EP0290813A1 - Echangeur de chaleur, en particulier pour refroidir des gaz de crackage - Google Patents
Echangeur de chaleur, en particulier pour refroidir des gaz de crackage Download PDFInfo
- Publication number
- EP0290813A1 EP0290813A1 EP88106024A EP88106024A EP0290813A1 EP 0290813 A1 EP0290813 A1 EP 0290813A1 EP 88106024 A EP88106024 A EP 88106024A EP 88106024 A EP88106024 A EP 88106024A EP 0290813 A1 EP0290813 A1 EP 0290813A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- sleeve
- tube
- heat exchanger
- gas
- cooling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000007789 gas Substances 0.000 title claims abstract description 32
- 238000001816 cooling Methods 0.000 title claims abstract description 18
- 239000002826 coolant Substances 0.000 claims abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000009835 boiling Methods 0.000 claims abstract description 5
- 239000000571 coke Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 4
- 238000001704 evaporation Methods 0.000 description 4
- 238000009736 wetting Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 229930195733 hydrocarbon Natural products 0.000 description 3
- 150000002430 hydrocarbons Chemical class 0.000 description 3
- 230000005494 condensation Effects 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000004992 fission Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000005336 cracking Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000004227 thermal cracking Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/22—Arrangements for directing heat-exchange media into successive compartments, e.g. arrangements of guide plates
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/02—Header boxes; End plates
- F28F9/0229—Double end plates; Single end plates with hollow spaces
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
- F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
- F28D2021/0075—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for syngas or cracked gas cooling systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/22—Arrangements for directing heat-exchange media into successive compartments, e.g. arrangements of guide plates
- F28F2009/222—Particular guide plates, baffles or deflectors, e.g. having particular orientation relative to an elongated casing or conduit
- F28F2009/226—Transversal partitions
Definitions
- the invention relates to a heat exchanger, in particular for cooling cracked gases, according to the preamble of claim 1.
- the fission gases formed by thermal cracking of hydrocarbons are cooled very quickly to stabilize their molecular composition. This is done by indirect heat transfer from the cracked gas to the heat-absorbing medium in cracked gas coolers.
- the cracked gas is passed through pipes which are surrounded by evaporating water as a cooling medium.
- the evaporating water provides intensive cooling of the pipes, which means that the wall temperature is relatively low and is only slightly above the temperature of the evaporating water.
- the cracked gas is a mixture of hydrocarbons of different molecular weights and partial pressures.
- the condensation temperature can be fallen below for some of the components. As a result, these components are precipitated on the pipe wall in the area of low temperatures and a so-called coke layer is built up.
- This coke layer increases the flow resistance, which increases the gas pressure in the upstream cracking furnace. This results in poorer fission gas yield, a further increase in the coke layer, rising gas outlet temperature and lower steam generation. After a certain operating time, the cracked gas cooler must be taken out of operation to remove the coke layer.
- the invention has for its object to design the generic heat exchanger such that the cooling effect on outlet-side end of the gas-carrying pipes is reduced to the extent that the risk of the formation of a coke layer is largely avoided.
- the wetting of the rear pipe end with cooling medium is reduced. This makes the cooling effect less intense, so that the temperature on the inner wall of the gas-carrying pipe is above the condensation temperature of the cracked gas components.
- the degree of cooling can be changed by changing the gap width between the gas-carrying pipe and the surrounding sleeve pipe and by changing the thickness or density of the wire mesh, and the heat exchanger can thus be adapted to the operating requirements.
- the heat exchanger shown is of a standing type and is used in particular for cooling cracked gas with the help of evaporating water under excess pressure. It consists of a tube bundle composed of individual tubes 1, through which the gas to be cooled flows and which are surrounded by a jacket 2. The tubes 1 are held in two tube plates 3, 4, to which a gas inlet chamber 5 and a gas outlet chamber 6 are connected.
- the thin tube plate 3 on the gas inlet side is on the Supported gas inlet chamber 5 side supported by a support plate 7 which is arranged to form a space 8 at a distance from the thin tube plate 3. Between the thin tube plate 3 and the support plate 7, support fingers 9 are provided distributed over the cross section and are molded onto the support plate 7.
