Analysis system, method for analysis, and program

Abstract

To reduce influence on affecting material in a sample gas.SOLUTION: An analysis system 100 includes a radiation source 55, a detection unit 57, an acquisition unit 7, and an operation unit 591. The radiation unit 55 radiates radiation on a particulate substance FP. The detection unit 57 detects radiation which has passed through the particulate substance FP. The acquisition unit 7 acquires information on an affecting material which interacts with radiation. The operation unit 591 analyzes the particulate substance FP on the basis of the result of detecting radiation that has passed through the particulate substance FP detected by the detection unit 57 and the information acquired by the acquisition unit 7.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an analyzer for analyzing particulate matter contained in a gas existing in a predetermined region, an analysis method for analyzing the particulate matter, and a program for causing a computer to execute the analysis method.

Background Art

[0002] Conventionally, an analyzer for analyzing particulate matter contained in a gas in a predetermined environmental atmosphere is known. In this analyzer, the particulate matter contained in the gas is irradiated with radiation (for example, β-rays), and based on the intensity of the radiation after passing through the particulate matter, the concentration (mass concentration) of the particulate matter contained in the gas can be measured (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above analyzer, a gas containing particulate matter is sampled, the sampled gas (referred to as a sample gas) is held by a predetermined holding member, and the particulate matter held by the holding member is irradiated with radiation. In this analyzer, the radiation may interact not only with the particulate matter but also with substances other than the particulate matter contained in the sampling gas. That is, the radiation detected after passing through the particulate matter may be affected by substances other than the particulate matter. Thus, when the detected radiation is affected by substances other than the particulate matter and the particulate matter is analyzed based on this radiation, accurate analysis of the particulate matter may not be possible.

[0005] An object of the present invention is to reduce the influence of a substance that interacts with radiation other than particulate matter contained in a gas when analyzing particulate matter contained in the gas using radiation.

Means for Solving the Problem

[0006] A plurality of aspects will be described below as means for solving the problem. These aspects can be arbitrarily combined as necessary. An analysis system according to one aspect of the present invention is an analysis system for analyzing particulate matter contained in a sample gas. The analysis system includes a radiation source, a detector, an acquisition unit, and a calculation unit. The radiation source irradiates the particulate matter with radiation. The detector detects the radiation that has passed through the particulate matter. The acquisition unit acquires information regarding an influencing substance that interacts with the radiation. The calculation unit analyzes the particulate matter based on the detection result of the radiation that has passed through the particulate matter detected by the detector and the information acquired by the acquisition unit.

[0007] In the above analysis system, the particulate matter is irradiated with radiation, and the particulate matter is analyzed using the detection result of the radiation that has passed through the particulate matter. In this case, in the above analysis system, information regarding an influencing substance that interacts with the radiation is acquired, and the particulate matter is analyzed in consideration of not only the detection result of the radiation that has passed through the particulate matter but also the information regarding the influencing substance contained in the sample gas. Thereby, the influence of the influencing substance on the analysis result of the particulate matter using the detection result of the radiation that has passed through the particulate matter can be reduced. As a result, a more accurate analysis result of the particulate matter can be obtained.

[0008] In the above analysis system, the calculation unit may correct the detection result of the radiation that has passed through the particulate matter detected by the detector based on the above information to calculate a corrected detection result, and analyze the particulate matter based on the corrected detection result. Thereby, an analysis result of the particulate matter with less influence of the influencing substance can be obtained using the detection result (corrected detection result) in which the influence of the influencing substance on the detection result of the radiation that has passed through the particulate matter is reduced.

[0009] In the above analysis system, the calculation unit may calculate a corrected detection result by applying a predetermined function related to a parameter depending on the above information to the detection result of the radiation that has passed through the particulate matter detected by the detector. Thereby, an accurate corrected detection result can be calculated by performing a mathematical operation on the detection result of the radiation that has passed through the particulate matter.

[0010] In the above analysis system, the parameter depending on the above information may be the absorption coefficient of the radiation. Thereby, a more accurate corrected detection result can be calculated.

[0011] In the above analysis system, the calculation unit may analyze the particulate matter based on the detection result of the radiation that has passed through the particulate matter detected by the detector to obtain an uncorrected analysis result, and correct the uncorrected analysis result based on the above information. Thereby, an analysis result of the particulate matter with the influence of the interfering substance reduced can be obtained.

[0012] In the above analysis system, the interfering substance may be at least one of carbon dioxide, water, carbon monoxide, sulfur oxides, and nitrogen oxides. Thereby, in a scenario where these substances are contained in the sample gas, an analysis result of the particulate matter with the influence of the interfering substance reduced can be obtained.

[0013] An analysis method according to another aspect of the present invention is an analysis method for analyzing particulate matter contained in a sample gas. The analysis method includes the following steps. (a) Irradiating the particulate matter with radiation. (b) Detecting the radiation that has passed through the particulate matter. (c) Obtaining information about an interfering substance that interacts with the radiation. (d) Analyzing the particulate matter based on the detection result of the radiation that has passed through the particulate matter and the above information.

[0014] In the above analysis method, radiation is irradiated onto particulate matter, and the particulate matter is analyzed using the detection result of the radiation that has passed through the particulate matter. In this case, in the above analysis method, information regarding an interfering substance that interacts with the radiation is acquired, and the particulate matter is analyzed in consideration of not only the detection result of the radiation that has passed through the particulate matter but also the information regarding the interfering substance. Thereby, the influence of the interfering substance on the analysis result of the particulate matter using the detection result of the radiation that has passed through the particulate matter can be reduced. As a result, a more accurate analysis result of the particulate matter can be obtained.

[0015] A program according to still another aspect of the present invention is a program that causes a computer to execute the above analysis method.

Advantages of the Invention

[0016] The influence of an interfering substance that interacts with radiation other than the particulate matter on the analysis result of the particulate matter using the radiation that has passed through the particulate matter can be reduced. As a result, a more accurate analysis result of the particulate matter can be obtained.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0018] 1. First Embodiment (1) Outline of the Analysis System The analysis system 100 will be described below. The analysis system 100 is a system for analyzing particulate matter FP contained in gases (e.g., exhaust gas) generated in various processes (e.g., cement manufacturing process, combustion process in an ironmaking plant (blast furnace), combustion process in thermal power generation, combustion process in an incinerator, coal combustion process, heavy oil combustion process, paper manufacturing process, glass manufacturing process, refining process, etc.). The particulate matter FP that can be a measurement target is, for example, particulate substances such as unburned components in ash and fly ash.

