초록 ▼

Apparatus particularly applicable to the drying of gases is provided for downflow or upflow adsorption of one or more first gases from a mixture thereof with a second gas to reduce the concentration of first gas in the mixture to below a permissible maximum concentration, having at least two sorbent

Apparatus particularly applicable to the drying of gases is provided for downflow or upflow adsorption of one or more first gases from a mixture thereof with a second gas to reduce the concentration of first gas in the mixture to below a permissible maximum concentration, having at least two sorbent beds, of which one is on adsorption while the other is being regenerated, and pneumatically operated valves for flow control of gas through the beds for adsorption and for regeneration. An overriding control such as a timer or a microprocessor programmed to control the regeneration time and purge flow fixes the cycling time, and switches the adsorbent beds at the end of each cycle period.

대표청구항 ▼

Gas fractionating apparatus for reducing the concentration of one or more first gases in a mixture thereof with a second gas to below a limiting maximum concentration thereof in the second gas, by passing the mixture in contact with and from one end to another end of one of two beds of a sorbent hav

Gas fractionating apparatus for reducing the concentration of one or more first gases in a mixture thereof with a second gas to below a limiting maximum concentration thereof in the second gas, by passing the mixture in contact with and from one end to another end of one of two beds of a sorbent having a preferential affinity for the first gas, adsorbing first gas thereon to form a gaseous effluent having a concentration thereof below the maximum, and forming a concentration gradient of first gas in the bed progressively decreasing from one end to the other end as the adsorption continues and an increasing concentration of first gas in the bed defining a concentration front progressively advancing in the bed from one end to the other end as sorbent capacity therefor decreases; while passing a purge flow of gaseous effluent through the other of the two beds of sorbent to desorb first gas adsorbed thereon, and reverse the advance of the concentration front of first gas in the bed, regenerating the other bed for another cycle of adsorption; and then periodically interchanging the beds so that alternately, one bed is on regeneration and the other on the adsorption portions of the cycle; comprising, as the essential components, at least two vessels for reception of sorbent beds and adapted for alternate periodic adsorption and regeneration of the sorbent beds contained therein so that one vessel is on the adsorption portion of the cycle while the other vessel is on the regeneration portion of the cycle; means for timing the elapse of selected time intervals for determining the cycling interchange of the beds between adsorption and regeneration and giving a signal; at least one pneumatically-operated flow control valve movable between flow-open and flow-closed positions with one of the opening and closing movements of the valve being controlled by gas pressure at a pilot gas port; cycling control means responsive to the signal given by the timing means and including a pilot gas line tapping a source of pressurized gas for controlling one of the opening and closing movements of the valve by application of gas pressure via the pilot gas line to the valve; means biasing the valve in the other of the closed and open positions; opposed sides of the valve being in communication with upstream and downstream gas pressure in the line controlled by the valve and one of these sides being in communication with the pilot gas port; the cycling control means in response to the signal quickly applying a sufficient differential pressure across the valve via the pilot gas line to exceed a predetermined minimum overcoming the prevailing system pressure differential at the valve, so that the valve is moved to one of the flow-open and flow-closed positions, thereby effecting interchange of the beds in response to actuation by the cycling control means and responsive to differential pressure thereacross, and upon interruption of such application of gas pressure via the pilot gas line the valve will move into the other of the closed and open positions under the prevailing system pressure differential across the valve. Gas fractionating apparatus for reducing the concentration of one or more first gases in a mixture thereof with a second gas to below a limiting maximum concentration thereof in the second gas, by passing the mixture in contact with and from one end to another end of one of two beds of a sorbent having a preferential affinity for the first gas, adsorbing first gas thereon to form a gaseous effluent having a concentration thereof below the maximum, and forming a concentration gradient of first gas in the bed progressively decreasing from one end to the other end as the adsorption continues and an increasing concentration of first gas in the bed defining a concentration front progressively advancing in the bed from the one end to the other end as sorbent capacity therefor decreases; while passing a purge flow of gaseous effluent through the other of the two beds of sorbent to desorb first gas adsorbed thereon, and reverse the advance of the concentration front of first gas in the bed, regenerating the other bed for another cycle of adsorption; and then periodically interchanging the beds so that, alternately, one bed is on regeneration and the other on the adsorption portions of the cycle; comprising, as the essential components, at least two vessels for reception of sorbent beds and adapted for alternate periodic adsorption and regeneration of the sorbent beds contained therein so that one vessel is on the adsorption portion of the cycle while the other vessel is on the regeneration portion of the cycle; means for controlling and actuating pneumatically at selected time intervals the cycling interchange of the beds between adsorption and regeneration; at least one pneumatically operated flow control valve effecting interchange of the beds in response to actuation by the cycling control means and responsive to differential pressure thereacross, movable whenever so actuated at the selected time between flow-open and flow-closed positions only according to the controlled application thereto of a predetermined pilot gas pressure by the cycling control means, overcoming the prevailing system pressure differential at the valve, whereby upon such controlled application of gas pressure by the control means the valve will move into one of the closed and open positions, and upon interruption of such application the valve will move into the other of the closed and open positions under the prevailing system pressure differential across the valve, thereby effecting interchange of the beds, one of the opening and closing movements of the valve being controlled by gas pressure at a pilot gas port, applied against the face of a spring-biased piston attached to the valve, the spring biasing the valve in the one of the closed and open positions; opposed faces of the piston being in communication with upstream and downstream gas pressure in the line controlled by the valve, and one of these faces being in communication with the pilot gas port, whereby upon a sufficient differential pressure across the piston, supplemented to exceed a predetermined minimum via the pilot gas port under the control of the cycling control means, the piston is moved to one of the open and closed positions; and a dump control exhaust valve that regulates or limits exhaust flow from a sorbent bed during depressurization after adsorption and prior to regeneration, reducing noise and dump flow rate and sorbent bed churning and abrasion during depressurization.