US2647495A - Vapor generator - Google Patents

Description

Aug 4, 1953 w. T. MOORE VAPOR GENERATOR Aug. 4, 1953 Filed June 2, 1949 000000000000 A00 OOOOOOOOODOgg OOOO W. T. MOORE VAPOR GENERATOR 2 sheets-sheet 2 SO o oor

G OOOOWQOCOOOOOG 00 OO O0 004700000000000@ FIGS Patented Aug. 4, 1953 VAPOR GENERATOR William T. Moore, Elmhurst, Ill., assignor to The Babcock & Wilcox Company, New York, N. Y., a corporation of New Jersey Application June 2, 1949, Serial No. 96,731

Claims.

This invention relates to fluid heat exchange apparatus in Which a vapor generator such as a water-tube type of steam generator is utilized to absorb heat from a gaseous medium at a high temperature (i. e., 200G-2600" F.) and under substantial pressure (i. e., 250-350 p. s. i.)

The invention involves an exterior pressure vessel of sufficiently large dimensions (i. e., height 50-100 feet, diameter 10-20A feet) to house the gas generator or furnace component and the tubular pressure part components of a vapor (or elastic fluid such as steam) generator with provisions for the necessary circulation of the internal and external heat exchange fluids involved.

As an example of the use of the invention, it may be employed in chemical processes in which the exterior pressure vessel constitutes a shell through which gaseous reactants or reactance products pass at temperatures of the order of 2500 F. and pressures of the order of 300 p. s. i. For example, oxygen, natural gas, or methane may be supplied to the shell as reactants, and the high temperature products of their reaction are then passed overl the heat exchange parts of a vapor generator. The vapor or steam generator is employed, in such a process, to control the temperature of the gaseous products. In some processes it is important that the gaseous reactance products be reduced from a temperature of the order of 2500 F. to a temperature of the order of 600? F. This illustrates Ione of the results accomplished by the invention, and the -overall process more effective. By this arrangement, provisions which must be made for differential movements of the pressure parts and .the shell are minimized, and there is less pressure drop in the gases passing through the shell. The vapor generating system within the shell involves a bank of upright tubes having their upper `ends rigidly connected to a liquid and vapor drum and their lower ends t0 a liquid drum, the bank of `tubes and drum arrangement constituting an assembly which is supported by the shell at a position adjacent the upper drum.

' In a preferred embodiment of the invention,

ythe vapor or steam produced is conducted from 2 the upper part of the upper drum to a radiant superheater which includes a circular series of upright tubes arranged around the interior surface of the shell and functioning as shell wall cooling tubes to protect the shell against overheating.

In one process in Which the invention is employed, natural gas is burned with a .deciency of oxygen in a combustion chamber (or reaction chamber) disposed in the shell but below the vapor generator. These gases react to develop gaseous products which pass upwardly from the combustion chamber and are caused to recurrently pass back and forth transversely of the bank or banks of vapor generating tubes before they leave the shell at its upper part. The natural gas and the oxygen react under pressures of the order of 300 p. s. i. and are effective in creating gaseous products within the temperature range of 20002500 F.

The apparatus of the invention is illustrated by an embodiment which is disclosed in the accompanying drawings in which:

Fig. 1 is a vertical section on the line I-l of Fig. 4;

Fig. 2 is a multiple plane vertical section on the section line 2-2 of Fig. 4;

Fig. 3 is a horizontal section on the line 3-3 of Fig. 1;

Fig. 4 is a horizontal section on the line 4-4 of Fig. 1;

Fig. 5 is a fragmentary View of Fig. 4 on an enlarged scale;

Fig. 6 is a view in the nature of a vertical section on the line 6--6 of Fig. 3, particularly showing the manner in which the upper drum of the vapor generator is supported within the shell;

Fig. 7 is a partial elevation showing two adjoining superheater tubes and the manner in which they are secured to the shell;

Fig. 8 is a partial horizontal section on line 8-8 of Fig. 7;

Fig. 9 is a 'partial horizontal section on the line 9 9 of Fig. 1, showing a full stud tube construction employed in a furnace zone ofhigh temperature; and

Fig. l0 is a partial horizontal section on a line l U-lll of Fig. 1, showing a partial stud tube wall construction for a reaction zone of lower temperature.

