Abstract: A reaction chamber equipped with external heat exchanging coils for limiting the range of the reaction temperature, which must not go over 1200.degree. C nor below 900.degree. C, is supplied with hydrocarbon reagent and combustion-supporting reagent (air) in a way designed to enable a partial combustion reaction by which carbon black is formed to provide the main source of heat for maintaining the reaction temperature. At the entry end of the reaction chamber is a header providing a multiplicity of ante-chambers through which the reagents flow in a direction parallel to the axis of the reaction chamber while being heated up by heat from the reaction chamber. When a liquid reagent is used, it is atomized in the ante-chambers and vaporized and mixed with air in its passage through the ante-chambers. The air is preheated by a heat exchanger that cools the reaction products after a preliminary cooling by another heat exchanger.

Abstract: The hydrocarbon material to be decomposed and the combustion-supporting gas, such as air, are conditioned before admission to the reaction chamber to provide formation of carbon black under conditions highly controllable as to output product properties, particularly with reference to the hydrocarbon-air ratio. The air is conditioned by pre-heating in a heat exchanger, liquid hydrocarbon raw material is conditioned by pre-heating, pressurizing, pressure regulation, flow rate regulation and, finally, spray atomizing in ante-chambers distributed across the cross section of the combustion chamber and housed in a removable header on the intake side of the reaction chamber, whereas gaseous hydrocarbon raw material is conditioned for the process by control-mixing, pre-heating and diffusion in the aforesaid ante-chambers. A gas-fueled heater is provided for preliminary warming up of the reaction chamber to a temperature sufficiently high for partial combustion of the reagents.