Mobile Pelletizing System

Abstract

The present invention provides portable pelletizing systems for in situ processing of biomass material to pellets. Systems according to embodiments of the invention have a complete set of processing components and an engine for powering the processing components. The processing components are interconnected. Loading, unloading, and coordination of each of the processing components is automatically controlled through a controller. A heat exchange network is integrated with the engine and the processing components, wherein the heat exchange network transfers heat between the engine and the processing components. The system is self-contained and may be transported using a vehicle so that the system may receive biomass material of varying composition and moisture content at a point of origin. The complete set of processing components may include an input, a means for reducing the size of the biomass material, a blender, a dryer, a conditioner, a pellet mill, a cooler, and an output.

1 . A mobile biomass pelletizing system comprising:
 modules for reducing, blending, drying, conditioning, and pelletizing biomass;   one or more sensors for determining composition, moisture, and temperature information about the biomass contained in the modules during use;   a control system in operable communication with the modules and sensors for:
 receiving the composition, moisture, and temperature information; 
 adjusting operating parameters of one or more module and automatically moving the biomass between modules in response to the information received; 
   wherein the modules are disposed within a single, portable housing; and   wherein during use pellets having a density within a selected range are produced from multiple batches of biomass feedstock varying in composition and moisture content.   
     
     
         2 . The system of  claim 1 , wherein during use the pellets produced have a density varying no more than 10% and are produced from biomass feedstock varying more than 2-5 times in moisture content. 
     
     
         3 . The system of  claim 1 , wherein during use total energy consumption is less than 150 kWh/t for operating all modules. 
     
     
         4 . A system for in situ processing of biomass material to pellets, comprising:
 an input module for receiving biomass;   a reducer module for reducing particles size of the biomass;   a blender module for homogenizing the biomass;   a dryer module for removing moisture from the biomass;   a conditioner module for adding moisture to the biomass;   a pellet mill module for converting the biomass into pellets;   a cooler module for optionally cooling the biomass or the biomass pellets;   an output module for exporting the biomass pellets from the system;   an engine in operable communication with and for powering any one or more of the input, reducer, blender, dryer, conditioner, pellet mill, cooler, or output modules;   wherein each module and the engine are disposed within a single housing.   
     
     
         5 . The system of  claim 4 , further comprising a heat recycling module for recycling heat from at least one of the engine or cooler modules to at least one of the input, reducer, blender, dryer, conditioner, or pellet mill modules. 
     
     
         6 . The system of  claim 4 , further comprising a controller in operable communication with any one or more of the input, reducer, blender, dryer, conditioner, pellet mill, cooler, or output modules for automatically operating each module. 
     
     
         7 . The system of  claim 6 , wherein one or more modules are interconnected by a means for transporting the biomass material between modules, wherein loading, unloading, and coordination of each module is automatically controlled through a controller. 
     
     
         8 . The system of  claim 1 , wherein the system is capable of being transported as a unit using a vehicle so that the system may receive biomass material of varying composition and moisture content at a point of origin. 
     
     
         9 . The system of  claim 1 , wherein the reducer module is a grinder comprising a grinder assembly with one or more pairs of opposed cutting means operably connected to a grinding motor and wherein spacing between the cutting means may be increased according the load on the motor, so that spacing is increased with increased load on the grinding motor, and wherein one of the pairs of opposed cutting means is a pair of auger-style cutters or a pair of shearing plates. 
     
     
         10 . The system of  claim 1 , wherein the dryer module comprises individual dryers comprised of a vertical tower wherein feed enters through the top of the tower and exits at the bottom, and exhaust enters from the bottom and exits from the top. 
     
     
         11 . The system of  claim 10 , wherein the dryer module is interconnected with a heat exchange network. 
     
     
         12 . The system of  claim 1 , wherein the pellet mill module comprises:
 a die assembly comprising two opposed cylindrical dies that rotate in an inward direction from the die assembly;   an input for receiving biomass; and   a motor;   wherein each die is operably connected to the motor;   wherein the two opposed dies each comprise a die head comprising a plurality of die holes extending radially through its circumference; and   wherein the two die heads having a point of contact at their circumference wherein biomass is extruded into pellets through compression of the biomass though the die holes at the point of contact.   
     
     
         13 . The system of  claim 12 , wherein spacing between the two opposed die heads may be adjusted according to the load on the motor, so that spacing is increased with increased load on the motor by:
 adjusting one of the die head's center of rotation using a cantilever operably connected to a cam actuator; or   adjusting one of the die head's center of rotation using a ring gear.   
     
     
         14 . The system of  claim 13 , wherein each die head comprises a plurality of vents for removal of water during extrusion. 
     
     
         15 . The system of  claim 8 , wherein the vehicle is a truck or a trailer. 
     
     
         16 . The system of  claim 7 , wherein the controller is a microprocessor operating under the control of a computer program. 
     
     
         17 . A process for in situ conversion of biomass to pellets, comprising:
 a. Receiving biomass material;   b. Reducing the size of the biomass material after it has been received;   c. Blending the biomass material after it has been reduced in size;   d. Drying the biomass material after it has been blended;   e. Conditioning the biomass material after it has been dried;   f. Pelletizing the biomass material to pellets after it has been conditioned;   g. Cooling the pellets after they have been extruded; and   h. Offloading the pellets after they have been cooled.   
     
     
         18 . The process of  claim 17 , wherein the biomass is screened between drying and conditioning of the biomass. 
     
     
         19 . The process of  claim 17 , wherein the process is carried out within a transportable system. 
     
     
         20 . The process of  claim 17 , wherein steps in the process are powered by an engine and heat from the engine is transferred to one or more of steps a-e.