JPS59173688A - Heat exchanger and method of operating said exchanger - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to a heat exchanger for cooling a fluid of a given temperature and pressure with a second fluid of a lower temperature and often a higher pressure.

In a conventional shell-and-tube heat exchanger,
The tube section of the heat exchanger consists of a bundle of tubes open at both ends.

At each end, the tubes extend through the heat exchanger and are welded to the tubesheet. The heat exchanger shell completely surrounds the tube bundle. The tubes in the bundle are spaced from each other and from the shell to form the shell-side portion of the heat exchanger.

In a typical heat exchange operation, one of the fluids (liquid or gas) is passed through a tube section of a heat exchanger. Another fluid is forced to pass through the shell section, ie, the section outside the tube, usually in a countercurrent flow path to the fluid flowing through the tube 1 section. An example of a heat exchange operation is the cooling of reaction products from a hydrocarbon cracking furnace. The reaction product is typically gas exiting the cracking furnace at a temperature of about 700-900°C. When the hot gas leaves the furnace,
The hot gas passes through the tube section of the heat exchanger and is cooled by a second fluid (typically water at high pressure that passes through the shell section of the heat exchanger). In operation, some of the heat from the hot gases (reaction products) is transferred to the water through the tube wall. The total efficiency is to raise the temperature of the water, enough to evaporate the water, and to lower the temperature of the gas.

Heat exchangers using the cracking method traps described above have several drawbacks. For example, the deposition of coke on the tube walls causes fouling of the heat exchanger and significantly impairs the efficiency of the heat exchange operation. When coke buildup occurs, the cleaning operation requires manual cleaning inside the tubes as well as lengthy shutdowns of the upstream system. Not only does this cleaning operation have to be carried out frequently, but the heat exchanger may have to be taken out of service for as long as a week. Another problem is the potential for heat exchanger tube damage due to temperature cycling during cleaning. For example, a heat exchanger must be cooled from a slightly higher operating temperature to a slightly lower temperature for a cleaning process, and then brought back up to temperature to resume heat exchange operations.

In an attempt to improve the efficiency of heat exchange operations and/or reduce the mechanical stresses mentioned above, conventional shell-and-tube heat exchangers have been modified in various ways. One of these variations is H,R-Knulle's Problems 111th Exchange
gersin EXhylene Plants”
Chemical Engineering Prog
ress.

Volume 68. A7. C,htly 19
72), pp. 53-56. The heat exchanger has a double tube construction such that the pyrolysis gas flowing through the inner tube is cooled by another fluid flowing through the outer tube surrounding the inner tube.

This type of heat exchanger, as well as many other known heat exchangers, are difficult to clean, requiring scrubbing and substantial shut-down periods. The heat exchanger must also be cooled before cleaning to avoid any damage caused by the temperature cycling system described above.

The heat exchanger of the present invention has several significant advantages over known methods and devices for heat exchange between fluids. For example, a relatively hot fluid can be quickly cooled to a low temperature. This is particularly advantageous in hydrocarbon cranking operations, such as pyrolysis or catalytic cracking reactions, where hot reaction products must be rapidly cooled to eliminate unwanted by-products.

When using the heat exchanger of the present invention, generally about 700·-1
The hot reaction product at a temperature of 000°C is heated in about 0.03 seconds to
It can be cooled to below 0.00 to 700°C.

Another advantage of the heat exchanger of the invention is that it gradually dissipates the relatively high temperatures present in the heat exchanger section in the direction of the head section, which normally operates at lower temperatures and higher pressures. It is an ability. Dissipating heat in this manner eliminates the problem of material degradation that normally occurs in exchangers where a hot zone meets a cold zone. Another advantage is that the time required to clean the heat exchanger of the present invention is much less than the time required for conventional heat exchangers. for example,
Cleaning time generally requires only a few hours. Yet another advantage is that the heat exchanger of the present invention can be cleaned on-line, ie, it does not need to be cooled before cleaning.

This property greatly reduces the possibility of thermal degradation of the tubes and other components of the heat exchanger resulting from the aforementioned temperature cycling system.

