Water free pulp from pulp slurry

Abstract

By providing a pulp slurry, containing ink and water, and subjecting the slurry to dewatering to produce pulp sludge containing water is formed and a liquid, primarily water, is obtained. Pulp sludge, removed from dewatering is subjected to pressing to produce pressed pulp and expelled water. The expelled water and liquid, primarily water, is combined and recycled to an apparatus to create additional pulp slurry. Dewatered pressed pulp is subjected to dehydration, to transfer water contained within pulp, to air. Pulp resulting from dehydration is then subject to bailing. Furthermore pulp is excluded from a deinking procedure to permit ink to remain within the pulp. Whereby this invention removes water from a pulp slurry and provides pulp substantially devoid of water.

Description

BACKGROUND OF THE INVENTION

[0001] A state of the art process for pulping waste paper and deinking employing a hydrapulper to produce a pulp slurry is described within in U.S. Pat. No. 5,512,133. Processes for deinking is described, for example, within in U.S. Pat. Nos. 3,962,560, 4,311,552, 5,073,234 in which solvents are utilized to separate ink from pulp. A method to separate plastics from municipal solid waste is described by U.S. Pat. No. 5,297,742, and by U.S. Pat. No. 4,160,722. These patents depend on dissimilar, density of plastics and a pulp slurry for separation. U.S. Pat. No. 3,991,60, discloses a method of bailing dewatered, dried pulp and wrapping the resulting bale with protective wire or strip.

[0002] This invention relates to a method of subjecting a slurry of pulp to dewatering to form pulp sludge and liquid, primarily water.

[0003] Therefore, an object of this invention is to obviate many of the limitations and disadvantages of the prior art to form pulp from waste cellulose solids.

[0004] A significant object of this invention is to produce pulp significantly free of water from waste cellulose solids.

[0005] A secondary object of this invention is press pulp to reduce water within pulp and create expelled water.

[0006] An additional object of this invention is to recycle combined expelled water and liquid, primarily water, to form a combination for creation of additional pulp slurry within a pulping apparatus.

[0007] Another object of this invention is significant dehydration of pulp.

[0008] Yet another object of this invention is to subject the dehydrated pulp to bale formation.

[0009] Still another object of this invention is excluding pulp from a deinking procedure to aid production of ink within pulp.

[0010] With the above and other objects in view, this invention relates to the novel features and alternatives and combinations presently described in the brief description of the invention.

Phraseology Applied in the Invention

[0011] Waste paper is with water, pulped by an apparatus for pulping, commonly termed a hydrapulper, to produce a slurry of pulp. A hydrapulper is described within “hydrapulper”, located on the internet, 2002, page 1, which pulps waste paper, with water, into small pieces, to create a pulp slurry resembling “porridge”. The hydrapulper is fitted wit special devises for removing matter such as wire, plastic, paper clips, staples etc. The slurry of pulp, produced by waste paper, is then subjected to dewatering to form a discharge of pulp sludge containing water and a liquid, primarily water, is obtained. Filtering is one such dewatering means as described by Brown, et al., within Unit Operations, 1950, page 229 and page 241. Pulp sludge, removed from dewatering, is subjected to pressing to produce expelled water and pressed pulp moist with water. The expelled water is combined with liquid containing water (and ink) to form additional pulp slurry.

[0012] Expelled water and liquid containing water may contain unfiltered pulp. Pulp, moist with water, is subjected to dehydration to transfer water from pulp to air. Pulp, defined by this method, substantially free of water, is subjected to bale formation to produce bales of pulp. Bales of pulp are transported to a destination for planned utilization. Bales of pulp, after reduction in size, become fibers of cellulose, and are then subjected to gasification for utilization within fuel cells to generate electricity from the energy of the pulp. Accordingly waste paper contained within municipal solid waste (MSW) can be pulped to create a slurry of pulp. Without using deinking procedures within this method, production of pulp, essentially free of water, involuntarily embodies ink.

