DE1945482A1 - Heat exchanger and process for cooling hot gases - Google Patents

Description

Dr. ing. E. BERKENFELD ■ Dipl.-Ing. H. BERKENFELD, patent attorneys, Cologne Attachment file number

on the submission of June 26, 1969 Sch // Name d. Note stone & Webster Engineering

Corporation

Cooling device and method.

The invention relates generally to an apparatus and a Method for cooling a medium and in particular a device and a method for rapidly cooling a medium. The device and the method according to the invention are particularly suitable for rapidly cooling a drain coming from exits a furnace for cracking hydrocarbons.

The invention relates to a device and a method, which are used for the rapid cooling of hot media. The device contains a device by means of which a hot medium is brought into contact with cooling surfaces in order to bring about a rapid decrease in the temperature of the hot medium. The cooler is suitable for cooling media under increased pressures. The device according to the invention can be used for rapid cooling hot gases can be used without a significant change in pressure.

The cooling device finds particular and advantageous application in Relation to a process for producing olefins by cracking hydrocarbons at high temperature and short Dwell time using a furnace with high radiant heat is, which has relatively short lines of small diameter. The cooling device is used to make a rapidly reducing the gas temperature of the furnace effluent without causing a substantial drop in pressure.

The gas temperatures of the effluent from the cracking furnace are very high high and at these high temperatures the cracking reactions take place

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very quickly in front of you. To the reactions in the effluent gas essentially to interrupt and reduce the generation of undesirable by-products to a minimum, it is necessary to remove the waste gas, after it leaves the reactor, to cool rapidly to a temperature at which the reactions essentially stop. Several means are available to this end, most of which have one or more disadvantages. the Conventional cooling equipment such as a tubular heat exchanger has resulted in a substantial pressure drop in the effluent gas. These The type of heat exchanger uses multiple tubes and comes with one Inlet head provided. The residence time of the hot gases in this Head alone is important at the temperatures used and results in degradation of the product and the formation of coke precursors and coke, both of which can collect in the heat exchanger.

When cooling the high temperature effluent gases from a hydrocarbon cracking process used for Generating olefins is used, the temperature of the cooling device must be low enough to keep the gases in the desired Cool to a degree, and high enough to prevent condensation of the high-boiling by-products of the hydrocarbon on the cooling surfaces to prevent.

The cooling method and apparatus according to the invention are particularly useful in cooling the effluent gases from a process for the thermal cracking of hydrocarbons. With thermal Cracking of hydrocarbons can in the process described below, the supplied hydrocarbon to a heated to a high temperature, kept at the high temperature for a short period of time and optionally in the desired Products are converted. According to the invention, the reaction products the hot gases are rapidly quenched or cooled in such a way that the conversion occurs after the desired residence time is essentially interrupted "

The cooling device and the cooling method according to the invention are particularly suitable for use to cool down the hot Waste gases emitted from a pyrolysis oven * Use the

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However, this concept can easily be applied to other methods of cooling hot product flows, to which heat recovery and / or to the heating of media are used. The cooler and the process can be used to rapidly cool hot gaseous products from other cracking processes. The cooler causes indirect cooling on surfaces. The device is simple and easy to operate. The device can be of any size and is usually designed for a particular purpose. The device can be arranged horizontally or vertically. The cooling device cools hot media are released quickly, whereby the pressure of the media is not significantly changed. That means that the pressure of the cooled down Medium at the outlet of the cooling device is substantially equal to the inlet pressure. The medium to be cooled can be upwards or downwards stream. The device can be operated in such a way that the circulation speed of the coolant regulates itself and adjusts itself to the heat load within certain limits. The circulation speed of the coolant can also monitored by auxiliary pumps.

Similar devices and methods are described in U.S. Patents 3,407,789 and 3,057,722. Furthermore, to U.S. Patent Application No. 729,876 filed May 10 1968 referred to, which a separation from the American patent application No. 557 005 from I5. June 1966 is. Finally will Reference is made to co-filed American Patent Application No. 802,789 dated February 27, 1969.

An apparatus and a method are described below which allow heat exchange between a hot drain and a coolant effect. The heat exchange device is essentially tubular and with a diverging Inlet section provided which has an angle of divergence of less than 10 °.

