US4531093A
Expired / Lapsed
US
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Method and apparatus for coal analysis and flow measurement
Assignee: Southwest Research Institute
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Filing: 1983-05-05
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Granted: 1985-07-23
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Expires: 2003-05-05
Abstract
Abstract A flow meter apparatus and method for measuring the flow, composition and heat content of coal is set forth. In the preferred and illustrated embodiment, the free or unpaired electron population of flowing coal is measured by electron magnetic resonance (EMR); the hydrogen nucleii population is measured by nuclear magnetic resonance (NMR). By calibration utilizing a standard specimen for a given type of coal, a profile for various types of coal can be obtained wherein measurement data is converted into an indication of the heat content typically measured in BTU per pound. This enables provision of a volumetric flow meter, a flow meter indicating flow in calorie content. This device enables integration to provide total heat content flow. Other variables describing the coal can be obtained.
Inventors
- 👤 William L. Rollwitz
- 👤 James D. King
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:22
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01F; G01F1/00; G01F1/704; G01F1/708; G01F1/716; G01F1/74; G01R33/60
Claims Analysis
Total Claims: 50
Claim 1
Independent Claim
79 words
A method of measuring the heat content of coal comprising the steps of: (a) measuring the nuclear magnetic resonance (NMR) response of hydrogen in the coal; (b) measuring the electron magnetic resonance (EMR) of free electrons in the coal; and (c) determining the heat content of the coal as a function of the hydrogen NMR and the EMR measurements wherein the step of determining includes the step of comparing with a standard value derived from a known coal assay.
Claim 2
Independent Claim
79 words
A method of measuring the heat content of coal comprising the steps of: (a) measuring the nuclear magnetic resonance (NMR) response of hydrogen in the coal; (b) measuring the electron magnetic resonance (EMR) of free electrons in the coal; and (c) determining the heat content of the coal as a function of the hydrogen NMR and the EMR measurements wherein the step of determining includes the step of comparing with a standard value derived from a known coal assay.
Claim 3
Dependent Claim
58 words
The method of claim 1 wherein the step of determining the heat content includes the steps of comparing the measured values of hydrogen in the coal with values dependent on the type of coal and determining the heat content in proportion to the value dependent on the type of coal, which value is from the known coal assay.
Claim 4
Dependent Claim
24 words
The method of claim 1 including the step of repetitively obtaining measurements from continuously flowing coal passing through a magnetic field of specified intensity.
Claim 5
Dependent Claim
19 words
The method of claim 1 including the step of impressing first and second separate magnetic fields on the coal.
Claim 6
Dependent Claim
56 words
The method of claim 1 including the step of forming a magnetic field of specified intensity on the coal, and then interrogating the coal with an RF field; detecting a RF signal from the coal in the magnetic field and the RF field; and obtaining an output from the detected RF signal encoding a measurement therein.
Claim 7
Dependent Claim
27 words
The method of claim 5 wherein free electrons from the coal form the RF signal detected and the signal encodes free electron population in an output signal.
Claim 8
Dependent Claim
27 words
The method of claim 6 including the step of converting the output signal by multiplying the resonance line width by amplitude and then taking the product thereof.
Claim 9
Dependent Claim
46 words
The method of claim 1 wherein the heat content is given by D=AH+(BC)+D where D=heat content H=the amplitude of NMR signal from hydrogen in the coal; C=the EMR signal amplitude times resonance line width of the EMR signal from the coal; and A, B and D=constants.
Claim 10
Dependent Claim
27 words
The method of claim 1 wherein the step of measuring related to hydrogen includes measuring the free induction decay of hydrogen in volatile compounds in the coal.
Claim 11
Dependent Claim
86 words
The method of claim 1 wherein the step of measuring the free electrons comprises the step of (a) placing a magnetic field on the coal wherein the field has a fixed intensity; (b) forming an RF field at right angles to the magnetic field at a frequency related to the magnetic field intensity and the RF field has a specified duration; and (c) detecting with an RF coil an electron magnetic resonance response from the free electrons wherein the response integrates proportionate to free electron population.
Claim 12
Dependent Claim
19 words
The method of claim 10 further including the step of obtaining the log of the free electron response integral.
Claim 13
Dependent Claim
24 words
The method of claim 1 including the further step of multiplying the log by a constant to define the carbon content of the coal.
Claim 14
Dependent Claim
40 words
The method of claim 1 including the step of multiplying the heat content so obtained by the flow velocity of the coal to define the time rate at which the heating value is being delivered in a coal flow system.
Claim 15
Dependent Claim
34 words
The method of claim 1 including the step of multiplying the heat content per unit weight by the density of the coal to define the flow rate of coal in a coal flow system.
Claim 16
Dependent Claim
76 words
The method of claim 1 including the step of positioning a non-magnetic flow containing conduit for confining a flow stream of coal; placing a first magnet adjacent to the conduit to form a specified magnetic field across the conduit; and forming a right angle RF field in the conduit, the RF field and the magnetic field interacting in a resonant relationship to create an emitted RF signal indicative of the elemental population in the interacted fields.
Claim 17
Dependent Claim
16 words
The method of claim 15 including the step of measuring the amplitude of the RF signal.
