JPH0621866B2 - Method and apparatus for measuring color of powder in air flow - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for measuring color of powder in an air stream and an apparatus therefor.

(Prior Art) As a color measuring means, a light projecting unit that projects light on a sample and a light receiving unit that receives reflected light from the sample by this light projecting are provided, and from the characteristics of the reflected light obtained by the light receiving unit, A colorimeter for obtaining the color of a sample, that is, a value of hue, lightness or saturation, or a color difference meter for measuring a difference from a standard color is generally known. Such a colorimeter can be used for measuring the color of a fixed object such as a metal, a coating film, cloth, and paper.

(Problems to be Solved by the Invention) It is difficult to measure the color of powder in an air stream, for example, ash in exhaust gas from coal combustion, with a conventional colorimeter as it is. On the other hand, it is conceivable to collect and fix a fixed amount of powder from the air flow and apply the colorimeter to this, but this is not only troublesome in quantitatively collecting and fixing the powder, but also in advance. Even if the amount of powder collected is determined, if the properties of the powder change (in the case of the ash of the above exhaust gas, the properties of the ash change due to changes in the coal combustion conditions and the type of coking coal), the specified recovery The amount is insufficient for measuring the powder color, and measurement error may occur. Also, when adopting the method of collecting and fixing a large amount of powder in advance in anticipation of changes in powder properties,
It takes a long time to complete the color measurement, and the measurement result cannot be reflected in the control on the powder generation source side.

(Means for Solving Problems) As a means for solving the above problems, the present invention aims to provide a method for measuring the color of powder in an air stream and an apparatus used for carrying out this method.

That is, the above-mentioned color measuring method is to adsorb the powder in the air flow to the filter paper and measure the change with time of the reflected light generated by the projection on this filter paper, and after the reflected light becomes a steady state, The color of the powder is judged from the characteristics of the reflected light obtained by projecting the light. In this case, the light projection onto the filter paper after the reflected light has reached the steady state may be carried out in the air flow as it is, or may be taken out from the air flow outside the air flow.

On the other hand, the above-mentioned color measuring device includes at least one light projector that projects light on a filter paper that adsorbs powder in the air stream, at least one light receiver that receives reflected light from the filter paper due to this light projection, and powder in the air stream. Steady-state determination means that determines whether the reflected light from the filter paper that is adsorbing the body is in the steady state, and the steady-state determination means that determines the reflected light from the filter paper after the reflected light is in the steady state. And a powder color judging means for judging the color of the powder by obtaining the characteristics from the output of the light receiver. In this case, the powder color determination means may be connected to a light receiver for steady state determination, or the light projector and the light receiver may be directed toward the filter paper taken out from the airflow to detect light received outside the airflow. It may be connected to a container.

(Operation) In the case of the above color measuring method, while the reflected light from the filter paper is changing, there is an influence of the reflection by the filter paper itself, and the reflected light after the reflected light becomes the steady state is powder. Therefore, the hue, lightness, or saturation of only the powder can be seen by observing the characteristics of the reflected light from the light projected after the steady state.

Further, in the case of the color measurement device, the steady state determination means, the reflected light is steady when the output from the light receiver becomes substantially constant,
In other words, it is determined that it is possible to measure the color of only the powder without the influence of the filter paper itself, and the powder color determination means determines the color of the powder, that is, the hue, the brightness, or the saturation based on the output characteristics from the light receiver. To judge.

(Effect) According to the method of measuring the color of the powder in the air flow, the color is measured after the reflected light from the filter paper in the air flow reaches a steady state,
The color of the powder in the airflow can be known without being affected by the reflection of the filter paper itself. Even when the properties of the powder in the air flow change, it is not necessary to individually determine the amount of powder collected according to the properties, and always keep the minimum amount required for the properties adhered to the filter paper. Color measurement can be performed without error and in a short time, and the measurement result can be easily used. Then, by observing the color of the powder, that is, the hue, the brightness, or the saturation, it becomes possible to know the type of the powder, the amount of the specific component in the powder, and the like.

