US3204611A - Firebox heat pattern in a furnace - Google Patents

Firebox heat pattern in a furnace Download PDF

Info

Publication number
US3204611A
US3204611A US283752A US28375263A US3204611A US 3204611 A US3204611 A US 3204611A US 283752 A US283752 A US 283752A US 28375263 A US28375263 A US 28375263A US 3204611 A US3204611 A US 3204611A
Authority
US
United States
Prior art keywords
firebox
furnace
housing
oil
temperature
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.)
Expired - Lifetime
Application number
US283752A
Inventor
Bruce E Stone
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Phillips Petroleum Co
Original Assignee
Phillips Petroleum Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Phillips Petroleum Co filed Critical Phillips Petroleum Co
Priority to US283752A priority Critical patent/US3204611A/en
Application granted granted Critical
Publication of US3204611A publication Critical patent/US3204611A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C1/00—Combustion apparatus specially adapted for combustion of two or more kinds of fuel simultaneously or alternately, at least one kind of fuel being either a fluid fuel or a solid fuel suspended in a carrier gas or air
    • F23C1/08—Combustion apparatus specially adapted for combustion of two or more kinds of fuel simultaneously or alternately, at least one kind of fuel being either a fluid fuel or a solid fuel suspended in a carrier gas or air liquid and gaseous fuel
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C5/00—Disposition of burners with respect to the combustion chamber or to one another; Mounting of burners in combustion apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C2900/00—Special features of, or arrangements for combustion apparatus using fluid fuels or solid fuels suspended in air; Combustion processes therefor
    • F23C2900/05081—Disposition of burners relative to each other creating specific heat patterns

