EP0519230A1 - Pyrolysis heater - Google Patents
Pyrolysis heater Download PDFInfo
- Publication number
- EP0519230A1 EP0519230A1 EP92108658A EP92108658A EP0519230A1 EP 0519230 A1 EP0519230 A1 EP 0519230A1 EP 92108658 A EP92108658 A EP 92108658A EP 92108658 A EP92108658 A EP 92108658A EP 0519230 A1 EP0519230 A1 EP 0519230A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- tubes
- heater
- radiant section
- section
- radiant
- 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.)
- Withdrawn
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G9/00—Thermal non-catalytic cracking, in the absence of hydrogen, of hydrocarbon oils
- C10G9/14—Thermal non-catalytic cracking, in the absence of hydrogen, of hydrocarbon oils in pipes or coils with or without auxiliary means, e.g. digesters, soaking drums, expansion means
- C10G9/18—Apparatus
- C10G9/20—Tube furnaces
Definitions
- This invention relates to an improved pyrolysis heater for the breaking apart of complex hydrocarbon molecules into simpler units.
- a pyrolysis heater which includes a radiant heating section and a convection heating section, positioned above and offset from the radiant heating section, which is in gas flow communication with the radiant heating section.
- the radiant heating section is provided with at least two rows of vertical tubes, with the tubes in each row being in a single plane which is perpendicular to a vertical plane through the longitudinal axis of the convection section.
- the radiant section is provided with radiant burners positioned in the floor thereof, with each row of tubes having one row of burners on each side of the row.
- the radiant section is preferably shaped in a manner such that the width of the radiant section is substantially equal to the length of the radiant section; i.e. , the width is from 80% to 120% of the length of the radiant section and preferably 90% to 110% of the length.
- the height of the radiant section is also substantially equal to the length thereof whereby the radiant section has essentially a cube shape.
- each row may be arranged to provide one or more passes for a feed introduced into the tubes (tubes which provide one or more passes are referred to as a "coil") and each row of tubes may include one or more coils.
- two tubes in a single row are interconnected to form two vertical passes through the radiant section (a double pass coil) and such row can include a plurality of double pass coils.
- three or more tubes may be interconnected to provide for three or more passes through the radiant heating section and each row may have one, two or more of such coils.
- a plurality of tubes providing a first pass may be interconnected with a single tube forming a second pass.
- the tubes in each row may have the same inside diameter or different inside diameters.
- the coils in the radiant section are designed to provide for short residence time cracking to produce ethylene (residence time of less than 0.5 sec).
- the residence time is not less than 0.07 second, with the coil preferably being designed for a residence time of no greater than 0.2 second.
- the total length of a coil in the radiant section is generlaly at least 30 feet and generally does not exceed 80 feet and the coil may be formed from one or more tubes of a suitable length.
- the overall length of the coil, the inside diameter and other conditions are coordinated to provide a short residence time as hereinabove described.
- the height of the heater (direction parallel to tubes) is from about 20 to 45 feet, with the length and width of the heater having related dimensions, as hereinabove described.
- the radiant section has at least sixteen coils therein (each coil can be formed from one, two or more tubes).
- the vertical tubes used in teh pyrolysis heater generally have a nominal inside diameter of from 1" to 4" with 1" to 2" being preferred for theinlet tubes.
- the inside of the tubes may be smooth or may include fins.
- the outlet tubes of the coil can have larger diameters.
- the tubes when arranged into coils for providing multiple passes can be arranged in a manner such that a plurality of tubes are each provided with feed, with such plurality of tubes providing a single pass through the radiant section and exiting into a manifold conected to a single tube of a larger diameter for providing a second pass through the radiant section.
- the coil outlets are preferably connected to a suitable transfer line exchanger for rapidly cooling the effluent to below cracking temperatures.
- the temperature of the effluent withdrawn from the coils is in the order of 1400°F to 1750°F.
- the feed to the coils is generally diluted with steam.
- a pyrolysis heater generally designated as 10 comprised of a radiant section, generally designated as 11 and a convection section 12 above and laterally offset from radiant section 11 with the interior of the radiant section 11 being in gas flow communication with the convection section 12 through a horizontal passage 13.
