US1654260A

US1654260A - Deaerator

Info

Publication number: US1654260A
Application number: US54583A
Authority: US
Inventors: Russell C Jones
Original assignee: Griscom Russell Co
Current assignee: Griscom Russell Co
Priority date: 1925-09-04
Filing date: 1925-09-04
Publication date: 1927-12-27
Anticipated expiration: 1944-12-27

Description

Dec. 27, 1927. 1,654,260

R. c. JONES DEAERATOR Filed Sept. 4. 1925 CrLNVENTOR W fluzflwwk ATTORNEY all) ill)

' in series relation.

l uterited lllec. 27. 1927.

UNITED STATES PATENT OFFICE.

RUSSELL C. JONES, 01" BRONXVIILE, NEW YORK, ASSIGNOR TO THE GHISCOM-RUSSELL COMPANY, OF NEW YORK, N. 'Y.,

a oonronn'riou or DELAWARE.

nnanna'ron.

Application filed Qeptember The presentinvention relates to decorating apparatus for steam generating systems and has to do with the furnishing of substantially as free Water to the boilers.

lVaier as supplied to a steam generating plant usually contains relatively large quanwith the result that pitting and corroding.

occurs. it is therefore common practice to subject the boiler feed water to a degassing trez'irti'nent before the Water 15 admitted to the boilers in order that the injurious may be removed from solution and expelled from the system.

Various types of apparatus for deaerating boiler feed Water have been proposed. For instance. it has been proposed to deaerate the ater in an apparatus consisting of two chambers through which the *ater passes The iirst'of these chain-- hers is a heating" chamber and in this chamber the Water is heated to a temperature approaching its boiling point under the pressure conditions n'iaint'ained in that chamber. 'l. he heated Water from this chamber is then admitted to the second chamber Where ebullition occurs either as the result of additional heating steam admitted to the second charm her or asthe result of reduced pressure in the second chamber in which latter case cbullition occurs by reason of the contained heat of the liquid. It has also been proposed to deaerate Water by dripping it upon a heated surface in which case the liquid is usual ly sprayed upon a bundle of heating; tubes so that the liquid runs over the tube surfaces in thoform of a thin film and is heated by reason of its contact With the tubes. De aeration is satisfactorily accomplished if the liquid to be deaerated is heated to its boil- -ing point corresponding to the pressure under which it is maintained and is then allowed to remain subjected to these con ditions for a suilicient length of time to permit all of the contained gases to remove themselves "from the solution.

ln copending application Serial No. 600,- 178, filed hloven'iber 10, 1922, in the name oi Joseph Price and assigned to the present as- 4, 1925. Serial No. 54,583.

signee, there is disclosed a deaerating ap paratus which consists of a containing shell in the bottom oi which is maintained a principal body of the liquid under treatment. The Water to be deaerated is admitted at the top of the chamber and falls over a series of bz'iil'les until it eventually reaches the principal liquid body in the lower part oi; the apparatus. Heating steam is preferably admitted. by means of a perforated pipe submerged in the liquid body so that the bubbling of the steam through theliquid "will e'llect an agitation and Will thus assist in bringing the solution to equilibrium and consequently in effecting complete removal oi dissolved gases. 'lhe present application is in a sense a development and improvementon the apparatus disclosed in this copending application.

In the present apparatus, the liquid is admitted at the upper portion of the unit and falls downwardly through the apparatus over a series of ballles which. tho poughly agitate it and distribute it as a aim of falling drops and the liquid eventually accumulates in a principal body of liquid, or 85111111] in the lower part of the apparatus. A. heating unit consisting of a plurality of heat transferring tubes is submerged in the principal liquid body, and heating steam is passed through these tubes at a relatively high velocity. This heating element causes ebullition of the liquid body and thus makes "for thorough scrubbing or removal of gases from the liquid body. The major portion oi? the steam admitted to the heating tubes passes the tubes uncondensed and this steam is then brought into direct contact with the incoming water to thus ell'ect eiiieient preheating of the Water. A slight pressure difference is preferably maintained between the in terior of the heating element and the interior of thedeaerating chamber to thus insure boiling of the liquid in the lowerpart of the apparatus.

The accompanying drawings illustrate a preferred embodiment of the invention. In said drawings Figure 1 is a vertical sectional 'vieW taken centrally through a deaerating view similar to Figure .2 illustrating an au tomatic pressure control system for regulating the admission of steam to .the interior of the shell.