[0019] Moreover, it is not limited to the particulate matter FP generated in various processes. For example, dust generated from various transportation devices (automobiles, ships, etc.) (dust from brakes, tires, internal combustion engines, steam engines, exhaust gas purification devices, and motors) can be the particulate matter FP that is the measurement target of the analysis system 100. Furthermore, dust generated by natural disasters such as volcanic eruptions (e.g., volcanic ash), dust generated in mining development, etc. can also be the particulate matter FP that is the measurement target.

[0020] The gases generated in the above various processes contain not only particulate matter FP but also, for example, carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NO x ), sulfur oxides (SO x ), moisture (H2O), etc. For example, the gases generated in various combustion processes contain 10 - 25 vol% (volume %) of carbon dioxide and other substances on the order of 100 - several thousand ppm. Also, the gases generated in the cement manufacturing process contain approximately 100 vol% of carbon dioxide and other substances on the order of several thousand ppm.

[0021] In the analysis system 100, the above gas is sampled, and the particulate matter FP contained in the gas is retained on the retaining member by passing the gas through the retaining member. The particulate matter FP retained on the retaining member is irradiated, and the particulate matter FP is analyzed using the radiation (for example, β-rays) that has passed through the particulate matter. In the analysis of the particulate matter FP using radiation, substances other than the particulate matter FP contained in the sampled gas at a high concentration (carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NO x ), sulfur oxides (SO x ), moisture (H2O), etc.) also interact with the radiation. Therefore, the radiation output from the radiation source 55 is also affected by substances other than the particulate matter FP before being detected by the detector 57.

[0022] For this reason, in the analysis system 100, in the analysis of the particulate matter FP using the radiation that has passed through the particulate matter FP, the influence of the above substances other than the particulate matter FP is taken into account. In addition, a substance other than the particulate matter FP contained in the sampled gas that interacts with the radiation and can affect the analysis result of the particulate matter FP is called an influencing substance. Influencing substances are, for example, at least one of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NO x ), sulfur oxides (SO x ), moisture (H2O), etc. That is, the influencing substance may be a mixture composed of a plurality of the above substances.

[0023] As described above, in various processes, the content of carbon dioxide (CO2) is particularly high. Therefore, in the analysis of the particulate matter FP, it is particularly preferable to consider the influence of carbon dioxide.

[0024] (2) Configuration of the analysis system Hereinafter, the configuration of the analysis system 100 will be described with reference to FIG. 1. FIG. 1 is a diagram showing the configuration of the analysis system. The analysis system 100 shown in FIG. 1 uses the gas generated in various processes as the gas to be measured (hereinafter referred to as the sample gas SG), and analyzes the particulate matter FP contained in the exhaust gas. The analysis system 100 includes a sampling probe 1, a diluter 3, an analyzer 5, and an acquisition unit 7.

[0025] The sampling probe 1 is fixed at a predetermined position on the side wall of the flow path FL (for example, a flue) through which the sample gas SG flows, and samples the sample gas SG from the flow path FL. The sampling probe 1 samples the sample gas SG at a flow rate determined by, for example, the amount of gas suctioned by the suction device P1 connected via the diluter 3 and the analyzer 5 from the flow path FL. The sample gas SG sampled by the sampling probe 1 is introduced into the diluter 3 through the first gas line L1.

[0026] The diluter 3 dilutes the sample gas SG by mixing the sample gas SG introduced from the first gas line L1 and the dilution gas AR supplied from the outside. The gas generated by diluting the sample gas SG with the dilution gas AR is called the diluted sample gas DG. The dilution gas AR is, for example, air. The diluted sample gas DG generated by the diluter 3 is introduced into the analyzer 5 through the second gas line L2.

[0027] The sample gas SG flowing through the flow path FL may contain a high concentration of particulate matter FP. In this way, by diluting the sample gas SG with the diluter 3 to generate the diluted sample gas DG and introducing the diluted sample gas DG into the analyzer 5, the gas (diluted sample gas DG) with a reduced concentration of particulate matter FP can be introduced into the analyzer 5. As a result, contamination of the analyzer 5 can be prevented. For example, the contamination of the nozzle 531 (such as the internal gas flow path 531a and the outlet opening 531b) described later, and / or the possibility of clogging of the holding member 51 can be reduced.

[0028] The analysis device 5 is a device that analyzes particulate matter FP contained in the diluted sample gas DG introduced through the second gas line L2. The analysis device 5 passes the diluted sample gas DG through a holding member to hold the particulate matter FP contained in the diluted sample gas DG on the holding member, irradiates the particulate matter FP held on the holding member, and analyzes the particulate matter FP using the radiation that has passed through the particulate matter FP.

[0029] The acquisition unit 7 is connected to the first gas line L1. The acquisition unit 7 acquires information regarding the influencing substances contained in the sample gas SG flowing through the first gas line L1. The information acquired by the acquisition unit 7 is output to the analysis device 5 and used for the analysis of the particulate matter FP. The information regarding the influencing substances contained in the sample gas SG may be any information regarding the influencing substances. The information includes, for example, at least one of the type of the influencing substance (e.g., information regarding the substance name, chemical formula, etc.), the characteristics of the influencing substance, the characteristic values of the influencing substance, and the content (e.g., concentration) of the influencing substance in the sample gas SG. The acquisition unit 7 is, for example, a sensor, a gas analysis device, etc. that acquires the concentration of the influencing substance contained in the sample gas SG as the above information.

[0030] Note that the acquisition unit 7 may be provided on the side wall of the flow path FL and acquire information regarding the influencing substances contained in the sample gas SG flowing through the flow path FL. In addition, the acquisition unit 7 that particularly acquires the water content (i.e., humidity) may be provided inside the analysis device 5.

[0031] Further, the analysis system 100 may include a classifier that classifies the particulate matter FP contained in the sample gas SG or the diluted sample gas DG. The classifier is provided, for example, in the first gas line L1 or the second gas line L2. Thereby, the particulate matter FP having the size after classification can be introduced into the analysis device 5.