The present invention is a heat exchanger for cooling a first fluid at a predetermined temperature and pressure to a second fluid at a lower temperature and higher pressure, the heat exchanger comprising: a head portion including an inlet and an outlet; and a heat exchange portion including a bundle of inner conduits, each inner conduit being open at both ends and extending from said head portion to the heat exchange portion; The heat exchange section further includes a bundle of outer conduits in fluid communication with the inlet for the cryogenic fluid so that the cryogenic fluid can pass through each inner conduit J' (!7). each outer conduit is in fluid communication with the cryogenic fluid outlet and surrounds the portion of the respective inner conduit that is within the heat exchange section and is in fluid communication with the cryogenic fluid outlet and surrounds the portion of the respective inner conduit that is within the heat exchanger section and has an inner surface of the outer conduit and an outer surface of the inner conduit. A channel is formed between the inner conduit and the channel having a means for allowing the cold fluid exiting the inner conduit to flow to the outlet of the head section; It also includes an inlet and an outlet for a fluid, and has a space inside for passing the hot fluid from the inlet to the outlet so that the hot fluid comes into contact with the conduit containing the cold fluid. A temperature regulating zone is provided between the head section and the heat exchange section, and this zone is used to receive a fluid having a temperature lower than that of the hot fluid and a pressure higher than that of the hot fluid. A heat exchanger comprising:
It is in.

The present invention also provides the following steps: passing the hydrocarbon reaction product as a hot fluid through the heat exchanger through the hot fluid inlet; The water is passed through a heat exchanger with an outlet for the cold fluid; the hydrocarbon reaction product is brought into total indirect contact with the water to partially cool the reaction product and evaporate or heat the water; The hydrocarbon reaction product is further cooled by direct contact with water vapor passing through the exchanger; the cooled hydrocarbon reaction product is discharged from the heat exchanger through a hot fluid outlet along with all the water vapor; A method for cooling reaction products from a hydrocarbon racking reactor, comprising: discharging heated water through a cold fluid outlet.

FIG. 1 is a schematic illustration of the heat exchanger of the present invention, showing the flow path of fluid through the heat exchanger during heat exchange operations.

FIG. 2 is a front view, mostly in section, of a particular embodiment of the heat exchanger shown in FIG.

FIG. 3 is a front view, mostly in section, of another embodiment of the heat exchanger shown in FIG.

FIG. 4 is a broken cross section 1 taken along line IV--IV of FIGS. 2 and 3 showing the tube sheet and tube bundle of the heat exchanger.

FIG. 5 is a broken cross-sectional view taken along the line ■-■ in FIGS. 2 and 3, showing a portion of the tube bundle in the heat exchange portion of the heat exchanger and a member supporting the tube bundle. This shows that.

FIG. 6 is a detailed cutaway view of the sealed end of the outer conduit in the tube bundle, showing the inner conduit disposed within the outer conduit and the members within the outer conduit that fully support the inner conduit; It is something.

FIG. 7 is a cross-sectional view taken along the line ■--■ in FIG.

FIG. 8 is a front view, mostly in section, of yet another embodiment of the heat exchanger shown in FIG.

FIG. 9 is a cross-sectional view taken along line IX--IX in FIG. 8, showing the structure of the tube bundle at this location in the heat exchanger.

Referring to these figures, the heat exchanger device of the present invention consists of a head part (10) and a heat exchange part (11).

Referring to all the specific examples shown in FIG.
2) and the second tube sea) (13). Tube Sea) (12) is relatively thin, e.g.
It is a structure of the 10th category. However, tube sheet (1
3) is generally constructed of thicker material, for example about 10 to 35 strips of material. The thickness of each tubesheet depends primarily on the pressure differential that exists on each side of the tubesheet. (13) is subject to high differential pressure during heat exchange operations, so tubesies)
(12) Usually constructed of a thicker material.

The head part (10) is divided into two separate chambers by a tube seal (12). The space in front of the cormorant (cormorant, tube sea) (12) is the entrance chamber (14) '(i-
(12) and Tubesea)
The space between (13) and (15) provides an exit chamber (15)a:. The inlet (16) provides a means for directing fluid into the inlet chamber (14). From the inlet chamber (14), fluid passes through a number of sleeve conduits (18) (commonly referred to as a bundle). An inner conduit (18), open at both ends, is secured to the tubesheet (12) by welding, soldering, or other suitable means.

