US2048759A - Heat recovery method and means - Google Patents

Description

M. WA STOUT July 2s, 1936.

HEAT RECOVERY METHOD AND MEANS Filed March 6, 1933 3 Sheets-Sheet 1 fille' IIII'II IlIII.

NIN i INVENTOR.

J1 ly 28, 1936. M. w. sToUT HEAT RECOVERY METHOD AND MEANS 3 Sheets-Sheet 2 INVENTOR.

Filed March 6, 1933 July 28, 1936. M. W STOUT 2,048,759

HEAT RECOVERY METHOD AND MEANS Filed March 6, 1933 3 Sheets-Sheet 3 INVEN TOR.

Patented July 28, 1936 mais ` 2,048,759 HEAT \RECOVERY METHOD ANDMEANS A Minor W. Stout, Kansas City, Mo.

Application March 6, 1933, Serial No. 659,729 12 Claims. (ci. 1.22".-396) This invention relates to improvements in heat recovery methods and means, and more particularly to a system for the recovery of the heat content of steam and water from steam boilers,

such that, following cleaning or inspection `of the boiler, a substantial part of the original heat content may be restored to a fresh supply of boiler feed water. The system to be described by Way of exemplifying the invention, illustrates a preferred and improved practice in the recovery of heat from locomotive boiler blowoff iiuids.

As conducing to a better understanding of the advantages of the method and apparatus identi-V fied with the present system, it may be noted that the heretofore prevailing practice of washing and cleaning locomotives upon arrival thereof in a roundhouse after a run, consists, first, in blowing 01T the boiler water, containing a substantial amount of mineral; this water existing at a temperature of the order of 360 F., corresponding say, to pounds gauge pressure. The blowoff operation usually takes place by connection of the locomotive boiler, say to a blowoif header, and thence into a blowoff tank. At usual temperature and pressure a great deal of ash steam is usually given off, connection being made from the blowo header, according to prevailing practice, to a nozzle in the feed water storage tank, so that the resulting flash steam is utilized in some measure, to heat the boiler feed Water which may be supplied from a suitable softener or from the mains. After completion of the blowoff operation, the water taken from the blowoff storage tank is cooled down with fresh Water, say to a temperature of 120-130 degrees F. This Water is forced as by a steam driven pump, at about 100 pounds pressure, into the mud drum of the locomotive. After the mud and scale is there loosened up and removed, the washout water is run to the sewers. Water from a clean Water storage tank is then delivered to the clean locomotive boiler, at say 180 degrees temperature. The locomotive is then again ready to be red, and

after some little period of time is enabled again change of conditions that, at the start of the resteaming operation, the same locomotive will contain say 3,500 gallons of fresh feed water at a temperature of not tov exceed 180 degrees. The foregoing operation, while subject of course to the varying practices of different railroads, serves to typify the heat' Waste normally incident to the practice prevailing before the advent of the present system.

An object of the invention may thus be generally stated as the improvement of facilities for reclaiming heat from blowoff boiler uids, resulting in a greater recovery of the heat content of boiler drainage and flash steam, than is possible through the use of the prevailing facilities for this purpose.

Another object of the invention is attained in an improved combination of blow-olf storage tanks and interconnecting lines, with heat recovery devices adapted respectively for the transfer' of heat. from the blowoif water to the boiler feed water, and for the transfer of the heat units of blowoif steam, to a fresh Water supply utilized for refilling the boiler, for example, after cleaning or inspection.. Y

Still further objects are attained in an interconnected or functionally related aggroupment of apparatus, suchl that asubstantial part of the boiler'blowoi water and steam may be temporarily stored under a substantial pressure; in the utilization of improved heat exchanging facilities, such that` a portion of the blow-olf Water and/or steam may be conducted in heat transferring relation to a supply of fresh make-up water; further in a combination of apparatus such that all or a portion of the flash steam from the blowoi uid is caused to deliver a substantial'part of its heat content for preheating a supply of clean boiler feed Water.

