Heat-exchange evaporator apparatus

Jan. 21, 1958

G. ILUNE

2,820,437

HEAT-EXCHANGE EVAPORATOR APPARATUS

Filed Nov. 24, 1953

Sheets-Sheet 1

<img file="US2820437A_D0001.tif" />

Jan. 21,1958 g, ilune 2,820,437

HEAT-EXCHANGE EVAPORATOR APPARATUS Filed Nov. 24, 1953 2 Sheets-Sheet 2

Fic.2.

<img file="US2820437A_D0002.tif" />

United States Patent Office

2,820,437

Patented Jan. 21, 1958

2,820,437

HEAT-EXCHANGE EVAPORATOR APPARATUS 5 Georges Ilune, Paris, France

Application November 24,1953, Serial No. 394,121

Claims priority, application France November 24,1952 ₁₀5 Claims. (Cl. 122—33)

The present invention relates to heat-exchange-evapora- 15 tor apparatus, that is to say apparatus adapted to generate steam or the vapour of some other liquid by the use of a heating medium (intermediate fluid) delivered from some suitable type of heat generator.

It is the object of the invention to provide exchange- 20 evaporator apparatus wherein the liquid to be evaporated (usually water) is propelled through the apparatus with a high flow velocity along or across tubes conveying the heating fluid, without requiring the costly production of any external force to produce the displacement of the 25 liquid.

It is another object of the invention to provide exchange-evaporator apparatus wherein the exchange of heat between the heater fluid and the liquid to be vaporized will be highly uniform, and one which will 30 instantaneously generate dry vapour at high pressures at a controllable rate.

A further object of the invention is the provision of an exchange-evaporator unit all the external components of which may be readily dismantled in order to uncover 35 both ends of the tubing circulating the heater fluid and the liquid to be vaporized, for purposes of cleaning and repair and other servicing operations.

The above and further objects, features and advantages of the invention will appear from the ensuing description 40 made with reference to the accompanying drawings, given by way of illustration but not of limitation, wherein:

Fig. 1 is a view partly in elevation and partly in vertical section illustrating one practical embodiment of the invention; and

Fig. 2 is a cross section on the line 2—2 of Fig. 1.

The apparatus shown comprises a vertically extending central tube 1 for the intake of heater fluid, said tube being provided at its lower or inlet end with a flange 2 or other suitable connector and having its upper end sealed with an end plate 3 preferably though not necessarily of ^Jthe domed construction shown. Mounted within tube 1 are a plurality of tubes 4 (Fig. 2) the upper ends of which project through end plate 3 and are secured thereto as by welding or expansion. The lower ends of tubes 4 extend -_rthrough the wall of the tube 1 and are secured thereto as by welding or expansion, and project into an outlet chamber 5 provided with a connector flange 6. The tubes 4 have their lower ends above the point where they are led out through the tube wall of tube 1, formed with ex- _aopansion bends as illustrated at 7.

The tube 1 adjacent its top is formed with apertures 8 for connection therewith of corresponding tubes 9. The tubes 9 extend vertically downwards and have their lower ends projecting through an annular plate 10 into a cham- ₆₅her 11 having a number of apertures such as 12 formed in its wall for connection through headers 13 to a discharge conduit 14.

The chamber 11 comprises the space defined between annular plate 10 in which the lower ends of tubes 9 are secured through any suitable means capable of providing a good seal, and a removably mounted plate 15 secured as by bolts (not shown) over the flange 16 of a skirt portion 17 extending downwardly from an outer underflange 18, said underflange being bolted to an upper flange 19 formed at the base of a bell member or casing 20. Retained between flanges 18 and 19 is the annular plate 10. As shown, the removable plate 15 is likewise bolted to the lower surface of a flange 21 extending around the lower end of a smaller skirt 22 surrounding and welded to the tubular body 1 for reinforcing purposes.

The fixed bell-member 20 is fitted with a steam pressure-gauge connection 23 and two water-level connections 24.

The liquid to be vaporized, e. g. water, enters through a conduit 25 provided with a connector flange 26 at its lower end, the conduit 25 extending upwards into the tubular body 1 and having its upper end led out through the wall of said body just above the annular plate 10. The outer upper end of conduit 25 opens into a movable bell member 27 surrounding the tubes 9, the vertical dimension of the movable bell 27 being so predetermined that, when said bell is allowed to rest through suitable bosses or the like such as 28 depending from its upper end surface, upon the end or top plate 3 of tubular body 1, a gap 29 will be present between the lower end of the bell 27 and the upper surface of annular plate 10, to provide communication between the interior of the movable bell and the annular space 11 present between the fixed bell 20 and the movable bell 27. It should be noted however that the bell member 27 is provided with a baffle plate 32 adjacent the outlet opening of conduit 25 in order to eliminate the effect of back pressure created by the discharge of liquid out of conduit 25 and prevent said liquid from flowing directly into the annular space 11. The bell member 27 at its upper end is formed with pressure-equalizing apertures 33 for equalizing the steam pressures in the two bell members 20 and 27.

The interior of movable bell member 27 further communicates with the space 31 through apertures 34 formed slightly below the level of the lower one of the waterlevel take-off connections 24.

To facilitate assembly, the annular plate 10 may be provided with securing lugs 35 projecting radially beyond the flanges 18 and 19.

As already stated, the heating fluid is delivered into the apparatus through tube 1, while the liquid (e. g. water) to be vaporized is delivered through the conduit 25, and the apparatus operates as follows:

The heater fluid rises through tube 1, issues out of the tube through the apertures 8 and flows back through tubes 9 into chamber 11, whence it is returned to the heat generator through the apertures 12, headers 13 and discharge pipe 14.

The water entering through conduit 25 issues out therefrom above the level or annular plate 19 into the space defined between tube 1 and movable bell 27 which space houses the tubes 9. The bubbles of steam formed in the water on contact thereof with the surface of tubes 9 rise and carry the water up with them, so that the water level in movable bell 27 will be higher than that in fixed bell 20, i. e. within the space 31 defined between the two bells. In this way a circulation is created with the water flowing downwards through space 31 and upwards through bell 27. Such circulation is made possible owing to the presence of the space 29 and of the apertures 34. It is to be noted that the arrangement described, in that it increases the counter-flow velocity of the water, results in an increase of the thermal exchange factor.

The steam separating from the liquid water at the free surface of the latter rises up into the top of the bell 27 while still remaining in contact with the tubular body 1 and tubes 9 which are hotter than the steam, and then flows down through the tubes 4 surrounded by the heater

2,820,437 fluid which is hotter than the steam generated, and thereupon passes into the steam outlet chamber 5 whence it is discharged for utilization.

In order to limit the upward rise of the movable bell 27, the outer or fixed bell is provided with a limiting stop or boss 36.

It will be understood that various modifications may be made in the structural details disclosed without exceeding the scope of the present invention.