[0032] (3) Configuration of the analysis device The configuration of the analyzer 5 will be described below with reference to FIG. 2. FIG. 2 is a diagram showing the configuration of the analyzer. The analyzer 5 includes a holding member 51, a collection device 53, a radiation source 55, a detector 57, and an analysis unit 59.

[0033] The holding member 51 collects and holds particulate matter FP contained in the diluted sample gas DG flowing through the collection device 53. Specifically, the holding member 51 is formed by laminating a collection layer made of a porous fluororesin-based material having pores capable of collecting particulate matter FP on a reinforcing layer formed of a non-woven fabric of a polymer material (such as polyethylene). With the above configuration, the holding member 51 can allow gas to flow in its thickness direction, and at the same time, its strength can be improved. Also, the holding member 51 can be made less likely to be charged. As the holding member 51, for example, a single-layer glass filter or other filters such as a single-layer filter of a fluororesin-based material can also be used.

[0034] The analyzer 5 includes a take-up reel 52a and a feed-out reel 52b. For example, one end in the length direction of the holding member 51 is connected to the take-up reel 52a. The other end in the length direction of the holding member 51 is connected to the feed-out reel 52b. The take-up reel 52a is rotatable in a predetermined direction by, for example, a motor or the like. With this configuration, by rotating the take-up reel 52a, the holding member 51 is fed out from the feed-out reel 52b and wound around the take-up reel 52a. That is, the holding member 51 can move in the length direction of the holding member 51 (the direction indicated by the thick arrow in FIG. 2) by the rotation of the take-up reel 52a and the feed-out reel 52b.

[0035] Note that the mechanism for moving the holding member 51 is not limited to the above mechanism. For example, pins may be provided in the length direction of the holding member 51, and the moving direction of the holding member 51 may be changed before and after passing through the pins. Also, a tension controller for adjusting the tension of the holding member 51 may be provided. The surface of the holding member 51 on the collection layer side where the particulate matter FP is collected is referred to as the collection surface 51a.

[0036] The collection device 53 causes the particulate matter FP contained in the diluted sample gas DG to be collected on the holding member 51. The collection device 53 has a nozzle 531. The nozzle 531 is provided at a position facing the collection surface 51a of the holding member 51. The nozzle 531 passes the diluted sample gas DG through the collection surface 51a of the holding member 51 to collect the particulate matter FP contained in the diluted sample gas DG on the collection surface 51a. The nozzle 531 has a main body made of a metal such as aluminum.

[0037] The nozzle 531 has a gas flow path 531a. The gas flow path 531a is a flow path formed inside the nozzle 531 and extending in the longitudinal direction of the nozzle 531 (the normal direction DN of the holding member 51). The normal direction DN is not limited to the direction in which the angle formed with the collection surface 51a of the holding member 51 is 90°, and may be slightly deviated from 90° with respect to the collection surface 51a of the holding member 51. For example, the normal direction DN can be defined as the direction in which the angle formed with the collection surface 51a of the holding member 51 is 80° - 100°.

[0038] The end of the gas flow path 531a on the side opposite to the arrangement side of the holding member 51 is connected to the second gas line L2. The diluted sample gas DG is introduced into the gas flow path 531a from this end of the gas flow path 531a. On the other hand, the end of the gas flow path 531a on the arrangement side of the holding member 51 is connected to the outlet opening 531b. The outlet opening 531b is the outlet of the diluted sample gas DG introduced into the gas flow path 531a. The outlet opening 531b is an opening formed at a position facing the collection surface 51a of the holding member 51.

[0039] The gas flow path 531a may extend in the gravitational direction inside the nozzle 531. Thereby, the particulate matter FP does not accumulate in the gas flow path 531a, and more particulate matter FP can be collected on the collection surface 51a of the holding member 51, so that the analysis accuracy of the particulate matter FP can be improved.

[0040] The nozzle 531 has a source installation space 531c where the radiation source 55 is provided. The source installation space 531c is a space formed to extend in a direction inclined with respect to the normal direction DN of the holding member 51 at a position deviated from the gas flow path 531a inside the nozzle 531. The source installation space 531c is connected to the gas flow path 531a.

[0041] By providing the radiation source 55 in the source installation space 531c, the radiation source 55 can be arranged inclined with respect to the normal direction DN of the holding member 51. As a result, it is possible to prevent the radiation source 55 from obstructing the flow of the sample gas SG in the gas flow path 531a, and the particulate matter FP can be uniformly collected on the collection surface 51a of the holding member 51 without unevenness. Further, by providing the source installation space 531c inside the nozzle 531, the radiation source 55 can be installed inside the nozzle 531, so that radiation can be output from a position close to the collection surface 51a of the holding member 51. As a result, radiation with a large intensity and little attenuation can be irradiated onto the collection surface 51a (particulate matter FP).

[0042] The inclination angle of the source installation space 531c with respect to the collection surface 51a of the holding member 51 is preferably set to 20° to 70°, more preferably set to 25° to 65°, and even more preferably set to 30° to 60°. For example, the above inclination angle can be 60°. By setting the inclination angle of the source installation space 531c within the above range, while avoiding the overlap of the radiation source 55 with the gas flow path 531a, most of the radiation from the radiation source 55 is irradiated onto the wall surface of the gas flow path 531a, and it is possible to prevent the particulate matter FP collected on the collection surface 51a from being insufficiently irradiated with radiation.

[0043] As described above, the linear source installation space 531c is connected to the gas flow path 531a. With this configuration, the diluted sample gas DG flowing through the gas flow path 531a and the radiation output from the radiation source 55 pass through the common gas flow path 531a and are ejected from the common outlet opening 531b toward the holding member 51. That is, the diluted sample gas DG flows through the propagation path of the radiation output from the radiation source 55, and there is a possibility that the influencing substances contained in this diluted sample gas DG interact with the radiation.

