The present invention is directed to the upgrading of heavy
petroleum oils of high
viscosity and low
API gravity that are typically not suitable for pipelining without the use of diluents. It utilizes a short
residence-time pyrolytic reactor operating under conditions that result in a rapid pyrolytic
distillation with
coke formation. Both physical and chemical changes taking place lead to an overall molecular weight reduction in the
liquid product and rejection of certain components with the byproduct
coke. The
liquid product is upgraded primarily because of its substantially
reduced viscosity, increased
API gravity, and the content of middle and light distillate fractions. While maximizing the overall liquid yield, the improvements in
viscosity and
API gravity can render the
liquid product suitable for pipelining without the use of diluents. This invention particularly relates to reducing
sulfur emissions during the
combustion of byproduct
coke (or coke and gas), to reducing the
total acid number (TAN) of the liquid product, and to reducing the
hydrogen sulfide content of one, or more than one component of the product
stream. The method comprises introducing a particulate
heat carrier into an up-flow reactor, introducing the feedstock at a location above the entry of the particulate
heat carrier, allowing the heavy
hydrocarbon feedstock to interact with the
heat carrier for a short time, separating the vapors of the product
stream from the particulate heat carrier and liquid and byproduct
solid matter, regenerating the particulate heat carrier in the presence of the
calcium compound, and collecting a gaseous and liquid product from the product
stream.