APPARATUS AND METHOD FOR ESTIMATION OF ORE QUALITY USING COLOR
CORRELATIONS
FIELD OF THE INVENTION
The invention pertains to the estimation of ore quality using a light reflection technique.
More particularly, the invention pertains to the estimation of coal fine quality in the tailings
stream of a coal processing operation, the quality determined by light reflection at a specific
wavelength.
BACKGROUND
Ore processing operations inevitably produce fine particles that in the past led to great
process losses. Ore processing operations have developed ways to process these fine particles in
order to make the overall operation more efficient than before. To make the fine particle
processing as efficient as possible, it is important to know the quality of the fine particles
entering the fine particle processing stages of the overall operation. Knowing the quality of the
fine particles allows for process adjustments in the fine particle processing stages.
Cierpisz et al., "Coal Quality Monitoring and Control in Poland," discusses the
importance of measuring coal quality for such operations. The article initially discusses the
measurement of coal quality using a gamma-ray back-scattered method. It continues by
discussing the measurement of color in flotation tailings using a MPOF device. The article
concludes by discussing various laboratory techniques used to determine the quality of coal.
Oblad et al, "Control of Fine Coal Flotation Using an Optoelectronic Tailings Ash
Detector," discusses a new optoelectronic instrument that measures the amount of fine coal in the
solids fraction of a slurry of water, coal, and clay, either in the flotation cell or in the tailings.
The instrument uses a collimated illumination source and a photoconductor chosen to have the
correct voltage or frequency response to measure the internal reflectance of the slurry.
WO/2007/03341 5, by Lambert, describes a method of online analysis of mineral waste
content of a slurry in a mineral separation process, the method including the steps of: measuring
the density of the slurry, measuring the concentration of solids in the slurry, calculating the
density of solids in the slurry from the slurry density and the solids concentration, and calculating
the mineral waste content from the solids density. Lambert also provides an online analyzer for
mineral waste content of a slurry in a mineral separation process.
Accordingly, there is a need for estimating the quality of ore in the tailings stream of an
ore processing operation. Desirably, the ore quality is determined using a non-destructive, realtime
technique. More desirably, once determined, the ore quality can be instantly input into a
control loop that controls the coal processing operation, particularly the fine particle processing
stages, as efficiently as possible.
SUMMARY OF THE INVENTION
The comparative analysis monitor ("CAM") is a device that allows for quick and simple
field tests of ore content in slurry or fine cake. The CAM can be used to provide a measured
basis to optimize plant performance. A sample is presented to the CAM, which then produces an
output that represents the ash concentration of the sample, a typical measure of ore quality. The
sample can be measured continuously, intermittently, or individually. The CAM may be
constructed to be easily portable or relatively stationary.
The use of the CAM in process streams allows for dose optimization for frothers,
modifiers, promoters, and collectors in flotation circuits and other circuits where addition or
subtraction of reagents influences grade, quality, yield, or recovery that can be recognized by
color. Additionally, the CAM will allow for detection of fine ore quality in separator process
streams including, but not limited to, flotation, spirals, teeter bed separators, reflux classifiers,
and shaking tables. The information gathered by the invention can be input into feedback control
loops.
The CAM allows for optimization of ore processing operations based on the color of the
tailings stream of a separator. The CAM can be used to assess the quality of other materials as
well, including but not limited to a feed stream, a concentrate, or a filter cake within an ore
processing operation.
These and other features and advantages of the present invention will be apparent from
the following detailed description, in conjunction with the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The benefits and advantages of the present invention will become more readily apparent
to those of ordinary skill in the relevant art after reviewing the following detailed description and
accompanying drawings, wherein:
FIG. 1 is a block diagram of the CAM; and
FIG. 2 is a flow diagram of a typical process that includes the installation of a CAM.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
While the present invention is susceptible of embodiment in various forms, there is shown
in the drawings and will hereinafter be described a presently preferred embodiment with the
understanding that the present disclosure is to be considered an exemplification of the invention
and is not intended to limit the invention to the specific embodiment illustrated.
It should be further understood that the title of this section of this specification, namely,
"Detailed Description of the Preferred Embodiment," relates to a requirement of the United
States Patent Office, and does not imply, nor should be inferred to limit the subject matter
disclosed herein.
As shown in FIG. 1, a light beam generator 12 shines a light beam 14 into a sample 16.
The beam 14 has a wavelength in the visible spectrum. Light 18 reflects from the sample 16 and
is detected by the detector 20. The detector 20 converts the reflected light 18 into an electrical
signal 22, which can be output in several different fashions (not shown).
