GB1589757A

GB1589757A - Single bed adsorption separator apparatus

Info

Publication number: GB1589757A
Application number: GB12073/78A
Authority: GB
Original assignee: Bendix Corp
Current assignee: Bendix Corp
Priority date: 1977-04-04
Filing date: 1978-03-28
Publication date: 1981-05-20
Also published as: FR2386335B1; IT1093984B; AU3489578A; IL54375A0; DE2814442A1; CA1120411A; JPS53125268A; FR2386335A1; AU517879B2; IT7821780A0; IL54375A; ES468527A1

Description

(54) SINGLE BED ADSORPTION SEPARATOR APPARATUS (71) We, THE BENDIX CORPORATION, a corporation organised and existing under the laws of the State of Delaware, United States of America, of Bendix Center, Southfield, Michigan 48076, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following state ment: - This invention relates to an apparatus for the separation of a product effluent from a fluid mixture through seqential adsorption and desorption in a single bed of adsorption particles.

Any component in a fluid mixture having adsorbate/adsorbent isotherms different from the other components in the fluid mixture can be separated from the fluid mixture, the component being attracted into pores or onto rough surfaces of the adsorption particles. The physical adsorption of the component in the pores increases with increasing pressure and/or decreasing temperature and is reversed by lowering the pressure and/or increasing the temperature. Since adsorption is exothermic and desorption is endothermic the most efficient separation occurs if the thermal energy in the system is conserved and balanced between the two steps. However, because of the energy required to provide a thermal contribution to the separation process currently available, fluid separation such as disclosed in U.S. Patent No. 2,944,627 only employs the use of pressure in the separation process.

The separator disclosed in U.S. Patent No. 2,944,627 employs two beds of adsorption particles which are alternately connected to a source of fluid mixture under pressure. Adsorption takes place in one bed at an elevated pressure while the other bed is desorbed at a lower pressure. By alternating the operation of the beds, a continuous flow product effluent is produced. However, in purging the component from the bed of adsorption particles on desorption, it is necessary to utilize up to 75 percent of the product effluent produced by the bed of adsorption particles on adsorption to produce a desired purity in the product effluent. The reasons for such inefficiency is that the exothermic heat of adsorption is displaced and not readily available to desorption; and desorption flow paths are long and highly restrictive at the desired operational pressures.

Therefore, before such fluid mixture separators are acceptable for many processes of industry, the overall efficiency thereof needs to be improved. Such an improved fluid mixture separator would be beneficial in the separation of oxygen from air to improve biological, physiological, chemical and combustion processes which use oxygen. For instance, hydrocarbon fuel use is relatively inefficient due to the incompleteness of fuel oxidation (burning) and the thermal/thermodynamic management of the burning process. It has been determined that the actual energy output of natural gas or fuel oil in heating systems or gasoline in internal combustion engines could be increased about 30% by burning the fuels with air that is oxygen enriched.

Through experimentation it has been determined that the overall efficiency of pressure swing, adsorption-desorption fluid separators would improve with better fluid dynamics and thermal energy conservation.

Fluid dynamics of the separator apparatus would improve if the length of the bed adsorption particles and fliud flow path were selected such that with a single gas exposure pass, all the separatable molecules in the fluid mixture would have adequate exposure to an adsorption surface.

Whereas, the thermal energy in the system would improve if the exothermic heat of adsorption were retained within the bed of adsorption particles to provide endothermic heat for desorption.

It is, therefore, an essential object of the present invention to design a separator apparatus which conserves exothermic heat during adsorption to provide endothermic heat which enhances desorption and thereby maintains a substantially thermal equi librium within a bed of adsorption particles.

According to one aspect of the invention there is provided an apparatus for separating a product effluent from a fluid mixture, for instance oxygen from atmospheric air, comprising a housing having a bore therein with a first port connected to a source of fluid mixture through an inlet check valve, a second port connected to a product effluent receiver through an outlet check valve, and a third port connected to a discharge conduit through a further outlet check valve, and further comprising a bed of adsorption particles located in said bore and adapted to retain one or more components present in the fluid mixture while allowing said product effluent to flow therethrough, said apparatus further including a piston member reciprocally received within the housing bore which it divides into a pressurization chamber communicating with the first port and an expansion chamber communicating with the third port, and said piston member further defining a retention chamber in which the bed of adsorption particles is located, a control chamber communicating with the said retention chamber and also communicable with either said pressurization chamber or said expansion chamber through respective valve means, and a header chamber communicating with said retention chamber and also communicable with the second port, the arrangement being such that said piston member when reciprocating in said bore pressurizes a predetermined volume of the fluid mixture in said pressurization and control chambers while expanding any fluid in said expansion chamber during a first stroke of the piston member, said pressurized fluid thus flowing through the retention chamber where said one or more components are retained in the bed of adsorption particles while said product effluent collects into said header chember, and that a portion of said product effluent is then permitted to flow back through said retention chamber to purge the bed of adsorption particles from said one or more components and to flow with the desorbed component(s) to said control chamber for expanding into said expansion chamber during a second stroke of the piston member while a predetermined volume of fluid mixture is drawn into said pressurization chamber to complete a cycle of operation.

During the adsorption mode of the operational cycle which corresponds to the first stroke of the piston member, a valve cooperating with the second port prevents and delays the product effluent from being communicated from the header chamber through the second port until a saturation or active adsorption fluid pressure level is developed in the bed of adsorption particles. Further valves cooperating with the first and third ports, respectively, prevent the fluid mixture present in the pressurization chamber from escaping during the first stroke of the piston member and allow the mixture of product effluent and purged component present in the expansion chamber to flow into the discharge conduit during the second stroke of the piston member which corresponds to the desorption mode of the operational cycle.

Thus, the thermal energy created by the piston member in compressing the fluid mixture complements the thermal activity in the bed of adsorption particles to maintain the separator apparatus at a substantial thermal equilibrium between the adsorption and desorption cycles of operation.