The shell I0 is a Welded steel pressure vessel which may have a diameter of from l0 to 20 feet and a height o f 50 to 100 feet. It is fabricated to withstand internal fluid p-ressures considerably in excess of 300 p. s. i., and it is provided with gas inlets at its lower portion and a gas outlet such as l2 at its upper part.

Within the lower part of the shell IIJ is a combustion chamber or reaction chamber, ld with thick refractory walls through which there are gas inlet ports such as l and I8, these ports also extending through the shell l as indicated in Fig. 1. :In its upper part, the combustion chamber is provided with outlet ports such as 29 and 22, acting as a part of means directing high temperature gases over the heat exchange parts of the vapor generator.

The vapor or steam generator within the shell lil includes a transverse upper drum 2*!5 connected by banks 26 and 2E of steam generating tubes to a lower drum 3G. The tubes are expanded into tube seats in the drums in a manner well-.known in the art to form pressure tight connections, vand the entire unit is suspended within the shell `by means including an arrangement oi elements such 'as that particularly indicated vin Fig. '6. This arrangement involves a roller 'supporting bracket 32 secured 'to the wal-l of the shell ill, and an upper bracket 3d secured to the drum 24. and resting upon 'a roller et, which, in turn, is supported by the bracket 32. There is a similar arrangement of drum supporting elements at 'each vside ci the shell, as indicated in Fig. 2.

The banks of `vapor 'generating tubes 26 yand 28 are separated by a 'diametrically disposed wall i Sl ('see Fig. ll) 'which `in'ciudes the large diameter upright d'own'corn'er tubes 'su'ch Aas fr0- 428. The spaces between these downcomer 'tubes 'are closed "by means shown 'as refractory 'material to ycomplete the Wallin the iorm indicated in Fig. 4. These downcomers, being 'straight 'tubes yand of greater structural 'strength than the smaller diameter 'tubes of the banks 2t Aand 2S, provide Aa 'major part of the support necessary for the lower drum 30. One of the down'comer tubes, the tube 11E, 'has a blow-'down ltube 50 extending Vtherethrough Afrom the 'lower part or the lower drum 3B to a position within the upper drum, indicated at '52 'in Fig. 2. From this position, the vblowndown tube extends laterally through the'clruln 'and shell 'walls to a blow-down valve (not .shown).. The lateral extension of the blow-d0wn tube is 'indicated at 5l '(Fi'g. '3) Itis provided'with thermal sleeve constructions 53 and .5d similar to that indicated 'at 'li'l -for -the 'feed water connection Il'l. rhe latter act as a `part of means for 'supplying 'the vapor generator Awith a liquid for circulation therethrough. Tubular connections 'lll and T39 for a gauge glass '6l have similar thermal 'sleeve constructions Vt3 and '65.

The lower part of 'the lower drum '3'0 is protected from the higher temperature gases Yadjacent the combustion chamber 'i4 by a refractory 'covering '5d which may 'be Jheld Vin position on the lower Vpart of lthe drum wall by metallic- 'projections Ywelded to Athe drum. l'This covering also extends over a manway opening 556 which is normally closed by ya plate B attached to 'the drum by appropriate or suitable holding means.

IBelow drum cover 51.5 'is a refractory vbody '60 for increasing the thermalprotection of the lower part of the drum 30.

The gaseous reaction products from 'the com- -bustion vchamber It pass 'through the outlets 20 i horizontally ,extending 'baffles "I0-Jil. The baffles "EG, l2, 1d, l5, 71, T9 extend radially inwardly from the shell to a position adjacent the inner rows or" tubes of the associated banks of tubes 26 and 28, and the remaining baffles extend from the wall 36 outwardly on both sides thereof to the outermost rows of the banks of tubes. The baiiles constitute means directing high temperature gases over the banks of tubes connecting the drum 24 with the drum 3G.

