US3669628A - Burner and feedstock injection assembly for carbon black reactor - Google Patents

Abstract

A BURNER AND FEEDSTOCK INJECTION ASSEMBLY FOR A CARBON BLACK REACTOR HAVING THREE CONCENTRIC PIPES: A CENTER PIPE FOR FEEDSTOCK; A SECOND PIPE, SURROUNDING THE CENTER PIPES; A THIRD PIPE, SURROUNDING THE SECOND PIPE; AND A PLURALITY (PREFERABLY THREE) OF FUEL-OIL PIPES, DISDOSED WITHIN THE ANNULUS BETWEEN THE SECOND AND THIRD PIPES; THE ENDS OF EACH OF THESE FUEL-OIL PIPES BEING EQUIPPED WITH A SPRAY NOZZLE INCLINDED AT AN ANGLE WITH RESPECT TO THE AXIS OF THE CENTER PIPE. THESE FUEL-OIL PIPES ARE FOR THE INTRODUCTION OF COMBUSTION FUEL INTO THE REACTOR. PREFERABLY, THE ASSEMBLY ALSO INCLUDES A SUBSTANTIALLY CONE-SHAPED FLAMEHOLDER DEVICE MOUNTED CONCENTRICALLY ABOUT THE THIRD PIPE AT THE END THEREOF, SUCH CONE FLARING OUTWARDLY TOWARD THE INTERIOR OF THE REACTOR, SUCH CONE BEING COMPRISED OF A PLURALITY OF VANES OR LOUVERS EACH OF WHICH IS TWISTED AT THE OUTER ENDS THEREOF.

Description

June 13, 1972 B. F. LATHAM. JR., ETAL BURNER AND FEEnsTocx-1NJEcT1ox ASSEMBLY FOR CARBON BLACK REACTOR Filed July 31, 1970 IIII INVENTORS WlLLlAM B. CRULL BYBURTON F. LATHAM JR.

4ATTORNEY LP. l y f ,.Illhh ikxuufl i All I:O man United States Patent O 3,669,628 BURNER AND FEEDSTOCK INJECTION ASSEM- BLY FOR CARBON BLACK REACTOR Burton F. Latham, Jr., Houston, and William B. Crull,

Dumas, Tex., assignors to Continental Carbon Company, Houston, Tex.

Filed July 31, 1970, Ser. No. 59,961 Int. Cl. C01b 31 00 U.S. Cl. 23-259.5 10 Claims ABSTRACT OF THE DISCLOSURE A burner and feedstock injection assembly for a carbon black reactor having three concentric pipes:

a center pipe for feedstock;

a second pipe, surrounding the center pipe;

a third pipe, surrounding the second pipe;

and a plurality (preferably three) of 'fuel-oil pipes disdosed within the annulus between the second and third plpes;

the ends of each of these fuel-oil pipes being equipped with a spray nozzle inclined at an angle with respect to the axis of the center pipe. These fuel-oil pipes are for the introduction of combustion fuel into the reactor. preferably, the assembly also includes a substantially cone-shaped iiameholder device mounted concentrically about the third pipe at the end thereof, such cone flaring outwardly toward the interior of the reactor, such cone being comprised of a plurality of vanes or louvers each of which is twisted at the outer ends thereof.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to the production of carbon black by the injection of a suitable hydrocarbon feedstock into an elongate reactor or combustion chamber containing high-temperature llames and gases, and more particularly to a burner and feedstock injection assembly for burning a normally liquid hydrocarbon as fuel to provide the heat necessary for the pyrolysis of the feedstock to form carbon black. Such assembly also includes means for supplying the feedstock to the reactor.

In many instances gas is used as a fuel to the burner; however, in situations where gas is not available, or is not available at an economical price, it is desirable to have a burner which is designed for the use of a normally liquid hydrocarbon fuel. The main object of this invention is to provide a burner which will operate satisfactorily on a normally liquid fuel rather than gas.

