Method for liquefying hydrocarbon-rich nitrogen-containing fraction in natural gas, involves temporarily supplying partial flow of boil-off gas fraction of hydrocarbon-rich nitrogen-containing fraction to be liquefied

摘要

The method involves cooling and liquefying hydrocarbon-rich fraction by indirect heat exchange against a coolant or coolant mixture of a coolant circuit. The liquefied hydrocarbon-rich fraction is temporarily stored. A partial flow of a boil-off gas fraction of a hydrocarbon-rich nitrogen-containing fraction to be liquefied is temporarily supplied, where the boil-off gas fraction is accumulated during storage of the liquefied hydrocarbon-rich fraction. The boil-off gas fraction is mixed before it is supplied into the liquefying process and/or during the liquefying process.