Flare pilot and flare pilot with ignitor assembly

Abstract

In one aspect a pilot assembly is disclosed for use with a flare having a first flare stack and a second flare stack, each having discharge ends. The pilot assembly comprises a pilot nozzle assembly, a pilot inlet pipe having a pilot fuel inlet, and a pilot ignition system. The pilot nozzle assembly comprises a connecting member, a pilot nozzle inlet, a first pilot nozzle and a second pilot nozzle. The pilot nozzle assembly can direct a quantity of pilot gas received via the pilot inlet pipe out through the first and second pilot nozzles. The first and second pilot nozzles may both be positioned adjacent the discharge end of either one of the first or second flare stacks. Alternatively, the first pilot nozzle may be positioned adjacent the first flare stack's discharge, and the second pilot nozzle may be positioned adjacent the second flare stack's discharge end.

Claims

1. A pilot assembly (100) comprising: a pilot nozzle assembly (102); a pilot inlet pipe (110) having a pilot fuel inlet (120); and a pilot ignition system (30); wherein the pilot nozzle assembly (102) comprises: a connecting member (103); a single pilot nozzle inlet (104); and a plurality of nozzle outlets (106a, 106b); and at least two pilot nozzles (102a, 102b); at least one flame front nozzle (36); wherein the pilot nozzle assembly (102) is in fluid communication with said pilot inlet pipe (110); wherein said pilot assembly (100) further comprises a flame front deflector (130) provided between the at least two pilot nozzles (102a, 102b); and wherein the flame front deflector (130) is positioned within the pilot assembly (100) to deflect a flame front FF from said at least one flame front nozzle (36) towards said pilot nozzles (102a, 102b).

2. The pilot assembly (100) of claim 1 wherein the at least two pilot nozzles (102a, 102b) each terminate in one of said plurality of nozzle outlets (106a, 106b); and wherein the connecting member (103) comprises a plurality of conduits (103a, 103b) fluidly connecting the pilot nozzle inlet (104) and the pilot nozzles (102a, 102b).

3. The pilot assembly (100) of claim 2 wherein the at least two pilot nozzles (102a, 102b) each further comprise at least one flame front opening (108).

4. The pilot assembly (100) of claim 3 wherein the pilot ignition system (30) further comprises: a flame front generator (32); and a single ignition line (34).

5. The pilot assembly (100) of claim 4 wherein the connecting member (103) receives a quantity of pilot gas from said pilot inlet pipe (110) via the single pilot nozzle inlet (104); wherein the connecting member (103) then directs substantially all of said quantity of pilot gas to the at least two pilot nozzles (102a, 102b) via the plurality of conduits (103a, 103b); and wherein the at least two pilot nozzles pilot nozzles (102a, 102b) then direct substantially all of said quantity of pilot gas out through their respective nozzle outlets (106a, 106b).

6. A pilot assembly (100) for use with a flare stack (10) having a first flare stack (10a) and a second flare stack (10b), each of the first flare stack (10a) and a second flare stack (10b) comprising a flare (12) having a discharge end (18), the pilot assembly (100) comprising: a pilot nozzle assembly (102); a pilot inlet pipe (110) having a pilot fuel inlet (120); and a pilot ignition system (30); wherein the pilot nozzle assembly (102) comprises: a connecting member (103); a single pilot nozzle inlet (104); and a plurality of nozzle outlets (106a, 106b); at least one flame front nozzle (36); wherein the pilot nozzle assembly (102) is in fluid communication with said pilot inlet pipe (110); wherein the pilot nozzle assembly (102) further comprises a first pilot nozzle (102a) and a second pilot nozzle (102b); wherein said pilot assembly (100) further comprises a flame front deflector (130) between the first pilot nozzle (102a) and the second pilot nozzle (102b); wherein the connecting member (103) comprises a plurality of conduits (103a, 103b) fluidly connecting the pilot nozzle inlet (104) to the first pilot nozzle (102a) and the second pilot nozzle (102b); and wherein the flame front deflector (130) is positioned within the pilot assembly (100) to deflect a flame front FF from said at least one flame front nozzle (36) towards said pilot nozzles (102a, 102b).

7. The pilot assembly (100) of claim 6 wherein the first pilot nozzle (102a) is positioned adjacent the discharge end (18) of the first flare stack (10a); and wherein the second pilot nozzle (102b) is positioned adjacent the discharge end (18) of the second flare stack (10b).