The heat exchanger according to the invention is with a passage for ■ the flow of the hot medium through the same and provided with at least one coolant drain. The passage for that hot medium and the passage or passages for the cooling

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means are arranged so that they have common walls, through which an indirect heat exchange takes place. The inlet of the passage for the hot medium is in the form of a diverging one Formed nozzle which has a divergence angle of 4-10 °.

A modified embodiment of the heat exchanger consists essentially of three concentric tubes, the walls of which have two form annular chambers and a central chamber. The cooling medium can be fed to the upper end of the device and into the middle chamber flow. The middle chamber stands at the end opposite its inlet with the first annular chamber in connection. The cooling medium can flow downward in the central chamber and upward in the first annular chamber and through an opening at or near the top of the first annular chamber. The outer wall of the second concentric The tube forms a cooling surface. The hot gaseous medium to be cooled can pass through an opening at the bottom of the cooling device enter in the third concentric pipe and through the second flow upward in the ring-shaped chamber and be cooled by direct contact with the cooling surface. The cooled medium can come out exit the cooling device through an outlet located near the top of the second annular chamber.

For a better understanding of the invention, the same will be explained below described with reference to the drawings in which shows:

Pig. 1 schematically shows a flow diagram of a thermal Cracking system provided with the cooling device according to the invention,

Fig. 2 in longitudinal section an embodiment of the cooling device,

3 shows the concentric tubes and the cooling tubes of the cooling device in cross section along the line 3-3 of FIG. 2,

4 shows in longitudinal section another embodiment of the cooling device according to the invention,

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Pig. 5 the concentric tubes and the cooling fins of the

Cooling device in cross section along the line 5-5 of FIG. 4,

6 shows yet another embodiment in longitudinal section the cooling device according to the invention,

7 shows the cooling device in cross section along the line 7-7 in FIG. 6,

Fig. 8 in longitudinal section a further embodiment of the cooling device according to the invention,

FIG. 9 shows the cooling device in cross section along line 9-9 in FIG. 8.

The heat exchanger according to the invention is described as part of a system for thermal cracking of hydrocarbons for the production of olefins. The heat exchanger according to the invention is an indirect heat exchanger that has a passage for the flow of a hot drain through the same and at least has a cooling chamber with a common wall therebetween.

The cooling device can use any desired cooling medium. The cooling medium can be a liquid which partially or completely evaporates when heated. The preferred cooling media are liquids. Appropriate liquids are Dowtherm, water, etc.

The preferred cooling liquid is water. In the illustrated embodiment, the cooling device is used to remove steam from generate high temperature and high pressure. The heat energy recovered during cooling can be used for power generation or for Can be used for heating purposes.

Referring to FIG. 1, a typical reactor furnace and a cooling device will be described. A Petroleumnaphthafraktion in the range of 32 - 190 ⁰ C is boiling, through the conduit 1

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introduced into the convection preheating section 7, in which the same is heated from the ambient temperature to a temperature of about 538 - 595 ° C. Steam in a weight ratio of steam to hydrocarbon of about 0.4: 0.8 is introduced into the preheating section 7 through lines 8 and / or 9 at a point at which approximately 80% of the supplied naphtha has evaporated. The mixture of hydrocarbon and steam, preheated to about 558-593 ° C., is then fed to the distributor 2 and the inlets of the coils 3-6 . The feed mixture is heated in the coils from 538 - 593 ° C to an outlet temperature of about 899 ° C. Under the specified conditions, the partial pressure of the hydrocarbon at the pipe coil outlet is about 0.84-0.98 ata. The residence time of the medium in the radiant section of the furnace is about 0.20-0.25 s, and the mass velocity of the hydrocarbon and steam in the coils is about 87.876-126.932 kg / s / m of the cross-sectional area of the coil. The pressure of the effluent gases at the coil inlet is about 3.15 ata, and the pressure at the pipe coil outlet is about 1.75 ata. The hot effluent gases are fed from the outlet manifold 11 through the conduit 12 to the cooling device 14 at a gas velocity of about 240 m / s. The hot gases are introduced into the cooler through inlet I3 at a temperature of about 899 ° C. The cooled gases are discharged from the cooling device through outlet I5 which is connected to line 16. The gases are rapidly cooled to a temperature of about 649-760 ° C. in about 10-20 ms and can be fed to a conventional cooling device for further cooling and a conventional olefin separation plant for the purpose of separating and recovering ethylene. The gas pressure in line 16 is about 1.75 ata.

