US 3299940 A
Description (OCR text may contain errors)
1967 A. J. PHILLIPS ETAL 3,
BURNER STRUCTURE Original Filed June 22, 1963 3 Sheets-Sheet 2 INVENTORS QLBERT J. PHILLIPS RICHQRD BAH-1E FITTOENEV Jan. 24, 1967 J. PHILLIPS ETAL 3,299,946
BURNER STRUCTURE Original Filed June 22, 1963 3 Sheets-Sheet INVENTORS ALBERT J PHILLIPS QIQHARD Emma HTTOENEY 3,299,940 BURNER STRUCTURE Albert .I. Phillips, Plainfield, and Richard Baler, New Brunswick, N.J., assignors to American Smelling and Refining Company, New York, N.Y., a corporation of New Jersey Original application June 22, 1963, Ser. No. 204,413, now Patent No. 3,199,977, dated Aug. 10, 1965. Divided and this application June 9, 1965, Ser. No. 462,665 2 Claims. (Cl. 158109) This application is a divisional application of our copending application Serial No. 204,413 filed June 22, 1963, now Patent No. 3,199,977, granted August 10, 1965, which is incorporated herein by reference.
This invention relates to a burner structure for melting copper with hot gases in a vertical furnace without incorporating unwanted amounts of oxygen into the copper during the melting.
The burner structure of the invention is illustrated in the acompanying drawings. It should be understood, however, that the drawings are given for purposes of illustration'and that the invention in its broader aspects is not limited thereto.
In the drawings:
FIG. 1 is an enlarged vertical sectional view showing the burner assembly;
FIG. 2 is a vertical section of a portion of a preferred burner body;
FIG. 3 is a horizontal section view taken along line 1fi1tt of FIG. 2.
As shown in FIG. 1, the burner body 4 is comprised of a section 50 for uniting a stream of fuel and a stream of an oxygen-containing gas to form a unit stream and for introducing the unit stream into igniter section 51. The burner body is also provided with combustion section 52 fabricated of a suitable refractory material and mounted on annular flange 53 against shoulder 54 of igniter section 51. The igniter section is also provided with an annular refractory ring 56 and annular refractory sleeve 57 which is adapted to form, with ring 56, a throat 55 in section 51. Bar 58 may be disposed in the throat and a conventional electrically activated spark plug 59 for igniting the unit stream may be mounted on the side of section 51 with the inner end of the spark plug disposed adjacent bar 58 shown. The combination of the throat and bar 58 are especially useful in maintaining combustion of the unit stream in section 52, particularly when the unit stream is moved through the burner body at a high velocity. Section 51 is also provided with openings 69 and 70 for taking samples of the unit stream; such openings being normally closed by plugs 71. Instead of employing ignition means such as spark plugs 59, the unit stream may be ignited from the inside of the furnace, although such a pro cedure is not preferred.
Section 59 has an annular manifold portion 66, sleeve 61, bend or elbow portion 62, orifice plate 63 and observation port 64 provided with transparent eye piece 65. Sleeve 61, which abuts shoulder 66 and the left end of section 51, cooperates with annular portion 60 to provide a manifold for introducing the smaller of the two streams to be united (usually the fuel stream) from pipe 36 through openings 67 into uniting chamber 68; the size and distribution of openings 67 about the periphery of the sleeve being selected to control entry of the fluid into the chamber. The larger stream (usually the air or oxygen containing gas) is introduced to chamber 68 from pipe 29 through the orifice in plate 63 and bend portion 62.
In operating the burner body, it was found that the total oxygen content of samples of the unit stream taken at different points in plane AA through openings 69 and 76 were not the same. It was also found that differences in the total oxygen content found in samples of the unit stream taken at the same or different points in plane AA could be increased or decreased by shifting orifice plate 63 in its plane across the air stream at the inlet end of bend portion 62 (see FIG. 3) so as to change the position of orifice 72 and cause the air to impinge at a different angle upon bend portion 62. However, when orifice plate 63 was relocated to a position at the outlet end of bend portion 62 immediately in front of the left end of sleeve 61 with the plane of the orifice perpendicular to the axis of the sleeve, relatively large differences in total oxygen content in plane AA in the unit stream were again found but shifting the orifice plate across the path of the larger stream had no appreciable effect on the differences in total oxygen content found in plane AA of the unit stream. Moreover, it was found that any pattern of variation in total oxygen content found across plane AA persisted in the unit stream in its passage through the remainder of the burner body 4.