Description of the prior art Applicants do not claim that oil (rather than gas) burners for carbon black reactors are novel per se. The following patents disclose specific fuel-oil burner injection systems designed for specific carbon black reactors: 3,003,854; 3,060,003; 3,290,120; and 3,501,274. U.S. Pat. No. 3,443,761 discloses certain of the features of the present invention; however, it can readily be seen that the assembly of that patent is different and is suitable only for use with a gaseous fuel.

SUMMARY OF THE INVENTION This invention is a burner and feedstock injection assembly for an elongate substantially tubular carbon black reactor comprising:

a center pipe for introduction of feedstock into the reactor, one end of said pipe terminating within the reactor and being equipped with a spray nozzle;

a second pipe, concentrically disposed about the center ICC pipe, one end of the second pipe terminating approximately ilush with the end of the center pipe within the reactor;

a third pipe, concentrically disposed about the second pipe, one end of the third pipe terminating within the reactor at a point upstream of the end of the center P1116;

a plurality of fuel-oil pipes disposed within the annulus between the second and third pipes and axially parallel to said pipes, said fuel-oil pipes terminating at a point within the reactor downstream of the end of the third pipe but upstream of the end of the center pipe, the ends of said fuel-oil pipes being connected with a plurality of spray nozzles each of which is inclined at an angle of about 15 45 from the axis of the center Plpe;

means for. supplying carbon black feedstock to the center pipe;

means for supplying cooling medium to the annulus between the first and second pipes;

means for supplying a normally liquid hydrocarbon fuel to the fuel-oil pipes;

means for introducing a stream of process air into said reactor; and

means for directing said stream of process air downstream along the outside of the third pipe.

Preferably, the assembly also includes a ilameholder or air distribution device comprising a substantially coneshaped device mounted concentrically about the third pipe at the end of said third pipe, said cone flaring outwardly toward the interior of the reactor at an angle of about 5-30 (preferably 10-25) from the vertical, said device being comprised of a plurality of vanes or louvers each twisted at the outer end thereof to an angle of about 10-25 Desirably, the assembly also includes means for supplying air to the annulus between the second and third pipes, together with an annular passageway between the outer circumference of the second pipe and the nozzle ends of the fuel-oil pipes connecting such annulus with the interior portion of the reactor.

BRIEF DESCRIPTION 0F THE DRAWING FIG. l is an elevational view partly in section illustrating the preferred embodiment of the burner and feedstock injection assembly;

FIG. 2 is a view taken along the line 2--2 of FIG. l;

FIG. 3 is a longitudinal view, partly in section, of one form of a suitable carbon black reactor including the preferred burner and feedstock injection assembly;

FIG. 4 is a longitudinal view, partly in section, showing another suitable form of carbon black reactor including the preferred burner and feedstock injection assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. l, burner and feedstock injection assembly 1 will first be described. The feedstock line is center pipe 2 which is slideably mounted within axial pipe 3 and sealed therefrom by means of suitable packing glands included within closure member 4. Center pipe 2 is provided with guides (as shown) for proper positioning within axial pipe 3. The downstream end of center pipe 2 is provided with a suitable spray nozzle 5, which can be any conventional commercially available nozzle, preferably of the hollow cone type.

The upstream end of axial pipe 3 is provided with a T-connection 6 for introduction of air into the annulus between the center pipe and the axial pipe.

The tip of nozzle 5 terminates in approximate ush relationship with axial pipe 3.

Axial pipe 3 is slideably mounted within the assembly 1 by means of closure member 7 equipped with packing glands as shown.

As suggested above, the ow of air through axial pipe tread grades of black; whereas, FIG. 4 is designed for the production of carcass grades.

Referring to FIG. 3, preheated air passes through annulus 23 formed by shell 24 and inner tube 25. Portions in order to adjust the properties (particularly modulus and structure) of the carbon black.

Although the specic design of the elongate tubular carbon black ,reactor is not critical to the practice of this invention, we prefer the design shown in FIGS. 3 and 4.