The heat exchanger 14 according to the invention may cool the furnace effluent rapidly to 38-315 ⁰ C, ie, from about 815 to 899 ⁰ C to about 538 ⁰ 76o C. After the discharge section of the furnace the radiation has left the cooling is very rapid in carried out for about 1 - 30 ms, preferably in about 5 - 20 ms. Rapid cooling is critical in the high temperature and short residence time process for cracking hydrocarbons to produce olefins. If the cool down takes much longer

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than 50 msec, it was found that considerable coke deposits in the internal passages of the cooling device and downstream thereof.

When high temperature and short dwell times are used to crack hydrocarbons to produce olefins, it is necessary to cool the furnace effluent rapidly enough below the reaction temperature to essentially bring the reaction to a standstill. If this does not happen, the reaction will continue after the effluent leaves the reaction zone and can result in degradation of the product, a decrease in the yield of ethylene and increased production of polynuclear aromatics and / or other compounds of low volatility. Such products tend to cause coke to be deposited on the walls of downstream facilities. At 871 ⁰ C, the reaction rates are so high that can be carried out at a residence time in a cooling zone of only 50 ms, a considerable reaction. It is therefore important to cool the drain very soon after leaving the furnace to a temperature at which essentially no harmful reaction occurs, i.e. to a temperature below 593 - 760 C.

Fig. 1 of the drawing illustrates the thermosiphon cooling according to the invention. Cooling water from the steam container I7 is introduced through conduit 18 at a temperature of about 315 ⁰ C and under a pressure of about 112 ata. The cooling water flows through the line 18 into an annulus 19 and up the pipes 20, in which the water is partially converted into steam. The mixture of steam and water flows into the annular space 21 and through the line 22 back into the steam container I7. The water, which is denser than the mixture of steam and water, creates a thermosiphon flow of the cooling water through the cooling device. The cooling device is self-regulating within certain limits. The higher the temperature and the flow speed of the gases in the cooling device, the greater the circulation speed of the cooling water will be.

Can ata saturated steam at a temperature of about 315 ⁰ C and a pressure of about 112 from the steam container by I7

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the line 23 withdrawn and the thermal energy recovered. Boiler feed water is fed to the steam tank 17 through line 2 #.

The heat exchanger according to the invention can be used in other known Procedure used., But is special for a. system suitable for cracking hydrocarbons. Of course, of course The cooling device can have many applications for cooling product flows, for heat exchange and for others; Find purposes which are easily recognizable to the person skilled in the art.

The heat exchange device according to the invention: includes a Means by which the hot furnace effluent is in a heat exchange passage is cooled. If the heat exchange passage is annular, one or both of the surfaces may be the forming the annular passage, a heat transfer surface be. This cooling device is particularly suitable for rapid cooling hot gases;, with little reduction or substantial no change in the pressure of the medium to be cooled, while high-pressure steam is generated in an economical manner.

An embodiment of the invention is shown in FIGS. 2 and J5. The heat exchanger 14 is an indirect heat exchange device, which cools the furnace drain or similar hot medium and generates high pressure steam. The inlet end of the heat exchanger is designed so that the speed of the furnace effluent flow is gradually slowed down so that the dynamic pressure or kinetic energy is converted into static pressure. The pressure recovery achieved can partially or fully compensate for the pressure drop due to friction as it passes through the device compensate, depending on the particular dimensions of the device and the conditions under which it is operated will. The rapid cooling of the gas is effected by passing it through a tubular passage which cools is. .

The heat exchanger 14 consists of a centrally arranged tube 25 which extends over the entire length of the device and ends in iron outlet 26. The inner wall 27 of the tube 25 is limited

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the passage or chamber 28 through which the drain to be cooled is directed. At the upper end of the tube 25 is a connecting device 29 provided in order to be able to connect the heat exchanger 14 to the transmission.