Numerous other objects are attained in substantial improvements in the individual items of equipmentutilized in the combination or system; among these may be mentioned an improved reservoir for receiving the incoming liquid in a heat exchanger of counterflow or zigzag type; an improved arrangement forv circulating liquid within the tubes of such a heat exchanger; an improved strainer for use in connection with the pumps, or some thereof, of the present system. It is t0 be noted, however, that certain of the embodiments of these objects are perhaps applicable to apparatus other than the units of the present system. y

The foregoing and many additional objects will appear from the following detailed description of the items of apparatus going to make up the system, and the technique involved in their use, considered in connection with the accompanying drawings, in which:

Fig. 1 is an elevation illustrating in part diagrammatically, the different items of apparatus employed in an existing system, according to the present invention, certain items of the apparatus being illustrated in vertical sectional elevation to disclose parts internally thereof; Fig. 2 is a side elevation of a heat exchanger of a type preferably employed in connection with the system of the present invention; Fig. 3 is a vertical section along line 3-3 of Fig. 2; Fig.- 4 is a horizontal section along line 4 4 of Fig. 1, being taken through a heater head or steam water heating device, as utilized according to the present invention; Fig. 5 is a section along line 5-5 of Fig. 1; Fig. 6 is a longitudinal sectional elevation of a steam ejector device employed in the present system; Fig. 7 is a plan view, and Fig. 8 is a side elevation, of a preferred form of strainer such as utilized in connection with the pump intake of portions of the system.

The invention is `herein described with reference to an installation of heat-recovery and transfer means, in a railroad roundhouse, as there utilized for reclaiming heat from the drainage and blowing-off of locomotive boilers. My preference is to provide, say along the wall of the roundhouse, a plurality of headers whereby the heat recovery plant may be installed in such location as not to interfere with the trackage and other usual roundhouse equipment and floor space. There is accordingly provided a blowoff header I 0, a washout header I2, and a Water header I4, for boiler fillup water. Each of these headers is in the nature of a manifold, which may be dead-ended at its termini. Each of the headers is provided with a suitable flexible connection (not shown) adjacent each of the locomotive stall tracks of the roundhouse. This arrangement permits a fluid connection or a plurality thereof to be made from any locomotive on any of the roundhouse tracks, into any or all of the headers, as may be desired.

The blowoif header or pipe I0 is directly connected, as by a pipe line I6, through a valve I8, to an accumulator tank 20 of substantial size, and pressure resistant; a valved branch pipe 22 also serving to connect the line I6, through a valve 24, to a blowoff water storage tank 26.

The tank 26 is provided internally with a discharge line '28, having its inlet 30 submerged, but kept near the upper surface of the liquid within the tank as by a float 32. The sections of pipe constituting the line 28 are jointedly connected, as through flexible or swing joints 34, a detail of a joint suitable for this purpose being shown in section in Fig. 5.

The line 28 in passing out of tank 26, serves to direct the flow of water into the uppermost pass of a heat exchanger, indicated generally at 36. The details of an exchanger of a suitable type are set forth in my copending application of Serial No. 561,132, filed September 4, 1931, wherein the exchanger is described and claimed. It is thought sufficient for purposes of present description to note that the exchanger 36 comprises a series of convergently and divergently directed trough elements 38, which, however, may be closed completely so as to constitute pipes rather than troughs. The elements 38 thus arranged in zigzag manner, are closed at their ends by headers 40, extending between and interconnecting which are a plurality of tubes 42 (see Fig. 3). Each of the trough elements is provided with a discharge opening at its lowermost e`nd so that the tubes and headers on the one hand, and the conduits or troughs 38 exteriorly thereof, on the other hand, constitute two complete contiguous circulatory systems operating as a liquid heat exchanging device of countercurrent type. In the system presently illustrated the uppermost element 38 is supplied from the discharge end of the pipe 28, the flow therefrom being crosswise of and from top to bottom of the exchanger. The system of tubes 42 and headers 40 is connected into a fresh water line 44, preferably supplied from a water-softening device of any usual form.

