US2907288A - Furnaces - Google Patents
Furnaces Download PDFInfo
- Publication number
- US2907288A US2907288A US379789A US37978953A US2907288A US 2907288 A US2907288 A US 2907288A US 379789 A US379789 A US 379789A US 37978953 A US37978953 A US 37978953A US 2907288 A US2907288 A US 2907288A
- Authority
- US
- United States
- Prior art keywords
- combustion
- combustion chamber
- air
- furnace
- furnaces
- 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
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
- F23C99/00—Subject-matter not provided for in other groups of this subclass
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B21/00—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B21/00—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically
- F22B21/34—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically built-up from water tubes grouped in panel form surrounding the combustion chamber, i.e. radiation boilers
- F22B21/341—Vertical radiation boilers with combustion in the lower part
- F22B21/343—Vertical radiation boilers with combustion in the lower part the vertical radiation combustion chamber being connected at its upper part to a sidewards convection chamber
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23B—METHODS OR APPARATUS FOR COMBUSTION USING ONLY SOLID FUEL
- F23B5/00—Combustion apparatus with arrangements for burning uncombusted material from primary combustion
- F23B5/02—Combustion apparatus with arrangements for burning uncombusted material from primary combustion in main combustion chamber
-
- 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
- F23C2700/00—Special arrangements for combustion apparatus using fluent fuel
- F23C2700/06—Combustion apparatus using pulverized fuel
- F23C2700/063—Arrangements for igniting, flame-guiding, air supply in
Definitions
- This invention relates to a furnace for the combustion of powdered or small-size solid fuel and also for liquid or gaseous fuels alone or in combination with solid fuels.
- the furnace according to the invention comprises a longitudinally extended combustion chamber having a plurality of means for the supply of crushed or finely divided fuel and combustion air, said means being arranged to impart to the fuel and combus tion air a substantially helical movement around an imaginary axis, the main axis of the combustion chamber, and a gas outlet opening the cross sectional area of which is considerably smaller than the cross sectional area of the combustion chamber which downwardly merges into a trough-shaped shaft.
- an auxiliary furnace having a grate for separate combustion is provided below the trough-shaped shaft and in open communication therewith.
- This grate may be a longitudinally extended moving grate or a circular grate.
- it may be suitable to provide a plurality of minor grates.
- the arrangement according to the invention permits of controlling the course of combustion by external means so as to vary the posi tion of the combustion zone in a vertical direction in spite of the thermal gas flow, this possibility being important with regard to varying properties of the fuel.
- it is highly desirable to have the possibility of controlling the fiue gas temperature at the outlet of the combustion chamber such as to maintain constant the steam temperature at varying rates of steam generation.
- the control of the course of combustion by external means is efiected by a certain location and shape of the air inlet openings.
- some of the air inlet openings are located in the upper portion of the combustion chamber and other openings are located in the lower portion, at least part of these openings being directed tangentially to the combustion chamber.
- the supply conduits for the upper and lowerair inlet openings may-be combined with each other and provided-with an air distributing device to vary the proportion between 'thetwo'main air streams supplied to the combustion chamber.
- the furnace may communicate with a reheater into which a small amount of combustion air may be supplied in a suitable manner, or directly with heat absorption surfaces.
- Figure 1 is a vertical sectional view of the invention.
- Figure 2 is a transverse sectional view of the form shown in Figure 1.
- numeral 1 denotes the wall of a combustion chamber which is entirely or partly covered on the inside with tubes 2 for a fluid, such as circulating water, for generating steam or hot water.
- the tubes may communicate with a steam dome 3-provided above the combustion chamber.
- the furnace 1 has a circular or annular grate 32, resulting in a more symmetrical arrangement of the entire furnace.
- Primary combustion air is supplied in the usual manner from below through the above described grates of the furnace which acts to stabilize the combustion in the combustion chamber.
- the constricted outlet opening 19 communicates with a reheater 34 in which complete combustion may be carried out.
- tangentially directed air supply conduits 35 communicate with the reheater immediately above the outlet opening of the combustion chamber.
- the air supply conduit 35 is connected to a supply system for the upper and lower part of the combustion chamber.
- the distributor 26 By means of the distributor 26, the air is divided into two main streams the upper one of which is partly admitted into the reheater 34.
- flap valves 36 and 37 the proportion between the air quantities entering through the conduits 24 and 35 may be varied in accordance with requirements. Alternatively, air may be separately supplied to the reheater 34.
- outlets 19 and the constricting members may be constructed as a supplementary structure including water-cooled boiler tubes, and openings may be provided.