In a preferred embodiment of the invention, the piston member includes a first wall spaced apart from a second wall by an outer cylindrical perforated member defining a header chamber with the housing bore and by an inner tubular performated member defining a control chamber therewithin, and the retention chamber is confined between said first and second walls, said cylindrical member and said tubular member. The control chamber formed within said tubular member further communicates with the pressurization chamber and with the expansion chamber through openings formed in the first and second walls respectively, said openings being alternately covered and discovered as the piston member reciprocates in the housing bore. To this effect, said openings cooperate with first and second closure members respectively which are fixedly carried on a linkage member extending through the piston member for reciprocating same in the housing bore, and said closure members are spaced apart somewhat more than the walls of the piston member. There may further be advantageously provided a perforated sleeve adjacent the cylindrical member for restricting the flow of the product effluent into the header chamber during the first stroke of the piston member to reduce the time required to generate an active adsorption pressure of the fluid mixture in the bed of adsorption particles and to meter the purge flow into the expansion chamber during the second stroke of the piston member.

According to a further aspect of the invention there is provided an apparatus for separating a product effluent from a fluid mixture, for instance oxygen from atmospheric air, comprising a housing having a bore therein with a first port connected to a source of fluid mixture through an inlet check valve, a second port connected to a product effluent receiver through an outlet check valve, and a third port connected to a discharge conduit through a further outlet check valve, and further comprising a bed of adsorption particles fixedly located in said bore and adapted to retain one or more components present in the fluid mixture while allowing said product effluent to flow therethrough, the bed dividing the housing into a pressurization chamber communicating with the first port and an expansion chamber communicating with the third port, said apparatus further including two spaced apart pistons carried on a common push rod on either side of the bed of adsorption particles, the first piston being located in the pressurization chamber for compressing the fluid mixture during a first stroke of said pistons corresponding to the adsorption mode of the operational cycle and for drawing a predetermined volume of fluid mixture into said chamber during a second stroke of said pistons corresponding to the desorption mode of the operational cycle, and the second piston being located in the expansion chamber for expanding into said chamber a mixture of product effluent and purged component during the first stroke of said pistons and for evacuating said mixture through the third port during the second stroke of said pistons, and wherein said bed of adsorption particles is retained between a control chamber communicable with said pressurization chamber during the first stroke and with said expansion chamber during the second stroke and a header chamber which is communicated to the second port.

The invention will now be described by way of example with reference to the accompanying drawings in which: - Figure 1 is a sectional view of an adsorption/desorption separator apparatus made according to the principles of the invention disclosed herein; Figure 2 is a sectional view taken along line 2-2 of Figure 1; Figure 3 is a sectional view of the separator apparatus illustrated in Figure 1 showing the purge mode of operation; Figure 4 is a sectional view of the separator apparatus illustrated in Figure 1 showing a pressurizing mode of operation; Figure 5 is a sectional view of the separator apparatus illustrated in Figure 1 showing a product effluent mode of operation; Figure 6 is a sectional view of the separator apparatus illustrated in Figure 1 showing a means for varying the adsorption time period of a single bed of adsorption particles with respect to the desorption time period in an operational cycle; Figure 7 is a sectional view of the separator apparatus in Figure 1 showing a secondary chamber for storing a portion of the product from the single bed of adsorption particles; Figure 8 is a sectional view of the separator apparatus in Figure 1 showing a means for changing the flow characteristics of a fluid mixture into the single bed of adsorption particles by minimizing the volume of a central distribution control chamber; Figure 9 is a sectional view of the separator apparatus in Figure 1 showing a means for providing a uniform flow cross section through the single bed of adsorption particles; Figure 10 is a sectional view of a fluid separator apparatus illustrating a secondary motor means for reciprocably moving a single bed of adsorption particles in a bore; Figure 11 is a sectional view of a separator apparatus illustrating a secondary means of controlling the communication between a single bed of adsorption particles, the pressurizing, and evacuation chambers; Figure 12 is a sectional view of a fluid separator apparatus having a fixed bed of adsorption particles located in a bore between a pressurizing and evacuation piston; Figure 13 is a sectional view of a separator apparatus illustrating a means for sequentially operating a control valve prior to a change in direction of a reciprocal movable piston to assure that adsorption of a bed of adsorption particles terminates prior to desorption; and Figure 14 is a graph illustrating the fluid pressure characteristics in the pressurizing chamber and expansion chamber of the separator apparatus in Figure 1.

The separator apparatus 10 illustrated in Figure 1 is adapted to separate either nitrogen or oxygen from air depending on the ultimate use of the resultant product effluent. The separator apparatus 10 can be used to separate a component from a fluid mixture to produce a product effluent whenever a component in the fluid mixture is attracted to an adsorption particle in a pressurization increase cycle and extracted from the adsorption particle during a purge and pressure decrease cycle.

The separator apparatus 10 shown in Figure 1 includes a housing 12 formed by attaching end plates 16 and 18 to a cylindrical body 20 and a motor member 23.

The cylindrical body 20 has a bore 14 located therein. The housing has a first port 24, a second port 26 and a third port 28 for connecting the bore 14 with a source of fluid mixture through conduit 30, a product effluent responsive member through conduit 32, and a discharge conduit 34.

A piston member 22 is located in bore 14 to establish an expansion chamber 36 adjacent port 28 and a pressurization chamber 38 adjacent port 24. The piston member has a first wall 40 separated from a second wall 42 by a cylindrical member 44 to establish a retention chamber 52 therein. The cylindrical member 44 has a groove 46 (see Figure 2) located between lands 48 and 50 and with the housing 20 establishes a header chamber 54 in bore 14.

The cylindrical member 44 has a series of radial openings 56 located therein for connecting the retention chamber 52 with the header chamber 54. A restrictive sleeve 58 having a radial opening 60 of a different size and at a different interval than radial openings 56, is attached to the cylindrical member 44 to further limit the communication from the retention chamber 52 into the header chamber 54.

A tube 61 is located along the axial cen ter of the first and second walls 40 and 42 to establish a control chamber 62. Tube 61 has a series of openings 64 for connecting the retention chamber 52 with the control chamber 62. The first wall 40 has a series of openings 66 surrounding an axial opening 68 for connecting the pressurizing chamber 38 with the control chamber 62.