As will appear from Fig. 2, it is my preference to provide the exchanger 36 with a water box |00, shown as disposed at the upper end of the exchanger, and in the inlet portion of the system of troughs 38. The water box |00 may consist of a structure of rectangular transverse section, formed of sheet metal provided with side elements of tapering height, and supported at one end as shown, by a bracket lill, and connected for support at the opposite end to the uppermost header 40. The inlet pipe 28 is preferably directed into one or the high end of the water box |00. The box is provided with a baiile element extending transversely thereof and indicated at |02, the baille being disposed at an angle say of 30 degrees to the horizontal. The baie and box serve to reduce the velocity of flow from the pipe 28 and thus tend to promote settling or precipitation of any solids suspended in the inflowing water or other liquid. The box |00 is provided with an outlet or discharge opening I03 closely overlying the upper end of the uppermost trough 38 of the exchanger.

A further improvement in the exchanger'36, over the form in which it is described in my copending application, Serial No. 561,132, above referred to, consists in the addition, within each, or at least certain, of the tube elements of the exchanger, of a spiral thimble structure indicated generally at |04. The location and form of the spiral thimbles best appears in Fig. 2, each thimble consisting of a strip of metal, originally at in form and of suitable gauge, preferably of a non-corrosive material. Each thimble |04 is formed by twisting such a strip so as to produce thereof a spiral element, the outside dimensions of which correspond substantially to the inside diameter of the tube in which the thimble is disposed. At one, say the uppermost end of the tube in which the thimble is disposed, is provided an L shaped extension |05, the length of this extension so exceeding the diameter of the tube containing the thimble, that the thimble is positioned against displacement resulting from ilow of liquid through the tube. The thimble serves to produce a rotary motion of the uid as it proceedsv through the tube, and serves definitely to prevent stratification of the liquid within the tubes. By thus subjecting the liquid content of the tubes to a slow rotary, or perhaps a whirling motion, depending upon velocity, a given length of tubing will serve with greatly increased efliciency as a heat transferring agency.

A convenient mode of installation is to locate the heat exchanger 36 above a washout water storage tank 46. The tank 46 is provided internally with a standpipe or overflow pipe 48, which is by preference readily removable from the tank 46 for purposes of cleaning; The inlet to pipe 49 is kept appreciably above the bottom of the tank, so that the lowermost portion of. the tank may provide a trap or reservoir for scale and foreign matter which may precipitate in the tank 46, the capacity of which is such as to require removal of accumulated solids only at wide intervals.

Connected into the upper portion of tank 46, is arr intake pipe 58 directed to a pump 52 discharging into a pipe line 54 directed into the washout header I2. The pump 52 may be of any suitable type, but my preference is to utilize a centrifugal or. other revolving impeller type pump at this point in the system, steam pumps of usual reciprocating type having been found inferior thereto in actual practice. The tank 46 is conveniently disposed as shown by Fig. l, partly below the ground line or floor level, and with the standpipe or overflow i8 somewhat above the intake to pump 52, obviating any difficulty of maintaining the pump 52 in prime.

