Current status of hydrogen production technology development in China

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According to statistics from the **Environmental Protection Agency on monitoring data from 2,177 environmental monitoring stations across the country over a period of 3 years (1991–1993), 62.3% of cities had an annual average concentration of sulfur dioxide that exceeded the **second-level standard (0.06 mg/m3), while the daily average concentration exceeded the **third-level standard (0.225 mg/m3). As a result, acid rain with a pH value below 5.6 covered approximately 30% of the country’s territory. Dust explosions and dust pollution were severe, affecting both the ecological environment and economic development. The winters in northern China are long and cold, and most areas rely on boilers for heating. Since the energy source is primarily coal, dust pollution has become another environmental issue. **There are certain standard requirements for dust emissions. In light of these situations, we must find an environmentally friendly clean energy source with large storage capacity, strong sustainability, high thermal efficiency, and various storage forms, and hydrogen energy is precisely such an excellent energy source. China’s research and development in hydrogen energy date back to the early 1960s; Chinese scientists, in order to advance their country’s space program, focused on the production of liquid hydrogen, as well as H2/O2, for use as rocket fuel. A great deal of effective work has been done in the research, development, and advancement of fuel cells. The development of hydrogen as an energy carrier and in new energy systems dates back to the 1970s. Over the years, experts and scientists in China’s hydrogen energy sector have made significant progress and achievements in areas such as hydrogen production, storage, and utilization, despite working under difficult conditions with limited financial support. The use of hydrogen as an energy source should encompass the following three aspects: utilizing the thermal energy released from the reaction between hydrogen and an oxidizer, obtaining electrical energy directly through the electrochemical reaction between hydrogen and an oxidizer in the presence of a catalyst, and utilizing the nuclear energy released from the thermonuclear reaction of hydrogen. The hydrogen bomb, which has already been successfully developed in China, makes use of the nuclear energy released by the thermonuclear reaction of hydrogen; it represents a special application of hydrogen energy. Liquid rockets fueled by liquid hydrogen used in China’s space industry are typical examples of hydrogen being used as a fuel source. In recent years, Chinese scientists have carried out extensive fundamental research and developmental work in this area. Xi’an Jiaotong University has conducted research on “hydrogen combustion and power cycles” as well as studies on the flow fields of hydrogen combustion and evaluations of the performance of hydrogen flames. The Institute of New Materials and the Institute of Internal Combustion Engines at Zhejiang University have successfully modified a medium bus that uses a hydrogen-gasoline mixture as fuel. By adding about 4.7 Wt% hydrogen to this mixture, an average fuel savings rate of 44% was achieved. The 30kw hydrogen fuel cell electric vehicle developed independently in China is scheduled to be completed by the year 2000. Currently, the development of applications for PEMFC power systems will become a new driving force for the utilization of hydrogen energy. The main methods for industrial hydrogen production in China involve using natural gas, oil, and coal as raw materials, reacting them with steam at high temperatures to produce hydrogen; it can also be produced through partial oxidation. These hydrogen production methods are relatively mature in terms of technology, but using fossil fuels and electricity to produce hydrogen is not economical or efficient in terms of resource utilization. Current industrial hydrogen production is primarily aimed at meeting the needs of sectors such as chemicals, petroleum refining, metallurgy, and electronics. Methods such as hydrogen production through water electrolysis and hydrogen production via biomass gasification have now reached commercial scale. Among them, the method of producing hydrogen by electrolyzing water using cheap electricity is the main approach for large-scale hydrogen production at present; however, the electricity consumption is currently too high, at around 4.5 kW·h per Nm3 of H2, and improvements are urgently needed. In addition, the “methanol reformation hydrogen production technology” developed by the Shanxi Coal Chemistry Institute of the Chinese Academy of Sciences has been put into practical use; the current maximum production capacity is 360 Nm3/h, and series and batch production has been achieved. The Dalian Institute of Chemical Physics, Chinese Academy of Sciences, was responsible for the development of a \"methanol reformation hydrogen production unit\" for fuel cell electric vehicles as part of the \"9th Five-Year Plan\" scientific and technological research project on fuel cell technology; a conceptual prototype of this unit was already created months earlier. The “Ninth Five-Year Plan” scientific and technological research project undertaken by the University of Petroleum, titled “Expanded experimental study on the production of hydrogen from H2S,” employs a method that requires low energy consumption for hydrogen production – approximately 2.6 (kW·h) per Nm3 of H2 – thereby bringing hydrogen production technologies with low energy consumption to the world’s advanced level. The Institute of Photochemistry, Chinese Academy of Sciences, undertook the scientific and technological research project during the Ninth Five-Year Plan period titled \"Pilot-scale study on SOX hydrogen production technology from flue gas.