US3327774A

US3327774A - Steam surface condenser

Info

Publication number: US3327774A
Application number: US463254A
Authority: US
Inventors: Leslie L Forster
Original assignee: Ingersoll Rand Co
Current assignee: Ingersoll Rand Co
Priority date: 1965-06-11
Filing date: 1965-06-11
Publication date: 1967-06-27
Anticipated expiration: 1984-06-27

Description

June 27, 19 7 L. L. FORSTER STEAM SURFACE CONDENSER 2 Sheets-Sheet 2 Filed June 11, 1965 INVENTOR. LESLIE L. FORSTER AGENT United States Patent 3,327,774 STEAM SURFACE CONDENSER Leslie L. Forster, Easton, Pa., assignor to Ingersoll-Rand Company, New York, N.Y., a corporation of New Jersey Filed June 11, 1965, Ser. No. 463,254 16 Claims. (Cl. 165-40) ABSTRACT OF THE DISCLOSURE Apparatus for use with a condenser for removing noncondensable elements from condensate. It includes a chamber separate from the condensate reservoir. Steam is introduced into the separate chamber for increasing the pressure in the chamber to drive off noncondensable elements and return them to the condenser inlet. There is apparatus for controlling the input of steam in response to conditions which indicate excess noncondensable elements.

This invention relates generally to steam surface, to condensers, and more particularly to apparatus for removing noncondensable elements from condensate which results in a more efiicient condenser operation.

Heretofore, during periods of light load and/or low condenser circulating water temperature, a satisfactory degree of processing for deaeration, degasification, and removal of other contaminates from the condensate from a steam surface condenser is very diflicult to obtain. Attempts to achieve satisfactory processing under such stringent conditions heretofore have led to the heating of all of the condensate in the condenser hot Well by injecting external steam directly into the condensate to raise the temperature of the condensate for removing therefrom the noncondensable elements. The foregoing has not always proven completely successful in producing a higher quality of cleansed condensate because some of the noncondensables remain on or near the surface of the condensate in the hot well and are not passed into the cooler for transmission to removal equipment. Thus, such noncondensa'bles are subject to reabsorption by the condensate in the hot well.

It is an object of the present invention to avoid and overcome the foregoing and other difiiculties of and objections to prior practices in association with steam surface condensers by positive venting or removal of noncondensable elements from steam when it is condensed to provide cleansed condensate.

Another object of the present invention is to eliminate the reabsorption of noncondensable elements by cooled portions of processed condensate.

Still another object of the present invention is to provide simple and efiicient deaerating processing apparatus for steam surface condensers for removal of noncondensable elements from condensate in an atmosphere nonconducive to reabsorption.

The present invention contemplates apparatus in association with a condenser having an inlet to receive steam, means for condensing such steam, means for removing noncondensables and for receiving condensate resulting from condensation; comprising chamber means for receiving condensate from the condensate receiving means of the condenser and having a discharge line for condensate, means for freeing noncondensable elements from the condensate in the chamber means and for creating pressure "ice in the chamber means in excess of pressure of the inlet steam flow of the condenser, and conduit means for passing freed noncondensables from the chamber means to the inlet steam flow of the condenser.

The foregoing and other objects and advantages Will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings wherein several embodiments of the invention are illustrated by way of example. It is to be expressly understood, however, that the drawings are for illustration purposes only and are not to be construed as defining the limits of the invention.

FIG. 1 is an end view, partly in section, diagrammatically illustrating the present invention embodied in a steam surface condenser;

FIG. 2 is a diagrammatic sectional view taken generally on line 2-2 of FIG. 1;

FIG. 3 is a view similar to FIG. 1 diagrammatically illustrating a modified embodiment of the invention and a modified control means thereof; and

FIG. 4 is a diagrammatic sectional view of the heating chamber of FIG. 1 and a further modified control means of the invention.

Although the present invention and the principles thereof are broadly applicable to liquid deaeration, in general, the present invention is particularly adapted for use in conjunction with condensers, within or without a condenser shell, hence, it has been so illustrated and will be so described.

Referring now to the drawings and particularly to FIGS. 1 and 2, a steam surface condenser 10 has an outer shell 12 and a standard tube bundle 14 which carries cooling water for condensing steam delivered to the condenser 10 at a steam inlet 16. Steam from inlet 16 flows longitudinally through the condenser 10 across the tube bundle 14 during which time it is condensed and the resulting condensate falls or drops into a reservoir or condenser hot well 18, while released noncondensable elements are discharged from condenser 10 by standard removal equipment 40 (not shown), well known in the art, having a discharge or take-off line 42. However, as hereinbefore described, some of the noncondensable elements are reabsorbed by condensate in hot well 18.

