Multi-stage circulating fluidized bed syngas cooling

A multi-stage syngas cooler system comprising:

• a dense fluid bed with a cooling system in communication with an inlet syngas stream;
• and
• internally circulating fluidized bed coolers in series;
• wherein each internally circulating fluidized bed cooler comprises:
• a riser configured to mix syngas with solids from a circulating bed of solids;
• a disengagement section configured to disengage at least a portion of the syngas from at least a portion of the circulating bed of solids;
• an annular space defined exterior the riser configured to enable at least a portion of the circulating bed of solids to flow down from the disengagement section;
• and
• a cone-shaped divider comprising cooling coils with openings configured so at least a portion of the syngas passes through and provides aeration for at least a portion of the down flowing circulating bed of solids in the annular space, the cone-shaped divider further configured to:
• facilitate circulation of at least a portion of the circulating bed of solids;
• and
• serve as a partition between successive internally circulating fluidized bed coolers;
• wherein the syngas is successively cooled, first in the dense fluid bed, and then in each of the internally circulating fluidized bed coolers;
• wherein the last of the internally circulating fluidized bed coolers comprises a system-cooled syngas outlet configured through which a system-cooled syngas stream exits the last of the internally circulating fluidized bed coolers;
• and
• wherein the system is configured such that the temperature of the system-cooled syngas outlet stream is at least 500° C. cooler than the temperature of inlet syngas stream.