Patent US3067175A successfully refreshed from Google Patents.
Patent US4416666A successfully refreshed from Google Patents.
US4416666A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal-water slurry and method for its preparation
Assignee: Alfred University Research Foundation Inc
•
Filing: 1981-07-31
•
Granted: 1983-11-22
•
Expires: 2001-07-31
Abstract
Abstract A deashed coal-water slurry and process for preparing the same containing 65-85 percent of solids and 0.01-2.4 weight percent of dispersing agent. The slurry is comprised of a coal compact whose coal particles have a particle size distribution in substantial accordance with a specified formula. The coal-water slurry has a relatively low viscosity of less than 4,000 centipoise at a 75 percent solids content and, when it is pumped at either a constant or an increasing shear rate, its viscosity decreases. Also disclosed are a pumping process and an electrophoretic deashing cell and process.
Inventors
- 👤 James E. Funk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:49
CPC Classifications
C; C21; C21B; C21B5/00; C21B5/001; C21B5/003; C21B5/004; C10; C10L; C10L1/00; C10L1/32; C10L1/326
Claims Analysis
Total Claims: 61
Claim 1
Independent Claim
355 words
A stable deashed coal-water slurry containing from about 65 to about 85 percent of solids by weight of slurry, from about 15 to about 35 percent of carrier water by weight of slurry, from about 0 to about 14 weight percent of ash by weight of solids, and from about 0.01 to about 4.0 weight percent of dispersing agent by weight of dry coal, wherein: (a) said coal-water slurry has a Brookfield viscosity of less than 4,000 centipoise when tested at a solids content of 75 weight percent, ambient temperature, and 60 revolutions per minute; (b) said coal-water slurry has a yield stress of from about 0.1 to about 10 Pascals; (c) the viscosity of said coal-water slurry decreases at a constant shear rate with time, decreases at an increasing shear rate, and decreases at an increasing temperature; (d) said coal-water slurry comprises a compact of finely-divided particles of coal dispersed in said carrier water; (e) at least about 85 weight percent of the particles of coal in said coal-water slurry have a particle size less than 300 microns; (f) no more than 0.5 weight percent of the particles of coal in said slurry have a particle size less than 0.05 microns; (g) from about 5 to about 36 weight percent of the particles of coal in said slurry are of colloidal size, being smaller than about 3 microns, and said colloidal sized particles of coal have a net zeta potential in said coal-water slurry of from about 15 to about 85 millivolts; and (h) said compact of finely divided particles of coal has a particle size distribution substantially in accordance with the following formula: ##EQU6## where CPFT=cumulative weight percent, dry basis, of particles finer than a particle of stated size, D, D=diameter of any particle in the compact, D L =diameter of largest particle in compact, sieve size or its equivalent, being from about 38 to about 400 microns, D S =diameter of smallest particle in compact, being from about 0.01 to about 0.4 microns, and n=numerical exponent, with n being from about 0.2 to about 0.5 and with all diameters sized in microns.
Claim 2
Dependent Claim
355 words
A stable deashed coal-water slurry containing from about 65 to about 85 percent of solids by weight of slurry, from about 15 to about 35 percent of carrier water by weight of slurry, from about 0 to about 14 weight percent of ash by weight of solids, and from about 0.01 to about 4.0 weight percent of dispersing agent by weight of dry coal, wherein: (a) said coal-water slurry has a Brookfield viscosity of less than 4,000 centipoise when tested at a solids content of 75 weight percent, ambient temperature, and 60 revolutions per minute; (b) said coal-water slurry has a yield stress of from about 0.1 to about 10 Pascals; (c) the viscosity of said coal-water slurry decreases at a constant shear rate with time, decreases at an increasing shear rate, and decreases at an increasing temperature; (d) said coal-water slurry comprises a compact of finely-divided particles of coal dispersed in said carrier water; (e) at least about 85 weight percent of the particles of coal in said coal-water slurry have a particle size less than 300 microns; (f) no more than 0.5 weight percent of the particles of coal in said slurry have a particle size less than 0.05 microns; (g) from about 5 to about 36 weight percent of the particles of coal in said slurry are of colloidal size, being smaller than about 3 microns, and said colloidal sized particles of coal have a net zeta potential in said coal-water slurry of from about 15 to about 85 millivolts; and (h) said compact of finely divided particles of coal has a particle size distribution substantially in accordance with the following formula: ##EQU6## where CPFT=cumulative weight percent, dry basis, of particles finer than a particle of stated size, D, D=diameter of any particle in the compact, D L =diameter of largest particle in compact, sieve size or its equivalent, being from about 38 to about 400 microns, D S =diameter of smallest particle in compact, being from about 0.01 to about 0.4 microns, and n=numerical exponent, with n being from about 0.2 to about 0.5 and with all diameters sized in microns.
