US1715456A

US1715456A - Multistage open heater

Info

Publication number: US1715456A
Application number: US728654A
Authority: US
Inventors: Russell C Jones
Original assignee: Griscom Russell Co
Current assignee: Griscom Russell Co
Priority date: 1924-07-28
Filing date: 1924-07-28
Publication date: 1929-06-04
Anticipated expiration: 1946-06-04

Description

June 4, 1929. A R. c. JONES MULTISTAGE OPEN HEATE original. .Filed July 28, 1924 2 Shees-Sheet l INVENTOR ATTORNEY June 4, 1929. A R. C. JNS 1,715,456

MULTISTAGE OBEN HEATER original Filed July 2s, 1924 2 sheets-sheet 2 N vENToR ATTORNEY Patented J une 4, 1929.

UNITED STATES PATENT oFFlcE.

RUSSELL C. JONES, OF BRONXVILLE, NEW YORK, .ASSIGNOR TO THE GIULSCGMruk RUSSELL COMPANY, OF NEW YORK, N. Y., A. CORPORATION OFDELAWARE. I

MULTISTAGE OPEN HEATER.

Application 1ed Ju1y 28, 1924, Serial No- 728,654. Renewed September 17, 1928.

The present invention relates to a steam generating system and has to do particularly with the preliminary heatingl of feed water on its way to the boilers.

5 The auxiliary apparatus and other steam utilizing devices of apower generating plant invariably furnish a considerable quantity of relatively low pressure steam which must be utilized in the system in order to avoid heat losses. This quantity of steam is usually accommodated by passing it into heat transferring relation with the boiler feed water, thus imparting to the feed water before it enters the boiler` heat Which-would be lost if the heating fluid were discharged to Waste. Modern steam power plant practice tends toward the use in the heating' of boiler feed water of both exhaust steam from the various apparatus of the plant and steam withdrawn or bled at different pressures fromvarious stages of the-plant turbine. AccordingL to the common prevailing practice, each of the different sources of steam is passed independently into heat exchanging relation with thev boiler feed water. The boiler feed water is passed into heat transferring relation with the respective sources of heating steam in the order of their ascending` pressures and temperatures, that is, the feed water first receives heat from the vsource of steam at the .lowest pressure and is successively treated by the other sources of steam at successively higher pressures. Each operation of transferring heat between the heating steam and the boiler feed water is'conducted as an independentloperation in a separate surface type heat exchanger provided for the purpose. It is an object of this invention to rovide a heater for preheating the boiler feed water which is adapted to receive steam from the plant turbine, or other sources, at different .Y pressures and utilize to advantage the ava-ilable heat of s uch`steam, yet which involves.

but a single unitary apparatus possessing the distinct advantages of moderate initial cost, minimum space requirements, notable operating eiiiciency and convenience of operation. In steam generating systems of the typereferred to the supply of boiler feed water com- 5.o-lmo'nly consists of low temperature turbine condensate together with whatever Water from the evaporators is necessary to supply the required make-up of the system. The

ll-'heating steam is commonly exhaust steam thus effecting the heat transfer by direct con-y Y tact of they fluids. I The invention contemplates the provision of a' plurality of compartments in the open heater. The heating vfluids from the several.

sources are admitted to the respective coin- -pa rtments at their respective pressures and suitable provision is made for passingthe boilerfeed Water thru the respective compartments in series relation. The Huid whichis pumped from each compartment to the next.

succeeding compartment consists of the Huid which was initiallyadmitted to thecompartment and in addition the condensate produced by the heating steam-which was admitted to that compartment and which was condensed by reason of its water.

It is an object of the invention to arrange the various chambers or compartments in which the heat transfer takes place in such contact with lthe cold feed eov fashion that the apparatus has avmarked iexibilitv of design, thus adapt-ing it for incorporation into whatever space' is available, and in such fashion that transfer of fluid from one chamber to the next may be conveniently and effectively accomplished. In carrying out this idea, the compartments are arranged at the same height, so that the number of compartments may be increased by increasing the lateral dimension, for instance the diameter, of theiheater.

yIt is a still further object of the invention to provide a multi-stage open heater of the class referred to of such construction that danger of water from the heater backingup into the turbine or other apparatus where it would cause damage is effectively avoided. To this end the liquid in each of the heat transferring chambers-is introduced at substantially the pressure of the incoming heating steam. As a further precaution. one embodiment ofthe invention contemplates an overflow control adapted to discharge water fromeach chamber into the next lower chamber in case an excessive amount of liquid accumulates.