\" The institute’s research on artificial photosynthesis for water splitting to produce hydrogen, as well as on the use of unconventional resources for hydrogen production, has reached world-class levels. In the fields of photochemical, biomass, and electrochemical hydrogen production, institutions such as the Lanzhou Institute of Chemical Physics, research centers focused on microorganisms, as well as Nankai University and Tianjin University have also carried out extensive fundamental research. At present, the only way to obtain large quantities of elemental hydrogen is through artificial production from natural gas, oil, coal, biomass energy, and other hydrogen-rich organic materials. The largest source of hydrogen is water, especially seawater; according to calculations, 9 tons of water can produce 1 ton of hydrogen (and 8 tons of oxygen). The heat of combustion of hydrogen is 28,900 kcal/kg, and the combustion product of hydrogen and oxygen is water, thus allowing water to be regenerated. It can be seen that using water as a raw material for hydrogen production enables a sustainable cycle for the generation and utilization of hydrogen, ensuring an inexhaustible supply. It is estimated that China’s theoretical stable potential for water-based energy is 700 million KW, while the actual amount that can be utilized is 400 million KW. Once this resource is developed, it will enable significant savings in coal usage each year, as well as a substantial reduction in sulfur dioxide emissions. Industrial by-product hydrogen is also an effective way to supply fuel to fuel cells. According to statistics, China’s annual hydrogen recovery volume in the synthetic ammonia industry can reach 14,108 m ； In the chlor-alkali industry, 87,106 m of hydrogen is available for recovery. Furthermore, large amounts of hydrogen can be recovered in the production processes of the metallurgical industry, fermentation wineries, and butanol solvent plants. The total amount of hydrogen that can be recovered from these various industrial by-products is estimated to exceed 1.5 billion cubic meters. It is evident that China has an extremely abundant source of hydrogen, and it also possesses a certain foundation in related technologies. Hydrogen production methods such as water electrolysis and biomass gasification are now being implemented on a large scale. Among them, the method of producing hydrogen by electrolyzing water using low-cost electricity will remain the main approach for large-scale hydrogen production in the future. Furthermore, replacing coal and oil with hydrogen does not require major modifications to existing technology and equipment; current internal combustion engines can be used after slight adjustments, which helps reduce the costs associated with using hydrogen energy. From this, China’s advantages in developing hydrogen energy become evident. The development of anything has two sides. While recognizing its advantages, we must also be aware of the difficulties it faces. The production of large quantities of cheap hydrogen is fundamental to realizing the utilization of hydrogen energy. Currently, cheap hydrogen production technologies and safe, reliable methods for storing and transporting hydrogen are the two key issues. Obtaining hydrogen requires a large amount of electrical energy to separate hydrogen from oxygen (approximately 3 kWh of electrical energy is needed to produce 1 liter of liquid hydrogen) ； Extracting hydrogen directly from natural gas requires gasoline, resulting in approximately 16 grams of carbon dioxide emitted per kilometer (compared to 260 grams per kilometer for regular gasoline cars), making it highly energy-intensive. Therefore, obtaining large amounts of cheap hydrogen energy will depend on whether low-energy and low-cost methods for large-scale hydrogen production can be developed. However, in the field of transportation, major automobile-producing countries such as the United States, Germany, France, and Japan have long since introduced hydrogen-fueled demonstration vehicles and conducted hundreds of thousands of kilometers of road testing. Among them, countries such as the United States, Germany, and France use hydrogenated metals to store hydrogen, while Japan uses liquid hydrogen. Tests have shown that cars powered by hydrogen hold great promise in terms of economy, adaptability, and safety, but two major obstacles remain: low hydrogen storage density and high costs. The former limits the distance a vehicle can travel continuously, while the latter is mainly due to the high cost of the liquid hydrogen supply system. “The key to “ecological hydrogen energy” is not technology, but cost. In terms of environmental protection and market demand, cleanliness and cost are two key parameters; having only cleanliness but high costs means there is no market, making it difficult to promote the product. Therefore, to implement this strategy, it is necessary to reduce costs purposefully. According to a report in the China Environment News on June 18, hydrogen fuel has always been regarded as a clean energy source with great development potential, as it produces only water when releasing energy. The United States has planned to allocate billions of dollars in dedicated funds to develop hydrogen energy as a priority alternative energy source. However, a recent paper published in the American journal Science raises objections: the widespread promotion and use of hydrogen fuel would increase damage to the ozone layer, which plays a crucial role in protecting the Earth from ultraviolet radiation. The article points out that if hydrogen energy completely replaces fossil fuels, 10% to 20% of the hydrogen may leak from the pipelines, storage devices, processing equipment, and fuel cells in vehicles or power plants. Hydrogen molecules are light in weight and spread easily into the sky. After extensive use of hydrogen fuel, the hydrogen molecules released during use, together with those already present in the natural environment, will result in a total amount three times greater than before. After reaching the stratosphere, they are oxidized to form water. This will lower the temperature of the stratosphere and disrupt the chemicals in the ozone layer, causing the ozone holes over the Arctic and Antarctic to expand, with the affected area potentially reaching 8%. Therefore, as research on hydrogen energy progresses, we must approach it using a comprehensive evaluation method; we cannot focus solely on technology, but must also take other factors into account.