Ultrapyrolytic heavy oil upgrading in an internally circulating aerated

Abstract

A process is described for ultrapyrolytic upgrading of a heavy hydrocarbon oil feedstock by contacting the feedstock in a confined riser vertical column with finely divided inert solid particles under ultrapyrolysis conditions, the riser forms part of an internally circulating aerated bed reactor with the bottom end of the riser being directly connected to an inlet nozzle feeding the heavy hydrocarbon oil feedstock and the upper end of the riser extending above an annular aerated bed of the finely divided solid particles surrounding the riser. The riser also includes a plurality of orifices in a lower region thereof flow connected to a lower region of the aerated bed for controlled delivery of the particles from the aerated bed into the riser. The novel feature comprises continuously feeding an atomized stream of the heavy hydrocarbon oil feedstock upwardly through the inlet nozzle into the riser, continuously feeding finely divided solid heat carrier particles from the annular aerated bed into the riser through the orifices, contacting the particles and atomized feed within the riser under ultrapyrolysis conditions, continuously maintaining a level of particles in the aerated bed such that there is a net positive pressure difference between the aerated bed and the riser at the level of the orifices whereby riser gases are prevented from escaping into the annular bed, continuously removing particles and product gas from the upper end of the riser, continuously recycling the removed particles into the aerated bed and continuously withdrawing product gas from the system.