Each conduit also extends from the head section (10) to the heat exchange section (11). As shown in FIG. 2, each inner conduit (18
) is surrounded by an outer conduit (19).

A channel (20) is formed by the annular space between the inner surface of the outer conduit (19) and the outer surface of the inner conduit (18). The open end of each outer conduit is typically secured to the second tubesheet (13) by welding, soldering or other suitable means, thereby connecting the channel (20
) is in fluid communication with the outlet chamber (1,5) and the outlet (17). The inner conduit (18) and the outer conduit (19) are the fourth
They are mutually concentric as shown in more detail in the figure. In the practice of the invention, the channels (20) between these tubes (18, 19) allow the cryogenic fluid exiting the conduit (18) to be in contact with the large tube sheet (13) in the outlet chamber (15). It provides a passageway through which water can flow.

As shown in Figures 6 and 7, the inner conduit (18) is centrally located within the outer conduit (19) and the position and size of the rods (40) are such that these rods are connected to the channel (20) +
It is of such a degree that it does not significantly restrict the flow of fluid therethrough. The drawings, particularly FIGS. 2, 3, and 8, are simplified by assuming that the conduits (18, 1, 9) occupy only a part of the head section (10) in the heat exchange section (11). It shows. In the actual fabrication of the heat exchanger, the conduits (18,
19) occupies most of the cross-sectional area formed in the head part and the heat exchange part.

As shown in Figure 5, this part of the conduit (19) extending into the heat exchange part (11) is preferably a
) supported by some suitable member. The support member for the outer conduit also includes a number of spaced struts (39)' fixed between each of the concentric rings (38).
Including e. In particular, the outer conduits (19) are arranged between the rings (38) such that each outer conduit is wedged between adjacent support members (39).

Referring again to FIG. 2, the heat exchange portion (11) formed by the boundary wall (21) is the portion of the heat exchanger in which heat is transferred from the hot fluid to the cold fluid. The high temperature fluid enters the inlet (2
8) Enters the heat exchange part (11) through k and leaves the heat exchange part through exit (29)'e. Within the heat exchange part (11) there is a narrow space (27) formed between each of the outer conduits (19) and between the conduits (19) and the boundary wall (21). This space (27) provides a passage for the hot fluid to pass through the heat exchange portion (11)e.

Hermetic sea) (25) is connected to 7 lunges (22) and boundary wall (2
1) and between the flange (22) and another flange (
24) forming the terminal wall of the C end wall (26)]. These flanges are secured together by poles (23) and the sealing sheet (25) is secured to the boundary wall. The conduits (18, 19) are sealed with a sealing sheet (25)
Th passes through, but is not attached to this seat. Instead, the outside of each conduit (19) and the sealing sheet (2
5) It is preferable to leave a small gap (not shown) between the two.

This allows the conduit to move freely, i.e. expand or contract in response to temperature or other changes, without creating any unwanted stresses.

The wall (26) has a head portion (10) and a heat exchange portion (11).
) and provide the necessary connections between them. During implementation, walls (2
6) It must be thin enough to minimize heat transfer from the heat exchange part to the head part, but it must also be thick enough to provide a strong connection between the head part and the heat exchange part. It has to be something like that. Since the sealing sheet is not fixed by mechanical or other means to the boundary wall (21) or to the thin end walls, thermal stresses in the heat exchanger are reduced even further. -\The Rad section (10) is further insulated from the high temperatures of the heat exchange section by a cooling fluid chamber (34) which acts as a thermal sleeve. As shown in Figure 2, the chamber (34) is the tube sheet (13) and the sealed part!
-4 (25), and is surrounded by a connecting wall (26). An inlet (33) extending through the top of the flange (24) provides a means for directing cooling and purging fluid (hereinafter referred to as ``cooling fluid'') into the chamber (34). To prevent excessive mechanical and thermal stresses, the inlet (33) has a thin wall (2
6) placed in the flange (24) rather than in the flange (24);

The cooling fluid chamber (34) is in fluid communication with a member that uniformly distributes the cooling fluid over the entire cross-sectional area defined by the boundary wall (21). As shown in Figure 2, an insulating material (30) is placed within the area formed by the impingement plate (31), the wall member (32) and the sealing member (25).

