[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

WO1995011429A1 - Apparatus and method for monitoring mass flow of solids - Google Patents

Apparatus and method for monitoring mass flow of solids Download PDF

Info

Publication number
WO1995011429A1
WO1995011429A1 PCT/US1993/009955 US9309955W WO9511429A1 WO 1995011429 A1 WO1995011429 A1 WO 1995011429A1 US 9309955 W US9309955 W US 9309955W WO 9511429 A1 WO9511429 A1 WO 9511429A1
Authority
WO
WIPO (PCT)
Prior art keywords
housing
particulate material
solid particulate
flux
flow rate
Prior art date
Application number
PCT/US1993/009955
Other languages
French (fr)
Inventor
William Jefferson Mccown
Original Assignee
E.I. Du Pont De Nemours And Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US07/801,920 priority Critical patent/US5253535A/en
Priority claimed from US07/801,920 external-priority patent/US5253535A/en
Application filed by E.I. Du Pont De Nemours And Company filed Critical E.I. Du Pont De Nemours And Company
Priority to PCT/US1993/009955 priority patent/WO1995011429A1/en
Priority to AU54442/94A priority patent/AU5444294A/en
Publication of WO1995011429A1 publication Critical patent/WO1995011429A1/en

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/76Devices for measuring mass flow of a fluid or a fluent solid material
    • G01F1/86Indirect mass flowmeters, e.g. measuring volume flow and density, temperature or pressure
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B65CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65GTRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
    • B65G53/00Conveying materials in bulk through troughs, pipes or tubes by floating the materials or by flow of gas, liquid or foam
    • B65G53/34Details
    • B65G53/40Feeding or discharging devices
    • B65G53/46Gates or sluices, e.g. rotary wheels
    • B65G53/4608Turnable elements, e.g. rotary wheels with pockets or passages for material
    • B65G53/4625Turnable elements, e.g. rotary wheels with pockets or passages for material with axis of turning perpendicular to flow
    • B65G53/4633Turnable elements, e.g. rotary wheels with pockets or passages for material with axis of turning perpendicular to flow the element having pockets, rotated from charging position to discharging position, i.e. discrete flow
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F11/00Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it
    • G01F11/10Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers moved during operation
    • G01F11/12Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers moved during operation of the valve type, i.e. the separating being effected by fluid-tight or powder-tight movements
    • G01F11/20Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers moved during operation of the valve type, i.e. the separating being effected by fluid-tight or powder-tight movements wherein the measuring chamber rotates or oscillates
    • G01F11/24Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers moved during operation of the valve type, i.e. the separating being effected by fluid-tight or powder-tight movements wherein the measuring chamber rotates or oscillates for fluent solid material

