraints, the demand for hydrogen energy, electricity, natural gas and other key energy sources was predicted. Through the investigation of hydrogen energy application scenarios and supply sources, the demand structure and supply composition of urban hydrogen energy were analyzed.   Result  The study shows that Shanghai is expected to peak its carbon dioxide emissions by 2028, with direct emissions peaking at 209 million tons, and then enter the process of total emission reduction. The emission reduction will peak by 2040, and carbon neutrality will be achieved by 2060. Green hydrogen energy, as a zero-carbon energy, will gradually enter the energy consumption structure by 2030. In 2040, the total demand for hydrogen energy will be about 3 million tons, accounting for about 11% of the total energy consumption. By 2060, the total demand for hydrogen energy will be about 8.35 million tons, reaching 21% of the total energy consumption.   Conclusion  Therefore, a reasonable hydrogen energy supply and consumption structure can be built, a hydrogen energy expressway can be constructed, and a regional hydrogen energy center with perfect safety structure, financial structure, production structure and knowledge structure and mastering the pricing power of hydrogen energy can be established through the top-level design of hydrogen energy strategy.
Research on Energy System Planning of Data Center Based on Hydrogen-Electric Coupling
KE Yiming, TANG Hongyu, LIU Wei
2023, 10(3): 23-31. doi: 10.16516/j.gedi.issn2095-8676.2023.03.003
  Introduction  Scientific planning of data center energy system can save energy and reduce carbon, and then orderly realize "dual control" for the total energy consumption and energy intensity as well as "carbon peak and neutrality" goals. However, the existing researches on planning mainly focus on pure electrochemical energy storage, without considering the new storage mode of hydrogen and electricity coupling; few studies establish planning models by integrating sources and loads under the guidance of pure green development.   Method  Based on the concept of green energy supply and hydrogen-electric coupling, the storage, conversion and balance of electricity, heat and cold energy streams were analyzed. Further, from the dimensions of reducing costs and reducing external energy dependence, the optimal configuration model of the data center energy system that takes into account photovoltaic power generation, hydrogen energy storage and electrochemical energy storage was constructed, and was verified by case study.   Result  The case analysis shows that compared with the pure electrochemical energy storage, the planning scheme considering the hydrogen-electric coupling storage has lower costs and lower dependence on external energy, and the proposed model can well reflect the reality.   Conclusion  The research results of this article not only provide quantitative guidance for energy system planning of data centers, but also help data centers achieve energy conservation and carbon reduction, ensuring their green and sustainable development.
Analysis of Coupling Effect Between Green Hydrogen Trading Market and Electricity Market Under Carbon Trading Policy
WANG Haoran, FENG Tiantian, CUI Mingli, ZHONG Cheng
2023, 10(3): 32-46. doi: 10.16516/j.gedi.issn2095-8676.2023.03.004
  Introduction  To achieve the "carbon peak and neutrality" goals, the ways for enterprise energy conservation and emission reduction need to fully explored, and the green and low-carbon policy tools should be fully exploited. Green hydrogen, as a clean energy, has become the key to social low-carbon transition thanks to its full link zero carbon emission. Carbon emission rights trading market is a key policy tool to control and reduce carbon emissions by making use of the market-oriented mechanism. Building a carbon trading center hydrogen energy industry trading mechanism to achieve the coupling of carbon trading and hydrogen energy will greatly promote the achieving of the "carbon peak and neutrality" goals.   Method  Based on this, a coupling mechanism of "green hydrogen market - national carbon trading market - electricity market" was built in this paper. The "green hydrogen market - national carbon trading market - electricity market" was modeled and simulated by further utilizing the system dynamics method, and the interaction of multiple markets was studied.   Result  The results show that: Firstly, the coupling among the green hydrogen market, carbon trading market and electricity market can be realized through green hydrogen certification and carbon quota trading, and it is found that the coupling model is feasible through simulation. Secondly, it is found through the simulation of the basic scenario that the coupling of multiple markets can stimulate the increase of carbon price and control the increase of thermal power generation and green hydrogen production. Finally, increasing the proportion of green hydrogen certification and improving the obsolete unit elimination mechanism and carbon quota auction mechanism will help form a carbon pricing mechanism.   Conclusion  On the one hand, this study diversifies the green hydrogen trading models, promotes the participation of green hydrogen in carbon trading to obtain certain benefits, and reduces the hydrogen energy cost. On the other hand, it makes use of the multi-market linkage mechanism to bring into play the forced effect of carbon price and promote the reduction of the proportion of traditional fossil hydrogen production and thermal power generation.