[0013] Frequently a deinking procedure accompanies or precedes pulping. This procedure is described within Handbook Of Pulp And Paper Technology, Second Edition, 1970, Edited by Britt, pages 80-83. Deinked slurry of insoluble pulp is removed from the hydrapulper and is usually de-watered and dried to produce dried pulp. The pulp, excluded from a deinking procedure, will acquire ink within pulp. The deinking procedure is accordingly needless within the outlined method but is referred to for information only.

BRIEF DESCRIPTION OF THE INVENTION

[0014] The present invention, in its broadest aspect, is a method to produce pulp from an aqueous pulp slurry which comprises: providing a pulp slurry, containing ink and water, and dewatering means, and subjecting the pulp slurry to dewatering to form pulp sludge and a liquid, primarily water. Upon removing the pulp sludge and the liquid from the dewatering means, and subjecting the pulp sludge to dehydration, to transfer water within the pulp sludge, to form pulp substantially devoid of water. Pulp furthermore is excluded from a needless deinking procedure to involuntarily embody ink within the pulp. After creating additional pulp slurry from the liquid, primarily water, whereby a pulp slurry is derived from a liquid, primarily water, to create pulp substantially devoid of water.

[0015] Key features of this invention are:

[0016] Pulp, commonly contains ink, and is accepted within the pulp, so that deinking is unnecessary.

[0017] A pulp slurry is produced by waste paper in an apparatus for pulping.

[0018] Upon subjecting pulp sludge to pressing, pressed pulp results and expelled water is created.

[0019] The pressed pulp transfers contained water to air to form pulp, substantially devoid of water.

[0020] Pressed pulp is subject to dehydration by a drier.

[0021] Pulp, substantially free of water, is subjected to bale formation to form bales of pulp.

[0022] Baled pulp, after breaking and reduction in size, is subjected to gasification to provide energy to power fuel cells.

[0023] Liquid, containing water, is recycled to an apparatus for pulping for additional production of a pulp slurry containing ink and water.

[0024] The method can be accomplished in batch form, continuous form, as well as by a combined form.

[0025] Pulp slurry, formed within a hydapulper, or similar device, is separated from matter subject to pulping but unaffected by pulping.

[0026] The pulp slurry contains water and organic compounds.

[0027] By supplying waste paper within a hydapulper, or similar device, a pulp slurry is created

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The features that are considered characteristic of this invention are set forth in the appended claims. This invention, however, both as to its origination and method of operations as well as additional advantages will best be understood from the following description when read in conjunction with the accompanying drawings in which:

[0029] FIG. 1 is a flow sheet denoting the invention as set forth in the appended claims.

[0030] FIG. 2 is a flow sheet representing a method for gasification of pulp to apply resulting gas to power fuel cells.

[0031] FIG. 3 is a flow sheet illustrative of a method to produce a pulp slurry.

[0032] FIG. 4 is a flow sheet illustrative of a method to produce a pulp sludge and a filtrate.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0033] The flow diagram of FIG. 1 illustrates the preferred embodiment of the present invention. In the diagram, rectangles represent stages or functions of the present invention and unnecessarily separate components. Arrows indicate direction of flow of material in the method.

[0034] Referring to FIG. 1, pulp slurry containing ink and water 10, accordingly pulp, containing cellulose, is conveyed to pulp dewatering stage 12, to create liquid, primarily water 14, and produce pulp sludge 16 which is transferred to pulp pressing stage 18 to create pressed pulp 22 and expelled water 20. Pressed pulp 22 is conveyed to pulp dehydration stage 24 where air 26 transfers water from pressed pulp to create dried pulp 28 and humid air 26A. Dried pulp 28 is conveyed to bale formation stage 30, to be baled and strapped by strapping 32 to create strapped bales 34. As a result dried pulp 28 is baled and strapped for protection. Pulp slurry containing ink and water 10 is sometimes produced from waste paper contained within municipal solid waste, utilizing an apparatus for creation of a pulp slurry. Waste paper for forming pulp slurry containing ink and water 10, is frequently selected from the group of newspaper, cardboard, office papers and municipal solid waste including an individual or a combination thereof A variety of substances contained within municipal solid waste is separated from matter subject to pulping but unaffected by pulping. Pulp, furthermore is excluded from a deinking procedure, so that ink remaining within the pulp is appropriate. Liquid 14, primarily water, commonly contains pulp of decreased size.