Definitions

  • the invention relates to an apparatus and method for monitoring the mass flow rate of particulate solids, particularly, titanium dioxide.
  • U.S. Patent 4,520,677 discloses a method and apparatus for indicating mass flow of a solid particulate material through a star wheel rotary feeder.
  • Such feeders include a plurality of vanes extending radially from a rotating shaft, mounted within a housing, to form a plurality of rotating pockets which receive, transport through the housing, and subsequently discharge solid particulate material.
  • the apparatus utilizes a source for discharg ⁇ ing a radiation flux positioned within the rotating shaft. The radiation flux is discharged toward a detector, through the shaft and pockets containing the solid particulate material.
  • This invention provides an apparatus and method for calculating mass flow rate of solid particulate material through a rotary feeder.
  • the apparatus comprises a rotary feeder having a rotatable shaft mounted within a housing.
  • the rotatable shaft has a plurality of vanes extending helically therefrom forming helical pockets which receive, transport and subsequently discharge solid particulate material.
  • the housing contains a housing inlet for receiving the solid particulate material into the helical pockets and a housing outlet through which the solid particulate material is discharged from the helical pockets.
  • the rotatable shaft is operationally connected to a means for rotating the rotatable shaft.
  • the apparatus further comprises a flux discharging radiation source disposed within the rotatable shaft, a first and second flux- radiation detectors disposed externally of uhe housing, means for measuring the flux radiation received by the detectors and converting the measurements to electrical signals for trans ⁇ mitting, means for measuring rate of rotation of the rotatable shaft and converting the measurement to an electrical signal for transmitting; a means for calculating mass flow rate of particulate solid material based on the signals received from the means for measuring the flux radiation received by the detectors and the means for measuring rate of rotation; and a means for displaying the calculated mass flow rate.
  • the first detector is disposed downstream of the housing inlet and upstream of the housing outlet, i.e., where the pocket is filled with solid particulate material.
  • the second detector is disposed downstream of the housing outlet and upstream of the housing inlet, i.e., where the pocket has discharged the solid particulate material.
  • a known amount of flux radiation is discharged from the source toward the first and second detectors.
  • the flux radiation therefore passes through each pocket twice during rotation, once in the filled position and again in the discharged position.
  • the amount of flux radiation received at the first and second detectors is measured.
  • the shaft and helical pockets is measured.
  • the measurements are converted to electrical signals and are transmitted to the means for calculating the mass flow rate.
  • the means for calculating the mass flow rate can accurately determine the actual mass discharged.
  • the method uses the accurate mass determination and the measurement of rotation of the shaft to calculate an accurate mass flow rate which is then displayed.
  • FIG.l is a side elevation, in section, of an apparatus of the invention.
  • FIG.2 is a top view of the device of FIG. 1.
  • the feeder 10 includes a housing 12 within which is mounted a rotatable shaft 14. Helically extending from the shaft are a plurality of vanes 16 which form within the housing a plurality of helical pockets 18. The helical pockets 18 are bounded laterally by side walls 19 of the vanes.
  • the housing is generally affixed to an inlet conduit 20 and an outlet conduit 22 through which flow a solid particulate material 24 such as titanium dioxide. The particulate material 24 does not consistently display free flowing characteristics.
  • the housing 12 has a housing inlet 26 for receiving solid particulate material 24 into the helical pockets 18 and a housing outlet 28 through which the solid particulate material 24 is discharged from the helical pockets 18.