Fluid communication between the insulating member (30) and the cooling fluid chamber is provided by gaps (not shown) between the outer conduit (19) and the sealing member (25) and between the outer conduit and the wall member (32). not given). The insulating material is a sealing member (25)
Its use is optional, although it serves to insulate the heat exchanger parts from high temperatures and provides a more even distribution of the cooling fluid over the entire effective cross-sectional area. When using thermal insulation materials, preferred materials include compressed mineral wool, aluminum oxide fibers, 1hryupool noalumina silica ceramic fibers, and the like. The impingement plate (31) and wall member (32) are made from thin sheets of refractory metal or other conventional refractory materials.

The heat exchanger of the present invention can be used in a wide variety of heat exchange operations. For example, the hot and cold fluids can be gases, liquids, or mixtures of gas and liquids. in general,
Hot fluids are typically hot gaseous substances, and cold fluids are cooling liquids and/or gaseous substances. In certain heat exchange operations, it may be desirable for the cold fluid and/or the hot fluid to undergo a phase change as these fluids move through the heat exchanger. For example, it is often preferable for a cold fluid to evaporate when cooling a hot fluid. Such phase changes can be easily accomplished during operation by selecting cold and/or hot fluids that exhibit the desired phase change under actual operating conditions.

The heat exchange operation of the present invention is particularly useful for cooling hot reaction products from pyrolysis or catalytic cracking reactions. The temperature of such reaction products is generally 700-1000°C
is within the range of

In such operations, the cryogenic fluid is preferably an aqueous liquid, usually water. Generally, water is about 100 to 400
It should have a temperature of °C. In heat exchange operations, the head section (10) is generally exposed to high pressures and low temperatures, while the heat exchange section (11) is exposed to high temperatures and low pressures of the hot fluid. Heat exchange occurs by transferring heat from a hot fluid to a cold fluid.

Referring to FIGS. 1 and 2, a typical heat exchange operation involves passing hot fluid from an inlet (28) into a heat exchange section (11). Inside the heat exchanger section, the hot fluid flows through the spaces between the conduits (19) in the direction indicated by the arrows (58).

At the opposite end of the heat exchanger, a cryogenic fluid such as water is supplied from a suitable source such as a steam drum (59) to an inlet (16).
) '(i-) into the head part (10). From the head part (10), the cryogenic fluid passes through an internal conduit (18) (e.g. a tube) open at both ends to the heat exchange part (1
1) IC flows. The cryogenic fluid flow path is indicated by 60. The portion of each inner conduit (18) within the heat exchange part (11) is surrounded by an outer conduit (19). As shown in FIG.
8) into the head part (10) through a channel (20) formed by the outer surface of the head part (10).

When the cold fluid is water, the heat transferred from the hot fluid is generally sufficient to evaporate at least a portion of the water to water vapor. This mixture of liquid water and steam generated during the heat exchange operation flows along the flow path indicated by (61) through channels (20)k to the head section (10).

From the head part (10), the mixture of water and steam is recycled to the steam drum (59) (channel 61).

As the hot fluid flows through the heat exchange section (11) along the flow path designated by (58)K, the hot fluid imparts heat to the cold fluid. After the hot fluid has cooled, it passes through the product outlet (29).

During operation of the heat exchanger, the insulating fill (30) and cooling fluid protect the sealing sheet from extreme temperature changes and corrosion or fouling. A wide range of fluids are suitable as this cooling fluid. Can steam be used? This is a typical example of M ejecting fluid. At the outlet (29), the temperature of the cooling fluid is below the temperature of the hot fluid, but the pressure of the cooling fluid is also higher than the pressure of the hot fluid. In Figure 2, the cooling fluid flow path is indicated by arrows (63). As mentioned above, the sealing member (2
5), a gap (not shown) exists between the wall member (32) and the outer conduit (19). These gaps are chambers (
34) to the insulating filler (30).

