DE1089787B - Heat exchange device in which heat is transferred from a medium to be cooled with the interposition of an evaporating transfer fluid to a coolant - Google Patents

Description

GERMAN

The invention relates to a heat exchange device in which heat from a to be cooled Means is transferred to a coolant with the interposition of a transfer liquid and as Transfer liquid a liquid is used that is at the temperature of the medium to be cooled evaporates.

In the known heat exchange devices, such as the known steam condensers, the latent heat of the vapor through the use of large amounts of a cooling liquid, e.g. B. Water, while in other heat exchange devices the heat exchange is by direct Contact or mixing takes place.

It is also the case with heat exchangers in which one medium is cooled by another medium with the interposition of a transfer fluid, known to use as a transmission fluid such that at the temperature of the to be cooled Evaporated by means. In the case of heat exchangers, an annular cavity was provided for this purpose through which the transfer medium flows, and the cavity between the two heat exchange means arranged through flowing lines. It is also known per se to convey a transmission liquid by means of gas bubbles, the gas to cool after passing through the transmission fluid and again in a closed circuit to bring to circulation.

In the known heat exchangers, however, there is the risk that the wall between the to cooling agent and the transmission fluid is heated to excessive temperatures. This disadvantage is to be avoided by the invention. According to the invention this is achieved in that the boiling point the transmission fluid is set to a value slightly below the temperature, to which the agent to be cooled is to be cooled. This takes place with every increase in temperature of the medium to be cooled on the wall between this and the transfer liquid an immediate evaporation of the transfer fluid, and some of the vapor bubbles formed in the process condense on the opposite wall, which is externally flushed with the coolant, and the other part is held by the ascending gas bubbles. In this way, the heat is quickly dissipated from the Wall between the medium to be cooled and the transmission liquid.

The setting of the desired boiling point of the transfer liquid is expedient by adjusting the pressure within which the transmission liquid and gas are contained Circulatory system, it is advantageous to have the means heat exchange device in which Warmth from a medium to be cooled

with the interposition of a

evaporating transfer liquid is transferred to a coolant

Applicant:

Robert James Swinton Smith,

Falsgrave, Scarborough, Yorkshire

(Great Britain)

Representative: Dr. H. Haalck, lawyer,
Hamburg 20, Goernestr. 12th

2

to change the pressure within the the transmission fluid to provide the space contained and the gas in the cooling of entrained transmission fluid to free.

In the jacket of the transmission liquid, the movement of the gas bubbles is advantageous in opposite directions Direction to the flow of the medium to be cooled and made in the same direction with the coolant. The contact zone between the coolant and the jacket walls expediently extends in the direction of flow of the coolant beyond the point at which the medium to be cooled first meets the shell walls. It is also advantageous that the jacket is at the end where the gas bubbles emerge from it, with a gas collecting device and a gas outlet having an expansion tank is connected for the transmission fluid, the .Means for maintaining a constant height of the transmission fluid and a line that carries the transmission fluid in the expansion tank connects to a point near the gas inlets on the jacket. In another version According to the invention, the jacket comes with different coolants at different points along its length in touch. The different coolants are represented by heating oil and cold water, the cold water being in contact with the end of the jacket from which the gas bubbles escape.

009 609/278

3 4

In the drawings there are various execution steam accumulations on the wall of the pipe 1

forming of steam condensers according to the invention could reduce the effectiveness of the heat exchange

application shown schematically. It shows diminish, with also a slight post-condensation

Fig. 1 is a vertical section through a vapor of the transmission liquid on the surface of the man-

condenser, 5 part 4 and the ingress of large amounts of steam into

Fig. 2 shows a horizontal section along the line H-II the expansion tank 5 could occur. It will

of Fig. 1 on an enlarged scale, therefore a transmission liquid used, whose

. Fig. 3 shows as a detail the effect of a boiling point in the boiling point just a little below the temperature

air bubble, the condensing vapor lies.

Figs. 4 and 5 show the use in a direct wir- io The air bubbles and the vapor which are not on the

kenden mixing condenser and wall of the outer jacket condensed, get into

6 shows a device for heating fuel oil to the expansion tank 5. In the expansion tank 5

in addition to steam condensation. means are provided to reduce the liquid that has entered

Steam to be condensed is excreted from the air via an inlet 2 and at least still

in a cylindrical, made of copper or similar 15 to condense part of the vapor so that it

Material existing pipe 1 passed and whose Kon- is not lost with the air. To this end

Densate is passed out through an outlet 3 in order to ent- can the expansion tank 5 with collecting device

neither to run back into the steam boiler nor to be provided with divisions and also a cooling device,

let to be. The tube 1 is of a jacket 4 z. B. a spiral containing a cooling liquid,

surrounded, which contains a transmission liquid and 20 have.

