Methanol reformation hydrogen production technology

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Methanol reformation for hydrogen production – This technology has been put into commercial use. I. Introduction to hydrogen energy: According to HC360’s chemical industry reports, hydrogen is a secondary form of energy; it is produced by using other forms of energy through specific processes, unlike coal, oil, and natural gas, which can be extracted directly from the ground and rely almost entirely on fossil fuels. As the consumption of petrochemical fuels increases and their reserves decline, these resources will eventually run out. This makes it urgent to find new, abundant energy sources that do not rely on fossil fuels. Hydrogen is precisely such a new secondary energy source that people are looking forward to, emerging alongside the crisis in conventional energy sources and the development of new secondary energy sources. Hydrogen is at the beginning of the periodic table; it has an atomic number of 1. It is in a gaseous state at normal temperature and pressure, and in a liquid state under extremely low temperatures and high pressures. As an ideal new fusion energy source, it has the following characteristics: 1. It is the lightest element. Under standard conditions, its density is 0.8999 g/l; it can become a liquid at –252.7°C. If the pressure is increased to several hundred atmospheres, liquid hydrogen can turn into metallic hydrogen. 2. It is the gas with the best thermal conductivity, having a thermal conductivity 10 times higher than that of most gases. 3. The most common elements exist in nature. It is estimated to account for 75% of the universe’s mass. Apart from hydrogen in the air, it is primarily stored in water in the form of compounds, and water is the most abundant substance on Earth. It is estimated that if all the hydrogen in seawater were extracted, the total heat generated would be 9,000 times greater than the heat released by all fossil fuels on Earth. 4. Apart from nuclear fuel, hydrogen has the highest calorific value of all fossil fuels, chemical fuels, and biofuels, at 142,351 kJ/kg, which is three times that of gasoline. 5. It has good combustion properties, lights up quickly, has a wide flammable range when mixed with air, and features a high ignition point as well as a fast burning rate. 6. Non-toxic: Compared to other fuels, hydrogen is the cleanest fuel when burned; aside from water and a small amount of hydrogen nitride, it does not produce any environmentally harmful pollutants such as carbon monoxide, carbon dioxide, hydrocarbons, lead compounds, or dust particles. Even the small amount of hydrogen nitride generated can be treated properly so as not to pollute the environment, and the water produced by combustion can be used to produce hydrogen again, allowing for repeated recycling. The product water is non-corrosive and causes no damage to equipment. 7. Various forms of utilization are available. It can generate heat energy through combustion to produce mechanical work in thermal engines, or it can be used as an energy material in fuel cells, or converted into solid hydrogen for use as a structural material. 8. It can exist as a gaseous, liquid, or solid metal hydride, enabling it to meet the various requirements of storage, transportation, and different application environments. 9. Long-distance high-voltage power transmission can be eliminated, and hydrogen can be transported via pipelines over both short and long distances; this improves safety and reduces unnecessary energy losses. 10. Hydrogen eliminates the noise sources associated with internal combustion engines as well as the risks of energy pollution, and it has a high utilization rate. 11. Hydrogen can reduce the weight of fuel, thereby increasing the payload capacity of vehicles; this helps to lower transportation costs. Considering overall benefits over the entire journey, its societal benefits are superior to those of other energy sources. II. The necessity of developing hydrogen energy in our country: The combustion products of oil, coal, and natural gas are carbon dioxide, a greenhouse gas that causes the Earth’s temperature to rise year by year. The latest research conducted by specialized institutions shows that global warming has caused 80% of the ice cap at the summit of Africa’s Kilimanjaro to melt; if this trend is not halted, the ice and snow on the summit will completely disappear within 100 years. Walter, a scientist at the Institute of Botany at the University of Hanover in Germany, pointed out that although global temperatures have risen by only 0.6°C so far, the impact on ecosystems is already posing a serious threat to the survival of animals and plants. Now, the arrival of spring and the growing season for many plants are advancing, and animal food chains could become disrupted in the long term. At the same time, fossil fuels contain impurities, particularly sulfur, nitrogen, phosphorus, arsenic, etc., and their combustion products are acidic, causing air pollution and acid rain. Acid rain not only damages the leaves of crops and vegetables but also reduces their seed germination rates and lowers the protein content in soybeans. Under the effect of acid rain, in the canopies of broadleaf and coniferous forests, ions such as calcium and magnesium accumulate in the rainwater within the canopy, leading to significant loss of nutrient ions from the leaves. This in turn accelerates the absorption and transport of nutrients by the roots, and the nutrients that are reabsorbed are also released in large quantities from the plant ； This cycle leads to nutrient deficiencies, which directly affect forest growth and threaten the material cycle within forest ecosystems; moreover, this process intensifies as the severity of acid rain increases. Acid rain also causes the release of large amounts of aluminum in the soil, as well as the deposition and accumulation of toxic metal elements such as magnesium, which poisons trees. It simultaneously has a direct impact on the soil surface, disrupting the normal biochemical activities of microorganisms, and undermines the decomposition of forest litter and the recycling of nutrients ； Lowering the pH of the AO and A1 layers in the soil suppresses the activity of moderately alkaline fungi, reduces the assimilation and fixation of nitrogen, and leads to a decline in soil fertility. At the same time, acid rain acidifies lakes and washes active aluminum from the soil into rivers and lakes, poisoning fish and altering the entire aquatic ecosystem; this leads to a **decrease in the variety and number of organisms in these water bodies. It also exacerbates the greenhouse effect, irritates the skin, and causes various respiratory diseases such as asthma. China’s energy structure is dominated by coal (accounting for about 75%), and with the rapid development of economic construction, energy consumption is increasing steadily. According to statistics, the national coal consumption was 1.052 billion tons in 1990, rising to 1.28 billion tons in 1995. In 