Definitions

  • the invention relates to a method and means for improving the heat pattern or temperature profile in a furnace.
  • the invention relates to improving the temperature profile in a combination convection-radiant furnace for heating a bank of heat exchange tubes.
  • Furnaces which utilize both convection and radiant heating for heating and cracking of hydrocarbons to more valuable products are used extensively in the oil industry as well as in other heating applications. Oil is conventionally heated in such furnaces for further processing such as thermal and catalytic cracking, vacuum reducing of topped crude oil and other processes.
  • topped crude oil In the vacuum reduction or vacuum flashing of topped crude oil to produce heavy gas oils for feed to a catalytic cracking process and a residuum of asphalt, it is desirable to heat the topped crude charge to a temperature just below the cracking temperature of the charge and to pass the heated charge into the vacuum distillation apparatus in as short a time as practical and at as low a pressure as practical.
  • the topped crude oil charge is usually heated in a tube furnace wherein the heat exchange tubes define a serpentine path through the furnace. Steam is often admitted to the oil charge passing through the furnace to suppress cracking of the oil in the furnace tubes.
  • the present invention is applicable to a box-type tube furnace which is end fired with oil burners and is side fired with radiant-type gas burners.
  • the oil is preheated in the top section of the furnace above the firebox and is then heated in banks of tubes horizontally positioned along the walls of the furnace surrounding the firebox section of the furnace.
  • the furnace is rectangular in shape with the sides being substantially longer than the ends.
  • the firebox temperature profile can be improved substantially by injecting steam into the sides of the firebox adjacent the fiame issuing from the end oil burners and perpendicular to the flame emanating from the oil burners.
  • the injection of steam into the end portions of the firebox as described not only lowers the firebox temperature at the center portion of the firebox but raises the firebox temperature at the end portions of the firebox thereby tending to level out the temperature profile across the longitudinal dimension of the firebox.
  • steam injection according to the invention permits an increase in the amount of oil fuel charged to the end oil burners without raising the temperature of the firebox at the center portion above the maximum desired temperature and also makes possible the processing of an increased amount of topped crude charge.
  • the side gas burners are of the screen type.
  • a typical burner is a Selas Corporation Refrak screen burner as described in Bulletin ZOS-C of the Selas Corporation of America, Philadelphia, Pennsylvania.
  • the end oil burners are conventional oil burners.
  • a typical burner is a John Zink Company series CBM combination gas and oil burner which is oil fired, as described in Bulletin CBM-l of John Zink Company, Tulsa, Oklahoma.
  • the steam nozzle at the end of the steam injection conduit can be the open end of the steam conduit or any type of restriction if the steam conduit is of such size as requires restriction.
  • the amount of steam will usually be from 2500 to 10,000 pounds per hour (lb./hr.).
  • FIGURE 1 is a perspective view, partly in section, of a furnace according to the invention.
  • FIGURE 2 is a horizontal cross section in plan view of the firebox of the furnace of FIGURE 11;
  • FIGURE 3 is a graphic illustration of the temperature profile of the furnace.
  • a furnace It has insulated walls 11 enclosing a firebox section 12 and 'a convection heating section 13 wherein heat exchange tubes 14 are heated by combustion of fuel in side gas burners 15 and end oil burners 16. Flue gases are removed by means of stack 17. Steam is admitted into the firebox 12 via conduits 18 and nozzles 19.
  • FIGURE 2 The relationship of the steam nozzles to the end burners is shown in FIGURE 2. Oil is supplied to the end burners by a manifold 21 and gas is supplied to the side burners by manifold 22.
  • the steam conduits I8 terminate in a nozzle 19.
  • the floor 20 of the furnace is insulated with insulation similar to that employed for insulating the walls Jill.
  • a center bridge wall 23 is positioned in the firebox section 12 between the opposite rows of gas burners 15.
  • the firebox temperature was determined by thermocouples positioned in the center and end portions of the furnace and these temperatures are shown graphically in FIGURE 3. It should be noted that steam injection benefitted the temperature profile of the furnace firebox to the extent that the topped crude charged to the furnace could be increased by 1,800 barrels per day even though the temperature of the oil charged to the furnace was considerably lower than in the run where steam is not used.
  • a tube furnace comprising a housing; a firebox in said housing; a bank of heat-exchange tubes supported adjacent the housing Walls; outlet means from said housing; an oil burner positioned in each end of said housing and projecting into said firebox; a gas burner positioned in each side of said housing about the center thereof and projecting into said firebox; and steam injection means positioned in each side of and adjacent the end of the housing for injecting steam into the firebox at a point into admixture with the oil emanating from the oil burner and at substantially a right angle to the flame emanating from the oil burner in an amount sufiicient to increase the temperature of the end portions of the firebox and to reduce the temperature of the center portion of the firebox.
  • a tube furnace comprising a housing; a firebox in n to it said housing; a bank of heat-exchange tubes supported adjacent the housing walls; outlet means from said housing; an oil burner positioned in each end of said housing and projecting into said firebox; a gas burner positioned in each side of said housing about the center thereof and projecting into said firebox; and steam injection means positioned in each side of and adjacent the end of the housing for injecting steam into the firebox at a point into admixture With the oil emanating from the oil burner and at substantially a right angle to the flame emanating from the oil burner in an amount sufficient to increase the temperature of the end portions of the firebox and reduce the temperature of the center portion of the firebox to permit an increase in the amount of oil fuel charged to the oil burner.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Combustion Of Fluid Fuel (AREA)

