JP4347237B2 - Fuel ratio measuring apparatus and method - Google Patents

Description

The present invention is, for example, to determine the ignition degree of the pulverized coal in the pipe for supplying the boiler pulverized coal-fired power plant, to a fuel ratio measuring apparatus and a method for measuring the properties of the pulverized coal.

  For example, in a thermal power plant, for the purpose of reducing the cost of pulverized coal as a fuel, pulverized coal is produced by using coal from various production areas, so the quality of the pulverized coal is not uniformized. Therefore, when supplying pulverized coal to a boiler, it is necessary to specify the properties of the pulverized coal, that is, the fuel ratio to ensure combustion stability in the boiler.

  Conventionally, boiler temperature is controlled by controlling the temperature of the boiler and the temperature of the mill that turns coal into pulverized coal. However, boiler temperature control and mill temperature control are based on past information. Because of the control, there is a desire to confirm the properties of pulverized coal immediately before being supplied to the boiler in real time.

  Therefore, there is one described in Patent Document 1 below that detects the fuel ratio of pulverized coal supplied to the boiler in real time. The fuel ratio measuring device and method described in Patent Document 1 irradiate a pipe for supplying pulverized coal with a laser beam, and Raman scattered light from fixed carbon in pulverized coal and Raman scattered light from C—H bonds. And the fuel ratio is obtained based on each detected scattered light.

JP 2003-270150 A

  In the fuel ratio measuring apparatus and method of Patent Document 1 described above, the fuel ratio of pulverized coal is obtained based on Raman scattered light from pulverized coal using laser light. In this case, since the laser beam is irradiated to the fuel (pulverized coal), there is a possibility of ignition depending on the oxygen concentration in the pipe, and this point needs to be fully considered.

The present invention has been made to solve such a problem, and an object thereof is to provide a fuel ratio measuring apparatus and method with improved safety.

  In order to achieve the above-mentioned object, a fuel ignition determination apparatus according to claim 1 is directed to a light irradiation means for irradiating light flowing in a pipe to light crossing the flow direction, and from the light irradiation means to fuel particles. A photodetector for detecting scattered light of the irradiated light; a concentration detecting means for obtaining a fuel concentration based on the intensity of the scattered light detected by the photodetector; and a fuel concentration detected by the concentration detecting means. And an ignition degree determining means for determining the degree of ignition of the fuel.

  In the fuel ignition determination apparatus according to the invention of claim 2, the light detector detects scattered light of light irradiated to the pulverized coal from the light irradiation means as a distribution state along a radial direction of the pipe, and the concentration The detection means is characterized in that the concentration of pulverized coal is obtained based on the intensity distribution of scattered light distributed along the radial direction of the pipe.

  According to a third aspect of the present invention, there is provided a fuel ignition determination method that irradiates light flowing in a pipe with light that intersects the flow direction, detects scattered light of light irradiated to fuel particles, and detects the detected scattering. The fuel concentration is obtained based on the light intensity, and the ignition degree of the fuel is determined based on the fuel concentration.

  Further, the fuel ratio measuring device of the invention of claim 4 irradiates a pipe through which pulverized coal flows with laser light, Raman scattered light from fixed carbon in pulverized coal, and Raman scattering from C—H bond. In a fuel ratio measuring device that detects fluorescence of light or hydrocarbons and obtains a fuel ratio based on the ratio of detected Raman scattered light from fixed carbon to Raman scattered light from C—H bonds or hydrocarbon fluorescence A light irradiation means for irradiating light intersecting the flow direction toward the pulverized coal flowing in the pipe, and a photodetector for detecting scattered light of the light irradiated to the pulverized coal from the light irradiation means, Concentration detection means for determining the concentration of pulverized coal based on the intensity of scattered light detected by the photodetector, and an ignition degree determination means for determining the ignition degree of pulverized coal based on the pulverized coal concentration detected by the concentration detection means And the ignition degree judging means It is characterized in that and control means for controlling the irradiation intensity of the laser light based on the ignition degree of the pulverized coal.

  In the fuel ratio measuring device of the invention of claim 5, the light irradiating means can irradiate the pipe with a planar light that intersects the flow direction of the pulverized coal, and the photodetector is the planar light source. Scattered light can be detected, and the concentration detecting means obtains the concentration of pulverized coal based on the intensity distribution of the planar scattered light.

  In the fuel ratio measuring device of the invention of claim 6, the light detector detects scattered light of light irradiated to the pulverized coal from the light irradiation means as a distribution state along a radial direction of the pipe, and the concentration The detection means is characterized in that the concentration of pulverized coal is obtained based on the intensity distribution of scattered light distributed along the radial direction of the pipe.

