Arc heater apparatus for producing acetylene from heavy hydrocarbons

Arc heater apparatus for producing acetylene from heavy hydrocarbon, comprising walls forming a plenum chamber having a substantially vertical axis, a plurality of arc heaters at the upper end of the chamber and including a pair of axially spaced substantially cylindrical electrodes forming a narrow gap therebetween and adapted to be connected to a source of potential to produce an arc therebetween, the electrodes defining an arc chamber that communicates with the plenum chamber, the axes of the arc chambers of the arc heaters being inclined upwardly from the vertical axis, gas inlet means communicating with the gap for introducing a non-conductive reducing gas into the arc chamber, the arc heaters being productive of an arc heated plasma gas to effect a downstream reaction zone in a plenum chamber, second inlet means upstream of the arc heaters for introducing heavy hydrocarbon material into the reaction zone, and the walls forming the plenum chamber diverging downwardly and outwardly from the location of the arc heaters so that deposits of solid reaction products on the walls are minimized.