Claim 3
Dependent Claim
16 words
The coal-water slurry as recited in claim 1 wherein said dispersing agent is an organic surfactant.
Claim 4
Dependent Claim
13 words
The coal-water slurry as recited in claim 2 wherein said surfactant is anionic.
Claim 5
Dependent Claim
21 words
The coal-water slurry as recited in claim 3 wherein the pH of said slurry is from about 5 to about 12.
Claim 6
Dependent Claim
24 words
The coal-water slurry as recited in claim 4 wherein said slurry contains less than about 5 weight percent of ash by weight of solids.
Claim 7
Dependent Claim
165 words
The coal-water slurry as recited in claim 5 wherein: (a) said D S is from about 0.05 to about 0.25 microns, said D L is from about 100 to about 300 microns, and said n is from about 0.27 to about 0.42; (b) said coal-water slurry contains at least about 70 weight percent of solids by weight of slurry; (c) the Brookfield viscosity of said slurry when it is tested at a solids content of 75 weight percent, at 60 revolutions per minute, and at ambient temperature and pressure is less than 3000 centipoise; (d) said slurry has a yield stress of from about 0.5 to about 7 Pascals; (e) at least about 90 weight percent of the coal particles in the slurry have a particle size less than about 300 microns; (f) said colloidal size particles of coal have a zeta potential of from about -30 to about -70 millivolts; and (g) the pH of said slurry is from about 7 to about 11.
Claim 8
Dependent Claim
114 words
The coal-water slurry as recited in claim 6 wherein: (a) said D S is from about 0.05 to about 0.20, said D L is from about 200 to about 250 microns, and said n is from about 0.33 to about 0.37; (b) the Brookfield viscosity of said slurry when it is tested at 75 weight percent of solids, 60 revolutions per minute, and ambient temperature and pressure is from about 300 to about 2400 centipoise; (c) said slurry has a yield stress of from about 0.75 to about 5 Pascals; and (d) at least about 95 weight percent of the coal particles in the slurry have a particle size less than about 300 microns.
Claim 9
Dependent Claim
43 words
The coal-water slurry as recited in claim 7 wherein said D L is about 220 microns and said slurry has a Brookfield viscosity at 75 weight percent solids, 60 revolutions per minute, and ambient temperature and pressure of less than about 2000 centipoise.
Claim 10
Dependent Claim
24 words
The coal-water slurry as recited in claim 1 wherein said slurry contains less than about 5 weight percent of ash by weight of solids.
Claim 11
Dependent Claim
149 words
The coal-water slurry of claim 1 wherein (a) said D S is from about 0.05 to about 0.25 microns, said D L is from about 100 to about 300 microns, and said n is from about 0.27 to about 0.42; (b) said coal-water slurry contains at least about 70 weight percent of solids by weight of slurry; (c) the Brookfield viscosity of said slurry when it is tested at a solids content of 75 weight percent, at 60 revolutions per minute, and at ambient temperature and pressure is less than 3000 centipoise; (d) said slurry has a yield stress of from about 1 to about 7 Pascals; (e) at least about 90 weight percent of the coal particles in the slurry have a particle size less than about 300 microns; (f) said colloidal size particles of coal have a zeta potential of from about -30 to about -70 millivolts.
Claim 12
Dependent Claim
112 words
The coal-water slurry of claim 1 wherein: (a) said D S is from about 0.05 to about 0.20, said D L is from about 200 to about 250 microns, and said n is from about 0.33 to about 0.37; (b) the Brookfield viscosity of said slurry when it is tested at 75 weight percent of solids, 60 revolutions per minute, and ambient temperature and pressure is from about 300 to about 2400 centipoise; (c) said slurry has a yield stress of from about 2 to about 5 Pascals; and (d) at least about 95 weight percent of the coal particles in the slurry have a particle size less than about 300 microns.
Claim 13
Dependent Claim
175 words
A process for preparing a coal-water slurry, comprising the step of grinding a coal-water mixture comprised of from about 65 to about 85 weight percent of solids by weight of slurry, from about 15 to about 35 weight percent of carrier water by weight of slurry, and from about 0.01 to about 4.0 weight percent of dispersing agent by weight of dry coal until said coal-water slurry comprises a compact of finely-divided particles of coal dispersed in said carrier water and said compact has a particle size distribution substantially in accordance with the following formula: ##EQU7## where CPFT=cumulative weight percent, dry basis, of particles finer than a particle of stated size, D, D=diameter of any particle in the compact, D L =diameter of largest particle in compact, sieve size or its equivalent, being from about 38 to about 400 microns, D S =diameter of smallest particle in compact, being from about 0.01 to about 0.4 microns, and n=numerical exponent, with n being from about 0.2 to about 0.5 and with all diameters sized in microns.
