US1780781A - Condenser - Google Patents

Description

Nov. 4, 1930. R. N. EHRHART CONDENSER Filed April 28 1926 T N E v m Fatented Nov. 4, 1930 UNITED STATES PATENT/OFFICE RAYMOND N. EHRHART, OF EDGEWOOD, PENNSYLVANIA, AssrGNoR T ELLIoT'r GOM- rANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORA ION OF. PE NSY VANIA coNnE sEE Application filed'April 28, 1926. Serial No. 105,169.

The present invention relates broadly to the art of heat exchangers and more particularly to heat exchangers of the character ordinarily referred to as surface condensers and especially applicable to the condensation of steam. V

It has heretofore been proposed in the art to Which the present invention relates to construct condensers having a plurality-of tube nests through which the steam has been adapted to pass. The present invention relates broadly to condensers of this type, and has for one of its objects to provide a series of tube nests receiving cooling Water in series and steam flow in parallel.

Another object of the invention is to pro vide tube nests of the general character referred to adapted to not only receive steam in parallel but in different amounts. 7

Still another object of the invention is to provide'improved means in a condenserhaving a plurality of tube nests for efiecting the ofitake of the non-condensible gases. In the accompanying drawings there are shown more or less diagrammatically, condensers embodying the present invention, it being understood that the drawings do not define the limits of my invention as changesin the construction and operation disclosed therein may be made without departing either from the spirit of the invention or the scope of my broader claims.

In the drawings,

Figure 1 is a transverse sectional View through a condenser constructed in accordance with the present invention,

Figure 2 is a longitudinal sectional View through the condenser of Figure 1 illustrating the matter of supplying cooling water to the tube nests, and V Figure 3 is a view similar to Figure 1 illustrating a modified embodiment of the present invention.

' A condenser constructed in accordance With the present invention may comprise a shell 2 of any usual construction having a vaporinlet 3 and a condensate outlet 4.

Arranged within the condenser shell is an upper tube nest 5 preferably spaced from the 50 shell in such manner that both the top and sides of the tube nest are adaptedfto receive steam directly from the steam inlet. Locatedbelow the tube nest 5- is a second tube nest 6, the tube nest preferably beinglocated in such manner that a substantial space 7 is provided therebetween. By reason of this construction it will be apparent that vapor from the inlet 3 may pass directlyitothe tubes of the nest 5 throughout substantiallythe whole of that portion of the perimeter of the tube nest facing the inlet andat the same time, vapor may likewise pass, by reason of the side passages 8 and the space 7, to the tubes of the nest 6. This provides a construction inwhich' there may be a steam flow in parallel through the different nests,

it The construction is preferably such that whilethe nests receive steam in parallel, they receive cooling Water in series. This may be accomplished by providing a header 9 at one end of the condenser having a water inlet 10 supplying cooling Water to the tubes of the lower nest. The Water, after passing through the tubes of the lower nest enters the header 11 at the opposite end of the condenser by means of which it is returned through the tubes of the upper nest, the header 9 having a partition 12 insuring a flow in series through the tube nests as set forth. The cooling water ,may then be removed from the header 9 through the outlet 13."

It will be apparentto those skilled in the art that ma construction in which the numberof tubesin-the respective nests is sub stantially equal, as indicated generally, for example, in the accompanying drawings, and with a waterflow through the tubes in series, the averagewater'temperature in the lower tube nest will be lower than the. average water temperaturev in the upper tube; nest due to the heat abstracted from the vapor in the lower :nest Under, these conditions, more steam willbe condensed by the colder tube nest than by the warmer tube nest. In asmuch as the length of thefiow pathfor both nests oftubes is substantially the same, and inasmuch as the introductory area for the steam is substantially the same for both through the nest 5 due to their different steam condensing capacities. The loss of pressure, due to steam flow, varies approximately'as the square of the amount of steam. Under these circumstances, assuming a condition of operation,,forexanrple, in whichthe nest 6 handles approximately twice as much steam as the nest 5, there will be a loss of pressure through the nest 6 which is approximately essariily someslightvdifference in pressure between these two points must exist. .Under these conditions,- i-if I 1 each of, the-tubv-nests is-allowed to develop its own :natural con- (lensing-capacity, the natural condition of pressureat the flow termini of the respective nests "will bematerially-different ifeac'h nest accomplishes'its full share of condensing capacity incident to water temperatures;

S'inceit is desirable to efleot the 'ofl'ta-ke of non-condensible gases from both of the tube nests, and since these non-condensible gases must be *taken o'fl under the' conditio'ns referred'to from points adjacent the flow ter mini through thenests whichpoints are at dijfiierent pressures, it will be obvious that in condensers as heretofore constructed hav ing a single air'o'fftake, undesirable conditions' are encountered- 'According' to the present invention, there is provided an air o'fiTtake 14 for the nest 5 and a second 'air' 'oiftake 15 for the nest 6. Theseofftakes, as indicate din Figure 1, may be connected to 1 separate; ejecting means, not shown, having characteristics suitable to the pressures which exist at the respective r'fiow termini otthe tube nests.

