PYROLYSIS FURNACE PROVIDED WITH U-SHAPED INTERNAL-RIBBING COIL Russian patent published in 2003 - IPC

FIELD: chemical engineering. SUBSTANCE: heater for heating process flowing medium comprises reaction chamber with, disposed therein, two-pass tubular sections containing at least one inlet branch connected to at least one outlet branch; bent tubular member connecting inlet branch with outlet branch; means for feeding process flowing medium into inlet branch; heat-radiation means to affect outside surface of tubular sections; outlet means for cooling and collecting flowing medium. Each tubular section is provided with internal ribs. Olefin production process includes preliminarily heating hydrocarbon feedstock, feeding the latter into a multitude of radiation coils, heating radiation coils by a multitude of burners, collecting and cooling cracked hydrocarbon feedstock, and recovering at least one olefin from the latter. Each radiation coil has at least one inlet branch connected to at least one outlet branch to pass flowing medium stream and bent tubular member connecting inlet branch with outlet branch, which is provided with internal ribs in all tubular sections. EFFECT: increased heat emissions from internal tube surface, decreased coking, lowered temperature of tube metal, and increased ethylene production selectivity. 27 cl, 3 dwg, 2 tbl