The wall of the tube 25 is provided with a plurality of equally spaced tubes 20 which are connected to the outer wall 3I of the tube 25 and are in close contact therewith. These tubes extend almost the entire length of the wall and are bent outward at their upper and lower ends by curved tails 32 and 33, which are in communication at the upper end with the annular space 21 and at the lower end with the annular space 19. The annular space 19 has a connecting line J> 6 through which the cooling medium passes through the inlet 37 into the annular space 19 and flows upwards through the tubes 20. The tubes 20 are connected to the upper annular space 21 and the cooling medium flows out of the annular space 21 through the outlet 38 and the line 39.

At a point close to the end at which the drain enters the cooling device, the tube 25 is tapered inward, to form the inlet port 40. It is so dimensioned that the cross-sectional area of the passage from the inlet opening 40 to the cooling chamber 28 gradually increases, by an inlet diffuser section 41 to form.

The cooling device can be designed and dimensioned to adapt to any desired cooling purpose. The cooling device which can be used according to the invention can have a total length of 9-45 m from the gas outlet 26 to the inlet 40 of the hot gases. The inside diameter of the tube 25 can be 6.25-12.5 cm. The inner diameter of the annular spaces 19 and 21 can be approximately 7.5-15 cm. The cross-sectional area of the gas inlet 40 can be approximately 19.356-90.328 cm 'and gradually increases to 25.808-129.040 cm ² in the straight part of the tube 25. The total flow of coolant through tubes 20 may be approximately ten times the flow of hot waste gases by weight.

The hot gases occur at a speed of 210 - 240 m / s through inlet 40 into the cooling device and enter the

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Chamber 28, in which they are slowed down to about 120-150 m / s, whereupon they exit the device through the outlet 26 at the end of the chamber. The cooling water enters the lower annulus 19 through the inlet J ¹ J and flows up the tubes 20 so that indirect contact cooling for the hot furnace effluent gases on the inner wall 27 of the tube 25 results. The inner wall 27 of the tube 25 forms the cooling surface for the hot gases. -

The mixture of steam and water flows up the tubes 20 into the annular space 21 and exits through the outlet 38.

The inlet diffuser portion 41 causes the gradual increase the cross-sectional area for the gases entering through inlet 40 so that the pressure of the hot gases gradually increases as the gas velocity is reduced. The diffuser section ensures even gas distribution on the cooling surface 27, without a strong vortex being generated in the gas flow. According to the invention, by increasing the gas pressure, that by the gradual increase in the cross-sectional area in the inlet is effected, a substantial part of the gas pressure loss caused by friction is compensated. The outlet pressure of the cooled The gas is approximately equal to the inlet pressure of the hot gas. The passage 28 is sized so that the same the gradual increase the cross-sectional area through which the hot gases flow. The gradual increase is due to the tapered shape of the Wall of the diffuser section 41 causes.

The gradual increase in the cross-sectional area causes a gradual one Decrease in gas velocity resulting in an increase in gas pressure to preserve total energy.

The angle of divergence of the inlet pipe of the diffuser section 41 is in the range of 4 - 10 °, such as 5 °.

Flg. 3 shows the cooling device in cross section along the line 5-5 of Fig. 2. Fig. 3 shows the tubes 20 in section and the type and way as the same duroh welds 42 with the outer Wall of the tube 25 are connected. Heats transfer material 4}

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can be used to fill in the space between the. Pipes 20 used to improve the heat transfer between the hot gases and the coolant

In Figures 4 and 5 is another embodiment of the cooling device shown. In this embodiment, the hot gases are cooled by direct contact with the external one Wall of the concentric tube 25. In order to improve the heat transfer between the tube 25 and the cooling medium, the tube 25 may be provided with a plurality of cooling fins which protrude into the coolant passage 45.

The diffuser section directly adjoining the cooling chamber inlet 40 41 again consists of an inlet pipe which has an angle of divergence of 4-10.

The coolant chamber 45 completely surrounds the inner one Cooling chamber 28 so that tube 25 is directly exposed to the coolant passing through chamber 45. The coolant enters through inlet 46 which is near inlet 40 is for the hot drain, passes through the chamber 45 and exits through the outlet 47, so that the chamber 28 from Ehlaß 40 is cooled to the outlet opening 26.