Development Prospects and Application Scenarios of Green Ammonia Energy Industry Under the Background of Carbon Peak and Neutrality
LUO Zhibin, SUN Xiao, GAO Xiaotian, LIN Haizhou, ZHU Guangtao
2023, 10(3): 47-54. doi: 10.16516/j.gedi.issn2095-8676.2023.03.005
  Introduction  As a zero-carbon fuel, ammonia is easy to achieve safe and low-cost transportation and thus is considered to be an ideal energy source with the same development potential as hydrogen energy. Understanding the development status of core technologies in each link of the ammonia energy industry chain will help grasp the development prospects and direction of the ammonia energy industry.   Method  By investigating the core technologies and application scenarios involved in key links (including preparation, storage, transportation, and utilization) of the ammonia energy industry chain and analyzing the problems faced by the industry development, this study put forward corresponding development suggestions.   Result  Although the traditional Haber process for ammonia synthesis is very mature, the green transition of ammonia production can be achieved via green hydrogen feedstock substitution or adoption of new ammonia synthesis technologies such as photocatalysis, electrocatalysis, bioenzyme catalysis, and plasma drive. The storage and transportation of green ammonia can rely on the traditional synthetic ammonia infrastructure as well as supply chain, and the construction of supporting facilities such as ammonia fuel filling stations should be also strengthened. Ammonia combustion, ammonia fuel cells, ammonia energy storage and other ammonia energy utilization technologies need to be continously researched and developed as well as explored for application demonstration.   Conclusion  The development of green ammonia energy industry is in line with the requirements of building a clean, low-carbon, safe and efficient green energy system in China, and it has a positive impact on our country's energy security. However, the industrialization promotion of ammonia energy still faces many challenges and requires reasonable planning as well as layout and support from policy, finance, innovation platforms and standard system.
Technical Analysis of Ammonia Reforming Hydrogen Production Based on Porous Medium Burner
WANG Zixing, YANG Meie, WANG Haopeng, SONG Minhang
2023, 10(3): 55-62. doi: 10.16516/j.gedi.issn2095-8676.2023.03.006
  Introduction  Hydrogen energy is characterized by the advantages of wide sources, high calorific value, storability, no pollution, and zero carbon emissions. It has become a zero-carbon clean energy with great development potential. At present, mature hydrogen production technologies are mostly based on large-scale hydrogen production, which can hardly meet the demand for compact portable hydrogen production equipment in some important occasions.   Method   In order to meet this demand, this paper first analyzed and summarized the characteristics, advantages and disadvantages, and development trends of the existing large-scale hydrogen production technologies. Besides, considering that ammonia has the advantages of easy liquefaction and storage and high hydrogen content and is an excellent carrier for hydrogen, this paper further proposed the technical idea of using porous medium burner with adiabatic flame temperature to produce hydrogen by ammonia reformation and carried out a systematic analysis from the aspects of technical feasibility, research methods and research contents.   Result  Based on the existing research results of porous medium burners, the feasibility of using porous medium burner for ammonia reforming to produce hydrogen is analyzed. On this basis, the research methods, research contents and technical routes of ammonia reforming for hydrogen production by using porous medium burner are summarized and prospected.   Conclusion  Obtaining the optimal design for the overall structure, microchannel, and reaction carrier structure of the porous medium burner and developing non-precious metal catalyst materials with good performance and low cost will be the main research directions of the porous medium burner for hydrogen production by ammonia reforming. The research in this paper can provide some theoretical and technical support for the development of the technology of hydrogen production by ammonia reforming with porous medium burner.