The second wall 42 has a series of openings 70 surrounding an axial opening 72 for connecting the expansion chamber 36 with the control chamber 62. Guides 74 and 76 are connected to the first and second walls 40 and 42 to provide a bearing surface for stem 78. Stem 78 connects a first face member 80 with a second face member 82 on a control valve 85. The control valve 85 regulates the communication of fluid mixture and product effluent-component fluid mixture through the control chamber 62.

Second valve face member 82 of the control valve 85 is attached to push rod 84 which extends through a bearing seal arrangement 86 in end plate 16.

A pivotal linkage 88 connects push rod 84 with a flywheel 90 located on shaft 92 of the motor member 23. The shaft 92 of the motor member 23 upon rotation provides piston 22 with reciprocal motion.

Depending on the product effluent desired, the retention chamber 52 is filled with adsorption particles 94 such as a zeolite. It is well known in the separator arts such as described in U.S. Patent 3,880,616 that when oxygen is the desired product effluent, a zeolite having a pore size of approximately 4.8 Angstroms is selected for the adsorption material.

In order to assure that the adsorption particles 94 remain in the retention chamber 52, filter systems 96 and 98 are located between the cylindrical member 44 and tube 61, respectively.

As best illustrated in Figure 2, filter systems 96 and 98 have fibrous mat or coarse felt filters 100 and 102 located adjacent the adsorption particles, and a paper, screen or foam filters 104 and 106 located adjacent the cylindrical members 44 and tube 61, respectively.

In addition, plastic fibers 99 are mixed throughout the bed of adsorption particles to hold the individual particles in a substantially fixed position. The plastic fibers 99 absorb the shock forces caused by the pressurized fluid mixture and product effluent acting on the particles to reduce rubbing and thereby maintain the structural unit of the bed.

The communication of fluid mixture into the separator 10 is controlled by a first valve 108 which is attached to end plate 18. The first valve 108 which surrounds port 24 has a spring 110 which acts on and urges face 112 toward a seat 114 to only permit the fluid mixture to flow in one direction from conduit 30 into the pressur izing chamber 38.

A second valve 116 attached to the cylindrical member 20 and surrounding port 26 has a spring 118 which acts on and urges face 120 toward seat 122 to prevent the flow of the product effluent through the second port 26 when ever the fluid pressure in the bore is below a predetermined active adsorption or saturation level.

A third valve 124 attached to end plate 16 and surrounding port 28 has a spring 126 which urges face 128 against a seat 130 to prevent the communication from the conduit 34 into the expansion chamber whenever the fluid pressure in the expansion chamber is below that in the discharge conduit.

The end plate 16 has an orifice 132 therein with a size and/or adjustment such that a resulting low pressure can be produced in the expansion chamber 36 to establish a pressure differential for flowing a product effluent from the header chamber 54. The flowing produce effluent purges a component into the expansion chamber 36 during the desorption part of the operational cycle to cleanse the bed of adsorption particles.

MODE OF OPERATION OF THE INVENTION The separator apparatus 10 shown in Figure 1 is shown in a condition whereby an oxygen enriched product effluent is produced from the surrounding environment.

The motor member 23 supplies shaft 92 with a rotational torque which rotates flywheel 90. As flywheel 90 rotates end 89 of linkage member 88 pivots on pin 87 and moves in an arcuate path, however, end 91 pivots on pin 93 and provides push rod 84 with a linear input force which moves piston member 22 back and forth in bore 14.

As shown in Figure 1, linkage 88 acting through push rod 84 has moved end face 80 against the wall 40 to prevent communication through openings 66 from the pressurizing chamber 38 into the control chamber 62. With openings 66 closed communication of pressurized fluid mixture to the bed of adsorption particles 52 is interrupted and the distribution of the product effluent from conduit 32 is terminated. The fluid pressure in the bed of adsorption particles at this time is in operational cycle as illustrated by point 140 on line 142 in Figure 14. Valve 108 remains closed until the fluid pressure in the pressurizing chamber 38 is less than the fluid pressure in the fluid mixture in conduit 30. Thereafter, further movement of the piston member 22 draws a fixed volume of the fluid mixture into the pressurizing chamber 38 by overcoming spring 110 to unseat face 112 from seat 114.

Prior to the closing of communication from the pressurizing chamber 38 to the control chamber 62, the fluid pressure in the expansion chamber 36 reaches a level indicated by point 144 on line 146.

Immediately preceding the closure of the communication into the control chamber 62 through passages or openings 66, push rod 84 moves the second face member 82 away from openings 70 as shown in Figure 1 to allow communication from the control chamber 62 into the expansion chamber 36.

The fluid mixture in the control chamber 62 initially flows into the evacuated space in the expansion chamber.

Thereafter, the product effluent in the header chamber 54 reverses its flow direction and flows through openings 60 in the resistor plate 58 and openings 56 in the cylindrical wall or member 44 into the bed of adsorption particles. The fluid pressure in the bed of adsorption particles by this time is below the saturation or active pressure level and the component part of the fluid mixture (nitrogen where air is the fluid mixture) is released from the surface adorption bond and transmitted by free flow and the product effluent to the control chamber 62 for distribution to expansion chamber 36.

The product effluent continues to flow and transmit the component into the expansion chamber 36 until an equilibrium pressure illustrated by point 148 on line 146 in Figure 14 occurs. Thereafter, the fluid pressure in the expansion chamber increases and at a point 150 shown in Figure 14 is equal to the fluid pressure in the discharge conduit 34, at this time piston 22 assumes a location shown in Figure 3. Piston 22 continues to move in bore 14 toward the expansion chamber and creates a pressurizing force sufficient to overcome spring 126 and expel the product effluent and component from the expansion chamber 36 into the discharge conduit 34.

At the top of the stroke of the piston member 22, illustrated in Figure 4, push rod 84 moves the second valve face 82 against wall 42 to interrupt communication from the control chamber 62 to the expansion chamber 36. At this time the fluid pressure in the bed of adsorption particles 52, control chamber 62, and header chamber 54 is equal to point 152 in Figure 14.