In Figures 6 and 7 is yet another embodiment of the Cooling device shown. According to Fig. 6, the cooling device consists of three concentric cylinders or tubes that are perpendicular arranged -are. The outer cylinder is provided with a plurality of equally spaced tubes. The hot waste gases are inserted into the cooling device and rapidly cooled by indirect heat exchange through contact with two cooling surfaces.

The center concentric tube 152 has a at the top Inlet 175 and extends down to the middle Form passage 131. The second concentric tube 134 is on upper end curved inward and ends just before inlet 173 on the wall of the central tube 132. The outer wall of the tube 132 and the inner wall of the tube 134 form the annular one

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Karrimer 133 · Spacers 148 keep the tube 132 equidistant from the inner wall of the tube 134. The tube 134 forms at the lower end a rounded chamber and ends in a rounded end part 137 · The third concentric tube I36 extends extends over the entire length of the device and ends shortly before the upper end of the tube 134. Above the point at which the Pipe 136 ends, line 174 is through outlet port 175 with the annular chamber 133 in communication. The inner wall, of the pipe I36 and the outer wall of the pipe 1J4 form the two-ä te annular chamber 135 · Near the top of the annular Chamber 135 a deflection ring 146 is arranged, which prevents resting product gases in the upper end of the annular Accumulate chamber. Also near the top of the annular chamber 135 is a connector 144 provided, which through the outlet port 145 with the annular Chamber 135 is in communication. The deflection ring 146 and spacers 147 hold the concentric tube 134 in the center of the annular chamber 135

An important feature of the cooler is the I38 nose cone. The same is arranged in the axial direction of the tube 134. The base of the nose cone I38 is attached to the rounded end portion 137 and the vertex extends in the direction of the entrance, orifice 143. At one of the end of the straight part of the concentric Rohres 134 nearer point is the concentric one Tube 136 tapers inward in the direction of the nasal cone I38, to form inlet port 143. The cross-sectional area of the inlet 143 is dimensioned so that the cross-sectional area of the annular passage 14O from inlet 143 to annular Chamber I35 gradually increases through the walls of the tubes 134 and 136 is formed.

The outer wall of the concentric tube I36 is provided with a plurality of equally spaced tubes 161 which delimit passages I67 and which are connected to and in close contact with the outer wall I36. These tubes ^he itrecken s I almost the entire length of the outer wall 136 from the lowermost part of the same * The tubes 161 are up to the curved line 144 at the upper and lower Endentiurch

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Parts 16O or 162 bent outwards and stand at the upper end with the annulus 150 and at the lower end with the annulus 149 in Link. The annular space 149 is connected to a connecting line through which the cooling medium enters the annulus 149 through the inlet I63 and flows upward in the tubes I6I. the Pipes I6I are connected to the upper annulus 150 and the Cooling medium exits from the same through outlet I66 and the conduit 165 off.

The cooling device can be designed and dimensioned to adapt to any desired cooling purpose. The cooling device which can be used according to the invention can have a total length of 6 to 7.2 m from the coolant inlet 173 to the inlet 143 of the hot waste gases. The inner diameter of the third concentric tube I36 can be 20-25 cm. The inner diameter of the tubes 161 can be approximately 2.5-5 cm. The inner diameter of the hanging spaces 149 and 150 can be approximately 7.5-10 cm. The cross-sectional area of the central chamber formed by tube I32 can be 45.164 cm. The length of the middle chamber can be 5.4 - 6 m. The cross-sectional area of the first annular chamber 133 can be about 77.424 cm and it can have a length of about 5-6 m. The cross-sectional area of the second annular chamber 135 can be approximately 129.040 cm and it can have a length (excluding the inlet section) of 4.8-5 * 4 m. The cross-sectional area of the gas inlet 143 may be about 77.424-83.876 cm and may gradually increase to about 122.588-129.040 cm by the straight portion of the tube 134. The tapered nose cone 138 can have an angle of approximately 28-30 at its apex. The total cross-sectional area of the tubes 16I can be about 64.520-70.972 cm ² . The total flow of coolant through the tubes 161 and the first annular chamber 133 may be about ten times the flow of the hot waste gases by weight.