Comparison and Application Prospects of Ammonia and Methanol Technologies Supporting Large-Scale Development of Green Hydrogen Energy
ZHENG Kexin, GAO Xiaotian, FAN Yongchun, LUO Zhibin, LI Zhen, ZHENG Yun, LIU Yun
2023, 10(3): 63-73. doi: 10.16516/j.gedi.issn2095-8676.2023.03.007
  Introduction  Difficulties in storage and transportation impose restrictions on the large-scale development and utilization of hydrogen energy, so it is necessary to find a solution for large-scale hydrogen storage and long-distance transportation at a low cost.   Method  Ammonia and methanol were widely used in the industry, and both of them could be produced from hydrogen and could be decomposed into hydrogen by cracking reactions. Thus, they could be used as the storage and transportation media for hydrogen energy in the form of chemicals.   Result  The production and utilization technologies of ammonia and methanol are relatively mature, and both green ammonia and green methanol can be produced from green hydrogen. However, as there are few related engineering projects settled in China, it is necessary to promote the further development of technology and the demonstration of engineering projects.   Conclusion  With the progress of "carbon peak and neutrality" developing in depth, hydrogen, as a technology with dual properties of industrial raw material and fuel, will play an important part in promoting energy-saving and carbon reduction. Ammonia and methanol, as mature technologies with complete industry chains and clear advantages for storage and transportation, are expected to become important pathways for hydrogen storage and transportation. Therefore, the development of ammonia and methanol technologies based on green hydrogen is expected to promote the development of the hydrogen energy industry and help China achieve the "carbon peak and neutrality" goals.
Comprehensive Benefit Evaluation of Power to Gas Conversion Considering Green Hydrogen Production and Carbon Capture
SHI Mengshu, SONG Zhicheng, HUANG Yuansheng
2023, 10(3): 74-88. doi: 10.16516/j.gedi.issn2095-8676.2023.03.008
  Introduction  At present, multi-energy complementation is one of the important means to reduce the phenomenon of renewable energy curtailment. With the advancement of power to gas (P2G) technology, the conversion of power and gas has also become an effective way to ensure the supply of comprehensive energy systems. However, in the current P2G link, the power-to-hydrogen (P2H) technology is not economical due to cost constraints, and sustainable development can only be achieved by utilizing resources such as curtailed wind and light. In addition, carbon capture technology also supplies raw materials for the P2G link, thereby reducing the gas purchase cost of the system. Although there have been many studies on P2G technology, few studies evaluate the comprehensive benefits of different links in the whole process of P2G.   Method  This study attempted to construct a microgrid system that is mainly based on renewable energy power generation and supplemented by gas-fired power generation, and conducted detailed calculations for the P2H and hydrogen methanation in the P2G process.   Result  Taking into account the conditions of carbon market, hydrogen market and methane market, a comprehensive evaluation method is applied to compare the economic-environmental-energy efficiency of P2H and power-to-methane (P2M) in different scenarios dominated by power demand, so as to provide reasonable suggestions for promoting the application of P2G in different scenarios.   Conclusion  The results show that when the proportion of renewable energy power generation is very high, the microgrid system with P2H has a higher energy and economic value than that with P2M. Although it is a little less environmentally beneficial, but the difference is not significant. The microgrid system with P2M performs optimally when the proportion of renewable energy power generation to gas turbine power generation reaches the optimal ratio. When the proportion of renewable energy power generation is less than 65%, the benefit of adding P2G is not good.
Analysis and Development Outlook on the Typical Modes of Green Hydrogen Projects
ZHANG Siyu, ZHANG Ning, LU Jing, SHI Qing, DAI Hongcai
2023, 10(3): 89-96. doi: 10.16516/j.gedi.issn2095-8676.2023.03.009
  Introduction  The increasingly high proportion of renewable power sources raises higher requirements for the safe and stable operation of the power system and the reliable supply of electricity. Hydrogen and electricity are complementary in many scenarios of energy consumption. Green hydrogen produced by renewable power will become an important component of the new energy system, which can also facilitate the construction of the new power system. Recently, green hydrogen demonstration projects in China and abroad are burgeoning. However, the typical modes and future development trends are not clear. This paper aims at clarifying the typical modes for green hydrogen projects and providing solutions to issues faced by the large-scale application and the full play of power-hydrogen coupling.   Method  In this paper, the existing green hydrogen demonstration projects in China and abroad were systematically analyzed. The characteristics of the three groups were studied, based on which, the development trends of green hydrogen demonstration projects were proposed. Then, the key problems and challenges were analyzed, and key measures were proposed.   Result  Through the study, the green hydrogen projects are grouped into three categories, which are power-hydrogen coupling projects on the distribution/micro-grid side, large-scale hydrogen production near renewable basis and utilization projects and hydrogen-based flexible adjustment projects. Key issues lying ahead include the lack of coordinated planning between the power and hydrogen system, the less economic competitiveness of green hydrogen and some of the key technologies, equipment and materials are dependent on imports.   Conclusion  To solve these issues and promote the development of green hydrogen projects, the coordinated planning of power and hydrogen system should be strengthened, formulated a set of supporting policies, improved the relevant market mechanisms, accelerated the standards and deployed some essential projects.