  • the shaft 14 is rotated by a rotating means, not shown, thereby rotating the vanes 16 and helical pockets 18 to transport solid particulate material 24 from the housing inlet 24 to the housing outlet 28.
  • the rotating means is a motor coupled with a gear mechanism to enable the rate of rotation to be controlled by the operator.
  • the apparatus has a means, not shown, for measuring the rate of rotation of the shaft 14 and helical pockets 18.
  • the means is a tachometer.
  • the flux radiation is directed from the source 32 through the shaft 14, pockets 18 and vanes 16 and housing 12 to flux radiation detectors 34A and 34B.
  • the flux radiation source is Cesium-137 which provides excellent penetration through the shaft 14, vanes 16 and housing 12 and through the solid particulate material 24.
  • the amount of flux radiation and number of flux radiation sources required is established by analyzing parameters such as composition and thickness of the shaft 14, vanes 16, and housing 12 , the density of the solid particulate material 24 and the span. Multiple flux radiation sources of differing strengths may be required to achieve a uniform flux radiation field intensity at the face of the detector. The determination of individual source strength, plurality and spacing between sources is application dependent and is largely governed by the physical dimensions of the feeder pocket width and separation between radioactive source and detector.
  • the radiation source material is placed in a suitable holder surrounded with lead in all directions except where the radiation is colli ated and beamed to detectors 34A and 34B.
  • the lead effectively blocks radiation to a safe field intensity level which complies with applicable national and international standards.
  • the flux radiation is attenuated during passage to a degree which is a function of the mass of the shaft 14, vane 16 and housing 12, and the solid particulate material 24 contained within the helical pocket 18.
  • the detectors which are highly sensitive and stable, preferably consist of an ionization chamber and, more preferably, include a pre-amplifier.
  • the detectors are mounted directly opposite a directed beam from the radiation source. The detectors extend the length of the pockets as does the collimated flux radiation.
  • the detectors 34A and 34B As the flux passes from the source 32 to the detectors 34A and 34B, indicated by the dotted lines LI and L2, it is attenuated by any material in its path.
  • the detectors receive the attenuated collimated beam of flux radiation and generate an electrical signal, preferably a low impedance voltage signal, inversely proportional to the mass of the material through which the beam passed.
  • the electrical signal from the detectors 34A and 34B and the means for measuring the rate of rotation of the shaft is provided to a means for calculating mass flow rate, not shown, which analyzes the signals.
  • the calculating means is preferably a remote electronic monitor having a calculating and displaying means.
  • the detectors, means for measuring rotation and monitor are integrated to yield the quality of solid particulate material retained within a given pocket after discharge of the solid particulate material.
  • the monitor compares the value of the signal received from the first detector at the filled position with the value of the signal received from the second derector at the discharged position to determine the mass of solid particulate material actually discharged from a given pocket.
  • the difference between the determined mass contained in a given pocket in its full and discharged positions provides an accurate measure of the mass of solid particulate material discharged from the feeder. This determination takes into account the amount of material left in the pocket subsequent to discharge of most of the contained solids particulate material.
  • the mass determined is multiplied by the flow rate as measured by the means for measuring the rotation rate to provide the mass flow rate of the solid particulate material.
  • the mass flow rate is preferably displayed on a digital readout.
  • the inventors have found this apparatus and method to be of particularly advantage for use in measuring the transport of titanium dioxide which has a tendency to adhere to the pockets.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Measuring Volume Flow (AREA)