A typical use for the CAM shown in FIG. 2. A flotation separator 110 has a tailings
stream 112 that leave the flotation separator 110. The tailings stream 112 can contain fine
particles (not shown). The tailings stream 112 is analyzed by the CAM 114, which sends an
electrical signal 116 to a control system 118. The electrical signal 116 can vary corresponding to
the quality of coal fines that it measures. The tailings stream 112 passes through the CAM 114
and into the thickener. This is intended to illustrate a mere typical use for the CAM and should
in no way be construed to limit the invention to this single use.
The control system 118 can be configured to control heating, cooling, pumps, valves,
levels, temperature, pressure, or any other process function or parameter, which will be
recognized by one skilled in the art.
The CAM 114 can be built to allow for ease of portability, or it can be built to be more or
less stationary and devoted to one ore processing operation. The CAM 114 preferably measures
the tailings stream 112, but those skilled in the art will recognize that the CAM 114 may be used
to measure any of several process streams including, but not limited to, flotation, spirals, teeter
bed separators, reflux classifiers, and shaking tables. The CAM 114 may also measure the
quality of ore fines in filter cakes.
The CAM 114 preferably outputs an electrical signal having a variable magnitude
depending on the measured ore quality. However, those skilled in the art will recognize that the
electrical signal can take any of several forms, so long as the signal may vary depending on the
measured ore quality.
The CAM 114 may also send the electrical signal to an outputting device, more
particularly a visual display (not shown). The visual display can be any of several devices,
including, but not limited to, a monitor, a printer, a plotter, a projection screen, and like devices.
The outputting device can communicate the ore quality as measured by the CAM 114 as a
quantifiable value. The quantifiable value can be a Nalco Slurry Index value.
All patents referred to herein, are hereby incorporated herein by reference, whether or not
specifically done so within the text of this disclosure.
In the present disclosure, the words "a" or "an" are to be taken to include both the singular
and the plural. Conversely, any reference to plural items shall, where appropriate, include the
singular.
From the foregoing it will be observed that numerous modifications and variations can be
effectuated without departing from the true spirit and scope of the novel concepts of the present
invention. It is to be understood that no limitation with respect to the illustrated specific
embodiments or examples is intended or should be inferred. The disclosure is intended to cover
by the appended claims all such modifications as fall within the scope of the claims.
CLAIMS
We claim:
1. An apparatus for measuring a quality of ore fines in an ore processing operation, the apparatus
comprising:
a light generator, the light generator generating a focused beam, the focused beam having
a wavelength in the visible spectrum;
a detector, the detector detecting a reflected signal and converting the reflected signal into
an electrical signal; and
optionally an outputting device;
wherein the light generator shines the focused beam into a process stream of the ore processing
operation;
wherein the detector detects the reflected signal from the light generator shining the focused
beam into the process stream of the ore processing operation; and
wherein the outputting device converts the electrical signal into a quantifiable value
corresponding to the quality of ore fines of the process stream of the ore processing
operation
wherein the quality of ore fines corresponds to the ash concentration of the process stream.
2. The apparatus of claim 1, wherein the process stream is a stream to or from a separator.
3. The device of claim 2, wherein the electrical signal is operatively input into a control loop
controlling the ore processing operation.
4. The device of claim 2, wherein the electrical signal is a variable signal.
5. The device of claim 2, wherein the outputting device is a visual display.
6. The device of claim 2, wherein the quantifiable value is the Nalco Slurry Index.
7. A method for improving ore separation efficiency of an ore processing operation, the method
comprising the steps of:
analyzing a slurry ash concentration in a process stream of the ore processing operation;
outputting an electrical signal corresponding to the slurry ash concentration;
wherein the analyzing is performed by
shining a light beam into the process stream of the ore processing operation, the light
beam having a wavelength in the visible spectrum, and
detecting light reflected from the shining of the light beam into a process stream of the
ore processing operation.
8. The method of claim 7, wherein the process stream is a tailings stream.
9. The method of claim 7, wherein the method comprises the additional step of translating the
electrical signal into a Nalco Slurry Index value.
10. The method of claim 9, wherein the method comprises the additional step of comparing the
Nalco Slurry Index value to a set point.
11. The method of claim 10, wherein the comparing provides an input into a control loop
controlling the ore processing operation.
12. The method of claim 7, wherein the ore processing operation is a coal processing operation.