  In the fuel ratio measuring device according to the seventh aspect of the invention, the photodetector includes a plurality of light beams arranged in a straight line such that the input ends are concentrically arranged and the output end on the outer peripheral side is an upper portion or a lower portion. A fiber bundle, and detecting scattered light of light irradiated to the pulverized coal from the light irradiation means as a distribution state along a radial direction of the pipe by the optical fiber bundle, and the concentration detection means It is characterized in that the concentration of pulverized coal is obtained based on the intensity distribution of scattered light distributed along the radial direction.

  In the fuel ratio measuring device according to an eighth aspect of the present invention, the light irradiating means is capable of irradiating light whose light density increases toward the tip toward the pulverized coal in the pipe.

  The fuel ratio measuring method of the invention of claim 9 irradiates a pipe through which pulverized coal flows with laser light, and detects Raman scattered light from fixed carbon in pulverized coal and Raman scattered light from C—H bonds. In the fuel ratio measuring method for detecting and detecting the fuel ratio based on the ratio of the Raman scattered light from the detected fixed carbon and the Raman scattered light from the C—H bond or the fluorescence of hydrocarbons, the fuel flows in the pipe. Irradiate light that crosses the flow direction toward the pulverized coal, detect the scattered light of the light irradiated to the pulverized coal, determine the concentration of the pulverized coal based on the intensity of the detected scattered light, this pulverized coal The ignition degree of pulverized coal is determined based on the concentration, and the irradiation intensity of the laser beam is controlled based on the ignition degree.

  According to the fuel ignition determination device of the first aspect of the present invention, the light irradiation means for irradiating light toward the fuel flowing in the pipe, and the scattered light of the light irradiated to the fuel particles from the light irradiation means are detected. Light detector, concentration detection means for determining the concentration of fuel based on the intensity of scattered light detected by the light detector, and ignition degree determination for determining the degree of fuel ignition based on the fuel concentration detected by the concentration detection means Therefore, it is possible to easily determine the ignition degree of the fuel based on the fuel concentration with a simple configuration, and to improve the safety.

  According to the fuel ignition determination device of the second aspect of the invention, the photodetector detects the scattered light of the light irradiated to the pulverized coal from the light irradiation means as a distribution state along the radial direction of the pipe, and the concentration detection means Since the concentration of pulverized coal is determined based on the intensity distribution of scattered light distributed along the radial direction of the pipe, the possibility of ignition of the pulverized coal flowing through the pipe can be grasped as a distribution along the radial direction. It is possible to improve the accuracy of determining the degree of ignition of pulverized coal.

  According to the fuel ignition determination method of the invention of claim 3, the fuel flowing in the pipe is irradiated with light, the fuel concentration is determined based on the intensity of the scattered light, and the ignition degree of the fuel is determined based on the fuel concentration. Since it did, it can determine the ignition degree of a fuel easily based on fuel concentration, and can improve safety | security.

  According to the fuel ratio measuring device of the invention of claim 4, the fuel ratio is based on the ratio of the Raman scattered light from the fixed carbon in the pulverized coal and the Raman scattered light from the C—H bond or the fluorescence of the hydrocarbon. A light irradiating means for irradiating light toward the pulverized coal flowing in the pipe, a light detector for detecting scattered light from the light irradiated to the pulverized coal, and a light Concentration detection means for determining the concentration of pulverized coal based on the intensity of scattered light detected by the detector, and ignition degree determination means for determining the ignition degree of pulverized coal based on the pulverized coal concentration detected by the concentration detection means Since the control means controls the irradiation intensity of the laser light based on the ignition degree of the pulverized coal determined by the ignition degree determining means, the fuel ratio can be obtained in real time during the delivery of the pulverized coal. Determine the degree of ignition of pulverized coal, By controlling the irradiation intensity of the laser beam for obtaining the postal ratio can grasp the firing of pulverized coal in advance, as a result, it is possible to improve safety.

  According to the fuel ratio measuring apparatus of the fifth aspect of the invention, the light irradiation means can irradiate the pipe with the planar light that intersects the flow direction of the pulverized coal, and the light detector scatters the planar light. Since the light can be detected and the concentration detection means obtains the concentration of the pulverized coal based on the intensity distribution of the surface scattered light, it is possible to spatially grasp the possibility of the pulverized coal flowing through the pipe. It is possible to improve the accuracy of determining the degree of ignition of pulverized coal.

  According to the fuel ratio measuring apparatus of the invention of claim 6, the photodetector detects the scattered light of the light irradiated to the pulverized coal from the light irradiation means as a distribution state along the radial direction of the pipe, and the concentration detection means Since the concentration of pulverized coal is determined based on the intensity distribution of scattered light distributed along the radial direction of the pipe, the possibility of ignition of the pulverized coal flowing through the pipe can be grasped as a distribution along the radial direction. It is possible to improve the accuracy of determining the degree of ignition of pulverized coal.