The hot gases occur at a speed of 210 - 240 m / s through inlet 143 into the cooler and pass into the second annular chamber 135 * in which it is about 120 150 m / s, whereupon they exit at the end of the chamber through outlet 145 of the device. That cools 27/10 -13-

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water is introduced through inlet I73 and flows into the middle chamber I3I of the concentric tube 132 downwards. A Mixture of water and steam flows up the first annular chamber I33 and occurs near the top of the same through the outlet port 175. The cooling water also enters the lower annulus 149 through inlet 16j3 and sfcreams upward in tubes I6I to provide indirect cooling for the hot furnace flux gases on the inner wall of the tube I36 cause. The inner wall of the tube I36 and - the outer wall of the Tube 134 form the two cooling surfaces for the hot gases.

The mixture of steam and water flows up the pipes 16I into annulus 150 and exits through outlet 166.

The inlet diffuser or 140 passing through the wall 139 and the nose cone 138 is formed causes a gradual increase in cross-sectional area for the hot entering through inlet 14-3 Gases, so that the pressure thereof increases as the gas velocity is decreased. The diffuser 140 ensures an even gas distribution on the cooling surfaces I36 and 134, without creating a strong vortex formation in the gas flow which would reduce the extent of the pressure increase. According to of the invention is achieved by the increase in gas pressure caused by the gradual increase in cross-sectional area in the inlet becomes, an essential part of the gas pressure loss caused by friction compensated. The outlet pressure of the cooled gas is approximately equal to the inlet pressure of the hot gas. The passage 140 is sized so that it causes the gradual increase in the cross-sectional area through which the hot gases flow. The gradual Increase is caused by the tapered shape of the nose cone I38 and the converging wall 139 of the tube I36.

The gradual increase in the cross-sectional area causes a gradual Decrease in gas velocity resulting in an increase in gas pressure to preserve total energy.

The angle of the nose cone I38 and the inlet tube 139 are like this chosen that the increase in cross-sectional area per unit length of the annular space between the cone I38 and the tube

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is equal to the increase in cross-sectional area per unit length of a conical tube that has an angle of divergence of 4-10 °, such as 5 ° · The angle of the cone I38 and the extent to which the converging wall 139 corresponds to the angle of the Cone 138 gives the gradual increase required the cross-sectional area. The angle of the nose cone can be 25-30. The angle of the converging wall 139 * of the to one Vertex is elongated, can be 20 - 25 °. The cone I38 can have a length of 20-30 cm. The cooling chamber, i.e. the second ring-shaped kanner 135 *, has ^ lie over its entire length same cross-sectional area.

Fig. 7 shows the cooling device in cross section along the line 7-7 of Fig. 6. Fig. 7 shows the tubes 161 in section and the type and Way in which the same by welds I70 with the outer Wall of the concentric tube I36 are connected. A heat transfer material I7I can be used to fill in the space between the Tubes I6I are used to transfer heat between the to improve hot gases and the coolant

In Figures 8 and 9 is a further embodiment of the cooling device shown. In this embodiment, the cooling of the hot gases takes place mainly through direct contact with the outer wall of the concentric tube 134. To the heat transfer to improve between the pipe 134 and the hot gases, the tube 134 can be provided with a plurality of cooling fins I56 are provided, which protrude in the annular space 135 into the hot gases. *

The cooling device according to the invention causes a rapid Ba cooling of hot media by indirect heat exchange on cooling surfaces. The heat exchanger can be used to cool liquids or gases and / or for heat recovery and for generating steam. When used for cooling a hot gaseous effluent from a furnace for cracking hydrocarbons, the inlet temperature of the gases in the cooling device is approximately 732-899 ⁰ C. In the heat exchanger of the effluent to 38,315 ⁰ C is cooled. The hot gases are fed to the cooling device at a speed of 105-300 m / s, preferably

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at a speed of 150 - 270 m / s. The heat flow at the inlet of the cooling device can be up to 216960 kgcal / h / m and the cooling device can have an average heat flow of about 108480 kgcal / h / m. When operating the device under the pressures given below, about ten to fifteen times the amount of water is circulated for each unit of quantity of steam generated. The apparatus can be constructed and operated so that there is essentially no reduction between the inlet pressure of the hot gas and the outlet pressure of the cooled gas. The pressure decrease of the medium to be cooled can be limited to 0.21 ata and preferably to less than 0.07 ata. The water is introduced into the device at a pressure of 14-140 ata and at a temperature of about 198,335 ° C. Preferably, the cooling water is introduced under a pressure of I05 -.126 ata and with a temperature of about ⁰ C Jl 3327. In the embodiment of the invention, in which the circulation of the coolant is achieved by a thermosiphon effect, the speed of circulation can be self-regulating within certain limits and automatically adjust to changes in the required cooling purpose.