Abstract

A method and apparatus for transporting solid particulate material and calculating mass flow rate of the material through a rotary feeder having helical pockets is provided. At least one radiation source and two or more detectors are positioned in a manner whereby radiation flux is directed through, and attenuated by particular material contained in a helical pocket. The amount of attenuation is measured at least when the pocket is filled with material and when the pocket has discharged most of the material. The difference in the amount of flux detected at the filled and discharged positions is used to determine the mass flow rate of the particulate material.

Description

APPARATUS AND METHOD FOR MONITORING MASS FLOW OF SOLIDS
BACKGROUND OF THE INVENTION
Field of the Invention The invention relates to an apparatus and method for monitoring the mass flow rate of particulate solids, particularly, titanium dioxide.
Description of the Prior Art In many chemical processes which include transporting particulate solids, it is important to continuously or intermitt¬ ently monitor the solids' mass flow rate in order to properly maintain the process controls needed to obtain satisfactory product. For example, during finish processing of titanium dioxide pigment, an accurate measurement of the mass flow rate of the titanium dioxide improves significantly the quality of the finished product.
Techniques presently used to determine mass flow include utilization of a rotary feeder system having a predetermined rate of rotation and inferring the mass flow rate from the rate of rotation. There are several problems with this technique, all of which result in inaccurate mass flow rate determinations. Although the volume of the feeder pockets is known, the pockets are not uniformly filled. Also, particle size, moisture content and other variables affect the mass transfer rate for a given revolution rate. Additionally, fine materials tend to be retained for a period of time within the feeder pockets and the surrounding casing as a result of pressure differentials.
U.S. Patent 4,520,677 discloses a method and apparatus for indicating mass flow of a solid particulate material through a star wheel rotary feeder. Such feeders include a plurality of vanes extending radially from a rotating shaft, mounted within a housing, to form a plurality of rotating pockets which receive, transport through the housing, and subsequently discharge solid particulate material. The apparatus utilizes a source for discharg¬ ing a radiation flux positioned within the rotating shaft. The radiation flux is discharged toward a detector, through the shaft and pockets containing the solid particulate material. By measuring the attenuation of the radiation flux at various points, e.g., when directed through a parallel vane, a filled pocket or a discharged pocket, a measurement of the mans can be calculated. However, this method loses accuracy because an estimated adjustment is needed to accommodate peaks in the laiiation fiux attenuation caused by the vanes being parallel in a star wheel rotary feeder.
It is therefore desirable to provide an apparatus and method for determining particulate solid mass flow rate which alleviate the discussed limitations. It is further desirable to provide an apparatus and system which is simple, reliable and which takes advantage of existing technology and components.
SUMMARY OF THE INVENTION
This invention provides an apparatus and method for calculating mass flow rate of solid particulate material through a rotary feeder.
The apparatus comprises a rotary feeder having a rotatable shaft mounted within a housing. The rotatable shaft has a plurality of vanes extending helically therefrom forming helical pockets which receive, transport and subsequently discharge solid particulate material. The housing contains a housing inlet for receiving the solid particulate material into the helical pockets and a housing outlet through which the solid particulate material is discharged from the helical pockets. The rotatable shaft is operationally connected to a means for rotating the rotatable shaft.
The apparatus further comprises a flux discharging radiation source disposed within the rotatable shaft, a first and second flux- radiation detectors disposed externally of uhe housing, means for measuring the flux radiation received by the detectors and converting the measurements to electrical signals for trans¬ mitting, means for measuring rate of rotation of the rotatable shaft and converting the measurement to an electrical signal for transmitting; a means for calculating mass flow rate of particulate solid material based on the signals received from the means for measuring the flux radiation received by the detectors and the means for measuring rate of rotation; and a means for displaying the calculated mass flow rate.
The first detector is disposed downstream of the housing inlet and upstream of the housing outlet, i.e., where the pocket is filled with solid particulate material. The second detector is disposed downstream of the housing outlet and upstream of the housing inlet, i.e., where the pocket has discharged the solid particulate material.
In the method, a known amount of flux radiation is discharged from the source toward the first and second detectors.
The flux radiation therefore passes through each pocket twice during rotation, once in the filled position and again in the discharged position. The amount of flux radiation received at the first and second detectors is measured. The rate of rotation of
- the shaft and helical pockets is measured. The measurements are converted to electrical signals and are transmitted to the means for calculating the mass flow rate.
The use of a rotary feeder with helical pockets allows a constant amount of the housing and rotating shaft with its helical vanes to be-in the detectors' view path.
Since the attenuation of the flux radiation due to the housing, shaft and vanes is constant, the difference between the signal of the radiation received by the first detector and the signal of the radiation received by the second detector is due to the mass of discharged solid particulate material. Therefore the means for calculating the mass flow rate can accurately determine the actual mass discharged. The method uses the accurate mass determination and the measurement of rotation of the shaft to calculate an accurate mass flow rate which is then displayed.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages, nature and additional features of the invention will become more apparent from the following description, taken in connection with the accompanying drawings, in which:
FIG.l is a side elevation, in section, of an apparatus of the invention;