To effect a substantially complete removal of noncondensables from the condensate, a processing chamber 20 y is provided in or adjacent to hot well 18 and, as shown in FIG. 2, is in communication with hot well 18 through a water seal 22 formed by a wall open at the bottom between hot well 18 and chamber 20 to receive condensate therefrom. A pump 26 is connected to chamber 20 by condensate outlet or discharge line 24 to positively remove condensate from condenser 10. Condensate, therefore, flows from hot well 18 through seal or opening 22 into processing chamber 20 from whence it is discharged through the condensate outlet 24.

To further remove noncondensable elements while condensate is in the chamber 20, a medium, such as heating steam, is provided from an external source (not shown) by a line 28. The heating steam is injected or discharged from inlet line 28 directly into the condensate by suitable means, such as a spray, a perforated header, or a pipe coil and heats the condensate to its boiling temperature at the pressure existing in chamber 20' for releasing substantially all of the remaining noncondensable elements.

A conduit or duct 30 in communication with chamber 20 is provided to pass noncondensable elements released from condensate in chamber 20, such as air, together with attendant steam, into the steam flow from inlet 16, immediately above the tube bundle 14, and subject the noncondensable elements to the full influence of the removal equipment 40 which are effectively removed from the condenser through line 42.

T o automatically control injection of heating steam into chamber 20, control means for maximum efficiency may be provided but, is not essential to the practices of the present invention. One form of implementation of such control means is shown in FIGS. 1 and 2 wherein an orifice plate 32 is provided in duct 30 and a control assembly 34 has a flow control valve 38 connected in line 28 to control flow of heating steam to chamber 20. The control assembly 34 may be of a well-known type, having a pressure responsive element, for example, a diaphragm responsive to pressure drop across orifice 32 or to the pressure in chamber 20 for controlling by electrical, pneumatic or any other well known means, the automatic steam flow control valve 38 for controlling flow of heating steam to chamber 20. The automatic control assembly 34 has sensors on both sides of orifice 32 or in chamber 20 to sense pressure differential or pressure to which it responds with its valve 38 for controlling flow in line 28 to provide a desired quantity of heating steam, irrespective of condensate flow or temperature, to cause boiling of condensate in chamber 20 at a pressure slightly higher than the pressure present in steam inlet 16. Thus, condensate in chamber 20 is maintained at boiling temperature to release the noncondensa-ble elements, and sufficient pressure drop across orifice 32 or pressure in chamber 20 is maintained to assure positive flow of noncondensable elements and attendant steam into the steam flow from inlet '16.

It will now be understood that as the pressure drop across orifice 32 or the pressure in chamber 20 varies, the control assembly 34 will respond to such change and automatically adjust its control valve 38 to deliver more or less heating steam, as required, to chamber 20. Therefore, the flow of heated steam to chamber 20 is controlled by pressure drop across orifice 32 or pressure in chamber 20 irrespective of the rate of discharge flow of condensate or chamber temperature. Therefore, condensate discharged through condensate outlet 24 is substantially free from noncoudensables.

Although chamber 20 and duct 30 heretofore have been described as being enclosed within the shell of condenser 10, as shown in FIGS. 1 and 2, it should be understood that there may be times, such as modifying an existing condenser installation, when it is necessary or desirable to provide the novel apparatus externally or as an attachment to a condenser. To accomplish this, as shown in FIG. 3, adjacent walls of condenser 10 and chamber 20 have aligned openings in their bottoms to provide a Water seal 22A corresponding to seal 22 to provide a flow path for condensate from hot Well 18. Duct 30 now extends upwardly along the wall of condenser 10, extends therethrough immediately above tube bundle 14, and terminates in the same location as in FIG. 1.

Alternatively, it will be understood that flow in line 28 of external heating steam to chamber 20 can be controlled in response to changes in the condensate level in chamber 20, or changes in the difference between the levels of condensate in hot well 18 and chamber 20. Towards this end, as also shown in FIG. 3, a liquid level or liquid level diiferential responsive control assembly 34A, corresponding to assembly 34, automatically controls its valve 38A, corresponding to valve 38, connected in line 28. To provide the required signals, assembly 34A has a liquid level sensor in chamber 20 when responsive to changes of the level of liquid therein and a second such liquid level sensor in hot well 18 when responsive to changes in liquid level differential.

Further, alternatively, the flow of heating steam to chamber 20 can be directly controlled in response to the oxygen content of discharged condensate. As shown in FIG. 4, a control assembly or oxygen analyzer 34B is provided in condensate discharge line 24 and automatically operates its valve 38B, corresponding to valve 38.