As a storage reservoir for fresh boiler llup water, there is provided a tank 56, disposed above and communicating with which is a water heater head of steam-contact type, the head being indicated generally at 58 (Fig. 1) and shown in detail in Fig. 4. The construction and arrangement of parts in this device are fully described in Letters Patent No. 1,879,582, issued to this applicant under date of September 27, 1932. Briefly described, this device consists of a casing 66 of open end, flattened cylindrical form, provided with tangentially arranged, opposed steam inlet openings 62. Branch pipes 64 serve, together with a steam line 66, to direct flash steam from the blowoff storage tank 26, to points peripherally and internally of the casing 66. Disposed centrally of the casing 66 is a cluster fitting 68, providing two separate sets of water inlet nozzles 'I0 and 12. A connection T4 is provided from the upper set of nozzles l2, to the header I4, for a purpose hereinafter appearing. The lower set of nozzles 'lil is supplied from a water line 16, directed from the uppermost header 40, and hence from the inner or tube circuit of the heat exchanger. The arrangement of the heater head is such that, as a water supply from either or both of the pipe lines 'I6 and I4 is sprayed upwardly through the steam zone it hits the top of casing 6D and falls back through the same steam zone and out the bottom of casing 66 into fresh llup tank 56. Flash steam entering through the tangential openings 62 gives up its heat content or a substantial part thereof, to the incoming water, which immediately descends by gravity, through the lower open end of the heater head 58, and thus into the fresh feed water storage tank 56. Water to be utilized for boiler refilling purposes is withdrawn from the tank 56 as through a jointed line 'i8 provided with flexible joints 34 which may be similar to the swing joints in the line 28. As in the blowoff water storage tank 26, the inlet to line 'I8 is kept submerged, and spaced slightly from the top of the water level in tank 56, as by a float 8B, to secure the hottest and cleanest water available. The line 'I8 is directed outwardly through the wall of tank 56, thence to the inlet of a centrifugal pump, or other suitable displacement means, indicated at 82. The outlet from pump 82 is connected as by a line 84, through a steam ejector 86, thence into the feed water header I4. The fitting 86 consists of an ejector nozzle, provided preferably with a T- shaped body, the lateral branch of which is connected as through a valve 88 into the upper portion of the accumulator tankv 20, for a purpose more fully hereinafter appearing. A check valve 89' is also desirably disposedbetween the accumulator 28 and the valve 88.

The details of structure and the. internal arrangement of parts of a presentlyr preferred formv of ejector such as 86, best appear in Fig. 6,v wherein the fresh water pipe 84 is shownas con-r to permit the entrance of steam from the'cham- I ber within the body, steam being supplied: there-l to through the pipe, |08 from the accumulator.. An auxiliary fitting H3 forms a prolongation of the Venturi element I I2, the members I I2 and H3. being telescopically connected and detachably carried by the body as by threaded cap screws. H4. At the outer end of the extension II3 is.v connected a pipe H5, directed into the header I4 above described.

In operation,` as theA fresh water is introduced under pressure to the sleeve |09, the augmented velocity due to the throat portion of the Venturi elements, creates a suction within the inlet end of the Venturi fitting I I2 which is open to receive the steam from theY accumulator 20. The steam-v receiving portions of the structure are thus subjected to a somewhat reduced pressure or suction, with the eifect that the fresh. water becomesE mixed with the flash steam from the accumulator 2G, and serves to heat the fresh Water before introduction thereof to the header I4. The type of steam ejector here described, is available to the trade for numerous other uses, and does not, of itself, constitute a part of the present invention. Hence, no claim is made tothe device except in combination with other items of ap-Y paratus herein described.

It will be understood that. other valves may be. interposed inthe several headers, water lines and. steam lines, at desired locations; it is mypreference, for example, to locate a valve 9U in a. j

a considerable amount of foreign matter or sludge .i

in suspension, it is my preference tol provide thev inlet to the pump 52 with a strainer or the like,

which will prevent the entrancev of solids to` the y pump and to the line into the header I2. For'. this purpose I have devised a strainer shown in. preferred form in Figs. 7 and 8. This structure. may be supported within the tank 46 as by asuitable bracket I20 carried by a wall of the tank. TheV strainer properv consists of a base plate I2 I which may be bolted or otherwiseafilxed to the bracket |26. The plate I2I is provided with recesses, say of circular sectiorn'to receive: in spaced relation a plurality of vertically dis.- posed pins or rods I22. These. rodsl are,4 in thel example shown, arranged in the form oi?` a square,` with the rods so spaced as to restrict the size ofi solid particles which may pass therebetween. The relation of the external diameter of pins I 22 and the recesses therefor in the base plate I2I is such that the pins may be driven into the rel their entire exposed length.

