GB822039A - Improvements in and relating to the pyrolysis of hydrocarbons and apparatus therefor - Google Patents

Abstract

<FORM:0822039/IV (a)/1> An apparatus for pyrolysing a fluid hydrocarbon stock, particularly for pyrolysing methane to give acetylene, comprises a combustion chamber communicating with mixing means for fuel and oxidant at one end and a constricted throat at the other, such throat connecting with a pyrolysis chamber which communicates at its other end with quenching means, and inlet means for the hydrocarbon stock comprising openings in the peripheral inner wall between the constricted throat and the pyrolysis chamber so that the hydrocarbon stock is injected directly into the flowing stream of combustion products. Preferably the throat section is adapted to introduce the products from the combustion chamber into the process chamber at a velocity greater than March number 0.5. Injector member 22 comprises an oxidant conduit 70 communicating with ports 72 arranged vertical to and around the conical face at the lower end. This conical face forms with conical walls 24 an annular conical passage 26 through which flows the fuel introduced through conduit 74. By suitably maintaining a pressure ratio across the ports 72 and the passage 26 of greater than 2 : 1 velocities at or near sonic are achieved. The mixed gases pass into the combustion chamber 32 constructed of refractory material 110 lines with metal ceramic material 114. After combustion the gases pass through the constricted throat section 34 also suitably composed of metal ceramic material into the process chamber 40 constructed of refractory material 112 and lined with a metal ceramic 116. At the entrance to the chamber near the throat section is positioned the hydrocarbon inlet fed by the conduit 60. If the hydrocarbon is liquid it passes as a fine spray into the chamber 40 with the high-velocity combustion products which are preferably travelling at or near sonic speed. The products are quenched, preferably within 4 milliseconds from the commencement of pyrolysis, by the introduction of a quenching fluid through the ports 50 fed by conduit 56. Water cooling conduits 80 and 88, 90 and 98, and 100 and 108 are also provided.