Push rod 84 acts on Iwall 42 to move the piston member 22 toward the pressurizing chamber 38 to pressurize the fixed volume of fluid mixture (air) therein. The fluid pressure built up in the pressurizing chamber 38 and bed of adsorption particles follows line 142. When wall 40 of the header chamber 54 moves past port 26, the header chamber 54 is then brought into communication with the second port 26. During this fluid pressure build up, the fluid mixture is communicated through openings 66 into the control chamber 62 for distribution to the bed of adsorption particles in retention chamber 52.

The spring 118 in the second valve 116 is selected to allow communication of the product effluent in the header chamber 54 to flow past seat 122 when the saturation or active adsorption pressure level, illustrated by point 154 in Figure 14 is achieved in the bed of adsorption particles 52.

Thereafter, the piston member 22 continues to move toward the pressurization chamber 38. However, the fluid pressure level therein remains constant. The thermal energy generated in compressing the fluid mixture in the pressurizing chamber continues and is transmitted with the presur- ized fluid mixture to the bed of the adsorption particles in retention chamber 52 to aid subsequently in the desorption of the component therein.

Upon closure of the communication between the control chamber 62 and the expansion chamber 36, valve 124 interrupts flow through port 28. As piston member 22 moves toward the pressurizing chamber, the residual product effluent and component therein is expanded and pressure level illustrated by line 146' created.

At the bottom of the stroke of the piston member 22, push rod 84 again moves the first face member 80 against wall 40 and allows the product effluent in the header chamber 54 to purge the component from the single bed of adsorption particles in the retention chamber 54.

This cyclic operation continues as long as the motor member 23 provides the piston member 22 with reciprocating motion.

Under some conditions it may be desirable to connect a plurality of piston members 22 to the flywheel 90 since the motor 23, as illustrated in Figure 1, is only operating at approximately 50 X of its effective power producing efficiency. Such a scheme could be used to provide a continuous product effluent flow from conduit 32.

In the embodiments of the separator apparatus disclosed in the remaining figures in the sheets of drawings, like elements are identified by the same numerals as in Figure 1.

In Figure 6 the housing of separator apparatus 210 has included therein an operational limiter valve 150 and a relief valve 152. It has been found through experimentation that the time involved for an adsorbent particle in the bed of adsorption particles to adsorb a component onto its surface takes less time than to desorb the component therefrom. Therefore, under some conditions it is necessary to vary the adsorption mode of operation with respect to the desorption mode of operation. To achieve this variance in the operational cycle in the separator apparatus 10, an operational limiter valve 150 is designed to reduce the time period that the pressurized fluid mixture is communicated to the control chamber 62 from the pressurizing chamber 38.

The operational limiter valve 150 includes a sleeve 154 with an annular face 156 and a bearing surface 158. The bearing surface 158 is located in bore 160 extending from port 24. A spring 162 acts on the bearing surface and moves the same into engage ment with a stop or snap ring 164.

When piston member 22 moves toward the pressurizing chamber 38, face 156 engages the wall 40 and inhibits the communication from the majority of the pressurizing chamber 38 into the control chamber 62 through openings 66. The piston member 22 continues to move to the top of the stroke without any further substantial amount of the fixed volume being communi catch to the single bed of adsorption particles in the retention chamber 52.

Aftcr the engagement of face 156 and wall 40, the fluid pressure in the pressurizing chamber 38 continues to increase requiring a relief valve 152 to assure that the housing 20 and associated end plate 18 are not damaged. The relief valve 152 ineludes a dise 166 resiliently held against a seat 168 by a spring 170. The force of the spring 170 is such that a force greater than point 154, shown in Figure 14, is required to move the face 166 away from the seat 168 to provide a flow path to the atmosphere.

The purge cycle of this separator apparatus is identical to that in Figure 1 and therefore docs not need any further explanation.

The separator apparatus 310 disclosed in Figure 7 is identical to that in Figure 1 with the exception of a secondary chamber 172 connected to the housing 20 for providing the header chamber 54 with an auxiliary volume of product effluent to purge the component from the bed of adsorption particles and to assure that the flow of the product effluent through the bed of adsorption particles does not follow a flow path directly toward port 26 but is equally distributed to the header chamber 54.

The secondary chamber 172 includes a housing 174 with a neck 176 thereon which is attached to port 178 by threads.

During pressurizing of the fluid mixture in chamber 38, the resultant product effluent flows through the bed of adsorption particles, through the bed or restrictor plate 58 into the chamber 54. The product effluent flows from the header chamber 54 into the secondary chamber 172. When the second valve 116 opens the product effluent flows through conduit 32 for distribution to the product effluent 32 for responsive device.

When push rod 84 moves the first con trol face rod 80 against the wall 40 and the second control face 82 away from wall 42, as shown in Figure 7, the product effluent in the secondary chamber 172 and header chamber 54 flows through opening 60 in restrictor plate 58 to purge the bed of adsorption particles of the component retained thereon. This purge portion of the cycle continues until the pressure in the secondary chamber 172, header chamber 54, retainer chamber 52, control chamber 62 and expansion chamber 36 are equal. The extra volume of product effluent present in secondary chamber 172 provides an additional fluid volume required to remove some components from an adsorbent surface of the adsorption particles.

In addition, a flapper valve 180 atttached to the wall 42 is designed to close when- ever a positiv tion particles 186.

The conical shaped retention chamber 1 88 has a first wall 190 attached to wall 40 and a second wall 192 attached to wall 42.

The resulting throat 194 is located adjacent the cylindrical member 44. Passages 196 and 198 connect the header chamber 54 with a purge chamber 200 located between the walls 40 and 42.

In operation, the pressurized fluid mixture flows into the bed of adsorption parctiles and uniformly raises the pressure level therein. The product effluent resulting therefrom flows into the header chamber 54 and through passages 196 and 198 for distribution to the purge chamber 200.

As shown in Figure 9, when the push rod 84 moves the face member 80 against wall 40, communication through passages is interrupted and the product effluent in the purge chamber 200 flows into header chamber 54 for distribution through the bed of adsorption particles to purge or desorb any component adsorbed thereon in the adsorption part of the operational cycle. This added volume of product effluent assures that the bed of adsorption particles is relatively free of the component at the beginning of the pressurizing part of the operational cycle.