' The intake fitting for the pump 52 is shown at |24 as consisting of an elbow turned soas to present its opening' parallel to the plate |2I, and .spaced thereabove. The elbow is carried by the intake pipe' |25 connected to the pump 52.

` fAn advantage of the present structure is found inthe ease of cleaning the strainer of accumulated solids. It will appear that the water has access to the intakerfrom all sides of the pinscreen structure, and hence any entrained or occl-uded solids will be trapped against the ext'erior surfaces 'of the pins.` After a period of use, or when the accumulation of solids necessitates their removal, an ordinary garden rake may be employed, andthe foreign material .removedfrom along the pins either by direct lateral disengagement of the material, vor by raking. it upward along the pins and away from the tops thereof. The latter practice has been found particularly advantageous where the entrained or filtered material consists of fibrous or like substances, it being understood that. the described pin-type strainer may be advantageously utilized at other points in the present system, or in connection with pumps or pipe lines handling a great variety of solid-containing liquids, and emplcyed with other apparatus.

It will be.v understood that the foregoing description2 of parts intentionally komits certain details of structure of lesser importance and which lwill suggest themselves to'those skilled inth'e'art.- For example, such of the piping as desired, and certain itemsV of equipment employedfo-rstorage or heat exchanging purposes, may be heat insulated. Sludge drains (not shown) may also be provided in the tanks 20, 26, and 56.A Obviously also the space relation prevailing between the different items of apparatus as depicted in Fig. 1, is not necessarily adhered to in practice. The arrangement of parts may obviously be employed in l`accordance, with the space conditions prevailing in a particular roundhouse, or a stationary boiler installation.

According to the practice of the present invention, when a locomotive is brought into the roundhouse, containing, say 3000 gallons of water at'say 360 F., or 150 pounds steam pressure, the locomotive is connected into the blow out header l0, valves24 and 88 are closed, and valve I8 opened, so that a part of the-blowoff water and s'teamare `discharged intovthe accumulator 28. The accumulator is so'proportioned that it will accommodate enough concentrate to secure a favorable heat balance, at a pressure say of 40 pounds. The remainder of the boiler water with its corresponding heat content, at this time remains inthe locomotive. Valve |8 is no-w closed so that the necessary heat is held in the accumulator 28, at a gauge pressure, say'of 40 pounds, corresponding to 287 F. Valve 24 is then opened, so as to connect the header ID, through line,22, -with the blowoff water storage tank 26,

4and the remainder Yof the locomotive sludge water at say 40 pounds pressure, is conducted into the'tank 26. The substantial amount of flash steam which results from the entrance of the blowoff water into tank 26, is conducted through line 66 and thence into the tangential steam openings 62 of the heater head 58. During this time fresh water, say at 4080 F., proceeding fromthe softener or other supply, is being .conducted through the line 44, thence through the tube and header system of the ex-v changer 36, thence outwardly through the pipe line 'l5 to one or other lower set of the nozzles, such as 18, of the heater head 58. It will appear that the water in line 16, prior to its entrance to the heater head, will have been heated substantially by conduction in the exchanger, due to the countercurrent flow of hot water from the tank 26.

Water from the` nozzles I8 and/or 12 of the heater head, is brought into contact with the whirling jets of flash steam, which augment the heat content of the fresh water supply, the steam-treated water being delivered by gravity into the fresh-water tank 55, at a temperature ofthe order of 140-180 degrees F.

As the blowoif water from tank 26 is conducted through the line 28, and thence into the heat exchanger 36, preferably the outer elements or circuit thereof, the blowoff water is cooled to a temperature of 130 degrees F. or lower, this cooling operation, aswill have been observed, serving to heat up the incoming fresh water in conduits 44, 48, and 42, enroute to the heater head. This cooled blowoil' water may be delivered by gravity from the exchanger 36, directly into the washout water storage tank 46 where it is available through pump 56, line 54 and the washout header 2, for purposes of cleaning the locomotive, interiorly` and exteriorly. At this temperature the water may be safely handled through a hose or other exible conduit for washing purposes. As will have appeared from the description of structure, the overow pipe 48 from the washout. storage tank 46, serves automatically to remove Aany blowoff water in excess of actual requirements for washing purposes. v

