Lightweight coated extruded granular absorbent
Method and coated lightweight granular absorbent formed of lightweight inner cores made of extruded pellets coated with powdered smectite, preferably bentonite, to form an outer sorbent smectite shell around each pellet producing lightweight sorbent granules where the pellets have sufficient water soluble binder to facilitate shell formation and clumping during sorbent use. When lightweight sorbent granules are wetted, clumps are formed that shrink during drying producing a clean, generally non-sticking clump having a high clump retention rate of at least 92% and/or a crush strength of at least 15 PSI. In a preferred method, the pellets are dried coated with dry powdered smectite before wetting using an atomizer or mister while turbulently directing air towards the pellets and powdered smectite to coat the pellets with the powdered smectite forming the outer sorbent shell while minimizing pellet shrinkage and densification. Such lightweight granular sorbent is well suited for use as litter.
1 . A self-clumping litter comprised of a plurality of pairs of absorbent pellets, wherein each absorbent pellet is comprised of a starch and a water-soluble binder, wherein each absorbent pellet absorbs at least 3.5 times its weight in water or urine, and wherein a plurality of pairs of the absorbent pellets clumps together when wetted with water or urine.
2 . The self-clumping litter of claim 1 , wherein each absorbent pellet is comprised of at least 7.5% water-soluble binder by pellet weight.
3 . The self-clumping litter of claim 2 , wherein each absorbent pellet is comprised of at least 15% water solubles content by pellet weight.
4 . The self-clumping litter of claim 2 , wherein the water-soluble binder in each absorbent pellet is comprised of dextrin.
5 . The self-clumping litter of claim 2 , wherein each absorbent pellet is comprised of at least 7.5% dextrin by pellet weight.
6 . The self-clumping litter of claim 1 , wherein the water-soluble binder in each absorbent pellet is comprised of dextrin, and wherein each absorbent pellet is comprised of at least 7.5% dextrin.
7 . The self-clumping litter of claim 1 , wherein at least 7.5% of the water-soluble binder in each absorbent pellet has a molecular weight within +25% of 504.43708 grams per mole.
8 . The self-clumping litter of claim 1 , wherein each absorbent pellet is further comprised of a cellulosic material.
9 . The self-clumping litter of claim 8 , wherein the cellulosic material in each absorbent pellet is comprised of one or more of a paper, a wood, a plant, and a grain.
10 . The self-clumping litter of claim 9 , wherein the cellulosic material in each absorbent pellet is comprised of one or more of sawdust, wood shavings, oat, alfalfa, rice, and beet.
11 . The self-clumping litter of claim 1 , wherein the water soluble binder has a molecular weight of between 8×10 4 and 10 6 g/mol.
12 . The self-clumping litter of claim 1 , wherein each absorbent pellet is further comprised of one of a charcoal and an activated carbon.
13 . The self-clumping litter of claim 1 , wherein each absorbent pellet has a water activity level of no greater than 0.4.
14 . The self-clumping litter of claim 1 , wherein each absorbent pellet is comprised of extrudate extruded from an admixture comprised of one or more cereal grains.
15 . The self-clumping litter of claim 1 , wherein the water-soluble binder has a degree of polymerization falling between 500 and 6,000 glucose units.
16 . The self-clumping litter of claim 1 , wherein each absorbent pellet is further comprised of one of calcium carbonate, sodium bicarbonate and silica.
17 . The self-clumping litter of claim 1 , wherein a clump formed of a plurality of pairs of the absorbent pellets wetted with water or urine shrinks at least 5% after formation as the clump dries.
18 . The self-clumping litter of claim 1 , wherein each absorbent pellet has starch damage in an amount of at least 50% as measured in accordance with AOAC: 2002.02.
19 . The self-clumping litter of claim 1 , wherein each absorbent pellet is further comprised of an outer shell formed around the absorbent pellet, the outer shell comprised of particles bonded together by the water-soluble binder.
20 . The self-clumping litter of claim 19 , wherein the outer shell is absorbent and comprised of particles of a smectite bonded together by the water-soluble binder.
21 . A self-clumping litter comprised of a plurality of pairs of absorbent pellets, wherein each absorbent pellet is comprised of a starch, a water-soluble binder comprised of at least 7.5% dextrin by pellet weight, and a cellulosic material, wherein each absorbent pellet absorbs at least 3.5 times its weight in water or urine, and wherein a plurality of pairs of the absorbent pellets clumps together when wetted with water or urine.
22 . The self-clumping litter of claim 21 , wherein each absorbent pellet is comprised of at least 7.5% water-soluble binder and at least 15% water solubles content by pellet weight.
23 . The self-clumping litter of claim 21 , wherein the water-soluble binder in each absorbent pellet has a molecular weight within ±25% of 504.43708 grams per mole.
24 . The self-clumping litter of claim 21 , wherein the cellulosic material in each absorbent pellet is comprised of one or more of a paper, a wood, a plant, and a grain.
25 . The self-clumping litter of claim 21 , wherein each absorbent pellet is further comprised of one of a charcoal and an activated carbon.
26 . The self-clumping litter of claim 21 , wherein each absorbent pellet has a water activity level of no greater than 0.4.
27 . The self-clumping litter of claim 21 , wherein each absorbent pellet is comprised of extrudate extruded from an admixture comprised of one or more cereal grains.
28 . The self-clumping litter of claim 21 , wherein the water-soluble binder has a degree of polymerization falling between 500 and 6,000 glucose units.
29 . The self-clumping litter of claim 21 , wherein each absorbent pellet is further comprised of one of calcium carbonate, sodium bicarbonate and silica.
30 . The self-clumping litter of claim 21 , wherein a clump formed of a plurality of pairs of the absorbent pellets wetted with water or urine shrinks at least 5% after formation as the clump dries.
31 . The self-clumping litter of claim 21 , wherein each absorbent pellet has starch damage in an amount of at least 50% as measured in accordance with AOAC: 2002.02.
32 . The self-clumping litter of claim 21 , wherein each adsorbent pellet is further comprised of an outer shell formed around the absorbent pellet, the outer shell comprised of particles bonded together by the water-soluble binder.
33 . The self-clumping litter of claim 32 , wherein the outer shell is absorbent and comprised of particles of a smectite bonded together by the water-soluble binder.
34 . A self-clumping litter comprised of a plurality of pairs of absorbent pellets, wherein each absorbent pellet is comprised of a starch and at least 7.5% dextrin by pellet weight, wherein each absorbent pellet absorbs at least 3.5 times its weight in water or urine, and wherein a plurality of pairs of the absorbent pellets clumps together when wetted with water or urine.
35 . The self-clumping litter of claim 34 , wherein each absorbent pellet is further comprised of a cellulosic material.
36 . The self-clumping litter of claim 35 , wherein the cellulosic material is comprised of a cellulose fiber.
37 . The self-clumping litter of claim 34 , wherein each absorbent pellet is further comprised of one of a charcoal and an activated carbon.
38 . The self-clumping litter of claim 34 , wherein each absorbent pellet has a water activity level of no greater than 0.4.
39 . A self-clumping litter comprised of a plurality of pairs of absorbent pellets, wherein each absorbent pellet is comprised of a starch, at least 7.5% dextrin by pellet weight, and a cellulosic material, wherein each absorbent pellet has a water activity level of no greater than 0.4, wherein each absorbent pellet absorbs at least 3.5 times its weight in water or urine, and wherein a plurality of pairs of the absorbent pellets clumps together when wetted with water or urine.
40 . The self-clumping litter of claim 39 , wherein each absorbent pellet is further comprised of one of a charcoal and an activated carbon.