"If desired,the o fitakes 'l i'and 15*may beinterconnected as by a: pipe 16 having a throttling valve 17 therein eiiective forxdissip ating the fpressuredifi'erence at the respective flow termini, or maintaining this difference, whereby acommon ejecting means may beiutilized. Y

The nests of tubes fin-addition to having the 'space :7 "between them, are 5 preferably further separated. by downwardly and out- "wardl y inclined baifies 181 connected at ltheir inner edges and constructed to cooperate H rem-tear directing condensate as indicated 1 'at""l9'across*the space? indirect contact with live steam wherebygnotfonly Will the temeraturefof the -condensate be increased, but "effective iet condensingaction on the steam :wi-ll be obtained Thev a'lvantagesofthe present invention -ar;ise from' the provisionof a surface con terminiftherethrough.'

denser in which steam is fed to different portions separated by means constituting a wall,

and in which cooling water temperatures in the respective portions are different.

Other advantages of the invention arise from the provision ofa condenser having condensing portions separated bylawall, and

havingseparate offtakes communicating with i said portions, and'preferably with the flow Stillothera'dvantages arise from the provision of a surface condenser in which a plu rality ofportions receivesteam in "parallel and .of d-ifieringamounts, this condition preferably' being accompanied by a flow of coolingwaterat different temperatures through i the respective portions. 7

1' Still further. advantages ariseffroni the provision of a condenser having a plurality of .tubeanests having difi'erent condensing capacities with means for maintaining different pressures at thepointsot non-condensible gas ofitake from the respective portions.

.Iclaimz 1,

1. Ina surface condenser, a shell having a steam inlet a wall in said shell providing free steamflowspaces between at least two-0f its edgesand the shell and providing a freesteam space therebelow, a tube nest on each side of said Wall, means forpassing cooling 3 Water through said tube nests n series, and

means forsubjectingthe respective tube nests at substantially their steamiflow termini to' different pressure conditions,

2. In a surface-condensenashell having a steaminlet, a, wall in said shell gproviding free steam flow spaces between at least two of its edges andv the shell and providing a free steam space therebelow, a tube nest on each. side of saldwall, means for passing coollng water through said tube-nestsin -'seri es, .and means for taking off non-'condensible gases from each of. said nests under different 'pressure conditions.

a V 3; lnra'tcondenser, superimposed tube nests,

a common steam inlet for both of saidnests, there being a flow passage surrounding one nest forsupplying steam :to the other nest, and 'a condensate collecting'b affle intermediate said nests, there being asep'arate air offtake under ,difierent pressure conditions for each of saidnests. v V. i '4. Inacondenser, superimposed tube nests, a common steam *inlet :for both of saidlnests, there being a flow passage surrounding one nest for supplying steam :to the other nest,

and a condensate collecting 'bafiie' intermedi} ate said nests, there being a separateairofitake for each of said nests, 'one of 'said ofi- 7 takes extendingthrough-saidbaflie. I

51 In'a condenser, superimposed tub'ej nests each providing af-ste'am fiow zone having its area decreasing the direction-of-rsteam flow, a common steam'ilnlet for-both oflsaid nests,"-and a separate Iair ofitakeoperalile mi; 1

der respectively different pressures for each of said nests. V

6. In a condenser, superimposed tube nests each providing a steam flow zone having its area decreasing in the direction of steam flow, a common steam inlet for both of said nests, and a separate air ofitake for each of said nests, there being a battle intermediate said nests through which one of said air 011'- takes communicates. g

7. In a condenser, an inlet, superimposed tube nests each having a steam receiving p01"- tion facing said inlet, the condenser being formed with a free steam receiving space above each tube nest, connections forindividually withdrawing noncondensable gases from said nests, and means for maintaining difierent pressure conditions in each of said connections.

8. In a condenser, an inlet, superimposed tube nests each having a steam receiving portion facing said inlet, the condenser being formed with a free steam receiving space above each tube nest, connections for individually withdrawing noncondensable gases from said nests, each of said tube nests providing a steam flow space decreasing in area in the direction of gas ofltake, and means for maintaining difierent pressure conditions in each of said connections.

9. In a condenser, an inlet, superimposed tube nests each having a steam receiving portion facing said inlet, the condenser being formed with a free steam receiving space above each tube nest, and means for separately withdrawing noncondensable gases from said nests, there being a baflie intermediate said nests around Which the steam passes to one of the nests and through which air from the other nest is taken 0E.

RAYMOND N. EHRHART

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