Claim 14
Dependent Claim
175 words
A process for preparing a coal-water slurry, comprising the step of grinding a coal-water mixture comprised of from about 65 to about 85 weight percent of solids by weight of slurry, from about 15 to about 35 weight percent of carrier water by weight of slurry, and from about 0.01 to about 4.0 weight percent of dispersing agent by weight of dry coal until said coal-water slurry comprises a compact of finely-divided particles of coal dispersed in said carrier water and said compact has a particle size distribution substantially in accordance with the following formula: ##EQU7## where CPFT=cumulative weight percent, dry basis, of particles finer than a particle of stated size, D, D=diameter of any particle in the compact, D L =diameter of largest particle in compact, sieve size or its equivalent, being from about 38 to about 400 microns, D S =diameter of smallest particle in compact, being from about 0.01 to about 0.4 microns, and n=numerical exponent, with n being from about 0.2 to about 0.5 and with all diameters sized in microns.
Claim 15
Dependent Claim
21 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 0 to 13 weight percent of ash.
Claim 16
Dependent Claim
21 words
The process as recited in claim 13, wherein said coal-water mixture comprises from about 0 to 10 weight percent of ash.
Claim 17
Dependent Claim
21 words
The process as recited in claim 13, wherein said coal-water mixture comprises from about 0 to 5 weight percent of ash.
Claim 18
Dependent Claim
27 words
The process as recited in claim 12, wherein said coal-water mixture comprises at least about 70 weight percent of said solids, as measured on a dry basis.
Claim 19
Dependent Claim
23 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 20 to about 35 weight percent of carrier water.
Claim 20
Dependent Claim
23 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 15 to about 25 weight percent of carrier water.
Claim 21
Dependent Claim
23 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 0.01 to about 4.0 weight percent of organic surfactant.
Claim 22
Dependent Claim
14 words
The process as recited in claim 19, wherein said surfactant is anionic organic surfactant.
Claim 23
Dependent Claim
24 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 0.01 to about 2.4 weight percent of said dispersing agent.
Claim 24
Dependent Claim
24 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 0.03 to about 1.8 weight percent of said dispersing agent.
Claim 25
Dependent Claim
24 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 0.05 to about 1.4 weight percent of said dispersing agent.
Claim 26
Dependent Claim
24 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 0.1 to about 1.2 weight percent of said dispersing agent.
Claim 27
Dependent Claim
21 words
The process as recited in claim 12, wherein the pH of said coal-water mixture is from about 5 to about 12.
Claim 28
Dependent Claim
21 words
The process as recited in claim 25, wherein the pH of said coal-water mixture is from about 7 to about 11.
Claim 29
Dependent Claim
22 words
The process as recited in claim 12, wherein said coal-water mixture is comprised of a blend of at least two coal consists.
Claim 30
Dependent Claim
17 words
The process as recited in claim 12, wherein said coal-water mixture is ground in a ball mill.
Claim 31
Dependent Claim
23 words
The process as recited in claim 12, wherein said coal-water mixture comprises from about 0.05 to about 2.0 weight percent of inorganic electrolyte.
Claim 32
Dependent Claim
70 words
The process as recited in claim 29, wherein said inorganic electrolyte is of the formula M.sub.a Z.sub.b wherein M is an alkali metal selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, and francium; Z is an anion selected from the group consisting of hexametaphosphate, pyrophosphate, silicate, sulfate, carbonate, hydroxide, and halide anions; a is the valence of anion Z; and b is the valence of metal M.
Claim 33
Dependent Claim
23 words
The process as recited in claim 29, wherein said coal-water mixture comprises from about 0.1 to about 0.8 weight percent of inorganic electrolyte.
Claim 34
Dependent Claim
23 words
The process as recited in claim 29, wherein said coal-water mixture comprises from about 0.1 to about 0.5 weight percent of inorganic electrolyte.
Claim 35
Dependent Claim
36 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry which comprises at least about 5 weight percent of colloidal coal particles smaller than about 3 microns is produced.
Claim 36
Dependent Claim
37 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry which comprises from about 5 to about 36 weight percent of coal particles smaller than about 3 microns is produced.
Claim 37
Dependent Claim
37 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry which comprises from about 5 to about 20 weight percent of coal particles smaller than about 3 microns is produced.
Claim 38
Dependent Claim
37 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry which comprises from about 7 to about 36 weight percent of coal particles smaller than about 3 microns is produced.