[0044] The collection device 53 has a suction portion 533. The suction portion 533 is provided so as to face the nozzle 531 with the holding member 51 interposed therebetween, and sucks the diluted sample gas DG after passing through the holding member 51. Specifically, the suction portion 533 is disposed at a position facing the nozzle 531 directly below the surface on the reinforcing layer side of the holding member 51. An opening 533a is formed in the suction portion 533. This opening 533a is connected to a third gas line L3 connected to the above-described suction device P1. In this case, the suction force generated at the opening 533a due to the suction of the suction device P1 reaches the outlet opening 531b and the gas flow path 531a connected thereto. As a result, the diluted sample gas DG is sucked into the gas flow path 531a and discharged from the outlet opening 531b. The diluted sample gas DG discharged from the outlet opening 531b passes through the holding member 51, and particulate matter FP is collected and held on the collection surface 51a of the holding member 51 during that time. The gas (the gas from which the particulate matter FP has been removed from the diluted sample gas DG) after passing through the holding member 51 is sucked into the opening 533a of the suction portion 533. The gas sucked into the opening 533a is discharged by the suction device P1.

[0045] In addition, other members such as a shutter may be provided in the nozzle 531 to block the radiation irradiated from the radiation source 55 so that it does not leak to the outside between the suction portion 533 and the nozzle 531.

[0046] The radiation source 55 is provided inside the nozzle 531 at a position inclined with respect to the normal direction DN of the collection surface 51a of the holding member 51. Specifically, the radiation source 55 is disposed in the source installation space 531c of the nozzle 531. The radiation source 55 outputs radiation that irradiates the particulate matter FP collected by the holding member 51. The radiation source 55 is, for example, a beta-ray source that generates beta rays such as carbon 14 ( 14 C), strontium 90 ( 90 Sr), promethium 147 ( 147 Pm) as radiation. These beta-ray sources emit beta rays of a single energy and emit little radiation other than beta rays (for example, gamma rays). Therefore, by using these as beta-ray sources, the generation of unnecessary radiation other than beta rays can be suppressed.

[0047] By using the radiation source 55 as a beta-ray source and irradiating the particulate matter FP collected on the collection surface 51a with beta rays, for example, the mass concentration of the particulate matter FP can be measured based on the intensity of the beta rays that have passed through the particulate matter FP. The "mass concentration of the particulate matter FP" is defined as the mass of the particulate matter contained in the total volume of the collected gas expressed as a value per unit volume of the collected gas. For example, μg / m 3 is used as the unit. Also, by irradiating the particulate matter FP with beta rays, elemental analysis of the particulate matter FP can be performed based on the fluorescent X-rays generated from the particulate matter FP.

[0048] The detector 57 is disposed on the side opposite to the collection surface 51a of the holding member 51 so as to face the outlet opening 531b, and detects the radiation output from the radiation source 55 and passing through the particulate matter FP (and the holding member 51). The detector 57 is disposed such that the radiation detection surface is perpendicular to the normal direction DN of the collection surface 51a of the holding member 51. Note that being perpendicular to the normal direction DN is not limited to the case where the angle formed with the normal direction DN is 90° (that is, parallel to the surface of the holding member 51), and may mean that the angle formed with the normal direction DN is slightly deviated from 90°. For example, being perpendicular to the normal direction DN may mean that the angle formed with the normal direction DN is 80° to 100°.

[0049] By arranging the detection surface of the detector 57 to be perpendicular to the normal direction DN of the collection surface 51a, the distance between the holding member 51 and the detection surface of the detector 57 can be shortened. As a result, the shape of the radiation irradiation region on the detection surface and the shape of the radiation irradiation region on the collection surface 51a of the holding member 51 can be made to coincide. Consequently, the entire radiation that has passed through the particulate matter FP can be detected, and the particulate matter FP can be analyzed more accurately. Also, the detection surface of the detector 57 can be brought as close as possible to the holding member 51. As a result, attenuation of radiation by substances other than the particulate matter FP can be suppressed, and the particulate matter FP can be analyzed more accurately.

[0050] When the radiation source 55 is a β-ray source, the detector 57 has, for example, a scintillator (e.g., a plastic scintillator made of polyvinyltoluene) that generates light when β-rays are incident, and a sensor (e.g., SiPM (Silicon Photomultiplier), photomultiplier tube, silicon semiconductor detector, etc.) that detects the light generated by the scintillator. The detector 57 outputs the number of detected radiations (i.e., the intensity of the detected radiation) as a "count value".

[0051] The analysis unit 59 is a computer system having a storage device such as a CPU, RAM, ROM, HDD, SSD, various interfaces, a display, etc. The analysis unit 59 executes control of each component of the analyzer 5 and various information processes related to the analyzer 5. The analysis unit 59 has an arithmetic unit 591.

[0052] The arithmetic unit 591 is composed of the CPU, storage device, and various interfaces of the analysis unit 59, and executes control of each component of the analyzer 5 and various information processes related to the analyzer 5. The arithmetic unit 591 realizes the control of each component of the analyzer 5 and various information processes related to the analyzer 5 by software that is stored in the storage device of the computer system constituting the analysis unit 59 and can be executed by the analysis unit 59. The arithmetic unit 591 may also realize part of the above control and information processing in a hardware manner.

[0053] The analysis unit 59 may include a display unit 593. The display unit 593 is a display of the analysis unit 59, and displays various information regarding the analyzer 5 and the analysis results of the particulate matter FP (for example, information regarding mass concentration, information regarding elements). The display unit 593 is, for example, a display such as a liquid crystal display or an organic EL display.

[0054] In the case where the analysis unit 59 does not include the display unit 593, for example, the analysis results and the like may be stored in the storage device of the analysis unit 59. Further, the analysis results and the like stored in the storage device may be transmitted to a terminal or the like connected to the analysis unit 59. Furthermore, the analysis results and the like may be displayed on the display unit of a terminal or the like connected to the analysis unit 59.

[0055] The analyzer 5 may further include a temperature measuring device that measures the temperature at a predetermined location of the analyzer 5, a pressure measuring device that measures the pressure at a predetermined location of the analyzer 5, and the like.

[0056] (4) Operation of the analysis system Hereinafter, with reference to FIG. 3, the analysis operation of the particulate matter FP using the analysis system 100 will be described. FIG. 3 is a flowchart showing a method for analyzing particulate matter by the analysis system. First, the particulate matter FP contained in the sample gas SG flowing through the flow path FL is sampled (step S1). Specifically, the suction device P1 is operated to generate a gas suction force at the opening 533a of the suction unit 533 and the gas flow path 531a of the nozzle 531 facing the opening 533a. This suction force also acts on the first gas line L1 to the third gas line L3, and the sample gas SG flowing through the flow path FL is sampled by the sampling probe 1.

