GB652518A - Improvements in the manufacture of carbon black - Google Patents

Abstract

<PICT:0652518/III/1> <PICT:0652518/III/2> Carbon black is produced by blasting a combustible mixture of fuel gas and oxygen-containing gas into one end of an elongated, unobstructed, heat-insulated chamber, burning the combustible mixture to form a high velocity, highly turbulent stream of blast flame gases, injecting a stream of hydrocarbon gas into the resultant stream in an amount in excess of that required to consume any excess oxygen and in a direction concurrent with and substantially parallel to the direction of flow of the flame gases, continuing the highly turbulent flow of the gas mixture through the chamber at a temperature sufficiently high to decompose the hydrocarbon, cooling and collecting the carbon formed. Methane with at least 10 per cent air is blasted from burner assembly 2, Fig. 2, into reactor 1 at 1900-2900 DEG F. and methane, possibly enriched with higher hydrocarbons to more than 1200 B.Th.U. per cubic foot, which may be preheated to 500 DEG F. is injected into the reactor through tubes 17. The resultant gases flow, through the blending chamber 3 and passageway 4 wherein they are quenched by water sprays 11, to precooler 5, whence they pass to conventional cooling and collecting means. The contact time between injection and first quenching should be 1/2 -1 sec. In the burner assembly 2, Fig. 3, methane under pressure is fed through pipe 24 and manifold 23 to jets 21 positioned behind burner ports 16 in refractory burner block 15. Air under pressure is fed from air chamber 27a through perforated metal plate 31 into windbox 19. The hydrocarbon passes through pipes 26 and manifolds 25 to refractory injection tubes 17 which are so arranged that each one is surrounded by burner ports 16. The manifolds 23, 25 may be longitudinally slidable to adjust the position of jets 21 and the protrusion of tubes 17. The fuel and air may alternatively be premixed and the blast may be oxidizing, neutral or reducing. Specification 402,322 is referred to.