Since a substantial cooling of the blowolfwashing water occurs in the exchanger, a substantial precipitation of mineral content will take place in theV tank 46, which thus serves as a settling basin. The location of pipes 48 and 50 above the bottom of the tank, permits a periodic removal of sludge or precipitate, and entraps these solid materials, preventing any further circulation thereof through the system.

vAfter thorough cleaning of the locomotive by means of the wash water from the tank 46, fresh feed water for refilling the boiler is pumped from the storage tank through line '|8, pump 82 and line 84 into the feed water header I4, thence to the locomotive boiler. It will be seen that in traversing this line, water from tank 55 proceeds through the steam ejector 86, a steam connection being made thereto from the accumulator by opening the valve 88. Flash steam from the accumulator at about 40 pounds pressure immediately mixes with the fresh feed water in the inductor, en route to the locomotive boiler. This permits carrying a pressure in the feed water line, and results in the introduction of the fresh refillv water at a temperature substantially above thepboiling point, say in the range of 220 to 250 degrees F., and at a pressure considerably above atmospheric. A corresponding heat con- :tent vof the .accumulator fluid, is thus delivered to the locomotive.

By thus filling the locomotive `boiler with Water ata temperature say of the order of 250 degrees F., instead of at the prevailing temperature, under the older practice, of 180 degrees F.., the steaming-up time heretofore required, is consid- `erably reduced, as is the amountof fuel required `to raise the boiler to a steaming condition.

It will have been observed from vthe foregoing that a distinct saving is effected in roundhouse practice, in that, without any extraneous source of heat, a locomotive boiler after cleaning and relling, possesses a heat content prior to resteaming represented by, say `3500 gallons `of water at a temperature. of 220 to 250 degrees fF.; undef' the older practice, due to undue waste and failure properly to reclaim the heat content of -blowoff Water, the same amount, say of 3500 gallons of water, existed prior to re-steaming, at a temperature of not to exceed 180 degrees F.

It will also have been observed from the foregoing description that no extraneous source of heat need be employed to obtain the higher temperature of the incoming boiler feed water. The relatively larger amount of reclaimed heat is due in part to the confinement and maintenance of the greater part of the original steam pressure, whereby there is conserved a substantial part of the llatent Aheat of vaporization. A major factor in heat .conservation consists in confining the flash steam within the sludge body with little loss, entirely within a closed system, at a pressure above atmospheric. The .heat saving incident to the .presentzmethod and apparatus, is also traceable in large measure to the use of the very em- :ient counterflow heat exchanging device 36. The necessary reduction of temperature Aof a certain amount of the water for purposes of washing, is accomplished in the exchanger without any material `waste of heat; this heat being utilized in, and imparted to the fresh water or boiler feed supply in the tank A56. The use of .a steam and .water contact device, such as the heater head 58 of the .present example, also serves much more efficiently than under prevailing practices, to transfer the heatcontent of the flash steam from tank .26, to the fresh water supply utilized for rell.

While the description has been particularized with respect to a method and apparatus for reclaiming the 'heat of locomotive boiler fluids, the principles of the present invention -areapplicable equally, with or without minor changes, to stationary steam boilers, heating plants utilizing steam, steam generators, and other analogous equipment. The present detailed description of an illustrative embodiment of the invention should not be understood in a limiting sense,rsince numerous changes may be made in the parts, their combinations, and the practices employed in connection therewith, without departing from the full intended scope of the invention as defined by the appended claims.

claim:

l. VThe herein described method of reclaiming heat from a steam boiler incident to blowoff and replacement of the boiler water supply, which consists in heating the supply water in three stages, namely, first by circulation countercurrently to a flow of the blowoif water, secondly by admixing a stream of fresh supply water, and a flow of flash steam from the blowoff water, and thereafter injecting steam, at a higher pressure than said flash steam, into the supply water .and in introducing the heated supply water to the boiler.

