Fiber separation process

• US 5,316,150 A
• Filed: 03/02/1993
• Issued: 05/31/1994
• Est. Priority Date: 03/02/1993
• Status: Expired due to Fees

• Current Assignee: Gordon Fisher
• Original Assignee: Gordon Fisher
• Inventors: Fisher, Gordon
• Primary Examiner(s): Bollinger, David H.
• Application Number:
  US08/025,262
• Time in Patent Office: 455 Days
• Field of Search: 209/12, 209/30, 209/31, 209/33, 209/44.1, 209/44.3, 209/22, 209/23
• US Class Current: 209/30
• CPC Class Codes: B07B 9/00 Combinations of apparatus for screening or sifting or for separating solids from solids using gas currents; General arrangement of plant, e.g. flow sheets
• CPC Class Codes: D01B 1/10 Separating vegetable fibres from stalks or leaves
• CPC Class Codes: D01B 1/40 Arrangements for disposing of non-fibrous materials

Abstract

A method for separating the long outer bast fibers from the short woody inner core fibers of herbaceous fiber producing plants which includes the steps of requiring that such plants harvested at a certain cut length are processed through a first and second stage core separator, each of which includes a rotating spiked cylinder and a set of angled moving conveyors for coarse separation of the bast and core fibers; then processed through a first and second incline core separator each of which include a series of rotating spiked cylinders provided at an inclined angle; then introduced into a single saw separator; then passed through a jet air separator having an adjustable blade therein; and finally, run through a four cylinder fiber cleaner. Each of these steps provides further and more complete separation of the woody core fibers from the longer bast fibers so that by the time the bast fibers exit the four cylinder cleaner they are over ninety-eight percent (98%) free of the woody core fibers. The core fibers which exit the various separators of the process are all channeled into a hammermill for grinding, and then transported into a large tilted rotating screened core fiber sizing drum.

Claims

1. A method for separating the long outer bast fibers from the short woody inner core fibers of herbaceous fiber producing plants comprising the steps of:

a. harvesting the plants using a short cut length;

b. introducing the plants so harvested into a first core separator wherein the harvested plant fibers come into contact with a rotating spiked cylinder partially surrounded by a concave grated housing, said cylinder mounted adjacent to a means for producing air flow, said means mounted adjacent to a plurality of upwardly inclined moving conveyor surfaces having openings therein, whereby many of the woody innercore plant fibers are caught by the spikes in said cylinder and thrown through said grated housing leaving the longer outer bast fibers to pass onto said moving conveyor by said air flow means such that as said conveyors move said fibers upward, many more of the woody innercore fibers drop through the openings therein;

then

c. introducing the bast fibers output from the first core separator into an identical second core separator; and

then

d. introducing the bast fibers from the previous step into a first incline separator wherein the fibers come into contact with a plurality of synchronously rotating spiked cylinders mounted adjacent to each other on an incline and above a set of grid bars having openings between them wherein, as the bast fibers are worked upward on the spiked cylinders, innercore fibers are removed and drop through the grid bar openings;

then

e. introducing the bast fibers output from the first incline separator into a second incline separator which is identical to the first incline separator except that the openings between the grid bars of said second incline separator are more narrow than the openings between the grid bars of the first incline separator; and

then

f. introducing the bast fibers from the previous step into a saw cleaner wherein the fibers come into contact with a cylinder around which a spiked wire has been tightly wrapped, said cylinder mounted above a set of stationary grid bars, so that centrifugal force throws the innercore fibers through the grid bars and the separated bast fibers exit the saw cleaner;

then

g. introducing the bast fibers from the previous step into a jet air fiber separator wherein the fibers are blown against the facing edge of an adjustable blade for separation;

then

h. introducing the bast fibers from the previous step into a four cylinder fiber cleaner wherein the fibers come into contact with four (4) synchronously rotating level-mounted spiked cylinders which are mounted above a set of horizontal grid bars under which a suction is applied, so that any remaining innercore fibers fall through the grid bars and very clean bast fibers exit the cleaner.

2. The method according to claim 1 wherein a plurality of inwardly protruding spikes are mounted on the housings adjacent to the spiked cylinders of the first and second core separators.

3. The method according to claim 2 wherein the cut length of the harvested plants is between three inches (3") and eight inches (8").

4. The method according to claim 3 wherein the harvested plants are introduced to the first core separator by vacuum suction, and the means for producing air flow in said first and second core separators is a rotating cylinder having an uneven surface thereon.

5. The method according to claim 4 wherein the innercore fibers produced are transported via air suction to a hammermill for grinding and then to a tiled rotating screened drum for sizing.

6. The method according to claim 5 wherein the openings in the screens around the upper half of the tilted rotating drum are wider than the openings in the screens around the lower half thereof.

7. The method according to claim 6 wherein the openings in the inclined moving conveyor surface of the first and second core separators are approximately one and one-half inch (11/2") by approximately two inches (2").

8. The method according to claim 7 wherein seven (7) rotating spiked cylinders are provided in the first and second incline separator.

9. The method according to claim 8 wherein the rotating spiked cylinders provided in the first and second incline separator are tilted at an angle of less than sixty (60) degrees.

10. The method according to claim 9 wherein the grid bars are located approximately one quarter inch (1/4") below the rotating spiked cylinders provided in the first and second incline separators.

11. The method according to claim 10 wherein the distance separating the grid bars below the rotating spiked cylinders provided in the first incline separator is approximately one inch (1"), and the distance separating the grid bars below the rotating spiked cylinders provided in the second incline separator is approximately one-half inch (1/2").

12. The method according to claim 11 wherein approximately three (3) spikes per inch are provided in the spiked wire of the saw cleaner.

13. The method according to claim 12 wherein the wraps of the spiked wire around the cylinder of the saw cleaner are approximately one inch (1") apart.

14. The method according to claim 13 wherein the level-mounted cylinders of the fiber cleaner are mounted approximately one quarter inch (1/4") above the grid bars thereof.

15. The method according to claim 14 wherein the horizontal grid bars of the fiber cleaner are separated by a distance of approximately one inch (1").

16. The method according to claim 15 wherein the rotating spiked cylinders provided in the first and second incline separator are tilted at an angle of approximately thirty-five (35) degrees.

17. The method according to claim 16 wherein the openings in the screens around the upper half of the tilted rotating drum are approximately one-half inch (1/2") in diameter, and the openings in the screens around the lower half thereof are approximately one-eighth inch (1/8") in diameter.

18. The method according to claim 2 wherein the cut length of the harvested plants is between three inches (3") and five inches (5").