초록 ▼

Pressure swing adsorption (PSA) separation of a gas mixture is performed in an apparatus with a plurality of adsorbent beds. The invention provides rotary multiport distributor valves to control the timing sequence of the PSA cycle steps between the beds, with flow controls cooperating with the rota

Pressure swing adsorption (PSA) separation of a gas mixture is performed in an apparatus with a plurality of adsorbent beds. The invention provides rotary multiport distributor valves to control the timing sequence of the PSA cycle steps between the beds, with flow controls cooperating with the rotary distributor valves to control the volume rates of gas flows to and from the adsorbent beds in blowdown, purge, equalization and repressurization steps.

대표청구항 ▼

[ We claim:] [1.] Process for separating first and second components of a feed gas mixture, the first component being more readily adsorbed under increase of pressure relative to the second component which is less readily adsorbed under increase of pressure over an adsorbent material, such that a ga

[ We claim:] [1.] Process for separating first and second components of a feed gas mixture, the first component being more readily adsorbed under increase of pressure relative to the second component which is less readily adsorbed under increase of pressure over an adsorbent material, such that a gas mixture of the first and second components contacting the adsorbent material is relatively enriched in the first component at a lower pressure and is relatively enriched in the second component at a higher pressure when the pressure is cycled between the lower and higher pressures at a cyclic frequency of the process defining a cycle period; providing for the process a number "N" of substantially similar adsorbent beds of the adsorbent material, with said adsorbent beds having first and second ends; and further providing for the process a first rotary distributor valve connected in parallel to the first ends of the adsorbent beds and a second rotary distributor valve connected in parallel to the second ends of the adsorbent beds, with flow controls cooperating with the first and second distributor valves; introducing the feed gas mixture at substantially the higher pressure to the first distributor valve; and rotating the first and second distributor valves so as to perform in each adsorbent bed the sequentially repeated steps within the cycle period of:(A) supplying a flow of the feed gas mixture at the higher pressure through the first distributor valve to the first end of the adsorbent bed during a feed time interval, withdrawing gas enriched in the second component from the second end of the adsorbent bed, and delivering a portion of the gas enriched in the second component as a light product gas,(B) withdrawing a flow of gas enriched in the second component as light reflux gas from the second end of the adsorbent bed through the second distributor valve, so as to depressurize the adsorbent bed from the higher pressure toward an equalization pressure less than the higher pressure, while controlling the flow so that the pressure in the bed approaches the equalization pressure within an equalization time interval,(C) withdrawing a flow of light reflux gas enriched in the second component from the second end of the adsorbent bed through the second distributor valve, so as to depressurize the adsorbent bed from approximately the equalization pressure to an intermediate pressure less than the equalization pressure and greater than the lower pressure, while controlling the flow so that the pressure in the bed reaches approximately the intermediate pressure within a cocurrent blowdown time interval,(D) withdrawing a flow of gas enriched in the first component from the first end of the adsorbent bed through the first distributor valve, so as to depressurize the adsorbent bed from approximately the intermediate pressure to approach the lower pressure, while controlling the flow so that the pressure in the bed approaches the lower pressure within a countercurrent blowdown time interval,(E) returning a flow of light reflux gas enriched in the second component from the second distributor valve to the second end of the adsorbent bed at substantially the lower pressure, while withdrawing gas enriched in the first component from the first end of the adsorbent bed and through the first distributor valve over a purge time interval, said flow of gas enriched in the second component from the second distributor valve being withdrawn from another of the adsorbent beds which is undergoing cocurrent blowdown step (C) of the process,(F) returning a flow of light reflux gas enriched in the second component from the second distributor valve to the bed, so as to repressurize the adsorbent bed from approximately the lower pressure to approach the equalization pressure, while controlling the flow so that the pressure in the bed approaches the equalization pressure within an equalization time interval, said flow of gas enriched in the second component from the second distributor valve being withdrawn from another of the adsorbent beds which is undergoing equalization step (B) of the process,(G) admitting gas to the adsorbent bed, so as to further repressurize the adsorbent bed from the equalization pressure toward the higher pressure, while controlling the flow so that the pressure in the bed approaches the higher pressure within a repressurization time interval,(H) cyclically repeating steps (A) to (G).