Byway of example I have illustrated in the aceompanyingdrawings an apparatus embodying my invention. In said drawings:

Fig. l is a vertical section of a feed water heater embodying my invention;

Fig. 2 is an elevation taken at right angles to the view shown in Fig. 1 ;l I

Figs. 3 and 4 are transverse sections taken rFespectively on line 33 and line 4 4 of Fig. 5 is an elevation of a modified form of heater;

Fig. 6 is a top view of the modification shown in Fig. 5; and

Fig. 7 is a transverse section taken on line 7 7 of Fig. 5.V A

Referring to the drawings, 1 indicates the containing shell or housing of the heater and 2 is a vertical partition placed diametrically4 of the shell to divide the heater into two compartments A and B. The boiler feed water is admitted through the feed line 3 and is discharged into the upper end of compartment A through theinlet 4 from whence it indsit's way down through the apparatus and accumulates in the bottom of the compartment. the feed-line 3 regulates for a substantially constant liquid level in the compartment A. Heating steam is admitted through the inlet line 7 and circulates about freely within the compartment A coming into direct contact with the cold incoming feed water to thereby impart its availableheat to the feed water and at the'same time be condensed and` mingled with the feed water in the form of liquid condensate.

In order to facilitate the intermixture of.

the heating steam and the feed Water'andfto accomplish an efiicient and effective heat transfer between the two mediums, special revision is made for distributing the incoming liquid throughout the compartment. The incoming water entering through the inlet 4 falls into a compartment 8 formed between terposing a sheet of liquid between the steam.

inlet 7 and the air vent 13 thus'making it impossible for steam to escape through the vent 13 without rst passing into intimate contact with the incoming liquid.

The overflow from chamber 8 is accommodated ina chamber 14 formed between the annular partition 10 and the outer wall of the shell 1. The bottom of chamber 14 is also A float 5 operating a valve 6 in' One or two rows of perforations 12 perforated to discharge liquid down into compartment A as a curtain of falling rain and it is from chamber 14 that the greater portion of the liquid will ordinarily be discharged. The smaller 'chamber 8 is provided particularly'for operation at light loads to insure a complete curtain of falling liquid through which the heating steam must pass before it can escape from the heater. At lightloads, if the annular partition 10 were not employed .and the incoming liquid were not discharged into the chamber 8, the incoming liquid might have some tendency to spread out in a layer on plate 11. butl most of the liquid would pass through the plate at a point substantially beneath the inlet 4 and lthe supply of incoming water would not be sufficient to form a closed curtain of falling drops extending entirely around the chamber and thus presenting a solid curtain of water with which the heating steam must contact.

With this situation, it would be possible for steam to find its way through the gaps in the curtain of falling liquid and escape uncondensed through the outlet 13. A perforated distributing plate '35 may be provided to check the falling liquid and redistribute it Cil before permitting it to pass on to the principal body of liquid in the lower portion of the compartment. The steam entering at the inlet 7 circulates about as indicated by the arrows coming into intimate contact with the fall ing liquid until it isconipletely condensed.

Uncondensible vapors rise to the top of the shell and ind their way out at the vent 13.

"Ihe boiler feed water is passed successive- 'lys through compartments A and B. The feed water entering compartment. A is heated by reason of the heating steam supplied to that compartment and this Vheated water, togetherwith the condensed heating steam formed in the compartment which has become intermixed with the original supply of feed water, is withdrawn at the bottom ofthe compartment. A through the discharge line 1,5 and by means of a suitable pump 16 is passed through line 17 into the upper end of compartment B in the same fashion as in compartment A. Heating steam for compartment B is admitted through inlet line 18 and imparts its available heat to the supply of partially heated liquid entering from compartment A. In compartment B the feed water is further heated and is augmented by the condensate derived from the heating steam supplied to this compartment.. The

liquid, consisting of feed water and comthe main turbine is used for heating the boiler feed Water, the feed Water may be heated successively by steam at atmospheric pressure from the exhaust steam line of the plantand byv bleeder steam from the turbine at some otherpressure, say, at 3 0 lbsyper square inch absolute. In this instance, the steam at atmospheric pressure would be admitted to compartment and the heated feed Waterl from compartment A to'gether'vvit-h the'condensed exhaust steam' would then be transferred into compartmentv B, which compartment wouldreceive the bleeder steam at 30 lbs. per square inch pressure.l 4The compartments 'A and-B are maintained respectively at substantially the pressures f the respectivesources of heatingsteam. The pump .16 serves to transfer the IWater from the low er to the higher pressure. By thus maint-ain-l ing eachpOmpartment of the heater at substaniiially the pressure of the incoming heat- 5 5 ".f'time, the heating steam is ordinarily passed ing steam, danger of backing up of the .Water v'into the turbine or other apparatus furnish- ,ingthe heating steam isa-voided. In bleeder stearn heaters commonly in'use atthe present insidethe heating tubes and the water surrounds the tubes at a much higher pressure 'than is maintained inside the tubes. VVit-h `sult inthe discharge of a large quantity of high pressure water into the steam space,`

this situation, a leaky tube may readily re-v .'With the result that the Water 4will back up ."into the'turbine and probably cause serious 35 i A I damage to the turbine rotor.