[0035] Referring to FIG. 2, strapped bales 34, are conveyed to pulp bale breaking stage 36, to provide removed strapping 36A and produce fibrous pulp 38 for transfer to gasification stage 40 to react with steam 42 to produce gas 44. Gas 44 is conveyed to fuel cells 46 to generate direct current 50 from air 48 which is used to satisfy oxygen requirements and then discards purge 48A. The method as described generally depend on fuel cells selected from the group consisting of molten carbonate fuel cells, solid oxide fuel cells or a combination thereof. Customarily the fuel cells are stationary within a site. The intention of producing fibrous pulp 38 is to create pulp with a reduction in size. Commonly, strapped bales of pulp 34, are transported and stored prior to subjection to pulp bale breaking stage 36.

[0036] Referring to FIG. 3, waste paper 10A, is conveyed to pulping apparatus 52 and pulped by 14A. 14A is a combination of liquid, primarily water, 14 and expelled water 20 to produce pulp slurry, containing ink and water 10. Waste paper 10A is sometimes obtained from waste paper contained within municipal solid waste. Generally the method is stationary within a site.

[0037] Referring to FIG. 4, pulp slurry, containing ink and water, 10, is conveyed to filter media stage 54, to create pulp sludge 16 and filtrate 14A. Filter media stage 54, is commonly equipped with filtering media or membranes.

Claims

1. A method to separate pulp from an aqueous pulp slurry, which comprises: providing a pulp slurry containing ink and water, and providing dewatering means, and subjecting said pulp slurry to said dewatering means to form pulp sludge and a liquid primarily water, and removing said pulp sludge and said liquid from said dewatering means, and subjecting said pulp sludge to dehydration to transfer water within the pulp sludge to form pulp substantially devoid of water, and creating additional pulp slurry containing ink and water from said liquid whereby this invention removes water from a pulp slurry and provides pulp substantially devoid of water.

2. The method as described in claim 1 wherein said pulp slurry is obtained from waste paper.

3. The method as described in claim 2 wherein the pulp slurry contains ink from waste paper.

4. The method as described in claim 2 wherein the waste paper is selected from the group of, newspapers, office papers and cardboard including an individual or a combination thereof.

5. The method as described in claim 1 wherein said pulp, substantially devoid of water, is subjected to bailing to form bales of pulp.

6. The method as described in claim 1 wherein said pulp slurry is produced from waste paper within an apparatus for pulping.

7. The method as described in claim 1 wherein said pulp, substantially devoid of water, is subjected to gasification.

8. The method as described in claim 7 wherein gasification from the pulp is used to power fuel cells.

9. The method as described in claim 8 wherein the fuel cells are selected from the group consisting of molten carbonate fuel cells, solid oxide fuel cells or a combination thereof.

10. The method as described in claim 8 wherein the fuel cells are stationary within a site.

11. The method as described in claim 1 wherein said pulp slurry is produced from cellulose solids.

12. The method as described in claim 1 wherein said pulp slurry is separated from matter unaffected by pulping.

13. The method as described in claim 1 wherein said pulp is obtained from waste paper contained within municipal solid waste.

14. The method as described in claim 1 wherein said method is accomplished in batch form as well as by a continuous form.

15. The method as described in claim 1 wherein said pulp sludge is subject to dehydration by air.

16. The method as described in claim 1 wherein said pulp sludge is subject to dehydration by a drier.

17. The method as described in claim 1 wherein said pulp slurry is produced from an apparatus to create additional pulp slurry.

18. The method as described in claim 1 wherein said pulp slurry contains organic compounds.

19. The method as described in claim 1 wherein said dewatering means is a filter to produce filtered pulp and an aqueous filtrate.

20. The method as described in claim 1 wherein said dewatering means is a filter press to produce pressed pulp and an expelled liquid, primarily water.