US2485038A

US2485038A - Apparatus for washing and cooling gases

Info

Publication number: US2485038A
Application number: US608907A
Authority: US
Inventors: Culkosky Martin
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-08-04
Filing date: 1945-08-04
Publication date: 1949-10-18
Anticipated expiration: 1966-10-18

Description

0m. 18, 1%49 QULKOSKY APPARATUS FOR WASHING AND COOLING GASES 2 Sheets-Sheet 2 Filed Aug. 4, 1945 Patented Oct. 18, 1949 APPARATUS FOR WASHING AND COOLING GASES Martin Culkosky, Gary, Ind.

Application August 4, 1945, Serial No. 608,907

3 Claims. (Cl. 261-11) This invention relates to an apparatus for washing and cooling gas, particularly compressed gas as it leaves the compressor.

An object of the invention is the provision of cheap, easily made and maintained apparatus for removing oil, dust, and other foreign materials from compressed gas and for cooling the gas so as to insure gas free from excess moisture during its travel to the point at which it is used.

This and other objects of the invention will be more fully apparent in the following description.

In installation in which gases are compressed, for instance compressed air systems, considerable trouble has been encountered due to foreign materials in the compressed gas, such as dust particles, entrained moisture. and oil which may be introduced into the gas by the compressor. In an attempt to eliminate the first two of such materials from the compressed gas there have been used air filters and moisture eliminators which have been installed in the air intake between the atmosphere and the air compressor. Such devices, however, obviously do not eliminate the oil which may be introduced into the air by the compressor, nor do they, eliminate the excess moisture in the compressed air caused by its reduction in volume and elevation'in temperature due to compression and its cooling in the main on the way to its point of use. As a result of such heating and subsequent cooling in the main, excess moisture in such prior installations has been deposited in the main and branch distributing pipes and has caused dimculty in the apparatus in which the compressed air is used.

The present invention provides a simple apparatus whereby compressed gases, particularly at a point immediately following the compressor,

may be substantially freed from such foreign materials as dust, oil, and excess moisture, and may be cooled to such a temperature and have its moisture content so adjusted that the gas will be saturated with moisture at the pressure and temperatureat which it is distributed and used.

The invention will be more readily understood by reference to the accompanying drawings, in

Figure 3 is a view in vertical cross section through such gas washer and cooler, the section being taken along the line III1'J1 in Figure 2;

Figure 4 is a view in a horizontal cross section through the apparatus shown in Figure 3, the section being taken along line IV-IV of that figure; and

Figure 5 is a view in vertical cross section through the-trap connected to the gas washer and cooler for the elimination of the foam and excess water from the cooling water bath thereof.

In the apparatus shown in Figure 1 the gas compressing, washing, cooling, distributing, and utilizing system consists generally of a gas compressor 3 which may be of any known type, such as a rotary or reciprocating compressor, which feeds the compressed gas through the pipe 6 into the gas washing and cooling apparatus generally designated by the reference character I. From such washing and cooling apparatus the gas now cleaned and cooled and with its moisture content adjusted as above described, is led through pipe 26 into the compressed gas distributing main 1 from which it may be taken at various desired points, as by a branch pipe 9 tapped thereinto, to the various pieces of apparatus employing compressed gas, of which in the case of compressed air the air driven abrading device II is typical. The air compressor 3 is shown provided with a filter 5 between the intake and the atmosphere; it is preferred that such be employed to minimize wear on the compressor by dust particles in the air and to reduce the amount of impurities to be removed by the air washer and cooler. It is possible, however, by use of such air washer and cooler l as shown to dispense, if desired, with the intake filter on the compressor.

The gas washer and cooler l consists of a fluid tight tank 2, which is shown of generally cylindrical shape, having a central axially directed right circular cylindrical downcomer 4 projecting through the top thereof, said downcomer being closed at the top but being open at the bottom at a point well below the top of the bath of liquid gas washing and cooling medium maintained in the tank. The compressed air inlet pipe 6 leads into the top of the downcomer, as shown in Figures 1 and 3, and is provided on its inner end with a nozzle 8 directed downwardly and generally tangentially to the inner surface of the downcomer, as shown in Figures 2 and 3. A further pipe [0, for the introduction of purging steam when the apparatus is to be cleaned, leads into the top of the downcomer at a point opposite to that at which pipe 6 enters, pipe l being provided on its inner end within the downcomer with a nozzle 12 likewise directed downwardly and tangentially of the inner surface of the downcomer. During normal use of the apparatus in washing and cooling gas steam is not admitted through pipe I and nozzle H, the shut-01f in pipe l0 being closed.

The lower open end of the downcomer is positioned axially of the tank by means of a periorated plate l4 extending transversely of the axis of the tank. Plate l4 may be positioned and secured as by being welded to the downcomer, the tank, or both. In its normal operative condition the tank is provided with a bath of not be renewed until the next cooler and washer cleaning operation. Such bath may be intro-- duced as by removing the plug in top hole 34 and connecting a liquid supply pipe such as a hose thereto. The provision of a plurality of openings 34 makes possible the employment of different levels of the liquid bath in the tank to insure eincient operation under varying conditions, such as varying pressures to which the gas is compressed.