1995, sulfur dioxide emissions from coal burning reached 23.7 million tons, exceeding those of Europe and the United States to rank first in the world. According to the statistics compiled by the **Environmental Protection Agency from monitoring data collected at 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 northern regions of our country experience long, harsh winters, and most areas rely on boilers for heating. Since the energy mix is dominated by coal, smoke and dust pollution has become another environmental issue. **There are certain standard requirements for dust emissions. For example: The indicators for Category II periods in the **GWPB3‑1999 standard** address such situations; therefore, we must find an environmentally friendly clean energy source with large storage capacity, strong sustainability, high thermal efficiency, and various storage forms. Hydrogen energy is precisely such an excellent energy source. With the decreasing availability of fossil fuels, China already lacks an advantage in terms of energy resources, and coupled with a low per capita resource allocation, this necessitates that China place greater emphasis on the development and utilization of alternative energy sources than other countries. Modern transportation vehicles such as cars, airplanes, and ships, which require high mobility, can only rely on \"energy-containing\" sources; therefore, hydrogen energy has undoubtedly become an emerging focus area. III. Analysis of the advantages and disadvantages of developing hydrogen energy in China: China’s research and development in hydrogen energy date back to the early 1960s; Chinese scientists, in order to advance the country’s space program, focused on the production of liquid hydrogen as a fuel for rockets, as well as H2/O2. A great deal of effective work has been done on the research and development 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 the field of hydrogen energy in our country have made considerable progress and achievements in areas such as hydrogen production, storage, and utilization, despite the challenges of limited financial support. The use of hydrogen as an energy source should include 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 been successfully tested in our country, makes use of the nuclear energy released by the thermonuclear reaction of hydrogen; it represents a special application of hydrogen energy. The liquid rockets that use liquid hydrogen as fuel in China’s aerospace sector are typical examples of hydrogen being used as a fuel source. In recent years, Chinese scientists have carried out extensive fundamental research and development 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 mid-size bus that uses a hydrogen-gasoline hybrid fuel. By adding about 4.7 Wt% hydrogen to this fuel, combustion with a hydrogen-gasoline mixture resulted in an average fuel savings rate of 44%. The 30kw hydrogen fuel cell electric vehicle developed independently in our country is scheduled to be completed by the year 2000. Currently, the development and application of PEMFC power systems will become a new driving force for the utilization of hydrogen energy. The main methods for industrial hydrogen production in our country involve using natural gas, petroleum, 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 via water electrolysis and hydrogen production via biomass gasification have now reached 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. skwh/Nm3H2, 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 have been achieved. The Dalian Institute of Chemical Physics, Chinese Academy of Sciences, undertook the development of a \"methanol reformation hydrogen production unit\" for fuel cell electric vehicles as part of the \"Ninth Five-Year Plan\" scientific and technological research project on fuel cell technology; a conceptual prototype was already developed 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,” utilizes a method that requires low energy consumption for hydrogen production – approximately 2.6 kwh/Nm3H2 – thereby bringing hydrogen production technologies with low energy consumption to world-class levels. The Institute of Photochemistry, Chinese Academy of Sciences, undertook the ‘Ninth Five-Year Plan’ scientific and technological research project titled ‘Pilot-scale study on SOX hydrogen production 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 substances. The main source of hydrogen is water, especially seawater; calculations show that 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 endless supply. It is estimated that the theoretical stable reserve of water energy in our country is 700 million KW, while the amount that has been developed is 400 million KW. Once development is completed, a large amount of coal can be saved each year, as well as a significant 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 million cubic meters ； 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 can be seen that China has an extremely rich source of hydrogen, and 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 cheap 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, the advantages of our country 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 amounts 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) ； To obtain hydrogen directly from natural gas, gasoline is required, resulting in approximately 16 grams of carbon dioxide emitted per kilometer (compared to 260 grams per kilometer for ordinary gasoline vehicles), making it highly energy-intensive. Therefore, obtaining large amounts of cheap hydrogen energy will depend on whether it is possible to develop scale-up hydrogen production methods with low energy consumption and low costs. 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. The price of hydrogen to be refueled per 100 kilometers should be as close as possible to that of gasoline; otherwise, this technology will remain forever in the laboratory or prototype stage. Of course, there are other issues related to the use of hydrogen, such as hydrogen refueling stations as part of the infrastructure. Currently, Germany has only one hydrogen refueling station in Munich. Therefore, to promote this technology over the next 10 to 20 years, it is necessary to strengthen infrastructure development by building a network of hydrogen refueling stations. People hope that one day, hydrogen refueling will be as convenient as filling up with gasoline. Furthermore, according to a report in the China Environment News on June 18, hydrogen fuel is considered a clean energy source with excellent development prospects, 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 clean 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, 10–20% 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. When hydrogen fuel is used on a large scale, the hydrogen molecules released during use, combined with those already present in the natural environment, will result in a total amount three times greater than before. Once they reach 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.