[0057] The sampled sample gas SG flows into the diluter 3 through the first gas line L1. The sample gas SG that has flowed into the diluter 3 is diluted by the dilution gas AR that has flowed into the diluter 3. In this way, by diluting the sample gas SG with the dilution gas AR in the diluter 3, a diluted sample gas DG is generated. After generating the diluted sample gas DG, due to the suction force of the suction device P1, the diluted sample gas DG in the diluter 3 flows into the gas flow path 531a of the nozzle 531 of the analyzer 5.

[0058] The diluted sample gas DG that has flowed into the gas flow path 531a advances in the normal direction DN of the holding member 51 in the gas flow path 531a, exits from the outlet opening 531b, and passes through the collection surface 51a of the holding member 51. While the diluted sample gas DG is passing through the holding member 51, the particulate matter FP contained in the diluted sample gas DG is collected and held on the collection surface 51a of the holding member 51.

[0059] While the particulate matter FP is being held by the holding member 51 as described above, the radiation output from the radiation source 55 is irradiated onto the particulate matter FP held by the holding member 51 (step S2). In this way, while the particulate matter FP is being held by the holding member 51, that is, in a state where the diluted sample gas DG is flowing through the gas flow path 531a, the radiation output from the radiation source 55 is irradiated onto the particulate matter FP held by the holding member 51. In other words, the diluted sample gas DG exists in the propagation path of the radiation output from the radiation source 55.

[0060] As described above, the diluted sample gas DG may contain substances that interact (e.g., absorb) with radiation. If such substances are contained in the diluted sample gas DG, before the radiation output from the radiation source 55 reaches the detector 57, the radiation also interacts (e.g., is absorbed by the substances) with the substances in the diluted sample gas DG, and the detection result of the radiation detected by the detector 57 may be different from the case where the radiation interacts only with the particulate matter FP (e.g., is absorbed only by the particulate matter FP). That is, the detection result of the radiation passing through the particulate matter FP detected by the detector 57 may be affected by the substances contained in the diluted sample gas DG. Therefore, when the analyzer 5 analyzes the particulate matter FP using the radiation detected by the detector 57, the influence of the substances contained in the diluted sample gas DG is also taken into account.

[0061] As described above, the sample gas SG generated in various processes contains a large amount of carbon dioxide (CO2) in particular. Therefore, when analyzing the particulate matter FP, it is particularly preferable to consider the influence of carbon dioxide.

[0062] While the particulate matter FP is held by the holding member 51, the arithmetic unit 591 of the analysis unit 59 acquires, from the detector 57, the detection result of the radiation passing through the particulate matter FP at predetermined time intervals (step S3). For example, the arithmetic unit 591 acquires, every second, the count value of the radiation detected by the detector 57 in one second.

[0063] In addition, when the arithmetic unit 591 acquires the detection result of the radiation, it acquires information regarding the substances contained in the sample gas SG from the acquisition unit 7. The arithmetic unit 591 corrects the information regarding the substances acquired from the acquisition unit 7 based on the dilution ratio of the sample gas SG in the diluter 3, and acquires information regarding the substances contained in the diluted sample gas DG (step S4).

[0064] Next, the arithmetic unit 591 analyzes the particulate matter FP held by the holding member 51 based on the radiation detection result acquired in step S3 and the information on the influencing substance acquired in step S4 (step S5). When the radiation source 55 is a β-ray source, specifically, the arithmetic unit 591 calculates the mass concentration of the particulate matter FP contained in the sample gas SG based on the radiation detection result and the information on the influencing substance acquired in step S4.

[0065] The analysis of the particulate matter FP is executed, for example, according to the flowchart shown in FIG. 4. FIG. 4 is a flowchart showing details of the method for analyzing particulate matter in the first embodiment. First, the arithmetic unit 591 corrects the radiation detection result detected by the detector 57 based on the information on the influencing substance to calculate a corrected detection result (step S51). Specifically, the arithmetic unit 591 calculates the corrected detection result by applying a predetermined function regarding a parameter depending on the information on the influencing substance to the radiation detection result.

[0066] For example, when the radiation detection result is the count value of the radiation detected by the detector 57 per second, the corrected detection result can be calculated using the formula shown in Equation 1 below.

Equation

[0067] In Equation 1 above, I is the count value of the radiation detected by the detector 57. I s is the corrected detection result. μ is the absorption coefficient, ρ s is the standard density, T s is the standard temperature, P s is the standard pressure. ρ s (standard density), T s (standard temperature), P s (standard pressure) can be predetermined constants. Also, S is the collection spot diameter, V U is the volume on the upstream side of the location where the diluted sample gas DG flows, P U is the pressure on the upstream side of the location where the diluted sample gas DG flows, V Lis the volume on the downstream side where the diluted sample gas DG flows, P L is the pressure on the downstream side where the diluted sample gas DG flows, T F is the temperature of the diluted sample gas DG. S (collection spot diameter), V U (upstream volume), P U (upstream pressure), V L (downstream volume), P L (downstream pressure), T F (temperature of the diluted sample gas DG) can be a constant determined according to the dimensions of the analyzer 5 and the like.

[0068] Among the parameters included in Equation 1, the absorption coefficient (μ) is a parameter that depends on information regarding the influencing substance contained in the diluted sample gas DG (for example, the content (concentration) of the influencing substance in the diluted sample gas DG). Therefore, when calculating the corrected detection result (I in Equation 1 s ), the arithmetic unit 591 uses, as the absorption coefficient (μ), a value corresponding to the information regarding the influencing substance acquired in step S4. The absorption coefficient corresponding to the acquired information regarding the influencing substance can be determined based on, for example, the measurement results measured when flowing a diluted sample gas DG containing an influencing substance with a known concentration, and / or based on the execution results of simulations and the like.

[0069] After calculating the corrected detection result, the arithmetic unit 591 analyzes the particulate matter FP based on the corrected detection result (step S52). Specifically, the arithmetic unit 591 calculates the mass concentration of the particulate matter FP from the corrected detection result (corrected count value). The arithmetic unit 591 calculates, for example, the retention amount of the particulate matter FP after a predetermined time (assumed to be t seconds) has elapsed since the start of the analysis of the particulate matter FP using the following Equation 2, and divides this retention amount by the total flow rate of the diluted sample gas DG up to t seconds to calculate the mass concentration of the particulate matter FP in the diluted sample gas DG. Further, the mass concentration of the particulate matter FP in the sample gas SG can be calculated by correcting the mass concentration of the particulate matter FP in the diluted sample gas DG based on the dilution ratio of the diluted sample gas DG.