Hydrogen Energy Development Strategy of America and Europe and Its Enlightenment to China
ZHAO Zhenli, WANG Gang
2023, 10(3): 97-103. doi: 10.16516/j.gedi.issn2095-8676.2023.03.010
  Introduction  Hydrogen energy plays an important role in the construction of a new energy system due to its extensive sources, convenient storage and transportation, and efficient utilization. This paper systematically analyzes the development strategies of the hydrogen energy industry in the United States and European Union, and combines with the actual development of Chinese industry, and gives specific policy suggestions for the development of the hydrogen energy industry.   Method  The successful experience of hydrogen industry development in the United States and Europe was summarized by combing and analyzing the relevant policies, strategic planning and typical practices of hydrogen energy development in the two major economies.   Result  Based on the current development status of the hydrogen energy industry in our country, this paper puts forward a number of targeted policy recommendations, including strengthening the top-level design to further improve the hydrogen energy industry development policy system; strengthening the guidance of scientific and technological innovation, and attaching importance to the innovation and breakthrough of core technologies in key links of hydrogen energy; expanding the diversified application of hydrogen energy and building a collaborative ecology; attaching importance to international cooperation and taking an active part in the formulation of international rules and standards.   Conclusion  The policy recommendations mentioned in the article can provide reference for relevant departments and industries, so as to further improve the development quality and speed of the hydrogen energy industry.
Modelling and Simulation of Photovoltaic Coupling Water Electrolysis Hydrogen Production System
ZHOU Hang, LI Shaohua, WANG Hui, XU Chunli, TANG Xiaoshu, ZHOU Jun
2023, 10(3): 104-111. doi: 10.16516/j.gedi.issn2095-8676.2023.03.011
  Introduction  This study proposes a photovoltaic coupling electrolysis water hydrogen production system modelling method with the purpose of solving the problem of inconsistency and mismatching of the simulation signals between electrolyser and others modules. The electrolyser is the key equipment in the photovoltaic-coupled water electrolysis hydrogen production system. The common simulation model of the electrolyser is mostly based on the electrochemical theory and established by using the signal model, which could cause signal transmission mismatching and increase system complexity.   Method  In order to solve the problems, it was proposing a method of simulating the electrical characteristics of the electrolytic cell by using the equivalent resistance. By fitting the working characteristic curve of the known electrolyser, the relationship between the working current and the impedance of the electrolyser was obtained. The information of the equivalent resistance of the electrolyser was inherited from the fitting curve and connected to the system as a load. When the system power supply fluctuated, the electrolyser simulation module could adjust the load according to the system working conditions, to achieve linkage with the system power supply.   Result  The simulation results show that the built photovoltaic-coupled water electrolysis hydrogen production system can accurately predict the hydrogen production according to the input light condition and enable load adjustment with the fluctuation of photovoltaic power supply, additionally have a residual value of the fitting result of ≤±0.2.   Conclusion  This method simplifies the photovoltaic coupling electrolysis water hydrogen production simulation system, unifies the simulation signal, and forms system blocks to facilitate system expansion. The simulation output results are in line with the actual operation of the electrolyser and have achieved the expected goal, which proves the feasibility of the simulation method.
Research on Typical Design of Wind-Solar Coupled Hydrogen Production System
SUN Xiang, LIU Chengliang, NIU Xia, ZHAO Luyao
2023, 10(3): 112-119. doi: 10.16516/j.gedi.issn2095-8676.2023.03.012
  Introduction  As wind-solar hydrogen production projects expand in scale and number, there is a growing demand for the design, equipment selection, and economic comparison of green hydrogen production systems. This paper, based on the design experience of multiple similar projects, extracts the typical design of wind-solar coupled hydrogen production system and provides the design selection.   Method  This paper introduced design scheme of wind-solar coupled hydrogen production from the aspects of wind-solar hydrogen storage capacity configuration scheme, electrolysis hydrogen production equipment performance and rectifier comparison, hydrogen and oxygen separation and purification system design, and green hydrogen market and economy analysis.   Result  Capacity configuration can be optimized according to the developed design software through constraint conditions. alkaline electrolysis equipment is the preferred choice for hydrogen production, while proton exchange membrane (PEM) electrolysis equipment can be used for small-scale engineering demonstration. Both thyristor and insulated gate bipolar transistor (IGBT) power rectifiers have their own advantages, and IGBT rectification is gradually being applied in engineering practice. For saving investment, separation and purification can be optimized according to the scale of the project. The market for green hydrogen is huge. As fossil fuel prices continue to rise and the costs of wind-solar coupled hydrogen production systems decrease, coupled with its eco-friendly characteristics, green hydrogen has already become economically competitive.   Conclusion  The wind-solar coupled hydrogen production project is still in the initial demonstration stage, which requires equipment technology progress, design scheme optimization and government policy support to promote the development of green hydrogen industry.
