CONFIGURATION FOR EXPEDITED FILLING AND EMPTYING OF AN AMINE BED

A swing bed absorption apparatus includes a bed including a bed housing including, an outer surface, an interior chamber, and a flared interior passageway fluidly connecting the interior chamber to an area located outside of the bed. The flared interior passageway includes an opening in the outer surface, a chamber opening at the interior chamber, a first portion located at the opening, the first portion being fluidly connected to the area located outside the bed through the opening, and a flared portion located at the chamber opening, the flared portion being fluidly connected to the interior chamber through the chamber opening. The flared portion connects to the interior chamber at an obtuse angle.

BACKGROUND

The subject matter disclosed herein relates generally to the field of removing carbon dioxide gas, and specifically to an apparatus for absorbing and removing carbon dioxide gas and humidity from an enclosed space.

Life support systems that are utilized in enclosed spaces such as submarines, spacecraft or space suits require the continuous removal of carbon dioxide. A regenerative carbon dioxide removal system is utilized for this purpose and commonly includes amine beds that are placed in contact with a flow of carbon dioxide laden air. The amine beds adsorb carbon dioxide from the air stream through commonly understood chemical processes and reactions.

An amine bed is utilized until it is saturated to a selected saturation level. The selected saturation level can be a saturation level where the amine bed can no longer efficiently remove carbon dioxide from an air stream or any saturation level less than the saturation level where the amine bed can no longer efficiently remove carbon dioxide from the air stream. Another amine bed is then switched into contact with the carbon dioxide laden air stream. The saturated amine bed is then desorbed to expel carbon dioxide in preparation for the next cycle.

BRIEF SUMMARY

According to one embodiment, a swing bed absorption apparatus is provided. The swing bed absorption apparatus includes a bed including a bed housing including, an outer surface, an interior chamber, and a flared interior passageway fluidly connecting the interior chamber to an area located outside of the bed. The flared interior passageway includes an opening in the outer surface, a chamber opening at the interior chamber, a first portion located at the opening, the first portion being fluidly connected to the area located outside the bed through the opening, and a flared portion located at the chamber opening, the flared portion being fluidly connected to the interior chamber through the chamber opening. The flared portion connects to the interior chamber at an obtuse angle.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the flared interior passageway further includes a straight portion interposed between the first portion and the flared portion, the straight portion fluidly connecting the first portion and the flared portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the flared portion directly connects to the first portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the flared portion is a countersink hole.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the first portion is a counterbore.

According to another embodiment, a method of manufacturing a swing bed absorption apparatus is provided. The method includes forming a bed by forming a bed housing including an outer surface and an interior chamber and forming a flared interior passageway. The flared interior passageway fluidly connecting the interior chamber to an area located outside of the bed. The flared interior passageway includes an opening in the outer surface, a chamber opening at the interior chamber, and a first portion located at the opening. The first portion being fluidly connected to the area located outside the bed through the opening. The flared interior passageway also includes a flared portion located at the chamber opening. The flared portion being fluidly connected to the interior chamber through the chamber opening. The flared portion connects to the interior chamber at an obtuse angle.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the forming the flared interior passageway further includes that a straight portion is formed. The straight portion being interposed between the first portion and the flared portion. The straight portion fluidly connects the first portion and the flared portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the forming the straight portion further includes drilling from the outer surface into the bed housing to form the straight portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the forming the flared interior passageway further includes forming the flared portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the forming the flared portion further includes machining a countersink hole from the chamber opening to form the flared portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the forming the flared portion further includes: drilling a hole in the outer surface into the bed housing to the interior chamber; inserting a backside spot face tool through the hole; extending a cutting blade from the backside spot face tool; and rotating the cutting blade to form the flared portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the flared portion is a countersink hole.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the forming the flared interior passageway further includes: forming the first portion.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the forming the first portion further includes machining a counter bore from the outer surface to form the first portion.

DETAILED DESCRIPTION

An amine bed for a swing bed absorption apparatus is typically constructed with a metal foam filled with amine-based sorbent beads. The metal foam creates a treacherous path to trap in the amine-based sorbent beads. The metal foam also serves additional functions. First, the absorbing and desorbing process includes heat transfer and so the metal foam allows the heat generated to be transferred to the adjacent amine bed. Second, having the amine-based sorbent beads touching the metal foam is beneficial from this perspective. The metal foam also acts as a structural member to be able to react loads that the assembly needs to withstand during launch and during operation. The amine beds are pressurized as compared to an external vacuum environment (such as during a spacewalk).