Claim 39
Dependent Claim
46 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry is produced which has a Brookfield viscosity of less than 4,000 centipoise when tested at a solids content of 75 weight percent, ambient temperature, and 60 revolutions per minute.
Claim 40
Dependent Claim
47 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry is produced which has a Brookfield viscosity of less than about 3,000 centipoise when tested at a solids content of 75 weight percent, ambient temperature, and 60 revolutions per minute.
Claim 41
Dependent Claim
49 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry is produced which has a Brookfield viscosity of from about 300 to about 2,400 centipoise when tested at a solids content of 75 weight percent, ambient temperature, and 60 revolutions per minute.
Claim 42
Dependent Claim
40 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry is produced wherein at least 85 weight percent of the coal particles in said slurry have a particle size less than 300 microns.
Claim 43
Dependent Claim
40 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry is produced wherein at least 90 weight percent of the coal particles in said slurry have a particle size less than 300 microns.
Claim 44
Dependent Claim
39 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slury is produced wherein at least 95 percent of the coal particles in said slurry have a particle size less than 300 microns.
Claim 45
Dependent Claim
38 words
The process as recited in claim 12, wherein said coal-water mixture is ground until a coal-water slurry is produced wherein at least about 98 weight percent of the coal particles in said slurry are smaller than 300 microns.
Claim 46
Dependent Claim
34 words
The process as recited in claim 25, wherein said coal-water mixture is ground until a coal-water slurry which comprises at least 5 weight percent of coal particles smaller than about 3 microns is produced.
Claim 47
Dependent Claim
37 words
The process as recited in claim 44, wherein said coal-water slurry has a Brookfield viscosity of less than 4,000 centipoise when tested at a solids content of 27 weight percent, ambient temperature, and 60 revolutions per minute.
Claim 48
Dependent Claim
23 words
The process as recited in claim 45, wherein said coal-water mixture comprises from about 0.01 to about 2.4 weight percent of dispersing agent.
Claim 49
Dependent Claim
15 words
The process as recited in claim 46, wherein said dispersing agent is anionic organic surfactant.
Claim 50
Dependent Claim
40 words
The process as recited in claim 46, wherein said coal-water mixture is ground until a coal-water slurry is produced wherein at least 85 weight percent of the coal particles in the slurry have a particle size less than 300 microns.
Claim 51
Dependent Claim
27 words
The process as recited in claim 48, wherein said coal-water mixture comprises at least about 70 weight percent of said solids, as measured on a dry basis.
Claim 52
Dependent Claim
21 words
The process as recited in claim 49, wherein said coal-water mixture comprises from about 0 to 5 weight percent of ash.
Claim 53
Dependent Claim
24 words
The process as recited in claim 49, wherein said coal-water mixture comprises from about 0.05 to about 1.4 weight percent of anionic organic surfactant.
Claim 54
Dependent Claim
22 words
The process as recited in claim 49, wherein said coal-water mixture is comprised of a blend of at least two coal consists.
Claim 55
Dependent Claim
17 words
The process as recited in claim 49, wherein said coal-water mixture is ground in a ball mill.
Claim 56
Dependent Claim
23 words
The process as recited in claim 49, wherein said coal-water mixture comprises from about 0.05 to about 2.0 weight percent of inorganic electrolyte.
Claim 57
Dependent Claim
47 words
The process as recited in claim 49, wherein said coal-water mixture is ground until a coal-water slurry is produced which has a Brookfield viscosity of less than about 3,000 centipoise when tested at a solids content of 75 weight percent, ambient temperature, and 60 revolutions per minute.
Claim 58
Dependent Claim
21 words
The process as recited in claim 49, wherein the pH of said coal-water mixture is from about 7 to about 11.
Claim 59
Dependent Claim
23 words
The process as recited in claim 49, wherein said coal-water mixture comprises from about 0.1 to about 0.5 weight percent of inorganic electrolyte.
Claim 60
Dependent Claim
40 words
The process as recited in claim 49, wherein said coal-water mixture is ground until a coal-water slurry is produced wherein at least 95 weight percent of the coal particles in said slurry have a particle size less than 300 microns.
Claim 61
Dependent Claim
49 words
The process as recited in claim 58, wherein said coal-water mixture is ground until a coal-water slurry is produced which has a Brookfield viscosity of from about 300 to about 2400 centipoise when tested at a solids content of 75 weight percent, ambient temperature, and 60 revolutions per minute.
References Cited (Backward Citations)
US4104035A
Cited
US4282006A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-11-21 | 1987-05-23 | 1987-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-21 | 1991-05-23 | 1991-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-21 | 1995-05-23 | 1995-11-22 | $7700.00 | Window Closed / Lapsed |