Equation

[0070] In the above formula (2), M is the amount of particulate matter held by the holding member 51 after t seconds have elapsed since the start of the analysis. I s (0) is the corrected detection result immediately after the start of the analysis, I s (t) is the corrected detection result after t seconds have elapsed since the start of the analysis. μ is the absorption coefficient, k is the scale coefficient, and S is the collection spot diameter. The absorption coefficient (μ) in formula (2) is a constant that does not depend on (i.e., is not affected by) information regarding the influencing substance. Also, k (scale coefficient) and S (collection spot diameter) can also be constants.

[0071] In addition, the arithmetic unit 591 calculates the above-described holding amount at predetermined time intervals (e.g., every 1 second) since the start of the analysis, calculates the increase amount of the holding amount per unit time (e.g., per 1 second) from this holding amount, and calculates the final holding amount after a long time (e.g., 1 hour) has elapsed since the start of the analysis by cumulatively adding the increase amounts of the holding amount. Then, the arithmetic unit 591 may calculate the final mass concentration by dividing this final holding amount by the total flow rate of the diluted sample gas DG.

[0072] In the analysis system 100, information regarding an influencing substance that interacts with radiation is acquired, and the particulate matter FP is analyzed in consideration of not only the radiation that has passed through the particulate matter FP but also the information regarding the influencing substance. Thereby, the influence of the influencing substance on the analysis result of the particulate matter using the detection result of the radiation that has passed through the particulate matter FP can be reduced. As a result, a more accurate analysis result of the particulate matter can be obtained.

[0073] In the first embodiment, the detection result of the radiation that has passed through the particulate matter FP is corrected based on the information regarding the influencing substance to calculate a corrected detection result. Specifically, the corrected detection result is calculated using formula (1), and the particulate matter is analyzed based on the corrected detection result. Thereby, an analysis result of the particulate matter with less influence of the influencing substance can be obtained using the detection result (corrected detection result) in which the influence of the influencing substance on the detection result of the radiation that has passed through the particulate matter FP is reduced.

[0074] As described above, the sample gas SG generated in various processes contains a large amount of carbon dioxide (CO2) in particular. Therefore, it is preferable to correct the detection result of the radiation that has passed through the particulate matter FP based on information regarding carbon dioxide contained in the diluted sample gas DG (for example, the concentration of carbon dioxide in the diluted sample gas DG), and calculate the corrected detection result. Thereby, the influence of carbon dioxide that has a great influence on the analysis result of the particulate matter FP is reduced, and a more accurate analysis result of the particulate matter FP can be obtained.

[0075] 2. Second Embodiment In the first embodiment described above, the detection result of the radiation that has passed through the particulate matter FP detected by the detector 57 is corrected using the above equation (1) and the like to obtain a corrected detection result with the influence of the interfering substance reduced, and the particulate matter FP is analyzed using this corrected detection result. However, the method for reducing the influence of the interfering substance is not limited to this.

[0076] In the analysis system according to the second embodiment, the particulate matter FP is analyzed using the detection result of the radiation that has passed through the particulate matter FP detected by the detector 57, and the analysis result is corrected based on information regarding the interfering substance, thereby obtaining an analysis result with the influence of the interfering substance reduced.

[0077] The analysis system according to the second embodiment has the same configuration and functions as the analysis system 100 according to the first embodiment, except that the content of the process in step S5 of the analysis method of the particulate matter FP described in the first embodiment is different. Therefore, hereinafter, only the detailed content of the process in step S5 of the analysis method of the particulate matter FP in the second embodiment will be described, and other descriptions such as the configuration of the analysis system will be omitted.

[0078] In the analysis system of the second embodiment, steps S1 to S4 of the flowchart of FIG. 3 described in the first embodiment are executed. After acquiring the detection result of the radiation detected by the detector 57 and the information on the influencing substance, step S5 is executed to analyze the particulate matter FP. In the second embodiment, the analysis of the particulate matter FP is executed according to the flowchart shown in FIG. 5. FIG. 5 is a flowchart showing details of the method for analyzing particulate matter in the second embodiment.

[0079] First, the arithmetic unit 591 analyzes the particulate matter FP based on the detection result of the radiation detected by the detector 57 to obtain a pre-correction analysis result (step S51'). Specifically, the arithmetic unit 591 calculates the analysis result (mass concentration) of the particulate matter FP from the detection result of the radiation in the same manner as described in the first embodiment using the above numbers 1 and 2. In the second embodiment, a constant independent of the influencing substance is used as the absorption coefficient (μ) of number 1.

[0080] Next, the arithmetic unit 591 corrects the pre-correction analysis result calculated in step S51' based on the information on the influencing substance (step S52'). For example, when the analysis result of the particulate matter FP is the mass concentration, the pre-correction mass concentration can be corrected as follows. First, the arithmetic unit 591 calculates the detection result (radiation count value) of the radiation obtained when the diluted sample gas DG contains the influencing substance based on the information on the influencing substance (for example, the concentration of the influencing substance, etc.), and calculates the mass concentration of the particulate matter FP corresponding to the influence of the influencing substance from this detection result.

[0081] The detection result (radiation count value) of the radiation when the influencing substance is contained can be determined based on, for example, the actual measurement results measured when flowing a diluted sample gas DG containing an influencing substance with a known concentration, and / or based on the execution results of simulations or the like.

[0082] Thereafter, the arithmetic unit 591 can calculate the mass concentration of particulate matter FP with the influence of the interfering substance reduced (analysis result) by subtracting the mass concentration of particulate matter FP corresponding to the influence of the interfering substance calculated as described above from the mass concentration before correction calculated in step S51'.

[0083] As described above, by analyzing the particulate matter FP based on the radiation that has passed through the particulate matter FP detected by the detector 57 to obtain the analysis result before correction, and correcting the analysis result before correction based on the information regarding the interfering substance, it is also possible to obtain the analysis result of the particulate matter FP with the influence of the interfering substance reduced.