- the tubes 1 each penetrate loosely through the support plate 7, forming an annular gap.
- the thin tube plate 3 is connected to an outer ring jacket 10 and the support plate 7 is connected to an inner ring jacket 11.
- the ring jackets 10, 11 are connected to one another and delimit an annular chamber 12 into which an inlet connection 13 for the supply of the water serving as a cooling medium.
- the upper part of the jacket 2 is provided with an outlet connection 14 for the removal of the cooling medium.
- the sleeve consists of a sleeve tube 15 which is open on both sides and which surrounds the tube 1 at a distance, forming an annular gap.
- the sleeve tube 15 is supported on the tube 1 via cams 16.
- the sleeve tubes 15 are held in locking washers 17, which are arranged within the jacket 2 perpendicular to the axis thereof and which are intended to prevent the tubes 1 from vibrating.
- the length of the sleeve tube 15 is adapted to the operating requirements and ends shortly before the tube plate 4 lying on the gas outlet side.
- the width of the annular gap between the tube 1 and the sleeve tube 15 is dimensioned so large that the boiling water present in the interior of the jacket 1 is prevented from flowing into the annular gap in an amount sufficient for complete wetting.
- the resulting reduced or prevented wetting of the tube 1 with boiling water causes a reduced heat transfer from the heat-emitting to the heat-absorbing medium and thereby the desired less intensive cooling.
- This less intensive cooling causes a higher pipe wall temperature, which means that no or fewer hydrocarbons condense. The result is that coke formation is prevented or at least reduced.
- the reduction in the cooling effect can be influenced by changing the gap width. Furthermore, openings 18 can be provided in the wall of the sleeve tube 15, through which boiling water can penetrate into the annular gap and thus increase the cooling effect again.
- the invention can be used both in shell-and-tube heat exchangers (FIGS. 1 and 2) and in double-tube heat exchangers.
- a section of such a double tube heat exchanger is shown in FIG. 3.
- each gas-carrying pipe 1 is surrounded by an outer pipe 19 to form an annular space.
- the annular space is connected to an inlet and an outlet chamber 20, which is common to a number of double pipes.
- a gas-carrying pipe 1 facing the outlet chamber 20 can, as described, be enclosed by a sleeve tube 15 which ends shortly before the outlet chamber 20 or protrudes a little into it.
- 3 shows a different type of sheathing of the gas-carrying pipe 1, which can optionally also be used in the shell-and-tube heat exchanger according to FIGS. 1 and 2.
- This sheath consists of a wire mesh 21, which is drawn like a sock over the tube 1.
- the wire mesh 21 reduces wetting of the gas-carrying pipe 1 on the endangered pipe length in the same way as the sleeve pipe 15.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE3715713A DE3715713C1 (de) | 1987-05-12 | 1987-05-12 | Waermetauscher insbesondere zum Kuehlen von Spaltgasen |
DE3715713 | 1987-05-12 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0290813A1 true EP0290813A1 (fr) | 1988-11-17 |
EP0290813B1 EP0290813B1 (fr) | 1991-03-06 |
Family
ID=6327298
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP88106024A Expired - Lifetime EP0290813B1 (fr) | 1987-05-12 | 1988-04-15 | Echangeur de chaleur, en particulier pour refroidir des gaz de crackage |