Claim 18
Dependent Claim
102 words
The method of claim 15 including the step of positioning a second magnet adjacent to the conduit to form a second magnetic field across the conduit, and forming a second RF field in the conduit at right angles to the second magnetic field; causing the second RF field to interact with the second magnetic field in a resonant relationship to create an emitted RF signal indicative of the elemental population; and wherein said first RF signal is indicative of the free electron population of the coal and the second RF signal is indicative of hydrogen population of volatile compounds of the coal.
Claim 19
Dependent Claim
128 words
Apparatus for measuring heat content of coal, comprising: (a) magnet means for forming a magnetic field of specified intensity acting on a coal sample; (b) first RF field forming means forming a right angle RF field to the magnetic field; (c) second RF field forming means forming a right angle RF field to the magnetic field; (d) detector means responsive to RF output signals emitted from the coal, therebeing emitted first and second RF signals from the coal; (e) output means responsive to said detected first and second RF signals to form a calorific output for the coal; and (f) wherein the first and second said RF fields elicit a NMR signal from hydrogen in the coal and an EMR signal from unpaired electrons in the coal, respectively.
Claim 20
Dependent Claim
128 words
Apparatus for measuring heat content of coal, comprising: (a) magnet means for forming a magnetic field of specified intensity acting on a coal sample; (b) first RF field forming means forming a right angle RF field to the magnetic field; (c) second RF field forming means forming a right angle RF field to the magnetic field; (d) detector means responsive to RF output signals emitted from the coal, therebeing emitted first and second RF signals from the coal; (e) output means responsive to said detected first and second RF signals to form a calorific output for the coal; and (f) wherein the first and second said RF fields elicit a NMR signal from hydrogen in the coal and an EMR signal from unpaired electrons in the coal, respectively.
Claim 21
Dependent Claim
26 words
The method of claim 13 including time rate integrating heat content to indicate the total heat content of the coal flowing over a period of time.
Claim 22
Independent Claim
78 words
The method of measuring the density of the primary combustible part of coal in a conduit comprising the steps of: (a) measuring the NMR response of hydrogen in the coal; (b) measuring the EMR of free electrons in the coal; and (c) determining the concentration of the coal as a function of the hydrogen NMR and EMR free electron population value wherein the step of determining includes comparing with a standard value derived from a known coal assay.
Claim 23
Independent Claim
78 words
The method of measuring the density of the primary combustible part of coal in a conduit comprising the steps of: (a) measuring the NMR response of hydrogen in the coal; (b) measuring the EMR of free electrons in the coal; and (c) determining the concentration of the coal as a function of the hydrogen NMR and EMR free electron population value wherein the step of determining includes comparing with a standard value derived from a known coal assay.
Claim 24
Dependent Claim
36 words
The method of claim 20 including the step of multiplying the coal density so obtained by the flow velocity of the coal to define the rate of flow of the primary combustible part of the coal.
Claim 25
Dependent Claim
47 words
The method of claim 20 including the step of adding a measure of the density of coal constituents not measured by hydrogen NMR or EMR such as ash and sulfur to provide an indication of the total density of coal within the sensed region of the conduit.
Claim 26
Dependent Claim
17 words
The method of claim 21 wherein the flow velocity is obtained by the NMR or EMR measurement.
Claim 27
Dependent Claim
34 words
The method of claim 21 wherein the rate of flow so obtained is time integrated to measure the total mass flow over a period of time of the primary combustible part of the coal.
Claim 28
Dependent Claim
44 words
The method of claim 20 wherein the hydrogen NMR signal is separated into components based on T1 and T2 decay times to separately measure the proportional amounts of hydrogen in the volatile part of the coal and that in the water in the coal.
Claim 29
Dependent Claim
34 words
The method of claim 25 wherein the amount of hydrogen so measured in the volatiles in the coal is multiplied by a factor to provide a measure of the volatile content of the coal.
Claim 30
Dependent Claim
31 words
The method of claim 25 wherein the amount of hydrogen so measured in the water in the coal is used to provide a measure of the moisture content of the coal.
Claim 31
Dependent Claim
34 words
The method of claim 20 wherein the EMR signal so measured from the free electron in the coal is multiplied by a factor to provide a measure of the carbon content of the coal.
Claim 32
Dependent Claim
135 words
Apparatus for measuring the density of coal in a conduit comprising: (a) magnet means forming a magnetic field of specified intensity acting on a coal sample; (b) first RF field forming means forming a right angle RF field to the magnetic field; (c) second RF field forming means forming a right angle RF field to the magnetic field; (d) detector means responsive to RF output signals emitted from the coal, therebeing emitted first and second RF signals frm the coal; (e) output means responsive to said detector first and second RF signals to form a density measure for the coal in the said RF fields; and (f) wherein the first and second said RF fields elicit a NMR signal from hydrogen in the coal and an EMR signal from free electrons in the coal, respectively.