Description

S@pt. 7, 1965 B. E. STONE 3,204,611
FIREBOX HEAT PATTERN IN A FURNACE Filed May 28, 1963 2 Sheets-Sheet 1 INVENTOR.
B. E. STON E A TTORNEKS m- 7, 1965 B. E. STONE 3,204,611
FIREBOX HEAT PATTERN IN A FURNACE Filed May 28, 1963 2 Sheets-Sheet 2 F TEAM 8 O|L j AIR GAS
FIG. 2
A 00 I600 c (I 2 I400 5 I300 11 A 2 1200 L2 A woo woo
FIRST END CENTER SECOND END OF FURNACE OF FURNACE OF FURNACE FIG. 3
INVENTOR. B. ESTONE A 7 TORNE Y5 United States Patent 3,204,611 FIREEU X HEAT PATTERN TN A FURNACE Bruce E. Stone, Kansas City, Kane, assignor to Phillips Petroleum Company, a corporation of Delaware Filed May 28, I963, Ser. No. 283,752 3 Claims. (Cl. 122-236) The invention relates to a method and means for improving the heat pattern or temperature profile in a furnace. In one aspect the invention relates to improving the temperature profile in a combination convection-radiant furnace for heating a bank of heat exchange tubes.
Furnaces which utilize both convection and radiant heating for heating and cracking of hydrocarbons to more valuable products are used extensively in the oil industry as well as in other heating applications. Oil is conventionally heated in such furnaces for further processing such as thermal and catalytic cracking, vacuum reducing of topped crude oil and other processes.
In the vacuum reduction or vacuum flashing of topped crude oil to produce heavy gas oils for feed to a catalytic cracking process and a residuum of asphalt, it is desirable to heat the topped crude charge to a temperature just below the cracking temperature of the charge and to pass the heated charge into the vacuum distillation apparatus in as short a time as practical and at as low a pressure as practical. The topped crude oil charge is usually heated in a tube furnace wherein the heat exchange tubes define a serpentine path through the furnace. Steam is often admitted to the oil charge passing through the furnace to suppress cracking of the oil in the furnace tubes.
The present invention is applicable to a box-type tube furnace which is end fired with oil burners and is side fired with radiant-type gas burners. The oil is preheated in the top section of the furnace above the firebox and is then heated in banks of tubes horizontally positioned along the walls of the furnace surrounding the firebox section of the furnace. The furnace is rectangular in shape with the sides being substantially longer than the ends.
I have discovered that the firebox temperature profile can be improved substantially by injecting steam into the sides of the firebox adjacent the fiame issuing from the end oil burners and perpendicular to the flame emanating from the oil burners. I have found that the injection of steam into the end portions of the firebox as described not only lowers the firebox temperature at the center portion of the firebox but raises the firebox temperature at the end portions of the firebox thereby tending to level out the temperature profile across the longitudinal dimension of the firebox. I have further found that steam injection according to the invention permits an increase in the amount of oil fuel charged to the end oil burners without raising the temperature of the firebox at the center portion above the maximum desired temperature and also makes possible the processing of an increased amount of topped crude charge.
The side gas burners are of the screen type. A typical burner is a Selas Corporation Refrak screen burner as described in Bulletin ZOS-C of the Selas Corporation of America, Philadelphia, Pennsylvania.
The end oil burners are conventional oil burners. A typical burner is a John Zink Company series CBM combination gas and oil burner which is oil fired, as described in Bulletin CBM-l of John Zink Company, Tulsa, Oklahoma.
The steam nozzle at the end of the steam injection conduit can be the open end of the steam conduit or any type of restriction if the steam conduit is of such size as requires restriction. The amount of steam will usually be from 2500 to 10,000 pounds per hour (lb./hr.).
It is an object of this invention to provide a method and means for improving the temperature profile in the firebox of a furnace. It is also an object of this invention to improve the heating properties of a furnace fired by a combination of oil burners and gas burners. Still another object of the invention is to provide a furnace having improved heating properties for heating the topped crude charge to a vacuum flasher. Other objects and advantages will be apparent to one skilled in the art upon study of this disclosure including the detailed description of the invention and the appended drawing wherein:
FIGURE 1 is a perspective view, partly in section, of a furnace according to the invention;
FIGURE 2 is a horizontal cross section in plan view of the firebox of the furnace of FIGURE 11; and
FIGURE 3 is a graphic illustration of the temperature profile of the furnace.
Referring now to FIGURE 1, a furnace It) has insulated walls 11 enclosing a firebox section 12 and 'a convection heating section 13 wherein heat exchange tubes 14 are heated by combustion of fuel in side gas burners 15 and end oil burners 16. Flue gases are removed by means of stack 17. Steam is admitted into the firebox 12 via conduits 18 and nozzles 19.
The relationship of the steam nozzles to the end burners is shown in FIGURE 2. Oil is supplied to the end burners by a manifold 21 and gas is supplied to the side burners by manifold 22. The steam conduits I8 terminate in a nozzle 19. The floor 20 of the furnace is insulated with insulation similar to that employed for insulating the walls Jill. A center bridge wall 23 is positioned in the firebox section 12 between the opposite rows of gas burners 15.
The following example will be helpful in attaining an understanding of the invention but should not be considered as unduly limiting the invention.
EXAMPLE Table Run 1 Run 2 Feed to furnace, bb]./hr 480 555 Feed temperature, F 227 156 Furnace outlet temperature, 820 832 Furnace stack temperature, F 925 920 Steam to firebox, lb./hr 0 5, 000 Firebox temperature (1st; end), F. 1,240 1, 500 Firebox temperature (center), F 1, 660 1, 610 Firebox temperature (2nd end), F 1, 160 1, 475
The firebox temperature was determined by thermocouples positioned in the center and end portions of the furnace and these temperatures are shown graphically in FIGURE 3. It should be noted that steam injection benefitted the temperature profile of the furnace firebox to the extent that the topped crude charged to the furnace could be increased by 1,800 barrels per day even though the temperature of the oil charged to the furnace was considerably lower than in the run where steam is not used.
That which is claimed is:
1. The method of improving the temperature pattern in a tube furnace having a housing, a firebox in said housing, a bank of heat-exchange tubes supported adjacent the housing Walls, outlet means from said housing, an oil burner positioned in each end of said housing and projecting into said firebox, a gas burner positioned in each side of said housing about the center thereof and projecting into said firebox, comprising injecting an amount of steam sufficient to increase the temperature of the end portions of the firebox and reduce the temperature of the center portion of the firebox, into the end portions of the firebox substantially at a right angle to the flame emanating from the oil burner and into admixture with the oil emanating from the oil burner.
2. A tube furnace comprising a housing; a firebox in said housing; a bank of heat-exchange tubes supported adjacent the housing Walls; outlet means from said housing; an oil burner positioned in each end of said housing and projecting into said firebox; a gas burner positioned in each side of said housing about the center thereof and projecting into said firebox; and steam injection means positioned in each side of and adjacent the end of the housing for injecting steam into the firebox at a point into admixture with the oil emanating from the oil burner and at substantially a right angle to the flame emanating from the oil burner in an amount sufiicient to increase the temperature of the end portions of the firebox and to reduce the temperature of the center portion of the firebox.
3. A tube furnace comprising a housing; a firebox in n to it said housing; a bank of heat-exchange tubes supported adjacent the housing walls; outlet means from said housing; an oil burner positioned in each end of said housing and projecting into said firebox; a gas burner positioned in each side of said housing about the center thereof and projecting into said firebox; and steam injection means positioned in each side of and adjacent the end of the housing for injecting steam into the firebox at a point into admixture With the oil emanating from the oil burner and at substantially a right angle to the flame emanating from the oil burner in an amount sufficient to increase the temperature of the end portions of the firebox and reduce the temperature of the center portion of the firebox to permit an increase in the amount of oil fuel charged to the oil burner.
References tilited hy the Examiner UNITED STATES PATENTS 2,077,676 4/37 Darling 15874 2,102,876 12/37 Barnes 122-356 2,184,465 12/39 Ocon 122356 2,294,977 9/42 Garrison et al. 122356 PERCY L. PATRICK, Primaiy Examiner.
RENIJETE'I W. SERAGUE, ROBERT A. OLEARY,
Examiners.