- the radiant section 11 includes a plurality of rows of vertical tubes 14, with each row of tubes 14 being in a single plane substantially perpendicular to a plane through the longitudinal axis of the convection section 12. As shown in Figure 1 there are four rows of vertical tubes 14.
- the radiant section includes a plurality of radiant burners 15 which are positioned in the floor of the radiant section 11.
- the burners 15 are arranged in rows parallel to the rows of vertical tubes 14, and each row of tubes 14 is provided with two rows of floor burners 15 with one row of burners 15 being on each side of a row of vertical tubes 14.
- the burners on each side of the vertical tubes are preferably spaced from the vertical tubes by the same distance.
- the vertical tubes 14 in each row are interconnected to provide radiant coils for pyrolyzing a feed.
- the tubes 14 in each row are arranged to provide two passes for each feed stream of hydrocarbon to be pyrolyzed. More particularly, a plurality of tubes 14a, in one row are connected to a horizontal manifold 21 which is connected to a vertical tube 14b having an inside diameter greater than the tubes 14a. The upper ends of tubes 14a are connected to an inlet manifold 22 for providing a hydrocarbon feed to the tubes 14a and the tops of tubes 14b are connected to a transfer line exchanger 23 for receiving pyrolysis effluent.
- hydrocarbon to be pyrolyzed is introduced into the tops of tubes 14a, passes downwardly through tubes 14a into manifold 21 and then upwardly through tubes 14b for introduction into a transfer line exchanger 23.
- a feed to be pyrolyzed may be preheated in convection tubes 24 located in convection section 12, with the preheated feed being introduced into tubes 14a through manifolds 22.
- a single row of vertical tubes may be divided into two sets of tubes, with each set forming one coil.
- Each coil is comprised of twelve tubes 14a providing a first pass, with each of the twelve tubes 14a being connected to a single tube 14b which provides the second pass.
- the height, length and width of the radiant section 11 are equal to each other.
- the heater is shown with a single radiant section the heater could be constructed with two radiant sections, each of which is in gas flow communication with the convection section.
Landscapes
- Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
Pyrolysis heater 10 in which vertical tubes 14 in the radiant section are provided in a plurality of parallel rows, with each row being in a plane perpendicular to a plane through the longitudinal axis of the convection section of the heater. The radiant section is preferably in the form of cube and the tubes are heated by floor burners 15 in rows parallel to the tubes.
Description
- This invention relates to an improved pyrolysis heater for the breaking apart of complex hydrocarbon molecules into simpler units.
- An Example of a pyrolysis heater in the prior art is U.S. Patent No. 3,274,978 to E.H. Palchik et al., which includes two parallel radiant heating zones, with a single convection zone disposed above the radiant heating zones. The plurality of vertically disposed coils are heated by a plurality of vertical rows of high intensity radiant burners on each wall of the radiant heating zones.
- In accordance with an aspect of the present invention, there is provided a pyrolysis heater which includes a radiant heating section and a convection heating section, positioned above and offset from the radiant heating section, which is in gas flow communication with the radiant heating section.
- The radiant heating section is provided with at least two rows of vertical tubes, with the tubes in each row being in a single plane which is perpendicular to a vertical plane through the longitudinal axis of the convection section.
- The radiant section is provided with radiant burners positioned in the floor thereof, with each row of tubes having one row of burners on each side of the row.
- The radiant section is preferably shaped in a manner such that the width of the radiant section is substantially equal to the length of the radiant section; i.e. , the width is from 80% to 120% of the length of the radiant section and preferably 90% to 110% of the length.
- In a particularly preferred embodiment, the height of the radiant section is also substantially equal to the length thereof whereby the radiant section has essentially a cube shape.
- The tubes in each row may be arranged to provide one or more passes for a feed introduced into the tubes (tubes which provide one or more passes are referred to as a "coil") and each row of tubes may include one or more coils.
- Thus, for example, in one embodiment, two tubes in a single row are interconnected to form two vertical passes through the radiant section (a double pass coil) and such row can include a plurality of double pass coils. Similarly three or more tubes may be interconnected to provide for three or more passes through the radiant heating section and each row may have one, two or more of such coils. In forming a coil having two or more pases, a plurality of tubes providing a first pass may be interconnected with a single tube forming a second pass.
- The tubes in each row may have the same inside diameter or different inside diameters.