' For the purpose 'of controlling the supply of-.steam admitted to the respective compartrnents of the heater, an orifice may be successfully used. I have here shown an orifice' plate so interposed in the heating steamV 'line at the point Where the heating steam enters the heater. The orifice plate is inserted at a joint in. the piping and contains a circular oriiiceA of predeterminedsize adapted` to deliver the proper amount of steam into` the heater. 'lhe pressures of th'e respective supplies ofl heating steam remain substantially constant and, with this condition, a con- .stant flow of heating steam into the respective compartments will be maintained by means of the controlling orifice. It will be understood, however, that the orifice control l is merely a matter of convenience and is not essential to the operation of the device.

The apparatus shown .in Figures 5 to'7 is provided with three compartments vseparated by verticalpartitions 2 extending the length of the shell 1. Gold liquid and heat.- ing steam at different pressures are admitted to the various compartments in the same fashion as above described and float con.-

trolled valves are provided for maintaining a substantially constant liquid level in each compartment. The feed Water is preferably pumped through the three compartmentsin.

succession, the liquid leavingbeach comparte'A ployed is ordinarily 4free fromimpurities,

suitable provision may-bemade for separating oil. from the steam or Water from low pressure steam before admission tothe heater if desired. Other changes may be made within the scope of theappended claims.-

Iclaim.: l 'l 1. In a steam generating system, a heater for heating boiler feed water comprising a vertical Acylindrical tank subdivided vertically by partitions into ajplurality of'compartments, .meansl for supplying" heating steam at prgressively higher'pressures to said respectivevcompartments, and means for passing boilerfeed `water successively through 'saidcompartments and a capfor the upper end of said .tank having vertical partitions corresponding in position to the partitions inA said tank, and forming compartments in said cap corresponding tothe compartments of the tank, each of said compartments having an outlet for uncondensii'" ble gasesand an inlet for water to be heated surrounding said gas outlet, and means associated-with each of said water inletsfor distributing the incoming Water in a curtain of spray surrounding the gas outlet. g 2. Ina steam generating system, a heater for'heatin 4.boiler feed water comprising a vertical .cylindrical4 tank subdivided vertically bypartitions into a plurality vof compartments', means for lsupplying heating. steam at progressively higher pressures tosaid respective'compartments, a cap for the upper end 'of said tank having-vertical partitions corresponding'in position 'to the partitions in said tank and forming compartments in said cap correspondin to the compartments of the tank, each o said. compartments having an outlet for uncondensible gases and an inlet for water to be heated surrounding said gas outlet, means associated with each of said water inlets for distributing the incoming -water'in a curtain of spray surrounding the gas outlet, water outlet connections for the compartments of said tank, Water inlet connections for the compartments of the cap, and an external pipe joining one f said outlet connections Withone of said inlet connections, and means therein for increasing the cally by partitions into a plurality of com' partfments, means for supplying heating steam at progressively .higher pressures to said respective compartments, and means for passingboiler reed Water successively through said compartments, each ofsaid.

compartments having an outlet near the top thereof for uncoiideiisible gases 'and an inlet for ivater to be heated surrounding said gas outlet, and means associated with each of said water inlets-for distributing the incomingr Water iii a curtain of spray surrounding the gas outlet. A i

4. In a steam generating system, a. heater for heating boiler feed lwater comprising a. vertical cylindrical tank' subdivided vertically by partitions into a plurality of compartments, means' for supplying heating steam at progressively higher pressures to said respectivecompartments, eacli'or` said compartments having an `outlet near the top thereof for uncondensible gases and an inlet for water to be heated surroundin said gas outlet, means associated -With eac of said water inlets for -distributingthe incoming water in a curtain of spray surrounding the gas outlet, and means comprising a series- 'flow externalpipe arranged between two of said compartments which are at progressive-- ly higher pressures, and'means therein or increasing the pressure on the'boiler feed Water to substantially the pressure of the compartment having the higher pressure.

5. In a steam generatingfsystem, a heater for heating boiler feed Water comprising a vertical .cylindrical tank subdivided vertically by partitions in'to afpluralityof compartments, means for supplying heatiii g steam at progressively liighoi pressures to said respective compartments, cach ot'lsaid compartments having an outlet near the .top thereof :for uncondensible gases and an inlet for water to lic' heated surrounding said gas outlet, means associated with each of said Water inlets for distiibutingtlie incoming Water in a curtain of spray surrounding the gas outlet, and means' comprising a series-flow eX- tei-nal pipe arranged between two of said compartments which are at progressively higher pressures, and a pump therein for increasing the pressure on-the boiler eed water to'substantially the pressure of the compartment having the higher pressure.

In testimony whereof I affix my signature.

RUSSELL. o. JONES.