  According to the fuel ratio measuring apparatus of the seventh aspect of the invention, the photodetector includes a plurality of light detectors arranged linearly so that the input ends are concentrically arranged and the output ends on the outer peripheral side are upper or lower. It has an optical fiber bundle, and the scattered light of the light irradiated to the pulverized coal from the light irradiating means is detected as a distribution state along the radial direction of the pipe by the optical fiber bundle, and the concentration detecting means is along the radial direction of the pipe. Since the concentration of pulverized coal is determined based on the intensity distribution of scattered light distributed in this way, the possibility of ignition of the pulverized coal flowing through the pipe can be grasped as a distribution along its radial direction. The degree determination accuracy can be improved.

  According to the fuel ratio measuring apparatus of the eighth aspect of the invention, the light irradiating means can irradiate the light whose light density increases toward the tip toward the pulverized coal in the pipe, so the density of the light irradiated into the pipe Is changed along the radial direction, the attenuation of light can be suppressed and scattered light can be reliably detected.

  According to the fuel ratio measuring method of the invention of claim 9, the fuel ratio is calculated based on the ratio of the Raman scattered light from the fixed carbon in the pulverized coal and the Raman scattered light from the C—H bond or the fluorescence of the hydrocarbon. The pulverized coal flowing through the pipe is irradiated with light, the concentration of the pulverized coal is obtained based on the intensity of the scattered light of the light irradiated to the pulverized coal, and the pulverized coal is determined based on the pulverized coal concentration. Since the degree of ignition of the pulverized coal is controlled by controlling the irradiation intensity of the laser light, the fuel ratio can be obtained in real time while the pulverized coal is being fed, and the degree of ignition of the pulverized coal is determined and the fuel ratio is determined. By controlling the irradiation intensity of the laser beam for obtaining the above, it is possible to grasp the ignition of pulverized coal in advance, and as a result, it is possible to improve safety.

  Embodiments of a fuel ignition determination device and method and a fuel ratio measurement device and method according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  FIG. 1 is a schematic configuration diagram of a fuel ratio measuring device to which a fuel ignition determination device according to Embodiment 1 of the present invention is applied.

  In Example 1, as shown in FIG. 1, the fuel ratio measuring device 11 is provided along a pipe P for supplying pulverized coal F as fuel to a boiler (not shown), and the fuel ratio of the pulverized coal F is determined. It is to be measured. In this fuel ratio measuring device 11, a laser device 13 is accommodated in a housing 12, and this laser device 13 irradiates a laser beam L to a pipe P in which pulverized coal F flows. In this case, a laser passage 14 and an opening / closing valve 15 are provided between the housing 12 and the pipe P, and the laser light L emitted from the laser device 13 flows through the pipe P through the laser path 14. Irradiation is performed in a direction substantially perpendicular to the flow direction of the pulverized coal F. Although not shown, purge air can be supplied to the laser passage 14.

  Further, a photodetector 16 is accommodated in the housing 12 adjacent to the laser device 13, and this photodetector 16 is composed of Raman scattered light from fixed carbon in pulverized coal and C—H bonds. It is possible to detect and detect Raman scattered light or hydrocarbon fluorescence. That is, a beam splitter 17 is provided between the laser device 13 and the laser path 14, and a filter 18 is provided between the photodetector 16 and the beam splitter 17. Then, the fuel ratio calculation unit 19 obtains the fuel ratio based on the ratio between the Raman scattered light from the fixed carbon detected by the photodetector 16 and the Raman scattered light from the C—H bond or the fluorescence of the hydrocarbon. Can do.

  That is, pulverized coal F is a hydrocarbon (HC) that is mostly low in carbon and easily volatilized as a gas, with volatile matter being C (carbon) and H (hydrogen). In addition, silicon (Si), aluminum (Al), and the like are included. That is, when the wavelength of the laser light L oscillated from the laser device 13 is 532 nm, the wavelength of Raman scattered light from fixed carbon is around 570 nm, and the wavelength of Raman scattered light 16 from C—H bond is around 630 nm. Can be measured, and the fuel ratio can be obtained from the ratio of the fixed carbon content to the volatile content.