Upon construction of the amine beds the amine-based sorbent beads are flowed into the metal foam through a fill port and fill throughout the treacherous path of the metal foam. The metal foam decreases the area of the fill port because the foam contacts the closure bar where the fill port is located. Since the foam structure is random the percent of blockage of the fill port is variable. The filling of the amine-based sorbent beads often takes a great deal of time because it is difficult for the amine-based sorbent beads to make their way through the treacherous path of the metal foam and some certain percent of the fill port is blocked by the foam. When the amine-based sorbent beads have reached the end of their usable life the amine-based sorbent beads need to be removed from the metal foam and replaced. Embodiments disclosed herein seek to decrease the time it takes for the amine-based sorbent beads to be installed into the metal foam and removed from the metal foam by adding a conical feature to the fill port, which increases the exposed area of metal foam and results in a lower percentage of the fill port being blocked or a higher percentage of open area in the fill port

Referring now toFIG. 1, an isometric view of a swing bed absorption apparatus200is illustrated, according to an embodiment of the present disclosure. The swing bed absorption apparatus200is composed of two or more beds240. The two or more beds240are formed stacked on top of each other. The swing bed absorption apparatus200ofFIG. 1includes four beds240. It is understood that while the exemplary swing bed absorption apparatus200ofFIG. 1includes four beds240, the embodiments disclosed herein may be applicable to a swing bed absorption apparatus200with two or more beds240.

The beds240are sandwiched together by a first end portion210and a second end portion220. The first end portion210is located at a first end202of the swing bed absorption apparatus200and the second end portion220is located at a second end204of the swing bed absorption apparatus200. Each of the beds240is composed of a bed housing242that contains a metal foam and amine-based sorbent beads to absorb carbon dioxide.

Each bed housing242includes an outer surface241. Each bed housing242includes one or more openings245in an outer surface241on a first side243of the bed housing242. The openings245serve as openings to interior passageways for filling and/or emptying ports for the amine based sorbent beads. Although not visible inFIG. 1, there are also openings in the outer surface241on a second side244of the bed housing242. The second side244is located opposite the first side243.

Referring now toFIG. 2, with continued reference toFIGS. 1 and 2, a cross-sectional view of a straight interior passageway300is illustrated inFIG. 2and a cross-sectional view of a flared interior passageway400is illustrated inFIG. 3. The bed housing242forms an interior chamber250within the bed housing242. The interior chamber250is configured to contain the metal foam260and the amine-based sorbent beads500within the metal foam260. The straight interior passageway300fluidly connects the interior chamber250to an area270located outside of the bed240. The flared interior passageway400fluidly connects the interior chamber250to the area270located outside of the bed240.

The straight interior passageway300is located within the bed housing242and fluidly connects the opening245to an interior chamber250containing the metal foam260. The straight interior passageway300includes a first portion310located at the opening245and a straight portion320located at the interior chamber250. The first portion310may be a counterbore configured to receive a plug, with seals, that is attached after the amine based sorbent beads500are filled into the chamber250to keep the amine based sorbent beads500from spilling out and to allow the interior chamber250to be pressurized with respect to the exterior area270. The straight portion320may connect to the interior chamber250at a right angle α1as measured through the bed housing242, as illustrated inFIG. 2. A right angle is defined as an angle that is equal to 90 degrees. The straight portion320is fluidly connected to the interior chamber250at a chamber opening252.

The flared interior passageway400is located within the bed housing242and fluidly connects the opening245to an interior chamber250containing the metal foam260. The flared interior passageway400includes a first portion410located at the opening245and a flared portion430located at the interior chamber250. The first portion410is configured to receive a plug, with seals, that is attached after the amine based sorbent beads500are filled into the chamber250to keep the amine based sorbent beads500from spilling out and to allow the interior chamber250to be pressurized with respect to the exterior area270. The flared interior passageway400may includes a straight portion420interposed between the first portion410and the flared portion430. The straight portion420may fluidly connect the first portion410and the flared portion430. In alternate embodiment, the flared interior passageway400may not include straight portion420and the flared portion430may be directly connected to the first portion410. The first portion410may be a counterbore configured to receive a plug, with seals, that is attached after the amine based sorbent beads500are filled into the chamber250to keep the amine based sorbent beads500from spilling out and to allow the interior chamber250to be pressurized with respect to the exterior area270. The flared portion430connects to the interior chamber250at an obtuse angle α2as measured through the bed housing242, as illustrated inFIG. 3. An obtuse angle is defined as an angle that is greater than 90 degrees. The flared portion430may be a countersink hole. The flared portion430may also be any shape including a conical shape as illustrated inFIG. 3or a parabolic shape. The flared portion430may include linear side walls to form the conical shape as illustrated inFIG. 3or curvilinear sidewalls. The countersink hole may be formed by a backside spot face tool. It is understood that the flared portion may be formed by any other manufacturing process known to one of skill in the art, including, but not limited, to additive manufacturing. The flared portion430is fluidly connected to the interior chamber250at a chamber opening252.