which with its upper end in a compensating It can also the steam at one of the discharge container 5 opens. The jacket 4 is trimmed into the tube 1 from a point remote from the concentration tank 5 Surrounding tube 6 which directs an inlet 7 and one. So z. B. the steam at 13 in the Has outlet 8 for the cooling liquid. As directed in tube 1 and the corresponding steam inlet Fig. 2 is shown, the pipe 1 is on its periphery 25 line between the point 13 and the compensation mit Ribs provided to the heat exchange to container 5 and arranged separately from the tube 1 raise. be thermally insulated. Through this facility will be

Via a pipe 9, and controlled by one, the air-steam bubbles on the cooling surface of the Man valve 11, the lower end of the transfer 4 is subjected to cooling after its supply liquid containing jacket 4 via nozzle 30 heating on the wall of the tube 1 is ended. Lines 12 compressed air supplied, so that air bubbles in The bubbles then rise to the top, pass the the transfer liquid of the jacket 4 in the liquid 14 in the expansion tank 5 and become Fig. 3 shown way rise up. within the collecting tank standing in the liquid

Trapped in the housing 15 during the rise of air bubbles. In this way, the

Jacket 4 is the one on the first exchange surface, d. H. 35 major part of the vapor contained in the air

on the wall of the pipe 1, remaining thin fluid condenses. By increasing the volume of steam in

liquid film due to the heat of the water vapor on the collecting housing 15, the liquid surface

steams and the resulting steam is pressed down with the air of the surface until the ball valve 16 opens

Bladder mixed up. and the air into the pipe 17 and through the opening 18

The steam generated in this way condenses on the counter 40 can flow into the space 19. When the pressure is in overlying wall of the jacket 4, d. H. on which the expansion tank 5 has a certain value Exchange surface, which has extends from the through to the outside, opens a spring-loaded tube 6 conducted cold water cooling liquid cooled the valve 21, and air escapes together with a will. In this way, the steam in the pipe 1 is cooled down by a certain amount of liquid steam and condenses, and the conduit 22 from the steam. This air can now be used for the purpose of excretion conducted heat is almost completely cooled by that in that of the remaining steam and then Cold water located in the outer pipe 6 is compressed and returned to the inlet pipe 9 took. or to be discharged. When the air is back in

By using a transfer fluid to be recirculated, it is not the pressure prevailing in the jacket 4 is absolutely necessary for the entire transfer conditions to be removed at a temperature below 100 ° C, because although the temperature in it, z. B. at 70 to 80 ° C, boils, will be excreted in the remaining vapor, is it constant contact with the transmission fluid, the highest possible recovery of fluid, standing pipe 1 kept at this temperature. Any- from an economic point of view, Licher tendency of the tube 1 to a higher temperature 55 is desirable.

The recovered liquid is counteracted in an evaporation of transfer liquid. In this way the condensation surface of the line 24 is in pressure equalization with the system, pipe 1 is kept at a temperature at which and from which the liquid in the equalization the vapor quickly condenses, and independently of the 60 container 5 flows as soon as the liquid level in it is so rapid with which the vapor condensation drops that a ball valve 25 is actuated,
follows, the heat supplied to the pipe 1 will never increase its temperature to indicate the prevailing temperature in the system. The lower the boiling pressure, a pressure gauge 26 can be provided, the colder it becomes. The valve 21 can be adjustable, so that the wall of the pipe 1 is held and so that the pressure is kept at a desired value, the more effective the condensation of the steam. can be. Adjusting the pressure can, if the temperature difference between the minimum within a limited range, as a condensation point of the vapor and the boiling point means for changing the boiling point of the transfer liquid, then transfer liquid could be used, whereby the transfer liquid could be used boil too much, and 70 appropriate choice of liquid an adequate one

large range can be achieved, which is used to change the operating conditions of the capacitor sufficient.

Further control of the operating conditions of the capacitor can be achieved in that the amount of air flowing through the jacket 4 is regulated by the valve 11, and a regular one Flow of the cooling liquid in one direction is ensured that the pipe 27 the transfer fluid from the expansion tank 5 to one in the immediate vicinity of the nozzle lines 12 lying point in the jacket 4 leads. Some or all of the heat exchange surfaces or pipe walls can be corrugated or ribbed to increase heat exchange. The ball valve 16 can be achieved by the arrangement of a liquid-retaining collection system in the lower part of the tube 17 can be replaced. Any form of cooling device can be in or around the expansion tank 5 can be arranged around.

The agent to be cooled does not need to be passed through the centrally arranged tube 1 of the device but can be contained in the outermost tube 6 while the cooling liquid passes through the centrally located pipe 1 flows. In this case, if the medium to be cooled is a liquid, also omit the outer tube and one consisting only of a jacket and a coolant tube The cooling unit can be immersed in the liquid to be cooled. Such an arrangement is shown in Fig. 4, which schematically shows a direct-acting mixed steam condenser.

