Furnace monitoring device and gasification unit provided with same

A furnace monitoring device for monitoring the inside of a gasifier through which a combustible gas flows is provided with: a nozzle that has an internal cavity, and that is inserted inside the gasifier and fixed to the gasifier; a cylindrical protection tube which is inserted into the nozzle, and a part of which, located on the inside of the gasifier is, blocked; a monitoring window which is provided on the protection tube on the inside of the gasifier, and is made of a material that transmits light; a purge mechanism which supplies a gas containing an oxidizer to a surface of the monitoring window facing the inside of the gasifier; and an image capturing means which captures an image of the inside of the gasifier through the monitoring window.

TECHNICAL FIELD

The present invention relates to a furnace monitoring device and a gasification unit provided with the same.

BACKGROUND ART

In the related art, as a gasification unit, a carbonaceous fuel gasification unit (gasification unit) is known, which supplies carbonaceous feedstock such as coal into a gasifier and partially combusts the carbonaceous feedstock to gasify the carbonaceous feedstock so as to generate a combustible gas. A furnace monitoring device for monitoring a situation in a furnace is provided in the gasification unit (for example, PTL 1).

PTL 1 discloses the furnace monitoring device including a cooling fluid passage which passes through an equipment housing portion housing a camera and a cleaning fluid passage which cleans a monitoring window which separates the inside of the furnace from the equipment housing portion. In the furnace monitoring device disclosed in PTL 1, air flows through the cooling fluid passage to cool an imaging device, and cleaning air or washing water blows from an ejection hole disposed at a tip of the cleaning fluid passage toward the monitoring window to clean the monitoring window.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

Here, as described in PTL 1, in a case where the cleaning air blows to protect the monitoring window, if an oxygen containing gas such as oxygen is contained in the cleaning air, the cleaning air reacts with a combustible gas filling the inside of the gasifier, and thus, intense light is emitted. For this reason, there is a problem that a field of view of the furnace monitoring device is obstructed. In addition, in a case where the cleaning air is an inert gas, a solid in the furnace is solidified around the monitoring window and is accumulated around a monitoring region.

The present invention is made in consideration of the above-described problems, and an object thereof is to provide a furnace monitoring device capable of monitoring an inside of a furnace and a gasification unit provided with the same.

Solution to Problem

In order to solve the above-described problems, according to an aspect of the present invention, there is provided a furnace monitoring device which monitors an inside of a gasifier through which a combustible gas flows, including: a nozzle which is inserted into the gasifier, is fixed to the gasifier, and has an internal cavity; a protection tube which is formed in a tubular shape, is inserted into the nozzle, and has a blocked portion which is positioned inside the gasifier; a monitoring window which is provided on a portion of the protection tube inside the gasifier and transmits light; a purge mechanism which supplies a gas including an oxygen containing gas to a surface of the monitoring window inside the gasifier; and imaging means for imaging the inside of the gasifier via the monitoring window, in which the imaging means includes an imaging device which images the inside of the gasifier via the monitoring window, an optical filter which shields a wavelength of light emitted from a radical, and an optical filter switching unit which attaches the optical filter to the imaging device or detaches the optical filter from the imaging device.

According to this configuration, the optical filter which does not transmit the radical emission wavelength is attached to the imaging device, and thus, it possible to selectively shield the light from the radical emission to be incident on the imaging device, and thus, it is possible to monitor the inside of the gasifier even in a case where the radical emission is generated.

In addition, preferably, the optical filter transmits only a wavelength within a range from 759 nm to 928 nm.

According to this configuration, even in a case where an inside of a high-temperature gasifier filled with the combustible gas is purged by the gas including the oxygen containing gas, it is possible to prevent the emitted light of O2 radical and H2O radical from transmitting the optical filter and to monitor the inside of the gasifier with clearer images.

Moreover, preferably, the furnace monitoring device further includes control means which is connected to the optical filter switching unit, in which the control means attaches the optical filter to the imaging device in a case where a gas discharge temperature of the gasifier exceeds a preset value or a fuel is introduced into the gasifier, and the control means detaches the optical filter from the imaging device in a case where the gas discharge temperature of the gasifier is equal to or less than the preset value and the fuel is not introduced into the gasifier.

According to this configuration, in the case where the gasifier outlet gas thermometer exceeds the preset value or in the case where the burner inlet cutoff valve is opened, the control means controls the optical filter switching unit, and thus, the optical filter which does not transmit the radical emission wavelength is attached to the imaging device. Accordingly, it possible to selectively shield the light from the radical emission to be incident on the imaging device, and thus, it is possible to monitor the inside of the gasifier even in the case where the radical emission is generated.

According to this configuration, in the case where the gasifier outlet gas thermometer is equal to or less than the preset value or in the case where the burner inlet cutoff valve is closed, the control means controls the optical filter switching unit to detach the optical filter from the imaging device. Accordingly, it is possible to prevent luminance of the light incident on the imaging device from being decreased by the optical filter, and it is possible to monitor the inside of the gasifier even in a case where the luminance in the gasifier is not sufficient when the gasifier starts or stops.

In addition, preferably, the furnace monitoring device includes a lighting device which illuminates the inside of the gasifier via the monitoring window.

According to this configuration, it is possible to illuminate the inside of the gasifier, and it is possible to monitor the inside of the gasifier even in a case where the luminance in the gasifier is not sufficient when the gasifier starts or stops.