Further, according to the color measuring apparatus for powder in airflow, the above-mentioned color measuring method can be implemented, and there is actually no error because the output change from the light receiver of the reflected light during powder adsorption is observed. The time when the color can be measured can be easily and in the minimum necessary time according to the properties of the powder, and by linking the steady state determination means and the powder color determination means,
It is possible to know the color of the powder in the airflow in a short time, and it is easy to use the measurement result.

(Example) Hereinafter, the Example of this invention is described based on drawing. This example uses the present invention to measure the powder in exhaust gas from coal combustion, that is, the color of ash, and thus to measure the unburned content in ash, and the overall configuration is shown in FIG. There is.

That is, in the figure, 1 is a first cell for introducing the above-mentioned exhaust gas, and the exhaust gas is introduced by a vacuum pump (not shown) from the introduction port 1a at the upper end of the cell and discharged from the discharge port 1b. . A slit 3 is formed in the first cell 1 in the transverse direction for interposing a filter paper 2 across the flow of exhaust gas, and the slit 3 is provided with the filter paper 2
Sealing means 4 is provided to keep the cell 1 airtight and prevent light from leaking. In this case, filter paper 2
Is a filter paper roll 5 to a roller 6 provided on one side of the first cell 1.
It is supplied to the first cell 1 through the second cell 7 for traversing the second cell 7 for measuring the powder color, and is wound around the filter paper winding roll 9 through the roller 8. An output shaft of a motor (not shown) is linked to the filter paper winding roll 9.

Now, in the first cell 1, first, a heater 10 is provided on the wall between the edge of the exhaust gas inlet 1a and below the filter paper insertion position. Then, the filter paper 2 is placed above the filter paper insertion position.
A first light projector 11 that projects light onto the filter paper 2 and a first light receiver 12 that receives reflected light from the filter paper 2 generated by this light projection are arranged toward the filter paper 2. A temperature sensor 13 that detects the internal temperature of the first cell is provided above the filter paper insertion position, and a pressure sensor 14 that detects the pressure of the first cell 1 on the downstream side of the filter paper is provided below the filter paper insertion position. ing.

On the other hand, the second cell 7 is basically a closed type, but the first cell
The second light projector 17 is provided with a slit 15 similar to the cell 1 and a sealing means 16 for preventing light leakage in the slit 15, and projects light onto the filter paper 2 above the filter paper insertion position.
The second light receiver 18 which receives the reflected light from the filter paper 2 generated by this light projection is arranged toward the filter paper 2.

Thus, the sealing means 4, 16, the first and second light receivers 12, 18, the temperature sensor 13 and the pressure sensor 1
4 is connected to the control device 20. That is, the second
As shown in the figure, the control device 20 includes a steady state determination means 2
1, powder color determination means 22, temperature control means 23, data output means 24, and operating section (actuator) control means 2
It is equipped with 5.

In this case, the steady-state determination means 21 receives the output from the first light receiver 12 and the output from the pressure sensor 14, and the reflected light from the filter paper 2 of the first cell 1 is changed by the change with time of both outputs.
It is determined whether or not a steady state is reached during the process in which ash is adsorbed on. That is, when the ash in the exhaust gas is adsorbed on the filter paper 2, the influence of the reflection by the filter paper 2 itself becomes smaller according to the amount of adhesion, and the intensity of the reflected light from the filter paper 2 decreases. Along with that, the output of the first photodetector 12 decreases as shown in FIG. Therefore, if the ash adsorption continues, at the time T when the output of the first light receiver 12 becomes substantially constant, the entire surface of the filter paper 2 of the first cell 1 is covered with ash, and the influence of the reflection of the filter paper itself is exerted. It can be judged that there was no light and the reflection was only due to ash. However, when the amount of ash in the exhaust gas decreases due to factors such as trouble on the combustion side or the sampling line, and the ash adheres to the filter paper 2 temporarily, the reflected light is affected by the filter paper 2 itself. Nevertheless, the output of the first light receiver 12 becomes substantially constant, but in this case, the pressure on the downstream side of the filter paper does not decrease any more because the ash adhesion has stopped, and shows a constant value.
Therefore, when the pressure shows a constant value from the output from the pressure sensor 14, it is determined that the ash deposition is stopped and the steady state is not reached.