Since the pressure of the cooling fluid is higher than the pressure of the hot fluid,
The cooling fluid flows from the chamber (34) to the insulating glass (30) K.
Not only does it flow, but it also flows over the insulating optical fiber and into the heat exchange portion (11). From the heat exchange part (11), the cooling fluid is discharged together with the hot fluid through the product outlet (29)'i. Therefore, in operation of the heat exchanger of the present invention, the high temperature of the heat exchange part is gradually dissipated in the direction of the head part. This feature of the heat exchanger of the present invention provides significant advantages over known heat exchangers. Specifically, the heat exchanger does not have the material construction problems of known heat exchangers due to extreme temperature and pressure differences between hot and cold fluids.

In many operations, for example in the cooling of hot reaction products from a pyrolysis or catalytic cracking reactor, the temperature of the hot fluid after the entire hot fluid has been discharged from the product outlet, but before being recovered as the final product. Further reductions are often preferred. In the practice of the invention, the temperature of the hot fluid is further reduced by quenching it in a second exchanger (not shown) of the type described herein or another type of heat exchanger. The temperature at which the reaction product from the hydrocarbon cracking reactor leaves the product outlet (29) is generally between p300 and 700C.

In the practice of the invention, the reaction products are transferred to a second heat exchanger (
(not shown) to a temperature lower than 200-400°C.

The heat exchanger of the present invention can be cleaned by a simple and easy method. The process is carried out by simply replacing the hot fluid with fully superheated steam and cutting off the cold fluid supply. For example, in cleaning or decoking operations of heat exchangers used to cool reaction products from hydrocarbon cracking reactors.
The inlet (
28). At the same time, the flow of purge fluid through the inlet (33)2 is maintained to protect the head section (10) from extreme temperatures. With sufficient isolation, the temperature of the head section is generally maintained below about 500°C, preferably between about 300 and 400°C.The superheated steam is heated to between 300 and 300°C by injection of water after leaving the outlet (29).
Cooled to 700°C. This water vapor can be further cooled using conventional techniques. Because the heat exchanger of the present invention is continuously maintained at its normal operating temperature, the thermal stresses normally associated with cleaning the heat exchanger are significantly reduced.

Another embodiment of the heat exchanger of the present invention is shown in FIG. The head section, heat exchange section, and heat exchange operations are substantially the same as described for the heat exchanger shown in FIG.

The same reference numerals are used for similar elements in each embodiment.

However, in the embodiment of FIG. 3, the outer conduit (19) is physically secured to both the second tube sheet (13) and the closure member (25) by welding, soldering or other suitable means. There is. This structure provides the necessary attachment l between the head part and the heat exchanger part and provides a thin wall (2
6) is no longer necessary.

The sealing member (25) is placed between the flange (22) and the outer clamping member (35) and is secured in position by a suitable securing member, such as the flange (22) and the outer clamping member (35). The sealing member (25) in this embodiment (FIG. 3) K is movable because it is not firmly attached to a fixing member.

This allows it to expand and contract when exposed to temperature changes (similar to the sealing member (25) in the embodiment of FIG. 2) without causing excessive stress.

Between the sealing member (25) and the second tube seat (13) there is a space preferably open to the atmosphere. A cooling fluid inlet conduit (36) is located in this space which directs the cooling fluid to the heat exchanger section (11). As shown in FIG. 3, the inlet conduit (36) is T-shaped and has one side arm with an open end and one side arm with a closed end. The side arm at the open end is sealed (25
) k and is at least partially surrounded by the sleeve (37). The open end side arbor also has a number of small openings internally opening into the sleeve (37). The sleeve (37) also transfers the cooling fluid to an insulating material (
30) Has a large number of small openings inside to allow water to flow inside. The side arms of the conduit (36) and the sleeve (37) are preferably low 1? + Located in the center of a bundle of conduits carrying fluid. Furthermore, the side arm structure also extends laterally through the heat exchanger to uniformly distribute the cooling fluid through the insulating material (30).

As shown in Figure 3, a cooling fluid inlet (3
The side arms of (6) extend into the opening of the second tube (13). This arrangement is optional, but is preferred as it provides rigidity to the structure of the heat exchanger. There is no opening in the wall of this side arm, but the arm itself has an entrance (36
) is in fluid communication with the cooling fluid entering the cooling fluid. Connect the heat exchanger to the sealing member (25) and/or the second tube
, 13) It is possible to achieve a more uniform distribution of the cooling fluid through the insulating material (30) ``! The construction is undesirable because it reduces the number of conduits used to transport the cryogenic fluid, thereby reducing the capacity of the heat exchanger.