Claims (1)

1. THE METHOD OF IMPROVING THE TEMPERATURE PATTERN IN A TUBE FURNACE HAVING A HOUSNG, A FIREBOX IN SAID HOUSING, A BANK OF HEAT-EXCHANGE TUBES SUPPORTED ADJACENT THE HOUSING WALLS, OUTLET MEANS FROM SAID HOUSING, AN OIL BURNER POSITIONED IN EACH END OF SAID HOUSING AND PROJECTING INTO SAID FIREBOX, A GAS BURNER POSITIONED IN EACH SIDE OF SAID HOUSING ABOUT THE CENTER THEREOF AND PROJECTING INTO SAID FIREBOX, COMPRISING INJECTING AN AMOUNT OF STEM SUFFICIENT TO INCREASE THE TEMPERATURE OF THE END PORTIONS OF THE FIREBOX AND REDUCE THE TEMPERATURE OF THE CENTER PORTION OF THE FIREBOX, INTO THE END PORTION OF THE FIREBOX SUBSTANTIALLY AT A RIGHT ANGLE TO THE FLAME EMANATING FROM THE OIL BURNER AND INTO ADMIXTURE WITH THE OILE EMANATING FROM THE OILE BURNER.
US283752A 1963-05-28 1963-05-28 Firebox heat pattern in a furnace Expired - Lifetime US3204611A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US283752A US3204611A (en) 1963-05-28 1963-05-28 Firebox heat pattern in a furnace

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US283752A US3204611A (en) 1963-05-28 1963-05-28 Firebox heat pattern in a furnace

Publications (1)

Publication Number Publication Date
US3204611A true US3204611A (en) 1965-09-07

Family

ID=23087404

Family Applications (1)