FIG.2 is a top view of the device of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1 through 2, there is shown an exemplary rotary feeder 10 in accordance with the invention. The feeder 10 includes a housing 12 within which is mounted a rotatable shaft 14. Helically extending from the shaft are a plurality of vanes 16 which form within the housing a plurality of helical pockets 18. The helical pockets 18 are bounded laterally by side walls 19 of the vanes. The housing is generally affixed to an inlet conduit 20 and an outlet conduit 22 through which flow a solid particulate material 24 such as titanium dioxide. The particulate material 24 does not consistently display free flowing characteristics. The housing 12 has a housing inlet 26 for receiving solid particulate material 24 into the helical pockets 18 and a housing outlet 28 through which the solid particulate material 24 is discharged from the helical pockets 18.
The shaft 14 is rotated by a rotating means, not shown, thereby rotating the vanes 16 and helical pockets 18 to transport solid particulate material 24 from the housing inlet 24 to the housing outlet 28. Preferably, the rotating means is a motor coupled with a gear mechanism to enable the rate of rotation to be controlled by the operator. The apparatus has a means, not shown, for measuring the rate of rotation of the shaft 14 and helical pockets 18. Prefer¬ ably, the means is a tachometer.
With a clockwise rotational motion as shown in FIG.l, solid particulate material 24 enters and substantially fills the helical pocket 18 at the position identified as PI, is carried through the housing and is discharged at position P3. At position P2, the helical pocket 18 is substantially filled, and its volume is readily defined between the shaft 14, the interior surface 30 of the housing 12, and the side wall 19 of the vane 16. A certain amount of the solid particulate material 24 often adheres within the helical pocket 18. Subsequent to the discharge of the bulk of the material within the pocket, the substantially empty pocket continues its rotation through position P4 and returns to position PI to be refilled. Means for discharging flux radiation, such as one or more gamma source(s) 32, are mounted within the rotatable shaft 14. The flux radiation is directed from the source 32 through the shaft 14, pockets 18 and vanes 16 and housing 12 to flux radiation detectors 34A and 34B. Preferably, the flux radiation source is Cesium-137 which provides excellent penetration through the shaft 14, vanes 16 and housing 12 and through the solid particulate material 24. The amount of flux radiation and number of flux radiation sources required is established by analyzing parameters such as composition and thickness of the shaft 14, vanes 16, and housing 12 , the density of the solid particulate material 24 and the span. Multiple flux radiation sources of differing strengths may be required to achieve a uniform flux radiation field intensity at the face of the detector. The determination of individual source strength, plurality and spacing between sources is application dependent and is largely governed by the physical dimensions of the feeder pocket width and separation between radioactive source and detector. For example, in a process utilizing a 14 inches, (35.56 cm), wide rotary feeder and Ti02 particulate material, three radiation sources of 10, 5 and 10 milliCuries each (total of 25 milliCuries) are used to create a uniform field. The amount of flux radiation is held to a minimum to achieve optimum sensitivity, economy and safety. Radioisotopes other than Cesium-137 can also be used as the flux radiation source.
Preferably, the radiation source material is placed in a suitable holder surrounded with lead in all directions except where the radiation is colli ated and beamed to detectors 34A and 34B. The lead effectively blocks radiation to a safe field intensity level which complies with applicable national and international standards. The gamma rays, emitted from the radioisotope source 32, penetrates all materials. The energy of the gamma rays is reduced in proportion to the mass of the material through which it passes. The passage of gamma rays through a substance does not affect the substance's properties nor does the substance become radioactive. The flux radiation is attenuated during passage to a degree which is a function of the mass of the shaft 14, vane 16 and housing 12, and the solid particulate material 24 contained within the helical pocket 18.
Positioned beyond the volume of the helical pocket 18 and external to the housing 12 are at least a first and second means for detecting and preferably, signalling xadiation flu::, such άs gamma detectors 34A and 34B. The detectors, which are highly sensitive and stable, preferably consist of an ionization chamber and, more preferably, include a pre-amplifier. The detectors are mounted directly opposite a directed beam from the radiation source. The detectors extend the length of the pockets as does the collimated flux radiation.
As the flux passes from the source 32 to the detectors 34A and 34B, indicated by the dotted lines LI and L2, it is attenuated by any material in its path. The detectors receive the attenuated collimated beam of flux radiation and generate an electrical signal, preferably a low impedance voltage signal, inversely proportional to the mass of the material through which the beam passed. The electrical signal from the detectors 34A and 34B and the means for measuring the rate of rotation of the shaft, is provided to a means for calculating mass flow rate, not shown, which analyzes the signals. The calculating means is preferably a remote electronic monitor having a calculating and displaying means.
The detectors, means for measuring rotation and monitor are integrated to yield the quality of solid particulate material retained within a given pocket after discharge of the solid particulate material. The monitor compares the value of the signal received from the first detector at the filled position with the value of the signal received from the second derector at the discharged position to determine the mass of solid particulate material actually discharged from a given pocket. The difference between the determined mass contained in a given pocket in its full and discharged positions provides an accurate measure of the mass of solid particulate material discharged from the feeder. This determination takes into account the amount of material left in the pocket subsequent to discharge of most of the contained solids particulate material. The mass determined is multiplied by the flow rate as measured by the means for measuring the rotation rate to provide the mass flow rate of the solid particulate material. The mass flow rate is preferably displayed on a digital readout.
Systems containing a flux radiation source, detectors and monitor are known to these skilled in the art and are commercially available. One example is the X91 Series Density Monitor sold by the Ronan Engineering Company, Measurements Division of Florence, Kentucky.
The inventors have found this apparatus and method to be of particularly advantage for use in measuring the transport of titanium dioxide which has a tendency to adhere to the pockets.
Since numerous changes may be made in the above-described apparatus and system without departing from the spirit and the scope of the disclosure, it is intended that the description be received as illustrative, and not in a limiting sense.

