Porous low density shot-like degradable absorbent materials and manufacturing process therefor

Claim 2

A process for forming discrete, shot-like, absorbent pellets having a bulk density in the range of from about 13 lbs./ft. 3 to less than 30 lbs./ft 3 and minimal inorganic solids content wherein each of the pellets is characterized by: i) a smooth, soft, porous, compressible, generally rounded external configuration essentially devoid of projecting fiber ends; ii) a soft, open, porous compressible, internal fiber structure; and iii), an absorptive capacity in terms of percentage by volume in excess of about 53%, said process comprising the steps of: a) obtaining cellulose fiber materials having minimal inorganic solids content; b) rehydrating the cellulose fiber materials to produce a water/fiber slurry comprising on the order of about 96.5% water by weight and about 3.5% total solids by weight; c) de-watering the slurry to form a shreddable press cake containing total solids in the range of about 15% to about 50% by weight; d) shredding the press cake to form discrete particles each having a maximum dimension of not more than about 1/2"; e) rolling the discrete shredded particles formed in Step (d) in an agglomerator so as to gather a plurality of discrete shredded particles into soft, discrete, shot-like, agglomerated, compressible pellets each having a smooth, soft, porous, compressible outer surface essentially devoid of projecting fiber ends and a soft, open, porous, compressible internal fiber structure; and, f) drying the pellets formed in Step (e) to remove excess water resulting in discrete shot-like pellets having a total dry solids content in excess of 75% by weight, a bulk density in the range of from about 13 lbs./ft. 3 to less than 30 lbs./ft. 3 , and an absorptive capacity in terms of percentage by volume in excess of about 53%.

Claim 3

A process for forming discrete, shot-like absorbent pellets having a bulk density in the range of about 13 to about 18 lbs./ft. 3 and minimal inorganic solids content wherein each of the discrete pellets is characterized by: i) a smooth, soft, porous, compressible, generally rounded external configuration essentially devoid of projecting fiber ends; ii) a soft, open, porous, compressible, internal fiber structure; and iii), an absorptive capacity in terms of percentage by volume in excess of about 53% said process comprising the steps of: a) obtaining cellulose fiber materials having minimal inorganic solids content; b) rehydrating the cellulose fiber materials to produce a water/fiber slurry comprising on the order of about 96.5% water by weight and about 3.5% total solids by weight; c) de-watering the slurry to form a shreddable press cake containing approximately 25% total solids by weight; d) introducing the press cake into a first coarse shredding device such as one of a cake breaker and a cut-and-fold screw conveyor and reducing the press cake to particles smaller in size than about 4"×2"×1/2"; e) introducing the particles formed in Step (d) into a second shredding device such as one of a high shear turbulator, a high shear blender and a high shear shredder and reducing the particle size to approximately 1/2" maximum size; f) delivering the particles formed in Step (e) to one of a rotary pan agglomerator, a drum agglomerator and a rotary dryer; and, rolling such particles therein to gather a plurality of discrete shredded particles into pellets having: i) smooth, soft, porous, compressible, shot-like external configurations essentially devoid of projecting fiber ends; and ii), soft, open, porous, compressible, internal fiber structures; and, g) drying the shot-like pellets formed in Step (f) to remove excess water resulting in discrete, smooth, soft, compressible, shot-like, porous absorbent fiber pellets having a total solids content in the range of about 88% to about 95% dry solids by weight, a bulk density in the range of about 13 to about 18 lbs./ft. 3 and an absorptive capacity in terms of percentage by volume in excess of about 53%.

Claim 4

A process for forming discrete, shot-like absorbent pellets having a bulk density in the range of about 13 to about 18 lbs./ft. 3 and minimal inorganic solids content wherein each of the discrete pellets is characterized by: i) a smooth, soft, porous, compressible, generally rounded external configuration essentially devoid of projecting fiber ends; ii) a soft, open, porous, compressible, internal fiber structure; and iii), an absorptive capacity in terms of percentage by volume in excess of about 53% said process comprising the steps of: a) obtaining cellulose fiber materials having minimal inorganic solids content; b) rehydrating the cellulose fiber materials to produce a water/fiber slurry comprising on the order of about 96.5% water by weight and about 3.5% total solids by weight; c) de-watering the slurry to form a shreddable press cake containing approximately 25% total solids by weight; d) introducing the press cake into a first coarse shredding device such as one of a cake breaker and a cut-and-fold screw conveyor and reducing the press cake to particles smaller in size than about 4"×2"×1/2"; e) introducing the particles formed in Step (d) into a second shredding device such as one of a high shear turbulator, a high shear blender and a high shear shredder and reducing the particle size to approximately 1/2" maximum size; f) delivering the particles formed in Step (e) to one of a rotary pan agglomerator, a drum agglomerator and a rotary dryer; and, rolling such particles therein to gather a plurality of discrete shredded particles into pellets having: i) smooth, soft, porous, compressible, shot-like external configurations essentially devoid of projecting fiber ends; and ii), soft, open, porous, compressible, internal fiber structures; and, g) drying the shot-like pellets formed in Step (f) to remove excess water resulting in discrete, smooth, soft, compressible, shot-like, porous absorbent fiber pellets having a total solids content in the range of about 88% to about 95% dry solids by weight, a bulk density in the range of about 13 to about 18 lbs./ft. 3 and an absorptive capacity in terms of percentage by volume in excess of about 53%.