Referring to the drawings, 1 indicates the containing shell or housing of the deaerator in the lower portion of which a principal body of liquid 2 is normally maintained. The incoming water enters at the top of the apparatus through the line 3, and a valve 5 in this line operated through a linkage 7 by means of a float 6 regulates for substantially constant liquid level in the apparatus. The incoming liquid passes down the length of the apparatus over a series of battles 9. Alternate bafiies as shown are provided with central openings and the intermediate bailies are provided with annular passages at their outer edges so that the steam and gases rising through the apparatus assume a tortuous path as indicated generally by the arrows and are thus brought into repeated and intimate contact with the liquid spray descending through the apparatus. The uncondensable gases are drawn out of the apparatus through the vent or discharge line 11. WVithdrawal of these gases is preferably effected by means of a steam ejector 12 connected tothe line 11 as shown. Deaerated Water may be conducted off through the line 13 provided near the bottom of the shell 1.

Submerged in the principal body of liquid in the, wer portion'ot the apparatus is a bank of eating tubes 14. These tubes preterably extend between rigidly spaced headers 15 asshown and are slightly bowed so that by subjection to a material change in tem perature, the tubes will fleX and will thus loosen and crack off deposits of scale which may have accumulated on them. A trap 16 is provided to conduct oit condensate from the discharge header of the tube element. The steam employed in the heating tubes 14 may be derived directly from the boiler or from any other convenient source. The amount of steam admitted to the tubes 14 is such that but a small proportion of it will be condensed in its passage through the tubes. It is conducted through the tubes at a relatively high velocity and thus affords a correspondingly high eiliciency of heat transfer.

The steam passing the heat-transferring tubes 14 uncondensed enters line 17, from whence it is passed into the interior of the deaerating chamber through the medium of the orifice plate 18. The size of the orifice in the plate 18 is so chosen as to maintain a. slight pressure difference between the steam Within the tubes 14 and that within the deaerator shell 1. This pressure differential may be from, say, oneto five pounds per square inch. In this fashion. a slight temperature difference is maintained between the steam within the heating tubes 14 and.

the water in the shell which diiference is sufis accomplished. The steam entering the dcaerating chamber through the oritice plate 18 comes immediately into direct contact with the incoming water flowing down over the baiile plates 9.

Ordinarily, all of the steam is passed through the tubes 14 and then into the deaerat-ing chamber through the orifice plate 18 excepting, 0t course, that portion of the steam which is conden ed, and withdrawn through the trap 16. Under certain circumstances it may, however be desirable to ad mit a certain amount of steam directly to the deaerating chamber without iirst causing it. to traverse the heating tubes 14. lVith this situation,the valve 20 in steam line 19 is opened to a certain extent and a desired amount of stean'i admitted directly into the deaerating chamber, while at the same time, a desired portion of the steam passes down through the line 21 and enters the submerged heating element 14 after which the uncondcnsed portion of thc'stean'i iind's its way through line 17 and oriiice plate 18 into the deaerating chamber 1.. The valve 20 is a pressure reducing valve designed to maintain in the dcacrating chambcra pressure corresponding to that which the oritice plate 18 is intended to regulate. The pressure in the deaerator should be slightly below that in the heating tubes 14, for the purpose of insuring the temperature differential desirable in maintaining a continuous and satis; factory ebullition of the liquid body 2.

For the purpose of ati'ording an etlicicnt heat transfer a high velocity ot steam within the heating tubes 14 is desirable. This eii eet may be enhanced if desired by the provision of a multi-pass heating unit ot the type shown in Figure 2. In this ligure a two-pass unit is shown, and the steam is caused to travel the length of the unit two times at a relatively high velocity before it is passed alongto the line 17 and orifice plate 18. In this figure the heating elemcnt is built within the deaeratiing chamber and is provided with stay rods 23 for the purpose of rigidly spacing the tube sheets so that fleXure of the tubes to produce a scale cracle ing action can be obtained. It: is to be understood that this internal type ot heating element construction may be employed either with a single pass or a multi-pass unit.

In Figure 3 there is illustrated on automatic valve 23 for maintaining a Sl1lJFl':1Iltially constant pressure and temperature di tferential between the submerged heating element and the deaerating chamber. The valve here shown is a diaphragm

valve having lines

24 and 25 communicating lQspOtF tively with the pressure in the deaerating till chamber and the pressure in the submerged heating element so that the valve will regulate for constant pressure differential with the result that a, substantially constant temperature differential will also be n'iaintained.