The separator apparatus 610 disclosed in Figure 10 has a rotary input shaft 92 to develop the reciprocating motion of the piston 22 in bore 14. End plate 16 has first and second projections 220 and 222 extending therefrom. First and second axles 224 and 226 are attached to the end plate 16 which are located adjacent projections 220 and 222 in a plane perpendicular to the cylindrical body 20. Hubs 234 and 236 are located on axles 224 and 226 to align gears 230 and 232 in a plane parallel to bore 14. A ring gear 238 attached to wall 42 is brought into engagement with gears 230 and 232 by a spring 240 on splined linkage 246. The splined linkage 246 has a first shaft 242 and a second shaft 244. The first shaft 242 has a first splined end 248 and a second splined end 250. Splined end 250 is located in a splined section 258 on guide 76. Splined end 248 telescopes into a corresponding splined end 252 on the second shaft 244. A gear 254 connects shaft 244 with worm gear 258 on shaft 92.

In operation, a rotative torque supplied to shaft 92 causes a corresponding rotative torque to be applied to shaft 244. The splined linkage 246 transmits torque from shaft 244 directly into shaft 242 which rotates the piston member 22. As piston member rotates, ring gear 238 engages eccentric gears 230 and 232. Since spring 240 holds the ring gears 238 in contact with eccentric gears 230 and 232, the piston member reciprocates in bore 14 from the bottom of a stroke in the expansion chamber 36 to the top of a stroke in the pressurizing chamber 38. The desorption and adsorption modes of an operational cycle of the single bed of adsorption particles when brought into communication with a pressurized fluid mixture to produce a product effluent and a lower pressure chamber to purge the bed is the same as that described with respect to Figure 1.

The separator apparatus 710 shown in Figure 11 is identical to the separator apparatus disclosed in Figure 1 with the exception of the first and second control valves 260 and 262.

The first control valve 260 has a housing 264 attached to wall 40 with a bore 266 located therein connected to pressurizing chamber 38 through opening or passage 268.

A piston 270 located in bore 266 has a ball poppet, or plate 272 on the end thereof which is urged toward a seat 274 by a spring 276. A cross bore 278 connects bore 266 to the control chamber 62.

The second control valve 262 has a housing 280 attached to wall 42 with a bore 282 located therein connected to the control chamber 62 through opening or passage 284.

A piston 286 located in bore 282 has a ball poppet or plate 288 on the end thereof which is urged toward a seat 290 by a spring 292. A cross bore 294 connects bore 282 with the expansion chamber 36.

In operation, when the fluid pressure in the bed of adsorption particles reaches a peak predetermined pressure level and acts on ball 288, the piston is moved away from seat 290. When the ball 288 moves away from the seat 290, the fluid pressure acts on the piston 286 and rapidly moves and holds ;the piston 286 against stop 296 to allow the product effluent to purge the bed of adsorption particles in retainer chamber 52 of the component absorbed on the surface thereof.

When ball 288 of piston 286 is moved away from seat 290, a pressure drop occurs in the control 62 such that spring 276 moves ball 272 against seat 274 to interrupt communication from pressurizing chamber 38 into the control chamber 62.

As piston member 22 approaches the bottom of its stroke, a positive pressure is created in expansion chamber 36. This positive pressure allows spring 294 to seat ball 288 on seat 290 to interrupt communication to the expansion chamber 36 from the control chamber 62. Thereafter the positive pressure acts to open valve 124 and expel the product effluent and component through the discharge port without any back flow into the control chamber 62.

When piston member 22 reaches the bottom of its stroke, the direction is reversed and face 40 begins to pressurize the fixed volume of the fluid mixture in the pressuriz ing chamber 38. When a predetermined fluid pressure is developed in the pressuriz ing chamber 38, ball 272 moves away from seat 274 and thereafter acts on piston 270 which is urged against stop 265. Thereafter, the pressurized fluid mixture flows into the control chamber 62 for distribution through the bed of adsorption particles in retention bed 52.

The second valve 116 prevents any pro duct effluent communicated to header cham ber 54 until an active adsorption fluid pres sure level is achieved in the bed of adsorp tion particles. Thereafter the product eff luent flows past seat 122 through conduit 32 for distribution to the product effluent re sponsive device.

When a negative fluid pressure level is achieved in expansion chamber 36 through the expansion of the product effluent and component therein, the fluid mixture fluid pressure acts on ball 288 to move the piston away from seat 290 and opens communica tion between the control chamber 62 and the expansion chamber and begin a new cycle of operation as the piston 22 returns from the top of the stroke.

The separator apparatus 810 disclosed in Figure 12 has a single bed of adsorption particles located between walls 40 and 42 in a fixed position adjacent the port 26. A first piston 300 separates the bore 14 between wall 40 and end plate 18 into a supply chamber 302 and a pressurizing chamber 304. A second piston 306 separates the bore 14 between wall 42 and end plate 16 into an expansion chamber 308 and an atmos pheric chamber 312.

A first valve 314 attached to the first piston 300 controls the flow of the fluid mix ture from the supply chamber 302 into the pressurizing chamber 304. Valve 314 has a disc 316 urged toward a seat 318 by a spring 320.

A second valve 322 located in the con trol chamber 62 has a split spool 324 fric tionally carried on push rod 84 to control the communication between the control chamber 62, the pressurizing chamber 304, and the expansion chamber 308.

A discharge valve 326 has a face 328 which is resiliently positioned away from the second piston 306 by spring 330.

The separator apparatus 810 in Figure 12 is illustrated in the adsorption part of the cycle. Push rod 84 pulls the first and second pistons 300 and 306 toward the pressurizing chamber 304 and the atmospheric chamber 312. As the piston moves in the adsorption mode, valve 108 opens and allows a fixed volume of fluid mixture to flow into the supply chamber 302. At the same time, the fluid pressure of the fluid mixture in the pressurizing chamber 304, the control cham ber 62, the retention chamber 52 and header chamber 54 increases while the fluid pres sure in the expansion chamber 308 de creases to create a pressure differential across spool 324. This pressure differential acts on and moves the spool against wall 42 to prevent communication from the control chamber 62 to the expansion cham ber.