When cooling high temperature hydrocarbon streams, which have some relatively high-boiling components it is necessary to keep the cooling surfaces at a temperature high enough to prevent condensation from forming to prevent high-boiling components and their deposition on the cooling surfaces. But it is also necessary that the Cooling surfaces are cold enough to cover the required rapid cooling of the drainage flow.

Claims

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Claims (8)

Dr. Ing. E. BERKENFELD ·. Dipl.-Ing. H. BERKENFELD, patent attorneys, Cologne system on the submission of Sept. 8, 1969 File number Named.Aniti ^ tone & Webster Engineering Corp, Claims j DJ heat exchanger with a central chamber and a ^ -first and a second annular chamber, the central chamber having an inlet at one end and the other end of the central chamber communicating with the first annular chamber, the w first annular chamber Has outlet at the end opposite the end that is connected to the central chamber, and the second annular chamber has an inlet at one end and an outlet at the other end according to patent application P 15 51 536.3-13, characterized in that the inlet channel (4o) is one widening inlet section (4l) for the passage of the hot fluid and means (19,2o, 33, etc.) for Cooling of the hot fluid are provided. 2) Heat exchanger according to claim 1, characterized in that the widening inlet section (4l) is tubular and has an opening angle of more than H ° . 3) heat exchanger according to claim 1, characterized in that that the widening inlet section (4l) is tubular and has an opening angle between 4 ° and 7 °. ¹ OV / heat exchanger according to claim 1, characterized in that the opening angle of the inlet section ( ¹ H) is 5 °. 5) heat exchanger according to claim 2, characterized in that the channel for the passage of the hot fluid is a centrally arranged tube and the device for cooling the hot fluid passing through is one by one cooling chamber arranged around the channel. st 27 / 1O 009840/1112 -i- 6) heat exchanger according to claim 2, characterized in that that the channel for the passage of the hot fluid is a centrally arranged tube and the device for Cooling of the hot fluid passing through the tube is an annular tube arrangement that is in direct contact stands with the outer surface of the centrally arranged chamber. 7) Heat exchanger according to claim 6, characterized in that cooling lines are arranged at each end of the heat exchanger are and the annular tube array, which are in direct contact with the surface of the centrically arranged Chamber is connected to these lines. 8) Heat exchanger according to claim 7, characterized in that the cooling lines connected to the annular tube arrangement are connected, have an annular shape. 9). Heat exchanger according to claim 5, characterized in that the cooling chamber has a coolant inlet which is arranged in the immediate vicinity of the inlet of the centrally arranged chamber for the hot fluid, and an outlet which is in the immediate vicinity of the outlet of the centrally arranged chamber for the hot fluid is arranged. 10) heat exchanger according to claim 9, characterized in that that the coolant chamber surrounds the entire centrally arranged chamber for the hot fluid. 11) heat exchanger according to claim 1, characterized in that that the channel for the hot fluid is annular. 12) Heat exchanger according to claim 11, characterized in that the abutment _{v of} the cross-sectional area of the widening inlet section is equivalent to the increase in the cross-sectional area per unit length of a conical tube which has an opening angle of more than ^l \ , st 27/10 0098 AO / 1 1 12 -2- 13) Heat exchanger according to claim 11, characterized in that the increase in the cross-sectional area of the widen Inlet section is equivalent to the increase in cross-sectional area per unit length of a conical tube, the one has an opening angle between 4 ° and 7 °. lh) Heat exchanger according to claim 11, characterized in that the increase in the cross-sectional area of the widening inlet section is equivalent to the increase in the cross-sectional area per unit length of a conical tube which has an opening angle of 5 °. 15) Heat exchanger according to claim 12, characterized in that the device for cooling the passing through the Rinkkanal hot fluid is a cooling channel that is concentric with and within the inner wall of the annular channel is arranged. 