Liquid film producing process and apparatus for fluid-liquid contacting

• US 5,535,989 A
• Filed: 12/02/1994
• Issued: 07/16/1996
• Est. Priority Date: 12/02/1994
• Status: Expired due to Fees

• Current Assignee: Dipak K. Sen
• Original Assignee: Dipak K. Sen
• Inventors: Sen, Dipak K.
• Primary Examiner(s): MILES, TIM
• Application Number:
  US08/323,914
• Time in Patent Office: 592 Days
• Field of Search: 261/112.1, 261/114.1, 55/240
• US Class Current: 261/112.1
• CPC Class Codes: B01D 3/008 Liquid distribution
• CPC Class Codes: B01D 3/20 Bubble caps; Risers for vapour; Discharge pipes for liquid
• CPC Class Codes: B01D 53/78 with gas-liquid contact
• CPC Class Codes: B01J 10/02 of the thin-film type
• CPC Class Codes: B01J 19/32 Packing elements in the form of grids or built-up elements for forming a unit or module inside the apparatus for mass or heat transfer
• CPC Class Codes: F28C 3/06 the heat-exchange media being a liquid and a gas or vapour temperators for cooling steam F22

Abstract

Processess and apparatus are provided to generate and use continuous and controlled liquid film for industrial and commercial applications requiring fluid-liquid contacts. In one version, a housing has a bottom and a tray mounted therein. The tray separates an upper section for holding liquid from a lower section for liquid-fluid interaction. Uniformly spaced, thin, straight film guides in close proximity extend downwardly from the tray towards the bottom. A narrow slit is formed in the tray along each line of film guides for enabling liquid in the upper section to flow to the lower section in the form of a flowing liquid curtain. The fluid can be a gas entering and exiting the housing through ports provided therein. In a preferred embodiment, a vertically extending tubular member is mounted centrally within several closed loops of film guides and extends through the tray. An adjustable sleeve is mounted on top of the tubular member and the tops of the film guides are secured to this sleeve. The invention may be used in a liquid-gas contacting column that comprises an upright vessel with a liquid inlet at the top and liquid outlet in a bottom portion. A series of trays are mounted one above the other in the vessel.

Claims

1. A fluid-liquid contacting apparatus comprising:

a housing having a bottom and a tray mounted therein, said tray separating an upper section of the housing for holding liquid and an enclosed lower section for liquid-fluid interaction; and

at least one line of substantially uniformly spaced, thin, straight film guides in close proximity extending downwardly from said tray towards said bottom, thereby defining a grille for establishing a flowing liquid film across a substantial section of said lower section, the liquid flowing in panes between adjacent film guides during use of the apparatus;

a fluid inlet at one side of said lower section of the housing and fluid outlet at an opposite side of said lower section; and

means for causing a fluid to flow across said lower section from said fluid inlet through said grille and said panes of flowing liquid, and to said fluid outlet;

wherein a narrow slit is formed in said tray along said at least one line of film guides for enabling liquid in the upper section to flow to the lower section and form said panes, whereby said fluid flowing through the lower section can efficiently interact with said liquid film during use of said apparatus by flowing through said liquid film.

2. A gas-liquid contacting apparatus comprising:

a housing compartmentalized by a tray mounted therein into an upper zone for holding a liquid and an enclosed lower zone for liquid-gas interaction;

said tray having at least one narrow slit therein for enabling liquid contained in the upper zone to flow to the lower zone; and

at least one line of substantially uniformly spaced, elongate, thin film guides mounted in close proximity in the housing and extending from said at least one slit in the tray and substantially into and across the interaction zone, thereby defining a grille for establishing a flowing film of liquid over a substantial area in the interaction zone, said film guides being arranged in sufficient proximity to one another that said liquid is able to flow in panes between adjacent guides;

at least one gas inlet or in said housing on one side of said grille;

at least one gas outlet port in said housing on an opposite side of said grille; and

motive means for causing said gas to flow through said grill and through said panes of flowing liquid, whereby said gas can interact with the liquid of said film.

3. The apparatus according to claim 2 wherein said film guides are formed from one or more strings or wires.

4. The apparatus according to claim 3 wherein said film guides are connected to a bottom of said housing and connected to said tray.

5. A gas-liquid contacting apparatus comprising:

a housing compartmentalized by a tray mounted therein into an upper zone for holding a liquid and a lower zone or liquid-gas interaction;

said tray having at least one narrow slit therein for enabling liquid contained in the upper zone to flow to the lower zone; and

at least one line of substantially uniformly spaced, elongate, thin film guides mounted in close proximity in the housing and extending from said at least one slit in the tray and substantially into the interaction zone, thereby defining a grille for establishing a flowing film of liquid over a substantial area of the interaction zone, said film guides being arranged in sufficient proximity to one another that said liquid is able to flow in panes between adjacent guides,

a vertically extending tubular member mounted centrally within said at least one line of film guides and extending through said tray, said at least one line forming a closed loop,

whereby a gas present in said interaction zone can interact with the liquid of said film.

6. The apparatus according to claim 5 including motive means for causing said gas to flow through said interaction zone.

7. The apparatus according to claim 6 including means for re-circulating liquid accumulating in said interaction zone to said upper zone.

8. The apparatus according to claim 5 wherein

said tubular member is hollow and elongate, has slots in the body thereof for flow of gas into or out of said tubular member, and has a height above said tray sufficient to clear the depth of liquid in said upper zone;

a plate is mounted to a bottom end of the tubular member to which bottom ends of said film guides are secured; and

an annular sleeve is slidably mounted on an upper portion of the tubular member and has at least one outwardly extending flange for adjusting the tension of said film guides which pass through said at least one slit in said tray and are secured to the flange.

9. The apparatus according to claim 8 wherein said at least one slit in said tray is a closed loop.

10. The apparatus according to claim 8 wherein there are a plurality of closed loops of film guides arranged concentrically, and said tray is divided into annular disks by concentric closed loop slits, said apparatus including means for connecting said annular disks.

11. The apparatus according to claim 10 including at least one screen surrounding said film guides for the protection thereof.

12. A liquid-fluid contacting apparatus comprising:

a vessel having at least one liquid inlet in a top portion thereof and at least one liquid outlet in a bottom portion thereof, said vessel also having at least one gas inlet and at least one outlet for a gas or vapour;

a series of trays each mounted horizontally and adapted to hold a body of liquid thereon;

at least one module mounted on each tray with each module comprising at least one line of substantially uniformly spaced, elongate, thin film guides mounted in close proximity and extending from at least one slit formed in the plane of the respective tray by the module and substantially into a liquid-fluid interaction zone below the respective tray, said film guides defining a grille for establishing a flowing film of liquid over an area in the interaction zone, said at least one module and said film guides being constructed and arranged so as to cause said gas or vapour passing through said interaction zone from said at least one gas inlet to said at least one gas outlet to flow through said grille and through said flowing film of liquid;

wherein in use of the apparatus, liquid entering through said at least one liquid inlet flows from each tray downwards to said bottom portion of the vessel by passing through one or more modules and gas or vapour passing through said interaction zone interacts with the liquid films formed by said modules.

13. A liquid-fluid contacting apparatus according to claim 12 wherein said apparatus is a column, said vessel is an upright, vertically extending vessel, and said trays are mounted one above the other in said vessel, and wherein in use of the column, the liquid flows downwards from the top tray to the bottom tray by passing through the slits formed by said modules.

14. A process for contacting a liquid with a gas or vapour for interaction therebetween, said process comprising:

providing a housing with a tray mounted therein, said tray separating said housing into an upper section and a lower section for liquid-gas or liquid vapour interaction;

delivering said liquid to said upper section;

delivering said as or vapour through a gas inlet into said lower section;

permitting said liquid to flow from the tray in the form of a liquid film down a line of thin, straight film guides positioned in close proximity to but spaced apart from one another, said film guides extending downwardly from said tray and into said lower section, said liquid covering the film guides and flowing in panes extending between adjacent film guides; and

passing said gas or vapour through said film guides and through said liquid film for a desired interaction between said liquid and said gas or vapour.

15. A process according to claim 14 wherein the liquid flows to a bottom of said housing, said process including reusing the liquid at the bottom of said housing by delivering the used liquid at the bottom of said housing to said upper section.

16. A process according to claim 14 wherein there are a number of narrow slits formed in said tray and said liquid is permitted to flow from said slits in the form of a number of separate liquid films down lines of thin, straight film guides.

17. A process according to claim 14 wherein said upper section is adapted to hold said liquid at least temporarily and said tray is formed with at least one narrow slit through which said liquid flows in the form of said liquid film, and wherein said film guides extend downwardly from the location of said slit.