Moreover, preferably, the furnace monitoring device further includes a pressure resistance tube which is formed in a cylindrical shape and is inserted into the protection tube; a transparent window which is provided on an end portion of the pressure resistance tube on the gasifier side to shield a space inside the protection tube and a space inside the pressure resistance tube and transmit light, a fiberscope which is accommodated in the pressure resistance tube, and a mirror which is disposed between the monitoring window and the transparent window and reflects light incident from the monitoring window to be incident on the transparent window, the monitoring window is formed on a side surface of a portion of the protection tube inserted into the gasifier, and the purge mechanism supplies the gas including the oxygen containing gas to a space between the protection tube and the pressure resistance tube, and blows out the gas including the oxygen containing gas from the monitoring window.

According to this configuration, the light incident from the monitoring window is reflected toward the fiberscope by the mirror, and the light incident on the fiberscope is transmitted to the lens of the imaging device by the fiberscope. Therefore, it is possible to image the inside of the gasifier from the side wall of the protection tube, it is possible to minimize an insertion depth of the protection tube, and a fluid friction generated between the gas flow inside the gasifier and the protection tube can be suppressed so as to be minimized. In addition, it is possible to transmit the light incident on the monitoring window from the inside of the gasifier to a location away from the gasifier such that a disposition position of the imaging device can be separated from the gasifier, it is possible to prevent the imaging device from being exposed to a high temperature, and a heat resistant temperature of the imaging device can be lowered.

In addition, preferably, the furnace monitoring device further includes a valve which is attached to the nozzle and shields the inside and an outside of the gasifier, a cylindrical vessel which is connected to the nozzle and shields a periphery of the protection tube from an outside; and a movement mechanism which moves the protection tube with respect to the cylindrical vessel.

According to this configuration, even in a case where trouble occurs in the furnace monitoring device during the operation of the gasification unit and maintenance is required, it is possible to attach the furnace monitoring device to the gasification unit or to detach the furnace monitoring device from the gasification unit without stopping the gasification unit, and it is possible to improve an operation rate of the gasification unit.

In addition, in order to solve the above-described problems, according to another aspect of the present invention, there is provided a gasification unit including any one of the above-described furnace monitoring devices.

Advantageous Effects of Invention

According to the present invention, it is possible to monitor the inside of the furnace even in a case where the inside of the high-temperature furnace filled with the combustible gas containing particles is purged by the gas including the oxygen containing gas.

DESCRIPTION OF EMBODIMENTS

FIG. 1is a schematic configuration diagram of an integrated coal gasification combined cycle to which a gasification unit according to a first embodiment is applied.FIG. 2is a schematic configuration diagram showing the gasification unit according to the first embodiment.FIG. 3is a cross-sectional diagram of a furnace monitoring device200aaccording to the first embodiment.

In an integrated coal gasification combined cycle (IGCC)10to which a gasification unit14according to the present embodiment is applied, air is used as an oxygen containing gas, and the gasification unit14adopts an air combustion method which generates a combustible gas (raw syngas) from a fuel. In addition, in the integrated coal gasification combined cycle10, the raw syngas generated by the gasification unit14is purified by a gas clean-up unit16to obtain a fuel gas, and thereafter, is supplied to a gas turbine17for power generation. That is, the integrated coal gasification combined cycle10of the first embodiment is an air combustion type (air blowing) power generating facility. For example, carbonaceous feedstock such as coal is used as the fuel supplied to the gasification unit14.

As shown inFIG. 1, the integrated coal gasification combined cycle (integrated gasification combined cycle)10includes a coal supply unit11, the gasification unit14, a char recovery unit15, the gas clean-up unit16, the gas turbine17, a steam turbine18, a generator19, and a heat recovery steam generator (HRSG)20.

Coal which is carbonaceous feedstock as raw coal is supplied to the coal supply unit11, and the coal supply unit II pulverizes the coal by a coal mill (not shown) or the like to produce pulverized coal pulverized into fine particles. The pulverized coal produced by the coal supply unit11is pressurized by a nitrogen gas serving as a carrier inert gas supplied from an air separation unit42to be described later at an outlet of the coal supply line11a and is supplied to the gasification unit14. The inert gas is an inert gas having an oxygen content of approximately 5 vol % or less, and a nitrogen gas, a carbon dioxide gas, an argon gas, or the like is representative as the inert gas. However, in the inert gas, the oxygen content is not necessarily limited to approximately 5% or less.

The pulverized coal produced by the coal supply unit11is supplied to the gasification unit14, and a char (an unreacted portion and an ash content of the coal) recovered by the char recovery unit15is returned so as to be supplied reusably to the gasification unit14.

In addition, a compressed air supply line41from the gas turbine17(compressor61) is connected to the gasification unit14, and thus, a portion of air compressed by the gas turbine17is boosted to a predetermined pressure by a booster68so as to be supplied to the gasification unit14. The air separation unit42separates and generates nitrogen and oxygen from the air in the atmosphere, and the air separation unit42and the gasification unit14are connected to each other by a first nitrogen supply line43. In addition, a coal supply line11a from the coal supply unit11is connected to the first nitrogen supply line43. Moreover, a second nitrogen supply line45branching off from the first nitrogen supply line43is also connected to the gasification unit14, and a char return line46from the char recovery unit15is connected to the second nitrogen supply line45. In addition, the air separation unit42is connected to the compressed air supply line41via the oxygen supply line47. Moreover, nitrogen separated by the air separation unit42flows through the first nitrogen supply line43and the second nitrogen supply line45and thus, is used as a carrier gas of the coal or the char. In addition, oxygen separated by the air separation unit42flows through the oxygen supply line47and the compressed air supply line41, and thus, is used as the oxygen containing gas in the gasification unit14.