The fluid pressure in the pressurizing chamber 304 increases until an active ad sorption pressure level develops in the bed of adsorption particles. Thereafter, spring 118 is overcome and face 120 moves away from seat 122 to allow the product eff luent in header chamber 54 to flow into conduit 32 for distribution to the product effluent responsive device.

At the top of the stroke of the push rod 84, push rod 84 moves pistons 300 and 306 toward the supply chamber 302 and expansion chamber 308. Spool valve 324 is frictionally carried on push rod 84 and at the top of the stroke moves away from openings 72 into engagement with open ings 66 to terminate communication with the presurizing chamber 304 into the con trol chamber 62 and initiate communica tion from the control chamber 62 to the expansion chamber 308. The product eff luent in the header chamber 54 flows through the bed of adsorption particles in retainer chamber 52 and purges any com ponent absorbed on the surface thereby flowing toward the expansion chamber 308 because of the negative or lower fluid pres sure contained therein.

The product effluent and component flow into the expansion chamber 308 un til the fluid pressure in the header cham ber 54, retention chamber 52, control chamber 62, and expansion chamber 308 are equal.

At this point in time, face 328 engages housing 42 and interrupts the communica tion between the control chamber 62 and the expansion chamber 308. Further move ment of piston 306 toward wall 42 creates a positive pressure which expels the pro duct effluent and component through port 28 to the atmosphere through discharge conduit 34.

As piston 300 moves toward the supply chamber 302, spring 320 is overcome and a fixed volume of fluid mixture presented in the supply chamber flows into the pres surizing chamber 304.

At the bottom of the stroke, push rod 84 moves spool valve 324 against wall 42 to again initiate the adsorption mode in the operational cycle.

The separator apparatus 1010 disclosed in Figure 13 is identical to that in Figure 1 with the exception that the first port 24 is offset from the center line of the hous ing, a bumper member 370 is located in an axial line with push rod 84, and a plunger member 372 extends from push rod 84 to control communication between control chamber 62 and the pressurizing chamber 38 and expansion chamber 36.

The plunger member 372 has a tubular member 374 which extends through bearing surface 380 into the control chamber 62. A stem 386 attached to a first face member 388 has an end 390 which telescopingly extends into the tubular member 374. The stem 386 has a slot 392 therein through which pin 394 extends for attaching the stem 386 to the tubular member 374. A spring 396 located in the tubular member 374 urges the first face member 388 away from the first wall 40.

A second face member 378 located on the push rod 84 is urged against a stop 384 by a spring 382 to provide independent movement between the second face member 378, the second wall 42 and push rod 84.

A driving plate 399 attached to the second wall 42 provides a guide for push rod 84 to assure a seal develops across seats 397 and 398 upon engagement of the first and second face members 388 and 378 with walls 40 and 42, respectively.

A driving collar 400 having a first face 404 and a second face 402 is fixed to the push rod 84 on opposite sides of the driving plate 399. The distance between the first and second faces 402 and 404 is equal to the length of slot 392 and as such, controls the sequential engagement of the first and second face members 388 and 378 with the first and second walls 40 and 42.

The bumper member 370 includes an adjustable bolt 406 which extends through housing 16 with a head 408 attached thereto in the pressurizing chamber 38. A spring 410 holds the head 408 against a stop 412 on the end of bolt 406.

In operation, on the down stroke of the push rod 84, the first face 404 on the collar 400 engages driving plate 399 and at the same time the second face 402 engages the second face member 378 to move face 378 on to seat 397 to interrupt communication from expansion chamber 36 into control chamber 62.

At the same time, spring 396 moves the first face 388 away from the first wall 40 to allow communication from pressurizing chamber 38 into the control chamber 62.

As piston 22 moves in bore 14 the fluid pressure in the pressurizing chamber 38 increases and is communicated into the control chamber 62 for distribution to the bed of adsorption particles. The bed of adsorption particles adsorbs a component from the pressurized fluid mixture and a product effluent flows into the header chamber 54. The header chamber 54 retains the product effluent until wall 40 moves past the second port 26 and an adsorption fluid pressure level is achieved therein sufficient to overcome spring 118. Thereafter the pressurized fluid mixture pushes a corresponding volume of product effluent through the second port 26 for distribution through conduit 32.

As piston 22 approaches the end of the down stroke, surface 389 engages bumper face 408 to move face 388 toward seat 398.

Tubular member 374 continues to move as pin 394 moves in slot 392.

At the bottom of the down stroke, push rod 84 reverses direction moving face 402 on collar 400 against driving plate 399 and pin 394 against the bottom of slot 392.

During this movement, piston 22 remains stationary; however, spring 382 moves the second face member 378 away from seat 397 to initiate communication between control chamber 62 and the evacuated expansion chamber 36. At the same time, spring 410 holds the first face 388 against wall 40 to prevent communication from the pressurizing chamber 38 into the control chamber 62. Thereafter, the push rod 84 moves the piston 22 in the up stroke to draw a fixed volume of fluid mixture into the pressurizing chamber 38. As the piston 22 approaches the top of the up stroke, a positive pressure develops in the expansion chamber 36. This positive pressure acts on the second face member 378 and in opposition to spring 382 moves the second face member 378 against seat 397 to segregate the expansion chamber 36 rfom the control chamber 62. For the remainder of the upstroke, product effluent and the component purged from the bed of adsorption particles is pushed through port 28 to be disposed of through the discharge conduit 34.

Upon passing the top of the up stroke, piston 22 remains stationary for a moment as push rod 84 again moves face 404 into engagement with driving plate 399 and face 402 into engagement with the second face 378 while spring 396 moves the first face 388 away from seat 398 to initiate another cycle of operation.

Each of the separator apparatus in this invention disclosed in Figures 1-13 involve a single bed of absorption particles capable of separating a component from a fluid mixture to produce a product effluent.

However, the principals equally apply to a two-bed system wherein it is desired to conserve energy in the production of a product effluent.

