Method of making extruded self-clumping granular absorbent
A granular absorbent and granular absorbent making method producing granular absorbent from a carbohydrate starch-containing cereal grain, e.g., corn, based admixture extruded from a single screw or twin screw extruder forming liquid absorbing pellets having a clumping agent formed during extrusion composed at least in part of carbohydrate polymer binder. Each pellet is extruded under conditions that cause formation of carbohydrate polymer binder clumping agent at least some of which is water soluble. One preferred method of extruding granular absorbent causes starch dextrinization to occur such that at least some of the carbohydrate polymer binder clumping agent in each liquid absorbing pellet of the granular absorbent is formed of dextrin. Each pellet can be coated such as with a smectite that preferably is bentonite. During use, clumping agent formed during extrusion of a pellet dissolves and flows in between and along adjacent pellets when the pellet(s) is/are wetted causes the pellets to “self-clump” without the presence of any clumping agent additive producing a granular absorbent that not only performs well but which is faster and easier to clean up as a resulf of its “self-clumping” formulation.
1. A method of making granular absorbent comprising gelatinizing an admixture comprised of starch in an extruder under sufficient pressure and temperature forming a clumping agent comprised of a carbohydrate polymer binder from at least some of the starch of the admixture during extrusion from the extruder producing a plurality of extruded liquid absorbing pellets having a bulk density no greater than 0.7 grams per cubic centimeter and comprised of a liquid soluble carbohydrate polymer binder clumping agent comprised of dextrin; and
wherein the admixture has a moisture content low enough and the extruder operates at an extrusion pressure and temperature high enough to dextrinize starch in the admixture during at least one of gelatinization and extrusion by the extruder forming dextrin in each liquid absorbing pellet.
2. The method of making granular absorbent of claim 1 wherein each liquid absorbing pellet has between 1% and 10% liquid soluble carbohydrate polymer clumping agent by pellet weight.
3. The method of making granular absorbent of claim 2 wherein the liquid soluble carbohydrate polymer binder clumping agent is water soluble.
4. The method of making granular absorbent of claim 1 wherein each liquid absorbing pellet has at least 5% water soluble carbohydrate polymer binder clumping agent by pellet weight.
5. The method of making granular absorbent of claim 4 wherein the admixture has a moisture content of no more than 18% by total wet admixture weight and the extruder is a single screw extruder that extrudes the plurality of liquid absorbing pellets at an extrusion pressure of at least 800 pounds per square inch and at extrusion temperature of at least 135° Celsius.
6. The method of making granular absorbent of claim 5 wherein the extruder operates under adiabatic extruder operating conditions during extruding the plurality of liquid absorbing pellets.
7. The method of making granular absorbent of claim 4 wherein each one of the plurality of liquid absorbing pellets is comprised of at least 0.1% dextrin by pellet weight.
8. The method of making granular absorbent of claim 1 wherein each one of the plurality of liquid absorbing pellets is comprised of at least 2% dextrin by pellet weight.
9. The method of making granular absorbent of claim 1 wherein each one of the plurality of liquid absorbing pellets is comprised of between 0.1% and 5% dextrin by pellet weight.
10. The method of making granular absorbent of claim 1 wherein each one of the plurality of liquid absorbing pellets is comprised of between 2% and 10% dextrin by pellet weight.
11. The method of making granular absorbent of claim 1 wherein the admixture is comprised of at least one cereal grain having a high carbohydrate content of at least 45% by cereal grain weight.
12. The method of making granular absorbent of claim 11 wherein the admixture comprises a dry admixture formed of at least 70% by dry admixture weight of at least one cereal grain having a high carbohydrate content of at least 45% by cereal grain weight.
13. The method of making granular absorbent of claim 1 , wherein each one of the plurality of liquid absorbing pellets is comprised of at least 1% of the carbohydrate polymer clumping agent by pellet weight.
14. A method of making granular absorbent comprising gelatinizing an admixture comprised of starch in an extruder under sufficient pressure and temperature forming a clumping agent comprised of a carbohydrate polymer binder from at least some of the starch of the admixture during extrusion from the extruder producing a plurality of extruded liquid absorbing pellets having a bulk density no greater than 0.7 grams per cubic centimeter and comprised of carbohydrate polymer binder clumping agent;
wherein the admixture is comprised of a dry admixture formed of at least 70% by dry admixture weight of at least one cereal grain having a high carbohydrate content of at least 45% by cereal grain weight; and
wherein each one of the plurality of liquid absorbing pellets is comprised of between 1% and 10% of the carbohydrate polymer binder clumping agent by pellet weight and wherein the carbohydrate polymer binder clumping agent is comprised of a water soluble carbohydrate polymer binder clumping agent.
15. The method of making granular absorbent of claim 14 wherein the admixture has a moisture content of no more than about 18% by total wet admixture weight and the extruder is a single screw extruder that extrudes the plurality of liquid absorbing pellets at an extrusion pressure of at least 800 pounds per square inch.