The gas washer and cooler of the present invention thus far described functions as follows:

cooling liquid, as for instance water, which when the apparatus operates as shown extends to the height of the line IE within the tank outside the downcomer but i depressed to a level H3, in the same horizontal plane as the lower edge of the downcomer, due to the pressure of the incoming compressed gas. Such gas after traveling downwardly through the downcomer, escapes from the lower end of the downcomer and then passes upwardly through the perforations in plate l4 into the space within the tank outside the downcomer and above the liquid bath whence it is led to the compressed gas main by pipe 26. The inner end of the pipe 26 extends inwardly some distance from the inner wall of the tank to prevent the condensate which flows down the inner wall of the tank from entering the pipe. Positioned below plate 14 is a cooling coil supplied with refrigerant by inlet and outlet pipes 22 and 24, respectively, so that the washing and cooling bath may be maintained at a constant temperature. Some means of cooling the bath, such as the cooling coil shown, is necessary if the apparatus is to be operated for any appreciable time, since the gas leaving the compressor is at a temperature well above normal atmospheric temperature due to its compression.

A further steam pipe is led to the bottom of the tank at a point immediately above plate l4, pipe 30 being provided at its inner end with a nozzle 32 directed downwardly and tangentially of the wall of the tank as shown in Figures 3 and 4. The shut-off shown in pipe 30, as is that in pipe l0 above described, is normally closed, purging steam being introduced within the tank only during the infrequent periods in which the liquid bath is removed and the tank is cleaned. When the tank is cleaned the shut-off in blow-off pipe 28 at the bottom of the tank is opened to run the liquid bath out of the tank and to allow the exhaust of sludge and steam during the purging operation.

Along one side of the tank there is provided a series of openings 34 lying vertically one above the other. During normal operation of the apparatus but two of the openings are used, the others being closed by plugs screwed thereinto. In the lower of the openings utilized there is screwed a pipe 38 leading to the foam and excess water eliminating trap 40, and in the opening thereabove there is screwed the water level determining pipe 36. Trap 40, which will be more fully described hereinafter, functions to maintain the level I 6 of the bath constant as well as to remove foam from the top of the bath. It is preferred,- however, occasionally to try the level of the bath by opening the shut-off in pipe 36 to make sure the water level has not risen too high for emcient operation. When once introduced and brought to the proper height, the liquid bath need The gas, heated by reason of its compression, and containing entrained moisture, oil, and some dust particles, enters the downcomer through the .nozzle 8 in the direction shown by the arrows. By

reason of the direction of nozzle 8 tangential to the wall of the downcomer the gas, traveling at high velocity, impinges at a substantial angle upon the wall of the downcomer, thereby tending to deposit entrained particles of solid matter as well as .oil and water on the inner surface of the downcomer. The oil and water then trickle down into the washing and cooling bath, carrying with it any deposited solid particles. The gas then continues its travel down the downcomer in a spiral direction until it emerges from the lower end of the downcomer and enters the liquid bath. The gas then travels upwardly at a greatly reduced velocity through theperforated plate l4. The plate l4 causes the air to be divided into a plurality of fine streams and bubbles and consequently to be intimately contacted by the liquid bath so that it is efficiently cooled and thoroughly cleaned. In the preferred mode of operation of the device the cooling coils 20 are kept to such temperature relative to the volume of the liquid bath and of the gas traveling therethrough that the gas entering pipe 26 is at a temperature equal to the coldest temperature encountered by it in its travel to its point of application; the gas entering pipe 26 will obviously be at or near saturation, due to its travel through and intimate contact with the cooling liquid. Consequently in its travel through the gas main 1, the branch pipe 9, and in the gas utilizing apparatus such gas does not deposit moisture.

The solid particles removed from the compressed gas, as well as the oil and water removed therefrom, pass down the inner surface of the downcomer and into the washing and cooling liquid bath. To remove the excess water so added to the bath, and thus to keep the bath level constant, as well as to remove the oil, which forms a foam on top of the bath, and such solid particles as are caught therein rather than settling through the bath to form a sludge, there is employed the trap 40. Various known commercially available water traps may be employed for trap 40 in the system shown. A typical water trap which has proved satisfactory is the bucket type trap which is shown in Figure 5. Such trap consists of an upper portion 44 to which is connected the inlet pipe 38 from the tank 2 and an outlet pipe 42, part 44 forming a. cap for the bottom cup portion 46 of the trap, to which bottom cup portion it is sealed as by a gasket. Part 44 is provided with a downwardly extending central hollow stem 48 along which is guided for axial movement the vertically movable bucket 50. Radially directed struts 52 attached to the inner surface of the bucket serve to center the bucket relatively of the stem and to guide it for travel .therealong. The bottom of the bucket is provided with an inwardly directed adjustable valve needie 54 cooperating with the conical opening 56 in the lower end of the hollow stem 48, so that when the bucket is raised the valve needle closes the passage through the stem and when the bucket is lowered such passage, which leads from the interior of the bucket to the outlet pipe 42, is open. It will be apparent that when the uplift on the bucket from water on the outside thereof exceeds the weight of the bucket and the materiaLwithin it, the bucket will rise and will close the valve, and that when the weight of the bucket and the material within it exceeds the uplift, the bucket will sink and open the valve.