For example, the gasification unit14includes a two-stage entrained bed type gasifier101(refer toFIG. 2). In the gasification unit14, the coal (pulverized coal) and the char supplied into the inside thereof are partially combusted by the oxygen containing gas (air and oxygen) to be gasified so as to be the raw syngas. In addition, the gasification unit14includes a foreign matter removal unit48which removes foreign matters (slag) mixed into the pulverized coal. In addition, a gas generation line49through which the raw syngas is supplied to the char recovery unit15is connected to the gasification unit14, and the raw syngas including the char can be discharged from the gasification unit14. As shown inFIG. 2, in this case, a syngas cooler102(gas cooler) may be provided in the gas generation line49such that the raw syngas is supplied to the char recovery unit15while being cooled to a predetermined temperature.

The char recovery unit15includes a dust collection unit51and a supply hopper52. In this case, the dust collection unit51is configured of one or a plurality of cyclones or porous filters, and can separate the char contained in the raw syngas generated by the gasification unit14. In addition, the raw syngas from which the char has been separated is fed to the gas clean-up unit16through a gas discharge line53. The supply hopper52stores the char which is separated from the raw syngas by the dust collection unit51. In addition, a bin may be disposed between the dust collection unit51and the supply hopper52such that a plurality of supply hoppers52are connected to the bin. In addition, the char return line46from the supply hopper52is connected to the second nitrogen supply line45.

The gas clean-up unit16removes impurities such as sulfur compounds and nitrogen compounds from the raw syngas from which the char has been separated by the char recovery unit15so as to perform gas purification. In addition, the gas clean-up unit16purifies the raw syngas to produce the fuel gas and supplies the fuel gas to the gas turbine17. In addition, a sulfur content (H2S, etc.) is still contained in the raw syngas from which the char has been separated, and thus, the gas clean-up unit16removes and recovers the sulfur content by using an amine absorbing solution and uses it effectively.

The gas turbine17includes the compressor61, a combustor62, and a turbine63, and the compressor61and the turbine63are connected by a rotary shaft64. The compressed air supply line41from the compressor61is connected to the combustor62, a fuel gas supply line66from the gas clean-up unit16is connected to the combustor62, and a combustion gas supply line67which extends toward the turbine63is connected to the combustor62. In addition, the compressed air supply line41extending from the compressor61to the gasification unit14is provided in the gas turbine17, and the booster68is provided in an intermediate portion of the compressed air supply line41. Accordingly, in the combustor62, a portion of the compressed air supplied from the compressor61and at least a portion of the fuel gas supplied from the gas clean-up unit16are mixed with each other to be combusted so as to generate a combustion gas, and the generated combustion gas is supplied to the turbine63. In addition, in the turbine63, the rotary shaft64is rotationally driven by the supplied combustion gas, and thus, the generator19is rotationally driven.

The steam turbine18includes a turbine69which is connected to the rotary shaft64of the gas turbine17, and the generator19is connected to a base end portion of the rotary shaft64. A flue gas line70from the gas turbine17(turbine63) is connected to the heat recovery steam generator20, and the heat recovery steam generator20performs heat exchange between supplied water and a flue gas of the turbine63so as to generate steam. In addition, a steam supply line71and a steam recovery line72are provided between the heat recovery steam generator20and the turbine69of the steam turbine18, and a condenser73is provided in the steam recovery line72. In addition, the steam generated by the heat recovery steam generator20may include the steam generated by the heat exchange with the raw syngas by the syngas cooler102of the gasifier101. Accordingly, in the steam turbine18, the turbine69is rotationally driven by the steam supplied from the heat recovery steam generator20, the rotary shaft64is rotated, and thus, the generator19is rotationally driven.

In addition, a gas purifying unit74is provided from an outlet of the heat recovery steam generator20to a stack75.

Here, an operation of the integrated coal gasification combined cycle10of the present embodiment will be described.

In the integrated coal gasification combined cycle10of the present embodiment, if the raw coal (coal) is supplied to the coal supply unit11, the coal is pulverized into fine particles in the coal supply unit11so as to be the pulverized coal. The pulverized coal produced by the coal supply unit11flows through the first nitrogen supply line43by the nitrogen supplied from the air separation unit42so as to be supplied to gasification unit14. In addition, the char recovered by the char recovery unit15described later flows through the second nitrogen supply line45by the nitrogen supplied from the air separation unit42so as to be supplied to the gasification unit14. In addition, the compressed air bled from the gas turbine17described later is boosted by the booster68, and thereafter, is supplied to the gasification unit14through the compressed air supply line41along with the oxygen supplied from the air separation unit42.

In the gasification unit14, the supplied pulverized coal and the char are combusted by the compressed air (oxygen), the pulverized coal and the char are gasified, and thus, the raw syngas is generated. In addition, the raw syngas is discharged through the gas generation line49from the gasification unit14and is fed to the char recovery unit15.

In the char recovery unit15, first, the raw syngas is supplied to the dust collection unit51, and thus, fine char contained in the raw syngas is separated. In addition, the raw syngas from which the char has been separated is fed to the gas clean-up unit16through the gas discharge line53. Meanwhile, the fine char separated from the raw syngas is accumulated in the supply hopper52and is returned to the gasification unit14through the char return line46so as to be recycled.

The gas clean-up unit16removes impurities such as sulfur compounds and nitrogen compounds from the raw syngas from which the char has beer, separated by the char recovery unit15so as to perform the gas purification, and thus, the fuel gas is produced. The compressor61generates the compressed air so as to supply to the combustor62. The combustor62mixes the compressed air supplied from the compressor61and the fuel gas supplied from the gas clean-up unit16with each other and combusts the mixture to generate the combustion gas. The turbine63is rotationally driven by the combustion gas, and thus, rotationally drives the compressor61and the generator19via the rotary shaft64. In this way, the gas turbine17can generate electricity.