Another embodiment of the heat exchanger of the present invention is shown in FIG.

The head section, heat exchange section and method of operation are the same as the embodiment of the heat exchanger shown in FIGS. 2 and 3. Similar parts of each embodiment are designated using the same reference numerals. However, in the embodiment of FIG. 8, a cooling fluid distribution element (41) is provided between the second tube seat (13) and the sealing element (25). This distribution member (4
A cooling fluid chamber (46) is arranged between the first tube (1) and the second tube (13). The cooling fluid enters the heat exchanger through an inlet (43)'(r) communicating with the chamber (46). A sealing member (25) is disposed between the flanges (35, 22) and is is held in position.

A number of cooling fluid sleeves (44) are connected at one end to the distribution member (41) and at the opposite end to the sealing member (25).
) is fixed. These sleeves, which are fixed to the parts (41, 25) by welding, soldering, hammering or other suitable means, connect the head part and the heat exchange part (11).
Provides the only mechanical connection between the

The sleeve (44) has a distribution member (41) and a sealing member (25).
) of each inner conduit (18) and outer conduit (19) extending between the inner and outer conduits (18) and (19). The sleeve (44) has a larger diameter than the outer conduit (
A channel (45) is present between the outer surface of the sleeve (44) and the inner surface of the sleeve (44). The dimensions of the enclosure, sleeve (44), in relation to the outer conduit (19) are best shown in FIG. 9. The channel (45) is the entrance (4
3) and an insulating material (30). This arrangement allows the cooling fluid entering the inlet (43) to flow into the channel (45) as shown at (63) and the insulating material (
30) to enable uniform dispersion.

In the embodiment shown in FIG. 8, heat transfer from the heat exchange section to the head section is significantly reduced. This is because in this specific example, there is no wall member that completely separates these two parts (the heat exchange part and the head part). Also, the front side of the heat exchange portion is open to the atmosphere, and the cooling effect of the ambient atmosphere helps reduce the amount of heat transfer that occurs. Thermal stresses in this embodiment of the heat exchanger are also minimized by the fact that the outer conduit (19) is fixed to the second tube (13).

Some details regarding materials of construction, operating conditions and other features of the heat exchanger of the present invention are set forth below. The conduits carrying the cryogenic fluid are made of materials capable of withstanding the temperatures and pressures normally present in heat exchanger operation. For example, in operation f1, which involves cooling the reaction products of a hydrocarbon cracking reactor, the cryogenic fluid has a temperature of about 100-350°C and a pressure of up to 140 atmospheres. Typical materials that can withstand these conditions are nickel and nickel-based alloys such as iron, chromium, cobalt, molybdenum, tungsten, niobium, and tantalum. These metals or metal alloys may also contain non-hazardous additives such as silicon and carbon, which are preferred for making various components of heat exchangers and are commonly used in heat exchange operations and cleaning operations. *Compatible with the temperatures and pressures encountered. When the heat exchanger is used to cool the hot reaction products of a hydrocarbon cracking reactor, the temperature and pressure during the heat exchange operation is approximately 70°C.
0-10QO<0>C and about 2-10 atmospheres. During the superheated steam decoking or cleaning cycle, the temperature is about 900-1100 C and the pressure is about 2-10 atmospheres. Preferred materials that withstand these conditions are nickel and nickel-based alloys.

Since most of the heat in the heat exchanger section is gradually dissipated without being transferred to the head section, the structural materials of the head section need not be designed to withstand the high temperatures of the heat exchanger section. For example, the head section experiences a maximum temperature change of 500 degrees Celsius or less. That is, the maximum temperature experienced by the second tube sheet is about 300° C. lower than the temperature of the hot fluid entering the heat exchange section. Generally, the preferred material for making the head portion is a chromium and molybdenum steel alloy.

The size and shape of the heat exchanger and each of its component parts, i.e. conduits, tubesheets, sealing members,
The housing, etc. is determined primarily by the particular operation in which the heat exchanger is used and the normal conditions of such operation, such as the pressure differential that exists between one side of a tubesheet and the other side of the same tubesheet. As previously mentioned, temperature and pressure conditions change very gradually during operation of the heat exchanger of the present invention. For this reason, the tubesheets and other elements of the heat exchanger do not need to be designed to withstand large temperature and pressure differences.