The steady state determination means 21 of the present embodiment is configured to determine the steady state when the output from the first light receiver 12 is constant and the output from the pressure sensor 14 is decreasing. .

By the way, in the case of Saxon Bell charcoal combustion ash, as shown in FIG. 6, when the unburned content is a little over 10%, the ash is 3 against the filter paper 2.
If more than mg / cm ^{2 is} attached, the degree of contamination will be saturated and the output from the first light receiver 12 will be constant.

The operating unit control means 25 operates upon receipt of the determination of the steady state from the steady state determination means 21, outputs a seal release signal to the sealing means 4 and 16, and also drives the filter paper winding motor 2
A winding command is output to 6, and the filter paper portion where the reflected light becomes steady is sent to the second cell 7, and a winding stop signal is sent to the motor 2 described above.
6 and the sealing operation signal to the sealing means 4 and 16, and further, the steady state judging means 21 and the powder color judging means 2 are output.
Issue an operation command to 2.

The powder color judging means 22 receives the output from the second light receiver 18, and from the output, catches the characteristic of the reflected light from the filter paper 2 after the steady state, that is, the ash color ( In the case of the present embodiment, the lightness) is determined, the amount of unburned matter in ash is obtained from the color of ash, and the data output means 24 is sent. That is, the intensity of the reflected light (brightness) of the second light receiver 18
The powder color judging means 22 judges the brightness of the ash from this output, and the brightness of the ash shown in FIG. 4 stored in advance (corresponding to the output of the second light receiver 18 as it is). The ratio of unburned ash content is calculated from the correlation data between ash and unburned ash content.

In this case, as shown in FIG. 5, in various combustion ash, there is a correlation between the pollution degree (the output of the second light receiver 18, that is, the reverse value of the lightness) and the unburned content, and each combustion ash is burned. By storing the correlation data corresponding to the ash, the amount of unburned matter in the ash can be obtained.

The temperature control means 23 receives the output from the temperature sensor 13 and operates the heater 10 to control the ambient temperature of the filter paper 2 of the first cell 1 and its surroundings to about 100 ° C.

Therefore, in the case of the above embodiment, first, the first cell 1 and the filter paper 2
The first light receiver 12 receives the reflected light from the filter paper 2 generated by the light projected by the first light projector 11 while introducing the exhaust gas, and the output from the first light receiver 12 and the output from the pressure sensor 14 are used. Therefore, the steady state of the reflected light is determined, and even when the introduction of ash is temporarily stopped, it is possible to know the time when the ash adheres in a sufficient amount for color measurement. Further, since the temperature inside the first cell 1 is controlled to about 100 ° C., the moisture in the exhaust gas is prevented from adhering to the filter paper 2, and the measurement error due to the moisture is avoided.

Then, after the judgment of the steady state, the portion of the filter paper 2 to which the ash adheres is sent to the second cell 7, and the color of the ash is different from that of the first light receiver 12 and the second projector 17 and the second projector 17 which are not contaminated by the exhaust gas. With the two light receivers 18, the powder color judging means 22 makes a judgment on the basis of the output of the second light receiver 18, so that it is possible to accurately measure the ash color. Then, the measurement result is fed back to the combustion device side of the coal as combustion data to control the combustion condition while monitoring the unburned matter in the ash, and the unburned matter amount can be reduced. Especially, in this case, the filter paper 2 is sequentially supplied to measure the color of the ash, that is, the unburned content in the ash, and the data is output to enable substantially continuous measurement, and the measurement result is displayed. It becomes easy to reflect on the combustion equipment side. By the way, in the past, it was calculated from the ignition loss of the ash that recovered the unburned matter in the ash, but since it is a manual analysis, it takes 1-2 hours at the earliest to obtain the measurement result, It was difficult to reflect.

