As a core facility for refueling liquefied natural gas (LNG) vehicles, an LNG refueling station's equipment configuration must balance safety, efficiency, and environmental friendliness. According to industry standards and actual application scenarios, the main equipment can be divided into four major systems: storage, refueling, safety control, and auxiliary systems. The specific components are as follows:
Storage System: LNG Storage Tanks and Supporting Equipment
LNG storage tanks are the core storage equipment of a refueling station. They typically employ a double-layer vacuum insulation structure. The inner tank is made of low-temperature resistant austenitic stainless steel (such as 304L), and the outer tank is made of carbon steel or stainless steel. The space between the inner and outer tanks is filled with insulating materials such as perlite to reduce heat loss. The tank capacity is designed according to the scale of the refueling station, with common specifications ranging from 30m³ to 200m³. The design pressure is generally 1.0MPa, and the operating temperature is as low as -162℃.
Supporting equipment includes a tank booster (used to vaporize LNG and return it to the top of the tank to maintain stable internal pressure), a tank pressure regulating valve (automatically controls the internal pressure within a safe range), and a level gauge (monitors the tank level in real time to prevent overfilling). In addition, the tank area must be equipped with safety valves, emergency shut-off valves, and explosion-proof walls to deal with emergencies such as overpressure or leakage.
Refueling System: LNG Pumps and Dispensers
The LNG pump is the power source of the refueling system, responsible for transporting cryogenic liquid from the tank to the dispenser. Common types are submersible pumps (operating directly immersed in LNG) or centrifugal pumps, with flow rates typically ranging from 50-20000 Nm³/h and operating pressures from 2-20 MPa. The pump body must be made of cryogenic materials and equipped with variable frequency speed control to adapt to different refueling needs.
The dispenser is the device that directly interacts with the vehicle. Its core functions include flow metering, temperature compensation, and pressure regulation. The metering structure is mostly single-channel metering, using a mass flow meter to accurately calculate the refueling volume, with an error rate controlled within ±0.5%. The refueling machine must have an explosion-proof design and integrate audible and visual alarm functions, immediately triggering an alarm when a gas leak or abnormal pressure is detected. Furthermore, the refueling machine interface must conform to international standards (such as ISO 14469) to ensure compatibility with different vehicle models.
