초록 ▼

This invention relates to a VPSA method for the production of a product that is enriched with a more preferred gas from a mixture of the more preferred gas and a less preferred gas and, preferably to a VPSA method for the production of an oxygen-enriched product from air, using an oxygen-preferentia

This invention relates to a VPSA method for the production of a product that is enriched with a more preferred gas from a mixture of the more preferred gas and a less preferred gas and, preferably to a VPSA method for the production of an oxygen-enriched product from air, using an oxygen-preferential adsorbent under equilibrium conditions. In a preferred embodiment the process uses a desorption purge at a nearly constant pressure that is selected to produce a steady stream of oxygen having a purity from 30% to 60% at a pressure in the range of 60 kPa to 20 kPa.

대표청구항 ▼

[ I claim:] [1.] A vacuum/pressure swing adsorption (VPSA) method for extracting a gas mixture enriched in a more preferred gas from a feed gas mixture of said more preferred gas and a less preferred gas, said method employing one or more adsorbent beds each of which comprises an adsorbent which, on

[ I claim:] [1.] A vacuum/pressure swing adsorption (VPSA) method for extracting a gas mixture enriched in a more preferred gas from a feed gas mixture of said more preferred gas and a less preferred gas, said method employing one or more adsorbent beds each of which comprises an adsorbent which, on an equilibrium basis, exhibits a selective adsorption preference for said more preferred gas, said method comprising the steps of:a) passing the feed gas mixture into a feed end of said one or more adsorbent beds at a higher adsorption pressure that is about constant, to allow said one or more adsorbent beds to adsorb the more preferred gas from the feed gas mixture while void gas is allowed to leave from a second end of said one or more adsorbent beds and part of that void gas is fed to a high pressure surge tank for later use during purge and product pressurization steps;b) during a process depressurization step, depressurizing said one or more adsorbent beds by allowing gas to leave at one or both ends of said one or more adsorbent beds with some of the gas leaving said second end of said one or more adsorbent beds being fed to a low pressure surge tank for use as a reflux gas that is poor in said more preferred gas and some of the gas leaving from the feed end of said one or more adsorbent beds being used as product gas that is enriched in said more preferred gas or being recompressed and recycled as a supplement to the feed gas fed to the feed end of said one or more adsorbent beds during later process steps;c) during a process desorption step, flowing said reflux gas that is poor in said more preferred gas from the low pressure surge tank into said another end of said one or more adsorbent beds to purge out some of the adsorbed more preferred gas while more of said product gas that is enriched in said more preferred gas is allowed to leave from the feed end of said one or more adsorbent beds at a lower pressure that is about constant or declining; andd) during a process repressurization step, repressurizing said one or more adsorbent beds by allowing gas to enter at one or both ends of said one or more adsorbent beds, where said reflux gas that is poor in said more preferred gas, is fed from the high pressure surge tank into the second end of said one or more adsorbent beds and where some of said feed gas mixture is fed into the feed end of said one or more adsorbent beds.