8. A pilot nozzle assembly (102) for use with a pilot assembly (100) of a flare stack (10) having a flare (12) with a discharge end (18), the pilot nozzle assembly (102) comprising: a connecting member (103); a single pilot nozzle inlet (104); a plurality of nozzle outlets (106a, 106b); at least two pilot nozzles (102a, 102b) each terminating in one of said plurality of nozzle outlets (106a, 106b); and at least one flame front nozzle (36); wherein the connecting member (103) comprises a plurality of conduits (103a, 103b) fluidly connecting the pilot nozzle inlet (104) and the pilot nozzles (102a, 102b); wherein said nozzle assembly (102) further comprises a flame front deflector (130) between the first pilot nozzle (102a) and the second pilot nozzle (102b); wherein said plurality of nozzle outlets (106a, 106b) may be directed to said discharge end (18) of the flare (12)); and wherein the flame front deflector (130) is positioned within the pilot assembly (100) to deflect a flame front FF from said at least one flame front nozzle (36) towards said pilot nozzles (102a, 102b).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Referring to the drawings, several aspects of the present invention are illustrated by way of example, and not by way of limitation, in detail in the figures, wherein:

(2) FIG. 1 is a perspective view of a dual flare stack having PRIOR ART flare pilots;

(3) FIG. 2 is a top perspective view of the PRIOR ART flare pilots in the dual flare stack of FIG. 1;

(4) FIG. 3 is a close-up, top-side, perspective view of PRIOR ART flare pilot for flare stack 1 of the dual flare stack of FIG. 1;

(5) FIG. 4 is a top perspective view of one embodiment of a flare pilot, shown mounted in multiple locations on a dual flare stack;

(6) FIG. 5 is a close-up view of the top of the dual flare stack of FIG. 4, with the wind shrouds removed so as to more clearly show the novel flare pilots of the present invention;

(7) FIGS. 6 and 7 are close-up, side perspective views of the flare pilots of the embodiment of FIG. 4;

(8) FIGS. 8a and 8b are perspective views of a second embodiment of a flare pilot nozzle of the invention;

(9) FIGS. 9a and 9b are perspective views of a third embodiment of a flare pilot nozzle of the invention;

(10) FIGS. 10a and 10b are perspective views of a fourth embodiment of a flare pilot nozzle of the invention;

(11) FIGS. 11a, 11b and 11c are bottom, right-side and top views of a flare pilot illustrating a fifth embodiment of a flare pilot nozzle of the invention;

(12) FIGS. 12a, 12b and 12c are bottom, right-side and top views of a flare pilot illustrating a sixth embodiment of a flare pilot nozzle of the invention;

(13) FIG. 13a is a side perspective view of a seventh embodiment of a flare pilot with ignitor assembly, shown mounted in between the two flares of a dual flare stack;

(14) FIGS. 13b-13e are a close-up perspective views of the dual flare stack of FIG. 13a, with the wind shroud removed so as to more clearly show the novel flare pilot and ignitor assembly of the present invention;

(15) FIGS. 13f-13g are a close-up perspective views of the dual flare stack of FIG. 13a, showing the flare pilot and ignitor assembly of the present invention being ignited by a flame front and with the pilot flame lit;

(16) FIGS. 14a-14b are top views of the flare pilot embodiment of FIGS. 11a-11c, showing a flame front (FIG. 14a) lighting the pilot's pilot flame (FIG. 14b); and

(17) FIGS. 15a-15b are top views of the flare pilot embodiment of FIGS. 12a-12c, showing a flame front (FIG. 15a) lighting the pilot's pilot flame (FIG. 15b);

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(18) The following description is of preferred embodiments by way of example only and without limitation to the combination of features necessary for carrying the invention into effect. Reference is to be had to the Figures in which identical reference numbers identify similar components. The drawing figures are not necessarily to scale and certain features are shown in schematic or diagrammatic form in the interest of clarity and conciseness.

(19) A first embodiment of a pilot assembly 100 of the present invention is shown in FIGS. 4-7. The pilot assembly 100 preferably comprises a pilot nozzle assembly 102, a single pilot inlet pipe 110 having a pilot fuel inlet 120, and a pilot ignition system 30. The pilot nozzle assembly 102 is in fluid communication with said single pilot inlet pipe 110. During operation, and as conventional, the pilot assembly 102 receives pilot fuel or pilot gas from a gas source (not shown) via pilot inlet pipe 110 and pilot fuel inlet 120; e.g. via a fuel hose (not shown) connecting the gas source to the pilot fuel inlet 120. Pilot ignition system 30 preferably comprises a flame front generator 32, a single ignition line 34, and at least one flame front nozzle 36. During operation, pilot ignition system 30 can be actuated to ignite the pilot fuel or pilot gas in a substantially conventional manner (via a flame front) and light the pilot flame (PF).

