Abstract: Based on the process parameters of the industrial natural gas hydrogen plant, a process model of natural gas hydrogen production was established by using Aspen Plus process simulation software. The energy consumption, material consumption, H₂ cost and carbon emission intensity of hydrogen production process under different process parameters were investigated. The results showed that the cracking reaction of methane was the main cause of carbon deposition in the conversion unit, and high water/carbon (H₂O/C) mole ratio was beneficial to inhibit thermodynamic carbon deposition. Besides, low H₂O/C mole ratio, low CH₄ content in dry gas of conversion unit and high H₂ yield of pressure swing adsorption (PSA) unit were beneficial to energy saving and material consumption reduction of H₂ production, and to reduction of carbon emission, the order of their influence on hydrogen production unit from high to low was H₂O/C mole ratio > H₂ yield of PSA unit > CH₄ content in dry gas of conversion unit. The change of CO content in dry gas of medium-temperature WGS had no obvious influence on the energy consumption, material consumption, H₂ cost, and CO₂ emissions intensity of the hydrogen plant.

Key words: hydrogen, natural gas steam reforming, energy consumption, material consumption, cost, CO₂ emissions