[0084] As described above, the sample gas SG generated in various processes contains a large amount of carbon dioxide (CO2) in particular. Therefore, it is preferable to correct the above-described analysis result before correction based on the information regarding carbon dioxide contained in the diluted sample gas DG (for example, the concentration of carbon dioxide in the diluted sample gas DG) to obtain the final analysis result. Thereby, the influence of carbon dioxide that greatly affects the analysis result of the particulate matter FP is reduced, and a more accurate analysis result of the particulate matter FP can be obtained.

[0085] 3. Other Embodiments As described above, a plurality of embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the gist of the invention. In particular, the plurality of embodiments and modification examples described in this specification can be arbitrarily combined as necessary. (A) The processing contents and processing order of each step in the method for analyzing particulate matter FP described with reference to FIGS. 3 to 5 can be changed without departing from the gist of the invention.

[0086] In the first embodiment, the corrected detection result was calculated by applying the above formula (1) to the detection result of the radiation that passed through the particulate matter FP detected by the detector 57. However, the method for calculating the corrected detection result is not limited to this. For example, the corrected detection result can also be calculated by multiplying the detection result of the radiation by a correction coefficient that changes according to information on the influencing substance (e.g., the concentration of the influencing substance), or by dividing the detection result of the radiation by a correction coefficient that changes according to information on the influencing substance (e.g., the concentration of the influencing substance). Then, by applying formula (1) and formula (2) (using a value of the absorption coefficient (μ) that does not depend on information on the influencing substance) to this corrected detection result, an analysis result of the particulate matter FP with the influence of the influencing substance reduced can be obtained.

[0087] In the second embodiment, the particulate matter FP was analyzed based on the detection result of the radiation that passed through the particulate matter FP detected by the detector 57 to obtain a pre-correction analysis result (mass concentration), and the final analysis result of the particulate matter FP was obtained by subtracting the analysis result (mass concentration) of the particulate matter FP corresponding to the influence of the influencing substance from the pre-correction analysis result. However, it is not limited to this. For example, the analysis result with the influence of the influencing substance reduced can be calculated by multiplying the pre-correction analysis result by a correction coefficient that changes according to information on the influencing substance (e.g., the concentration of the influencing substance), or by dividing the pre-correction analysis result by a correction coefficient that changes according to information on the influencing substance (e.g., the concentration of the influencing substance).

[0088] (B) The analysis system 100 may have a function of performing other analyses on the particulate matter FP. For example, the analysis system 100 may be able to analyze the identification of elements contained in the particulate matter FP and the content of the elements based on the fluorescent X-rays generated from the particulate matter FP. In this case, the analysis system 100 may further include a radiation source that irradiates the particulate matter FP with X-rays and a detector that detects the fluorescent X-rays generated from the particulate matter FP.

[0089] Alternatively, the analysis system 100 may detect fluorescent X-rays generated by irradiating the particulate matter FP with radiation from the radiation source 55 without separately providing a source of X-rays for irradiating the particulate matter FP.

[0090] In addition, the analysis system 100 may acquire image data obtained by photographing the particulate matter FP (and its surroundings) held on the collection surface 51a of the holding member 51, and perform analysis of the particulate matter FP (for example, calculate the mass concentration of the particulate matter FP, identify the specific substance, contained elements, etc. of the particulate matter FP from the color of the particulate matter FP, etc.) based on the acquired image data.

[0091] (C) Based on the analysis results obtained by the above analysis system, the control of other devices may be performed. For example, when the particulate matter FP generated in the waste incineration facility is the analysis target, whether or not the particulate matter FP contains harmful substances may be output as the analysis result, and when this analysis result is output, a predetermined device of the waste incineration facility may be operated.

[0092] (D) In the above analysis system 100, the diluted sample gas DG is passed through the collection surface 51a of the holding member 51 by the suction of the suction unit 533. However, it is not limited to this, and the particulate matter FP may be collected on the collection surface 51a by pushing the diluted sample gas DG into the collection surface 51a (that is, spraying the diluted sample gas DG onto the collection surface 51a at a predetermined pressure). In this case, the suction unit 533 may be omitted.

[0093] (E) In the above analysis system 100, the radiation source 55 is provided in the source installation space 531c inside the nozzle 531, but it is not limited to this. The radiation source 55 may be provided outside the nozzle 531 at a position inclined with respect to the normal direction DN of the collection surface 51a.

[0094] (F) The radiation source 55 is not limited to a beta-ray source, and other radiation sources such as a gamma-ray source and an X-ray source can be used according to the analysis items of the particulate matter FP and the like.

[0095] (G) Even for the analyzer 5 in which the collection device 53 does not have the nozzle 531 and / or the suction unit 533, the method for analyzing the particulate matter FP described above can be applied.

[0096] (H) For example, when it is not necessary to dilute the sample gas SG, the diluter 3 may be omitted in the analysis system 100. In this case, the sample gas SG is introduced into the analyzer 5.

[0097] (I) In the analyzers 5 of the first and second embodiments, the radiation source 55 was arranged in the source installation space 531c inclined with respect to the normal direction DN, and radiation was irradiated obliquely from the radiation source 55. However, it is not limited to this. For example, in the analyzer 5' shown in FIG. 6, the radiation source 55 may be arranged in the gas flow path 531a' of the nozzle 531' of the collection device 53', and radiation may be irradiated from the radiation source 55 in the normal direction DN. FIG. 6 is a diagram showing another example of the configuration of the analyzer.

[0098] 4. Features of the Embodiment The above first and second embodiments can also be described as follows. (1) The analysis system (for example, the analysis system 100) is an analysis system that analyzes particulate matter (for example, particulate matter FP) contained in a sample gas (for example, sample gas SG, diluted sample gas DG). The analysis system includes a radiation source (for example, radiation source 55), a detector (for example, detector 57), an acquisition unit (for example, acquisition unit 7), and a calculation unit (for example, calculation unit 591). The radiation source irradiates the particulate matter with radiation. The detector detects the radiation that has passed through the particulate matter. The acquisition unit acquires information regarding an influencing substance that interacts with the radiation. The calculation unit analyzes the particulate matter based on the detection result of the radiation that has passed through the particulate matter detected by the detector and the information acquired by the acquisition unit.