(20) Pilot nozzle assembly 102 preferably comprises a body or connecting member 103, a single pilot nozzle inlet 104 and a plurality of nozzle outlets 106. More preferably, pilot nozzle assembly 102 comprises dual pilot nozzles 102a, 102b each terminating in their respective nozzle outlet 106a, 106b. Body or connecting member 103 may comprise a plurality of legs or conduits 103a, 103b between inlet 104 and the nozzles 102a, 102b. One or more thermal well guides or inlets 150 may be provided on body 103 to receive a conductive wire or lead 152 to connect a thermocouple that may be within assembly 102 to the pilot ignition system (see also FIGS. 14a-15b). As illustrated in FIGS. 4-7, connecting member 103 and pilot nozzles 102 are each preferably generally tubular members. Pilot nozzle assembly 102 is preferably made from metal, steel or any other suitable material that provides adequate strength and durability to allow said assembly 102 to operate as a pilot and withstand the heat, flames and high temperatures typically encountered by the assembly 102 during flare stack 12 operations.

(21) Preferably, the pilot nozzle assembly 102 of the embodiment shown in FIGS. 4-7 preferably comprises a body or connecting member 103 to fluidly connect plurality of pilot nozzles 102a, 102b to said pilot nozzle inlet 104 (via legs or conduits 103a, 103b). Body 103 preferably receives pilot gas from said single pilot inlet pipe 110 (via inlet 104) and then directs all, or substantially all, of said pilot gas to said plurality of pilot nozzles 102a, 102b, via legs or conduits 103a, 103b. The plurality of pilot nozzles 102a, 102b then direct all, or substantially all of said pilot gas out through their respective nozzle outlets 106a, 106b. More preferably, the body 103 and plurality of pilot nozzles 102a, 102b are of such dimensions (including inside diameter passages) so as to substantially evenly direct said pilot gas to each of said plurality of pilot nozzles 102a, 102b and their respective outlets 106a, 106b; i.e. so as to have the amount of pilot gas flow (volume, flow rates and pressures) be substantially the same at each of the plurality of nozzle outlets 106.

(22) The plurality of pilot nozzles 102a, 102b may each be provided with one or more flame front openings 108 to allow some of the pilot gas to exit the pilot nozzles 102a, 102b prior to the bulk of said pilot gas being directed to discharge from outlets 106a, 106b and/or to allow a flame front FF (which may exit from flame front nozzle 36) to enter into the interior of said nozzles 102a, 102b, thereby facilitating ignition of the pilot gas by said flame front FF during operation and ignition procedures and light the pilot flame PF.

(23) A plurality of flare pilot assemblies 100 may be provided and mounted on one or more flare stacks 10 having a flare 12 with a discharge end 18. Flare 12 may be connected to stack 14 by means of a flanged connection 16. A gas stripper 17 is preferably provided to direct some of the waste fluids within the flare 12 to the nozzle assembly 100, to assist with the combustion and ignition of said waste fluids by the pilot assemblies 100. A wind shroud 19 is preferably provided to reduce or eliminate flame-outs of the pilot flame PF during bad/stormy weather. The flare stack 10 may be a dual flare stack, as shown in FIGS. 4-7 and FIGS. 13a-13g, comprising a first flare stack 10a and a second flare stack 10b. In the embodiments of FIGS. 4-7 and in FIGS. 13a-13g, the first flare stack 10a and a second flare stack 10b each comprise a flare 12 having a discharge end 18 and connected to a stack 14 via a flanged connection 16.

(24) In the embodiments of FIGS. 4-7, three flare pilot assemblies 100a, 100b, 100c are provided—one such assembly 100a on the first flare stack 10a and two such assemblies 100b, 100c on the second flare stack 10b (see FIG. 4). Each of these flare pilot assemblies 100a, 100b, 100c is rollably mounted in a conventional manner to their respective flare stack 10a,10b; i.e. by means of a pilot retraction system 40, comprising a pilot retracting track 42 (see FIG. 4). A conventional winch, cable and pulley system (not shown) is employed to adjustably position the flare pilot assemblies 100a, 100b, 100c between the discharge end 18 of the flare stack 10 (e.g. during operation) and a lowered position (e.g. during maintenance). Since there are three (3) flare pilot assemblies 100a, 100b, 100c, there are three (3) corresponding pilot retraction systems 40 and pilot retracting tracks 42 (one on the first flare stack 10a, and two on the second flare stack 10b).

(25) Advantageously, the flare pilot assemblies 100a, 100b, 100c of this embodiment provide for a total of six (6) separate pilot nozzles 102 and nozzle outlets 106; and the ability to direct six (6) pilot flames over the discharge ends 18—i.e. two (2) on the first flare stack 10a, and four (4) on the second flare stack 10b. More advantageously, only three (3) pilot retraction systems 40 and pilot retracting tracks 42 are needed to mount these six nozzles 102. Therefore, as compared to the prior art system shown in FIG. 2, where five (5) pilot nozzles were mounted on five (5) pilot retracting systems, this embodiment not only provides additional pilot nozzles (six nozzles versus five in the prior art version), but requires significantly less pilot retracting systems and retracting racks (three versus five).