A vapor, or steam under pressure, passes from the upper part of the drum 26 to the circular inlet header of the superheater. This header may be formed by a number of arcuate sections such as '8i- Ell which are individually supplied with steam 'from the drum 2d by the tubular connections such as '9i-94 (Fig. 3). These connections `and the header constitute means connecting the superheater with the drum 24. Extending downwardly frorn each of the sections of the upper superheater header 803, are wall tubes such as the tubes 'd6-98. r'Zlhese tubes are held 'in position in substantial contact with the Wall ci the shell Ylll by means such as that indicated in YFigs. '7 and 18. This means includes a metallic sleeve it@ welded to the shell as indicated at H12. Slidably extending into the upper end of 'the sleeve itil is the downwardly extending portion let of a right angle bent rod. The 'upper portion l'd -of this rod is welded to the tube @i5 -as indicated at ldd. Asinrila-r rod H18 is secured to the tube t8 and 'has its upwardly extending portion disposed within the llower part of the sleeve ll. it is to ybe understood that such securing Adevices are distributed throughout the "length land width 'ci the wallfof ysuperhe'ater tubes which constitutes a lining for the 'shell l0.

In the higher temperature 'gas Zones, and prefcrab-ly up to the level of the A:baliies 'i2 and 71, Ythe superheater tubes 'are fully studded, as indicated in Fig. '9. 'The faces 'of these tubes toward the linterior o'i the shell, aswell as the 'side faces 'of the tubes, have welded 'thereon 'studs 'such las those indicated 'at H )-'11ll, 'and the 'shell :lining is 'completed "by a refractory material :stratum `such as it@ packed around the tubes and studs in a semi-'plastic condition, las is well-"known in the art. In a lower 'temperature 'zone the superheater tubes 'such vas 9E and '98 'are only partially studded, the races of the tubes ysuch as and '22 presented Mtoward the interior "of the shell are not 'covered with the studs :and refractory construction. 'The lower parts "of some of Vthe superheater tubes Aare Vbent 'around the gas ports t6 'and 'la `oi the combustion chamber, and all of `the superheater tubes extend below 'these ports 'to a connection with alower superheater header 30. Superhea'ted steam passes 'from the .circular header IS to an outlet header T32 which extends through an yopening T315 lin the base or support .itt .for the shell lll. Connections between the A.-lfieaders 430 and |3.2 Aare .indicated at lm-M3.

In order :that :saturated steam -or vapor may be `conducted zdirectly :from the dr-um to Aone or .more safety vvalves and to 'the superheater, drum Y215 has connected therewith a tubular -'outlet 150 which extends through an opening fat the 'top of 'the .shell t0 :and 'lis v.connected 'therewith 1byr-a pressure tight Lexpansion iointfconsitruction such as W2. fllfle'tubular'outlet |950, withorwithout the -tubes 495| and Ithe superheater zand its connections, constitutes means connected with the va-por generating tribes and extending through :the shell Ill to constitute Ioutlet 'for-vapor unlll"der pressure. T'The' tubular outletl also constitutes -a safety valve conduit.' To provide 'for' access to the interior of the drum 24, there is ay manway construction |60 secured to the drum and aligned with another `manway construction |62 4which is secured to the shell l at the position indicated in Fig. 2.

constitutes a feed pipe connection extend- I ing through the shell at |12 and connected with the drum at |14-as means for the purpose of supplying the vapor generator with a liquid from which the vapor is to be generated.

y From the above description, it .will be noted that the shell of the v pressure .vessel acts as a column in which the steam ,generator is supported. The load of the pressure vessel and the steam generator isv taken at the base of the installation upon support |36. lThis support may be convenientlyl shaped, as.V 1a. cylinder which is in direct compression.