It should be realized that practice of the present invention may be accomplished by the apparatus of either FIG. 1 or FIG. 3 in the absence of means for controlling the flow of heating steam or in conjunction with any of the control means shown in FIGS. 2 to 4. The rate of flow of heating steam for the novel apparatus in the absence of control means is determined by normal or mean operating conditions. i

It noW will be understood by those skilled in the art that the objects of the present invention have been achieved by providing means for freeing noncondensable elements from condensate, in an atmosphere noncondncive to reabsorption, with positive venting of such noncondensables to removal equipment to insure condensate substantially free from noncondensable elements.

Although several embodiments of the invention have been illustrated and described in detail, it is to be expressly understood that the invention is not limited thereto. Various changes may be made in the design and arrangement of the parts without departing from the spirit and scope of the invention as the same will now be understood by those skilled in the art.

I claim:

1. For use in combination with a condenser having a casing with inlet means for steam, means disposed within said casing below said inlet for condensing said steam and a reservoir for condensate, apparatus for removing noncondensable material from the condensate comprising:

a chamber means for receiving condensate from said reservoir and for processing said condensate to free noncondensable elements therefrom and having an outlet for releasing condensate from the condenser;

rneans providing a passage between the reservoir and the chamber for allowing condensate in the reservoir to pass into the chamber and providing a fluid seal between said reservoir and said chamber;

means operatively associated with the chamber for creating pressure in the chamber in excess of the pressure in the steam inlet to thereby maintain the level of condensate in the chamber below the level of condensate in the reservoir and for freeing noncondensable elements from condensate in the chamber;

means for regulating said means for creating pressure in the chamber in excess of the pressure in the steam inlet; and

duct means connecting the chamber to the condenser between the steam inlet and the condensing means for receiving noncondensable elements freed from the condensate in the chamber and releasing such elements into the condenser between said steam inlet and said condensing means.

2. Apparatus in accordance with claim 1, wherein:

the means for freeing noncondensable elements is an inlet line adapted to receive a heating medium, and extending into the chamber and condensate therein to discharge such heating medium into the condensate for causing the condensate to boil and release noncondensable elements therein.

3. Apparatus in accordance with claim 2, wherein:

the means for freeing noncondensable elements includes a restrictive orifice operatively associated with the duct means causing pressure in the chamber to rise when condensate is heated.

4. Apparatus in accordance with claim '3 wherein said means for regulating said means for creating pressure in the chamber in excess of the pressure in the steam inlet includes a valve connected in the inlet line to control flow of the heating medium therethrough to the chamber; and

control means operatively connected to the valve for automatically adjusting the valve to control flow of the heating medium in accordance with pressure in the chamber, and having a sensor disposed in the chamber for sensing such pressure.

5. Apparatus in accordance with claim 3 wherein said means for regulating said means for creating pressure in the chamber in excess of the pressure in the steam inlet includes a valve connected in the inlet line to control flow of the heating medium therethrough to the chamber; and

control means operatively connected to the valve for automatically adjusting the valve to control flow of heating steam in accordance with the pressure drop across the restricted orifice, and having a sensor disposed on each side of the restricted orifice for sensing pressure thereat.

6. Apparatus in accordance with claim 3 wherein said means for regulating said means for creating pressure in the chamber in excess of the pressure in the steam inlet includes a valve connected in the inlet line to control flow of the heating medium therethrough to the chamber; and

control means operatively connected to the valve for automatically adjusting the valve to control flow of the heating medium in accordance with the level of condensate in the chamber, and having :a sensor in the chamber for sensing the level of such condensate.

7. Apparatus in accordance with claim 3 wherein said means for regulating said means for creating pressure in the chamber in excess of the pressure in the steam inlet includes a valve connected in the inlet line to control the flow of the heating medium therethrough to the chamber; and

control means operatively connected to the valve for automatically adjusting the valve to control flow of the heating medium in accordance with the differ ence between the levels of condensate in the chamber and the condenser, and having a pair of sensors for sensing liquid levels of which one is disposed in the chamber and the other is adapted to be disposed in the condensor.

8. Apparatus in accordance with claim 3 wherein said means for regulating said means for creating pressure in the chamber in excess of the pressure in the steam inlet includes a valve connected in the inlet line to control the flow of the heating medium therethrough to the chamber; and

an analyzer connected to the outlet and the valve for analyzing the content of noncondensable elements in the condensate released from the chamber and automatically adjusting the valve to control the flow of the heating medium in accordance with the results of such analyzing.