Claims

What is claimed is:
1. An apparatus for transporting solid particulate material and calculating mass flow rate of the material, the apparatus comprising:
(a) a rotary feeder comprising i/ a rotatable shaft having a plurality of vanes extending helically therefrom so as to form helical pockets; ii/ a housing; iii/ a housing inlet for receiving solid particulate material into the helical pockets; iv/ a housing outlet for discharging solid particulate material from the helical pockets; and v/ means for rotating the rotatable shaft;
(b) at least one flux discharging radiation source disposed within the rotatable shaft; (c) a first flux radiation detector disposed externally of the housing downstream of the housing inlet and upstream of the housing outlet;
(d) a second flux radiation detector disposed externally of the housing downstream of the housing outlet and upstream of the housing inlet;
(e) means for measuring and signaling the rate of rotation of the rotatable shaft;
(f) means for measuring and signaling the amount of flux radiation transmitted through the helical pockets to the first and second detectors;
(g) means for calculating mass flow rate of the solid particulate material from a specific helical pocket by correlating the signals of rate of rotation, and signals of flux radiation received by the first and second detectors; and (h) means for displaying mass flow rate.
2. The apparatus of claim 1 wherein the at least one flux discharging radiation source is a gamma radiation source.
3. The apparatus of claim 1 wherein the means of measuring the rate of rotation of the feeder is a gear-driven tachometer.
4. The apparatus of claim 1 comprising: (a) a rotary feeder comprising; i/ a rotatable shaft having a plurali-y of vanes extending helically therefrom so as to form helical pockets; ii/ a housing; iii/ a housing inlet for receiving solid particulate material into the helical pockets; iv/ a housing outlet for discharging solid particulate material from the helical pockets; and v/ a motor coupled with a gear mechanism for rotating the rotatable shaft;
(b) at least one gamma radiation discharging source disposed within the rotatable shaft;
(c) a first gamma radiation detecting, measuring and electrically signaling device disposed externally of the housing downstream of the housing inlet and upstream of the housing outlet;
(d) a second gamma radiation detecting, measuring and electrically signaling device disposed externally of the housing downstream of the housing outlet and upstream of the housing inlet;
(e) a tachometer for measuring and electrically signaling the rate of rotation of the rotatable shaft; and
(g) a monitor for calculating and displaying mass flow rate of the solid particulate material based on the signal from the tachometer and comparing the signals from the first and second detecting measuring and signaling devices.
5. A method for determining mass flow rate of a solid particulate material which comprises: a) transporting a solid particulate material through an apparatus comprising: i/ a rotating shaft having a plurality of vanes extending helically therefrom to form helical pockets; ii/ a housing; iii/ a housing inlet for receiving solid particulate material into the helical pockets; iv/ a housing outlet for discharging solid particulate material from the helical pockets; v/ a means for rotating the rotating shaft; vi/ at least one flux discharging radiation source disposed within the rotating shaft; vii/ a first flux radiation detector disposed externally of the housing downstream of the housing inlet and upstream of the housing outlet; viii/ a second flux radiation detector disposed externally of the housing downstream of the housing outlet and upstream of the housing inlet; ix/ a means for measuring rate of rotation of the rotating shaft and for converting the measurement to an electrical signal; x/ means for measuring the flux radiation transmitted through the helical pockets to the first and second detector and for converting the measurements to electrical signals; xi/ means for transmitting the electrical signals; xii/ means for receiving the electrical signals and calculating mass flow rate of the solid particulate material; and xiii/ a means for displaying mass flow rate; (b) discharging a known amount of flux radiation from the at least one^ flux radiation source toward the first and second flux radiation detectors;
(c) measuring flux radiation received at the first and second flux radiation detectors for a given helical pocket;
(d) converting the measurements received by the first and second detectors to electrical signals;
(e) measuring rate of rotation of the rotating shaft and converting the measurement to an electrical signal;
(f) transmitting the signals to the means for calculating the mass flow rate;
(g) calculating mass flow rate by i/ determinging mass of solid particulate material discharged from a given helical pocket by comparing the signal of the flux radiation received from the first detector to the signal of flux radiation received from the second detector; ii/ determining flow rate by using the signal from the means for measuring the rate of rotation; and iii/ multiplying the mass of solid particulate material discharged from the given helical pocket by the flow rate to provide a calculated mass flow rate; and
(h) displaying the calculated mass flow rate.
6. A method according to claim 5, in which the at least one radiation source is Cesium-137.
7. A method according to claim 5 in which the solid particulate material is titanium dioxide.
PCT/US1993/009955 1991-12-03 1993-10-19 Apparatus and method for monitoring mass flow of solids WO1995011429A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US07/801,920 US5253535A (en) 1991-12-03 1991-12-03 Apparatus and method for monitoring mass flow of solids
PCT/US1993/009955 WO1995011429A1 (en) 1991-12-03 1993-10-19 Apparatus and method for monitoring mass flow of solids
AU54442/94A AU5444294A (en) 1991-12-03 1993-10-19 Apparatus and method for monitoring mass flow of solids

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US07/801,920 US5253535A (en) 1991-12-03 1991-12-03 Apparatus and method for monitoring mass flow of solids
PCT/US1993/009955 WO1995011429A1 (en) 1991-12-03 1993-10-19 Apparatus and method for monitoring mass flow of solids

Publications (1)

Publication Number Publication Date
WO1995011429A1 true WO1995011429A1 (en) 1995-04-27

