The LNG peak-shaving station process flow mainly includes the following steps:
Unloading and storage: After LNG is transported to the station by tank truck, the unloading booster is used to increase the differential pressure between the tank truck pressure and the storage tank to more than 0.2MPa, and then the LNG is transferred from the tank truck to the storage tank through the pressure difference.
Gasification and pressure regulation: When peak-shaving gas supply is required, the LNG in the storage tank enters the cryogenic pump through the discharge pipeline to be pressurized to the process pressure. The pressurized LNG enters the LNG vaporizer to be vaporized into gas, and then reheated to room temperature in the reheater. After being stabilized by the pressure regulating metering skid, it is sent to the city gas pipeline.
BOG recovery and treatment: The BOG (boiling gas) generated during the loading and unloading process first enters the tank meteorological space, then reheats through the BOG vaporizer, pressurizes to the process pressure through the compressor, and finally sends it to the main network to avoid waste.
Safety and metering: City gate stations and storage and distribution stations need to have functions such as filtering, pressure regulation, metering, gas quality detection, safe release, and safe cut-off to ensure the long-term, safety, and stability of gas use.
Functions and roles of LNG peak-shaving stations:
Unloading and storage: LNG peak-shaving stations have unloading and storage functions and can provide sufficient natural gas supply during peak demand.
Gasification and pressure regulation: Through gasification and pressure regulation devices, liquid LNG is converted into gaseous natural gas to meet the needs of urban gas pipelines.
BOG recovery: Effectively recover and process BOG gas generated during loading and unloading to avoid waste and ensure safety.
Safety and metering: Ensure the safe operation and accurate metering of the peak-shaving station to ensure the stability and safety of gas supply.