The apparatus of this application. therefore allords a simple and inexpensive construction which insures thorough heating of the water under treatment to effect liberation of dissolved gases and a thorough scrubbing or mechanical agitation of the water to insure removal of these liberated gases from the liquid body. The heating, is accom: plished both through the medium of the submerged heating element and through the mo dium oi the steam admitted to the deaerating chamber into direct contact with the incoming finely divided liquid. The i'i'iechanical agitation of the liquid body is accomplished by reason of the ebullition of the liquid effected due to the submerged heating element. This action is aided by reason of the pressure differential maintained between the interior of the submerged heating element and the deaerating chamber.

ll claim:

1. Deaerating apparatus comprising a containing shell, means for normally maintaining a body of liquid in the lower portion of said shell, means for admitting incoming liquid above said body of liquid and allowing it to fall under the influence o'f'gravity into the lower portion of the shell, a heating element submerged in the liquid within said shell, means for supplying heatingsteam to said element, means for supplying heating steam to the said containing shell above the liquid level therein and means for maintaining a temperature differential between said submerged heating element and the space within said shell whereby ebullition ot the said liquid body is insured.

2. Deaerating apparatus comprising a containing shell, means for normally 1naintaining a body of liquid in the lower portion of said shell, means for admitting incoming hquid above said body of liquid and allowing it to fall under the influence of gravity into the lower portion of the shell, a heating element submerged in the liquid within said shell, means for supplying heating steam to said submerged heating element to ell'ect ebullition ot the liquid within said shell, means for conducting steam passing said heating element uncondensed into the containing shell above the liquid level therein and means for maintaining a pressure dililierential between the said submerged heating'element and the said containing shell.

' 3. Deaerating apparatus comprising a con-- taining shell, means for normally maintain ing a body of liquid in the lower portion elf said shell, means for admitting incoming liquid above said body of liquid and allow ing it to fall under the influence o'lt gravity into the lower portion of the shell, a heating elen'ient submerged in the liquid within said shell, means for supplying heating steam to said' submerged heating element to ellect ebullition of the liquid within said shell,

means for conducting steam passing said heating element nncondensed into the containing shell above the liquid level therein and means for maintaining a pressure diller ential between the said submerged heating element and the said containing shell compris ng a valve interposed between the dis charge end of said submerged heating elc ment and the interior of said containing shell, said valve being actuated according to the pressure dillerential between said heating element and said shell.

4c. Deaerating apparatus COITlPlflSlllg a containing sliclhnieans for normally maintaining a body of liquid in the lower portion of said shell, means for admitting liquid to be treated above said body of liquid, a heating element submerged in the body of liquid within said shell, means for passing steam through said heating element at relatively high velocity and means for passing into the ,deaerating chamber, above the level oi? said liquid in the lower portion of said shell, all of the steam issuing from said heating element uncondensed.

5. Deaerating apparatus comprising a shell, means for normally maintaining a body of liquid in the lower portion oi said shell, means for admitting liquid to be treat ed above said body of liquid and allowing it to fall under the influence OTE gravity into said principal body of liquid, a submerged heating element in the lower portion of said shell, means for supplying a portion of the heating steam directly to the containing shell above the level of liquid therein, means for supplying the remainder of the heating steam to said submerged heating elementand means for admitting to the containing shell the steam passing said submerged heating element nncondensed, pressure regulating means being provided for maintaining a temperature difierential between said submerged heating element and the space within the containing shell to thereby insure cbullit-ion of the said body of liquid.

6. Deaerating apparatus comprising a shell, means tor normally maintaining a body of liquid in the lower portion of said shell, means for admitting liquid to be treated above said body'of' liquid and allowing it to fall under the influence of gravity-into said body of liquid, a submerged heating element in the lower portion of said shell, means for supplying a portion or the heating steam directly to the containing shell above the level of liquid therein, means for supplying the remainder of the heating steam to said submerged heating element and means for admitting to the containing shell the steam passing said submerged heating element uncondensed, pressure regulating means being provided for maintaining a temperature differential between said submerged heating element and the space with in the eontaining shell to thereby insure ebullition of the said body of liquid, said means comprising a conduit having pressure reducing means therein whereby a temperature difi'erentiai is maintained between the X0 fluid in said heating element and the vapor space above said body of liquid suflivient to permit ebullition thereof.

In testimony whereof I afiix my signature.

:IUSSELL C. JONES.