Application of Fuzzy Internal Model Control in Temperature Control in Hydrogen Production by Water Electrolysis
CAO Wei, SHI Xiangjian, CAI Dan, LOU Qinghui, LI Bing, ZHAO Yang
2023, 10(3): 120-127. doi: 10.16516/j.gedi.issn2095-8676.2023.03.013
  Introduction  In order to improve the problem of traditional proportion integration differentiation (PID) controllers overly relying on the mathematical model of the controlled object in the temperature control in hydrogen production by water electrolysis, this paper studies the application of fuzzy internal model control in the temperature control in hydrogen production by water electrolysis, and provides the design process of the fuzzy internal model controller.   Method  Firstly, the importance of temperature in the process of hydrogen production by water electrolysis was analyzed, and some temperature control strategies commonly used in hydrogen production by water electrolysis and their advantages and disadvantages were listed. Then, internal model control theory and fuzzy theory were introduced, and a design method for a fuzzy internal model temperature controller, which was used to achieve precise temperature control in hydrogen production by water electrolysis, was proposed based on these two theories. Finally, simulation verification experiments were conducted.   Result  The results show that the fuzzy internal model control method used in this paper has better control quality in response speed, anti-interference, and robustness compared to the PID control method, solving the problem of traditional PID controller algorithms overly relying on the mathematical model of the controlled object.   Conclusion  The control algorithms used in this paper are correct and effective, and can be applied to the temperature control in hydrogen production by water electrolysis.
Feasibility Research of Underwater Application of Fuel Cell
NIU Yongchao, CHENG Yansen, CHENG Haichao, LI Xuehai
2023, 10(3): 128-134. doi: 10.16516/j.gedi.issn2095-8676.2023.03.014
  Introduction  In order to further improve the cruising ability of underwater equipment, the high specific energy electric energy system is the key to the problem. By comparing the impact of different fuel types on the specific energy of the system, the feasibility of underwater application of fuel cells is explored.   Method  By comparing and analyzing the characteristics of proton exchange membrane fuel cells and solid oxide fuel cells in different hydrogen storage and oxygen storage methods according to the index requirements, it is determined that the cathode side could meet the design requirements by using liquid oxygen supply and the anode side could adopt different supply methods, such as liquid hydrogen, organic liquid, methanol reforming, direct methanol and direct propane.   Result  Depending on the characteristics of different fuel cells, the relevant parameters of the tail gas treatment device are calculated and the feasible schemes of underwater fuel cell energy systems are comprehensively compared. The solid oxide fuel cell energy system with liquid oxygen and liquefied propane or organic liquid, the proton exchange membrane fuel cell with liquid oxygen and organic liquid could meet the design requirements.   Conclusion  The fuel cell energy system can significantly improve the specific energy of the energy system, and the fuel supply form is the main factor affecting the specific energy of the electric energy system.
Design of Gas Turbine Pressure Regulation Station Under the Condition of Mixed Hydrogen Gas
ZHU Junhui
2023, 10(3): 135-142. doi: 10.16516/j.gedi.issn2095-8676.2023.03.015
  Introduction  With the development of "carbon peak and neutrality" goals, the application of photovoltaic and wind power for hydrogen gas production is becoming a hot and front direction. In the hydrogen gas industry, the gas turbine fired with mixed hydrogen gas is the final step to transfer hydrogen into electric power. The pressure regulation station, located between the pipeline network and gas turbine front module, is mainly to regulate the gas turbine fuel at the required temperature and pressure. With the use of mixed hydrogen gas as fuel for gas turbine, it is necessary to study the system configuration of pressure regulation station under new condition, which will provide a practicable solution for the future gas turbine fired with mixed hydrogen gas.   Method  The fuel quantity is given for the F class gas turbine fired with mixture of natural gas and hydrogen gas after the simulation calculation with GT Pro software. The recommended position of mixture tank is also given after consideration of the requirements on the temperature and pressure of F class gas turbine front module. And the material selection of pipe and diameter is presented and the relative items to be focused for the selection of valves is also presented.   Result  The recommended position of mixture tank is given under the condition of gas turbine fired with mixed hydrogen gas. And the material selection of pipe and diameter is presented and the relative items to be focused for the selection of valves is also presented.   Conclusion  For the gas turbine fire with mixed hydrogen gas, special attention shall be paid to the anti-corrosion and anti-explosion due to the big difference of physical properties between the methane (which is the main factor of nature gas) and hydrogen gas. The mixture tank arranged before the control valves of pressure regulation station will be conducive to providing the fuel at the required temperature and pressure for the gas turbine front module. The suitable dimension and material will be selected for the pipe and valves downstream the mixture tank based on the physical properties of mixed gas.