  On the other hand, the ignition determination device 21 is provided adjacent to the fuel ratio measuring device 11 along the pipe P for supplying the pulverized coal F, and determines the degree of ignition of the pulverized coal F. In this ignition determination device 21, a laser device 23 as a light irradiation means is accommodated in a housing 22, and this laser device 23 irradiates a laser beam L to a pipe P in which pulverized coal F flows. It is. In this case, a laser passage 24 and an opening / closing valve 25 are provided between the housing 22 and the pipe P, and the laser light L emitted from the light emitting element 23a of the laser device 23 passes through the laser path 24 and is piped. Irradiation is performed in a direction substantially perpendicular to the flow direction of the pulverized coal F flowing in P. Although not shown, purge air can be supplied to the laser passage 24.

  In addition, a photodetector 26 is accommodated in the housing 22 adjacent to the laser device 23, and a light receiving element 26a of the photodetector 26 can receive and detect scattered light from pulverized coal. It has become. The concentration calculation unit (concentration detection means) 27 can estimate the concentration of pulverized coal based on the intensity of scattered light detected by the photodetector 26. Further, the ignition degree determination unit 28 can determine the ignition degree of the pulverized coal F based on the pulverized coal concentration estimated by the concentration calculation unit 27. That is, the ignition degree determination unit 28 determines whether or not the pulverized coal concentration estimated by the concentration calculation unit 27 is in a preset ignition region concentration.

In this case, although the laser device 23 as the light irradiation means is applied, the light incident on the pulverized coal F is not limited to the laser light L, but the shorter the wavelength of the light, the more likely the scattered light is generated. If it is set smaller than the particle size of pulverized coal F (about 70 microns), the effect of scattering is great. Further, since the wavelength of the scattered light hardly changes, the influence of disturbance light can be eliminated by receiving light in the vicinity of the same wavelength as the incident light. And the relationship between the density | concentration of pulverized coal F, the intensity | strength of scattered light, and an ignition area | region (ignition degree) should be investigated beforehand, and the intensity | strength of the scattered light which the photodetector 26 detected should just be converted into pulverized coal density | concentration. For pulverized coal F, if the oxygen concentration is constant, the area of the pulverized coal concentration 100g / m ³ ~1800g / m ³ is ignited area density.

  The control unit (control means) 30 can control the fuel ratio measurement device 11 and the ignition determination device 21 described above. When the ignition degree determination unit 28 of the ignition determination device 21 determines that the current pulverized coal concentration has approached a preset ignition region concentration, the control unit 30 starts from the laser device 13 of the fuel ratio measurement device 11. The irradiation intensity of the laser beam is controlled, for example, the irradiation of the laser beam L is stopped. In addition, when the ignition degree determination part 28 of the ignition determination apparatus 21 determines with the present pulverized coal density | concentration approaching the preset ignition region density | concentration, you may make it stop supply of pulverized coal F. FIG.

  As described above, in the fuel ratio measurement device 11 and the ignition determination device 21 according to the first embodiment, the laser device 23 that irradiates the laser light L toward the pulverized coal F flowing in the pipe P, and the laser device 23. A photodetector 26 for detecting scattered light of the laser light L irradiated to the pulverized coal F, a concentration calculating unit 27 for determining the concentration of the pulverized coal F based on the intensity of the scattered light detected by the photodetector 26, and An ignition degree determination unit 28 that determines the ignition degree of the pulverized coal F based on the pulverized coal concentration detected by the concentration calculation unit 27 is provided, and the ignition degree determination unit 28 determines that the current pulverized coal concentration approaches the ignition region concentration. When the determination is made, the control unit 30 stops the laser device 13 of the fuel ratio measuring device 11.

  Accordingly, the fuel ratio measuring device 11 can obtain the fuel ratio in real time during the delivery of the pulverized coal F, and the ignition determination device 21 determines the ignition degree of the pulverized coal, and the current pulverized coal concentration is ignited. When the region concentration is approached, the laser device 13 of the fuel ratio measuring device 11 is stopped, whereby the ignition of the pulverized coal F can be grasped in advance, and as a result, the safety can be improved.

  FIG. 2 is a schematic configuration diagram of a fuel ratio measuring apparatus according to Embodiment 2 of the present invention, and FIG. 3 is a graph showing a laser output switching operation depending on the type of pulverized coal. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 2, the fuel ratio measuring device of the second embodiment is provided along a pipe P that supplies pulverized coal F, and has a fuel ratio measuring function and a fuel ignition determination function. In the fuel ratio measuring apparatus according to the second embodiment, the laser device 31 serving as the light irradiation unit emits a planar laser beam L that intersects the flow direction of the pulverized coal F to the pipe P through which the pulverized coal F flows. Can be irradiated. The CCD camera 32 as a photodetector can detect and detect planar scattered light from pulverized coal through a filter 33. In this case, the CCD camera 32 can receive light by spectroscopically analyzing the Raman scattered light from the fixed carbon in the pulverized coal and the Raman scattered light from the C—H bond or the fluorescence of the hydrocarbon by the filter 33.