[Brief explanation of the drawing]

Figure 1 is a schematic illustration of the heat exchanger of the present invention showing the flow path of fluid through the heat exchanger during heat exchange operations. FIG. 2 is a front view, mostly in section, of a particular embodiment of the heat exchanger shown in FIG. FIG. 3 is a front view, mostly in section, of another embodiment of the heat exchanger shown in FIG. FIG. 4 is a cutaway cross-sectional view taken along line IV--IV of FIGS. 2 and 3 showing the tubesheet and tube bundle of the heat exchanger. FIG. 5 is a cutaway cross-sectional view taken along the line V-V in FIGS. 2 and 3, showing a portion of the tube bundle in the heat exchange section of the heat exchanger and members supporting the tube bundle. It shows the meeting. FIG. 6 is a detailed cutaway view of the sealed end of the outer conduit in the tube bundle, showing the inner conduit disposed within the outer conduit and the members within the outer conduit supporting the inner conduit; It is something. FIG. 7 is a cross-sectional view taken along the line ■--■ in FIG. FIG. 8 is a front view, mostly in section, of yet another embodiment of the heat exchanger shown in FIG. FIG. 9 is a cross-sectional view taken along line IX--IX in FIG. 8, showing the structure of the tube bundle at this location in the heat exchanger. 10... Head part, 11... Heat exchange part, 12... First tube seat, 13.
...Second tube seat, 14...Inlet chamber, 15...Outlet chamber, 16...Inlet for low temperature fluid, 17...Low temperature Fluid outlet, 18...
...Inner conduit, 19...Outer conduit, 20.
...Annular channel, 21...Boundary wall,
22.24...Flange, 23...Bolt, 25...Sealing member, 2 fi...
- End wall, 27... High temperature fluid passage, 28...
...Hot fluid inlet, 29...Product outlet,
30... Insulating optical fiber, 31... Collision plate, 32... Wall member, 33... Cooling fluid chamber [=1.34. ...cooling fluid chamber, 35
...Outer clamp member, 36...Cooling fluid inlet conduit, 37...Sleeve, 3B...
... Concentric ring, 39 ... Support column, 40 ...
...Holding rod, 41...Distribution member, 43...
... Cooling fluid inlet, 44 ... Cooling fluid sleeve, 45 ... Annular channel, 46 ...
... Cooling fluid chamber, 58 ... Flow direction of high temperature fluid, 59 ... Steam drum, 60.61.
. . . Flow direction of low temperature fluid, 63 . . . Flow direction of cooling fluid. Procedural amendment (method) April 12, 1980 Director of the Japan Patent Office Kazuo Wakasugi 1. Indication of the case 1988 Patent P6 No. 44583 2. Name of the invention Heat exchanger and its operating method 3. Make amendments Relationship with the patent case + name of person The Dow Chemical Company Akasaka Taisei Building (
582-7161) Drawing attached to the guest of honor

Claims (1)