Further, in the case of the above-mentioned embodiment, it is also possible to control the color of ash by controlling the combustion conditions so that it can be used as a cement admixture, for example.

Although the above examples relate to the measurement of the color of ash in the exhaust gas, it is needless to say that the present invention can be used for the measurement of the color of powder in other air streams.

Further, in the above embodiment, the determination of the steady state and the determination of the powder color are performed in different cells, but the output from the first light receiver 12 of the first cell 1 is used for the determination of the powder color. You may do it.

Further, in determining the powder color, the type of the light receiver may be changed to determine the hue, or the saturation may be determined, or a plurality of light receivers may be arranged to determine the hue from each output, The lightness and the saturation may be judged individually at the same time, or a light receiver capable of simultaneously detecting these three may be used.

Further, in the above embodiment, the output characteristic of the pressure sensor is used together with the reflected light for the determination of the steady state, but instead of this pressure sensor, a sensor for detecting the force acting on the filter paper by the vacuum pump is used. Good.

In addition, a plurality of projectors and light receivers of each system provided in the first cell and the second cell may be provided as a group.

Incidentally, although the so-called optical sensor is used in the present invention, it is possible to determine the steady state by the output of the pressure sensor described in the embodiment or the output of the sensor that detects the force acting on the filter paper.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a color measuring device for powder in air flow, FIG. 2 is a control system diagram, FIG. 3 is an output characteristic diagram of a first light receiver, and FIG.
The figure is a graph showing the relationship between the output of the second photoreceiver and the unburned ash content. Fig. 5 is a graph showing the relationship between the unburned ash content and the degree of contamination. Fig. 6 is the adhesion of ash to the filter paper. It is a graph which shows the relationship between quantity and pollution degree. 1 ... 1st cell, 2 ... filter paper, 7 ... 2nd cell, 11 ...
...... First light projector, 12 ...... First light receiver, 17 ...... Second light projector, 18 ...... Second light receiver, 20 ...... Control device, 21 ......
Steady state judging means, 22 ... Powder color judging means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Fujii, 1-1 Kawasaki-cho, Akashi-shi, Hyogo Prefecture Kawasaki Heavy Industries, Ltd. Technical Research Institute (56) Reference JP-A-47-28994 (JP, A) JP-A-SHO 54-27486 (JP, A) JP-A-60-22647 (JP, A) JP-A-57-184953 (JP, A)

Claims (4)

[Claims] 1. While adsorbing the powder in the air flow onto a filter paper, the change with time of the reflected light generated by the projection of the filter paper is measured, and after the reflected light reaches a steady state, the light is projected onto the filter paper. A method for measuring the color of powder in an air stream, which comprises determining the color of the powder from the characteristics of the reflected light obtained by. 2. At least one light projector that projects light onto a filter paper that adsorbs powder in an air stream, at least one light receiver that receives reflected light from the filter paper due to this projection, and adsorbs powder in an air stream. Steady-state determination means that determines whether the reflected light from the inside filter paper is in the steady state or not by the output change from the receiver, and the characteristics of the reflected light from the filter paper after the reflected light is in the steady state are received. An apparatus for measuring the color of powder in an air flow, comprising: a powder color judging means for judging the color of powder obtained from the output of the container. 3. The projector and the light receiver are directed to a filter paper insertion position in the air flow, and the steady state judging means and the powder color judging means are connected to the light receiver. Item 6. A color measuring device for powder in an air stream according to item. 4. A first and a second system of projectors, and a first projector.
And a second light receiver of two systems, the first light projector and the first light receiver are directed to the insertion position of the filter paper in the air stream, and the second light emitter and the second light receiver take out the filter paper outside the air stream. The powder in airflow according to claim 2, wherein the steady state determination means is connected to the first light receiver, and the powder color determination means is connected to the second light receiver. Color measuring device.