  The fuel ratio calculation unit 34 obtains the fuel ratio based on the ratio of the Raman scattered light from the fixed carbon detected by the CCD camera 32 and the Raman scattered light from the C—H bond or the hydrocarbon fluorescence. it can.

  On the other hand, the concentration calculation unit (concentration detection means) 35 can estimate the concentration of pulverized coal based on the intensity distribution of the planar scattered light detected by the CCD camera 32. Further, the ignition degree determination unit 36 can determine the ignition degree of the pulverized coal F based on the pulverized coal concentration estimated by the concentration calculation unit 35. That is, the ignition degree determination unit 36 determines whether or not the pulverized coal concentration estimated by the concentration calculation unit 35 is in a preset ignition region concentration. In this case, the CCD camera 32 detects planar scattered light, and the concentration calculation unit 35 estimates the concentration of pulverized coal based on the intensity distribution of the planar scattered light. The ignition degree of the pulverized coal F is determined in all the regions in the cross-sectional direction.

  The control unit (control means) 37 controls the irradiation intensity of the laser light from the laser device 31 when the ignition degree determination unit 36 determines that the current pulverized coal concentration has approached a preset ignition region concentration.

That is, when supplying the pulverized coal F as fuel to the boiler through the pipe P, the type of the pulverized coal F is switched according to the combustion state of the boiler. That is, as shown in FIG. 3, at time t ₀ , the supply ratio of high-fuel ratio coal is 100%, and the supply ratio of low-fuel ratio coal is 0%. From this state, the supply ratio of high-fuel ratio coal is gradually decreased, while the supply ratio of low-fuel ratio coal is gradually increased. In general, low-fuel coal is more likely to ignite because it contains more volatile matter than high-fuel coal. Therefore, the output level of laser light when supplying high-fuel ratio coal is set to high level A, the output level of laser light when supplying low-fuel ratio coal is set to low level B, and the supply ratio of low-fuel ratio coal is switched to a predetermined level. When the threshold value is exceeded, the laser light output level is switched from the high level A to the low level B.

  That is, the relationship between the supply ratio of the low-fuel ratio coal and the concentration of the pulverized coal F is examined in advance, and the ignition degree determination unit 36 corresponds to the supply ratio (switching threshold) of the current pulverized coal concentration. When it is determined that the density is present, the irradiation intensity of the laser beam from the laser device 31 is switched from the high level A to the low level B.

  As described above, in the fuel ratio measuring apparatus according to the second embodiment, the surface from the pulverized coal through the filter 33 and the laser device 31 that irradiates the planar laser beam L toward the pipe P through which the pulverized coal F flows. A CCD camera 32 that receives and detects the scattered light, a concentration calculation unit 35 that estimates the concentration of pulverized coal based on the intensity distribution of the planar scattered light detected by the CCD camera 32, and a concentration calculation unit 35 An ignition degree determination unit 36 that determines the ignition degree of the pulverized coal F based on the pulverized coal concentration is provided, and when the ignition degree determination unit 36 determines that the current pulverized coal concentration has approached the ignition region concentration, the control unit 37. Adjusts the irradiation intensity of the laser device 31.

  Therefore, when the ignition degree determination unit 36 determines that the current pulverized coal concentration is at a concentration corresponding to the supply ratio (switching threshold value) of the high-fuel ratio coal and the low-fuel ratio coal, the irradiation intensity of the laser light from the laser device 31 is determined. Is switched between the high level A and the low level B, and the ignition of the pulverized coal F can be grasped in advance, and as a result, the safety can be improved. In this case, the possibility of ignition of the pulverized coal F flowing through the pipe P can be spatially grasped, and the determination accuracy of the degree of ignition of the pulverized coal F can be improved.

  FIG. 4 is a schematic configuration diagram of a fuel ratio measuring device according to a third embodiment of the present invention, and FIG. 5 is an explanatory diagram showing a light receiving state of scattered light in the fuel ratio measuring device of the third embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 4, the fuel ratio measuring device of the third embodiment is provided along a pipe P that supplies pulverized coal F, and has a fuel ratio measuring function and a fuel ignition determination function. In the fuel ratio measuring device of the third embodiment, the laser device 41 as the light irradiating means can irradiate the pipe P in which the pulverized coal F flows through the input optical fiber 42 with the laser light L. That is, the laser beam L output from the input optical fiber 42 is irradiated to the pipe P through the mirror 43. Further, a mirror 44 is provided between the mirror 43 and the pipe P, and the scattered light from the pulverized coal can be reflected almost at right angles and directed to the lens 45. The lens 45 collects scattered light scattered from the pulverized coal and reflected by the mirror 44. The collected scattered light is an optical fiber in which a plurality of output optical fibers are bundled in a circular shape. Light can enter the bundle 46. The optical fiber bundle 46 is changed from the circular shape to the planar shape in the arrangement direction of the output optical fibers.

