Wet pulping system and method for producing cellulosic insulation with low ash content

• US 7,758,719 B2
• Filed: 12/14/2006
• Issued: 07/20/2010
• Est. Priority Date: 12/16/2005
• Status: Active Grant

• Current Assignee: Fiberight LLC
• Original Assignee: Fiberight Management, LLC (Fiberight LLC)
• Inventors: Oganesoff, Eric M., Gerber, Steven A., Gerber, Milton L., Stuart-Paul, Craig
• Primary Examiner(s): Hug; Eric
• Assistant Examiner(s): MINSKEY, JACOB T
• Application Number:
  US11/610,977
• Publication Number:
  US 20070137805A1
• Time in Patent Office: 1,314 Days
• Field of Search: 210/928, 162/4, 162/5
• US Class Current: 162/4
• CPC Class Codes: A01K 1/0152 Litter
• CPC Class Codes: A01K 1/0155 comprising organic material
• CPC Class Codes: D21B 1/026 Separating fibrous materials from waste
• CPC Class Codes: D21B 1/16 in the presence of chemical agents
• CPC Class Codes: D21B 1/32 of waste paper
• CPC Class Codes: D21C 11/00 Regeneration of pulp liquors or effluent waste waters
• CPC Class Codes: D21C 5/02 Working-up waste paper mechanical part D21B1/08, D21B1/32
• CPC Class Codes: Y02W 30/64 Paper recycling
• CPC Class Codes: Y10S 210/928 Paper mill waste, e.g. white water, black liquor treated

Abstract

Apparatus and method for recovering organic cellulosic fibers from landfill materials (such as post consumer, municipal and industrial waste materials). The apparatus and method selectively introduces waste materials containing organic cellulosic fibers into a size reduction machine. The pre-cleaned waste materials are conveyed to a tank, drum, or tunnel type fiber recovery apparatus. The waste materials are subjected to mechanical and fluid fiberization for a selected period of time to produce useful products, such as cellulosic insulation with a total ash content equal to or less than 10%, as well animal and fowl bedding products that is substantially devoid of moisture content, among other products.

Claims

1. A method for producing cellulosic fibers from mixed trash comprising:

a. loading waste containing cellulosic fibers and other non-organic materials into a sorting apparatus to produce a combination of short and long fiber feedstock;

b. blending the sorted trash to maintain a ratio of about 50% to about 90% short fiber feedstock and about 10% to about 50% long fiber feedstock;

c. shredding the blended sorted fiber feedstock;

d. weighing the shredded fiber feedstock into load sizes of about 100 to about 300 lbs;

e. pulping the weighed fiber feedstock into cellulosic fibers and a first through fourth group of select waste materials with pulping fluids in a fiber extractor recovery apparatus thereby impregnating the cellulosic fibers with the pulping fluids;

f. draining the cellulosic fibers from the extractor fiber recovery apparatus into a hydro-cleaner;

g. de-watering the impregnated cellulosic fibers in the hydro-cleaner to reduce the amount of pulping fluid in the impregnated cellulosic fibers, and extracting a portion of the second group of select waste materials;

h. depositing the extracted portion of the second group of select waste materials into a landfill;

i. fluffing the de-watered cellulosic fibers in a first disk refiner;

j. thickening the fluffed cellulosic fibers in a thickener and extracting pulping fluid for re-use in the fiber extractor recovery apparatus;

k. storing the thickened cellulosic fibers in a stock chest apparatus;

l. extracting pulping fluid from the thickened cellulosic fibers in a pulping fluid extractor;

m. impregnating additional chemicals comprising fire retardant chemicals, dyes, insecticides, and/or biocides, such that the final cellulosic fiber product comprises a flame retardant loading of about 6%;

n. extracting excess pulping fluid from the thickened cellulosic fibers in a pulp press thereby producing partially dried thickened cellulosic fibers;

o. fluffing the partially dried thickened cellulosic fibers in a fluffer apparatus that reduces a density of the cellulosic fibers from a first range of about 6 to about 10 lbs per cubic foot to a second density range from about 2 to about 6 lbs per cubic foot, with a post fluffing moisture content of about 40% to about 60%;

p. additionally fluffing the cellulosic fibers in a second disk refiner at a temperature between about 150°

F. and about 700°

F.;

q. drying the cellulosic fibers in a dryer to further reduce the moisture content to about 10% to about 18%; and

s. packaging or baling the dried cellulosic fibers.

2. The method according to claim 1, wherein the step of pulping comprises:

i. rotating and agitating the shredded fiber feedstock in a plurality of fiber recovery apparatuses into cellulosic fibers and first through fourth groups of select waste materials, each of the fiber recovery apparatuses containing pulping fluid, wherein the pulping fluid comprises a combination of water, fire retardant chemicals, biocides, dyes, insecticides and surfactants;

ii. impregnating the cellulosic fibers and the first through fourth select waste materials with fire resistant chemicals, dyes, chemical insecticides, and/or biocides;

iii. separating the impregnated cellulosic fibers from the first group of select waste materials that are not utilized or desired in separator fiber recovery apparatuses;

iv. extracting the first group of select waste materials dissolved within the pulping fluid from the cellulosic fibers in a dirty water tank, DAF contaminant separator, waste tank, and sludge press and then depositing the first group of select waste materials into a landfill;

v. separating the impregnated cellulosic fibers from the second group of select waste materials in an extractor fiber recovery apparatus; and

vi. extracting the second group of select waste materials from the impregnated cellulosic fibers.

3. The method according to claim 2, further comprising:

t. transferring pulping fluid extracted from the pulping fluid extractor and pulp press to a dirty water storage chest to extract at least one additional inorganic compound selected from the group consisting of calcium carbonate, aluminum and magnesium hydroxide;

u. adding one or more acids to the water and pulping fluid stored in the dirty water storage chest to lower the pH of the pulping fluid to a range of about 4.0 to about 5.0;

v. mixing the pulping fluids in a first precipitator with one or more alkaline agents to increase the pH of the pulping fluid to a range of about 4.5 to about 6.0 to cause precipitation of aluminum and magnesium hydroxide byproducts;

w. centrifuging the mixture of pulping fluids and precipitated aluminum and magnesium hydroxide byproducts in a first centrifuge to separate and discard the aluminum and magnesium hydroxide byproducts;

x. adding carbon dioxide to the first centrifuged pulping fluids;

y. mixing the pulping fluids in a second precipitator with one or more additional alkaline agents to increase the pH of the carbonated pulping fluids to a range of about 11.5 to about 12.8 or to a pH point wherein calcium carbonate precipitates from the carbonated pulping fluids;

z. centrifuging the mixture of carbonated pulping fluids and precipitated calcium carbonate byproducts in a second centrifuge to separate and discard the calcium carbonate byproducts, thereby producing treated white water for use in the recovery process; and

aa. storing the treated white water in storage tanks for use in the recover process and apparatus.

4. The method according to claim 2, wherein the step of additionally fluffing the cellulosic fibers in a second disk refiner is omitted, and the step of drying includes drying the cellulosic fibers at a temperature between about 250°

F. and 350°

F., thereby producing animal and fowl bedding product.