- The coils in the radiant section are designed to provide for short residence time cracking to produce ethylene (residence time of less than 0.5 sec). In general, the residence time is not less than 0.07 second, with the coil preferably being designed for a residence time of no greater than 0.2 second.
- The total length of a coil in the radiant section is generlaly at least 30 feet and generally does not exceed 80 feet and the coil may be formed from one or more tubes of a suitable length. The overall length of the coil, the inside diameter and other conditions are coordinated to provide a short residence time as hereinabove described.
- In accordance with a preferred embodiment, the height of the heater (direction parallel to tubes) is from about 20 to 45 feet, with the length and width of the heater having related dimensions, as hereinabove described.
- In a particularly preferred embodiment, the radiant section has at least sixteen coils therein (each coil can be formed from one, two or more tubes).
- The vertical tubes used in teh pyrolysis heater generally have a nominal inside diameter of from 1" to 4" with 1" to 2" being preferred for theinlet tubes. The inside of the tubes may be smooth or may include fins. The outlet tubes of the coil can have larger diameters.
- The tubes when arranged into coils for providing multiple passes can be arranged in a manner such that a plurality of tubes are each provided with feed, with such plurality of tubes providing a single pass through the radiant section and exiting into a manifold conected to a single tube of a larger diameter for providing a second pass through the radiant section.
- The invention shall be further described with respect to an embodiment illustrated in the drawings wherein:
- Figure 1 is a simplified schematic of a pyrolysis heater; and
- Figure 2 is a simplified schematic of a single row of tubes in the pyrolysis heater.
- The coil outlets are preferably connected to a suitable transfer line exchanger for rapidly cooling the effluent to below cracking temperatures.
- In preferred embodiments, the temperature of the effluent withdrawn from the coils is in the order of 1400°F to 1750°F.
- As known in the art, the feed to the coils is generally diluted with steam.
- Referring now to the drawings, there is shown a pyrolysis heater, generally designated as 10 comprised of a radiant section, generally designated as 11 and a
convection section 12 above and laterally offset from radiant section 11 with the interior of the radiant section 11 being in gas flow communication with theconvection section 12 through ahorizontal passage 13. - The radiant section 11 includes a plurality of rows of
vertical tubes 14, with each row oftubes 14 being in a single plane substantially perpendicular to a plane through the longitudinal axis of theconvection section 12. As shown in Figure 1 there are four rows ofvertical tubes 14. - The radiant section includes a plurality of
radiant burners 15 which are positioned in the floor of the radiant section 11. Theburners 15 are arranged in rows parallel to the rows ofvertical tubes 14, and each row oftubes 14 is provided with two rows offloor burners 15 with one row ofburners 15 being on each side of a row ofvertical tubes 14. The burners on each side of the vertical tubes are preferably spaced from the vertical tubes by the same distance. Thevertical tubes 14 in each row are interconnected to provide radiant coils for pyrolyzing a feed. - As shown in Figures 1 and 2, the
tubes 14 in each row are arranged to provide two passes for each feed stream of hydrocarbon to be pyrolyzed. More particularly, a plurality oftubes 14a, in one row are connected to ahorizontal manifold 21 which is connected to avertical tube 14b having an inside diameter greater than thetubes 14a. The upper ends oftubes 14a are connected to aninlet manifold 22 for providing a hydrocarbon feed to thetubes 14a and the tops oftubes 14b are connected to atransfer line exchanger 23 for receiving pyrolysis effluent. Thus, as shown, hydrocarbon to be pyrolyzed is introduced into the tops oftubes 14a, passes downwardly throughtubes 14a intomanifold 21 and then upwardly throughtubes 14b for introduction into atransfer line exchanger 23. As known in the art, a feed to be pyrolyzed may be preheated inconvection tubes 24 located inconvection section 12, with the preheated feed being introduced intotubes 14a throughmanifolds 22. - Thus, for example, a single row of vertical tubes may be divided into two sets of tubes, with each set forming one coil. Each coil is comprised of twelve
tubes 14a providing a first pass, with each of the twelvetubes 14a being connected to asingle tube 14b which provides the second pass. - In a preferred embodiment, the height, length and width of the radiant section 11 are equal to each other.
- Although the heater is shown with a single radiant section the heater could be constructed with two radiant sections, each of which is in gas flow communication with the convection section.