Construction Scheme for the System Coupling Coal Chemical Industry with Green Electricity and Green Hydrogen
SHI Zhipeng, SHI Xiangjian, CAI Dan, FENG Kangkang, LOU Qinghui
2023, 10(3): 143-149. doi: 10.16516/j.gedi.issn2095-8676.2023.03.016
  Introduction  With the advancement of the "carbon peak and neutrality" process, it is imperative to reduce carbon and emissions in the coal chemical industry. The coal chemical process uses a large amount of hydrogen, which mainly converted from fossil fuels, resulting in residual carbon emissions. If green electricity and green hydrogen are coupled with coal chemical construction, it will not only promote energy conservation and emission reduction in the coal chemical industry, but also facilitate the large-scale application of green electricity and green hydrogen.   Method  In this paper, taking the typical coal chemical process of coal to ethylene glycol as an example, the system construction scheme for coupling green electricity and green hydrogen to produce ethylene glycol from coal was elaborated in detail.   Result   Analysis shows that the introduction of green hydrogen has improved the carbon utilization rate of coal to ethylene glycol, from 21.1% in the conventional process to 40.5% in coupled system, while the carbon emission intensity per ton of finished ethylene glycol has decreased from 2.58 t CO2 to 0.93 t CO2. At the same time, integrated construction can reduce the cost of secondary system construction and operation and maintenance.   Conclusion   The coupling construction of green electricity, green hydrogen, and coal chemical industry is technically feasible with large development potential, but there are still many challenges to overcome.
Dynamic Simulation and Energy Comsuption Analysis of 70 MPa Hydrogen Refueling Station
SUN Xiao, CAI Chunrong, LUO Zhibin, WANG Xiaobo, ZHU Guangtao, PEI Aiguo
2023, 10(3): 150-156. doi: 10.16516/j.gedi.issn2095-8676.2023.03.017
  Introduction  Hydrogen refueling station is the key infrastructure for the promotion of hydrogen fuel cell vehicles. 70 MPa hydrogen refueling can significantly improve the endurance and economy of hydrogen fuel cell vehicles. This paper aims to accurately analyze the energy consumption and reduce the operating cost of 70 MPa hydrogen refueling station.   Method  The dynamic thermodynamic model of the hydrogen refueling process was established for the 70 MPa hydrogen refueling station. The law of dynamic pressure and temperature change during single hydrogen refueling process was studied based on the SAE J2601 refueling protocol. The energy consumption composition of single hydrogen refueling, and the energy consumption change of multiple times of hydrogen refueling were analyzed.   Result  The results show that during single hydrogen refueling process, the onboard hydrogen storage cyclinder is refueled in 165 s, the high-pressure hydrogen storage cyclinder is refilled in 295 s, and one hydrogen refueling cycle is completed within 5 min. The energy consumption of hydrogen refueling comes from compressor, intercooler and precooler, among which the energy consumption of the compressor is more than 64%, and the energy consumption of the intercooler is about one third of that of the compressor. The specific energy consumption during single hydrogen refueling process increases from 0.98 kWh/kg to 1.24 kWh/kg as the number of times of hydrogen refueling increases from the first to the twentieth.   Conclusion  The time of single hydrogen refueling process can be shortened by increasing the compressor flow rate. Reducing compressor energy consumption is the key to save energy in hydrogen refueling process. The pressure configuration of the three-stage high-pressure hydrogen storage cyclinder affects many parts of energy consumption. How to allocate the three-stage pressure is worth further study.