Moreover, the heat recovery steam generator20performs heat exchange between the flue gas discharged from the turbine63and the supplied water in the gas turbine17so as to generate steam, and supplies the generated steam to the steam turbine18. In the steam turbine18, the turbine69is rotationally driven by the steam supplied from the heat recovery steam generator20, and thus, the generator19is rotationally driven via the rotary shaft64so as to generate electricity.

In addition, the gas turbine17and the steam turbine18need not rotate and drive one generator19as the same shaft, and a plurality of generators may be rotationally driven by shafts different from each other.

Thereafter, in the gas purifying unit74, harmful substances of an exhaust gas discharged from the heat recovery steam generator20are removed, and the purified exhaust gas is released from the stack75to the atmosphere.

Next, with reference toFIGS. 1 and 2, the gasification unit14in the integrated coal gasification combined cycle10will be described in detail.

As shown inFIG. 2, the gasification unit14includes the101, the syngas cooler102, a control means130, and a furnace monitoring device200a. The control means130has a function of a control means of the furnace monitoring device200a.

The gasifier101is formed to extend in a vertical direction, and the pulverized coal and the oxygen are supplied to a lower side in the vertical direction so as to be partial combusted, and the gasified combustible gas (raw syngas) flows from the lower side in the vertical direction toward the upper side. The gasifier101includes a pressure vessel110and a gasifier wall111which is provided inside the pressure vessel110. In addition, in the gasifier101, an annulus portion115is formed in a space between the pressure vessel110and the gasifier wall111. In addition, in the gasifier101, in the space inside the gasifier wall111, a combustor portion116, a diffuser portion117, and a reductor portion118are formed in this order from the lower side (that is, an upstream side in a flow direction of the raw syngas) in the vertical direction.

The pressure vessel110is formed in a tubular shape whose internal portion is a hollow space, a gas discharge port121is formed on an upper end portion of the pressure vessel110, and a slag hopper122is formed on a lower end portion (bottom portion) thereof. A gasifier outlet gas thermometer125is disposed in in the gas discharge port121. The gasifier wall111is formed in a tubular shape whose internal portion is a hollow space, and a wall surface of the gasifier wall111is provided to face an inner surface of the pressure vessel110. Moreover, the gasifier wall111is connected to an inner surface of the pressure vessel110by a support member (not shown).

The gasifier wall111is formed by joining a heat transfer tube (not shown) and a fin (not shown) to each other by welding or the like. In addition, an upper end portion of the gasifier wall111is connected to the gas discharge port121of the pressure vessel110, and a lower end portion of the gasifier wall111is provided with a gap between the lower end portion and a bottom portion of the pressure vessel110. In addition, water is stored in the slag hopper122formed on a bottom portion of the pressure vessel110, the stored water enters the lower end portion of the gasifier wall111, and thus, the inside and the outside of the gasifier wall111are sealed.

The annulus portion115is a space which is formed inside the pressure vessel110and outside the gasifier wall111, and the nitrogen which is an inert gas separated by the air separation unit42is supplied to the annulus portion115through a nitrogen supply line (not shown). Accordingly, the annulus portion115is a space which is filled with the nitrogen. In addition, a furnace internal pressure equalizing pipe (not shown) for equalizing the inside of the gasifier101is provided near the upper portion of the annulus portion115in the vertical direction. The furnace internal pressure equalizing pipe is provided to communicate with the inside and the outside of the gasifier wall111and equalizes the inside (combustor portion116, diffuser portion117, and reductor portion118) and the outside (annulus portion115) of the gasifier wall111.

The combustor portion116is a space in which the pulverized coal, the char, and the air are partially combusted, and a combustion device configured of a plurality of burners126is disposed in the gasifier wall111in the combustor portion116. The fuel is supplied to the plurality of burners126via a burner inlet cutoff valve129. A portion of the pulverized coal and the char is partially combusted in the combustor portion116, and thus, a generated high-temperature combustion gas passes through the diffuser portion117and flows into the reductor portion118.

The reductor portion118is a space in which a high-temperature state required for a gasification reaction is maintained, the pulverized coal is supplied to the combustion gas from the combustor portion116, and the pulverized coal is thermally decomposed into volatile components (carbon monoxide, hydrogen, lower hydrocarbon, or the like) to be gasified so as to generate the combustible gas. A combustion device configured of plurality of burners127is disposed in the gasifier wall111in the reductor portion118. The fuel is supplied to the plurality of burners127via a burner inlet cutoff valve128.

The syngas cooler10215Provides inside the gasifier wall111and is provided vertically above the burner127of the reductor portion118. In the syngas cooler102, an evaporator131, a superheater132, and an economizer134are disposed in t is order from a vertically lower side (the upstream side in a flow direction of the raw syngas) of the gasifier wall111. The syngas cooler102performs heat exchange with the raw syngas generated in the reductor portion118so as to cool the raw syngas. In addition, the evaporator131, the superheater132, and the economizer134are not limited to the number described in the drawing.

The control means130is connected to the gasifier outlet gas thermometer125, the burner inlet cutoff valve128, the burner inlet cutoff valve129, and the furnace monitoring device200adescribed later.

The furnace monitoring device200ais a device which monitors the inside of the gasifier101. The furnace monitoring device200awill be described later.