[0099] In the above analysis system, radiation is irradiated onto particulate matter, and the particulate matter is analyzed using the detection result of the radiation that has passed through the particulate matter. In this case, in the above analysis system, information regarding an interfering substance that interacts with the radiation is acquired, and the particulate matter is analyzed in consideration of not only the detection result of the radiation that has passed through the particulate matter but also information regarding the interfering substance contained in the sample gas. Thereby, the influence of the interfering substance on the analysis result of the particulate matter using the detection result of the radiation that has passed through the particulate matter can be reduced. As a result, a more accurate analysis result of the particulate matter can be obtained.

[0100] (2) In the analysis system of (1) above, the arithmetic unit may correct the detection result of the radiation that has passed through the particulate matter detected by the detector based on the above information to calculate a corrected detection result, and analyze the particulate matter based on the corrected detection result. Thereby, an analysis result of the particulate matter with less influence of the interfering substance can be obtained using the detection result (corrected detection result) in which the influence of the interfering substance on the detection result of the radiation that has passed through the particulate matter is reduced.

[0101] (3) In the analysis system of (2) above, the arithmetic unit may calculate a corrected detection result by applying a predetermined function regarding a parameter that depends on the above information to the detection result of the radiation that has passed through the particulate matter detected by the detector. Thereby, an accurate corrected detection result can be calculated by a mathematical operation on the detection result of the radiation that has passed through the particulate matter detected by the detector.

[0102] (4) In the analysis system of (3) above, the parameter that depends on the above information may be an absorption coefficient of the radiation. Thereby, a more accurate corrected detection result can be calculated.

[0103] (5) In the analysis system of (1) above, the arithmetic unit may analyze the particulate matter based on the detection result of the radiation that has passed through the particulate matter detected by the detector to obtain an analysis result before correction, and correct the analysis result before correction based on the above information. Thereby, an analysis result of the particulate matter with reduced influence of the interfering substance can be obtained.

[0104] (6) In any of the analysis systems of (1) to (5) above, the influencing substance may be at least one of carbon dioxide, water, carbon monoxide, sulfur oxides, and nitrogen oxides. Thereby, in a situation where these substances are contained in the sample gas, an analysis result of particulate matter with the influence of the influencing substance reduced can be obtained.

[0105] (7) An analysis method according to another aspect of the present invention is an analysis method for analyzing particulate matter contained in a sample gas. The analysis method includes the following steps. Note that the descriptions such as (a), (b), ··· below in this specification do not limit the order of each step. (a) A step of irradiating the particulate matter with radiation. (b) A step of detecting the radiation that has passed through the particulate matter. (c) A step of acquiring information regarding an influencing substance that interacts with the radiation. (d) A step of analyzing the particulate matter based on the detection result of the radiation that has passed through the particulate matter and the above information.

[0106] In the above analysis method, the particulate matter is irradiated with radiation, and the particulate matter is analyzed using the detection result of the radiation that has passed through the particulate matter. In this case, in the above analysis method, information regarding an influencing substance that interacts with the radiation is acquired, and the particulate matter is analyzed in consideration of not only the detection result of the radiation that has passed through the particulate matter but also the information regarding the influencing substance. Thereby, the influence of the influencing substance on the analysis result of the particulate matter using the detection result of the radiation that has passed through the particulate matter can be reduced. As a result, a more accurate analysis result of the particulate matter can be obtained.

Industrial Applicability

[0107] The present invention can be widely applied when analyzing particulate matter contained in a gas existing in a predetermined region.

Explanation of Signs

[0108] 100: Analysis system 1: Sampling probe 3: Diluter 5, 5’: Analyzer 51: Holding member 51a: Collection surface 52a: Take-up reel 52b: Delivery reel 53, 53’: Collection device 531, 531’: Nozzle 531a, 531a’: Gas flow path 531b: Outlet opening 531c: Line source installation space 533: Suction part 533a: Opening 55: Radiation source 57: Detector 59: Analysis part 591: Calculation part 593: Display part 7: Acquisition part FL: Flow path L1: First gas line L2: Second gas line L3: Third gas line P1: Suction device SG: Sample gas DG: Diluted sample gas FP: Particulate matter

Claims

1. An analysis system for analyzing particulate matter contained in a sample gas, comprising: a radiation source that irradiates the particulate matter with radiation; a detector that detects the radiation that has passed through the particulate matter; an acquisition unit that acquires information on an influencing substance that interacts with the radiation; an arithmetic unit that analyzes the particulate matter based on the detection result of the radiation that has passed through the particulate matter detected by the detector and the information acquired by the acquisition unit; An analysis system comprising:

2. The arithmetic unit corrects the detection result of the radiation that has passed through the particulate matter detected by the detector based on the information to calculate a corrected detection result, The analysis system according to claim 1, wherein the particulate matter is analyzed based on the corrected detection result.

3. The arithmetic unit according to claim 2, wherein the corrected detection result is calculated by applying a predetermined function regarding a parameter that depends on the information to the detection result of the radiation that has passed through the particulate matter detected by the detector.

4. The analysis system according to claim 3, wherein the parameter that depends on the information is an absorption coefficient of the radiation.

5. The arithmetic unit analyzes the particulate matter based on the detection result of the radiation that has passed through the particulate matter detected by the detector to obtain an uncorrected analysis result, and corrects the uncorrected analysis result based on the information. The analysis system according to claim 1.

6. The analysis system according to any one of claims 1 to 5, wherein the influencing substance is at least one of carbon dioxide, water, carbon monoxide, sulfur oxides, and nitrogen oxides.

7. An analysis method for analyzing particulate matter contained in a sample gas, comprising: irradiating the particulate matter with radiation; detecting the radiation that has passed through the particulate matter; acquiring information on an influencing substance that interacts with the radiation; analyzing the particulate matter based on the detection result of the radiation that has passed through the particulate matter and the information; An analysis method comprising:

8. A program for causing a computer to execute an analysis method for analyzing particulate matter contained in a sample gas, the analysis method comprising: irradiating the particulate matter with radiation; detecting the radiation that has passed through the particulate matter; acquiring information on an influencing substance that interacts with the radiation; Based on the detection result of the radiation that has passed through the particulate matter and the information, a step of analyzing the particulate matter; A program comprising the above.

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