| 摘要 |
The air is distilled in an air distillation device (8) to produce a liquid oxygen flow containing the krypton and xenon in the air. This flow is then vaporized. At least part of the gaseous oxygen is used to partially oxidize a hydrocarbon, producing a synthesis gas with at most 0.1 ppm mol. oxygen. Constituents other than krypton and xenon are eliminated from the synthesis gas The partial oxidation is achieved by reacting the oxygen with an excess of hydrocarbon(s) and possibly water vapor, in particular reacting the oxygen with natural gas, methane, naphtha or carbon. The final stage involves a desiccation decarbonation followed by cryogenic separation with a series of steps producing a flow rich in krypton/xenon and also containing methane and carbon monoxide, a hydrogen flow, a carbon monoxide flow and a residual flow. These steps send carbon monoxide to the head of a first column, expansion of the base liquid from this column, elimination of hydrogen in a second column fed at the head by the expanded base liquid, an expansion of the base liquid from the second column and introduction of this liquid into a low pressure column fed with liquid carbon monoxide at the head and producing carbon monoxide at the head and the flow rich in krypton/xenon at the base. In addition, possibly after intermediate reheating of the flow rich in krypton/xenon, there is also a cryogenic separation of the krypton and xenon from the other constituents of this flow. An Independent claim is also included for an installation for carrying out this process with an air distillation device (8) which produces a liquid oxygen flow containing the krypton and xenon from the air, and a vaporizer to vaporize the liquid oxygen. A partial oxidation reactor (2) is fed with the vaporized oxygen flow and a gas containing at least one hydrocarbon to produce a synthesis gas. This synthesis gas is sent through means (3-7) of eliminating constituents other than krypton and xenon from the gas. These means include means (4, 5) of desiccation and decarbonation followed by a cryogenic separation unit (6, 7). The cryogenic separation unit contains a combination of columns designed to produce a flow rich in krypton/xenon and also containing methane and carbon monoxide, a hydrogen flow, a carbon monoxide flow and a residual flow.
|