The superheater wall tubes 98 are supported in idirect compression from the header |30, this header being supported by theA shell I0, as by 4inwardly extending brackets |80 similar to the upper brackets 32, secured to the shell. With this permitted* without undesirable stress, by reason ,i

'of the looped construction of the superheater supplyl tubes such as SIL-94.

The support of the steam generator at a position near the brackets 34 permits the tubular "feed water connections, and other connections such as the gauge glass conduits 51 and 59. to be brought out of the pressure vessel at a'level coincident with the transverse axis of the upper drum 24. With this arrangement, there will ber very slight relative movement between such connections and the shell of the pressure vessel. What little movement thereby will be readily taken up by the bent or looped construction of these connections.

While in accordance with the provisions of the statutes I have illustrated and described herein the best form of my invention now known to me, those skilled in the art will understand that changes may be made in the form of the apparatus disclosed without departing from the spirit f of the invention covered by my claims, and that certain features of my invention may sometimes be used to advantage Without a corresponding use of other features.

What is claimed is:

1. In fluid heat exchange apparatus, a metallic pressure vessel consisting of an upright cylindrical shell of large volume, a vapor generator including upper and lower drums and connecting banks of vapor generating tubes disposed as a unit within the shell and pendently supported from the upper part of the shell, a row of large diameter downcomer tubes disposed between said banks of tubes and directly connecting said upper and lower drums, a high pressure combustion Vchamber within the shell, baiiles directing high temperature gases from the combustion chamber over said banks of tubes and to a gas outlet at the opposite part of the shell, tubular means through which the vapor generator is supplied with a liquid for circulation therethrough and the development of a vapor under pressure, a superheater including a row of closely spaced tubes disposed closely adjacent to and distributed in circular arrangement around the inner vof 'vaporvgenerating rtubes disposed as a unit ysurface of Athe shell, loopedtubular means connecting the vapor space of the upper drum with the upper ends of the superheater tubes, and a superheater outlet header secured to the shell and connected with the lower ends of the superheater tubes.

y A"2. In fluid heat exchange apparatus, a metallic pressure vessel forming an upright cylindrical shell of large volume, a vapor generator including upper and lower drums and connecting banks within the shell and pendently supported thereby, a row otspaced large diameter downcomers directly connecting said upper and lower drums, refractory meansA associated with the downcomer tubes to ll the spaces between them and complete a wallv extending across the shell and separating the banks of tubes, means directing high' temperature gases from one part of the shell over said banks of tubes and to a gas outlet at the opposite part of the shell, tubular means through which the vapor generator issupplied with a liquid for circulation therethrough and the development of a vapor under pressure, a superheater including a row of closely spaced tubes disposed closely adjacentto and distributed in 'circular arrangementl around the inner surface of the shell, looped tubular means connecting the vapor space of the up-per drum with the upper ends of the superheater tubes, and a header constituting a superheater outlet connected with the lower ends of the superheater tubes, said header being secured to the lower part of the pressure =vessel to form a bottom support for the superheater.

3. In fluid heat exchange apparatus, a large diameter metallic pressure vessel adapted for the passage yof high temperature and high pressure gases therethrough in normal operation, a heat absorbing unit heated by said high pressure gases including tubes vertically disposed within the pressure vessel, supporting means near the top of the pressure vessel for pendently supporting said heat absorbing unit, upper and lower drums included in said heat absorbing unit, the supporting means being connected to the upper drum, a feed water connection to the upper drum, a blow-down tubular connection extending from the lower drum and then through the upper drum and the wall of the pressure vessel to the atmosphere in the horizontal zone of said supporting means, a bottom supported superheater including upper and lower ring headers and a ring of upright wall tubes adjacent the wall of the pressure vessel, a safety valve conduit extending upwardly from the upper drum through the Wall of the pressure vessel, looped superheater supply tubes in communication with the safety valve conduit and the upper header of the superheater to supply steam to the latter, and tubular means extending from the lower header of the superheater through the wall of the pressure vessel for the delivery of superheated steam.

4. In fluid heat exchange apparatus, a large diameter metallic pressure vessel providing an upright cylindrical shell adapted for the passage of high temperature and high pressure gases therethrough in normal operation, a heat absorbing unit heated by said high pressure gases including tubes vertically disposed within the pressure vessel, supporting means near the top of the pressure vessel for pendently supporting said heat absorbing unit, upper and lower headers or drums included in said heat absorbing '7 unit, a fvaporrzaele liquid oomieotron 4.to upper dromer header, .1a :blow-'down tubular foon- Ymention extendtng :from the lower drum and then through the lupper drum'or 'header :and through 1the1x1/refiler the pressure vessel to the atmosphere in the horizontal zone of said supporting means, a h'ottom supported superheater inoludingupper ,and lower ring headers and arngof upright wall tubes adjacent the wall of the pressure vessel,

:a :safety valve conduit extending ,from .the upper ,I

drum or .header fof said unit :through the wall of 'the 'pressure vessel in :said :horizontal zone, lbowed :superheater Asteeply tubes -directly vconnecting the .safety valve oon'duitand'the upper header lof .the

superheater, .and tubular .means extending from Y l the .ll'ower .header of the superheater through the Wall of the pressure vessel .for the delivery of superheated ria-por.

f5. n =ilu-icl `heat 4exchange apparatus, an upright nylindrieal pressure vessel formi-ng va shell of arge volume, a ring of .upright Huid conduct- Wa'll leovzrlng tubes lcont-iguously 4arranged re1- atve .to the 'inner :surface fof the shell and vextending Vfrom a ,position near the bottom Vof the shell to a position .near its top, :a thick 'Walled refractory construction .presenting a .high 'temperature reaction `chamber within said ring of .tubes and disposed vat fthe lower part .of the shell, 4the upper part 'of the treaction chamber having openings xfor ithe upward exit yof high temperature :gaseous .reaction products, separated groups of horizontal-ly spaced upright vapor generating vtubes -disposed Within the shell above the reaction chamber, pressure parts .constituting upper and lower Huid Chambers which are connected rb'y the vapor generating tubes, means other than vsaid sap/or generating 'ltubes connecting said 'upper 'and lower xvoh'arnioers, ioafe means causing `the reaction 'products to pass over the groups of 'tubes in a plurality fof transverse gas passes,

8 means 'romaine fan yexit passage for the .reaction products near the top 4of the shell, .refractory baffle Ameans associated with the downcorners Aand separating groups fof tubes. means foormeet- :ing fthe rling of tubes to the :Huid l-systen'r of vthe 7vapor .generating itubes, said `last named means including header means and .bent tubular connections eommurucating `'with the upper header :lower hea-der means .at fthe .lower ends `of `said 'ring #of 'tubes and connected thereto, means yseoured to the shell for affording Abottom support for the lower .header means and sad ming `of tubes, and means `'secured to the upper zpant fof vthe .shell for pendentiy supporting .the groups of vapor generating tubes. i

T. MOORE.

.References -Cited in the Sle of `this -pastent STATES .Number Name "Date 91,294 Wilfong June 15, 1869 1,068,301 Bettington July 22, T913 21,270,621 Kestner June .25, 1'918 `175I343 Steinmuller VMay G, 1930 1,789,427 Belling e't Pa1. Jan. "20, 1'931 1,846,428 Kunz Feb. y23, 1932 1,881,275 Huff Oct. 4, v1932 l1,903,521 Taggart Apr. l1, 1933 1,9%,939 Noaok Feb. A2'?, 1934 i2,007,540 LaMontI July 9 '19.35 2,037,493 'Biersak 'et z9l1.. .llll1;)1. 14, 1936 .2,055,362 Peters Sept. 22, 1936 2,124,215 Stillman July '19, 1938 2,313,061 Frisch 'Mar v9, 1943 '2,383,634 Alexandrou Aug.'2l, 1'945 2,594,330 lllayhew Apr. '29 1952 .FOREIGN PATEN 'Number A"Country Date 12,004 'Greait'ritain Nov. '14, 41912

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