9. In combination with a condenser having a casing with an inlet adapted to receive steam to be condensed, a tube bundle in the casing with a cooling medium passing therethrough for condensing steam, a reservoir in said casing below said tube bundle for receiving condensate resulting from condensation, and equipment in said casing for removing noncondensable elements from the condenser after being released from the steam; apparatus for removing noncondensable elements from the condensate, said apparatus comprising:

a chamber means disposed in the casing for processing condensate to free noncondensable elements therefrom, and having an outlet for releasing condensate from the condenser;

a wall disposed between the reservoir and the chamber having an opening therethrough for allowing condensate in the reservoir to pass into the chamber, said opening positioned below the level of condensate 6 in said reservoir to form a fluid seal between the reservoir and chamber;

means operatively associated with the chamber for freeing noncondensable elements from condensate in the chamber, and for creating pressure in the chamber in excess of pressure in the steam inlet; and

duct means in the casing and in communication with the chamber for receiving noncondensable elements freed from the condensate and releasing such elements into the inlet flow of steam to be condensed.

10. The combination in accordance with claim 9,

wherein:

11. The combination in accordance with claim 10,

wherein:

12. The combination in accordance 'with claim 11, and

further comprising:

a valve connected in the inlet line to control flow of the heating medium therethrough to the chamber; and

13. The combination in accordance with claim 11, and

further comprising:

14. The combination in accordance with claim 11, and

further comprising:

control means operatively connected to the valve for automatically adjusting the valve to control flow of the heating medium in accordance with the level of condensate in the chamber, and having a sensor in the chamber for sensing the level of such condensate.

15. The combination in accordance with claim 11, and

further comprising:

a valve connected in the inlet line to control the flow of the heating medium therethrough to the chamber; and

control means operatively connected to the valve for automatically adjusting the valve to control flow of the heating medium in accordance with the difierence between the levels of condensate in the chamber and the reservoir, and having a pair of sensors for sensing liquid levels of which one is disposed in the chamber and the other is disposed in the reservoir.

16. The combination in accordance with claim 11, and

further comprising:

an analyzer connected to the outlet and the valve for analyzing the content of noncondensable elements in the condensate released from the condenser and 7 automatically adjusting the valve to control the flow of the heating medium in accordance with the results of such analyzing.

References Cited UNITED STATES PATENTS 467,715 1/ 1892 Dugan 55-208 X 1,180,786 4/ 1916 Munzinger 55-208 X 1,592,195 7/ 1926 Fothergill 55208 X '8 3/ 1927 Jones 55-208 X 7/ 1929 Hodgkinson 165-412, 7/1929 Taddiken 1, 5 -112 FOREIGN PATENTS 2/ 1929 Great Britain.

ROBERT A. OLEARY, Primw y Exmmin'er.

Claims

9. IN COMBINATION WITH A CONDENSER HAVING A CASING WITH AN INLET ADAPTED TO RECEIVE STEAM TO BE CONDENSED, A TUBE BUNDLE IN THE CASING WITH A COOLING MEDIUM PASSING THERETHROUGH FOR CONDENSING STEAM, A RESERVOIR IN SAID CASING BELOW SAID TUBE BUNDLE FOR RECEIVING CONDENSATE RESULTING FROM CONDENSATION, AND EQUIPMENT IN SAID CASING FOR REMOVING NONCONDENSABLE ELEMENTS FROM THE CONDENSER AFTER BEING RELEASED FROM THE STEAM; APPARATUS FOR REMOVING NONCONDENSABLE ELEMENTS FROM THE CONDENSATE, SAID APPARATUS COMPRISING: A CHAMBER MEANS DISPOSED IN THE CASING FOR PROCESSING CONDSENATE TO FREE NONCONDENSABLE ELEMENTS THEREFROM, AND HAVING AN OUTLET FOR RELEASING CONDENSATE FROM THE CONDENSER; A WALL DISPOSED BETWEEN THE RESERVOIR AND THE CHAMBER HAVING AN OPENING THERETHROUGH FOR ALLOWING CONDENSATE IN THE RESERVOIR TO PASS INTO THE CHAMBER, SAID OPENING POSITIONED BELOW THE LEVEL OF CONDENSATE IN SAID RESERVOIR TO FORM A FLUID SEAL BETWEEN THE RESERVOIR AND CHAMBER; MEANS OPERATIVELY ASSOCIATED WITH THE CHAMBER FOR FREEING NONCONDENSABLE ELEMENTS FROM CONDENSATE IN THE CHAMBER, AND FOR CREATING PRESSURE IN THE CHAMBER IN EXCESS OF PRESSURE IN THE STEAM INLET; AND DUCT MEANS IN THE CASING AND IN COMMUNICATION WITH THE CHAMBER FOR RECEIVING NONCONDENSABLE ELEMENTS FREED FROM THE CONDENSATE AND RELEASING SUCH ELEMENTS INTO THE INLET FLOW OF STEAM TO BE CONDENSED.