WHAT WE CLAIM IS: 1. An apparatus for separating a pro

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ing, a bumper member 370 is located in an axial line with push rod 84, and a plunger member 372 extends from push rod 84 to control communication between control chamber 62 and the pressurizing chamber 38 and expansion chamber 36. The plunger member 372 has a tubular member 374 which extends through bearing surface 380 into the control chamber 62. A stem 386 attached to a first face member 388 has an end 390 which telescopingly extends into the tubular member 374. The stem 386 has a slot 392 therein through which pin 394 extends for attaching the stem 386 to the tubular member 374. A spring 396 located in the tubular member 374 urges the first face member 388 away from the first wall 40. A second face member 378 located on the push rod 84 is urged against a stop 384 by a spring 382 to provide independent movement between the second face member 378, the second wall 42 and push rod 84. A driving plate 399 attached to the second wall 42 provides a guide for push rod 84 to assure a seal develops across seats 397 and 398 upon engagement of the first and second face members 388 and 378 with walls 40 and 42, respectively. A driving collar 400 having a first face 404 and a second face 402 is fixed to the push rod 84 on opposite sides of the driving plate 399. The distance between the first and second faces 402 and 404 is equal to the length of slot 392 and as such, controls the sequential engagement of the first and second face members 388 and 378 with the first and second walls 40 and 42. The bumper member 370 includes an adjustable bolt 406 which extends through housing 16 with a head 408 attached thereto in the pressurizing chamber 38. A spring 410 holds the head 408 against a stop 412 on the end of bolt 406. In operation, on the down stroke of the push rod 84, the first face 404 on the collar 400 engages driving plate 399 and at the same time the second face 402 engages the second face member 378 to move face 378 on to seat 397 to interrupt communication from expansion chamber 36 into control chamber 62. At the same time, spring 396 moves the first face 388 away from the first wall 40 to allow communication from pressurizing chamber 38 into the control chamber 62. As piston 22 moves in bore 14 the fluid pressure in the pressurizing chamber 38 increases and is communicated into the control chamber 62 for distribution to the bed of adsorption particles. The bed of adsorption particles adsorbs a component from the pressurized fluid mixture and a product effluent flows into the header chamber 54. The header chamber 54 retains the product effluent until wall 40 moves past the second port 26 and an adsorption fluid pressure level is achieved therein sufficient to overcome spring 118. Thereafter the pressurized fluid mixture pushes a corresponding volume of product effluent through the second port 26 for distribution through conduit 32. As piston 22 approaches the end of the down stroke, surface 389 engages bumper face 408 to move face 388 toward seat 398. Tubular member 374 continues to move as pin 394 moves in slot 392. At the bottom of the down stroke, push rod 84 reverses direction moving face 402 on collar 400 against driving plate 399 and pin 394 against the bottom of slot 392. During this movement, piston 22 remains stationary; however, spring 382 moves the second face member 378 away from seat 397 to initiate communication between control chamber 62 and the evacuated expansion chamber 36. At the same time, spring 410 holds the first face 388 against wall 40 to prevent communication from the pressurizing chamber 38 into the control chamber 62. Thereafter, the push rod 84 moves the piston 22 in the up stroke to draw a fixed volume of fluid mixture into the pressurizing chamber 38. As the piston 22 approaches the top of the up stroke, a positive pressure develops in the expansion chamber 36. This positive pressure acts on the second face member 378 and in opposition to spring 382 moves the second face member 378 against seat 397 to segregate the expansion chamber 36 rfom the control chamber 62. For the remainder of the upstroke, product effluent and the component purged from the bed of adsorption particles is pushed through port 28 to be disposed of through the discharge conduit 34. Upon passing the top of the up stroke, piston 22 remains stationary for a moment as push rod 84 again moves face 404 into engagement with driving plate 399 and face 402 into engagement with the second face 378 while spring 396 moves the first face 388 away from seat 398 to initiate another cycle of operation. Each of the separator apparatus in this invention disclosed in Figures 1-13 involve a single bed of absorption particles capable of separating a component from a fluid mixture to produce a product effluent. However, the principals equally apply to a two-bed system wherein it is desired to conserve energy in the production of a product effluent. WHAT WE CLAIM IS:

1. An apparatus for separating a pro

duct effluent from a fluid mixture, for in stancc oxygen from atmospheric air, comprising a housing having a bore therein with a first port connected to a source of fluid mixture through an inlet check valve, a second port connected to a product effluent receiver through an outlet check valve, and a third port connected to a discharge conduit through a further outlet check valve, and further comprising a bed of adsorption particles located in said bore and adapted to retain one or more components present in the fluid mixture while allowing said effluent to flow therethrough, said apparatus further including a piston member reciprocably received within the housing bore which it divides into a pressurization chamber communicating with the first port and an expansion chamber communicating with the third port, and said piston member further defining a retention chamber in which the bed of adsorption particles is located, a control chamber communicating with said retention chamber and also communicable with either said pressurization chamber or said expansion chamber through respective valve means, and a header chamber communicating with said retention chamber and also communicable with the second port, the arrangement being such that said piston member when reciprocating in said bore pressurizes a predetermined volume of the fluid mixture in said pressurization and control chambers while expanding any fluid in said expansion chamber during a first stroke of the piston member, said pressurized fluid thus flowing through the retention chamber where said one or more components are retained in the bed of adsorption particles while said product effluent collects into said header chamber, and that a portion of said product effluent is then permitted to flow back through said retention chamber to purge the bed of adsorption particles from said one or more components and to flow with the desorbed component(s) to said control chamber for expanding into said expansion chamber during a second stroke of the piston member while a predetermined volume of fluid mixture is drawn into said pressurization chamber to complete a cycle of operation.

2. An apparatus according to Claim 1, wherein the piston member includes a first wall spaced apart from a second wall by an outer cylindrical perforated member defining said header chamber with the housing bore and by an inner tubular perforated member defining said control chamber therewithin, and said retention chamber being confined between said first and second walls, said cylindrical member and said tubular member.

3. An apparatus according to Claim 2, wherein the control chamber formed within said tubular member communicates with said pressurization chamber and with said expansion chamber through openings formed in said first and second walls respectively, said openings being alternately covered and uncovered as the piston member reciprocates in the housing bore.

4. An apparatus according to Claim 3, wherein said openings cooperate with first and second closure members respectively, said closure members being fixedly carried on a linkage member extending through the piston member for reciprocating same in the housing bore, and said closure members being spaced apart somewhat more than said first and second walls of the piston member.

