System for using flue gas heat

Abstract

A system including a pyrolysis unit for pyrolyzing organic material to produce at least pyrolysis oil and coke, a regenerator unit to combust the coke and produce a regenerator flue gas, and a mixer connected to the regenerator unit to mix the regenerator flue gas with air to produce a cooled flue gas. The system may further include at least one heat exchanger connected to the mixer to extract heat from the cooled flue gas, and a conveyer belt in thermal communication with the at least one heat exchanger and operably connected to the pyrolysis unit. The conveyer belt conveys a organic material in need of drying past the at least one exchanger to produce organic material suitable for use as a feed to the pyrolysis unit.

What is claimed is: 
     
         1 . A system, comprising:
 a pyrolysis unit for pyrolyzing organic material to produce a composition comprising coke;   a regenerator unit to combust at least a portion of the coke and produce a regenerator flue gas;   a mixer connected to the regenerator unit to mix the regenerator flue gas with air to produce a cooled flue gas;   at least one heat exchanger connected to the mixer to extract heat from the cooled flue gas; and   a conveyer belt in thermal communication with the at least one heat exchanger and operably connected to the pyrolysis unit, wherein the conveyer belt conveys organic material in need of drying past the at least one heat exchanger to dry the organic material.   
     
     
         2 . The system of  1 , wherein the pyrolysis unit includes as a heat transfer media a particulate source of heat. 
     
     
         3 . The system of  claim 2 , wherein the regenerator unit is configured to recycle at least a portion of the heat transfer media to the pyrolysis unit. 
     
     
         4 . The system of  claim 1 , wherein the regenerator flue gas has a temperature of greater than about 1000° F. before it is mixed with the air. 
     
     
         5 . The system of  claim 1 , wherein the cooled flue gas has a temperature of about 700° F. or less after it is mixed with the air. 
     
     
         6 . The system of  claim 1 , wherein the air is ambient air. 
     
     
         7 . The system of  claim 1 , further comprising stainless steel transfer lines for transferring the flue gas from the regenerator unit to the mixer. 
     
     
         8 . The system of  claim 1 , further comprising carbon steel transfer lines for transferring the cooled flue gas from the mixer to the at least one heat exchanger. 
     
     
         9 . The system of  claim 1 , further comprising at least one fan for directing moist air away from the organic material being conveyed on the conveyer belt. 
     
     
         10 . The system of  claim 1 , wherein the organic material in need of drying has a moisture content of greater than about  10 % by weight or more when it enters the conveyor belt. 
     
     
         11 . The system of  claim 10  wherein the organic material has a moisture content of less than about 10% by weight after being conveyed past the at least one heat exchanger. 
     
     
         12 . A process for pyrolysis and drying of organic material, comprising:
 pyrolyzing organic material to generate coke;   combusting the coke in a regenerator to produce flue gas;   cooling flue gas from the regenerator by mixing the flue gas with air; and   channeling the cooled flue gas to a heat exchanger to assist in drying wet organic material.   
     
     
         13 . The process of  12 , wherein heat transfer media is used when pyrolyzing the organic material and is transferred to the regenerator with the coke, the heat transfer media being a particulate source of heat. 
     
     
         14 . The process of  13 , wherein the regenerator returns the heat transfer media to a pyrolysis unit for reuse in pyrolyzing additional organic material. 
     
     
         15 . The process of  14 , further comprising the step of feeding organic material that has been dried in the dryer into the pyrolysis unit. 
     
     
         16 . The process of  12 , wherein the flue gas initially has a temperature of at least about 1000° F. before cooling. 
     
     
         17 . The process of  12 , wherein the flue gas is cooled to about 700° F. or less. 
     
     
         18 . A system for pyrolyzing and drying biomass, comprising:
 a pyrolysis unit employing sand as a heat transfer medium, wherein the pyrolyzing unit pyrolyzes biomass to form a mixture comprising pyrolysis oil, coke, and heated sand, and wherein the unit has an outlet to transfer the coke and heated sand;   a regenerator operably connected to the outlet of the pyrolysis unit to receive the coke and heated sand, wherein the regenerator combusts the coke to a regenerator flue gas and transfers at least a portion of the sand back into the pyrolysis unit;   a mixer operably connected to the regenerator to receive the regenerator flue gas and mix the regenerator flue gas with ambient air to produce a cooled flue gas; and   at least one heat exchanger operably connected to the mixer to use the cooled flue gas to dry biomass in need of drying.   
     
     
         19 . The system of  claim 18 , wherein the mixer cools the regenerator flue gas to a temperature suitable for transport through carbon steel lines. 
     
     
         20 . The system of  claim 18 , further comprising a conveyor belt to convey the biomass in need of drying past the heat exchangers to dry the biomass to a moisture content of less than about 10%.