Application Number Title Priority Date Filing Date
US283752A Expired - Lifetime US3204611A (en) 1963-05-28 1963-05-28 Firebox heat pattern in a furnace

Country Status (1)

Country Link
US (1) US3204611A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL7601811A (en) * 1975-05-30 1976-12-02 Kraftwerk Union Ag BURNER SET-UP FOR A STEAM GENERATOR WITH A BURNER FOR POWDER COAL AND GAS.
EP0661497A2 (en) * 1993-12-28 1995-07-05 Chiyoda Corporation Pipestill heater and method for controlling combustion in pipestill heater
WO2008074780A1 (en) * 2006-12-20 2008-06-26 L'air Liquide Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Melting process using the combustion of liquid and gaseous fuels
US20160076761A1 (en) * 2014-09-17 2016-03-17 Atd Combustors, Llc Furnaces and methods of reducing heat degrading of metal heating coils of furnaces

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2077676A (en) * 1933-06-14 1937-04-20 Diversified Patents Inc Firebox construction
US2102876A (en) * 1933-10-30 1937-12-21 Universal Oil Prod Co Heating of fluids
US2184465A (en) * 1938-08-08 1939-12-26 Cecilio L Ocon Furnace for heat treating carbonaceous material
US2294977A (en) * 1940-07-02 1942-09-08 James N Garrison Heater

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2077676A (en) * 1933-06-14 1937-04-20 Diversified Patents Inc Firebox construction
US2102876A (en) * 1933-10-30 1937-12-21 Universal Oil Prod Co Heating of fluids
US2184465A (en) * 1938-08-08 1939-12-26 Cecilio L Ocon Furnace for heat treating carbonaceous material
US2294977A (en) * 1940-07-02 1942-09-08 James N Garrison Heater

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL7601811A (en) * 1975-05-30 1976-12-02 Kraftwerk Union Ag BURNER SET-UP FOR A STEAM GENERATOR WITH A BURNER FOR POWDER COAL AND GAS.
EP0661497A2 (en) * 1993-12-28 1995-07-05 Chiyoda Corporation Pipestill heater and method for controlling combustion in pipestill heater
EP0661497A3 (en) * 1993-12-28 1996-04-24 Chiyoda Chem Eng Construct Co Pipestill heater and method for controlling combustion in pipestill heater.
WO2008074780A1 (en) * 2006-12-20 2008-06-26 L'air Liquide Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Melting process using the combustion of liquid and gaseous fuels
FR2910594A1 (en) * 2006-12-20 2008-06-27 Air Liquide FUSION PROCESS USING COMBUSTION OF LIQUID AND GASEOUS FUELS
US20160076761A1 (en) * 2014-09-17 2016-03-17 Atd Combustors, Llc Furnaces and methods of reducing heat degrading of metal heating coils of furnaces
US9989246B2 (en) * 2014-09-17 2018-06-05 Atd Combustors, Llc Furnaces and methods of reducing heat degrading of metal heating coils of furnaces

Similar Documents

Publication Publication Date Title
US2218281A (en) Method for cooling flue gas
SU1621812A3 (en) Method of producing ethylene
US3204611A (en) Firebox heat pattern in a furnace
US2253920A (en) Radiant tube heater
US2081970A (en) Apparatus and process for heating fluids
US2361812A (en) Heating of fluids
GB855764A (en) Process of and regenerative furnace for the pyrolysis of an in-gas containing a desired hydrocarbon
GB1022804A (en) Improvements in or relating to the production of oil gas
US2114269A (en) Heating apparatus and method
DE1284027B (en) Furnace for the production of fuel gases
US2029293A (en) Heating of fluids
US2598840A (en) Heater for hydrocarbon fluid
US2172105A (en) Method of firing furnaces
US2129900A (en) Heating of fluids
US2112224A (en) Radiant heat furnace
US3221711A (en) Ridge firing arrangement for process heaters
US2081927A (en) Heating process and apparatus
US2034362A (en) Pipe heater construction
US2415726A (en) Apparatus for heating oils
US2146497A (en) Heating of fluids
US2219860A (en) Heating apparatus
US2246469A (en) Heating of fluids
US2224917A (en) Method of heating fluids
US2396200A (en) Fluid heater
US2043095A (en) Method of and apparatus for heating fluids