Claims (8)
- A pyrolysis heater, comprising:
a radiant section; convection section in gas flow communication with the radiant section; at least two rows of vertical tubes positioned in the radiant section, said radiant section containing at least two rows of vertical tubes being parallel to each other in a plane perpendicular to a plane through the longitudinal axis of the convection section, a plurality of radiant burners positioned in the floor of the radiant section in rows parallel to the vertical tubes, each row of vertical tubes having a first row of burners on one side of the vertical tubes and a second row of burners on a second side of the vertical tubes, said radiant section having a width which is substantially equal to the length of the radiant section. - The heater of Claim 1 wherein the tubes in a single row are interconnected to form a plurality of coils.
- The heater of Claim 2 wherein the tubes in a coil have different diameters.
- The heater of Claim 3 wherein the tubes in a coil are interconnected to provide two vertical passes through the radiant section.
- The heater of Claim 3 wherein a coil has a length of from 30 feet to 80 feet.
- The heater of Claim 2 wherein the height of the radiant section is substantially equal to the width thereof.
- The heater of Claim 6 wherein a coil has a length of from 30 feet to 80 feet.
- The heater of Claim 7 wherein the tubes in a coil are interconnected to provide two vertical passes through the radiant section.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US71623091A | 1991-06-17 | 1991-06-17 | |
US716230 | 1991-06-17 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0519230A1 true EP0519230A1 (en) | 1992-12-23 |
Family
ID=24877251
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP92108658A Withdrawn EP0519230A1 (en) | 1991-06-17 | 1992-05-22 | Pyrolysis heater |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0519230A1 (en) |
JP (1) | JPH0613710B2 (en) |
KR (1) | KR950005680B1 (en) |
CN (1) | CN1026120C (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2760467A1 (en) * | 1997-03-04 | 1998-09-11 | Procedes Petroliers Petrochim | Steam cracking furnace, used to make ethylene or propylene |
FR2761371A1 (en) * | 1997-03-28 | 1998-10-02 | Procedes Petroliers Petrochim | Tubular furnace for cracking hydrocarbon(s) in the presence of steam |
WO2002100982A1 (en) * | 2001-06-13 | 2002-12-19 | Abb Lummus Global Inc. | Pyrolysis heater with paired burner zoned firing system |
EP1295930A1 (en) * | 2001-09-19 | 2003-03-26 | China Petroleum & Chemical Corporation | Pyrolysis furnace with new type radiant tubes arrangement and method of its operation and usage |
WO2003087268A2 (en) * | 2002-04-10 | 2003-10-23 | Abb Lummus Global Inc. | Cracking furnace with more uniform heating |
EP1417098A1 (en) * | 2001-04-24 | 2004-05-12 | ABB Lummus Global Inc. | Pyrolysis heater |
US8490581B2 (en) | 2006-06-15 | 2013-07-23 | Exxonmobil Research And Engineering Company | Advanced fired heater unit for use in refinery and petro-chemical applications |
EP2949728A1 (en) | 2014-05-28 | 2015-12-02 | Wison Engineering Ltd. | Ethylene cracking furnace |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU7487198A (en) * | 1997-05-13 | 1998-12-08 | Stone & Webster Engineering Corporation | Cracking furnace with radiant heating tubes |
CN101723784B (en) | 2008-10-16 | 2012-12-26 | 中国石油化工股份有限公司 | Ethylene cracking furnace |
MY177140A (en) | 2011-07-28 | 2020-09-08 | China Petroleum & Chem Corp | Ethylene cracking furnace |
CN104140841B (en) * | 2013-05-07 | 2016-05-11 | 中国石化工程建设有限公司 | A kind of ethane cracking furnace |
CN110835547A (en) * | 2018-08-16 | 2020-02-25 | 中国石化工程建设有限公司 | Ethylene cracking furnace |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3274978A (en) * | 1964-02-24 | 1966-09-27 | Lummus Co | Vertical tube fluid heater |
GB1194733A (en) * | 1966-08-26 | 1970-06-10 | Pullman Inc | Furnace for Heating Reactant Fluids |
