METHOD FOR FROSTING CARBON DIOXIDE CONTAINED IN LIQUID METHANE

Method for extracting carbon dioxide contained in liquid methane, comprising: a step of expanding a liquid methane whose carbon dioxide content is greater than 280 parts per million by volume, the expansion being carried out from a pressure higher than 6 bars down to a pressure of 1 bar, the temperature of the liquid methane thus expanded being approximately -161.5°C, a step of transitioning from the gas phase of methane and the solid phase of carbon dioxide in a first, liquid-solid-gas separator (20), with extraction of the solid carbon dioxide by filtering, and separation of the methane gas, to obtain a first, partially decarbonated, liquid methane phase, a step of transferring this first liquid methane phase to a second, solid-liquid separator, the first liquid methane phase being at a temperature of -161°C, the second separator being an exchanger whose temperature is lower than -170°C, carbon dioxide being deposited in the second exchanger, to form a second liquid methane phase, the concentration of carbon dioxide in this second liquid methane phase at -170°C being less than 200 ppmv.