Abstract: A fluidized bed combustion system and method for combusting particulate fuel such as coal together with a sorbent material such as limestone to heat a pressurized liquid and generate saturated vapor, such as steam. The combustion system utilizes at least one concentric dual-sided riser-downcomer unit having a central riser passageway and a concentric outer downcomer passageway located above a dense phase fluidized bed in an enclosure module, the downcomer being configured for directing particulate solids back to the bed. The unit inner and outer passageway surfaces each include a heat exchange panel containing the pressurized liquid for absorbing heat from combustion of the fuel and generating the vapor such as pressurized steam. Primary air is provided below the fluidized bed, while secondary air is provided into the riser passageway.

Abstract: An improved flow distribution system for a catalytic reactor plenum chamber for a gas-liquid-solids ebullated bed reactor incudes a baffled nozzle device containing at least two baffle plates usually oriented substantially normal to the nozzle inlet flow direction for providing good mixing and uniform flow distribution of gas-liquid materials in the lower portion of the plenum, used in combination with distribution grid to effect a substantially uniform flow distribution of the gas/liquid mixture upwardly into the ebullated catalyst bed. A sparger can be provided in the plenum above the baffled flow distributor device for feeding additional gas-liquid mixture into the reactor. The flow distribution system provides a substantially uniform flow distribution of the gas-liquid mixture into the ebullated bed and thereby provides fouling-free operation of the reactor.

Abstract: An improved flow distribution system for a catalytic reactor plenum chamber for a gas-liquid-solids ebullated bed reactor including a downwardly directed conduit and a flow distributor device such as a baffled nozzle attached to the inner end of the conduit, said nozzle containing at least two substantially parallel baffle plates usually oriented substantially normal to the nozzle inlet flow direction for providing initially downward flow and good mixing and radial flow disperson of gas-liquid materials in the lower portion of the plenum. The initially downward flow is then deflected generally upwardly by the curved lower head of the reactor plenum chamber and passes uniformly upwardly through a flow distribution grid into the ebullated catalyst bed. A sparger can be provided in the plenum above the flow distributor device for feeding additional gas-liquid mixture into the reactor.