초록 ▼

An extruder (20) is specifically designed for the production of animal feed products (e.g., aquatic feeds) containing substantial quantities of low-cost fibrous materials, such as rice byproducts, at high production rates. The extruder (20) includes an elongated barrel (22) with a screw assembly (24

An extruder (20) is specifically designed for the production of animal feed products (e.g., aquatic feeds) containing substantial quantities of low-cost fibrous materials, such as rice byproducts, at high production rates. The extruder (20) includes an elongated barrel (22) with a screw assembly (24) within the barrel and an endmost extrusion die assembly (34). The screw assembly (24) includes an inlet screw assembly (42) and a processing screw assembly (44). The assembly (44) includes screw components (50-56) of differential pitch to present a long pitch inlet section (64) and a tight pitch discharge section (68). Materials passing through the screw assembly (24) are successively subjected to high levels of steam injection (STE) followed by high levels of friction and shear (SME), so that the STE/SME ratio is at least about 6/1.

대표청구항 ▼

1. A single screw extruder processing screw assembly comprising a plurality of screw components in end-to-end alignment with each screw component including an elongated shaft and outwardly extending helical flighting along the length of said shaft, said flighting being of the same hand and presentin

1. A single screw extruder processing screw assembly comprising a plurality of screw components in end-to-end alignment with each screw component including an elongated shaft and outwardly extending helical flighting along the length of said shaft, said flighting being of the same hand and presenting an inlet portion, an intermediate portion, and a discharge portion, the pitch x diameter values of said inlet, intermediate, and discharge portions being different, and including at least one flow-restricting element between the discharge portion of one of said components, and the inlet portion of the next adjacent component, said inlet portion having a length L1, a fighting diameter D1, and a pitch P1, said intermediate portion comprising first and second sub-portions, said first sub-portion having a length L2, a flighting diameter D2, and a pitch P2, said second sub-portion having a length L3, a fighting diameter D3, and a pitch P3, and said discharge portion having a length L4, a flighting diameter D4, and a pitch P4, said inlet portion having an L1/D1 ratio of from about 0.8-2 and a pitch P1×D1 of from about 1.5-2.8, said first sub-portion having an L2/D2 ratio of from about 0.1-0.7 and a pitch P2×D2 of from about 1.0-2.0, said second sub-portion having an L3/D3 ratio of from about 0.05-0.9 and a pitch P3×D3 of from about 0.5-2.0, said discharge portion having an L4/D4 ratio of from about 0.1-0.9 and a pitch P4×D4 of from about 0.1-0.9, the length L1 being greater than the individual lengths L2, L3, and L4, and also greater than the combined length of L2 and L3. 2. The assembly of claim 1, said inlet portion having a wrap W1 of from about 180-450°, said first sub-portion having a wrap W2 of from about 45-180° said second sub-portion having a wrap W3 of from about 90-360°, and said discharge portion having a wrap W4 of from about 180-450°. 3. The assembly of claim 1, said inlet portion having a fighting surface S1 of from about 1245-2105 sq·cm, said first sub-portion having a fighting surface S2 of from about 318-537 sq·cm, said second sub-portion having a flighting surface S3 of from about 501-846 sq·cm, and said discharge portion having a fighting surface S4 of from about 650-1098 sq·cm. 4. The assembly of claim 1, said inlet portion having a free volume V1 of from about 6870-11610 cc, said first sub-portion having a free volume V2 of from about 1500-2536 cc, said second sub-portion having a free volume V3 of from about 2160-3173 cc, and said discharge portion having a free volume V4 of from about 1563-2642 cc. 5. The assembly of claim 1, the pitch P1 of said inlet portion throughout the axial length thereof being greater than the pitch P4 of said discharge portion. 6. The assembly of claim 1, said L1/D1 being greater than any of said L2/D2, L3/D3, or L4/D4. 7. The assembly of claim 1, said P1×D1 being greater than any of said P2×D2, P3×D3, or P4×D4. 8. The assembly of claim 1, said W4 being greater than any of said W1, W2, or W3. 9. The assembly of claim 1, said S1 being greater than any of said S2, S3, or S4. 10. The assembly of claim 1, said V1 being greater than any of said V2, V3, or V4. 11. The assembly of claim 1, said D1, D2, D3, and D4 being equal. 12. A single screw extruder comprising: an elongated barrel having an inlet adjacent one end thereof and a restricted opening die assembly adjacent the opposite end thereof;a single axially rotatable processing screw assembly located within said barrel between said inlet and said die assembly,said assembly comprising a plurality of screw components in end-to-end alignment with each screw component including an elongated shaft and outwardly extending helical fighting along the length of said shaft, said flighting being of the same hand and presenting an inlet portion, an intermediate portion, and a discharge portion, the pitch x diameter values of said inlet, intermediate, and discharge portions being different, and including at least one flow-restricting element between the discharge portion of one of said components, and the inlet portion of the next adjacent component, said inlet portion having a length L1, a fighting diameter D1, and a pitch P1, said intermediate portion comprising first and second sub-portions, said first sub-portion having a length L2, a fighting diameter D2, and a pitch P2, said second sub-portion having a length L3, a fighting diameter D3, and a pitch P3, and said discharge portion having a length L4, a flighting diameter D4, and a pitch P4,said inlet portion having an L1/D1 ratio of from about 0.8-2 and a pitch P1×D1 of from about 1.5-2.8, said first sub-portion having an L2/D2 ratio of from about 0.1-0.7 and a pitch P2×D2 of from about 1.0-2.0, said second sub-portion having an L3/D3 ratio of from about 0.05-0.9 and a pitch P3×D3 of from about 0.5-2.0, said discharge portion having an L4/D4 ratio of from about 0.1-0.9 and a pitch P4×D4 of from about 0.1-0.9, the length L1 being greater than the individual lengths L2, L3, and L4, and also greater than the combined length of L2 and L3. 13. The extruder of claim 12, said inlet portion having a wrap W1 of from about 180-450°, said first sub-portion having a wrap W2 of from about 45-180° said second sub-portion having a wrap W3 of from about 90-360°, and said discharge portion having a wrap W4 of from about 180-450°. 14. The extruder of claim 12, said inlet portion having a fighting surface S1 of from about 1245-2105 sq·cm, said first sub-portion having a flighting surface S2 of from about 318-537 sq·cm, said second sub-portion having a fighting surface S3 of from about 501-846 sq·cm, and said discharge portion having a fighting surface S4 of from about 650-1098 sq·cm. 15. The extruder of claim 12, said inlet portion having a free volume V1 of from about 6870-11610 cc, said first sub-portion having a free volume V2 of from about 1500-2536 cc, said second sub-portion having a free volume V3 of from about 2160-3173 cc, and said discharge portion having a free volume V4 of from about 1563-2642 cc. 16. The extruder of claim 12, the pitch P1 of said inlet portion throughout the axial length thereof being greater than the pitch P4 of said discharge portion. 17. The extruder of claim 12, said L1/D1 being greater than any of said L2/D2, L3/D3, or L4/D4. 18. The extruder of claim 12, said P1×D1 being greater than any of said P2×D2, P3×D3, or P4×D4. 19. The extruder of claim 12, said W4 being greater than any of said W1, W2, or W3. 20. The extruder of claim 12, said S1 being greater than any of said S2, S3, or S4. 21. The extruder of claim 12, said V1 being greater than any of said V2, V3, or V4. 22. The extruder of claim 12, said D1, D2, D3, and D4 being equal.