Family

ID=26787072

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1993/009955 WO1995011429A1 (en) 1991-12-03 1993-10-19 Apparatus and method for monitoring mass flow of solids

Country Status (2)

Country Link
AU (1) AU5444294A (en)
WO (1) WO1995011429A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT501790A1 (en) * 2005-04-20 2006-11-15 Helmut Simon Ing Orgler CELL WHEEL SLUT, FOR BIG BULK WITH LOW DRIVE PERFORMANCE

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2273909A1 (en) * 1974-06-04 1976-01-02 Linden Alimak Ab POWER SUPPLY FOR A SOIL STABILIZER
EP0042245A1 (en) * 1980-06-14 1981-12-23 Claydon Yield-O-Meter Limited Crop metering device for combine harvesters
EP0079421A1 (en) * 1981-10-30 1983-05-25 KRW Energy Systems Inc. Improved solids mass flow indication
DE3417583A1 (en) * 1984-05-11 1985-11-21 Endress U. Hauser Gmbh U. Co, 7867 Maulburg Arrangement for measuring mass flow rate

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2273909A1 (en) * 1974-06-04 1976-01-02 Linden Alimak Ab POWER SUPPLY FOR A SOIL STABILIZER
EP0042245A1 (en) * 1980-06-14 1981-12-23 Claydon Yield-O-Meter Limited Crop metering device for combine harvesters
EP0079421A1 (en) * 1981-10-30 1983-05-25 KRW Energy Systems Inc. Improved solids mass flow indication
US4520677A (en) * 1981-10-30 1985-06-04 The United States Of America As Represented By The United States Department Of Energy Solids mass flow indication with radiation
DE3417583A1 (en) * 1984-05-11 1985-11-21 Endress U. Hauser Gmbh U. Co, 7867 Maulburg Arrangement for measuring mass flow rate

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT501790A1 (en) * 2005-04-20 2006-11-15 Helmut Simon Ing Orgler CELL WHEEL SLUT, FOR BIG BULK WITH LOW DRIVE PERFORMANCE
AT501790B1 (en) * 2005-04-20 2008-01-15 Helmut Simon Ing Orgler CELL WHEEL SLICE FOR PROMOTING BULK GOODS

Also Published As

Publication number Publication date
AU5444294A (en) 1995-05-08

Similar Documents

Publication Publication Date Title
US11280748B2 (en) Conveyor system and measuring device for determining water content of a construction material
FI88212B (en) SJAELVREGLERANDE, ON-LINE, REALTIDSANALYSATOR FOER BULKMATERIAL
US4506541A (en) Measurement of bulk density of particulate materials
US5654551A (en) Method and apparatus for the measurement of the mass flow rates of fluid components in a multiphase slug flow
US4266425A (en) Method for continuously determining the composition and mass flow of butter and similar substances from a manufacturing process
GB1235856A (en) Improvements in or relating to the measurement of the flow of a particulate material
US3796873A (en) Container fill weight control using nuclear radiation
US5253535A (en) Apparatus and method for monitoring mass flow of solids
US3761712A (en) Gauge for determining the percentage by weight of moisture contained in a bulk material transported on a moving conveyor
US4870278A (en) Wide-range fluid level detector
US3955087A (en) Apparatus for measuring moisture in moving bulk material using a lithium-7 radiation source
US4794256A (en) Fast neutron process measurement system
US3600574A (en) Radiometric method and apparatus for measuring and controlling foundry sand moisture
WO1995011429A1 (en) Apparatus and method for monitoring mass flow of solids
US4520677A (en) Solids mass flow indication with radiation
US4743760A (en) Method and apparatus for metering flowable particulates
KR19990008375A (en) Method and apparatus for continuous detection of moisture in bulk materials
GB2211602A (en) Measuring bulk density and/or mass flow rate using positrons
CN101017126B (en) Method for online measuring density by double detector and online densimeter
US4205230A (en) Solid materials flow rate measurement
Beck et al. Current industrial methods of solids flow detection and measurement
JPH09189587A (en) Powder flowmeter
RU2242747C2 (en) Moisture content measuring apparatus
SU472613A1 (en) Device for radioisotope measuring of mass of flowing granular materials
US2996620A (en) Speed measuring system

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU CA

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: CA

122 Ep: pct application non-entry in european phase