5. An apparatus according to any of Claims 2 to 4, wherein there is further provided a perforated sleeve adjacent the cylindrical member for restricting the flow of the product effluent into the header chamber during the first stroke of the piston member to reduce the time required to generate an active adsorption pressure of the fluid mixture in the bed of adsorption particles and to meter the purge flow into the expansion chamber during the second stroke of the piston member.

6. An apparatus according to any of Claims 2 to 5, wherein plastic fibers are dispersed within the bed of adsorption particles for holding same in a substantially fixed position relative to the first and second walls of the piston member.

7. An apparatus according to any of Claims 2 to 6, wherein, in order to shorten the time period of the adsorption mode of operation with respect to the desorption mode, there is provided in the pressurization chamber a limiter valve comprising a sleeve slidably guided in the housing and urged by a spring toward the piston member so as to engage its first wall and stop communication of the pressurization chamber with the control chamber during the first stroke of said piston member.

8. An apparatus according to any of Claims 2 to 7, further including a relief chamber connected to the header chamber for storing the product effluent during the adsorption mode of operation corresponding to the first stroke of the piston member to provide a uniform flow distribution plenum for the product effluent through the bed of adsorption particles and to provide additional product effluent to purge the component from the bed during the desorption mode of operation corresponding to the second stroke of the piston member.

9. An apparatus according to any of claims 2 to 8, wherein there is further provided a flapper valve cooperating with the openings in the second wall of the piston member and responsive to a positive pressure in the expansion chamber for prevent ing the product effluent and purged component from flowing into the control chamber.

10. An apparatus according to any of Claims 2 to 9, wherein there is further provided a generally cylindrical member in the control chamber for controlling the radial size of the bed of adsorption particles to balance the fluid dynamics of the flow of the fluid mixture through said bed during the adsorption mode of the operational cycle with the flow of the product effluent and component through said bed during the desorption mode of the operational cycle.

11. An apparatus according to any of Claims 2 to 9, wherein the piston member further includes a conical housing having a base connected to the control chamber and a head connected to the header chamber, said conical housing retaining the bed of adsorption particles and providing a controlled incremental change in fluid pressure in said bed of adsorption particles during the adsorption mode of the operational cycle.

12. An apparatus according to Claim 11, further including a purge chamber between said conical housing and the piston walls, said purge chamber being connected to the header chamber for storing product effluent during the adsorption mode of the operational cycle which flows through and desorbs the component from the bed of adsorption particles during the desorption mode of the operational cycle.

13. An apparatus according to any of Claims 2 to 12, further including a first control valve connected to the first piston wall and responsive to a predetermined fluid pressure in the pressurizain chamber for allowing the fluid mixture to flow into the control chamber during the adsorption mode of the operational cycle, and a second control valve attached to the second piston wall, said second control valve being responsive to a fluid pressure differential between the control chamber and the expansion chamber for allowing the product effluent and purged component to flow into the expansion chamber during the desorption mode of the operational cycle.

14. An apparatus according to Claim 13, wherein the second valve is further secured to a linkage member engaged through the housing for directly reciprocating the piston member in the housing bore.

15. An apparatus according to any of Claims 2 to 12, further including a control valve means having a plunger extending through the housing and the walls of the piston member with a first closure member located in the pressurization chamber and a second closure member located in the expansion chamber, said first closure member engaging the first piston wall during the desorption mode of the operational cycle to prevent the product effluent and purged component from flowing into the presserization chamber, said second closure member engaging the second piston wall during the adsorption mode of the operational cycle to prevent communication between the expansion chamber and the control chamber, and said plunger being secured to the linkage means for reciprocating the piston member in the housing bore.

16. An apparatus according to Claim 15, further including an adjustable bumper attached to the housing which engages said first closure member upon termination of the adsorption mode of the operational cycle and allows the plunger to move the second closure member away from the second piston wall to initiate communication between the control chamber and the expansion chamber and allow the product effluent to purge the component from the bed of adsorption particles.

17. An apparatus according to any of Claims 2 to 16, further including a ring gear attached to one of the piston walls and eccentric gear means attached to the housing and engageable with said ring gear, a motor providing said piston member with rotative torque causing the ring gear to engage the eccentric gear and thereby move the piston member along a linear path in the housing bore.

18. An apparatus according to any of Claims 1 to 17, wherein the check valve associated with the second port preventing any product effluent from flowing through said second port until a specific fluid pressure develops in the header chamber.

19. An apparatus for separating a product effluent from a fluid mixture, for instance oxygen from atmospheric air, comprising a housing having a bore therein with a first port connected to a source of fluid mixture through an inlet check valve, a second port connected to a product effluent receiver through an outlet check valve, and a third port connected to a discharge conduit through a further outlet check valve, and further comprising a bed of adsorption particles fixedly located in said bore and adapted to retain one or more components present in the fluid mixture while allowing said product effluent to flow therethrough, the bed dividing the housing into a pressurization chamber communicating with the first port and an expansion chamber communicating with the third port, said apparatus further including two spaced apart pistons carried on a common push rod on either side of the bed of adsorption particles, the first piston being located in the pressurization chamber for compressing the fluid mixture during a first stroke of said pistons corresponding to the adsorption mode of the operational cycle and for drawing a predetermined volume of fluid mixture into said chamber during a second stroke of said pistons corresponding to the desorption mode of the operational cycle, and the second piston being located in the expansion chamber for expanding into said chamber a mixture of product effluent and purged component during the first stroke of said pistons and for evacuating said mixture through the third port during the second stroke of said pistons, and wherein said bed of adsorption particles is retained between a control chamber communicable with said pressurization chamber during the first stroke and with said expansion chamber during the second stroke and a header chamber which is communicated to the second port.

20. An apparatus according to Claim 19, wherein the communication of said control chamber with either of said pressurization chamber and said expansion chamber is controlled by a spool valve located in said control chamber and carried in frictional engagement with the piston push rod.

21. An apparatus for separating a product effluent from a fluid mixture, substantially as described hereinabove with reference to the accompanying drawings.