(26) Now referring to the embodiment of FIGS. 13a-13g, a single flare pilot assembly 100 is shown mounted on a dual flare stack. The flare pilot assembly 100 is rollably mounted in a conventional manner to one of the flare stacks 10a; i.e. by means of a single pilot retraction system 40, comprising a pilot retracting track 42 (see FIG. 13a). A conventional winch, cable and pulley system (not shown) is employed to adjustably position the flare pilot assembly 100 between the discharge end of the flare stack 18 (e.g. during operation) and a lowered position (e.g. during maintenance). The flare pilot assembly 100 of this embodiment provides two separate pilot nozzles 102a, 102b and two nozzle outlets 106a, 106b; and the ability to direct a pilot flame PF' over the discharge ends 18 of each of the two flare stacks 10a,10b. Advantageously, only a single pilot retraction system 40 is required to mount two separate pilot nozzles 102a, 102b over two flare stacks 10a, 10b.

(27) In the embodiment of FIGS. 13a-13g, and to facilitate ignition of the pilots, the flame front nozzle 36 further comprises a nozzle body or connecting member 33, a single nozzle inlet 33i, a first leg 33a, a second leg 33b and a plurality of nozzle outlets 36a, 36b. More preferably, flame front nozzle 36 comprises dual nozzle outlets 36a, 36b each oriented so as to direct a flame front FF, FF′ onto each of the associated nozzle outlet 106a, 106b of the pilot nozzle assembly 102 (see FIGS. 13f, 13g). Flame front nozzle body 33, first leg 33a, second leg 33b and flame front nozzles 36 are each preferably generally tubular members. Flame front nozzle 36, first leg 33a, second leg 33b and body 33 are preferably made from metal, steel or any other suitable material that provides adequate strength and durability to allow them to withstand the heat, flames and high temperatures typically encountered during flare stack and pilot ignition operations.

(28) Preferably nozzle body 33 fluidly connects plurality of nozzle outlets 36a, 36b to the nozzle inlet 33i, via first and second legs 33a, 33b respectively. Nozzle body 33 preferably receives a flame front from the ignition line 34 (via nozzle inlet 33i) and then directs all, or substantially all, of said flame front to said plurality of nozzle outlets 36a, 36b (via first and second legs 33a, 33b). More preferably, the nozzle body 33, first and second legs 33a, 33b and plurality of nozzle outlets 36a, 36b are of such dimensions (including inside diameter passages) so as to substantially evenly direct a flame front (from the ignition line 34) out from each of said plurality of nozzle outlets 36a, 36b so as to produce a plurality of flame front FF, FF′.

(29) Advantageously, first and second legs 33a, 33b may be of such dimensions and orientations so as to provide a flame front nozzle outlet 36a, 36b in close proximity to a corresponding or associated pilot nozzle outlet 106a, 106b, thereby ensuring that a flame front FF, FF′ is directed to each of said pilot nozzle outlets 106a, 106b during pilot ignition operations (see FIGS. 13f-13g), so as to ensure reliable lighting of all of the nozzle outlets 106 of the pilots. Preferably, flame front nozzle outlets 36a, 36b are positioned within 2 inches from each of the associated pilot nozzle outlet 106a, 106b, so as to increase the likelihood that the flame fronts FF, FF′ will successfully ignite the pilot to produce pilot flames PF, PF′ from each of said pilot nozzles 102a, 102b.

(30) In the embodiment of FIGS. 14a-15b, and to facilitate ignition of two adjacent pilot nozzles 102a, 102b via a single flame front nozzle 36, said single flame front nozzle 36 is positioned so as to direct the flame front FF at a point B substantially between and adjacent to said pilot nozzles 102a, 102b (as illustrated), and preferably no further than 2 inches from each of said pilot nozzles 102a, 102b, so as to increase the likelihood that a flame front FF will successfully ignite the pilot to produce pilot flames PF, PF′ from each of said pilot nozzles 102a, 102b. Preferably, and as shown in the embodiment of FIGS. 15a-15b, a flame front deflector 130 is provided between said pilot nozzles 102a, 102b to direct or deflect the flame front FF towards both said pilot nozzles 102a, 102b. Flame front deflector 130 is preferably a planar member made from metal, steel or any other suitable material that provides adequate strength and durability to allow it to withstand the heat, flames and high temperatures from a flame front FF. A flame front deflector 130 is similarly provided in the embodiments of FIGS. 8a-9b.

(31) Those of ordinary skill in the art will appreciate that various modifications to the invention as described herein will be possible without falling outside the scope of the invention. In the claims, the word “comprising” is used in its inclusive sense and does not exclude other elements being present. The indefinite article “a” before a claim feature does not exclude more than one of the features being present.