Image Number 5 for United States Patent #4349432.
Process and apparatus for pyrolysis of a heavy hydrocarbon feedstock in which the feedstock is counter-currently contacted with a hot hydrogenating gas stream flowing spirally from the periphery of a substantially circular reactor (1). The hydrocarbon feedstock is injected through an inlet (4) located toward the center of reactor (1). The hot hydrogenating gas is preferably formed by combustion, using a steam-oxygen mixture injected through inlet (2), of carbonaceous by-products from the pyrolysis. Product is removed centrally through outlet (3).