Claim 5

The discrete shot-like absorbent pellets prepared by the process of claims 1 or 2.

Claim 6

A process for forming discrete, shot-like, absorbent pellets as set forth in claims 1 or 2 wherein the pellets produced are of diverse sizes ranging up to about 6.2 mm and wherein at least about 90% of the pellets produced will pass through a 6.2 mm sieve while less than about 14% of the pellets produced will pass through a 1.2 mm sieve.

Claim 7

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 4 wherein the sizes of the pellets produced closely approximate the size characteristics of conventional inorganic clay absorbents.

Claim 8

A process for forming discrete shot-like, absorbent pellets as set forth in claims 1 or 2 wherein a pH modifying material is added to the slurry formed in Step (b) in sufficient quantity to adjust the pH value of the slurry to a level in the range of 4.5 to 6.5.

Claim 9

A process for forming discrete shot-like, absorbent pellets as set forth in claim 6 wherein the pH modifying material is aluminum sulfate.

Claim 10

A process for forming discrete shot-like, absorbent pellets as set forth in claims 1 or 2 wherein a flocculent is added to the slurry formed in Step (b) prior to the de-watering step set forth in Step (c) in an amount sufficient to initiate flocculation of the materials in the slurry.

Claim 11

A process for forming discrete shot-like, absorbent pellets as set forth in claim 6 wherein a flocculent is added to the slurry formed in Step (b) prior to the de-watering step set forth in Step (c) in an amount sufficient to initiate flocculation of the materials in the slurry.

Claim 12

A process for forming discrete, shot-like, absorbent pellets as set forth in claims 1 or 2 wherein an internal size is added to the slurry prior to de-watering in Step (c) in sufficient quantity to render the absorbent pellets produced hydrophobic.

Claim 13

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 6 wherein an internal size is added to the slurry prior to de-watering in Step (c) in sufficient quantity to render the absorbent pellets produced hydrophobic.

Claim 14

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 8 wherein an internal size is added to the slurry prior to de-watering in Step (c) in sufficient quantity to render the absorbent pellets produced hydrophobic.

Claim 15

The discrete shot-like absorbent pellets formed by the process of claim 8.

Claim 16

A process for forming discrete, shot-like, absorbent pellets as set forth in claims 1 or 2 wherein a water soluble deodorizing agent is added to the product prior to shredding the product to form particles having a maximum dimension of approximately 1/2".

Claim 17

The discrete shot-like absorbent pellets formed by the process of claim 14 suitable for use as an animal bedding material.

Claim 18

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 1 wherein during de-watering Step (c) sufficient excess water is removed from the press cake to reduce its total solids content to approximately 25% by weight.

Claim 19

A process of forming discrete shot-like, absorbent pellets as set forth in claim 1 wherein an absorption enhancing additive is added to the particles during Step (d) in an amount up to 50% dry solids by weight.

Claim 20

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 17 wherein the absorption enhancing additive comprises a superabsorbent starch.

Claim 21

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 17 wherein the absorption enhancing additive comprises a superabsorbent polymer.

Claim 22

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 2 wherein an absorption enhancing additive is added to the particles during Step (e) in an amount up to 50% dry solids by weight.

Claim 23

A process for forming discrete, shot-like, absorbent pellets are set forth in claim 20 wherein the absorption enhancing additive comprises a superabsorbent starch.

Claim 24

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 20 wherein the absorption enhancing additive comprises a superabsorbent polymer.

Claim 25

The discrete shot-like absorbent pellets formed by the process of claims 17, 18, 19, 20, 21 or 22.

Claim 26

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 1 wherein an external size is added to the particles during Step (d) in sufficient quantity to render the absorbent pellets hydrophobic.

Claim 27

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 2 wherein an external size is added to the particles during Step (e) in sufficient quantity to render the absorbent pellets hydrophobic.

Claim 28

The discrete shot-like absorbent pellets formed by the process of claims 24 or 25.

Claim 29

A process for forming discrete, ball-like, absorbent pellets as set forth in claim 10 wherein an external size is added to the particles during shredding thereof to form particles having a maximum dimension of approximately 1/2" so as to enhance the hydrophobic properties of the absorbent pellets.

Claim 30

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 6 wherein an internal size is added to the slurry prior to de-watering in Step (c) in sufficient quantity to render the absorbent pellets produced hydrophobic and an external size is added to the particles during shredding thereof to form particles having a maximum dimension of approximately 1/2" so as to enhance the hydrophobic properties of the absorbent pellets.

Claim 31

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 1 wherein at least one of an agglomerant enhancing material, a surfactant, an odor controlling material, an aromatic scent and an external size is added to the particles during Step (e).

Claim 32

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 2 wherein at least one of an agglomerant enhancing material, a surfactant, an odor controlling material, an aromatic scent and an external size is added to the particles during Step (f).

Claim 33

A process for forming discrete, shot-like, absorbent pellets as set forth in claims 1 or 2 wherein the drying step is conducted at a temperature range of from about 170° C. to 240° C. for a period of approximately fifteen minutes.

Claim 34

A process for forming discrete, shot-like, absorbent pellets as set forth in claim 1 or 2 wherein a bio-nutrient/enzyme is added to the particles during shredding thereof to form particles having a maximum dimension of approximately 1/2".