Apparatuses, systems, cooling augers, and methods for cooling biochar

Abstract

Apparatuses, systems, char cooling augers, and methods for cooling biochar are described. An example system may include a char cooling auger coupled to a gasifier. The char cooling auger including a receiving hopper and an outer tube. The receiving hopper configured to receive and hold biochar from the gasifier. The receiving hopper configured to feed the biochar to a screw conveyor. The screw conveyor configured to rotate to transport the biochar from a first end of the outer tube to an outlet port near a second end of the outer tube. A temperature of the outer tube is less than a temperature of the biochar such that the biochar is cooled as transported through the outer tube prior to collection of the biochar.

What is claimed is: 
     
         1 . A system, comprising:
 a char cooling auger coupled to a gasifier, the char cooling auger comprising a receiving hopper and an outer tube, the receiving hopper configured to receive and hold biochar from the gasifier, the receiving hopper configured to feed the biochar to a screw conveyor extending through the outer tube, the screw conveyor configured to transport the biochar from a first end of the outer tube to an outlet port near a second end of the outer tube, wherein a temperature of the outer tube is less than a temperature of the biochar such that the biochar is cooled as it is transported through the outer tube prior to collection of the biochar in a collection hopper.   
     
     
         2 . The system of  claim 1 , wherein the char cooling auger is coupled to the gasifier via a cyclone configured to separate syngas from the biochar. 
     
     
         3 . The system of  claim 1 , wherein the char cooling auger further comprises a rotation mechanism configured to rotate the screw conveyor to transport the biochar the outlet port. 
     
     
         4 . The system of  claim 3 , wherein the rotation mechanism comprises a motor . 
     
     
         5 . The system of  claim 4 , wherein the motor is directly connected to the screw conveyor via a drive belt or a drive chain. 
     
     
         6 . The system of  claim 3 , further comprising a control system configured to control a resident time of the biochar within the outer tube based on temperature data associated with the biochar by controlling the rotation mechanism. 
     
     
         7 . The system of  claim 6 , further comprising a thermocouple configured to provide the temperature data to the control system. 
     
     
         8 . The system of  claim 1 , further comprising airlocks coupled to the outlet port, the airlocks configured to hold pressure within the char cooling auger pressurized while allowing the biochar to exit the char cooling auger. 
     
     
         9 . The system of  claim 1 , wherein the collection hopper is coupled to the airlocks and configured to receive and hold the biochar provided at from the outlet port. 
     
     
         10 . The system of  claim 1 , further comprising a fan configured to blow air over the outer tube to enhance conduction of heat away from the outer tube. 
     
     
         11 . A system comprising:
 a gasifier configured to gasify biomass to provide syngas and biochar;   a hopper configured to collect and store the biochar; and   a char cooling auger configured to cool the biochar received from the gasifier prior to providing the biochar to the hopper.   
     
     
         12 . The system of  claim 11 , wherein the char cooling auger comprises a screw conveyor configured to transport the biochar within an outer tube. 
     
     
         13 . The system of  claim 12 , wherein the char cooling auger further comprises a rotation mechanism configured to rotate the screw conveyor. 
     
     
         14 . The system of  claim 12 , further comprising fins affixed to the outer tube and configured to conduct heat away from the outer tube. 
     
     
         15 . A method, comprising:
 receiving biochar from a gasifier, wherein the biochar is generated by gasifying organic feedstock;   transporting the biochar through a char cooling auger, wherein the biochar is cooled as it is transported through the char cooling auger; and   collecting and storing the biochar in a hopper after transporting the biochar through the char cooling auger.   
     
     
         16 . The method of  claim 15 , further comprising controlling a rotation speed of a center rod of a screw conveyor within the char cooling auger, wherein the screw conveyor includes flighting that is affixed to the center rod and is configured to transport the biochar. 
     
     
         17 . The method of  claim 16 , wherein controlling the rotation speed of the center rod within the char cooling auger is based on the temperature of the biochar at the outlet port. 
     
     
         18 . The method of  claim 16 , further comprising sensing the temperature of the biochar at the outlet port. 
     
     
         19 . The method of  claim 18 , further comprising slowing the rotation speed of the center rod responsive to the temperature of the biochar at the outlet port exceeding a threshold. 
     
     
         20 . The method of  claim 19 , wherein the threshold is an operational limit of the airlock.