Fluid injection nozzle for fluid bed reactors

摘要

The liquid feed nozzle assemblies for a circulating fluid bed reactor comprise (i) a throttle body premixer to combine liquid feed with atomization steam upstream of a nozzle body to form a liquid feed/steam mixture comprising liquid feed droplets; (ii) a conduit connected to the venturi premixer and to a discharge nozzle body to convey a flow of the liquid/steam mixture created by the premixer to the nozzle body; (iii) a discharge nozzle connected to the flow conduit to shear the liquid feed/steam mixture to create liquid feed droplets of reduced size and (iv) a disperser at the outlet of the discharge nozzle to provide a spray jet of liquid feed having an increased surface area relative to a cylindrical jet. The nozzle assembles are particularly useful in fluid coking units using heavy oil feeds such a tar sands bitumen.

主权项

1. A circulating fluid bed reactor having a reactor wall of circular cross section about a vertical axis, a lower inlet for fluidizing gas and feed injection nozzle assemblies for a liquid heavy oil feed and atomization steam above the lower fluidizing gas inlet and around the reactor wall, the nozzle assemblies each extending through the reactor wall into the reactor with a discharge nozzle orifice within the reactor and an inlet for the liquid heavy oil feed at the end remote from the discharge nozzle orifice; each feed injection nozzle assembly comprising:
a premixer section to combine the liquid heavy oil feed with the atomization steam to form a liquid feed/steam mixture comprising liquid feed droplets, the premixer section comprising a throttle constriction in a flow conduit defining a throat and a plurality of radial steam inlet ports located around the throat; a flow conduit section following and connected to the premixer section extending from the premixer section to a discharge nozzle, to convey a flow of the liquid/steam mixture created by the premixer to the discharge nozzle, the flow conduit including a flow conditioner of reduced cross-sectional flow area between the premixer section and the discharge nozzle and comprising successive convergence and divergence zones to reduce the size of the liquid feed droplets in the liquid feed/steam mixture from the premixer; a discharge nozzle having a convergent entry following and connected to the flow conduit section to shear the liquid feed/steam mixture and create liquid feed droplets of reduced size within the discharge nozzle, and a divergent multilobe disperser at the outlet of the discharge nozzle to generate a correspondingly shaped liquid jet plume having an increased surface area relative to a cylindrical jet.