Currently, the global hydrogen energy industry is experiencing rapid growth, with China being the world’s largest producer of hydrogen. In 2020, China’s hydrogen demand was approximately 33.42 million metric tons; this figure is projected to rise to 37.15 million metric tons by 2030, accounting for about 5% of final energy consumption. As the goals of carbon peaking and carbon neutrality draw nearer, the importance of hydrogen as a clean energy source is becoming increasingly evident. Aside from hydrogen production via water electrolysis, methods such as coal-based hydrogen production, coke oven gas-based hydrogen production, and hydrogen production via the cracking of natural gas (light oil) and methanol invariably generate large amounts of carbon dioxide tail gas during the hydrogen production process. If directly released into the atmosphere, this not only causes severe environmental pollution but also wastes valuable carbon resources. In response to this situation, our company has specifically developed proprietary new processes and technologies for the recovery and reuse of carbon dioxide tail gas from natural gas and methanol cracking for hydrogen production, thereby realizing a circular economy and turning waste into valuable resources.

Based on the characteristics of carbon-rich tail gas from natural gas and methanol cracking for hydrogen production, as well as the intended uses of the recovered carbon dioxide, we employ different process combinations to recover carbon dioxide from the carbon-rich gas in an environmentally friendly and energy-efficient manner. Depending on the specific hydrogen separation process used, the water and carbon dioxide content in the carbon-rich tail gas will vary.

During the implementation of specific process solutions, we utilize software to perform nonlinear model analysis and optimization of various operational parameters in the CO₂ distillation system using BP artificial neural networks. Simultaneously, guided by the energy-saving principles of distributed energy, we analyze and optimize the refrigeration system and the entire process using a combination of entropy analysis and exergetic analysis. This enables us to tailor a new, green, efficient, and energy-saving CO₂ tail gas recovery process route for our clients. The recovered CO₂ product can be classified into industrial-grade and food-grade (suitable as raw material for dry ice and DMC).