Claim 33
Dependent Claim
135 words
Apparatus for measuring the density of coal in a conduit comprising: (a) magnet means forming a magnetic field of specified intensity acting on a coal sample; (b) first RF field forming means forming a right angle RF field to the magnetic field; (c) second RF field forming means forming a right angle RF field to the magnetic field; (d) detector means responsive to RF output signals emitted from the coal, therebeing emitted first and second RF signals frm the coal; (e) output means responsive to said detector first and second RF signals to form a density measure for the coal in the said RF fields; and (f) wherein the first and second said RF fields elicit a NMR signal from hydrogen in the coal and an EMR signal from free electrons in the coal, respectively.
Claim 34
Dependent Claim
33 words
The apparatus of claim 29 wherein the first and second said RF Fields elicit a NMR signal from hydrogen in the coal and an EMR signal from unpaired electrons in the coal, respectively.
Claim 35
Dependent Claim
33 words
The apparatus of claim 18 wherein the first and second said RF fields elicite a NMR signal from hydrogen in the coal and an EMR signal from unpaired electrons in the coal, respectively.
Claim 36
Dependent Claim
35 words
The apparatus of claim 29 including means for multiplying the coal density so obtained by the flow velocity of the coal to define the rate of flow of the primary combustible part of the coal.
Claim 37
Dependent Claim
46 words
The apparatus of claim 29 including means for adding a measure of the density of coal constituents not measured by hydrogen NMR or EMR such as ash and sulfur to provide an indication of the total density of coal within the sensed region of the conduit.
Claim 38
Dependent Claim
15 words
The apparatus of claim 32 including means for obtaining flow velocity from the resonance measurements.
Claim 39
Dependent Claim
34 words
The apparatus of claim 32 including time integrator means to provide as an output a measure of the total mass flow over a period of time of the primary combustible part of the coal.
Claim 40
Dependent Claim
46 words
The apparatus of claim 29, including means to separate the hydrogen NMR signal into components based on T 1 and T 2 decay times to separately measure the proportional amount of hydrogen in the volatile part of the coal and in the water in the coal.
Claim 41
Dependent Claim
24 words
The apparatus of claim 36 including means to relate the hydrogen signal so measured from the volatiles to the volatile content of the coal.
Claim 42
Dependent Claim
24 words
The apparatus of claim 36 including means to relate the hydrogen signal so measured from the water to the moisture content of the coal.
Claim 43
Dependent Claim
21 words
The apparatus of claim 30 including means to relate the EMR signal so measured to the carbon content of the coal.
Claim 44
Independent Claim
153 words
A method of measuring heat content of coal comprising the steps of: (a) measuring the nuclear magnetic resonance (NMR) response of hydrogen in the coal; (b) measuring the electro-magnetic resonance (EMR) response of unpaired electrons in the coal; (c) scaling the magnitude of the NMR response to provide a signal, H, proportional to the available heat content of the hydrogen in the coal determined from a known coal assay; (d) scaling the magnitude of the EMR response to provide a signal, C, proportional to the available heat content of the carbon in the coal as determined from a known coal assay; (e) obtaining a signal of constant magnitude, D, to account for the loss or gain of additional heat from the remainder of the coal as determined from the known coal assay; and (f) using the signals, H, C and D to provide a signal proportional to the heat content of the coal.
Claim 45
Independent Claim
153 words
A method of measuring heat content of coal comprising the steps of: (a) measuring the nuclear magnetic resonance (NMR) response of hydrogen in the coal; (b) measuring the electro-magnetic resonance (EMR) response of unpaired electrons in the coal; (c) scaling the magnitude of the NMR response to provide a signal, H, proportional to the available heat content of the hydrogen in the coal determined from a known coal assay; (d) scaling the magnitude of the EMR response to provide a signal, C, proportional to the available heat content of the carbon in the coal as determined from a known coal assay; (e) obtaining a signal of constant magnitude, D, to account for the loss or gain of additional heat from the remainder of the coal as determined from the known coal assay; and (f) using the signals, H, C and D to provide a signal proportional to the heat content of the coal.
Claim 46
Dependent Claim
24 words
The method of claim 40 including the step of repetitively obtaining measurements from continuously flowing coal passing through a magnetic field of specified intensity.
Claim 47
Dependent Claim
19 words
The method of claim 40 including the step of impressing first and second separate magnetic fields on the coal.
Claim 48
Dependent Claim
56 words
The method of claim 40 including the step of forming a magnetic field of specified intensity on the coal, and then interrogating the coal with a RF field; detecting a RF signal from the coal in the magnetic field and the RF field; and obtaining an output from the detected RF signal encoding a measurement therein.
Claim 49
Dependent Claim
27 words
The method of claim 40 wherein unpaired electrons from the coal form the RF signal detected and the signal encodes unpaired electron population in an output signal.
Claim 50
Dependent Claim
86 words
The method of claim 40 wherein the step of measuring the free electrons comprises the step of: (a) placing a magnetic field on the coal wherein the field has a fixed intensity; (b) forming an RF field at right angles to the magnetic field at a frequency related to the magnetic field intensity and the RF field has a specified duration; and (c) detecting with an RF coil an electron magnetic resonance response from the free electrons wherein the response integrates proportionate to free electron population.
References Cited (Backward Citations)
US3473108A
Cited
US4390957A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |