Hydrogen pressure reduction equipment

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This post was last edited by lijie2007521 on 2023-12-6 at 19:42. To adjust the hydrogen pressure in the high-pressure cylinder bank to the level required by the downstream equipment or pipelines, a pressure reducing valve is needed. Since the pressure in the cylinder bank is higher than its outlet pressure, some of the hydrogen gas remains inside the cylinder bank. In this way, the excess pressure can be directly released to the downstream side through an unregulated valve, reducing unnecessary losses (and increasing utilization). Under these conditions, the pressure difference between inlet and outlet is relatively large, while ensuring the gas demand of downstream equipment and pipelines. Therefore, the valve should have a wide adjustment range; when selecting the valve, it is necessary to ensure that the downstream flow remains at an acceptable level under the highest and lowest inlet pressures. In this case, an indirect pressure regulating valve is the most suitable choice, as it features high pressure regulation accuracy, stability, and a large range of pressure adjustment. Hydrogen also exhibits the Joule-Thomson effect; therefore, the gas temperature decreases during regulation, requiring that the components inside the control valve be capable of operating in low-temperature conditions. Currently, the domestic standards are primarily based on GB50177 \"Code for Design of Hydrogen Refueling Stations\", GB50156 \"Technical Standards for Automobile Fuel, Gas, and Hydrogen Refueling Stations\", and GB50516 \"Technical Specifications for Hydrogen Refueling Stations\"; however, these standards do not provide much detail regarding the calculations related to hydrogen filling and unloading. Therefore, it is necessary to refer to relevant foreign standards. Hydrogen depressurization, hydrogen metering, and hydrogen storage are all part of gas storage and transportation. With the strong promotion and demonstration of hydrogen fuel in China, industrialization and scaling up will take place in the future, and the corresponding standards and regulations will also be gradually improved.