Country Status (4)
Country | Link |
---|---|
US (1) | US4858684A (fr) |
EP (1) | EP0290813B1 (fr) |
JP (1) | JPS63297995A (fr) |
DE (2) | DE3715713C1 (fr) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3614053A1 (fr) | 2018-06-08 | 2020-02-26 | BSH Hausgeräte GmbH | Dispositif formant une hotte aspirante et appareil combiné pourvu d'un dispositif formant une hotte aspirante et d'une table de cuisson |
Families Citing this family (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3822808C2 (de) * | 1988-07-06 | 1993-12-23 | Balcke Duerr Ag | Wärmetauscher mit zwischen zwei Rohrplatten angeordneten Wärmetauscherrohren |
DE3913731A1 (de) * | 1989-04-26 | 1990-10-31 | Borsig Gmbh | Waermetauscher zum kuehlen von spaltgas |
DE3930205A1 (de) * | 1989-09-09 | 1991-03-14 | Borsig Babcock Ag | Rohrbuendel-waermetauscher |
DE4404068C1 (de) * | 1994-02-09 | 1995-08-17 | Wolfgang Engelhardt | Wärmetauscher |
DE4407594A1 (de) * | 1994-03-08 | 1995-09-14 | Borsig Babcock Ag | Wärmetauscher zum Kühlen von heißem Reaktionsgas |
MY114772A (en) * | 1994-07-05 | 2003-01-31 | Shell Int Research | Apparatus for cooling hot gas |
DE4445687A1 (de) * | 1994-12-21 | 1996-06-27 | Borsig Babcock Ag | Wärmetauscher zum Kühlen von Spaltgas |
CA2191379A1 (fr) * | 1995-11-28 | 1997-05-29 | Cuddalore Padmanaban Natarajan | Echangeur de chaleur pour applications haute temperature |
GB2319333B (en) * | 1996-11-11 | 2000-08-09 | Usui Kokusai Sangyo Kk | EGR Gas cooling apparatus |
DE60324626D1 (de) * | 2002-04-23 | 2008-12-24 | Exxonmobil Res & Eng Co | Wärmetauscher mit schwimmendem Endkasten |
US20050135978A1 (en) * | 2003-10-14 | 2005-06-23 | Mourad Hamedi | Method and apparatus for optimizing throughput in a trickle bed reactor |
CN101818840B (zh) * | 2006-01-19 | 2013-05-29 | 东洋制罐株式会社 | 联结器以及燃料电池用的燃料盒 |
DE102006003317B4 (de) | 2006-01-23 | 2008-10-02 | Alstom Technology Ltd. | Rohrbündel-Wärmetauscher |
US9557119B2 (en) | 2009-05-08 | 2017-01-31 | Arvos Inc. | Heat transfer sheet for rotary regenerative heat exchanger |
US8672021B2 (en) | 2010-02-12 | 2014-03-18 | Alfred N. Montestruc, III | Simplified flow shell and tube type heat exchanger for transfer line exchangers and like applications |
RU2451888C2 (ru) * | 2010-05-26 | 2012-05-27 | Российская Федерация, от имени которой выступает Министерство промышленности и торговли Российской Федерации (Минпромторг России) | Вертикальный кожухотрубчатый испаритель с перегревателем |
PL216290B1 (pl) * | 2010-10-01 | 2014-03-31 | Aic Społka Akcyjna | Wymiennik ciepła |
US8813688B2 (en) * | 2010-12-01 | 2014-08-26 | Aic S.A. | Heat exchanger |
US9200853B2 (en) | 2012-08-23 | 2015-12-01 | Arvos Technology Limited | Heat transfer assembly for rotary regenerative preheater |
US11149945B2 (en) * | 2013-05-31 | 2021-10-19 | Corrosion Monitoring Service, Inc. | Corrosion resistant air preheater with lined tubes |
JP5941878B2 (ja) * | 2013-07-25 | 2016-06-29 | 株式会社ユタカ技研 | 熱交換器及び熱交換デバイス |
US10175006B2 (en) | 2013-11-25 | 2019-01-08 | Arvos Ljungstrom Llc | Heat transfer elements for a closed channel rotary regenerative air preheater |
US10094626B2 (en) | 2015-10-07 | 2018-10-09 | Arvos Ljungstrom Llc | Alternating notch configuration for spacing heat transfer sheets |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1782435A (en) * | 1926-11-09 | 1930-11-25 | Gen Chemical Corp | Apparatus for cooling fluids |