Accordingly, in operating the burner body, the larger stream of the two streams to be united is conducted to the burner body through an orifice into a bend leading to the uniting chamber, the larger stream is impinged upon a curved surface in the bend to deflect the stream into the uniting chamber and the position of the orifice is shifted to change the angle of impingement of the stream upon the curved surface so as to control variations in the total oxygen content across the path of the unit stream ejected from the burner. It has been found that least variation in such total oxygen content is obtained when substantially all of the larger stream passing through orifice 72 impinges on the curved surface of elbow 62 so that the smallest angle, between the path of flow of said stream and any tangent to that portion of the curved surface upon which the stream impinges, is greater than 45 degrees; and in which the smallest angle with any tangent to that portion of the curved surface upon which a major portion of the stream impinges, is greater than 65 degrees. Thus, as illustrated in FIG. 2, line 73 which is drawn from the left side of orifice 72 parallel to the longitudinal axis 74 of the inlet portion of elbow 62 represents the left side of the path of flow of the larger stream. As shown, the angle between line 73 and the tangent to the curved surface when the latter is intersected by line 73 is greater than 45 degrees (illustrated by the angle B) and the angle C between the orifice axis 74 and the tangent to the curved surface where the latter is intersected by orifice axis 74 is greater than 65 degrees. In addition, it was found that the distance of the fuel inlet openings 67 from the orifice plate 63 affects the sensitivity of the control afforded by shifting the orifice plate 63 in that, as such distance is increased, the sensitivity to shifts in the orifice plate is decreased. Preferably, all of the openings 67 are located within about a foot of the orifice plate as measured along the line 77 generated by the largest internal radius of the elbow and more preferably, as close as practicable thereto.
As shown in FIG. 1, the pipe 29 for conducting the larger stream (air) to the burner body 4 is provided with a valve 80 for controlling the amount of air delivered at positive pressure to the burner body. Likewise, the pipe 36 for conducting the smaller stream (fuel) to the burner body is provided with a valve 81 for controlling the amount of fuel delivered at positive pressure to the burner body. Also, as shown in FIG. 1 the pipe 36 may be provided with a conventional diaphragm controlled valve 85 controlled by a conventional diaphragm means 86 which is provided with diaphragm 87. The diaphragm means is also provided with tube 88 leading from inside pipe 29 to the space above the diaphragm in the diaphragm means so as to communicate the pressure of the air in pipe 29 to the diaphragm. Such an arrangement employing a positive pressure in the fuel and air delivered to uniting chamber 68 is preferred since, by its use, the fuel in pipe 36 ahead of valve 81 is maintained at the same pressure as the air in pipe 29 ahead of orifice plate 63 whereby the ratio of the fuel to the air delivered to the burner, especially when the firing rate of the burner is changed, is more readily controlled to a desired value than the control afforded by an arrangement in which the smaller stream is introduced into chamber 68 by inspiration. Thus, for example, to increase the firing rate of the burner, the pressure of the air in pipe 29 upstream of orifice 63 is increased by opening valve 80. The diaphragm means 86 automatically provides the same pressure in line 36 upstream of valve 81 so that the same ratio of fuel to the air is maintained in the unit stream without changing the setting of valve 81.
What is claimed is:
1. In a burner body,a burner section, a uniting section open at two opposite ends for uniting a stream of fuel and a stream of an oxygen containing gas and delivering the united stream to the burner section, one of said two streams to be united in said uniting section being larger than the other, said uniting section being attached at one of its open ends to said burner section, a bend section open at each end for delivering to the uniting section the larger of the two streams to be united therein, said bend section being attached at one open end to said uniting section, an orifice plate having an orifice therein for delivering the larger of said two streams into said bend section, said orifice plate being movably mounted in the other end of said bend section for shifting the position of said orifice, means for delivering the smaller of said two streams into said uniting section about the periphery thereof adjacent said bend section.
2. In a burner assembly, a burner section, a uniting section open at two opposite ends for uniting a stream of fuel and a stream of an oxygen containing gas and delivering the united stream to the burner section, said stream of oxygen containing gas being larger than said stream of fuel, said uniting section being attached at one of its open ends to said burner section, a bend section having a curved portion therein and being open at each end for delivering to the uniting section the larger of the said two streams to be united therein, said bend section being attached at one open end to the other end of said uniting section, an orifice plate having an orifice therein for delivering said larger stream of said two streams to the curved portion of said bend section, said orifice plate being disposed in said bend section in a position in which said larger stream is delivered by said orifice therein to impinge upon said curved portion in a path of flow which is angularly disposed to the surface of said curved portion, the angle between said path of flow and any tangent to the surface of said curved portion upon which said stream impinges being greater than for substantially all of the impinging stream and also being greater than for a major portion of the impinging stream, a plurality of orifice means in said uniting section for delivering the smaller of said two streams into said uniting section, said orifice means being spaced about the periphery of said uniting section adjacent to said bend section, each of said orifice means being disposed in said uniting section within about a foot of said orifice plate in said bend section, means for delivering said smaller stream under positive pressure to said orifice means, and separate means for delivering said larger stream under pressure to said bend section.
References Cited by the Examiner UNITED STATES PATENTS 2,205,983 6/ 1940 Kraber.
2,244,821 6/1941 Bloom 158-l 18 X 2,610,675 9/1952 Downe 158*116 X 2,632,501 3/1953 Clark 158ll X JAMES W. WESTHAVER, Primary Examiner.