- a furnace for steam boilers and the like comprising an elongated combustion chamber for burning finely divided fuel and intended to operate at so low temperatures that the mineral constituents in the ash will substantially not melt, a radiant chamber above said combustion chamber, said combustion chamber having at its upper end a gas outlet opening communicating with said radiant chamber and located substantially centrally thereof, boiler fluid tubes positioned adjacent the walls of said combustion chamber, a steam drum above said radiant chamber and communicating with said tubes, means for supplying finely divided fuel into said combustion chamber, a plurality of means located at different planes transverse to the longitudinal axis of said combustion chamber for introducing combustion air into said combustion chamber, said fuel and combustion air being introduced tangentially into the combustion chamber so as to impart to the fuel and combustion air a substantially helical movement around said longitudinal axis, said gas outlet opening having a depending rim extending into said combustion chamber, said furnace hav- 3 ing a tubular distributor provided with an upper branch and a'lower branch for introducing combustion airta'ngentially into the combustion chamber, one of said branches
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Solid-Fuel Combustion (AREA)
Description
Oct. 6, 1959 U. o; BL5M m 2,907,288
FURNACES Filed Sept. 14. 1953.
United States Patent FURNACES Uno Olof Blomquist, Vasteras, Sweden, assignor to AB SvenskaMaskinverken, Sodertalje, Sweden, a corpora- 7 This invention relates to a furnace for the combustion of powdered or small-size solid fuel and also for liquid or gaseous fuels alone or in combination with solid fuels.
In modern longitudinaly extended furnaces of common type for steam boilers or the like, the mode and rate of combustion are substantially dependent upon the differences in temperature occurring in the furnace and the thermal gas flow caused by said temperature differences. Accordingly, combustion will substantially take place in the central portion of the furnace, while the surrounding portion is poorly utilized, resulting in a low average rate of combustion. In order to increase the rate of combustion, it has become common practice to induce a revolving motion tothe mass of gases, for instance by the use of tangentially directed burners placed in the corners of the furnace, the result being, however, not very satisfactory. In addition, it is difficult in steam boilers of usual construction to maintain constant the temperature of superheat of the steam at greatly varying steam generation. Further, it is not possible to vary to a noticeable degree the conditions of combustion with regard to the properties of different fuels.
It is the object of this invention to eliminate the above inconveniencies. The furnace according to the invention comprises a longitudinally extended combustion chamber having a plurality of means for the supply of crushed or finely divided fuel and combustion air, said means being arranged to impart to the fuel and combus tion air a substantially helical movement around an imaginary axis, the main axis of the combustion chamber, and a gas outlet opening the cross sectional area of which is considerably smaller than the cross sectional area of the combustion chamber which downwardly merges into a trough-shaped shaft. In a preferred embodiment of the invention, an auxiliary furnace having a grate for separate combustion is provided below the trough-shaped shaft and in open communication therewith. This grate may be a longitudinally extended moving grate or a circular grate. In large furnaces and particularly in vertical furnaces, it may be suitable to provide a plurality of minor grates. Especially in furnaces having a vertical main axis the arrangement according to the invention permits of controlling the course of combustion by external means so as to vary the posi tion of the combustion zone in a vertical direction in spite of the thermal gas flow, this possibility being important with regard to varying properties of the fuel. In connection with steam boilers it is highly desirable to have the possibility of controlling the fiue gas temperature at the outlet of the combustion chamber such as to maintain constant the steam temperature at varying rates of steam generation.
The control of the course of combustion by external means is efiected by a certain location and shape of the air inlet openings. Preferably some of the air inlet openings are located in the upper portion of the combustion chamber and other openings are located in the lower portion, at least part of these openings being directed tangentially to the combustion chamber. Between the upper and lower air inlet openings and/or at the same level as these openings, there are provided means for the supply of fuel. The supply conduits for the upper and lowerair inlet openings may-be combined with each other and provided-with an air distributing device to vary the proportion between 'thetwo'main air streams supplied to the combustion chamber. The furnace may communicate with a reheater into which a small amount of combustion air may be supplied in a suitable manner, or directly with heat absorption surfaces.
Referring to the drawings:
Figure 1 is a vertical sectional view of the invention.
Figure 2 is a transverse sectional view of the form shown in Figure 1.
Referring to the drawing, numeral 1 denotes the wall of a combustion chamber which is entirely or partly covered on the inside with tubes 2 for a fluid, such as circulating water, for generating steam or hot water. The tubes may communicate with a steam dome 3-provided above the combustion chamber.