To cool the water into which the steam is injected for condensation, a Heat exchange device immersed in the water. The outer surface of this device is covered by a Sheath 31 is formed for the transmission fluid, which has a feed line 32 for the transmission fluid and a feed line 33 for compressed air. The cooling liquid, e.g. B. water, circulates in the opposite direction the direction of air and transmission fluid in a tube 34 within the shell 31 and flows through a coaxial central outlet tube 35 from. The expansion tank and details of the arrangement can be executed according to FIG. 1 or, as described above, modified accordingly be.

Fig. 5 shows a further practical embodiment. Here is the lower cone of the mixing tube as Cooling unit formed and arranged so that the cooling through the transfer liquid surface takes place on the inside of the mixing tube cone and a direct cooling of the in the surrounding container located water is achieved by the circuit of the cooling liquid in the outermost tube.

The jacket 36 contains the transmission liquid supplied through a conduit 37 while through a line 38 of air is blown into the jacket 36. Air and transfer liquid vapor are passed through a line 39 is passed into an expansion tank 41 of the type described. The cooling liquid, e.g. B. cold water, circulates in an outer tube 42 surrounding the jacket 36 and serves as the tube 42 itself is in direct contact with the amount of water to be cooled, additionally as a direct cooling 6g medium.

In the constructions shown in Figs. 4 and 5, the boiling point of the transfer liquid becomes generally be lower than in cases where steam is to be condensed directly as it it is desirable that the amount of liquid with which the vapor is to be mixed is below its boiling point and not to cool the entire amount of the liquid directly, but only that part which comes into direct contact with the cooling surfaces and then mixes with the rest of the liquid will.

Fig. 6 shows a modified device which is used to use heating oil and boiler feed water as coolants to be used and thus preheated by the heat exchange device and that of the steam to use the heat given off for a useful purpose. To accomplish this, it usually is the tube containing the coolant is divided into two separate tubes in which the two cooling liquids circulate. The fuel oil circulates in the pipe 43 furthest away from the expansion tank. This can circulate relatively slowly in order to be heated to the required degree of heat, the tube being provided with ribs in its interior to improve heat transfer can. Here, however, there is less effective condensation of the vapor of the transfer liquid achieved, and there is consequently a tendency that larger amounts of steam get into the expansion tank. For this reason, the part of the shell 4 located in the vicinity of the expansion tank is shown in FIG surrounded by the pipe 44 carrying the second cooling liquid, in which a powerful flow of the boiler feed water circulates to condense as much of the vapor of the transfer liquid as possible. Here, too, ribs or other forms of construction can be used to the greatest possible extent to maintain thermal effectiveness.

Claims (9)

Patent claims: 1. Heat exchange device in which heat is taken from a medium to be cooled Interposition of a transmission fluid is transmitted to a coolant and as a transmission fluid a liquid is used which evaporates at the temperature of the medium to be cooled and is contained in a jacket is, which has substantially parallel walls and between one of the means to be cooled leading line and a line leading the coolant is arranged, with a continuous Gas circulation is maintained in the transmission liquid and the gas after Passing through the transmission liquid and cooled again in a closed circuit Circulation is brought about, characterized in that the boiling point of the transfer liquid is set to a value a little below the temperature to which the to be cooled Medium should be cooled. 2. Heat exchange device according to claim 1, characterized in that means for changing of the pressure are provided within the space containing the transmission fluid. 3. Heat exchange device according to claims 1 and 2, characterized in that the Gas is freed of entrained transmission fluid during cooling. 4. Heat exchange device according to claims 1 to 3, characterized in that in in a manner known per se, ribs or similar heat transfer means on the heat exchange surfaces are appropriate. 5. Heat exchange device according to claims 1 to 4, characterized in that the Movement of the gas bubbles within the jacket (4) in the opposite direction to the flow of the to cooling means and takes place in the same direction with S the flow of the coolant. 6. Heat exchange device according to claim 5, characterized in that the contact zone between the coolant and the jacket walls in the direction of flow of the coolant over the Point also extends at which the agent to be cooled first hits the shell walls. 7. Heat exchange device according to claim 5 or 6, characterized in that the jacket (4) at the end where the gas bubbles emerge from it with a gas trap and an expansion tank (5) having a gas outlet is connected for the transmission fluid, the means for maintaining a constant level of the transmission fluid and a line on has the transfer fluid (14) in the expansion tank with a point near the gas inlets connects to the jacket (4). 8. Heat exchange device according to claim 5, 6 or 7, characterized in that the jacket (4) comes into contact with different coolants at different points along its length. 9. Heat exchange device according to claim 8, characterized in that the different Coolants can be represented by heating oil and cold water, with the cold water with the The end of the jacket (4) is in contact at which the gas bubbles escape. Considered publications:
German Patent No. 857,384;
Swiss Patent No. 280 011;
French Patent No. 948380;
U.S. Patent Nos. 2,316,273, 2,313,087. 1 sheet of drawings © 009 609/278 9.60