2. The herein described method of reclaiming heat from a steam boiler, incident to replacement of the boiler Water supply, which consists in blowing off the boiler while under a relatively high pressure, into a steam-water container, and

`at a relatively low pressure in a second such container, in preheating fresh water .by water from the `second container, and in .turbulently admix- Aing streams .of preheated fresh supply Water and flash steam from the said second blowoff water container, out of contact with the body of blowoff water therein, in injecting steam from the :high pressure container to the supply water, and

in adding the steam-treated supply water to the boiler for rell purposes.

:3, The herein described method of reclaiming Yheat from a steam boiler as an incident to boiler washing and replacement of the boiler water supply, which consists in conducting .portions of the blowoff water into separate high and low pressure containers therefor, in cooling a portion of the blowoif water from the low pressure container by conduction of its heat content to a stream of fresh boiler feed Water, in conducting .the cooled blowoff water to a reservoir therefor to effect precipitation of a portion of the mineral content of the blowoff water, and thereafter utilizing the water from such reservoir for boiler washing purposes, in utilizing the steam from the low pressure container for a second stage of heating of the feed water, and thereafter utilizing the steam from `the .high pressure container as a third stage of heating the feed water. v

4. The herein described method of reclaiming heat from a steam boiler, incident to washing the boiler and replacement of its water supply, which consists in conducting relatively high and -low temperature portions of the boiler blowoff fluid to separate containers therefor, in utilizing a rela' tively low temperature portion of such blowoff uid for boiler washing purposes, in concurrently heating the feed water and cooling the wash fluid, by countercurrent circulation thereof through adjacent heat transferring passages, in further heating the feed water from the relatively low temperature fluid, and thereafter in a separatel stage, by contact with the high temperature fluid.

5. The herein described method of reclaiming heat from a steam boiler incident to replacement of the boiler water supply, which consists in segregating and separately confining quantities of the boiler blowoif water and steam, as high and low temperature portions respectively, in utilizing the lower 4temperature portion of the blowoff fluid for heating, lby conduction, a supply of fresh feed water, in further heating the feed water by admixture thereof with flash steam from the said lower temperature portion of blowoff water and in still further heating the feed water by absorption -of the heat `content of the high temperature portion incident to circulation for refill purposes.

6. The herein described method of reclaiming heat from a steam boiler as an incident to replacement of the boiler water supply, which consists in storing under pressure exteriorly of the boiler a substantial part of the boiler blowoff water, vstoring in a second container an additional portion of the blowoff water, in concurrently circulating in separate systems a stream of water from said second blowoff container and a stream of fresh feed water, in subjecting said stream of fresh feed water to a turbulent admixture with flash steam from said second blowoff container,

and in thereafter subjecting the supply of fresh water to a flow of steam from the confined blowoff water, and introducing the supply of steamtreated fresh water to the boiler, under a substantial steam pressure. v

7. In apparatus for reclaiming the heat of drained boiler iiuid, a boiler drain conduit, a tank structure for confining blowoff water and steam under pressure, a connection between said tank structure and said conduit, a fresh feed water conduit, means for preheating the fresh feed water in said conduit, including elements for separately and countercurrently circulating in adjacence thereto a portion of the blowoff water, a storage tank for the preheated feed water, an

.injector having a steam connection to said blowoff pressure tank structure, a water inlet connection to said preheated feed water storage tank, and a discharge conduit for directing the steam treated feed water from the injector to the boiler, for refill purposes.

8. Apparatus for reclaiming heat from drained boiler fluids, including a low pressure container and a high pressure container, each for blowof water and steam, a conduit for fresh feed water, means for circulating the water from said low pressure blowoif container countercurrently and adjacently in heating relation to the flow of fresh feed water in said conduit, means for effecting a further heating stage of the feed water by contact with steam from the low pressure blowo container, a conduit arranged for directing the steam heated feed water, for boiler refill purposes, and means in said conduit for utilizing the heat con- 1 tent of the high pressure container in a subsequent heating stage as the feed water is utilized for refill purposes.