Condensate from the air, oil, and foam flowing through pipe 38 .will' overflow over the upper edge of the bucket, the water being on the bottom and the oil and foam floating on the top. When suflicient water, oil, and foam have gathered within the bucket so that its weight overcomes the uplift on the bucket, the bucket moves downwardly, opening the valve in the hollow stem and allowing first the water in the bucket and then the oil and foam to be forced by the air pressure within tank 2 and consequently in pipe 38, out the stem to the exhaust pipe. When the material in the bucket has become exhausted sufficiently, however, the uplift on the bucket again exceeds its weight and the valve closes. Such operation, continuously repeated, maintains the level 16 0f the liquid bath within the tank constant and insures the constant removal of the oil and foam which forms on top of such bath.

Having thus fully illustrated and described preferred embodiments of the apparatus of my invention, I desire to claim as new the following:

1. Apparatus for washing and cooling compressed gas which comprises a closed tank having a liquid washing and cooling bath in the bottom thereof, a cylindrical downcomer closed at the top and having an open bottom extending into the bath, means to introduce compressed gas into the top of the downcomer so that it impinges at a substantial angle on a sidewall of the downcomer and travels downwardly thereof, said means comprising a nozzle extending through the wall of the downcomer and directed generally tangentially of the inner wall of the downcomer and downwardly with respect thereto, whereby the compressed gas after impingement on the sidewall travels downwardly in a spiral path through the downcomer and then upwardly through the bath outside the downcomer, a perforated plate around the bottom of the downcomer and below the top of the liquid bath in the tank so that the gas is divided into fine streams in its passage through such bath, means to collect the washed gas above the bath in the tank for delivery to a compressed gas using instrumentality. and means for cooling the liquid bath to maintain it at a predetermined temperature, whereby the moisture content of the washed gas is adjusted to a point of substantial saturation at the lowest temperature it subsequently encounters.

2. Apparatus for washing and adjusting the moisture content of compressed gas which comprises a closed tank having a liquid washing bath in the bottom thereof, a cylindrical downcomer closed at the top and having an open bottom extending into the bath, means to introduce compressed gas into the top of the downcomer so that it impinges at a substantial angle on a, sidewall oi the downcomer and travels downwardly thereof, said means comprising a nozzle extending through the wall of the downcomer and directed generally tangentially of the inner wall of. the'downcomer and downwardly with respect thereto, whereby the compressed gas after impingement on the sidewall travels downwardly in a spiral path through the downcomer and then upwardly through the bath outside the downcomer, a perforated plate around the bottom of the downcomer and below the top of the liquid bath in the tank so that the gas is divided into fine streams in its passage through such bath, means to collect the washed gas above the bath in the tank for delivery to a compressed gas using instrumentality, and means for cooling the liquid bath to maintain it at a predetermined temperature, whereby the moisture content ofthe washed gas is adjusted to a point of substantial saturation at the lowest temperature it subsequently encounters, and means to maintain the level of the liquid bath in the tank substantially constant and to remove oil and foam from the top of such bath.

3. In the combination of a gas compressor and a compressed gas main leading therefrom, the improvement which comprises a device interposed in the line between the compressor and the gas main for washing and adjusting the moisture content of the compressed gas, said device comprising a closed tank having a liquid washing and cooling bath in the bottom thereof, a cylindrical downcomer closed at the top and having an open bottom extending into the bath, means to introduce compressed gas into the top of the downcomer so that it impinges at a substantial angle on a sidewall of the downcomer and travels downwardly thereof, said means comprising a nozzle extending through the wall of the downcomer and directed generally tangentially of the inner wall of the downcomer and downwardly with respect thereto, whereby the compressed gas after impingement on the sidewall travels downwardly in a spiral path through the downcomer and then upwardly through the bath outside the downcomer, a perforated plate around the bottom of the downcomer and below the top of the liquid bath in the tank so that the gas is divided into fine streams in its passage through such bath, means to collect the washed gas above the bath in the tank for delivery to a compressed gas using instrumentality, and means for cooling the liquid bath to maintain it at a predetermined temperature, whereby the moisture content of the washed gas is adjusted to a point of substantial saturation at the lowest temperature it subsequently encounters.

MARTIN CULKOSKY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS