JP2009166207A - Blasting device and its operation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blasting device and its operation method particularly suitable for decontamination work, by efficiently performing blasting work. <P>SOLUTION: A dust quantity in a clean house 44 for using the blasting device 10 is detected by particle sensors 46A-46F, and a blasting medium supply quantity by a blasting medium supply part 30 and/or a liquid supply quantity by a flow regulating valve 36, are controlled by a control part 48 based on the detected dust quantity. That is, this operation method restrains generation of dust by increasing the liquid supply quantity by largely controlling opening of the flow regulating valve 36 when the detected dust quantity becomes more than a specified value determined that the dust is generated. Thus, a blasting work environment in the clean house 44 can be automatically excellently maintained. When the dust quantity becomes largely less than the specified value, since there is risk of independently projecting liquid, the opening of the flow regulating valve 36 is controlled small, and independent projection of the liquid is prevented by reducing the liquid supply quantity. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a blasting apparatus and a method for operating the blasting apparatus, and in particular, a blasting apparatus mainly for removing a coating film on a wall surface of a nuclear power plant facility or decontaminating a ground surface from which a coating film has been removed, and It relates to the driving method.

  In recent years, regarding the decommissioning of nuclear power plant facilities, legislation has been put in place regarding dismantling standards for such decommissioning. When dismantling the reactor facilities, it is necessary to prevent the diffusion of radioactive materials. If the base material is painted, first remove the coating film containing radioactive material on its wall surface, and then decontaminate the ground surface (base material) from which the coating film has been removed to contaminate the ground surface. (Radioactive contaminants from radiation) need to be removed.

  The present applicant has proposed a blasting apparatus in Patent Document 1 for the purpose of removing a coating film containing such a radioactive substance and decontaminating the ground surface.

  The blasting apparatus of Patent Document 1 uses a blast medium in which an abrasive is fixed in a porous elastic body (sponge), projects the blast medium toward a painted wall surface, removes the coating film, and removes the ground surface. Decontamination is performed. According to this blasting apparatus, when the blasting medium collides with the coating film, the blasting medium becomes flat and the fixed abrasive directly collides with the coating film at high speed. Can be removed by grinding. In addition, since dust that normally floats in the air is taken into the porous elastic body and falls as it is, dust scattering can be prevented. Due to such advantages, there is a specific effect that the working environment is greatly improved and the blasting work can be carried out efficiently as compared with the sandblasting apparatus in which a large amount of dust drifts in the working environment.

  By the way, the dry blasting apparatus disclosed in Patent Document 1 mainly uses a blasting medium in which a hard abrasive such as alumina or zirconia is fixed to a porous elastic body. It can be carried out. However, when decontaminating the substrate, wet blasting using a liquid blasting medium containing abrasive in water, even when using a low-hardness abrasive (such as a polishing material) such as urea resin, is used. Compared with an apparatus, that is, compared with an apparatus for washing out contaminants with a liquid, it cannot be denied that the decontamination efficiency is still inferior.

FIG. 1 of Patent Document 2 shows a wet blasting apparatus that supplies abrasive material to a steam water mixing nozzle of a steam injector including a water nozzle and a steam nozzle, and grinds an oxide film of a workpiece and a metal base material. It is disclosed. In this blasting apparatus, compressed air and an abrasive are pressure-fed to a building-buried pipe of a nuclear facility to grind an oxide film and a metal base material on the inner surface of the pipe.
JP 2006-130618 A JP 2000-75095 A

  Since the wet blasting apparatus of Patent Document 2 can wash away contaminants with water, it can be said that the decontamination efficiency is higher than that of the dry blasting apparatus of Patent Document 1. However, since the wet blasting apparatus such as Patent Document 2 is an apparatus mainly based on water cleaning, secondary cleaning in which contamination containing radioactive pollutants is mixed with water is generated by water cleaning. There was a drawback in that special equipment was required for the water treatment.

  Further, in the wet blasting apparatus of Patent Document 2, if the amount of water supplied is reduced in order to suppress the generation of secondary waste, the blasting operation cannot be carried out efficiently because dust due to the abrasive material is scattered. was there.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a blasting apparatus that can efficiently perform a blasting operation and that is particularly suitable for a decontamination operation, and an operating method thereof.

  In order to achieve the above object, the blasting apparatus according to claim 1 is a tank in which a blast medium is stored and a blast medium supply port is formed at a predetermined position, and the supply port of the tank. A hose with a base end connected to the nozzle, a nozzle connected to the tip of the hose, a compressed air supply unit for supplying compressed air to the base end of the hose, and a base end of the hose. And a liquid supply unit that supplies liquid toward a supply point of the blast medium supplied from the supply port of the tank, and detects a dust amount in a blast target chamber in which the blast device is used The blast medium supply amount by the blast medium supply unit of the blasting device and / or the liquid supply amount by the liquid supply unit is detected based on the detected dust amount. It is characterized in that controlled by control unit.

  According to a fourth aspect of the present invention, there is provided a method of operating a blasting apparatus, comprising: a tank in which a blast medium is stored and a blast medium supply port is formed at a predetermined position; A hose having a base end connected to the supply port; a nozzle connected to the tip of the hose; a compressed air supply for supplying compressed air to the base end of the hose; and a base end of the hose And a liquid supply unit that supplies liquid toward the supply point of the blast medium supplied from the supply port of the tank, and the blast target in which the blast device is used The amount of dust in the room is detected by the detection means, and based on the detected amount of dust, the blast medium supply amount and / or the liquid supply by the blast medium supply unit of the blast device It is characterized in that controlled by the control unit of the liquid supply amount by.

  According to the first and fourth aspects of the invention, the blast medium and the liquid are mixed at the base end portion of the hose, and the mixed medium of the mixed blast medium and the liquid is pneumatically transported in the hose with compressed air. Projection from the nozzle at the tip of the hose toward the workpiece. Thereby, the mixed medium is projected at a high speed without being decelerated at the position of the nozzle. In addition, since the mixing area becomes longer when the blast medium and the liquid pass through the hose, the blast medium and the liquid are reliably mixed. Due to this mixing action, the liquid entangles well with the blasting medium (in the case of a blasting medium that absorbs water, the blasting medium wets), so that the liquid is not directly projected from the nozzle and the tangled liquid ( A wet blast medium) is projected from the nozzle. Thereby, generation | occurrence | production of the dust resulting from the projected blasting medium can be suppressed. Moreover, in the case of the use for the purpose of decontamination, since the contamination of the ground surface is removed like water washing by the liquid entangled with the blasting medium, decontamination can be performed efficiently. Furthermore, since the liquid is entangled with the blast medium and is not projected by the liquid alone, generation of secondary waste (water) can be suppressed.

  On the other hand, the used blasting medium dropped by blasting becomes a lump because the liquid is entangled. Thereby, it can collect | recover easily compared with water. If the recovered blasting medium contains radioactive contaminants, store it in a cask and store it in an existing radiation control area. Therefore, compared with water containing radioactive pollutants, water treatment facilities for secondary waste become unnecessary, and handling of secondary waste becomes much easier.

  In the first and fourth aspects of the invention, the amount of dust in the blast target room in which the blasting device is used is detected by a detection means such as a particle sensor. And a control part controls the liquid supply amount by a liquid supply part based on the detected dust amount. That is, when the amount of dust exceeds a specified value that is a dust generation value, the liquid supply amount is increased to suppress dust generation. Thereby, the blasting work environment can be maintained well and automatically, and the blasting work can be carried out efficiently. Further, when the amount of dust is significantly smaller than the specified value, there is a possibility that the liquid is projected alone, so the liquid supply amount is reduced to prevent the liquid from being projected alone. In this case, control may be performed so as to increase the supply amount of the blast medium, or both supply amounts may be controlled as described above.

  According to the second and fifth aspects of the present invention, a plurality of the detection means are provided substantially along a path from the projected part on which the blast medium in the blast target chamber is projected to the exhaust port of the blast target chamber. At the start of projection of the blast medium, the unit detects the dust amount by a plurality of detection means in the vicinity of the exhaust port separated from the projection target part, and acquires the average. The control unit controls the liquid supply unit to increase the liquid supply amount so that the dust amount becomes smaller than the predetermined value when the average amount of dust is larger than the predetermined value, and / or The amount of dust is suppressed by controlling the blast medium supply unit so that the supply amount of the blast medium is reduced to be smaller than the predetermined value.

  At the initial stage of projection of the blast medium, the amount of air hitting the projected portion is still small, and the amount of air reflected and flowing to the exhaust port and the amount of dust are also small. Therefore, if there are six detection means, for example, the dust amount is detected by two detection means close to the exhaust port, the average is taken, and this value is taken as the dust amount. When the amount of dust is greater than a certain value, the amount of moisture is increased and control is performed to reduce the amount of dust.

  If the dust amount is still greater than a certain value after the predetermined time has elapsed, the blast medium supply amount is further reduced. If the liquid increases due to this, the walls and floor of the blast target chamber become sticky with the liquid and the blasting medium, so the compressed air supply unit is controlled to reduce the amount of compressed air. That is, the amount of dust is reduced by sequentially or simultaneously performing the above three controls.

  According to the third and sixth aspects of the present invention, when the blast medium projection has elapsed for a predetermined time, the control unit sequentially increases the number of detection means to be operated from the downstream side to the upstream side of the path. When the amount of air is the largest, it is preferable to operate all detection means.

  As projection progresses and the amount of air and dust per hour increases, the amount of air and dust reflected from the projected part also increases, so it is proportional to the amount of air (the amount of air is converted from the nozzle pressure). Thus, the number of operation of the detection means is sequentially increased from the downstream side to the upstream side of the path. When the amount of air per hour is the largest, all detection means are activated. On the other hand, if the average value is obtained with the dust amount of all detection means when the air amount is small, the dust amount on the upstream side of the path with a small amount of dust is also used as the calculated value. Less than. Therefore, as described above, the accuracy of dust amount detection is improved by sequentially increasing the number of detection means operating in accordance with the progress of the projection time from the downstream side to the upstream side of the path.

  According to the invention described in claim 7, it is preferable to use a powdery medium as the blast medium. Projection of powdered media in a dry process is not desirable from the viewpoint of the work environment because a large amount of dust is generated by powder, but if blasting media is mixed with liquid and projected, the blasting medium becomes wet, and dust is generated. And can be easily collected.

  Even if the blast medium is powdery, if the hardness is high (for example, Mohs hardness 6 or more), hard work such as grinding of the coating film can be performed, and if the hardness is low (for example, less than Mohs hardness 6) ), Soft work such as decontamination work (contamination removal work adhering to the ground) and mirror finishing can be performed.

  According to invention of Claim 8, it is preferable to use a calcium carbonate powder as a powdery medium. For example, a powdered blasting medium suitable for protecting global environmental resources can be obtained by using a pulverized shell such as scallop as calcium carbonate powder. The calcium carbonate powder may be industrially produced, or may be fixed to a sponge piece to form a sponge blast medium.

  According to the blasting apparatus and the operating method thereof according to the present invention, the amount of dust in the blasting target chamber in which the blasting apparatus is used is detected by the detecting means, and the control unit is configured to detect the amount of liquid by the liquid supply unit based on the detected amount of dust. Since the supply amount is controlled so as not to generate dust, the blasting work environment can be maintained automatically and satisfactorily, and the blasting work can be carried out efficiently.

  Hereinafter, preferred embodiments of a blasting apparatus and an operation method thereof according to the present invention will be described in detail according to the accompanying drawings.

  A blasting apparatus 10 of the embodiment shown in FIG. 1 is a blasting apparatus used for decontamination of the ground 14 from which the coating film on the wall surface 12 of the nuclear power plant facility has been removed.

  First, a decontamination method using the blasting apparatus 10 will be described. A blast medium used in this decontamination method is a mixed medium 20 in which powdered calcium carbonate powder and a liquid are mixed, and the liquid is independent. The mixed medium 20 is in a state in which the calcium carbonate powder is not separated but is soaked into the calcium carbonate powder and the calcium carbonate powder is wet with a liquid. This mixed medium 20 is projected onto the ground surface 14 with compressed air at a high speed to decontaminate the ground surface 14. In addition, it may replace with calcium carbonate powder and may use No. 7 silica sand as a blasting medium.

  According to this blasting device 10, when the mixed medium 20 collides with the ground 14, the calcium carbonate powder collides with the liquid 14 directly with the liquid at a high speed. With this impact force, the substrate 14 is decontaminated and the substrate is adjusted, and contaminants adhering to the substrate 14 are removed by liquid like water washing. In addition, since dust that normally floats in the air is taken into the mixed medium 20 and falls as it is, dust scattering can also be prevented. Furthermore, since the repulsive force is also absorbed by the liquid, the mixed medium 20 hardly rebounds. Due to such characteristics, the equipment of the operator 22 handling the blasting device 10 as shown in FIG.

  FIG. 1 shows a diagram in which the operator 22 holds the hose 26 near the nozzle 24 of the blasting apparatus 10 with both hands and projects the mixed medium 20 toward the ground 14. The worker 22 is lightly equipped without the need to equip the entire body with a protector unlike the sandblasting method. Thereby, the labor of the operator 22 is significantly reduced.

  The blast device 10 includes a tank 28, a blast medium supply device (blast medium supply unit) 30, a hose 26, a nozzle 24, an air compressor (compressed air supply unit) 32, and a liquid supply unit 38 including a liquid tank 34 and a flow rate adjusting valve 36. Etc.

  The tank 28 stores the calcium carbonate powder 16 as a blast medium, and a supply port 29 for the calcium carbonate powder 16 is formed below the hopper portion 28A. Although the formation position of the supply port 29 is not limited to the lower part of the hopper portion 28A, it is preferable to form the supply port 29 at this position because the calcium carbonate powder 16 can be supplied to the hose 26 by its own weight. The tank 28 is a direct pressure tank to which pressure is applied by compressed air from the air compressor 40.

  The hose 26 has a predetermined length, a base end portion 26A is connected to a supply port 29 of the tank 28 via a substantially cross-shaped joint pipe 42, and a nozzle 24 is connected to a tip end portion 26B of the hose 26. Yes.

  The air compressor 32 is connected to the joint pipe 42, and supplies compressed air to the base end portion 26 </ b> A of the hose 26 through the joint pipe 42.

  As described above, the liquid supply unit 38 includes the liquid tank 34 and the flow rate adjustment valve 36, and the liquid stored in the liquid tank 34 connects the joint pipe 42 to the base end portion 26 </ b> A of the hose 26 via the flow rate adjustment valve 36. Supplied through. In addition, the liquid supply amount is controlled by controlling the opening degree of the flow rate adjusting valve 36 by a control unit described later.

  The liquid supply position in the joint pipe 42 is set to the downstream end position (blast medium supply point) of the blast medium supply apparatus as shown in FIG. As a result, the liquid is directly supplied to the calcium carbonate powder 16 supplied from the supply port 29.

  The blast medium supply device 30 is a screw provided in the joint pipe 42 along the horizontal axis direction of the joint pipe 42. When the blast medium supply device 30 is driven to rotate, the calcium carbonate powder 16 stored in the tank 28 is forcibly scraped from the supply port 29 by a screw and guided to the hose 26. Further, the scraped calcium carbonate powder 16 is mixed with the liquid by the mixing action of the blast medium supply device 30 to become the mixed medium 20 and is pumped toward the nozzle 24 by the compressed air from the air compressor 32. Is done. The mixed medium 20 is further mixed with compressed air while being pumped and is mixed with the calcium carbonate powder 16 before the liquid is projected from the nozzle 24. In order to generate such a mixed medium 20, the supply amount of the calcium carbonate powder 16 by the blast medium supply device 30 and the supply amounts of the liquids are respectively set to suitable values. The blast medium supply device 30 may be disposed vertically below the supply port 29 of the tank 28 along the axis of the hopper portion 28A. Further, the rotational speed of the blast medium supply device 30 is controlled by a control unit described later, and the supply amount of the calcium carbonate powder 16 is thereby controlled.

  Next, the operation of the blasting apparatus 10 configured as described above will be described.

  The basic operation of the blasting apparatus 10 is that the calcium carbonate powder 16 and the liquid are mixed by the blast medium supply apparatus 30 on the base end portion 26A side of the hose 26, and the mixed medium 20 of the mixed calcium carbonate powder 16 and liquid is mixed. Is to be pneumatically transported through the hose 26 with compressed air and projected from the nozzle 24 at the tip of the hose 26 toward the ground 14. That is, the mixed medium 20 is accelerated from the base end portion 26 </ b> A of the hose 26 and is projected from the nozzle 24 toward the substrate 14 at a high speed.

  Therefore, the mixed medium 20 is projected without being decelerated at the position of the nozzle 24. In addition, since the mixing area becomes longer by passing the calcium carbonate powder 16 and the liquid through the hose 26, the mixing of the calcium carbonate powder 16 and the liquid is surely performed. Due to this mixing action, the liquid soaks into the calcium carbonate powder 16 satisfactorily, so that the liquid is not directly projected from the nozzle 24, and the calcium carbonate powder 16 soaked with the liquid is projected from the nozzle 24.

  By the above operation, the generation of dust due to the projected calcium carbonate powder 16 can be suppressed, and the contamination of the ground surface 14 is removed by the liquid soaked in the calcium carbonate powder 16 like water washing. Can be implemented efficiently. In addition, since the liquid soaks into the calcium carbonate powder 16 and is not projected by the liquid alone, the generation of secondary waste (water) can be suppressed.

  On the other hand, the used mixed medium 20 that has been dropped by blasting is lumped because the liquid is entangled. Thereby, it becomes easy to collect compared with water. Further, since the collected mixed medium 20 contains contamination (radioactive contaminants), it is preferable to store it in a cask and store it in an existing radiation control area. This eliminates the need for a secondary waste water treatment facility as compared with water containing radioactive pollutants, and makes handling of waste much easier.

  In the embodiment, powdery calcium carbonate powder 16 is used as the blasting medium. However, if the calcium carbonate powder 16 has a high hardness (for example, Mohs hardness of 6 or more), it is difficult to grind the coating film. Work can be done. Further, if the hardness is low (for example, less than Mohs hardness 6), soft work such as decontamination work or mirror finishing can be performed as in the embodiment. Furthermore, by using a pulverized shell such as scallop as the calcium carbonate powder 16, a powdery blasting medium suitable for protecting global environmental resources can be obtained. The calcium carbonate powder 16 may be industrially produced.

FIG. 2 is a schematic diagram showing an example of an operation method of the blasting apparatus 10 according to the embodiment. The basic idea of this operation method is in a clean house (blast target room) 44 in which the blasting apparatus 10 is used. The amount of dust is detected by a particle sensor (detection means) 46 (46A to 46F), and based on the detected amount of dust, the supply amount of calcium carbonate powder 16 by the blast medium supply unit 30 and / or the flow rate adjustment valve 36. The liquid supply amount is controlled by the control unit 48.

  That is, in this operation method, when the detected dust amount exceeds a specified value (a constant value) at which dust is determined to be generated, for example, the opening degree of the flow rate adjusting valve 36 is largely controlled to increase the liquid supply amount to increase dust. Suppresses the occurrence of Thereby, the blasting work environment in the clean house 44 can be satisfactorily and automatically maintained. Further, if the dust amount is significantly smaller than the specified value, the liquid may be projected alone. Therefore, the opening degree of the flow rate adjusting valve 36 is controlled to be small, and the liquid supply amount is reduced to perform the single liquid projection. To prevent. The object to be controlled by the control unit 48 is not limited to the flow rate adjusting valve 36, and may be controlled by increasing or decreasing the supply amount of the calcium carbonate powder 16 by controlling the blast medium supply unit 30. Both supply amounts may be controlled as described above. Thereby, the blasting operation can be performed efficiently in the clean house 44. 2 is an exhaust duct connected to the exhaust port 45 of the clean house 44, reference numeral 52 is an exhaust fan connected to the exhaust duct 50, and reference numeral 54 is a minute passage through the exhaust duct 50. It is a HEPA filter that removes particles and the like.

  By the way, according to this operation method, as shown in FIG. 2, the particles substantially along the path from the wall surface (projected portion) 12 on which the blast medium in the clean house 44 is projected to the exhaust port 45 of the clean house 44. A plurality (six in FIG. 2) of sensors 46A to 46F are provided. Then, at the start of projection of the mixed medium 20, the control unit 48 detects the dust amount by, for example, two particle sensors 46 </ b> E and 46 </ b> F in the vicinity of the exhaust port 45 separated from the wall surface 12 and obtains the average. When the average amount of dust is larger than the specified value, the control unit 48 controls the flow rate adjustment valve 36 so that the amount of liquid supplied is increased and the amount of dust is smaller than a predetermined value. / Or the amount of dust is suppressed by controlling the blast medium supply unit 30 so that the supply amount of the mixed medium 20 is reduced to be smaller than the predetermined value.

  At the initial stage of projection of the mixed medium 20, the amount of air hitting the wall surface 12 is still small, and the amount of air reflected and flowing to the exhaust port 45 and the amount of dust are also small. Therefore, if the number of particle sensors is six, for example, the amount of dust is detected by the two particle sensors 46E and 46F close to the exhaust port 45, the average is taken, and this value is taken as the amount of dust. When the amount of dust is larger than the specified value, the amount of moisture is increased and control is performed to reduce the amount of dust.

  If the amount of dust is still greater than the specified value after the predetermined time has elapsed, the supply amount of the calcium carbonate powder 16 is further reduced. If the liquid increases due to this, the wall 12 and floor of the clean house 44 become sticky with the liquid and the calcium carbonate powder 16, so the air compressor 32 is controlled next to reduce the amount of compressed air. That is, the amount of dust is reduced by sequentially or simultaneously performing the above three controls.

  Further, when the projection of the mixed medium 20 has elapsed for a predetermined time and the air amount per hour and the dust amount increase, the control unit 48 also increases the air amount and dust amount reflected on the wall surface 12. The number of operation of the particle sensors 46A to 46F is sequentially increased from the downstream side to the upstream side of the path in proportion to the air amount converted from the pressure. When the amount of air per hour is the largest, all the particle sensors 46A to 46F are operated. On the other hand, when the average value is acquired with the dust amounts of all the particle sensors 46A to 46F when the air amount is small, the dust amount on the upstream side of the path with the small dust amount is also used as the calculated value. Less than the amount of dust. Therefore, as described above, by increasing the number of particle sensors 46A to 46F that operate according to the progress of the projection time sequentially from the downstream side to the upstream side of the path, the accuracy of dust amount detection increases.

  On the other hand, if the simple water is used as the liquid, the ground 14 is rusted, so it is preferable to use alkaline electrolyzed water (pH 11 or more). Moreover, it is preferable to mix this alkaline surfactant. Thereby, it becomes easy to remove the contamination on the ground surface, so that a high decontamination effect can be obtained. In addition, when a decontamination target object is aluminum, neutral surfactant is used.

  Moreover, the blasting apparatus 10 of embodiment can be used also in the coating-film removal process performed before the decontamination process of the foundation | substrate 14. In this case, it is preferable to use an abrasive such as copper slag (calami), steel grit, alumina, zirconia, etc. having high hardness as the blast medium.

