Patent GB-1304390-A (GB)
IPC: C09C1/50
Filed: 1970-09-17
Abstract: 1304390 Carbon black CONTINENTAL CARBON CO 17 Sept 1970 [2 Oct 1969] 44518/70 Heading C1A A carbon black furnace comprises (a) an elongate housing having a first cylindrical section 48 at its upstream end with an air input conduit 52 extending into it, (b) a centrally apertured end-plate 58 enclosing the upstream end of the first housing; (c) a cylindrical annular baffle 72, coaxially mounted within section 48, extending upstream from the downstream end of the section, with its upstream end spaced from the end-plate 58 thereby establishing an annular zone between the first housing and the baffle; (d) a centrally apertured diffusion plate 62 having a series of perforations 66, 70, about the central aperture 64, coaxially mounted at the downstream end of the first housing section; (e) a second housing section 20, coaxialy aligned with first section 48, said second section having a refractory lining 24 of uniform inner diameter substantially equal to that of baffle 72, (f) a burner and feedstock injection assembly 78, mounted axially to the end plate, and extending through the central aperture thereof, the first housing section, the central aperture of the diffusion plate and into the second housing section; (g) a third housing section 21 coaxially aligned with the first section and having a refractory lining, 25, of uniform inner diameter, substantially greater than that of the lining 24 of the second section, said third housing 21 having a length greater than its diameter, (h) a tangential port 30 extending through said third section and lining at each of at least one point intermediate of the ends of the third section; (i) a tunnel burner means 44 communicating with the tangential port; (j) a fourth housing section 35 horizontally aligned with the bottom edge of the third housing section having a refractory lining of a diameter substantially the same as that of the lining of the second section, (k) a closure plate 27 affixed so as to join said third and fourth sections, plate 27 having a refractory lining 29 and being adapted to compensate for the difference in diameter between section 3 and 4, (1) a quench means 26 extending through the fourth section and through the refractory lining. Preferably the axial length of the first housing is less than its diameter, and the axial length of the second housing is less than the diameter of that section. The inner diameter, of the lining 25 of the third section is preferably substantially equal to the outer diameter of the second housing section. Preferably there are two tangential ports 30 spaced equidistantly about the circumference of the third housing section and in the same plane perpendicular to the axis of the furnace. This pair of ports may desirably be situated adjacent the upstream end of the second section. In another embodiment, a plurality of ports are utilized, spaced equidistantly around the circumference of the third housing and arranged in at least planes perpendicular to the axis of the furnace. Carbon black may be produced using the above furnace as follows:-introducing a fuel into the combustion zone 14 of the furnace, introducing a free oxygen containing gas, e.g. air, radially into the annular space 76 so as to flow about the cylindrical baffle 72, through the interior of the baffle, then through the plate 62 so as to flow longitudinally into the combustion zone and mix with the fuel; introducing the hydrocarbon feedstock axially into the zone into which the products of the combustion of fuel and air are introduced, passing the carbon black and byproducts so formed into a subsequent zone 16 at reduced flow velocity, this zone having a length greater than its diameter, and introducing additional fuel and a stoichiometric excess of free oxygen containing gas via tunnel burners 44 and passing the resulting combustion products with excess of air into the zone 16 via ports 30, completing the reaction, quenching and recovering the product.