GB1262104A - Method and apparatus for heating gases to high temperatures - Google Patents

Abstract

1,262,104. Electric heating apparatus; discharges in gases. NORTHERN NATURAL GAS CO. 20 Feb., 1969 [10 April, 1968], No. 9138/69. Addition to 1,141,741. Heading H5H. The apparatus of parent Specification is modified by introducing into one of the electrical discharge zones a hydrocarbon pyrolysis feed stock so as to form intermediate products, which are rapidly quenched to form the required product, e.g. acetylene from methane. Other products mentioned are vinyl chloride, fluorocarbons or other halocarbons, the appropriate elemental gases being introduced with the hydrocarbon feed stock. The methane is injected into the second stage of the burner, Fig. 8, which comprises a heat resistant tube 70 extending between a pilot burner tip 20 and an electrode assembly 72, the methane entering via an opening 37 and into a metal tube electrode 50 where it is ignited by the pilot flame and passes through the discharge between electrodes 50, 72, and on through the uniformly distributed discharge in the third stage zone between cooled electrode assembly 72 and an electrode 114, the third stage comprising a cooled tube 108. A gas sampling probe 156 is provided at the exit from cooled electrode 114. In an alternative embodiment, Fig. 9 (not shown), the methane is injected into a fourth stage unit immediately following the first three stages of the burner 7 with a gas injection manifold 162 at the upstream end of the fourth stage providing secondary injection of the fuel for pyrolysis. The preferred embodiment, Fig. 10, provides for the injection of methane into the third stage of the reactor such that mixing of the pyrolysis fuel and electrical heating occur in the same isothermal reaction zone. The electrode assembly 72 is replaced by a modified electrode and sheath injection manifold 180, providing an annular gas injection port giving matching between the velocity of the injection gas and the combustion gas exiting from tube 70. The methane is injected via an inlet 184, (see also Figs. 11, 12, not shown), into the cooled manifold 180, and provides a cool sheath of injection gas along the walls of third stage tube 108.