Explanatory drawing which showed the whole structure of the blasting apparatus of embodiment Schematic showing an example of the operation method of the blasting device

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Blast apparatus, 12 ... Wall surface of nuclear power plant equipment, 14 ... Ground surface, 20 ... Mixed medium, 22 ... Worker, 24 ... Nozzle, 26 ... Hose, 28 ... Tank, 30 ... Blast medium supply apparatus, 32 ... Air compressor 34 ... Liquid tank 36 ... Flow control valve 38 ... Liquid supply part 40 ... Air compressor 42 ... Joint pipe 44 ... Clean house 46 ... Particle sensor 48 ... Control part 50 ... Exhaust duct 52 ... Exhaust fan, 54 ... HEPA filter

Claims (8)

A tank in which a blast medium is stored and a blast medium supply port is formed at a predetermined position, a hose having a base end connected to the supply port of the tank, and a tip of the hose A nozzle, a compressed air supply unit that supplies compressed air to the base end of the hose, and a supply point of the blast medium that is connected to the base end of the hose and supplied from the supply port of the tank In a blasting apparatus comprising a liquid supply unit for supplying a liquid,
The amount of dust in the blast target chamber in which the blasting device is used is detected by a detection means, and based on the detected amount of dust, the blasting medium supply amount by the blasting medium supply unit of the blasting device and / or the liquid supply unit A blasting apparatus characterized by controlling the liquid supply amount by the control unit. A plurality of the detection means are provided substantially along a path from the projected portion on which the blast medium in the blast target chamber is projected to the exhaust port of the blast target chamber,
At the start of projection of the blast medium, the control unit obtains the average by detecting the dust amount by a plurality of detection means in the vicinity of the exhaust port separated from the projection portion, and the average dust amount is If larger than a certain value, the liquid supply unit is controlled to increase the liquid supply amount so that the dust amount becomes smaller than the certain value, and / or the blast medium supply amount is decreased to reduce the dust amount. The blasting apparatus according to claim 1, wherein the blasting medium supply unit is controlled to be smaller than a certain value.   The control unit sequentially increases the number of detection means to be operated from the downstream side to the upstream side of the path when the blast medium projection has elapsed for a predetermined time, and when the amount of air per hour is the largest, all the detection means The blasting device according to claim 2, wherein the blasting device is operated. A tank in which a blast medium is stored and a blast medium supply port is formed at a predetermined position, a hose having a base end connected to the supply port of the tank, and a tip of the hose A nozzle, a compressed air supply unit that supplies compressed air to the base end of the hose, and a supply point of the blast medium that is connected to the base end of the hose and supplied from the supply port of the tank In an operation method of a blasting apparatus including a liquid supply unit for supplying a liquid,
The amount of dust in the blast target chamber in which the blasting device is used is detected by a detection means, and based on the detected amount of dust, the blasting medium supply amount by the blasting medium supply unit of the blasting device and / or the liquid supply unit A method for operating a blasting apparatus, characterized in that a liquid supply amount by the control unit is controlled by a control unit. A plurality of the detection means are provided substantially along a path from the projected portion on which the blast medium in the blast target chamber is projected to the exhaust port of the blast target chamber,
At the start of projection of the blast medium, the control unit obtains the average by detecting the dust amount by a plurality of detection means in the vicinity of the exhaust port separated from the projection portion, and the average dust amount is If larger than a certain value, the liquid supply unit is controlled to increase the liquid supply amount so that the dust amount becomes smaller than the certain value, and / or the blast medium supply amount is decreased to reduce the dust amount. The operation method of the blasting apparatus according to claim 4, wherein the blast medium supply unit is controlled to be smaller than a certain value.   The control unit sequentially increases the number of detection means to be operated from the downstream side to the upstream side of the path when the blast medium projection has elapsed for a predetermined time, and when the amount of air per hour is the largest, all the detection means The operation method of the blasting device according to claim 5, wherein the blasting device is operated.   The method for operating a blasting apparatus according to claim 4, wherein the blasting medium is a powdery medium.   The operation method of the blasting apparatus according to claim 7, wherein the powdery medium is calcium carbonate powder.

Images