According to Figs. 1 and 2, the furnace 1 has a circular or annular grate 32, resulting in a more symmetrical arrangement of the entire furnace.
Primary combustion air is supplied in the usual manner from below through the above described grates of the furnace which acts to stabilize the combustion in the combustion chamber.
The constricted outlet opening 19 according to Figs. 1 and 2 communicates with a reheater 34 in which complete combustion may be carried out. To this end, tangentially directed air supply conduits 35 communicate with the reheater immediately above the outlet opening of the combustion chamber. The air supply conduit 35 is connected to a supply system for the upper and lower part of the combustion chamber. By means of the distributor 26, the air is divided into two main streams the upper one of which is partly admitted into the reheater 34. By means of flap valves 36 and 37, the proportion between the air quantities entering through the conduits 24 and 35 may be varied in accordance with requirements. Alternatively, air may be separately supplied to the reheater 34.
The invention may be used to improve existing radiation type furnaces. To this end, the outlets 19 and the constricting members may be constructed as a supplementary structure including water-cooled boiler tubes, and openings may be provided.
What I claim is: v
A furnace for steam boilers and the like comprising an elongated combustion chamber for burning finely divided fuel and intended to operate at so low temperatures that the mineral constituents in the ash will substantially not melt, a radiant chamber above said combustion chamber, said combustion chamber having at its upper end a gas outlet opening communicating with said radiant chamber and located substantially centrally thereof, boiler fluid tubes positioned adjacent the walls of said combustion chamber, a steam drum above said radiant chamber and communicating with said tubes, means for supplying finely divided fuel into said combustion chamber, a plurality of means located at different planes transverse to the longitudinal axis of said combustion chamber for introducing combustion air into said combustion chamber, said fuel and combustion air being introduced tangentially into the combustion chamber so as to impart to the fuel and combustion air a substantially helical movement around said longitudinal axis, said gas outlet opening having a depending rim extending into said combustion chamber, said furnace hav- 3 ing a tubular distributor provided with an upper branch and a'lower branch for introducing combustion airta'ngentially into the combustion chamber, one of said branches communicating with said radiant chamber above said gas outlet. 5
:ReferencesCitedin thcfile of this patent UNITED STATES PATENTS 901,232 Eldred- 'Oct. 13, 1908 1,091,475 Best Mar. '31, 1914 10 1,918,397 Jezler July 18, 1933 '4 1 Kerr et a1. Sept. 5, 1944 Lemaire Aug. 16, 1949 Glaeser Oct. 4, 1949 Kreisinger Nov. 6, 1951 Birkner Jan. 17, 1956 Hubel May 28, 1957 FOREIGN PATENTS Great Britain Mar. 22, 1923 Great Britain Dec. :11, 1928
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE2907288X | 1952-09-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2907288A true US2907288A (en) | 1959-10-06 |
Family
ID=20427761
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US379789A Expired - Lifetime US2907288A (en) | 1952-09-20 | 1953-09-14 | Furnaces |
Country Status (1)
Country | Link |
---|---|
US (1) | US2907288A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3356075A (en) * | 1965-10-12 | 1967-12-05 | Combustion Eng | Method of pulverized coal firing a steam generator and controlling steam temperature |
US4002127A (en) * | 1975-03-13 | 1977-01-11 | Derek Angus | Cyclone structure |
US6269755B1 (en) | 1998-08-03 | 2001-08-07 | Independent Stave Company, Inc. | Burners with high turndown ratio |
RU2648314C2 (en) * | 2015-12-24 | 2018-03-23 | Евгений Михайлович Пузырёв | Boiler with chamber furnace |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US901232A (en) * | 1908-05-07 | 1908-10-13 | Byron E Eldred | Process of producing gas. |
US1091475A (en) * | 1904-02-19 | 1914-03-31 | John H Best | Tangential-flame furnace. |
GB194861A (en) * | 1922-10-23 | 1923-03-22 | Roy Norman Buell | Improvements in or relating to furnaces for burning of pulverised fuel |
