Gas distributors for circulating fluidized bed reactors

Abstract

A distributor for a circulating dry scrubber reactor includes a venturi section with a venturi section wall extending from a venturi section inlet to a venturi section outlet along a longitudinal axis, with the venturi section inlet connected to an inlet plenum and the venturi section outlet connected to a circulating dry scrubber reactor. A hub is mounted within the venturi section wall with an annular converging-diverging flow path defined between the venturi section wall and the hub for distribution of gas flow from the venturi section outlet into a circulating dry scrubber reactor space and for maintaining stable bed fluidization in a CDS system at a comparatively low system pressure loss.

1 . A distributor for a circulating dry scrubber reactor comprising:
 a venturi section including a venturi section wall extending from a venturi section inlet to a venturi section outlet along a longitudinal axis, wherein the venturi section outlet is configured and adapted to be connected to a circulating dry scrubber reactor;   a hub mounted within the venturi section wall with an annular converging-diverging flow path defined between the venturi section wall and the hub for distribution of gas flow from the venturi section outlet into a circulating dry scrubber reactor space and for maintaining stable bed fluidization;   an inlet plenum connected upstream of the venturi section inlet to supply a flow of gas to the annular converging-diverging flow path, wherein the inlet plenum includes an elbow section; and   at least one ladder vane mounted inside the elbow section, wherein the at least one ladder vane and the elbow section are configured to turn a flow of gas from the inlet plenum toward the venturi section inlet.   
     
     
         2 . (canceled) 
     
     
         3 . A distributor as recited in  claim 1 , wherein at least one portion of the venturi section wall defines a frustoconical wall and the frustoconical wall tapers inward toward the hub. 
     
     
         4 . A distributor as recited in  claim 3 , wherein the frustoconical wall and a corresponding part of the hub define a converging area of the converging-diverging flow path. 
     
     
         5 . A distributor as recited in  claim 3 , wherein the frustoconical wall and a corresponding part of the hub define a diverging area of the converging-diverging flow path. 
     
     
         6 . A distributor as recited in  claim 1 , wherein a portion of the venturi section wall defines a cylindrical wall. 
     
     
         7 . A distributor as recited in  claim 6 , wherein the cylindrical wall and a corresponding part of the hub define a diverging area of the converging-diverging flow path. 
     
     
         8 . A distributor as recited in  claim 1 , wherein the hub includes an inlet section that defines a converging portion of the flow path in a direction from the venturi section inlet to the venturi section outlet, and wherein the hub includes an outlet section that defines a diverging portion of the flow path in the direction from the venturi section inlet to the venturi section outlet. 
     
     
         9 . A distributor as recited in  claim 8 , wherein the inlet section of the hub is substantially conical. 
     
     
         10 . A distributor as recited in  claim 9 , wherein the inlet section cone has a conical angle of about 60° to about 90°. 
     
     
         11 . A distributor as recited in  claim 8 , wherein the outlet section of the hub is substantially conical. 
     
     
         12 . A distributor as recited in  claim 11 , wherein the outlet section cone has a conical angle of about 40° to about 90°. 
     
     
         13 . A distributor as recited in  claim 8 , wherein the inlet section of the hub is substantially hemispherical. 
     
     
         14 . A distributor as recited in  claim 8 , wherein the outlet section of the hub is frustoconical. 
     
     
         15 . A distributor as recited in  claim 11 , wherein a tip portion of the outlet section cone defines a frustocone truncated about 7% to about 12% short of a full cone. 
     
     
         16 . A distributor as recited in  claim 14 , wherein a lifting ring is mounted to the truncated tip portion of the hub outlet section. 
     
     
         17 . A distributor as recited in  claim 8 , wherein the hub includes a cylindrical section connecting the inlet and outlet sections of the hub. 
     
     
         18 . A distributor as recited in  claim 8 , wherein the inlet section of the hub has a vertex with an axial position at or below the venturi section inlet of the venturi section wall relative to the longitudinal axis. 
     
     
         19 . A distributor as recited in  claim 8 , wherein the outlet section of the hub has a high axial point at a common axial position with the venturi section outlet of the venturi section wall relative to the longitudinal axis. 
     
     
         20 . A distributor as recited in  claim 1 , wherein the hub has a diameter of at least about 58% that of the venturi section wall. 
     
     
         21 . A distributor as recited in  claim 1 , wherein the hub has a diameter of about 40% to about 90% of that of the venturi section wall. 
     
     
         22 . A distributor as recited in  claim 1 , wherein the venturi section wall has a diameter and a length in an axial direction with respect to the longitudinal axis, wherein the length of the venturi section wall is at least about 70% to about 140% as long as the diameter of the cylindrical wall. 
     
     
         23 . A distributor as recited in  claim 1 , further comprising a plurality of supports, each mounting the hub to the venturi section wall. 
     
     
         24 . A distributor as recited in  claim 1 , further comprising at least one support at an end of the hub, mounting the hub to the venturi section wall. 
     
     
         25 . A circulating dry scrubber comprising:
 a circulating dry scrubber reactor with an inlet for introducing flue gas and a reactor space for circulating particles for treating flue gas within the reactor space; and   a distributor as recited in  claim 1 , wherein the venturi section outlet of the distributor is in fluid communication with the inlet of the reactor to supply flue gas thereto.   
     
     
         26 . A distributor for a circulating dry scrubber reactor comprising:
 a venturi section including a venturi section wall extending from a venturi section inlet to a venturi section outlet along a longitudinal axis, wherein the venturi section outlet is configured and adapted to be connected to a circulating dry scrubber reactor;   a hub mounted within the venturi section wall with an annular converging-diverging flow path defined between the venturi section wall and the hub for distribution of gas flow from the venturi section outlet into a circulating dry scrubber reactor space and for maintaining stable bed fluidization, wherein the hub includes an outlet section that defines a diverging portion of the flow path in the direction from the venturi section inlet to the venturi section outlet, wherein at least a portion of the outlet section of the hub is below the venturi section outlet of the venturi section wall relative to the longitudinal axis;   an inlet plenum connected upstream of the venturi section inlet to supply a flow of gas to the annular converging-diverging flow path, wherein the inlet plenum includes an elbow section; and   at least one ladder vane mounted inside the elbow section, wherein the at least one ladder vane and the elbow section are configured to turn a flow of gas from the inlet plenum toward the venturi section inlet.