9. Apparatus for reclaiming heat from drained boiler fluids, including a container for receiving blowoif water and steam under pressure, a fresh water conduit for boiler refill purposes, a conduit for separately but adjacently circulating blowoif water countercurrently to the fresh water for preheating the freshboiler feed water while traversing its said conduit, a storage tank for the preheated feed water, a heater of steam-water contact type connected for utilizing a portion of the blowoff steam for heating feed water prior to its introduction to the storage tank, and a steam ejector having its steam supply connected to said blowoif container and being connected in the fresh water conduit beyond the: storage tank, and adapted for the introduction of fresh water to the boiler, under substantial steam pressure.

l0. Apparatus for reclaiming heat from drained boiler fluid, including a pressure container for receiving blowoff water and steam and conning same in three fractions, at low, intermediate and high temperaturaafter their removal fromthe boiler, a fresh watersupply line, means connected into the blowoff container and fresh water line for adjacently circulating separate streams of water therefrom for heating the fresh water supply, by utilization of the low temperature fraction, means for further heating the fresh water supply in a second stage by contact with the intermediate fraction of fiuid from said blowoff container, means forconducting the freshwater from the last said heating means to the boilenlfor refill purposes and a heat transfer device associated with the said conducting means, said device utilizing the said high temperature fraction as aivnal heating stage incident to rell. l1. Apparatus for reclaiming heat from boiler blowoif uids, including avblowoffpressure container, a pressure tank forming a reservoir for Vblowoff water, the container and reservoir being provided with steam spaces, valved conduits from the boiler to said Vcontainer and reservoir, a fresh water supply conduit, a heat exchanger having separate circulatory systems connected respectively to said blowoif reservoir and to said supply conduit, a water heater of steam-water contact type, having a steam connection to the steam space of said blowoff reservoir and a water connection from said heat exchanger, afresh water storage tank communicating with the contact type heater, andv connections for supplying the storage tank therefrom, a steam ejector connected to the steam space of said blowoff pressure container, a conduit from the fresh water storage tank to said ejector, a pump in the last said conduit, and a conduit from said ejector to the bollen-for refill purposes.

l2. Apparatus for reclaiming heat from boiler blowol uids, including a blowoff header, adapted to be connected to the boiler to be drained, a wash out header adapted to be connected to the boiler for washing purposes, a feed water header adapted for the supply of fresh water to a boiler after draining and cleaning thereof, a pipe line from said blcwoff header, provided with two branches, valves in said branches, a pressure accumulator for blowoff water and steam, adapted to contain a substantial portion of the blowoff water from the boiler under treatment, said accumulator being connected to one of the branches of said blowoff pipe, a storage tank for the remaining blowoif water, connected to the other of said branches, the pressure accumulator and storage tank each being closed and having a steam space in its upper portion, a heat exchanger of countercurrent type, characterized by an outer circuit and an innerrcircuit, the outer circuit of the exchanger being connected to the water-containing part of said blowoff water storage tank, a fresh water supply conduit connected to the inner circuit ofthe exchanger, a water heater of steam-water contact typey a water connection to said heat-er from the inner circuit of said heat exchanger, a steam connection to said heater from the steam space of the blowoif water storagetank, a fresh water storage tank and a fresh water connection therefrom to said heater, means including a pump connecting the freshwater storage tank to the feed water header, a settling reservoir for blowoif water, having a supply connection to the outer circuit of saidl heat exchanger,`means including a pump for delivering water under pressure from said settling reservoir into-the washout header, for boiler washing purposes, and a steam ejector, having a steam connection with the steam space of the blowoif pressure accumulator and connected with the fresh water storage tank through the -pump and associatedmeans first'aforesaid, the ejector being further provided with an outlet connectionto the first said feed water header.

f MINOR W. STOUT. l

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