US4175158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Agglomerating particulate perlite
Assignee: Individual
•
Filing: 1977-10-17
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Granted: 1979-11-20
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Expires: 1997-10-17
Abstract
Abstract Particulate perlite fines are agglomerated to increase the apparent particle size by forming a mixture of the perlite fines with a compound such as boric acid capable of being substantially converted to B 2 O 3 at elevated temperatures. The mixture is heated while mixing to convert the compound to B 2 O 3 and to at least partially coat the particulate perlite.The mixture is then heated above the melting point of B 2 O 3 to agglomerate the perlite fines. The product of this process has particular utility as an improved filter aid.
Inventors
- 👤 Elerington Saunders
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:37
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; B01J20/106; B01D; B01D37/00; B01D37/02; C; C04; C04B; C04B18/00; C04B18/02; C04B18/023; Y; Y10; Y10S; Y10S106/00; Y10S106/02; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2993; Y10T428/2996
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
127 words
A method of forming a particulate product consisting essentially of agglomerated particulate perlite fines, said method comprising the steps of: (a) commingling said perlite fines with a boron compound to form a particulate mixture with said boron compound, said boron compound capable of being substantially converted to B 2 O 3 at elevated temperatures; (b) initially heating said particulate mixture sufficiently to coat said perlite fines at least partially with said boron compound while continuously mixing said particulate mixture; (c) converting said boron compound to B 2 O 3 ; and (d) diffusing said B 2 O 3 into said perlite by additional heating of said particulate mixture; said steps resulting in the formation of a plurality of particles, said particles being larger than said perlite fines.
Claim 2
Independent Claim
127 words
A method of forming a particulate product consisting essentially of agglomerated particulate perlite fines, said method comprising the steps of: (a) commingling said perlite fines with a boron compound to form a particulate mixture with said boron compound, said boron compound capable of being substantially converted to B 2 O 3 at elevated temperatures; (b) initially heating said particulate mixture sufficiently to coat said perlite fines at least partially with said boron compound while continuously mixing said particulate mixture; (c) converting said boron compound to B 2 O 3 ; and (d) diffusing said B 2 O 3 into said perlite by additional heating of said particulate mixture; said steps resulting in the formation of a plurality of particles, said particles being larger than said perlite fines.
Claim 3
Dependent Claim
33 words
The method of claim 1 wherein said B 2 O 3 is diffused into said perlite by heating said particulate mixture to a temperature in the range of from 1400° to 1800° F.
Claim 4
Dependent Claim
17 words
The method of claim 1 wherein said boron compound is a solid particulate material at room temperature.
Claim 5
Dependent Claim
16 words
The method of claim 3 wherein said solid particulate compound is H 3 BO 3 .
Claim 6
Dependent Claim
39 words
The method of claim 4 wherein said initial heating of said particulate mixture is conducted at a temperature in the range of from 365° to 600° F. for a time in the range of from 1 to 10 minutes.
Claim 7
Dependent Claim
20 words
The method of claim 3 wherein said boron compound comprises from 1 to 10 weight percent of said particulate mixture.
Claim 8
Dependent Claim
24 words
The method of claim 3 wheein said boron compound is a solid powder comprising from 3 to 5 weight percent of said particulate mixture.
Claim 9
Dependent Claim
24 words
The method of claim 7 wherein said boron compound is H 3 BO 3 and has a size less than -325 U.S. Standard mesh.
Claim 10
Independent Claim
128 words
A method of forming a particulate filter aid by agglomerating particulate perlite fines having an initial mean particle size of less than 30 microns comprising the steps of: (a) commingling said perlite fines with particulate solid H 3 BO 3 to form a particulate mixture of approximately 5 weight percent H 3 BO 3 , said H 3 BO 3 having a particle size of less than -325 U.S. Standard mesh; (b) initially heating said particulate mixture above 365° F. for at least one minute while mixing said particulate mixture; and (c) heating said particulate mixture to a temperature of at least 1200° F. for at least one hour, said steps resulting in the formation of a plurality of particles, said particles being larger than said perlite fines.
Claim 11
Independent Claim
128 words
A method of forming a particulate filter aid by agglomerating particulate perlite fines having an initial mean particle size of less than 30 microns comprising the steps of: (a) commingling said perlite fines with particulate solid H 3 BO 3 to form a particulate mixture of approximately 5 weight percent H 3 BO 3 , said H 3 BO 3 having a particle size of less than -325 U.S. Standard mesh; (b) initially heating said particulate mixture above 365° F. for at least one minute while mixing said particulate mixture; and (c) heating said particulate mixture to a temperature of at least 1200° F. for at least one hour, said steps resulting in the formation of a plurality of particles, said particles being larger than said perlite fines.
Claim 12
Dependent Claim
23 words
The method of claim 9 wherein step C is carried out at a temperature in the range of from 1400° to 1800° F.
Claim 13
Dependent Claim
20 words
The method of claim 9 in which said particulate perlite has an initial mean particle size of about 4 microns.
Claim 14
Dependent Claim
36 words
A particulate agglomerate of perlite and B 2 O 3 having an apparent particle size of from 16 to 20 microns produced by the agglomeration of smaller perlite particles according to the method of claim 1.
Claim 15
Dependent Claim
85 words
A particulate agglomerate consisting essentially of perlite particles, said agglomerate being formed from fine particulate perlite and produced by initially coating said fine particulate perlite with molten H 3 BO 3 while mixing said perlite and said H 3 BO 3 to form a particulate mixture, subsequently converting said H 3 BO 3 to B 2 O 3 by heat treatment; and finally, diffusing said B 2 O 3 into said perlite by heating said particulate mixture to a temperature of at least 1200° F.
Claim 16
Dependent Claim
85 words
A particulate agglomerate consisting essentially of perlite particles, said agglomerate being formed from fine particulate perlite and produced by initially coating said fine particulate perlite with molten H 3 BO 3 while mixing said perlite and said H 3 BO 3 to form a particulate mixture, subsequently converting said H 3 BO 3 to B 2 O 3 by heat treatment; and finally, diffusing said B 2 O 3 into said perlite by heating said particulate mixture to a temperature of at least 1200° F.
Claim 17
Dependent Claim
65 words
A filter aid consisting essentially of a plurality of perlite agglomerates, said agglomerates having a mean size in excess of 20 microns, said agglomerates being comprised of a plurality of perlite particles having a mean particle size of approximately 5 microns bonded together with B 2 O 3 , to form said agglomerates, said B 2 O 3 being insolubilized by diffusion into said perlite.
Claim 18
Dependent Claim
65 words
A filter aid consisting essentially of a plurality of perlite agglomerates, said agglomerates having a mean size in excess of 20 microns, said agglomerates being comprised of a plurality of perlite particles having a mean particle size of approximately 5 microns bonded together with B 2 O 3 , to form said agglomerates, said B 2 O 3 being insolubilized by diffusion into said perlite.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-11-19 | 1983-05-21 | 1983-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-19 | 1987-05-21 | 1987-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-19 | 1991-05-21 | 1991-11-20 | $7700.00 | Window Closed / Lapsed |