Advantageously, by flaring out the flared interior passageway400at the chamber opening252the amine-based sorbent beads500are exposed to more surface area of the metal foam260when entering the interior chamber250and thus the amine-based sorbent beads500will both fill the metal foam260within the interior chamber250and empty the metal foam260within the interior chamber250faster than in comparison to the straight interior passageway300. This is clearly visible when comparingFIGS. 2 and 3, as the surface area SA1of the metal foam260exposed by the straight interior passageway300is smaller than the surface area SA2of the metal foam260exposed by the flared interior passageway400.

Referring now toFIG. 4, with continued reference toFIGS. 1-3, a flow chart of method600of manufacturing the swing bed absorption apparatus200is illustrated, in accordance with an embodiment of the disclosure.

The method600of manufacturing the swing bed absorption apparatus200includes forming a bed240. The bed240may be formed machining operations, drilling operations, additive manufacturing, or a combination thereof.

At block604, a bed housing242comprising an outer surface241and an interior chamber250is formed. The bed housing242may be formed through additive manufacturing and/or machining. The bed housing242may also be formed using any other manufacturing process known to one of skill in the art.

At block606, the flared interior passageway400is formed. The flared interior passageway400may be formed through additive manufacturing, machining, and/or drilling. The flared interior passageway400may also be formed using any other manufacturing process known to one of skill in the art. The flared interior passageway400fluidly connects the interior chamber250to an area270located outside of the bed240, the flared interior passageway400includes an opening245in the outer surface241, a chamber opening252at the interior chamber250, and a first portion410located at the opening245. The first portion410being fluidly connected to the area270located outside the bed240through the opening245. The flared interior passageway400also includes a flared portion430located at the chamber opening252. The flared portion being fluidly connected to the interior chamber250through the chamber opening252. The flared portion430connects to the interior chamber250at an obtuse angle α2.

The flared interior passageway400may include forming a straight portion420. The straight portion420being interposed between the first portion410and the flared portion430. The straight portion420fluidly connects the first portion410and the flared portion430. The straight portion420may not be present and the first portion410may directly connect to the flared portion430. The straight portion420may be formed by drilling from the outer surface241into the bed housing242.

Forming the flared interior passageway400may further include forming the flared portion430. The flared portion430may be formed by machining a countersink hole430a(see isometric view of countersink hole430ainFIG. 6) from the chamber opening252to form the flared portion430.

While the above description has described the flow process ofFIG. 4in a particular order, it should be appreciated that unless otherwise specifically required in the attached claims that the ordering of the steps may be varied and the order of the steps may occur simultaneously or near simultaneously, such as in layers.

Referring now toFIGS. 5-6, a method700of forming the flared interior passageway400is illustrated inFIG. 5and the flared portion430is illustrated inFIG. 6, in accordance with an embodiment of the present disclosure. At block710, a bed housing242is formed with an outer surface241and an interior chamber250.

At720, a hole290is drilled in the outer surface into the bed housing242to the interior chamber250using a drill910.

At730, a backside spot face tool920is inserted through the hole290. The backside spot face tool920includes a stem922and a cutting blade930that is extendable from the stem922. The cutting blade930may extend from the stem922and compress back into the stem922to fit through the hole290. The cutting blade930may extend from the stem once the stem922is located in the interior chamber250.

At740, the cutting blade930may be rotated to form the flared portion430. The cutting blade930may be rotated and pulled into the chamber opening252to machine away the flared portion430from the bed housing242. An isometric view of the flared portion430is illustrated inFIG. 6. In one embodiment, the cutting blade930may be rotated and pulled into the chamber opening252to machine away the flared portion430from the bed housing242all the way up to the first portion410, leaving no straight portion420. In another embodiment, the cutting blade930may be rotated and pulled into the chamber opening252to machine away the flared portion430from the bed housing242a first distance D1away from the chamber opening252, leaving a straight portion420.FIG. 6illustrates that the flared portion430is a countersink hole430a.

At750, one or more machining tools950may machine a counter bore410afrom the outer surface to form the first portion410.FIG. 5illustrates that the first portion410is a counter bore410a.

While the above description has described the flow process ofFIG. 5in a particular order, it should be appreciated that unless otherwise specifically required in the attached claims that the ordering of the steps may be varied and the order of the steps may occur simultaneously or near simultaneously, such as in layers.

Technical effects and benefits of the features described herein include a swing bed comprising a flared passageway to aid entrance of amine-based sorbent beads in an interior chamber and egression of the amine-based sorbent beads from the interior chamber.