Apparatus and process for equilibrating gas and liquid

• US 4,600,697 A
• Filed: 06/17/1976
• Issued: 07/15/1986
• Est. Priority Date: 06/17/1976
• Status: Expired due to Term

• Current Assignee: Fahad M. Al-Athel
• Original Assignee: Analytical Products Incorporated
• Inventors: Smernoff, Ronald B.
• Primary Examiner(s): Marcus, Michael S.
• Application Number:
  US05/697,269
• Time in Patent Office: 3,680 Days
• Field of Search: 23/259, 23/253 R, 23/232 R, 23/254 R, 23/230 B, 23/258.5, 55/68, 422/50, 422/68, 422/81, 422/99, 422/101, 422/44, 436/11, 436/68, 436/174, 436/178, 261/82
• US Class Current: 436/174
• CPC Class Codes: G01N 33/0006 Calibrating gas analysers
• CPC Class Codes: Y10T 436/102499 Blood gas standard or control
• CPC Class Codes: Y10T 436/205831 Carbon monoxide only
• CPC Class Codes: Y10T 436/209163 Dissolved or trace oxygen or oxygen content of a sealed environment
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

The invention is concerned with apparatus for equilibrating an aqueous solution with gas. The apparatus includes a gas vessel having therewithin a gas of a selectable composition at a pressure above ambient atmospheric pressure. Flow control means receive flow from the vessel and control a flow rate therefrom. A solution tube is provided having an aqueous solution therewithin. Conduit means lead from the flow control means to the tube below a liquid level of the aqueous solution. Means are also provided for causing the gas to be delivered within the aqueous solution below the liquid level as a plurality of bubbles. The process of the present invention is directed at simultaneously equilibrating a plurality of aqueous solutions each with one of a plurality of gas compositions. The process comprises positioning a plurality of solutions tubes, each having an open end and a closed end, in mating fit within a respective one of a plurality of cavities formed within a heat conductive block with the open ends of the tubes upwardly and a respective one of a plurality of aqueous solutions in each of the tubes. The temperature of each of the solutions is adjusted to be substantially equal by controlling the temperature of the block to a desired value. A respective one of the plurality of gas compositions is delivered below a respective liquid level of a respective aqueous solution within each respective one of the tubes in the form of bubbles.

Claims

1. Apparatus for equilibrating a hydrophilic liquid such as an aqueous solution with a gas, comprising:

a gas vessel having therewithin a gas of a selectable composition at a pressure above ambient atmospheric pressure;

flow control means receiving flow from said vessel and controlling a flow rate therefrom;

a removable solution tube having a hydrophilic liquid therewithin;

a heat conductive block having a cavity therewithin sealingly matingly holding said removable tube therewithin;

conduit means leading from said flow control means to said tube below a liquid level of said hydrophilic liquid; and

means for causing said gas to be delivered within said hydrophilic liquid below said liquid level as a plurality of bubbles.

2. Apparatus as in claim 1, wherein said bubble delivery means comprises a porous member having a hydrophobic surface forming a bottom of said tube, said member being impervious to flow of said liquid therethrough when said tube if filled therewith and being permeable to flow of said gas composition upwardly therethrough.

3. Apparatus as in claim 2, including:

means for adjusting the temperature of said block and thereby the temperature of said tube and said liquid.

4. Apparatus as in claim 3, including:

means for equilibrating the temperature of said gas with the temperature of said block.

5. Apparatus as in claim 4, including:

means for measuring the temperature of said block.

6. Apparatus as in claim 3, wherein said cavity sealingly matingly removably holds said tube via compressible sealing means which seal said cavity to an exterior of said tube and provide a compression force to hold said tube within said cavity.

7. Apparatus as in claim 2, including, intermediate said vessel and said flow control means:

pressure regulator means for regulating a pressure of said gas exiting therefrom to a selected valve.