FIG. 3 is particularly suitable for the production of 3 serves to keep the nozzle 5 from becoming overheated. 5 of the air enter the interior of the reactor through louvers It is within the scope of this invention to surround pipe 3 26 in combustion-aid device 27. A portion of the combuswith a water-cooled jacket so that the burner assembly tion air also enters the reactor through annular opening can be cooled with water rather than air. A specific water- 28. The downstream end of the reactor can be of any suitcooled jacket assembly is disclosed in U.S. patent appliable design as for example FIG. 1 of U.S. Pat. No. 3,256,- cation Ser. No. 59,962 tiled July 31, 1970 and now aban- 065 O1 FIG- 1 Of U-S. Pat. NO- 3,256,065-

doned in favor of continuation-in-part application Ser. No. The preheated COmbUStOIl ail enters the IeaCtOI' 0f 1.84934fi1ed Sept, 29, 1971 FIG. 4 as shown. The downstream end of the reactor of Tubular member or pipe 8, which is mounted concen- FIG. 4 can be of any eOllVeDieDt design 3S fel' example trically about the axial pipe 3, is preferably equipped near FIG. 1 of U.S. Pat.,No. 2,976,127. the upstream end with expansion joint 9, which in turn is We normally atomize the liquid hydrocarbon fuel outsecured to annular chamber 10. Annular chamber 10 in Side 0f the reactor, Pri0 1' t0 Supplying Such fuel oil t0 turn is equipped with pipe 11 for introduction of fuel oil Pipe 11, With any CODVement ealfylng Huld Sueh aS Steam, in a manner to be described below, air, natural gas, hydrogen or the like. In addition, the fuelr Communicating with hamber 10 are a plurality (pref. droplets, suspended in the carrier fluid, are further atomerably three) ef fuel-611 pipes 12, one of which is Shown ized at the nozzlein FIG. 1. These fuel-oil pipes v12 are mounted within the EXAMPLES ennuh@ between the axlal'a-r P1Pe 3 and the Surrounding The table below lists typical operating conditions which j Outer P1Pe 8 of the assembly 1' have been satisfactorily employed for commercial opera- The downstream ends of Plpes 12 are Secured to the tions while utilizing the burner and feedstock injection assembly by means 0f annular member 13- Amulaf mem 25 assembly of FIGS. 1 and 2. The normally-liquid fuel used bel 14, Which iS Seel-1red t0 annulal member 13, has a was naphtha of a gravity of about 75 API. The feedstock plurality of holes drilled at an angle through said mernwas a highly-aromatic tar from a thermal cracking unit ber, one hole for each of the fuel-oil pipes 12. Each hole having a gravity of about -1.5 API.

TABLE Run number 1 2 3 4 5 6 7 8 Grade ofearbon black--. HAF HAF-Hs HAF-Ls ISAF ISAF-Hs ISAF-Ls SRF FEF Reactor, figure 3 3 3 3 3 4 4 Combustion air rate,s.c.f.h. 160,000 150,000 150,000 150,000 180,000 180, 000 120,000 150,000 Air preheat temperature, F- 672 550 672 599 394 613 625 Naphtha new rate 11), GPH 86. 5 09. 7 72.` 0 00. 7 88 89 76. 7 72. 5 Axial air rate, s.c.f.h 10,000 10,000 10,000 10, 000 10, 000 10, 000 10,000 10,000 Feedstock oil rate, GPH (average) 286 233 267 191 248 221 263 266 is equipped with a spray nozzle 15 (preferably a Hat-spray While we have thus described the preferred embodinozzle) inclined at an angle of about 15-45 (preferably 40 ments of the present invention, many variations will be 15-25) from the axis of the center pipe. It would be suggested to those skilled in the art. The foregoing descripobvious to those skilled in the art that annular members tion and examples should therefore not be considered 13 and 14 could be replaced by an annular member conlimitative; and all such variations and modifications as are taining an annular groove so that the number of fuel-oil in accord with the principles described are meant to fall pipes 12 could be less than the number of nozzle 15. 4 within the scope of the appended claims.