16. The method of making granular absorbent of claim 15 wherein the admixture comprises a dry admixture formed of at least 70% by dry admixture weight of at least one cereal grain having a high carbohydrate content of at least 65% by cereal grain weight and having a high starch content of at least 60% by cereal grain weight.
17. The method of making granular absorbent of claim 16 wherein the dry admixture is comprised of at least 70% corn by dry admixture weight.
18. The method of making granular absorbent of claim 17 wherein the corn is comprised of at least one of corn grits, corn meal, corn flour and corn starch.
19. The method of making granular absorbent of claim 18 wherein each liquid absorbing pellet is coated with an outer coating comprised of a smectite.
20. The method of making granular absorbent of claim 15 wherein the dry admixture is comprised of whole grain sorghum.
21. The method of making granular absorbent of claim 14 wherein the admixture has a moisture content of no more than 18% by total wet admixture weight and the extruder extrudes the plurality of liquid absorbing pellets at an extrusion pressure of at least 800 pounds per square inch and at extrusion temperature of at least 135° Celsius.
22. The method of making granular absorbent of claim 21 wherein the admixture comprises a dry admixture formed of at least 70% by dry admixture weight of at least one cereal grain having a high carbohydrate content of at least 65% by cereal grain weight and having a high starch content of at least 60% by cereal grain weight.
23. The method of making granular absorbent of claim 22 wherein the dry admixture is comprised of at least 70% corn by dry admixture weight.
24. The method of making granular absorbent of claim 23 wherein the corn is comprised of at least one of corn grits, corn meal, corn flour and corn starch.
25. The method of making granular absorbent of claim 24 wherein each liquid absorbing pellet is coated with an outer coating comprised of a smectite after extrusion.
26. The method of making granular absorbent of claim 24 wherein each liquid absorbing pellet has an outer coating comprised of bentonite.
27. The method of making granular absorbent of claim 1 wherein the extruder is a single screw extruder that extrudes the plurality of liquid absorbing pellets at an extrusion pressure of at least 900 pounds per square inch.
28. The method of making granular absorbent of claim 27 wherein the dry admixture is made of whole grain sorghum.
29. The method of making granular absorbent of claim 27 wherein the dry admixture is comprised of at least 70% corn by dry admixture weight.
30. The method of making granular absorbent of claim 29 wherein the corn is comprised of at least one of corn grits, corn meal, corn flour and corn starch.
31. The method of making granular absorbent of claim 30 wherein the liquid soluble carbohydrate polymer binder is comprised of at least 5% water soluble carbohydrate polymer binder clumping agent.
32. The method of making granular absorbent of claim 31 wherein each liquid absorbing pellet is coated with an outer coating comprised of a smectite after extrusion.
33. The method of making granular absorbent of claim 32 wherein each liquid absorbing pellet has an outer coating comprised of bentonite.
34. A method of making granular absorbent comprising gelatinizing an admixture comprised of starch in an extruder under sufficient pressure and temperature forming a water soluble clumping agent comprised of a carbohydrate polymer binder from at least some of the starch of the admixture during extrusion from the extruder producing a plurality of extruded liquid absorbing pellets having a bulk density no greater than 0.7 grams per cubic centimeter and comprised of water soluble carbohydrate polymer binder clumping agent;
wherein the extruder extrudes the plurality of liquid absorbing pellets at an extrusion pressure of between 900 pounds per square inch and 1,200 pounds per square inch and at an extrusion temperature of between 140° Celsius and 165° Celsius; and
wherein starch dextrinization occurs during one of gelatinizing and extruding of the plurality of liquid absorbing pellets from the extruder producing liquid absorbing pellets each comprised of dextrin.
35. The method of making granular absorbent of claim 34 wherein the admixture comprises a dry admixture formed of at least 70% by dry admixture weight of at least one cereal grain having a high carbohydrate content of at least 65% by cereal grain weight and having a high starch content of at least 60% by cereal grain weight.
36. The method of making granular absorbent of claim 35 wherein each one of the plurality of liquid absorbing pellets is comprised at least 0.1% dextrin by weight.
37. The method of making granular absorbent of claim 35 wherein each one of the plurality of liquid absorbing pellets is comprised at least 2% dextrin by weight.
38. The method of making granular absorbent of claim 35 wherein each one of the plurality of liquid absorbing pellets is comprised of at least 5% water soluble carbohydrate polymer binder clumping agent by pellet weight.
39. The method of making granular absorbent of claim 35 wherein each one of the plurality of liquid absorbing pellets is comprised of between 1% and 10% water soluble carbohydrate polymer binder clumping agent by pellet weight.
40. The method of making granular absorbent of claim 35 wherein each liquid absorbing pellet is coated with an outer coating comprised of a smectite after extrusion.
41. The method of making granular absorbent of claim 35 wherein each liquid absorbing pellet has an outer coating comprised of bentonite.
42. The method of making granular absorbent of claim 35 wherein the at least one cereal grain is comprised of at least one of corn grits, corn meal, corn flour and corn starch.