GB969036A (en) * | 1960-09-21 | 1964-09-09 | Fives Penhoet | Improvements in or relating to tubular heat exchange apparatus |
FR1569319A (fr) * | 1967-06-20 | 1969-05-30 | ||
DE2218489A1 (de) * | 1972-04-17 | 1973-10-31 | Wmf Wuerttemberg Metallwaren | Verdampferrohr |
US3802497A (en) * | 1970-02-23 | 1974-04-09 | J Kummel | Heat exchanger for cooling gases |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3071540A (en) * | 1959-10-27 | 1963-01-01 | Kellogg M W Co | Oil feed system for fluid catalytic cracking unit |
JPS52112607A (en) * | 1976-03-09 | 1977-09-21 | Agency Of Ind Science & Technol | Reformers |
DE2913748C2 (de) * | 1979-04-03 | 1983-09-29 | Borsig Gmbh, 1000 Berlin | Rohrbündelwärmetauscher zum Kühlen schlackenhaltiger Heißgase der Kohlevergasung |
FR2458783B1 (fr) * | 1979-06-11 | 1987-01-16 | Westinghouse Electric Corp | Tubes de transfert de chaleur comportant des moyens pour limiter le flux calorifique |
US4294312A (en) * | 1979-11-09 | 1981-10-13 | Borsig Gmbh | Tube-bundle heat exchanger for cooling a medium having a high inlet temperature |
US4537249A (en) * | 1981-02-02 | 1985-08-27 | The United States Of America As Represented By The United States Department Of Energy | Heat flux limiting sleeves |
DE3411795A1 (de) * | 1984-03-30 | 1985-10-03 | Borsig Gmbh, 1000 Berlin | Verfahren zum betreiben von rohrbuendelwaermeaustauschern zum kuehlen von gasen |
DE3429522C1 (de) * | 1984-08-10 | 1985-11-14 | Uhde Gmbh, 4600 Dortmund | Reaktionsrohrsystem eines Roehrenspaltofens |
DE3532413A1 (de) * | 1985-09-11 | 1987-03-12 | Uhde Gmbh | Vorrichtung zur erzeugung von synthesegas |
DE3533219C1 (de) * | 1985-09-18 | 1986-11-13 | Borsig Gmbh, 1000 Berlin | Rohrbuendelwaermetauscher |
-
1987
- 1987-05-12 DE DE3715713A patent/DE3715713C1/de not_active Expired - Lifetime
-
1988
- 1988-04-15 EP EP88106024A patent/EP0290813B1/fr not_active Expired - Lifetime
- 1988-04-15 DE DE8888106024T patent/DE3861898D1/de not_active Expired - Lifetime
- 1988-04-28 JP JP63107432A patent/JPS63297995A/ja active Pending
- 1988-05-11 US US07/193,116 patent/US4858684A/en not_active Expired - Fee Related
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1782435A (en) * | 1926-11-09 | 1930-11-25 | Gen Chemical Corp | Apparatus for cooling fluids |
GB969036A (en) * | 1960-09-21 | 1964-09-09 | Fives Penhoet | Improvements in or relating to tubular heat exchange apparatus |
FR1569319A (fr) * | 1967-06-20 | 1969-05-30 | ||
US3802497A (en) * | 1970-02-23 | 1974-04-09 | J Kummel | Heat exchanger for cooling gases |
DE2218489A1 (de) * | 1972-04-17 | 1973-10-31 | Wmf Wuerttemberg Metallwaren | Verdampferrohr |
Non-Patent Citations (1)
Title |
---|
PATENT ABSTRACTS OF JAPAN, Band 10, Nr. 163 (M-487)[2219], 11. Juni 1986; & JP-A-61 015 088 (MATSUSHITA DENKI SANGYO K.K.) 23-01-1986 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3614053A1 (fr) | 2018-06-08 | 2020-02-26 | BSH Hausgeräte GmbH | Dispositif formant une hotte aspirante et appareil combiné pourvu d'un dispositif formant une hotte aspirante et d'une table de cuisson |
Also Published As
Publication number | Publication date |
---|---|
US4858684A (en) | 1989-08-22 |
DE3861898D1 (de) | 1991-04-11 |
DE3715713C1 (de) | 1988-07-21 |
JPS63297995A (ja) | 1988-12-05 |
EP0290813B1 (fr) | 1991-03-06 |
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