  That is, when the pulverized coal F in the pipe P is irradiated with the laser light L from the laser device 41, the laser light L collides with the pulverized coal F and generates scattered light. In this case, a solid line in FIG. As shown, the scattered light generated by colliding with the pulverized coal F flowing in the upper part of the pipe P has a large spread angle and collides with the pulverized coal F flowing in the lower part of the pipe P as shown by the dotted line in FIG. The scattered light thus generated has a small spread angle. Therefore, the scattered light (solid line in FIG. 5) from the upper pulverized coal F in the pipe P enters the output optical fiber disposed outside the optical fiber bundle 46, and the lower pulverized coal F in the pipe P. The scattered light from the light enters an output optical fiber disposed on the center side of the optical fiber bundle 46. The optical fiber bundle 46 is changed from a circular shape to a planar shape in the arrangement direction of the output optical fibers. In this case, the output optical fiber on the center side of the circular optical fiber bundle 46 is located at the center portion and on the upper side. The output optical fiber is disposed in the upper part, and the lower output optical fiber is disposed in the lower part.

  Therefore, as shown in FIG. 4, scattered light output from a bundle of output optical fibers 46 arranged in a plane is input to a CCD camera 48 as a photodetector via a spectroscope 47. The CCD camera 48 detects the scattered light as a distribution state along the radial direction (vertical direction) of the pipe P.

  The CCD camera 48 can receive light by spectroscopically separating into Raman scattered light from fixed carbon in pulverized coal and Raman scattered light from C—H bonds or hydrocarbon fluorescence. The fuel ratio calculation unit 49 can obtain the fuel ratio based on the ratio between the Raman scattered light from the fixed carbon detected by the CCD camera 48 and the Raman scattered light from the C—H bond or the fluorescence of the hydrocarbon.

  On the other hand, the concentration calculation unit (concentration detection means) 50 can estimate the concentration of the pulverized coal F based on the intensity distribution of the scattered light along the radial direction of the pipe P detected by the CCD camera 48. Further, the ignition degree determination unit 51 can determine the ignition degree of the pulverized coal F based on the pulverized coal concentration estimated by the concentration calculation unit 50. That is, the ignition degree determination unit 51 determines whether the pulverized coal concentration estimated by the concentration calculation unit 50 is in a preset ignition region concentration. The pulverized coal F flowing in the pipe P has a larger particle diameter in the lower part than in the upper part of the pipe P. In this case, the CCD camera 48 detects scattered light along the radial direction of the pipe P, and the concentration calculation unit 50 estimates the concentration of pulverized coal based on the intensity distribution of the scattered light along the radial direction of the pipe P. The ignition degree determination unit 36 determines the ignition degree of the pulverized coal F in most regions in the cross-sectional direction of the pipe P.

  And the control part (control means) 52 controls the irradiation intensity | strength of the laser beam from the laser apparatus 41, when the ignition degree determination part 51 determines with the present pulverized coal density | concentration approaching the preset ignition area density | concentration. And reduce its output.

  As described above, in the fuel ratio measuring apparatus according to the third embodiment, the laser device 41 irradiates the laser beam L toward the pipe P through which the pulverized coal F flows, and the radial direction of the pipe P through the spectroscope 47. A CCD camera 48 that receives and detects scattered light from the distributed pulverized coal, a concentration calculation unit 50 that estimates the concentration of pulverized coal based on the intensity distribution of the scattered light detected by the CCD camera 48, and a concentration calculation unit 50 Is provided with an ignition degree determination unit 51 that determines the ignition degree of the pulverized coal F based on the estimated pulverized coal concentration, and when the ignition degree determination unit 51 determines that the current pulverized coal concentration has approached the ignition region concentration, The control unit 52 adjusts the irradiation intensity of the laser device 41.

  Therefore, when the ignition degree determination unit 51 determines the ignition degree of the pulverized coal F and the current pulverized coal concentration approaches the ignition region concentration, the ignition intensity of the laser device 41 is adjusted to ignite the pulverized coal F. As a result, the safety can be improved. In this case, the possibility of ignition of the pulverized coal F flowing in the pipe P can be grasped as a distribution along the radial direction, and the determination accuracy of the ignition degree of the pulverized coal F can be improved.