Here, an operation of the gasification unit14of the above-described first embodiment will be described. In the gasifier10z f the gasification unit14, the nitrogen and the pi-liven-zed coal are injected and ignited by the burner127of the reductor portion118, and the char and the compressed air (oxygen) are injected and ignited by the burner125of the combustor portion116. Accordingly, in the combustor portion116, the high-temperature combustion gas is generated by partial combustion of the pulverized coal and the char. In addition, in the combustor portion116, a molten slag is generated in the high-temperature gas by the combustion of the pulverized coal and the char, and the molten slag is attached to the, gasifier wall111, falls to a furnace bottom, and is finally discharged to the stored water in the slag hopper122. In addition, the high-temperature combustion gas generated in the combustor portion116rises to the reductor portion118through the diffuser portion117. In the reductor portion118, a high-temperature state required for the gasification reaction is maintained, the pulverized coal is mixed with the high-temperature combustion gas, the pulverized coal is thermally decomposed into volatile components (carbon monoxide, hydrogen, lower hydrocarbons, or the like) in a high-temperature reducing atmosphere field so as to perform the gasification reaction, and thus, the combustible gas (raw syngas) is generated. The gasified combustible gas (raw syngas) flows from the lower side in the vertical direction toward the upper side.

In addition, in the above-described embodiment, the case where the gasification unit14is applied to the integrated coal gasification combined cycle10is described. However, the gasification unit14may be applied to a plant other than the integrated coal gasification combined cycle10, for example, a gasifier of a garbage incineration plant and a gasifier of a chemical synthesis plant.

Moreover, in the above-described embodiment, the coal is used as the fuel. However, high rank coal and low rank coal can be used, and the fuel is not limited to the coal. That is, the fuel may be biomass which is used as a renewable organism-derived organic resource, and, for example, the fuel may be thinned wood, waste wood, driftwood, grasses, waste, sludge, tire, recycled fuel (pellets and chips) made from these as raw materials, or the like.

In addition, in the present embodiment, a tower type gasifier is described as the gasifier101. However, even when the gasifier101is a crossover type gasifier, by replacing the upper side and the lower side in the vertical direction of each device in the gasifier101so as to match the gas flow direction of the raw syngas, the crossover type gasifier can be used.

Next, with reference toFIG. 3in addition toFIG. 2, the furnace monitoring device200aaccording to the first embodiment of the present invention will be described. The furnace monitoring device200aincludes a protection tube202a, a nozzle212a, a monitoring window250a, imaging means252a, and the control means130.

The protection tube202ais a cylindrical pipe which accommodates the imaging means252a. The protection tube202aincludes an outer cylinder204a, a fluid flow path206a, an inner cylinder208a, and an opening224a. As shown inFIG. 3, the protection tube202ais inserted into the nozzle212a.

The nozzle212ais a nozzle which is formed to penetrate the gasifier wall111, the annulus portion115, and a pressure vessel110. The outer cylinder204ais a cylindrical pipe. The outer cylinder204aincludes a flange portion214a. The flange portion214ais fixed to the nozzle212a.

The fluid flow path206ais a fluid flow path which is formed between the outer cylinder204aand the inner cylinder208a. As shown inFIG. 3, an ejection hole226ais formed on an end portion of the fluid flow path206aon the inside222of the furnace. As shown inFIG. 3, a boss216ais formed on an end portion of the fluid flow path206aon the outside228of the furnace. The boss216ais connected to an air supply source220avia the air source valve218a. For example, the air supply source220ais a compressor. The air supply source220asupplies air to the fluid flow path206avia an air source valve218aand the boss216aand ejects the air from the ejection hole226aso as to perform purge.

The inner cylinder208aincludes a flange portion230aon the outside228of the furnace. A closing flange232ais attached to the flange portion230a. As shown inFIG. 3, a support member262afor fixing the imaging device254adescribed later is fixed to the inner cylinder208a. In addition, a fixing method is not particularly limited, and the support member262amay be fixed by welding or may be fastened to be fixed by a bolt, a nut, or the like.

As shown inFIG. 3, the opening224ais a circular opening which is formed at a center of a surface facing the protection tube202aon the inside222of the furnace.

The monitoring window250ais a window through which light is transmitted and includes the opening224a. In the monitoring window250aof the present embodiment, a transparent heat resistant member for transmitting light is disposed. The monitoring window250ablocks the opening224awith a transparent heat resistant member for transmitting light. For example, the transparent heat resistant member for transmitting light is a sapphire glass and a borosilicate glass. In the monitoring window250a, an outer peripheral portion thereof which is in contact with the inner cylinder200ais sealed, and thus, the inside of the gasifier101and the outside of the protection tube202aare shielded.

The imaging means252aincludes an imaging device254a, an optical filter256a, an optical filter switching unit258a, and a lighting device259a. The imaging device254ais a device which images the inside of the furnace via the monitoring window250a. For example, the imaging device254ais a CCD camera and a CMOS camera. The imaging device254ais accommodated inside the protection tube202a. The imaging device254aincludes a lens (not shown). As shown inFIG. 3, the imaging device254ais fixed to the support member262asuch that an optical axis260aof the lens (not shown) and the center of the opening224acoincide with each other. The imaging device254aoutputs an image imaged by an output cable (not shown) to a monitor of a central control room (not shown). The imaging device254ais connected to the control means130.

The optical filter256ais a filter which does not transmit a radical emission wavelength. Specifically, the radical emission wavelength is a wavelength included in the light emitted by radical in a case where a fuel containing carbon is combusted. For example, light emitted by CH radical has a band spectrum around 387 nm and 431 nm, and light emitted by O2 radical has a band spectrum near 759 nm. The optical filter256ais larger than the lens of the imaging device254a. That is, the optical filter256acan cover the lens of the imaging device254ain a case where the optical filter256ais attached to the imaging device254a. The optical filter256ais fixed to the optical filter switching unit258a.

As shown inFIG. 3, the optical filter switching unit258ais fixed to the inner cylinder208a. When the lens of the imaging device254ais viewed via the monitoring window250afrom the inside222of the furnace, the optical filter switching unit258ais an actuator which moves the optical filter256ato a position at which the optical filter256acovers the lens of the imaging device254aor a position at which the optical filter256adoes not overlap the lens of the imaging device254a. For example, the actuator is a servo motor. The optical filter switching unit258ais connected to the control means130.

