US3908465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Particle size analyzer
Assignee: Leland Stanford Junior University
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Filing: 1974-02-25
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Granted: 1975-09-30
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Expires: 1994-02-25
Abstract
Abstract Method and apparatus are provided for a simple onstream particle size analysis. The device can be a single or multiple channel device. The percent solids is continuously measured both in a sample stream and in an internal reference stream, containing particles below a predetermined size. A semi-permeable hydraulic system is used such that the particle mass concentration in the internal reference stream can vary and remain proportional to the particle mass concentration of particles below the predetermined size in the sample stream. The apparatus provides a compartment having two cells separated by a perforated barrier and means for measuring the pulp density of the slurries in each of the cells.
Inventors
- 👤 Robert W Bartlett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:05
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/02; G01N15/0272
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
131 words
A method for analyzing a slurry stream, having particles of varying size, for particles below a predetermined size which comprises: directing a first sample slurry stream having particles iN a range of sizes past and in contact with a perforated barrier having openings of a size intermediate the size range of said particles in said first slurry stream; directing a second reference slurry stream past and in contact with the opposite side of said perforated barrier having particles of a size at and below the openings in said perforated barrier; measuring the pulp density of said first and second slurry streams; and determining the mass fraction of particles at and below said predetermined size in said first slurry stream from the pulp density determinations of said first and second slurry streams.
Claim 2
Independent Claim
131 words
A method for analyzing a slurry stream, having particles of varying size, for particles below a predetermined size which comprises: directing a first sample slurry stream having particles iN a range of sizes past and in contact with a perforated barrier having openings of a size intermediate the size range of said particles in said first slurry stream; directing a second reference slurry stream past and in contact with the opposite side of said perforated barrier having particles of a size at and below the openings in said perforated barrier; measuring the pulp density of said first and second slurry streams; and determining the mass fraction of particles at and below said predetermined size in said first slurry stream from the pulp density determinations of said first and second slurry streams.
Claim 3
Dependent Claim
18 words
A method according to claim 1, wherein said first stream has less than about 60 weight percent solids.
Claim 4
Dependent Claim
17 words
A method according to claim 1, wherein said first stream is derived from the grinding of ore.
Claim 5
Dependent Claim
20 words
A method according to claim 1, wherein said openings in said perforated barrier are not greater than about 40 mesh.
Claim 6
Dependent Claim
75 words
A particle analyzer comprising: a compartment having first and second cells for containing a sample slurry and a reference slurry respectively, and a perforated barrier having openings of predetermined size between said cells through which said cells communicate; inlet and discharge ports in said first cell; means for agitation of said slurry in cooperative engagement with said second cell; and means for measuring the pulp density of said slurries in said first and second cells.
Claim 7
Dependent Claim
75 words
A particle analyzer comprising: a compartment having first and second cells for containing a sample slurry and a reference slurry respectively, and a perforated barrier having openings of predetermined size between said cells through which said cells communicate; inlet and discharge ports in said first cell; means for agitation of said slurry in cooperative engagement with said second cell; and means for measuring the pulp density of said slurries in said first and second cells.
Claim 8
Dependent Claim
18 words
A particle analyzer according to claim 5, wherein said measuring means are first and second nuclear density gauges.
Claim 9
Dependent Claim
24 words
A particle analyzer according to claim 6, wherein said first and second nuclear density gauges are mounted on said first and second cells respectively.
Claim 10
Dependent Claim
90 words
A particle analyzer according to claim 5, having in addition: a first conduit in a fluid receiving relationship with said discharge port of said first cell and having a sigmoidal region; inlet and discharge ports in said second cell; a second conduit connecting said inlet and discharge ports of said second cell having a sigmoidal region; pump means for circulating said reference slurry through said second cell and said second conduit; and wherein said measuring means is in operative relationship with said sigmoidal regions of said first and second conduits.
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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) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |