Pelletising of Fibrous Combustible Material at Variable Pressure and Variable Temperature

• US 20090064569A1
• Filed: 09/08/2008
• Published: 03/12/2009
• Est. Priority Date: 09/06/2007
• Status: Abandoned Application

• Current Assignee: Abhay Kumar Khater
• Original Assignee: Abhay Kumar Khater
• Inventors: Khater, Abhay Kumar
• Application Number:
  US12/206,686
• Publication Number:
  US 20090064569A1
• Time in Patent Office: Days
• US Class Current: 44/589
• CPC Class Codes: B30B 11/228 using pressing means, e.g. rollers moving over a perforated die plate
• CPC Class Codes: B30B 15/34 Heating or cooling presses or parts thereof
• CPC Class Codes: C10L 5/363 Pellets or granulates
• CPC Class Codes: C10L 5/44 on vegetable substances
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel

Abstract

Fibrous combustible material such as biomass or biomass refuse is coarse chopped, dried and then may optionally loaded, transported, and unloaded. The biomass is further processed to a desired size and bulk density. Low speed knife cutters are used for cutting the fiber instead of crushing. Fibrous combustible material having a moisture content of approximately 20% and a temperature of approximately 70-80° C. is extruded between rollers and a fixed flat die, and releases glutinous juices during extrusion which enable pellet formation while also producing a polished cover to the extruded pellet during simple air cooling. A low and variable speed of 2-3 meters per second between rollers and fixed flat die is used for pelletising fibrous biomass. A desired temperature of the fixed flat die is maintained by circulating hot or cold water.

Claims

1. A method of converting a fibrous combustible material at a variable pressure, said variable pressure which is optimally different for diverse fibrous combustible materials, and at a variable temperature, said variable temperature which is optimally different for diverse fibrous combustible materials, into pellets consisting essentially of said fibrous combustible material by pressing said diverse fibrous combustible material through a die, comprising the steps of:

selecting a first relative speed between a press wheel and said die from a plurality of different available relative speeds, said first relative speed which will extract sufficient glutinous juice from said fibrous combustible material to form pellets during said pressing of said fibrous combustible material through said die, said first relative speed which varies dependent upon a composition of said fibrous combustible material;

choosing a first relative temperature for said die from a plurality of different available relative temperatures, said first relative temperature which will form pellets during said pressing of said fibrous combustible material through said die, said first relative temperature which varies dependent upon said composition of said fibrous combustible material;

adjusting said variable pressure and said variable temperature responsive to characteristics of said fibrous combustible material to a pressure produced by said first relative speed and to said first relative temperature to successfully pelletise said fibrous combustible material; and

pressing said fibrous combustible material through said die at said adjusted variable pressure and said adjusted variable temperature.

2. The method of converting a fibrous combustible material at a variable pressure and at a variable temperature of claim 1, further comprising the step of milling said fibrous combustible material using a knife hammer mill to produce a dimensionally reduced fibrous combustible material prior to said pressing step.

3. The method of converting a fibrous combustible material at a variable pressure and at a variable temperature of claim 1, wherein said die comprises a fixed flat die.

4. The method of converting a fibrous combustible material at a variable pressure and at a variable temperature of claim 1, further comprising the step of chopping said fibrous combustible material using a field chipper cutter.

5. The method of converting a fibrous combustible material at a variable pressure and at a variable temperature of claim 1, further comprising the step of conditioning said fibrous combustible material using steam prior to said pressing step.

6. The method of converting a fibrous combustible material at a variable pressure and at a variable temperature of claim 1, wherein said adjusting occurs simultaneously with said pressing step.

7. The method of converting a fibrous combustible material at a variable pressure and at a variable temperature of claim 1, wherein said first relative speed between said press wheel and said extrusion die is in the range of two to three meters per second.

8. The method of converting a fibrous combustible material at a variable pressure and at a variable temperature of claim 3, further comprising the step of exchanging said fixed flat die with a second fixed flat die different from said fixed flat die in at least one of die hole length and die hole taper.

9. A method of collecting and converting fibrous combustible material into fuel pellets, comprising the steps of:

chopping said fibrous combustible material;

drying said fibrous combustible material;

grinding subsequent to said chopping and drying steps while preserving gelatinous material within said fibrous combustible material to yield a dimensionally reduced fibrous combustible material; and

extruding said dimensionally reduced fibrous combustible material between a press and a die at low speed to thereby exude gelatinous binding material from said dimensionally reduced fibrous combustible material.

10. The method of collecting and converting fibrous combustible material into fuel pellets of claim 9, wherein said chopping step further comprises chopping said fibrous combustible material with a field chipper cutter.

11. The method of collecting and converting fibrous combustible material into fuel pellets of claim 9, wherein said grinding step further comprises grinding said fibrous combustible material with a knife hammer mill.

12. The method of collecting and converting fibrous combustible material into fuel pellets of claim 9, wherein said die further comprises a fixed flat die.

13. The method of collecting and converting fibrous combustible material into fuel pellets of claim 12, wherein said press further comprises at least one rotary press wheel which rolls about a horizontal axis, said horizontal axis rotating about a vertical axis, said rotary press wheel in contact with said fixed flat die during said rolling about said horizontal axis and rotating about said vertical axis.

14. The method of collecting and converting fibrous combustible material into fuel pellets of claim 9, further comprising the steps of:

selecting a first relative speed between said press and said die from a plurality of different available relative speeds, said first relative speed which will extract sufficient glutinous juice from said fibrous combustible material to form pellets during said extruding of said fibrous combustible material through said die, said first relative speed which varies dependent upon a composition of said fibrous combustible material;

choosing a first relative temperature for said die from a plurality of different available relative temperatures, said first relative temperature which will form pellets during said extruding of said fibrous combustible material through said die, said first relative temperature which varies dependent upon a composition of said fibrous combustible material; and

adjusting said first relative speed and said variable temperature responsive to characteristics of said dimensionally reduced fibrous combustible material to a pressure produced by said first relative speed and to said first relative temperature to successfully pelletise said fibrous combustible material.

15. A fixed flat die extruder for pelletising fibrous combustible material at variable pressure and variable temperature, comprising:

an inlet receiving said fibrous combustible material into said fixed flat die extruder;

at least one press wheel traversing a fixed die;

a controlled and variable pressure between said press wheel, said fibrous combustible material and said die;

a controlled and variable temperature within said fixed die; and

an outlet releasing fibrous combustible pellets formed from said fibrous combustible material out of said fixed flat die extruder.

16. The fixed flat die extruder of claim 15, wherein said at least one press wheel rolls about a horizontal axis.

17. The fixed flat die extruder of claim 16, wherein said horizontal axis further spins about a vertical axis.

18. The fixed flat die extruder of claim 15, further comprising a means to vary a speed of said traversal, wherein said speed varying means controls and varies said pressure.

19. The fixed flat die extruder of claim 15, further comprising temperature-controlled water thermally coupled with said fixed die and controlling said die temperature.