US3630850A (en) * | 1968-12-02 | 1971-12-28 | Shell Oil Co | Cracking furnace with burners engaging mirror image coiled tubes |
EP0252356A1 (en) * | 1986-06-25 | 1988-01-13 | Naphtachimie S.A. | Process and furnace for the steam cracking of hydrocarbons for the preparation of olefins and diolefins |
EP0252355A1 (en) * | 1986-06-25 | 1988-01-13 | Naphtachimie S.A. | Process and furnace for the steam cracking of hydrocarbons for the preparation of olefins and diolefins |
EP0305799A1 (en) * | 1987-09-01 | 1989-03-08 | Abb Lummus Crest Inc. | Pyrolysis heater |
-
1992
- 1992-05-22 EP EP92108658A patent/EP0519230A1/en not_active Withdrawn
- 1992-06-16 JP JP4180547A patent/JPH0613710B2/en not_active Expired - Lifetime
- 1992-06-16 KR KR1019920010397A patent/KR950005680B1/en active IP Right Grant
- 1992-06-17 CN CN92104888A patent/CN1026120C/en not_active Expired - Fee Related
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3274978A (en) * | 1964-02-24 | 1966-09-27 | Lummus Co | Vertical tube fluid heater |
GB1194733A (en) * | 1966-08-26 | 1970-06-10 | Pullman Inc | Furnace for Heating Reactant Fluids |
US3630850A (en) * | 1968-12-02 | 1971-12-28 | Shell Oil Co | Cracking furnace with burners engaging mirror image coiled tubes |
EP0252356A1 (en) * | 1986-06-25 | 1988-01-13 | Naphtachimie S.A. | Process and furnace for the steam cracking of hydrocarbons for the preparation of olefins and diolefins |
EP0252355A1 (en) * | 1986-06-25 | 1988-01-13 | Naphtachimie S.A. | Process and furnace for the steam cracking of hydrocarbons for the preparation of olefins and diolefins |
EP0305799A1 (en) * | 1987-09-01 | 1989-03-08 | Abb Lummus Crest Inc. | Pyrolysis heater |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2760467A1 (en) * | 1997-03-04 | 1998-09-11 | Procedes Petroliers Petrochim | Steam cracking furnace, used to make ethylene or propylene |
FR2761371A1 (en) * | 1997-03-28 | 1998-10-02 | Procedes Petroliers Petrochim | Tubular furnace for cracking hydrocarbon(s) in the presence of steam |
EP1417098A1 (en) * | 2001-04-24 | 2004-05-12 | ABB Lummus Global Inc. | Pyrolysis heater |
EP1417098A4 (en) * | 2001-04-24 | 2006-11-29 | Abb Lummus Global Inc | Pyrolysis heater |
WO2002100982A1 (en) * | 2001-06-13 | 2002-12-19 | Abb Lummus Global Inc. | Pyrolysis heater with paired burner zoned firing system |
EP1295930A1 (en) * | 2001-09-19 | 2003-03-26 | China Petroleum & Chemical Corporation | Pyrolysis furnace with new type radiant tubes arrangement and method of its operation and usage |
WO2003087268A2 (en) * | 2002-04-10 | 2003-10-23 | Abb Lummus Global Inc. | Cracking furnace with more uniform heating |
WO2003087268A3 (en) * | 2002-04-10 | 2003-11-20 | Abb Lummus Global Inc | Cracking furnace with more uniform heating |
US7004085B2 (en) | 2002-04-10 | 2006-02-28 | Abb Lummus Global Inc. | Cracking furnace with more uniform heating |
US8490581B2 (en) | 2006-06-15 | 2013-07-23 | Exxonmobil Research And Engineering Company | Advanced fired heater unit for use in refinery and petro-chemical applications |
EP2949728A1 (en) | 2014-05-28 | 2015-12-02 | Wison Engineering Ltd. | Ethylene cracking furnace |
Also Published As
Publication number | Publication date |
---|---|
JPH05186779A (en) | 1993-07-27 |
JPH0613710B2 (en) | 1994-02-23 |
KR950005680B1 (en) | 1995-05-29 |
CN1067669A (en) | 1993-01-06 |
CN1026120C (en) | 1994-10-05 |
KR930000654A (en) | 1993-01-15 |
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Legal Events
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PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
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AK | Designated contracting states |
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Effective date: 19941124 |
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Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
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18D | Application deemed to be withdrawn |
Effective date: 19950405 |