Weliya takes you to learn more about hydrogen production from natural gas
Release Date: 2022-01-08 16:26:54 Visit: 290
Natural gas is a petrochemical fuel resource. At present, the world's proven natural gas reserves are more than 140 trillion m³, and the unproven natural gas reserves are also considerable. The use of natural gas resources to optimize hydrogen production has been highly valued, which can reduce the emission of greenhouse gases such as methane and carbon dioxide, and has dual significance for saving energy and protecting the environment.
The methods for producing hydrogen by using methane as a raw material include: obtaining hydrogen by preparing a mixed gas of H2 and CO; obtaining hydrogen by directly decomposing methane. Traditional methods (SMR, POX, ATR) also generate a large amount of CO while generating hydrogen. In order to obtain pure hydrogen, the CO in the syngas needs to be removed, which is not economical for the whole process. The methane cracking reaction can directly obtain hydrogen, the main product of this reaction is hydrogen, and the main product is carbon.
Types of methane hydrogen production reactors: fixed bed reactor, honeycomb reactor, fluid bed reactor, membrane reactor.
The production of hydrogen from natural gas methane has been industrialized. Internationally influential hydrogen production companies include Air Production in the United States, Tcchnip in France, Lurgi in Germany, and Linde in Germany. Linde) and others. The domestic natural gas hydrogen production companies are mainly Changzhou Lanbo Purification Co., Ltd., and the small and medium-scale hydrogen production process technology, device process, and operation management mode jointly developed by it and Qilu Petrochemical Institute. The overall level has reached the international technical level.
At present, the research on using methane-rich gas as a raw material gas for hydrogen production has just started. Scholars at home and abroad have carried out research on reforming hydrogen production with a mixture of methane and CO2 as the main components. Hydrogen production by steam reforming and hydrogen production by autothermal reforming.
For the CO2 dry reforming hydrogen production method, the most studied is the use of catalysts in the reforming process. A suitable catalyst can accelerate the reforming hydrogen production process, improve the gas conversion rate, and reduce the generation of large products. In the methane/CO2 dry reforming process, precious metal catalysts such as nails, iridium, platinum, rhodium can effectively promote the conversion of natural gas, and the generated H2 and CO, only a small amount of CO2 exists in the product; the catalyst has no obvious deactivation symptoms throughout the reforming process. , the amount of carbon deposition on the catalyst surface is also very small.
Ni/La2O3/γAl2O3 catalyst is used as a catalyst for methane/CO2 reforming process. The addition of an appropriate amount of La2O3 can enhance the interaction between Ni and sky-supported Al2O3, increase the reduction temperature of the catalyst, enhance the reducibility of the catalyst, and improve the carbon deposition resistance of the catalyst. properties, thereby improving the activity and stability of the catalyst.
For the hydrogen production process of methane steam reforming, the thermodynamics of reforming hydrogen production were analyzed, and the effects of reaction temperature, molar ratio of methane and oxygen, and the amount of steam added on the reforming performance were studied. It was found that the conversion rate of methane increased with the molar ratio of methane and oxygen, the amount of steam added, and the reaction temperature. When there is NiO/MgO solid solution catalyst in the system, it will have better catalytic reforming performance.
The process of hydrogen production by autothermal reforming of methane is based on the principle that the exothermic process of catalytic oxidation of methane and the endothermic process of methane steam reforming can be coupled to realize self-heating of the whole process. The whole process is carried out at high temperature, and the temperature of the combustion zone is much higher than that of the catalytic zone. The carbon deposition problem in the combustion zone will destroy the entire reaction balance and affect the heat transfer process. In order to solve the problems existing in the process of reforming hydrogen production, people have carried out research on the reforming process. For example, the reforming process is combined with cryogenic separation technology to remove water vapor and CO2 in stages, and finally the high-purity H2 is removed from the separated from the mixed gas.
The methods for producing hydrogen by using methane as a raw material include: obtaining hydrogen by preparing a mixed gas of H2 and CO; obtaining hydrogen by directly decomposing methane. Traditional methods (SMR, POX, ATR) also generate a large amount of CO while generating hydrogen. In order to obtain pure hydrogen, the CO in the syngas needs to be removed, which is not economical for the whole process. The methane cracking reaction can directly obtain hydrogen, the main product of this reaction is hydrogen, and the main product is carbon.
Types of methane hydrogen production reactors: fixed bed reactor, honeycomb reactor, fluid bed reactor, membrane reactor.
The production of hydrogen from natural gas methane has been industrialized. Internationally influential hydrogen production companies include Air Production in the United States, Tcchnip in France, Lurgi in Germany, and Linde in Germany. Linde) and others. The domestic natural gas hydrogen production companies are mainly Changzhou Lanbo Purification Co., Ltd., and the small and medium-scale hydrogen production process technology, device process, and operation management mode jointly developed by it and Qilu Petrochemical Institute. The overall level has reached the international technical level.
At present, the research on using methane-rich gas as a raw material gas for hydrogen production has just started. Scholars at home and abroad have carried out research on reforming hydrogen production with a mixture of methane and CO2 as the main components. Hydrogen production by steam reforming and hydrogen production by autothermal reforming.
For the CO2 dry reforming hydrogen production method, the most studied is the use of catalysts in the reforming process. A suitable catalyst can accelerate the reforming hydrogen production process, improve the gas conversion rate, and reduce the generation of large products. In the methane/CO2 dry reforming process, precious metal catalysts such as nails, iridium, platinum, rhodium can effectively promote the conversion of natural gas, and the generated H2 and CO, only a small amount of CO2 exists in the product; the catalyst has no obvious deactivation symptoms throughout the reforming process. , the amount of carbon deposition on the catalyst surface is also very small.
Ni/La2O3/γAl2O3 catalyst is used as a catalyst for methane/CO2 reforming process. The addition of an appropriate amount of La2O3 can enhance the interaction between Ni and sky-supported Al2O3, increase the reduction temperature of the catalyst, enhance the reducibility of the catalyst, and improve the carbon deposition resistance of the catalyst. properties, thereby improving the activity and stability of the catalyst.
For the hydrogen production process of methane steam reforming, the thermodynamics of reforming hydrogen production were analyzed, and the effects of reaction temperature, molar ratio of methane and oxygen, and the amount of steam added on the reforming performance were studied. It was found that the conversion rate of methane increased with the molar ratio of methane and oxygen, the amount of steam added, and the reaction temperature. When there is NiO/MgO solid solution catalyst in the system, it will have better catalytic reforming performance.
The process of hydrogen production by autothermal reforming of methane is based on the principle that the exothermic process of catalytic oxidation of methane and the endothermic process of methane steam reforming can be coupled to realize self-heating of the whole process. The whole process is carried out at high temperature, and the temperature of the combustion zone is much higher than that of the catalytic zone. The carbon deposition problem in the combustion zone will destroy the entire reaction balance and affect the heat transfer process. In order to solve the problems existing in the process of reforming hydrogen production, people have carried out research on the reforming process. For example, the reforming process is combined with cryogenic separation technology to remove water vapor and CO2 in stages, and finally the high-purity H2 is removed from the separated from the mixed gas.