US1573910A (en) * | 1924-12-11 | 1926-02-23 | Morris Klivansky | Attachment for motor vehicles |
GB302255A (en) * | 1927-08-11 | 1928-12-11 | Arthur Musker | Improvements in and relating to the use of pulverized coal or liquid fuel as fuel for steam generators and the like |
US1918397A (en) * | 1930-03-05 | 1933-07-18 | Jezler Hubert | Firing of steam boilers |
US2357302A (en) * | 1941-03-07 | 1944-09-05 | Babcock & Wilcox Co | Method of and apparatus for burning fuel |
US2479376A (en) * | 1941-04-06 | 1949-08-16 | Mure Combustibles Et Ind Sa | Furnace plant for consuming raw coal dust |
US2483728A (en) * | 1945-09-18 | 1949-10-04 | Hercules Powder Co Ltd | Method and apparatus for burning high moisture content fuel |
US2730998A (en) * | 1949-07-11 | 1956-01-17 | Birkner Max | Apparatus for burning solid fuel |
US2793626A (en) * | 1952-06-18 | 1957-05-28 | Babcock & Wilcox Co | Fuel burning apparatus |
-
1953
- 1953-09-14 US US379789A patent/US2907288A/en not_active Expired - Lifetime
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1091475A (en) * | 1904-02-19 | 1914-03-31 | John H Best | Tangential-flame furnace. |
US901232A (en) * | 1908-05-07 | 1908-10-13 | Byron E Eldred | Process of producing gas. |
GB194861A (en) * | 1922-10-23 | 1923-03-22 | Roy Norman Buell | Improvements in or relating to furnaces for burning of pulverised fuel |
US1573910A (en) * | 1924-12-11 | 1926-02-23 | Morris Klivansky | Attachment for motor vehicles |
GB302255A (en) * | 1927-08-11 | 1928-12-11 | Arthur Musker | Improvements in and relating to the use of pulverized coal or liquid fuel as fuel for steam generators and the like |
US1918397A (en) * | 1930-03-05 | 1933-07-18 | Jezler Hubert | Firing of steam boilers |
US2357302A (en) * | 1941-03-07 | 1944-09-05 | Babcock & Wilcox Co | Method of and apparatus for burning fuel |
US2479376A (en) * | 1941-04-06 | 1949-08-16 | Mure Combustibles Et Ind Sa | Furnace plant for consuming raw coal dust |
US2483728A (en) * | 1945-09-18 | 1949-10-04 | Hercules Powder Co Ltd | Method and apparatus for burning high moisture content fuel |
US2730998A (en) * | 1949-07-11 | 1956-01-17 | Birkner Max | Apparatus for burning solid fuel |
US2793626A (en) * | 1952-06-18 | 1957-05-28 | Babcock & Wilcox Co | Fuel burning apparatus |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3356075A (en) * | 1965-10-12 | 1967-12-05 | Combustion Eng | Method of pulverized coal firing a steam generator and controlling steam temperature |
US4002127A (en) * | 1975-03-13 | 1977-01-11 | Derek Angus | Cyclone structure |
US6269755B1 (en) | 1998-08-03 | 2001-08-07 | Independent Stave Company, Inc. | Burners with high turndown ratio |
RU2648314C2 (en) * | 2015-12-24 | 2018-03-23 | Евгений Михайлович Пузырёв | Boiler with chamber furnace |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB980818A (en) | Method and apparatus for generating vapor | |
US2808012A (en) | Fuel burning apparatus | |
US2907288A (en) | Furnaces | |
US2013565A (en) | Boiler | |
US2087972A (en) | Furnace | |
US2941518A (en) | Apparatus and method for controlling temperature of furnace gases, tube metal and steam | |
US3081748A (en) | Forced flow fluid heating unit | |
US2976855A (en) | Combustion apparatus for low heat value fuel | |
US3115120A (en) | Apparatus for burning low heat value fuels | |
US3580718A (en) | Method for the utilization of hot waste gases from furnaces of metallurgical works | |
US2498761A (en) | Fuel burning apparatus | |
US3274961A (en) | System for heating air and drying fuel | |
US2851018A (en) | Steam generating unit with corner fired furnace and gas recirculation | |
US2921565A (en) | Steam generating and superheating unit with downshot burners and gas recirculation temperature control | |
NO151947B (en) | Steam boiler with swirl layer fireplace | |
US2709424A (en) | Vapor generator furnace | |
US2860613A (en) | Steam generating unit with corner fired furnace and gas recirculation | |
US2918024A (en) | Fuel burning method | |
US2902010A (en) | Radiant tubular heat exchanger | |
US1728571A (en) | Apparatus for insuring complete combustion in industrial furnaces | |
US3207134A (en) | Steam generating unit | |
US2057622A (en) | Mechanical stoker | |
US1153561A (en) | Oil-burning smelting-furnace. | |
US2632427A (en) | Steam boiler supplied with combustion gases at elevated pressure | |
US3153402A (en) | Steam generator |