[Claims] 1. A heat exchanger for cooling a first fluid at a predetermined temperature and pressure by a second fluid at a lower temperature and higher pressure, the low temperature a head part comprising an inlet and an outlet for the fluid; and a heat exchange part comprising a bundle of inner conduits, each of which is open at both ends and extending from said head part to the heat exchange part. wide and in fluid communication with the cryogenic fluid inlet to permit passage of the cryogenic fluid through the respective inner conduits; the heat exchange portions further included in the bundle of outer conduits;
Each outer conduit is in fluid communication with said cryogenic fluid outlet and surrounds the portion of the respective inner conduit within the heat exchange section between the inner surface of the outer conduit and the outer surface of the inner conduit. a channel is formed in the inner conduit, and the channel provides a means for flowing the cold fluid exiting the inner conduit to the outlet of the head section; It also includes an inlet and an outlet, and has a space therein for passing the hot fluid from the inlet to the outlet so that the hot fluid comes into contact with the conduit containing the cold fluid:
and a temperature regulating zone disposed between the head portion and the heat exchange portion, the zone being adapted to receive a fluid having a temperature lower than that of the hot fluid and a pressure higher than the hot fluid; A heat exchanger in which the receiving fluid provides a means for gradually decreasing the temperature from the heat exchange section to the head section. 2. The inner conduit is fixed at one end to the first tubesheet, the outer conduit is fixed at its open end to the second tubesheet, and an insulating filler is disposed between the head section and the heat exchange section. and adjacent a sealing member between the second tube seat and the hot fluid outlet, the inner conduit and the outer conduit passing through the sealing member, and the sealing member being adjacent to the sealing member between the second tube seat and the hot fluid outlet, and the inner conduit and the outer conduit passing through the sealing member, and the sealing member being adjacent to the sealing member between the second tube seat and the hot fluid outlet. 2. A heat exchanger according to claim 1, having passages therein for providing fluid communication between the heat exchanger and the heat exchanger. 3. The thermal sleeve is provided by a cooling fluid chamber, which cooling fluid chamber is composed of a thin surrounding wall firmly connected to the head part and the heat exchange part, and a side wall formed by the second tube sheet and the sealing sheet. 3. The heat exchanger of claim 2, wherein the heat exchanger has a fluid entry location within the chamber, and wherein the chamber is in fluid communication with the insulating material by a passageway formed between the sealing member and the outer conduit. . 4. The outer conduit is fixed to both the second tube sheet and the sealing sheet, and a space is formed between the second tube sheet and the sealing sheet, and the space is open to the atmosphere, and the cooling An inlet vibrator for the service fluid extends into said space, and the pipe has a side arm with an open end surrounded by a sleeve, and the sleeve and side arm pass through a sealing sheet to an insulating filling. 3. A heat exchanger according to claim 2, wherein the sleeve extends through the material and has at least one hole therein to allow cooling fluid to flow through the insulating material. 5. The heat exchanger of claim 4, wherein the side arms of the inlet vibe are substantially centered on the longitudinal axis of the heat exchanger. 6. A heat exchanger as claimed in claim 4 or claim 5, wherein the inlet vibe has a side arm with a closed end extending into a hole in the second tube sheet. 7. A cooling fluid distribution member is disposed between the second tube seat and the sealing member, a cooling fluid chamber is disposed between the second tube seat and the cooling fluid distribution member, and the cooling fluid inlet is disposed between the second tube seat and the sealing member. The heat exchanger includes a bundle of spools, each sleeve open at both ends, for communicating fluidly with the cooling fluid and a cooling fluid distribution member. A channel is formed between the inner surface of the sleeve and the outer surface of the outer conduit by enclosing the entire portion of the outer conduit that extends intermittently with the sealing sheet, and the channel is formed between the cooling fluid chamber and the sizing filling. 3. A heat exchanger according to claim 2, further comprising a space between the cooling fluid distribution member and the sealing member, the space surrounding the sleeve and being open to the atmosphere. 8. The insulating filling is arranged in an enclosure formed by the impingement plate in contact with the hot fluid in the heat exchange part;
An outer conduit passes through the impingement plate to form a passageway between the conduit and the impingement plate in which cooling fluid in the insulating material can flow through the passageway into the hot fluid. Claim 2. The heat exchanger according to any one of Items 3, 4, or 7. 9. The following steps: passing the hydrocarbon reaction product as a hot fluid through a heat exchanger through the hot fluid inlet: through the heat exchanger through the fluid inlet: indirect contact of the hydrocarbon reaction product with water to partially cool the reaction product and evaporate or heat the water; The hydrocarbon reaction product is further cooled by direct contact with the passing water vapor: the cooled hydrocarbon reaction product is discharged from the heat exchanger through the hot fluid outlet with all the water vapor: and the evaporated or heated water is A method of cooling reaction products from a hydrocarbon cracking reactor, comprising: discharging through an outlet for cryogenic fluid. 10. Cut off the flow of hydrocarbon reaction products through the heat exchanger from the flow of water; pass the superheated steam at a temperature of about 900 to 1100°C into the heat exchanger through the hot fluid inlet. 10. The method of claim 9, further comprising: removing the internal coke deposits: and discharging the coke deposits along with the hot fluid through a hot fluid outlet.