  FIG. 6 is a schematic configuration diagram of a fuel ratio measuring device according to a fourth embodiment of the present invention, and FIG. 7 is an explanatory diagram showing a light receiving state of scattered light in the fuel ratio measuring device of the fourth embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  In the fuel ratio measuring device of the fourth embodiment, as shown in FIGS. 6 and 7, the laser device 41 can irradiate the pipe P in which the pulverized coal F flows through the input optical fiber 42 with the laser light L. . In this case, the laser light L output from the input optical fiber 42 is diffused at a predetermined angle by the lens 61, reflected by the mirror 43 and irradiated into the pipe P, so that the laser light L in the pipe P is irradiated. The light density increases toward the pulverized coal F toward the tip.

  That is, the pulverized coal F flowing in the horizontal pipe P tends to ignite when the particle diameter is small, and tends to ignite when the particle diameter is small. Hateful. Therefore, by changing the energy density of the laser beam L accordingly, higher energy can be incident. The generated fluorescence / scattered light is proportional to the intensity of incident light. Since the intensity of incident light and the generated fluorescence / scattered light are attenuated according to the amount of pulverized coal F passing therethrough, the signal intensity that can be measured at the bottom of the pipe P becomes smaller. Therefore, attenuation is corrected by changing the density of incident light.

  Therefore, the laser light L irradiated toward the pulverized coal F in the pipe P has a light density higher toward the tip, so that the laser beam L having a lower energy density than the pulverized coal F having a small particle diameter and easily ignited. , And the high energy density laser beam L is irradiated to the pulverized coal F having a large particle diameter and difficult to ignite. And attenuation | damping can be correct | amended by irradiating the laser beam L of high energy density toward the pulverized coal F with small measurement signal intensity | strength which flows through the bottom part of the piping P. FIG.

  A mirror 44 is provided between the mirror 43 and the pipe P, and the scattered light from the pulverized coal is reflected almost at right angles toward the lens 45 and is scattered from the pulverized coal by the lens 45. Then, the scattered light reflected by the mirror 44 is collected. The collected scattered light can enter the optical fiber bundle 46 in which a plurality of output optical fibers are bundled in a circular shape.

  The configuration of the optical fiber bundle 46 and the configurations of the spectroscope 47, the CCD camera 48, the fuel ratio calculation unit 49, the concentration calculation unit 50, the ignition degree determination unit 51, and the control unit 52 are the same as those in the fourth embodiment. Since it is the same, description is abbreviate | omitted.

  As described above, in the fuel ratio measuring apparatus according to the fourth embodiment, the laser device 41 can irradiate the laser beam L to the pipe P in which the pulverized coal F flows through the input optical fiber 42 by the laser device 41. After being diffused at a predetermined angle by 61, the laser beam L is reflected by the mirror 43 and irradiated into the pipe P, so that the light density increases toward the pulverized coal F in the pipe P toward the tip. I have to.

  Therefore, by adjusting the energy density of the laser light L according to the particle diameter of the pulverized coal F flowing in the pipe P and the position of the pulverized coal F flowing in the pipe P, the ignition is suppressed and highly accurate detection is performed. Thus, it is possible to appropriately grasp the ignition of the pulverized coal F in advance, and as a result, it is possible to improve safety.

  FIG. 8 is a schematic configuration diagram of a fuel ratio measuring apparatus according to Embodiment 5 of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  In the fuel ratio measuring device of the fifth embodiment, as shown in FIG. 8, the laser device 41 irradiates the pipe P in which the pulverized coal F flows through the input optical fiber 42 and the mirror 43 with the laser light L. Can do. Then, after the scattered light from the pulverized coal F is reflected by the mirror 44 and collected by the lens 45, light can enter the optical fiber bundle 71 in which a plurality of output optical fibers are bundled in a circular shape.

  The optical fiber bundle 46 is changed from a circular shape to a planar shape in the arrangement direction of the output optical fibers, and a filter 72 is attached to the end portion. A photodetector 73 is provided opposite to each filter 72, and each photodetector 73 is connected to a signal processing device 75 via an AD converter 74. The signal processing device 75 is connected to the fuel ratio calculation unit 49 and the concentration calculation unit 50.

  Accordingly, the signal processing device 75 receives the scattered light output from the bundle of output optical fibers 71 arranged in a plane via the filter 72, the photodetector 73, and the AD converter 74, and a fuel ratio calculation unit. 49 calculates | requires the fuel ratio of the pulverized coal F, and the density | concentration calculation part 50 estimates the density | concentration of the pulverized coal F based on the intensity distribution of the scattered light along the radial direction of the piping P. FIG. The ignition degree determination unit 51 determines the ignition degree of the pulverized coal F based on the pulverized coal concentration. And the control part 52 controls the irradiation intensity | strength of the laser beam from the laser apparatus 41, when the ignition degree determination part 51 determines with the present pulverized coal density | concentration approaching the preset ignition area density | concentration, and the output Reduce.