As shown inFIG. 3, the lighting device259ais fixed to the imaging device254a. For example, the lighting device259ais LED lighting. The lighting device259ailluminates the inside of the furnace through the monitoring window250ain an irradiation direction directed to the monitoring window250a.

Here, an operation of the furnace monitoring device200aof the above-described first embodiment will be described. In the furnace monitoring device200aof the present embodiment, the air supply source220asupplies air to the fluid flow path206avia the air source valve218aand the boss216aso as to eject the air from the ejection hole226a. The air ejected from the ejection hole226ablows out particles attached to the monitoring window250aand the particles filling the inside222of the furnace of the monitoring window. The air ejected from the ejection hole226areacts with the combustible gas filling the inside of the gasifier101and emits light.

In a case where the gasifier outlet gas thermometer125exceeds a preset value or in a case where the burner inlet cutoff valves128and129are opened, the control means130operates the optical filter switching unit258ato attach the optical filter256ato the imaging device254a. Here, for example, the preset temperature is 1000° C. The optical-filter256ashields an inner radical emission wavelength component of the light incident from the inside222of the furnace via the monitoring window250a. That is, the optical filter256ashields the radical emission wavelength component of the light generated by the reaction between the air ejected from the election hole226aand the combustible gas. The imaging device254aimages light other than the radical emission wavelength transmitting the optical filter256a.

In a case where the gasifier outlet gas thermometer125is equal to or less than a preset value or in a case where the burner inlet cutoff valves128and129are closed, the control means130operates the optical filter switching unit258ato detach the optical filter256afrom the imaging device254a. Here, for example, the preset temperature is 1000° C.

In the furnace monitoring device200aaccording to the first embodiment, in the case where the gasifier outlet gas thermometer125exceeds the preset value or in the case where the burner inlet cutoff valves128and129are opened, the control means130controls the optical filter switching unit258a, and thus, the optical filter256awhich does not transmit the radical emission wavelength is attached to the imaging device254a. Accordingly, it possible to selectively shield the light from the radical emission to be incident on the imaging device254a, and thus, it is possible to monitor the inside of the gasifier101even in a case where the radical emission is generated.

In the furnace monitoring device200aaccording to the first embodiment, in the case where the gasifier outlet gas thermometer125is equal to or less than the preset value or in the case where the burner inlet cutoff valves128and129are closed, the control means130controls the optical filter switching unit258ato detach the optical filter256afrom the imaging device254a. Accordingly, it is possible to prevent luminance of the light incident on the imaging device254afrom being decreased by the optical filter256a, and it is possible to monitor the inside of the furnace even in a case where the luminance in the gasifier101is not sufficient when the gasifier starts or stops.

The furnace monitoring device200aaccording to the first embodiment includes the lighting device259a. Accordingly, it is possible to illuminate the inside of the gasifier101, and it is possible to monitor the inside of the furnace even in a case where the luminance in the gasifier101is not sufficient when the gasifier starts or stops.

It is preferable that the optical filter256ais an optical filter which transmits light having a wavelength of 800 nm to 900 nm, and it is more preferable that the optical filter256ais an optical filter which transmits light having a wavelength of 755 nm to 927 nm. Accordingly, even in a case where the inside of the high-temperature furnace filled with the combustible gas is purged by the gas including the oxygen containing gas, it is possible to prevent the emitted light of O2 radical and H2O radical from transmitting the optical filter256a, it is possible to prevent a visual field of the imaging device254afrom being obstructed by the radical emission and to monitor the inside of the furnace with clearer images.

The optical filter256ais an optical filter which does not transmit the radical emission wavelength. However, the optical filter256ais an optical filter which transmits only the light having a wavelength from 700 nm to 1000 nm. Here, “to transmit only a selected wavelength range” may be a characteristic that substantially shields wavelengths other than the selected wavelength range, or may be a characteristic that cannot completely cut off the selected wavelength range and partially transmits the selected wavelength. The optical filter256ais a filter which does not transmit the radical emission wavelength, and thus, even in the case where the inside of the high-temperature furnace filled with the combustible gas is purged by the gas including the oxygen containing gas, it is possible to prevent the light which includes a large amount of light generated by the radical emission and has the wavelength equal to or less than 700 nm from being transmitted to the optical filter256a, and it is possible to prevent the visual field of the imaging device254afrom being obstructed by the radical emission and to monitor the inside of the furnace with clearer images. In addition, it is possible to selectively transmit the light which includes a large amount of light emitted by the gasifier wall111which is an object to be monitored and a particle flow and has the wavelength from 700 nm to 1000 nm, and it is possible to obtain the luminance required for imaging the object to be monitored by the imaging device254awhile shielding the light generated by the radical emission.

In addition, in the present embodiment, in the furnace monitoring device200a, the air supply source220asupplies the air. However, the present invention is not limited to this. The fluid supplied by the air supply source220amay be a gas including the oxygen containing gas.

Moreover, in the present embodiment, in the furnace monitoring device200a, the control means130controls the optical filter switching unit258aso as to attach the optical filter256ato the imaging device254aor so as to detach the optical filter256afrom the imaging device254a. However, the present invention is not limited to this. For example, the optical filter switching unit258amay have a configuration in which the attachment and detachment of the optical filter256aare performed by an operation of an operator.

In addition, in the furnace monitoring device200aof the present embodiment, the optical filter256ais attached to the imaging device254ain the case where the gasifier outlet gas thermometer125exceeds the preset value or in the case where the burner inlet cutoff valves128and129are opened. However, the present invention is not limited to this. A condition for attaching the optical filter256amay be any condition as long as the inside of the gasifier101has the luminance sufficient for imaging in the case where the optical filter256ais attached to the imaging device254a, and for example, a case where an outlet valve of the coal supply unit11is open may be adopted as the condition.