8. Apparatus for simultaneously equilibrating a plurality of hydrophilic liquids such as aqueous solutions with a plurality of gas compositions, comprising:

a plurality of gas vessels each having therewithin a gas of a particular composition at a pressure above atmospheric pressure;

a plurality of flow control means, one for receiving flow from each of said vessels and controlling the flow rate therefrom;

a plurality of removable solution tubes, each holding a hydrophilic liquid therewithin;

a heat conductive block having a plurality of cavities therewithin, each sealingly matingly holding a respective one of said tubes removably therewithin;

a plurality of conduit means, one leading from each respective one of said tubes below a respective liquid level of the liquid therewithin; and

a plurality of means for causing said gas to be delivered as bubbles within each respective liquid below a respective liquid level thereof.

9. Apparatus as in claim 8, including:

means for adjusting the temperature of said block and thereby the temperature of said tubes and said liquids.

10. Apparatus as in claim 9, including:

means for equilibrating the temperature of each of said gases with the temperature of said block.

11. Apparatus as in claim 10, including:

means for measuring the temperature of said block.

12. Apparatus as in claim 10, wherein said bubble delivery means each comprise a porous member having a hydrophobic surface forming a bottom of a respective one of said tubes, said members being impervious to flow of said liquid therethrough when said tubes are filled therewith and being permeable to flow of said gases upwardly therethrough.

13. Apparatus as in claim 12, wherein said cavities sealingly matingly removably hold said tubes via a plurality of compressible sealing means each sealing a respective one of said cavities to an exterior of a respective one of said tubes and providing a compression force to hold said respective one of said tubes within said respective one of said cavities.

14. Apparatus as in claim 10, including:

a plurality of pressure regulator means, one intermediate each respective one of said vessels and a respective one of said flow control means, for regulating a pressure of a respective one of said gases exiting said respective pressure regulator means to a selected value.

15. In an apparatus for equilibrating an aqueous solution with a gas composition which comprises a gas vessel having therewithin a gas of a selectable composition at a pressure above ambient atmospheric pressure, flow control means for receiving flow from said vessel and controlling a flow rate therefrom and a removable solution tube having an aqueous solution therewithin, an improvement which provides extremely fast attainment of gas-solution equilibrium, comprising:

a heat conductive block having a cavity therewithin sealingly matingly holding said tube removably therewithin;

conduit means leading from said flow control means to said tube below a liquid level of said aqueous solution; and

means for causing said gas composition to be delivered within said aqueous solution below said liquid level as a plurality of bubbles.

16. An improved apparatus as in claim 15, wherein said bubble delivery means comprises a porous member having a hydrophobic surface forming a bottom of said tube, said member being impervious to flow of said solution therethrough when said tube is filled therewith and being permeable to flow of said gas composition upwardly therethrough.

17. An improved apparatus as in claim 16, including:

means for adjusting the temperature of said block and thereby the temperature of said tube and said solution.

18. An improved apparatus as in claim 17, including:

means for equilibrating the temperature of said gas with the temperature of said block.

19. An improved apparatus as in claim 18, including:

means for measuring the temperature of said block.

20. An improved apparatus as in claim 16, wherein said cavity sealingly matingly removably holds said tube via compressible sealing means which seal said cavity to an exterior of said tube and provide a compression force to hold said tube within said cavity.

21. An improved apparatus as in claim 20, including, intermediate said vessel and said flow control means:

pressure regulator means for regulating a pressure of said gas exiting therefrom to a selected valve.

22. A process for simultaneously equilibrating a plurality of aqueous solutions each with one of a plurality of gas compositions, comprising:

positioning a plurality of solution tubes each having an open end and a closed end in sealing mating fit within a respective one of a plurality of cavities formed within a heat conductive block with the open end thereof upwardly and a respective one of a plurality of aqueous solutions in each of said tubes;

adjusting the temperature of said solutions to be substantially equal by controlling the temperature of said block to a desired value; and

delivering a respective one of said plurality of gas compositions below a respective liquid level of a respective aqueous solution within each respective one of said tubes in the form of bubbles.

23. A process as in claim 22, wherein said tubes each include closing the closed end thereof of a porous member having a hydrophobic surface to prevent flow of said respective aqueous solution therethrough and said delivery step comprises introducing a respective one of said plurality of gas compositions against a bottom side of each respective one of said cavities at a sufficient pressure to force said respective one of said compositions to flow through said respective one of said members and form a plurality of bubbles within each respective one of said tubes adjacent a respective closed end thereof.