  As described above, in the fuel ratio measuring apparatus according to the fifth embodiment, the scattered light from the pulverized coal distributed along the radial direction of the pipe P is filtered with the filter 72, the photodetector 73, the AD converter 74, and the signal processing. The intensity distribution of scattered light is obtained using the device 75. Therefore, the concentration of the pulverized coal F in the pipe P can be estimated at low cost without using a CCD camera or a spectroscope, and the structure can be simplified.

Engaging Ru fuel ratio measuring apparatus and method according to the present invention, to determine the ignition degree from the concentration of the fuel is intended to improve safety, fuel feed Kyusuru to fuel ratio measuring apparatus and a method that put the system Useful to apply.

1 is a schematic configuration diagram of a fuel ratio measurement device to which a fuel ignition determination device according to Embodiment 1 of the present invention is applied. It is a schematic block diagram of the fuel ratio measuring apparatus which concerns on Example 2 of this invention. It is a graph showing switching operation of the laser output by the kind of pulverized coal. It is a schematic block diagram of the fuel ratio measuring apparatus which concerns on Example 3 of this invention. It is explanatory drawing showing the light-receiving state of the scattered light in the fuel ratio measuring apparatus of Example 3. It is a schematic block diagram of the fuel ratio measuring apparatus which concerns on Example 4 of this invention. It is explanatory drawing showing the light-receiving state of the scattered light in the fuel ratio measuring apparatus of Example 4. It is a schematic block diagram of the fuel ratio measuring apparatus which concerns on Example 5 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Fuel ratio measurement apparatus 13 Laser apparatus 16 Photo detector 19, 34, 49 Fuel ratio calculation part 21 Ignition determination apparatus 23, 31, 41 Laser apparatus (light irradiation means)
26 Photodetector 27, 35, 50 Concentration calculation unit (concentration detection means)
28, 36, 51 Firing degree determination unit 30, 37, 52 Control unit (control means)
32, 48 CCD camera (photodetector)
F pulverized coal (fuel)
P piping

Claims (4)

Laser pipe is irradiated to the pipe where pulverized coal flows, and Raman scattered light from fixed carbon in pulverized coal and Raman scattered light from C—H bond or hydrocarbon fluorescence are detected, and this detected fixation In a fuel ratio measuring device for obtaining a fuel ratio based on a ratio of Raman scattered light from carbon and Raman scattered light from C—H bonds or fluorescence of hydrocarbons, the flow toward the pulverized coal flowing in the pipe Based on the light irradiation means for irradiating light intersecting the direction, the photodetector for detecting the scattered light of the light irradiated to the pulverized coal from the light irradiation means, and the intensity of the scattered light detected by the light detector Concentration detection means for determining the concentration of pulverized coal, ignition degree determination means for determining the ignition degree of pulverized coal based on the pulverized coal concentration detected by the concentration detection means, and ignition of pulverized coal determined by the ignition degree determination means Based on the degree And control means for controlling the irradiation intensity of light,
The photodetector has a plurality of optical fiber bundles arranged in a straight line so that the input ends are arranged concentrically and the output end on the outer peripheral side is at the top or the bottom. The scattered light of the light irradiated to the charcoal is detected as a distribution state along the radial direction of the pipe by the optical fiber bundle, and the concentration detection means is an intensity of the scattered light distributed along the radial direction of the pipe. A fuel ratio measuring device characterized in that the concentration of pulverized coal is obtained based on the distribution.   The fuel ratio measuring device according to claim 1, wherein the light irradiating means is capable of irradiating light whose light density increases toward the tip toward the pulverized coal in the pipe.   A laser beam is irradiated to a pipe through which pulverized coal flows, and Raman scattered light from fixed carbon in pulverized coal and Raman scattered light from C—H bond are detected, and Raman scattering from the detected fixed carbon is detected. In a fuel ratio measurement method for obtaining a fuel ratio based on a ratio between light and Raman scattered light from C—H bonds or hydrocarbon fluorescence, light crossing the flow direction toward pulverized coal flowing in the pipe A plurality of optical fiber bundles arranged in a straight line so that the input end is arranged concentrically and the output end on the outer peripheral side is at the top or bottom. To detect the distribution state along the radial direction of the pipe, determine the concentration of the pulverized coal based on the intensity distribution of the detected scattered light, determine the ignition degree of the pulverized coal based on the concentration of the pulverized coal, Laser based on the degree of ignition Fuel ratio measuring method and controlling the irradiation intensity of. 4. The fuel according to claim 3 , wherein the fuel is irradiated with light that crosses the flow direction toward the pulverized coal flowing in the pipe and increases in light density toward the pulverized coal in the pipe toward the tip. Ratio measurement method.

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