Medium-Pressure Spherical Tank Technology Demonstrates CIMC’s Strong Capacities in Hydrogen Storage

Hydrogen, as an ideal energy carrier, has an energy density per unit mass of approximately 120 MJ/kg, which is approximately three times that of gasoline, diesel or natural gas. However, in spite of its high energy density, zero-carbon, and renewable nature, hydrogen is inherently flammable and explosive gas, which makes people have to be vigilant at all times.

Ensuring the safe storage and transportation of hydrogen throughout its entire lifecycle in a more effective way is one of the key challenges in hydrogen storage technology today. As a leading company in the spherical tank field in China, Jingmen Hongtu, a subsidiary of CIMC Group, has built hydrogen storage tanks with low-temperature steel, suitable for environments as low as 40 degrees below zero. With these tanks, green hydrogen is compressed in gaseous form and stored in a specially-made and pressure-resistant containers, achieving large-scale storage and safe transport of large-capacity hydrogen in an efficient manner.

As hydrogen technology continues to develop, various forms of hydrogen storage are applicable to different scenarios and demands. Medium-pressure spherical tanks for hydrogen storage offer advantages such as large capacity, low operation and maintenance costs, easy refueling and high efficiency, and therefore they play an important role in the hydrogen industry chain and are widely used in multiple sectors.

To meet the current demands of hydrogen industry, the medium-pressure spherical tanks for hydrogen storage built by Jingmen Hongtu typically operate at storage pressures ranging from 1.5 to 6.4 MPa, with a maximum capacity of 10,000 cubic meters.

In general conditions, the capacity of hydrogen storage tanks is closely related to the pressure: the higher the pressure is, the greater the amount of hydrogen will be stored per unit volume. The key to safely achieve this goal lies in the manufacturing technique of hydrogen storage spherical tanks, which involves several critical links such as stress analysis calculation, material selection, welding processes and structural design.

In the process of manufacturing spherical tanks, Jingmen Hongtu strictly controls main material selection and welding processes test to ensure the comprehensive performance of the spherical tanks, including pressure resistance, erosion resistance and weldability. It simulates severe working conditions such as extreme low temperatures, strong winds and vibrations to evaluate the stress of these spherical tanks under different load combinations through such modeling, ensuring the safety of the spherical tanks throughout the entire lifecycle. In addition, Jingmen Hongtu has also optimized the sealing structure of the hydrogen storage tanks’ process piping to overcome the technical challenge of hydrogen leakage.

As a flammable and explosive gas, when burning, hydrogen flames are invisible and can be difficult to detect. In gas detection scenarios, such situation as failure to obtain the alarm in real time due to misjudging the actual concentration of leaking gas, and missing the chance to timely address potential safety hazards often occurs, and it is even difficult to trace the cause of such incident.

To this end, Jingmen Hongtu, acting as a “super detective”, has broken through the barrier with its technological innovation, and realized the functions of intelligent monitoring, remote control and fault diagnosis for the hydrogen storage tank yards, greatly reducing potential safety risks during operation.

For the purpose of testing the safety and stability of the tanks, Jingmen Hongtu employs high-definition image detectors and infrared flame detectors for dual detection, ensuring timely and accurate fire alarm detection. Meanwhile, it also uses Safety Instrumented System (SIS) to precisely monitor the pressure of the spherical tanks, which realizes interlocking controls for gas inlet and outlet valves, thereby reducing safety risks during long-term operation of spherical tanks.

Once an abnormal change is detected, the infrared flame detection system will automatically activate the fire sprinkler through the interlocking control device, triggering water spray to extinguish fire and cool the spherical tank.

Since 2019, Jingmen Hongtu has been exploring the fields of hydrogen storage and transportation technology and relevant equipment, now possessing a variety of hydrogen storage spherical tank construction technologies and project experience. In June 2023, Jingmen Hongtu undertook the core part of Inner Mongolia Huadian Hydrogen Project — EPC contract for the hydrogen storage system. The project is one of the first large-scale green hydrogen production from renewable energy demonstration projects in China. The six low-temperature steel hydrogen spherical tanks provided by Jingmen Hongtu, each with a capacity of 1,500m³, have been successfully delivered and put into operation, and are expected to produce 7,800 tons of green hydrogen annually, providing a demonstration case that can be replicable and widely applicable for the industry to build a zero carbon, low-cost, safe and reliable green hydrogen supply system.

In the development of the above project, six key technologies involved of Jingmen Hongtu have been granted national patents. What’s more, Jingmen Hongtu has also participated in the preparation of the national standard GB/T12337 for spherical tanks and one hydrogen group standard, contributing to the technological advancement and standardized development of the entire industry.

In recent years, Jingmen Hongtu has focused on key areas and critical links of hydrogen energy. It has undertaken a number of major projects from the national and provincial governments, including the China Energy Engineering Songyuan Hydrogen Energy Industrial Park Project and the Daye Green Power and Green Hydrogen Project. In September 2024, Jingmen Hongtu took an important step toward internationalization by successfully signing its first overseas hydrogen spherical tank project, extending its industrial chain from the domestic market to the international market, and bringing the brand of hydrogen storage spherical tanks manufactured by CIMC to the global stage.