For the first time in China, a full-scale blowdown test of a 10 MPa high-pressure hydrogen pipeline was successfully conducted, breaking the safety bottleneck of long-distance hydrogen energy transmission.

On December 10, the first full-scale venting test of a 10 MPa high-pressure, DN250mm riser diameter hydrogen pipeline, organized and implemented by the National Pipeline Group, successfully concluded in Inner Mongolia. The success of this test marks a significant technological breakthrough for China in the safe venting of high-pressure hydrogen pipelines, providing key data support and engineering basis for the safe design of new pure hydrogen pipelines and the modification of existing natural gas pipelines for hydrogen transmission, solving the core safety issues of large-scale, long-distance storage and transportation of hydrogen.

Extreme Condition Validation Overcomes World-Class Technical Challenges

As the first full-scale venting validation of hydrogen under high pressure conditions in China, this test directly addressed three major technical challenges in hydrogen venting: the extremely small size of hydrogen molecules that can easily cause "hydrogen embrittlement," a wide flammability limit (4%-75%) with very low ignition energy, and the great difficulty in safety control under full-scale scenarios. The test team adopted a systematic approach of "principle research + numerical modeling analysis + physical testing" to deeply analyze the diffusion and combustion mechanisms during the hydrogen venting process, establishing a comprehensive verification plan covering multiple pressure levels from 1 MPa to 10 MPa, various riser heights, and flame arrester configurations.

Notably, this test used a real DN250mm riser diameter, and its technical achievements can be directly applied to the venting needs of hydrogen pipelines with mainline diameters of DN700mm and above. Through cold venting diffusion monitoring and ignition venting combustion tests, the team comprehensively obtained core data on hydrogen concentration distribution, flame morphology, and thermal radiation intensity, clearly understanding the flow trajectory and safety boundaries of hydrogen venting at different pressures, fundamentally changing the previous passive situation of relying on theoretical calculations or foreign standards.

Triple Core Values Empower Large-Scale Development of the Hydrogen Energy Industry

This technological breakthrough brings multiple substantial benefits to the development of the hydrogen energy industry, highlighting three core values:

1. Strengthening the Foundation of Safe Design: The precise data accumulated from the test provides a scientific basis for the height design of venting risers, selection of flame arrestors, and determination of safety protection distances for new pure hydrogen pipelines, shifting pipeline design from "experience-based estimation" to "data-supported," significantly enhancing the intrinsic safety level of hydrogen transmission pipelines.

2. Revitalizing Existing Pipeline Network Assets: With over ten thousand kilometers of existing oil and gas trunk pipelines in China, the test results can be directly used to assess the adaptability of the venting systems of in-service natural gas pipelines modified for hydrogen transmission, clarifying the standards and scope of modifications, avoiding blind reconstruction, and saving huge investment costs for the "hydrogenization transformation of oil and gas pipeline networks."

3. Building an Autonomous Standards System: Based on the test data, efforts will be accelerated to formulate China's technical standards for hydrogen pipeline venting, filling the domestic gap in related fields, breaking the monopoly of foreign technologies, providing a unified safety benchmark for the industry chain, and promoting the transition of hydrogen storage and transportation from "pilot demonstration" to "large-scale promotion."

Boosting Energy Transition and Strengthening the Foundation of a New-Type Energy System

As a clean energy source with prominent zero-carbon attributes, hydrogen's optimal route for large-scale cross-regional allocation is through long-distance hydrogen pipelines. Safe venting is a core safeguard in the stages of pipeline transportation, storage, and operation and maintenance. A relevant official from the National Pipeline Network Group stated that the results of this test will further improve China's hydrogen storage and transportation technology system, creating conditions for the implementation of major national projects such as the "Hydrogen from West to East." In the future, the company will continue to focus on the field of hydrogen storage and transportation, promote technological innovation and engineering applications, and accelerate the construction of new-type energy infrastructure, providing solid support for the green and low-carbon transition of energy and the realization of the "dual carbon" goals.

Industry experts pointed out that with the breakthrough in safe venting technology for high-pressure hydrogen pipelines, the "storage and transportation bottleneck" in China's hydrogen industry chain has been substantially alleviated, which will accelerate the substitution and application of green hydrogen in industries such as manufacturing and transportation, injecting strong momentum into the construction of a new-type energy system.