Preferably, the assembly includes a substantially coneo Having thus described our invention, we claim: shaped device 16 mounted concentrically about the end 1. In combination with an elongate, substantially tubuof pipe 8, the cone of which flares outwardly toward the lar carbon black reactor, a burner and feedstock injection interior of the reactor 22 at an angle of about 530 assembly concentrically disposed within said reactor at (preferably 10-15) from the vertical, said device being ,l the upstream end thereof, said assembly comprising: comprised of a plurality of vanes or louvers each of which o a center pipe for introduction of feedstock into the is twisted at the outer end to an angle of about 10-25. reactor, one end of said pipe terminating within the This device 16 functions as a llameholder or air distribureactor and being equipped with a spray nozzle; tion vane and is advantageous for at least two reasons: a second pipe, concentrically disposed about the center (1) it serves to control at least a portion of the combustion 55 pipe, one end of the second pipe terminating approxiair flowing downstream `along the outer circumference of mately flush with the end of the center pipe within the pipe 8 by preventing such air from blowing the flame to a reactor;

- position too close to axial pipe 3 and the feedstock spray; a third pipe, concentrically disposed about the second (2) the twisted vanes or louvers impart a swirling motion pipe, one end of the third pipe terminating within the to the air, thus helping to disperse the fuel more evenly 60 reactor at a point upstream of the end of the center about the combustion area. pipe;

Desirably, the -assembly also includes an air inlet 18 a substantially frusta-conical device mounted concenand an annular passageway 19 so that a stream of air can trically to the outer circumference of the third pipe be swept through annulus 20 and annulus 19 and then to at the downstream end of said third pipe, said cone the reactor, in order to help cool the spray nozzles 15. 6 :daring outwardly from said third pipe toward the FIGS. 3 and 4 show the preferable positioning of burner o interior of the reactor at an angle of about 5-30 and feedstock injection assembly 1 in the upstream end of from the vertical, said device being comprised of a an elongate tubular carbon black reactor 22. Preferably, plurality of vanes or louvers each twisted at the the assembly is slideably mounted in the reactor so that the outer end thereof t0 an angle of about 10-25 "g position of the assembly within the reactor can be varied a plurality of fuel-oil pipes disposed within the annulus between the second and third pipes and axially parallel to said pipes, said fuel-oil pipes terminating at a point within the reactor downstream of the end of the third pipe but upstream of the end of the center pipe, the ends of said fuel-oil pipes being connected with a plurality of fuel-spray nozzles each of which is inclined at an angle of about l45 from the axis of the center pipe;

means for supplying carbon black feedstock to the center pipe;

means for supply cooling medium to the annulus between the first and second pipes;

means for supplying a normally liquid hydrocarbon fuel to the fuel-oil pipes;

means for introducing a stream of process air into said reactor; and

means for directing said stream of process air downstream along the outside of the third pipe.

2.. The combination of claim 1 in which the fuel spray nozzles are aat spray nozzles.

3. The combination of claim 1 in which there are three fuel-spray nozzles spaced apart at about 120.

4. The combination of claim 2 in which there are three fuel-spray nozzles spaced apart at about 120.

5. The combination of claim 4 additionally including means for supplying air to the annulus between the second and third pipes; and an annular passageway, between the outer circumference of the second pipe and the nozzled ends of the fuel-oil pipes, connecting said annulus with the interior portion of the reactor.

6. 'I'he combination of claim 1 in which the frustoconical device flares outwardly at an angle of about 25 from the vertical and the spray nozzles are inclined at an angle of about -25.

7. The combination of claim 2 in which the frustoconical device ares outwardly at an angle of about l025 from vertical and the flat-spray nozzles are inclined at an angle of about 15-25.

8. The combination of claim 3 in which the frustoconical device llares outwardly at an angle of about 10-25 from the vertical and the Hat-spray nozzles are inclined at an angle of about 15 25.

9. The combination of claim 4 in which the frustoconical device dares outwardly at an angle of about 10-25 from the vertical and the Hat-spray nozzles are inclined at angle of about 15 25 10. The combination of claim 5 in which the frustoconical device ilares outwardly at an angle of about l025 from the vertical and the lHat-spray nozzles are inclined at an angle of about 1525.

References Cited UNITED STATES PATENTS 3,256,066 6/ 1966 Higgins 23-259.S 3,290,120 12/19'66 Wright et al. 23-259.5

JAMES H. TAYMAN, IR., Primary Examiner U.S. Cl. X.R.

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