Driven by the dual carbon goals, green hydrogen and green methanol, as clean and low-carbon new energy carriers, are becoming the core tracks for the chemical industry’s transformation and upgrading. Valves, as key components that control fluid flow and regulate parameters throughout the production process, have their selection and compatibility directly determining the safe and stable operation of projects.
Understanding the requirements for valves in real production environments helps in selecting the appropriate valves.
Green Hydrogen Scenario: Hydrogen Embrittlement Resistance is the Core Assessment Indicator
Green hydrogen production, from water electrolysis for hydrogen generation, storage and transportation, to purification, must address the high permeability of hydrogen, hydrogen embrittlement, and its flammable and explosive properties. The material and performance requirements for valves in this context are significantly more stringent than in ordinary chemical scenarios.
Currently, the mainstream core valve categories include high-pressure hydrogen ball valves, hydrogen precision control valves, ESD emergency shut-off valves, low-temperature valves for liquid hydrogen, and hydrogen rotary check valves. These cover sizes DN15-DN200 and pressure ratings PN16-PN700 and can adapt to a wide temperature range from -253°C to 200°C, basically covering all scenario requirements from electrolyzer hydrogen production to high-pressure hydrogen storage and liquid hydrogen transportation.
In this scenario, valves are mainly used at critical points such as ultra-pure water supply pipelines for electrolyzers, medium shut-off for hydrogen production devices above 30 MPa, precise green hydrogen pressure and flow control, emergency isolation of high-pressure hydrogen cylinder groups, and reverse flow protection of long-distance hydrogen pipelines. Therefore, cost-saving should not compromise quality.
Three core requirements should be emphasized in valve selection:
- Valve materials must prioritize 316LMo low-sulfur and low-phosphorus austenitic stainless steel. For extremely high-pressure conditions of 70 MPa, nano-crystalline reinforced hydrogen embrittlement-resistant alloys should be used to fundamentally prevent material embrittlement and cracking due to hydrogen atom penetration.
- Sealing structures must meet ISO15848-1 low emission standards, with helium leakage rates ≤1×10⁻⁶ Pa·m³/s, complying with the latest GB/T 42177-2022 “Technical Specification for Valves for Hydrogen Use.”
- Hydrogen-involved valves must pass third-party hydrogen pressure cycling tests and obtain SIL3 functional safety certification and ExdIICT6 explosion-proof certification before being put into use.
Green Methanol Scenario: Multi-Medium Adaptation is Key
Green methanol uses a synthesis process of “green hydrogen capturing CO₂.” From CO₂ purification and methanol synthesis to distillation and storage, valves need to simultaneously adapt to hydrogen, CO₂, and methanol—three highly hazardous media with completely different characteristics—making the adaptability requirements more complex.
The core commonly used valves include methanol solenoid valves, programmable valves, pneumatic control valves, methanol stainless steel safety valves, triple-offset butterfly valves, and V-type control ball valves. These cover PN16-PN160 pressure ratings and can meet the transportation needs of multiple media such as water, gas, and oil.
Typical application scenarios for these valves include flow control in CO₂ compression and purification units, medium shut-off in methanol synthesis towers, support control for methanol distillation tower float valves and trays, safety pressure relief for methanol tank breathing valves, and programmable switching in syngas distillation pipelines. Among them, the pressure vacuum valves in the tank area also need to be certified under IMO MSC.1621, suitable for long-distance ventilation pipelines while simultaneously enabling flame arresting and near-zero emissions.
Key Points for Selection
- Valve bodies should preferably be made of 304/316 stainless steel, offering high-temperature resistance, corrosion resistance, and high-pressure stability.
- The anti-static design must meet an electrical resistance of ≤10⁶ ohms between the body and the closure parts to prevent the risk of static electricity generated by the flow of flammable and explosive media like methanol.
- Overall performance should comply with the EN 12569 chemical and petrochemical valve standard.
Valve selection is not just theoretical; it requires understanding actual usage scenarios and then making targeted choices based on the characteristics of different valves, aiming to maximize usability, safety, and overall valve operational experience.
As a professional valve manufacturer, TEJI Valve Group has obtained API 6D, API 600, API 602, API 607, ISO9001, ISO14001, OHSAS18001, EAC (TR-CU), and TS certifications. TEJI possesses over 500 sets of metal processing, cutting, machining, and inspection equipment to ensure outstanding quality and service. Before delivery, every valve undergoes 100% testing and inspection from raw material to packaging according to standard requirements. We are committed to providing the highest quality products and services to meet the needs of the valve industry.
