Patent ID: 7223607

Claim:
A process for the detection of hydrocarbons other than methane in a liquid oxygen bath of an evaporator of a unit for the production of gases from the air, comprising the steps of: (1) withdrawing a sample of liquid oxygen from the said bath, (2) evaporating said liquid oxygen, thereby producing an evaporated gas comprising at least 95% oxygen, and containing methane and hydrocarbons other than methane, and (3) detecting the level of hydrocarbons other than methane in the said evaporated gas, said detection comprising the following stages: (a) adding hydrogen to said evaporated gas to provide a hydrogen/oxygen ratio between 10% and 40%, (b) measuring the level of combined hydrocarbons in said gas, providing a first value for the combined hydrocarbons, (c) incinerating the hydrocarbons other than methane in said gas, (d) measuring the level of methane in said gas, providing a second value, and (e) calculating the amount of hydrocarbons other than methane by the difference between the first value and the second value.