16) heat exchanger according to claim 15, characterized in that that the cooling channel, which is arranged concentrically to and within the inner wall of the annular channel, # consists of a tubular there is central cooling chamber, which is arranged axially in the heat exchanger, the central cooling chamber has an inlet at one End and an outlet at the other end, one annular cooling chamber through the outer wall of the tubular central chamber and the inner wall of the annular through ■ passage channel is formed for the hot fluid, and there is a connection between the tubular central chamber and the annular cooling chamber. 17) Heat exchanger according to claim 16, characterized in that the widening inlet for the annular passage channel is formed by a cone extending from the end of the inner wall of the annular passage channel in the vicinity of the Inlet for the hot fluid goes out, and through a converging wall enclosing the cone, wherein the converging wall from the outer wall of the annular passage channel to the inlet for the hot fluid ^s * 27 / 1O 00 98A0 / 1 1 12 -3- runs. 18) Heat exchanger according to claim 17, characterized in that the cone has an opening angle of 25 ° to 3o ° and the converging wall that extends from the outer wall of the annular passage channel and surrounds the cone, has an opening angle of 2o ° to 25 °. 19) Heat exchanger according to claim 15, characterized in that a cooling device is provided which the outer wall enclosing the annular passage channel for the hot fluid. 20) heat exchanger according to claim 19, characterized in that that the cooling device which encloses the outer wall of the annular passage channel for the hot fluid, is a cooling chamber. / 21) Heat exchanger according to claim 2o, characterized in that cooling fins from the outer wall of the annular passage channel for the hot fluid protrude into the outer cooling chamber, 22) Procedure for Cooling Hot Fluids in a heat exchanger according to claims 1 to 2.1, characterized in that the hot fluid in itself erte? widening tube is introduced that the fluid is introduced from the expanding cooling section into a section with a continuous cross-sectional shape, and that the fluid passing through the portion with the continuous cross-sectional shape is cooled. 23) Method according to claim 22, characterized in that the hot dmchtretende through the widening tube Fluid is cooled indirectly. 2k) Method according to claim 22, characterized in that the outlet pressure of the cooled fluid is practically ^{st 2} 7 / l ° 0 0 9 8 4 0/1 112. -.--. - * - _{c is} exactly the same as vrie is the inlet pressure at the widening inlet section, 25) Method according to claim 2k , characterized in that the hot fluid in the widening inlet section is subjected to a gradual increase in the cross-sectional area at an opening angle between 4 ° and lo °, 26) Method according to claim 24, characterized in that the hot fluid in the widening inlet portion undergoes a gradual increase in cross-sectional area exposed to an opening angle of 5 °. 27) Method according to claim 25, characterized in that the hot fluid at a speed of 108 m / sec up to 305 m / sec is introduced into the widening inlet section and this speed is gradually reduced so that the pressure drop caused by frictional losses is practically equal to the pressure increase caused by conversion kinetic energy arises in static pressure, 23) Method according to claim 27, characterized in that the coolant is water, which is indirectly with the hot fluids at a pressure of l4.1 kp / cm absolute to l4l kp / cm at-eiHem-Spfeiek-veR and a temperature of 198 ⁰ C to 335 ° C is brought into contact, 29) Method according to claim 28, characterized in that the emerging hot fluid the effluent of a hydrocarbon conversion process heieß gas which is introduced into the flared inlet at a rate of about 2I0 to 24o m / sec and with a temperature between about 732 ⁰ C and 899 ° C, and that the gas by about 38 ⁰ C to 316 ⁰ C in about 1 to 3o good milliseconds quickly to about. 649 ⁰ C..-_,., - is cooled down to 76o ° C. 30) The method according to claim 2 ^ characterized in that the hot dripping off Gai au »a method for producing UW / U 000840/1112 -5- - BATH ORIGINAL originates from olefins and that the hot gases in the expanding Inlet at a temperature of about 81-16 ° C to 899 ° C and by about 38 ° C to 36 ° C in about 5 to 15 milliseconds be cooled down quickly,