US5040734A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for determining physical properties
Assignee: BP PLC
•
Filing: 1990-02-28
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Granted: 1991-08-20
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Expires: 2010-02-28
Abstract
Abstract A method for the determination of the value of a property of the material within a mill during the comminution of solid material within the mill comprises the steps of: (a) detecting the noise intensity of milling by means of an analog electrical signal, the intensity of which is proportional to the intensity of the noise in the audio frequency range, (b) converting the analog signal to a digital signal, (c) passing the digital signal through a digital band-pass filter to select at least two frequency bands, and (d) analyzing the data from the bands by means of a multivariate statistical technique to obtain the value of the property. The method is particularly suitable for determining the particle size distribution of material being ground in a ball mill.
Inventors
- 👤 Ronald M. Belchamber
- 👤 Patrick Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:27
CPC Classifications
B; B02; B02C; B02C25/00; G; G01; G01N; G01N29/00; G01N29/04; G01N29/045; G01N29/046; G01N2291/00; G01N2291/02; G01N2291/024; G01N2291/02408
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
152 words
A non-intrusive method for determining a number of inter-related values of physical properties of material within a mill during comminution of the material within the mill wherein the method comprises the steps of: (a) detecting an acoustic frequency distribution of milling, in the audio frequency range by utilizing a sound transducer, providing output from said transducer as an analogue electrical signal, the intensity of signal is proportional to the intensity of audio frequency range sound, (b) converting the analogue signal to a digital signal, (c) passing the digital signal through a digital band-pass filter and selecting at least two frequency bands from the audio frequency range of said digital signal passing through said band-pass filter, (d) averaging power in each of the bands for a specified period of time, and (e) analysing the averaged power in the bands by utilizing a multivariate statistical technique, thereby obtaining the values of the physical properties.
Claim 2
Dependent Claim
152 words
A non-intrusive method for determining a number of inter-related values of physical properties of material within a mill during comminution of the material within the mill wherein the method comprises the steps of: (a) detecting an acoustic frequency distribution of milling, in the audio frequency range by utilizing a sound transducer, providing output from said transducer as an analogue electrical signal, the intensity of signal is proportional to the intensity of audio frequency range sound, (b) converting the analogue signal to a digital signal, (c) passing the digital signal through a digital band-pass filter and selecting at least two frequency bands from the audio frequency range of said digital signal passing through said band-pass filter, (d) averaging power in each of the bands for a specified period of time, and (e) analysing the averaged power in the bands by utilizing a multivariate statistical technique, thereby obtaining the values of the physical properties.
Claim 3
Dependent Claim
13 words
The method according to claim 1 wherein the sound transducer is a microphone.
Claim 4
Dependent Claim
31 words
The method according to claim 1 where the properties are selected from the group consisting of particle size distribution of solid particles, pulp density being milled and pulp volume during milling.
Claim 5
Dependent Claim
12 words
The method according the claim 1 including amplifying the analogue electrical signal.
Claim 6
Dependent Claim
16 words
The method according to claim 1 including passing the analogue electrical signal through a band-pass filter.
Claim 7
Dependent Claim
26 words
The method according to claim 5 including removing frequencies above 10 KHz from the audio frequency range of said digital signal passing through said band-pass filter.
Claim 8
Dependent Claim
26 words
The method according to claim 5 including removing frequencies below 50 Hz from the audio frequency range of said digital signal passing through said band-pass filter.
Claim 9
Dependent Claim
21 words
The method according to claim 5 wherein the band-pass filter is capable of selecting from 2 to 24 desired frequency bands.
Claim 10
Dependent Claim
18 words
The method according to claim 1 wherein the multivariate statistical technique is a method of principal components analysis.
Claim 11
Dependent Claim
18 words
The method according to claim 1 wherein the multivariate statistical technique is a method of partial least squares.
Claim 12
Dependent Claim
11 words
The method according to claim 1 including performing each step on-line.
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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) | 1994-08-19 | 1995-02-18 | 1995-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-19 | 1999-02-18 | 1999-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-19 | 2003-02-18 | 2003-08-20 | $7700.00 | Window Closed / Lapsed |