Coalescer filter and method

Abstract

A coalescer filter is illustrated for removing material from a gas wherein a collection of liquid coalesced by passing a gaseous stream upwardly within a coalescing material packed in an upright cylindrical housing is facilitated by creating a pressure drop in a tube by venturi action in an inlet air stream and communicating the pressure drop to a canister. The use of a float valve is also illustrated for controlling the discharge of liquid collected in a sealed drainage canister receiving coalesced liquid from a lower portion of an upright column or housing containing coalescing material through which a gaseous stream is passed upwardly.

Description

The inlet orifice C, the inlet connection 12 and bore 12a form an inlet conduit through which an inlet gas or air stream flows.

By thus directing the gas from which material is to be coalesced upwardly in a stream within the coaleating material packed in the column, the stream expands and as a fountain and the coalesced material is separated and flows downwardly by gravity. Thus, coalescence takes place by directing the gaseous stream through the coalescing material upwardly against the force of gravity.

The expanded flow of the gaseous stream passes through the openings 10a and 10b and through the openings 10c and 10d into a downward flow extending across the filter column 19. The upward gaseous stream in the column A is centrally disposed or located in that it is preferably sufficiently spaced from the wall of the column A at least initially to permit coalescence with downward flow of separated material against the upward flow of the gaseous stream to permit upward coalescence with a downward flow of separated material als against the upwardflow of the gaseous stream.

The flow of coalesced liquid material through the drainage opening D is aided by producing a pressure differential between the upper opening D and the canister E into which the coalesced material flows. This is accomplished by the provision of a tube F which may be centrally disposed within the air stream flowing into the inlet orifice C on one end. This is illustrated as being accomplished within the bore or duct 12a within the base, but such may extend into the orifice C so long as a pressure differential is achieved. The important point is that one end of the tube is in a concentrated air flow or stream to create a pressure drop which is transferred to a canister for collecting the liquid coalesced material. The other end of the tube F is disposed in the canister E transferring the pressure differential therein.

Preferably the float valve G is used in combination with the tube F as described above. The float valve is preferably of the type schematically illustrated in FIGS. 3 and 4 and may be of a type supplied by Parker Hannifin Corporation, Otsego, Mich. 49078, and designated "automatic filter drain." The automatic filter drain G is positioned in the bottom of the canister E and includes a diaphragm 24 which is responsive to differential pressures created by the level of liquid in the canister across said diaphragm, ejecting liquids in the canister from same to air passage 25 permitting liquid to be drained through the threaded drain 26 which is threaded to accept, if required, a drain line, for the positively ejected liquids. The diaphragm 24 and the air passage 25 are contained in the housing 27 which is internally vented to the atmosphere and which is positioned by the nut 28 at the bottom of the canister.

In the absence of liquid the diaphragm 24 is seated closing the air passage 25. In view of the negative pressure gradient transferred by the tube F to the canister, flow of the coalesced liquid materials through the passage D to the canister is increased. The discharge is positively accomplished by means of the automatic filter drain positioned at the bottom of the canister E.

Thus, the collection of the coalesced liquid with solid impurities is facilitated by the provision of the canister which receives the liquid from the drainage passage D. In view of the negative pressure gradient created by the tube F to the canister, flow of liquid through the passage D to the canister is increased. The discharge is positively accomplished by means of the automatic filter drain positioned in the bottom of the canister E. The particular float valve described and illustrated is especially efficient and is preferred, although any float valve which operates efficiently as an automatic drain responsive to liquid level may be utilized. Other drain valves such as automatic float drains, cycle drains, or, electrically or pneumatically timed drain valves may be employed.

While a preferred embodiment of the invention has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.

Claims

1. A coalescer filter for removing a liquid from a gas comprising:

an upright housing;

coalescing material packed in said housing

an inlet conduit for gas through which an unfiltered gaseous stream enters a lower portion of said upright housing and is directed upwardly into said coalescing material;

a drainage opening positioned laterally of said inlet conduit receiving liquid coalesced in said housing;

a canister below said inlet conduit for collecting said liquid from said drainage opening; and

a tube extending upwardly from said canister into said gaseous stream in said inlet conduit creating a pressure drop in said tube differential between said drainage opening and said canister;

whereby a negative pressure gradient is created in said canister facilitating a flow of liquid into said canister.

2. The structure set forth in claim 1 including a drain in said canister for controlling discharge of liquid therefrom.

3. The structure set forth in claim 2 wherein said drain includes a float valve.

4. A coalescer air filter comprising

an upright cylindrical housing containing coalescing: material;

an air inlet conduit through which an unfiltered air stream enters a central lower portion of said upright housing and is directed upwardly into said coalescing material;

a drainage opening positioned laterally of said air inlet conduit receiving liquid coalesced in said housing;

a canister below said air inlet conduit for collecting said liquid from said drainage opening; and

an air tube extending upwardly from said canister into said air stream in said inlet conduit;

whereby a pressure drop in said air tube differential between said drainage opening and said canister caused by said air flow stream facilitates a flow of liquid into said canister by reducing air pressure in said canister.

5. A coalescer air filter comprising:

an upright cylindrical housing containing coalescing material packed therein;

an air inlet conduit through which an unfiltered air stream enters a lower portion of said upright housing and is directed upwardly into said coalescing material;

a drainage opening positioned laterally of said air inlet conduit receiving liquid coalesced in said housing;

a canister for collecting said liquid from said drainage opening;

a tube extending from said canister into said air stream in said inlet conduit; and

a float valve in said canister controlling the discharge of liquid collected in said canister;

whereby a pressure drop in said tube differential between said drainage opening and said canister caused by said air stream facilitates a flow of liquid into said canister by reducing air pressure in said canister.

6. The structure set forth in claim 5 including an upright housing containing a filter carried in side by side relation with said first mentioned upright housing receiving air from an upper portion of said first mentioned housing for downward movement through said filter.

7. The method of removing liquids from an air stream comprising the steps of:

providing an upright cylindrical housing containing coalescing material:

forming an air stream in said cylindrical housing upwardly through said coalescing material;

causing said liquids contained within said air stream to coalesce and flow downwardly by gravity in a direction opposite to the upward flow of said gaseous stream; and

causing a pressure drop in a canister receiving coalesced liquids by positioning a tube having one end in said canister and the other end in said air stream to create a pressure drop in said canister.

8. The method of removing liquids from air comprising the steps of:

forming an air stream;

providing an upright cylindrical housing containing coalescing material;

introducing air to said cylindrical housing through said coalecing material;

causing liquids contained within said air to coalesce and flow downwardly; and

causing a pressure drop in a canister positioned below said housing receiving coalescend liquids by positioning a tube having one end in said canister and the other end in said air stream to create a pressure drop in said canister.

9. The method set forth in claim 8 11 including the step of utilizing a float drain in said canister to drain coalesced liquid therefrom.

10. The method set forth in claim 8 11 including the step of positively expelling coalesced contaminants from said canister utilizing an automatic filter drain in a bottom of said canister.

11. The method of removing liquids from air comprising the steps of:

forming an inlet air stream;

providing an upright cylindrical housing containing coalescing material;

introducing said inlet air stream to said cylindrical housing through an inlet air conduit and thence upwardly through said coalescing material;

causing liquids contained within said air to coalesce and flow downwardly;

causing a pressure drop in a canister positioned below said housing receiving coalesced liquids by positioning a tube having one end in said canister and the other end in said inlet air stream in said conduit prior to passage through said coalescing material to create a pressure drop in said canister;

draining said liquids from a lower portion of said housing through an opening spaced laterally of said inlet air conduit with the aid of said pressure drop in the canister.