Moreover, the furnace monitoring device200aof the present embodiment is provided in the gasification unit14of the integrated coal gasification combined cycle10. However, the present invention is not limited to this. The furnace monitoring device200acan be applied to any gasification unit as long as the combustible gas containing particles flows through the gasification unit. For example, the gasification unit through which the combustible gas containing particles flows is a gasification unit applied to a garbage incineration plant and a chemical synthesis plant.

Next, a furnace monitoring device200baccording to a second embodiment will be described with reference toFIGS. 4 and 5.FIG. 4is a cross-sectional diagram of the furnace monitoring device according to the second embodiment.FIG. 5is an enlarged diagram showing the furnace monitoring device according to the second embodiment in an enlarged manner. In addition, the furnace monitoring device200bof the second embodiment can be applied to the gasification unit14instead of the furnace monitoring device200aof the above-described first embodiment. That is, the gasification unit of the second embodiment has a configuration similar to that of the gasification unit14except for the furnace monitoring device200b.

The furnace monitoring device200bshown inFIGS. 4 and 5includes a protection tube202b, a fiber pressure resistance tube242b, a fiberscope246b, a monitoring window250b, imaging means252b, a mirror264b, and a cap268b.

The protection tube202bis a cylindrical tube. The protection tube202bincludes an outer cylinder204b, a fluid flow path206b, and an inner cylinder208b. As shown inFIG. 4, the protection tube202bis inserted into a nozzle212b. The nozzle212bis a nozzle which is formed to penetrate the gasifier wall111, the annulus portion115, and the pressure vessel110. The outer cylinder204bis a cylindrical tube. The outer cylinder204bincludes a flange portion214b. The flange portion214bis fixed to the nozzle212b.

The fluid flow path206bis a flow path which is formed between the outer cylinder204band the inner cylinder208band through which cooling water flows. A boss234bis connected to one end of the fluid flow path206band a boss236bis connected to the other end thereof. The boss234bis connected to a cooling water supply system238b. The cooling water supply system238bis a system which is connected to a cooling water cooling device (not shown) and supplies cooled cooling water. Here, for example, the cooling water cooling device is a cooling tower which causes the cooling water and the atmosphere to come into air-liquid contact with each other so as to cool the cooling water. The boss236bis connected to a cooling water recovery system240b. The cooling water recovery system240bis a system which is connected to the cooling water cooling device (not shown) so as to feed the cooling water to the cooling water cooling device (not shown).

The inner cylinder208bis a cylindrical tube. As shown inFIG. 4, a boss216bis formed in the inner cylinder208b. As shown inFIG. 4, the boss216bis connected to a space described later which is surrounded by the fiber pressure resistance tube242b, the transparent window248b, and the inner cylinder208b. The boss216bis connected to an air supply source220bvia an air source valve218b. For example, the air supply source220bis a compressor. The air supply source220bsupplies the air to a space described later surrounded by the fiber pressure resistance tube242band the inner cylinder208bvia the air source valve218band the boss216b, and ejects the air from the monitoring window250bdescribed later to the inside of the gasifier101.

The fiber pressure resistance tube242bis a cylindrical tube. The fiber pressure resistance tube242bincludes a flange portion244band a transparent window248b. As shown inFIG. 4, the flange portion244bis provided in the fiber pressure resistance tube242bon the outside228of the furnace. The flange portion244bis fixed to a flange portion230bof the inner cylinder208b.

The transparent window248bis a window which is formed of a transparent heat resistant member transmitting the light. For example, the transparent heat resistant member transmitting the light is sapphire glass and borosilicate glass. The transparent window248bis attached to the end portion of the fiber pressure resistance tube242bon the inside222of the furnace. In the transparent window248b, an outer periphery of a surface being in contact with the fiber pressure resistance tube242bis sealed.

The fiberscope246bis an industrial endoscope which transmits an image. As shown inFIG. 4, the fiberscope246bis accommodated in the fiber pressure resistance tube242b. The fiberscope246btransmits the light incident from the transparent window248bto an end portion of the fiber pressure resistance tube242bon the outside228of the furnace.

As shown inFIG. 4, the monitoring window250bis an opening which is formed in a portion inserted into the inside of the gasifier101in side surfaces of the protection tube202b.

As shown inFIG. 5, the mirror264bis fixed by a support member266bin a direction in which the light incident from the monitoring window250bis reflected by the fiberscope246b.

The cap268bis a cap which is attached to the end portion of the protection tube202bon the inside222of the furnace. The cap268bis fixed to the protection tube202b. A fluid passage270bthrough which the cooling water flows is formed inside the cap268b. As shown inFIG. 5, in a case where the protection tube202band the cap268bare connected to each other, both end portions of the fluid passage270bare connected to both end portions of the fluid flow path206b, and thus, a connected flow path of the cooling water is formed.

The imaging means252bincludes an imaging device254b, an optical filter256b, an optical filter switching unit258b, a lighting device259b, and an infrared thermometer272b. The imaging device254bis a device which images the inside of the furnace. For example, the imaging device254bis a CCD camera and a CMOS camera. As shown inFIG. 4, the imaging device254bis positioned at which the end portion of the fiberscope246bon the outside228of the furnace and a lens (not shown) of the imaging device254bface each other. The imaging device254bhas a recording function. The imaging device254boutputs an image imaged by an output cable (not shown) to a monitor of a central control room (not shown). The imaging device254bis connected to the control means130.

