BURNER

Abstract: A burner which can be used to dispose of heavy crude waste oil and petroleum products contaminated with drilling mud. The burner includes a nozzle assembly (35) having means (40, 54, 68, 74, 75) for internally mixing atomizing fluid with the primary fluid being disposed of by the burner. If desired, means (38) are provided for injecting a secondary fluid into the nozzle assembly (35) to improve the combustion of primary fluid. Means (73) are provided for directing atomizing fluid to form a converging conical pattern exterior of the burner tip (51a). In the alternative, secondary fluid can be injected into the compound mixture of atomizing fluid and primary fluid exterior to the nozzle assembly (35).

Description: BURNER This invention relates to burners for combustion of hydrocarbon fluids and is particularly suitable for use during drilling and/or production testing of oil and gas wells. U. -S. Patents 3,797,992 titled Crude Oil Burner; 3,861,857 titled Flammable Liquid Waste Burner; and 3,995,985 titled Crude Oil Burner, d-isclose bti±ήers which are designed for use while testing oil and gas well pro¬ duction. U. S. Patents 3,995,985 and 3,861,857 further disclose the use of flammable gas to boost the combustion - of waste liquids and to produce a "smokeless" burn of heavy crude oil. Frequently, hydrocarbons from downhole formations will become contaminated by drilling fluids (mud) . Burning is one method for disposing of the resulting mixture. Also, many types of crude oil are very difficult to burn as produced at the well surface. U. S. Patents 3,914,094 titled XVaste Oil Burner; 4,141,505 titled Heavy Fuel Oil Nozzle; and 4,155,702 titled Burner disclose various devices which aid the combustion of hydrocarbon fluids having less than ideal burning characteristics. These patents describe various problems associated with burning heavy crude or waste oil. U. S. Patent 4,011,995 titled Burner Nozzle Assembly discloses a nozzle assembly which internally mixed compressed gas with flammable fluids. The nozzle assembly uses the same compressed gas to shape and control the compound mixture of gas and flammable fluid after it exits the nozzle assembly. The present invention provides a burner for combustion of liquid hydrocarbons comprising: a nozzle assembly having a longitudinal passageway therethrough for receiving a primary fluid from a source exterior to the burner and spraying the primary fluid into an open air flame; chamber means surrounding the longitudinal passageway for receiving atomizing fluid from a source exterior to the burner; means for directing the atomizing fluid from the chamber means to form a conical pattern around the exit end of the longitudinal passageway; a throat means which partially defines the longitudinal passageway; and the length of the throat means selected to extend into the conical pattern formed by the atomizing fluid exiting the chamber means. The invention further provides a nozzle assembly for use in a burner which disposes of primary fluid by open air combustion comprising: a receiver and throat means with a longitudinal passageway extending through each; a portion of the throat means rotatably disposed within the receiver; a burner tip on the end of the throat means opposite the receiver; the burner tip defining the exit end of the longitudinal passageway; chamber means for receiving atomizing fluid from a source exterior to the burner; the chamber means mounted on the exterior of the receiver and throat means; a plurality of ports in the chamber means spaced radially from each other and directed towards the burner tip to produce a converging conical flare of atomizing fluid extending from the chamber means; and the burner tip extending into the conical flare of atomizing fluid. In the accompanying drawings: Figures lA and B are drawings in elevation with portions broken away showing a burner supported on a boom which is in turn attached to a work platform or vessel. The burner comprises one embodiment of a nozzle assembly. OMPI Figures 2A, B, C and D are schematic drawings, in longitudinal section with portions broken away, of the nozzle assembly shown in Figures 1A and B. Figures 3A and B are schematic drawings, in longitudinal section with portions broken away, showing a nozzle assembly incorporating an alternative embodiment. Figure 4 is a drawing, in elevation and reduced in size, of the front of the nozzle assembly shown in Figure 3B. Figure 5 is a drawing in radial section taken along line 5-5 of Figure 3B. Figure 6 is a drawing in longitudinal section taken along line 6-6 of Figure 5. At various times during the drilling, testing, and completion of offshore oil and gas wells, it is necessary to dispose of waste fluids and/or crude petroleum fluids. These fluids are frequently disposed of by burning due to the limited storage capacity of most drill ships or offshore platforms. The cost and difficulty of transporting these fluids to a shore disposal site is generally prohibitive. The term "primary fluid" as used in this patent application means heavy crude oil, waste oil, hydrocarbon fluids contaminated with drilling mud, and/or formation fluids produced while testing wells. In Figures 1A and B a typical work platform 20 such as a drilling vessel, semi-submersible, or jack-up is shown with boom 21 extending therefrom. Burner 25 is secured near the extreme end of boom 21 opposite from platform 20. Typically, boom 21 can be pivoted and/or elevated as appropriate for the wind and weather conditions. Gas flare 24 extends from the extreme end of boom 21 below burner 25. Flare 24 is used to dispose of any gas produced during well testing. Fluid supply lines 26 through 31 which extend from platform 20 to burner 25 are supported by boom 21. The purpose for each of these OMPI fluid supply lines will be explained later. One method for minimizing visible smoke is to spray water on the flame (not shown) produced by burner 25. Supply line 29 through appropriate connections provides water to water spray ring 33 on the extreme end of burner 25. As explained in U. S. Patent 3,797,992, water sprayed from ring 33 facilitates smokeless combus¬ tion. Burner 25 preferably has three nozzle assemblies 35. The actual number of nozzle assemblies 35 can be varied as required for the volume of fluid disposed of by burner 25. Figures 2A-2D show nozzle assembly 35 in detail. Nozzle assembly 35 includes three concentric flow paths to deliver primary fluid, secondary fluid and an atomizing fluid to longitudinal passageway 40 which extends therethrough. Sometimes, petroleum fluids produced directly from a well are difficult to burn. This is particularly true for high viscosity, heavy crude oil and crude oil contaminated by drilling mud, salt water, etc. To aid in combustion of these primary hydrocarbon fluids, the present invention provides means for injecting a secondary, more highly combustible fluid into the primary fluid being disposed of by burner 25. Diesel fuel is one liquid which can be satisfactorily used as the secondary fluid. Natural gas, methane, kerosene, and other similar petroleum products could be used as the secondary fluid. Diesel fuel is supplied to nozzle assembly 35 via secondary fluid supply line 26 and appropriate connections including threaded opening 26a in connector 36. Secondary fluid is received within hollow cylinder 37. Flow tube means 38 extends from within hollow cylinder 37 to longitudinal passageway 40 to communicate secondary fluid therewith. Appropriately, sized o-rings 42 and 43 and packing means 44 are provided to prevent undesired communication between the secondary fluid and other fluids within nozzle assembly 35. A unique feature is that hollow cylinder 37 can be removed from nozzle assembly 35 by disengaging threaded coupling 45. Flow tube means 38 can be removed from longitudinal passageway 40 by disengaging locking cylinder 46 after removing cylinder 37. This feature allows for ease of maintenance of nozzle assembly 35. Also, a properly sized cap or end closure (not shown) can be attached to threads 47 to allow operation of nozzle assembly 35 with flow tube means 38 removed. As will be demonstrated later, the end of longitudinal passageway 40 which receives flow tube means 38 can be sealed by plug means 70. See Figure 3B. Primary fluid is supplied to nozzle assembly 35 via supply line 31 and appropriate connections including opening 31a. The primary fluid is received within cylin¬ drical housing 48 which is formed from two subassemblies 48a and 48b for ease of manufacture and assembly. Flow tube means 38 is concentrically positioned within cylindri- cal housing 48. Atomizing fluid is supplied to nozzle assembly 35 by atomizing fluid supply line 28 and appropriate connections including opening 28a. Compressed air is preferably used as the atomizing fluid in nozzle assembly 35. As will be explained later in more detail, atomizing fluid (air) mixes with the primary fluid in longitudinal passageway 40 to facilitate combustion. Also, the same atomizing fluid is used to shape and control the spray of the compound mixture (air, primary fluid and secondary fluid) which exits from longitudinal passageway 40. Atomizing fluid is received within cylindrical housing 49 from opening 28a. Housing 49 is concentrically aligned with and surrounds housing 48. Housing 49 is a portion of the chamber means which surrounds longitudinal passageway 40 and supplies atomizing fluid thereto. Longitudinal passageway 40 is defined by two subassemblies, nozzle body or receiver 50 and throat means 51. Flow tube means 38 is secured within one end of re¬ ceiver 50. A portion of throat means 51 is secured within the other end of receiver 50. The remainder of throat means 51 extends longitudinally from receiver 50. O-rings 52 and 53 are positioned on the exterior of throat means 51 to prevent undesired fluid communication between longitudinal passageway 40 and the exterior of throat means 51. A plurality of openings 54 extends radially through receiver 50 to allow primary fluid from cylindrical housing 48 to communicate with longitudinal passageway 40. Openings 54 are positioned intermediate the ends of the receiver 50. Preferably, openings 54 are located between the end of flow tube means 38 and the beginning of throat means 51. This configuration allows for more complete mixing of primary and secondary fluids before the resulting mixtures exits from throat means 51. Retaining swage 55 is used to secure receiver 50 and throat means 51 to each other. Swage 55 is basically a hollow cylinder with a reduced inside diameter portion 57 and an enlarged inside diameter portion 63. Flange 56 is provided on the exterior of throat means 51 intermediate the ends thereof. ' Receiver 50 abuts one side of flange 56, and retaining swage 55 abuts the other. Inside diameter portion 57 of swage 55 is slightly larger than the adjacent outside diameter of throat means 51. A plurality of set screws 58 extends through portion 57 of swage 58 to contact throat means 51 and prevent rotation of throat means 51 relative to swage 55 and receiver 50. End 59 of receiver 50 has recess 60 to receive o-ring 53 and flange 56 therein. End 59 has a larger diameter than the other portions of receiver 50. Adapter sub 61 can be engaged by threads 62 to the enlarged inside diameter portion 63 of swage 55. Adapter sub 61 is a hollow sleeve which can slide over the exterior of receiver 50 except for end 59. Thus, the threaded engagement between adapter sub 61 and swage 55 holds end 59 in contact with flange 56 and o-ring 53 trapped therebetween. Cylindrical housing subassembly 48b is engaged by threads 64 to adapter sub 61. O-ring 65, carried between adapter sub 61 and receiver 50, prevents undesired communication between the primary fluid in cylindrical housing 48 and the atomizing fluid in cylindrical housing 49. End cap 66 is slidably positioned over a portion of swage 55 and engaged by threads 67 to cylindrical housing 49. Swage 55 can slide through circular opening 72 of end cap 66. The inside diameter of end cap 66 is larger than the outside diameter of swage 55 which creates a portion of chamber means 68. Packing means 71 prevents undesired escape of atomizing fluid from chamber means 68. A plurality of ports 73 extends from chamber means 68 through " end cap 66. Ports 73 are formed in a circular pattern spaced radially from opening 72. Longitudinal passageway 40, throat means 51, inside diameter portion. 57 of swage 55 and opening 72 of end cap 66 are concen¬ trically aligned on the same longitudinal axis. The centerline of each port 73 is tapered inwardly to form an acute angle with respect to the centerline of longi¬ tudinal passageway 40. The imaginary point at which the centerline from each port 73 intersects is selected to be longitudinally spaced from the end 51a of throat means 51 which extends from swage 55. Atomizing fluid within chamber means 68 can exit through ports 73 to form a conical pattern around end 51a. The length of throat means 51 is selected to ensure that burner tip or end 51a extends into the conical pattern formed by atomizing fluid exiting ports 73. Thus, ports 73 form a portion of the means for directing the atomizing fluid from chamber means 68 to form a conical pattern around the exit end of longitudinal passageway 40. As previously noted, chamber means 68 surrounds OMPI longitudinal passageway 40 and receives atomizing fluid from a source exterior to burner 25. Chamber means 68 has two separate portions 68a and 68b for ease of manufacture and assembly. Ports 73 extend into portion 68b. A plurality of apertures 93 extends through adapter sub 61 to communicate atomizing fluid between portions 68a and 68b of chamber means 68. Receiver 50 also has a plurality of openings 74 which extend radially through its exterior between o-rings 52 and 53. Throat means 51 also has a plurality of internal injection orifices 75 adjacent to openings 74 in receiver 50. Internal injection orifices 75 and openings 74 cooperate to provide openings between chamber means 68 and longitudinal passageway 40 which allow mixing of atomizing fluid and primary fluid prior to exiting from throat means 51. As previously noted, set screws 58 prevent rotation of throat means 51 relative to swage 55 and receiver 50. To vary the amount of atomizing fluid entering longitudinal passageway 40 from chamber means 68, set screws 58 are loosened and throat means 51 rotated to increase or decrease the radial alignment between holes 74 and internal injection orifices 75 as desired. The centerline of each internal injection orifice 75 forms a compound angle with respect to the longitudinal axis of throat means 51. This compound angle is best shown in Figures 5 and 6. Thus, atomizing fluid entering longitudinal passageway 40 imparts a violent swirling motion to the liquid flowing therethrough. This swirling motion prevents liquid boundary layer buildup within throat means 51 and promotes better mixing of atomizing fluid and primary fluid. The compound angle of orifices 75 significantly improves the ability of burner 25 to dispose of waste oil, heavy crude and/or contaminated petroleum products. Burner 25 and boom 21 are mounted on platform 20 and supply lines 26 through 31 connected therebetween. 1. OMPI The primary fluid being disposed of is pumped through supply line 31 and connection 31a into cylindrical housing 48. Primary fluid flows from housing 48 through openings 54 into longitudinal passageway 40. A secondary fluid such as diesel fuel can be injected into longitudinal passageway 40 via supply line 26 and flow tube means 38. The secondary fluid mixes with the primary fluid within throat means 51 to improve the combustion of the primary fluid. Atomizing fluid is also injected into longitud¬ inal passageway 40 via supply line 28, connection 28a, cylindrical housing 49, chamber means 68, openings 74 and internal injection orifices 75. The atomizing fluid due to its injection angle causes violent swirling and mixing of the primary and secondary fluids. Air is preferably used as the atomizing fluid. The resulting compound mixture of air, primary fluid and secondary fluid exits throat means 51 at greatly increased velocity due to the expansion of the air. Also, violent mixing of air with the primary fluid reduces its effective viscosity and improves its combusion characteristics. Atomizing fluid is also focused on the compound mixture exiting throat means 51 by ports 73. This use of atomizing fluid external to throat means 51 controls the shape of the compound mixture and the resulting flame after the compound mixture is ignited. Atomizing fluid from ports 73 also supplies additional oxygen to facilitate more complete combustion (less smoke) of the primary fluid. An electrical ignitor (not shown) and gas supplied through supply line 30 are used to ignite the compound mixture exiting from throat means 51. If the combustion process is not satisfactory, burner 25 can be secured. Set screws 58 can be loosened to allow rotation of throat means 51 relative to receiver 50. Rotating throat means 51 varies the radial alignment between internal injection orifices 75 and openings 74 OMPI 1PO . to vary the amount of atomizing fluid injected into long¬ itudinal passageway 40. Thus, this embodiment allows nozzle assembly 35 to be easily adjusted for optimum combustion of the particular type of primary fluid being disposed of by burner 35. If secondary fluid is not required, this embodiment allows the removal of flow tube means 38 from longitudinal passageway 40. Plug means 70 can be inserted into receiver 50. A blank end cap (not shown) can be attached to threads 47 and nozzle assembly 35 operated with only primary fluid and atomizing fluid flowing therethrough. An alternative embodiment is shown in Figures 3A, 3B,.4, 5.and 6. Like parts as compared to nozzle assembly 35 have the same numerical designation. Parts which function in the same manner but have a slightly modified design as compared to nozzle assembly 35 have the same numerical designation followed by a " ' ". For example, supply line 26' supplies secondary fluid to nozzle assembly 80 the same as supply line 26 supplies secondary fluid to nozzle assembly 35. The configuration of supply line 26* is slightly modified to accommodate nozzle assembly 80. As shown in Figures 3A and 3B, flow tube means 38 is not contained within nozzle assembly 80. Plug means 70 is secured by snap ring 90 within receiver 50' to prevent undesired primary fluid flow into longitudinal passageway 40. Primary fluid in supply line 31 is communicated with cylindrical housing 48b via elbow 81. If desired, elbow 81 could be replaced by cylindrical housing section 48a and flow tube means 38 inserted into receiver 50" . Snap ring 90 can also be used to secure flow tube means 38 within longitudinal flow passageway 40. Openings 54 are provided in receiver 50' to communicate primary fluid into longitudinal passageway 40. Atomizing fluid is directed from connection 28a into longitudinal passageway 40 via chamber means 68. Figure 6 demonstrates the compound angle of internal injection orifices 75 with respect to the longitudinal axis of throat means 51. Figure 5 illustrates how rotation of throat means 51 relative to receiver 50 ' can vary the radial alignment of openings 74 relative to internal injection orifices 75. The alignment shown in Figure 5 results in the maximum flow of atomizing fluid into longidutinal passageway 40. The major variation between nozzle assembly 35 and nozzle assembly 80 is the installation of secondary fluid container 84 on the exterior of end cap 66. Container 84 is generally cylindrical in shape with opening 85 therein to receive end cap 66. Container 84 has the general shape of a toroid. Annular chamber 86 in container 84 receives secondary fluid from supply line 26' via elbow 87. Flat spray nozzles 88 are mounted on the exterior of container 84. Spray nozzles 88 receive secondary fluid from chamber 86 ^ and spray it radially inward towards the compound mixture exiting throat means 51. Thus, chamber 86 and spray nozzles 88 form a portion of the means for injecting secondary fluid into the compound mixture of atomizing fluid and primary fluid after the compound mixture exits from throat means 51. Set screw 89 is used to releasably secure container 84 to the exterior of end cap 66. Burner 25 can be assembled with a plurality of either nozzle assemblies 35 or 80 or a combination of each type if desired.

Claims: CLAIMS 1. A burner for combustion of liquid hydrocarbons comprising: a nozzle assembly having a longitudinal pas¬ sageway therethrough for receiving a primary fluid from a source exterior to the burner and spraying the primary fluid into an open air flame; chamber means surrounding the longitudinal passageway for receiving atomizing fluid from a source exterior to the burner; means for directing the atomizing fluid from the chamber means to form a conical pattern around the exit end of the longitudinal passageway; a throat means which partially defines the longitudinal passageway; and the length of the throat means selected to extend into the conical pattern formed by the atomizing fluid exiting the chamber means. 2. A burner as defined in claim 1, having openings between the chamber means and the longitudinal passageway which allows mixing of the atomizing fluid and the primary fluid prior to exiting from the throat means. 3. A burner as defined in claim 1, further comprising means for injecting a secondary fluid into the longitudinal passageway to allow mixing between the primary fluid and secondary fluid prior to exiting the throat means. 4. A burner as defined in claim 2, further comprising means for injecting a secondary fluid into the compound mixture of atomizing fluid and the primary fluid after the mixture exits from the throat means. 5. A burner as defined in claim 2, wherein the conical pattern formed by the atomizing fluid con- verges on the compound mixture which exits from the throat means. 6. A burner as defined in claim 2, further comprising: a plurality of internal injection orifices formed in the throat means adjacent to the openings in the chamber means; and means for varying the radial alignment between the injection orifices and the openings. 7. A burner as defined in claim 6, further comprising: a hollow cylindrical sleeve comprising the throat means; a flange formed on the exterior of the sleeve intermediate the ends thereof; receiver surrounding a portion of the sleeve and abutting the flange; the long¬ itudinal passageway extending through both the receiver and the throat means; and the chamber means surrounding a portion of the hollow sleeve and abutting the flange. 8. A burner as defined in claim 7, wherein the receiver comprises: a plug means releasably secured within one end of the longitudinal passageway; and means for engaging a flow tube means carrying the secondary fluid into the longitudinal passageway after the plug has been removed. 9. A burner as defined in claim 6, wherein the axis of the internal injection orifices forms an acute angle with respect to the longitudinal axis of the throat means. 10. A nozzle assembly for use in a burner which disposes of primary fluid by open air combustion comprising: a receiver and throat means with a longitudinal passageway extending through each; a portion of the throat means rotatably disposed within the receiver; a burner tip on the end of the throat means opposite the receiver; the burner tip defining the exit end of the longitudinal passageway; chamber means for receiving atomizing fluid from a source exterior to the burner; the chamber means mounted on the exterior of the receiver and throat means; a plurality of ports in the chamber means spaced radially from each other and directed towards the burner tip to produce a converging conical flare of atomizing fluid extending from the chamber means; and the burner tip extending into the conical flare of atomizing fluid. 11. A nozzle assembly as defined in claim TO, further comprising means for internally injecting atomizing fluid from the chamber means into the longitudinal passageway intermediate the ends thereof. 12. A nozzle assembly as defined in claim 10, further comprising: a plurality of openings extending radially through the receiver intermediate the ends thereof; the throat means having a plurality of internal injection orifices adjacent to the openings in the receiver; and means for varying the radial alignment between the injection orifices and the openings. 13. A nozzle assembly as defined in claim 11, wherein the internal injection means further comprises: means for regulating the viscosity of the resulting compound mixture of atomizing fluid and primary fluid; and means for the atomizing fluid to control the shape of the compound mixture as it exits the burner tip. 14. A nozzle assembly as defined in claim 12, wherein the centerline of each internal injection orifice forms a compound angle with respect to the longitudinal axis of the longitudinal passageway. 15. A nozzle assembly as defined in claim 11, further comprising means for injecting a secondary fluid into the compound mixture of atomizing fluid and the primary fluid after the mixture exits from the burner tip. 16. A nozzle assembly as defined in claim 15, wherein the means for injecting secondary fluid comprises: a container mounted on the exterior of the chamber means; means for communicating secondary fluid between a source exterior to the nozzle assembly and the container; and a plurality of spray nozzles mounted on the exterior of the container to direct secondary fluid into the compound mixture.

Inventors: BAYH RUSSELL I III, BAYH, RUSSELL, I., III
Applicants: OTIS ENG CO, OTIS ENGINEERING CORPORATION
Application year: 1983
Main classification: F23D11
IPC codes: F23D11, F23D17