Atmospheric fluidized bed combustor

Claim 1

A fluidized bed combustion system comprising: means defining a primary combustion region; a movable, perforate support in said combustion region for supporting fuel particles; first fuel feed means adjacent to said defining means for feeding relatively large fuel particles toward and onto the support; second fuel feed means spaced above the first fuel feed means for feeding relatively small fuel particles toward said support; means below the support for creating a flow of air upwardly through the support and into a zone above the support, whereby some of the fuel particles will be fluidized to present a fluidized bed within the combustion region; means above the primary combustion region for forming a secondary combustion region whereby fuel fines directed upwardly with the combustion gases from the primary combustion region can be burned; means at a location spaced above the secondary combustion region for scrubbing the combustion gases therefrom to remove the sulfur content, said scrubbing means including means for directing sorbent particles into the path of travel of the combustion gases flowing from said secondary combustion region; and means downstream of the scrubbing means for placing the combustion gases in heat exchange relationship to a fluid.

Claim 8

A method of energy recovery from fuel particles comprising: directing relatively large fuel particles from a first location toward and onto a movable, perforate support in a first combustion region; feeding relatively small fuel particles from a second location above the first location toward the support for combustion in said combustion region; directing fluidizing air through, and above the support to fluidize at least some of the particles above the support; burning the particles as the particles on the support are moved laterally and as the particles above the support are fluidized, whereby combustion gases will be generated in the first combustion region; directing the combustion gases away from the first combustion region; burning the fuel fines in the combustion gases at a second combustion region spaced above the first combustion region; feeding sorbent particles into the combustion gases at a location spaced above the second combustion region to scrub and remove sulfur from the combustion gases; and moving the scrubbed combustion gases into heat exchange relationship to a fluid for heating the fluid.

Claim 9

A method of energy recovery from fuel particles comprising: directing relatively large fuel particles from a first location toward and onto a movable, perforate support in a first combustion region; feeding relatively small fuel particles from a second location above the first location toward the support for combustion in said combustion region; directing fluidizing air through, and above the support to fluidize at least some of the particles above the support; burning the particles as the particles on the support are moved laterally and as the particles above the support are fluidized, whereby combustion gases will be generated in the first combustion region; directing the combustion gases away from the first combustion region; burning the fuel fines in the combustion gases at a second combustion region spaced above the first combustion region; feeding sorbent particles into the combustion gases at a location spaced above the second combustion region to scrub and remove sulfur from the combustion gases; and moving the scrubbed combustion gases into heat exchange relationship to a fluid for heating the fluid.