The optical filter256bis a filter which does not transmit a radical emission wavelength. Specifically, the radical emission wavelength is a wavelength included in the light emitted by radical in a case where a fuel containing carbon is combusted. For example, light emitted by CH radical has a band spectrum around 387 nm and 431 nm, and light emitted by O2 radical has a band spectrum near 759 nm. The optical filter256bis larger than the lens of the imaging device254b. That is, the optical filter256bcan cover the lens of the imaging device254bin a case where the optical filter256bis attached to the imaging device254b. The optical filter256bis fixed to the optical filter switching unit258b.

As shown inFIG. 4, the optical filter switching unit258bis fixed to the flange portion244bof the fiber pressure resistance tube242bon the outside228of the furnace. When the imaging device254bis viewed from the end portion of the fiberscope246bon the outside228of the furnace, the optical filter switching unit258bis an actuator which moves the optical filter256bto a position at which the optical filter256acovers the lens of the imaging device254aor a position at which the optical filter256adoes not overlap the lens of the imaging device254a. For example, the actuator is a servo motor. The optical filter switching unit258ais connected to the control means130.

The lighting device259bis provided in the imaging device254b. For example, the lighting device259ais LED lighting. The lighting device259billuminates the inside of the furnace via the fiberscope246b. In addition, the lighting device259bis provided in the imaging device254b. However, the lighting device259bmay be provided on the end portion of the fiberscope246bon the inside222of the furnace.

The infrared thermometer272bis provided in the imaging device254b. The infrared thermometer272bmeasures a temperature inside the furnace via the fiberscope246b.

Here, an operation of the furnace monitoring device200bof the above-described second embodiment will be described. In the furnace monitoring device200bof the present embodiment, the air supply source220asupplies air to the space surrounded by the protection tube202band the fiber pressure resistance tube242bvia the air source valve218band the boss216bso as to eject the air from the monitoring window250b. The air ejected from the monitoring window250bblows out particles attached to the monitoring window250band the particles filling the inside222of the furnace of the monitoring window. The air ejected from the monitoring window250breacts with the combustible gas filling the inside of the gasifier101and emits light.

The light incident from the monitoring window250bis reflected toward the fiberscope246bby the mirror264b. The light incident on the fiberscope246bis transmitted to the lens of the imaging device254bby the fiberscope246b.

In a case where the gasifier outlet gas thermometer125exceeds a preset value or in a case where the burner inlet cutoff valves128and129are opened, the control means130operates the optical filter switching unit258bto attach the optical filter256bto the imaging device254b. Here, for example, the preset temperature is 1000° C. The optical filter256bshields an inner radical emission wavelength component of the light incident from the inside222of the furnace via the monitoring window250b. That is, the optical filter256bshields the radical emission wavelength component included in the light generated by the reaction between the air elected from the monitoring window250band the combustible gas. The imaging device254bimages light other than the radical emission wavelength transmitting the optical filter256b.

In a case where the gasifier outlet gas thermometer125is equal to or less than a preset value or in a case where the burner inlet cutoff valves128and129are closed, the control means130operates the optical filter switching unit258bto detach the optical filter256bfrom the imaging deli ice254b. Here., for example, the preset temperature is 1000° C.

In the furnace monitoring device200baccording to the second embodiment, the light incident from the monitoring window250bis reflected toward the fiberscope246bby the mirror264b, and the light incident on the fiberscope is transmitted to the lens of the imaging device254bby the fiberscope246b. Accordingly, it is possible to image the inside of the gasifier101from the side wall of the protection tube202b, it is possible to minimize an insertion depth of the protection tube202b, and a fluid friction generated between the gas flow inside the gasifier101and the protection tube202bcan be suppressed so as to be minimized. In addition, it is possible to transmit the light incident on the monitoring window250bfrom the inside of the gasifier101to a location away from the gasifier101such that a disposition position of the imaging device254bcan be separated from the gasifier101, it is possible to prevent the imaging device254bfrom being exposed to a high temperature, and a heat resistant temperature of the imaging device254bcan be lowered.

The furnace monitoring device200bof the second embodiment includes the infrared thermometer272b. Accordingly, it is possible to measure the temperature of the gasifier wall111, and in a gasifier which covers the gasifier wall111with a slag to protect the gasifier wall111from a high heat load, it is possible to detect of a change of the metal temperature of the gasifier wall111, it is possible to detect a change in a thickness of the slag attached to the gasifier wall111, and it is possible to estimate an accumulation rate of thermal fatigue of the gasifier wall111and to determine an inspection time of the gasifier101.

In the furnace monitoring device200baccording to the second embodiment, the imaging device254bhas a recording function. Accordingly, it is possible to check a condition in the furnace in the past and to compare a current furnace condition with a past furnace condition, and in a gasifier which covers the gasifier wall111with a slag to protect the gasifier wall111from a high heat load, it is possible to monitor the change of an attachment condition of the slag, and it is possible to detect an abnormality of the gasifier wall111.

In the furnace monitoring device200baccording to the second embodiment, the fluid flow path206bis formed between the outer cylinder204band the inner cylinder208b, and the cooling water flows through the fluid flow path206b. Accordingly, it is possible to cool the inside of the protection tube202b, it is possible to prevent the temperature of the imaging device254bfrom increasing. and it is possible to protect the furnace monitoring device200bfrom the high heat load of the gasification unit14.

Preferably, a temperature of a purge gas supplied from the air supply source220bis 100° C. or less, and more preferably, the temperature is 50° C. or less. Accordingly, it is more effectively cool the fiberscope246band the imaging means252b.

Preferably, an ejection dynamic pressure in a case where the air supplied by the air supply source220bis ejected from the monitoring window250bis 100 Pa or more. In doing so, it is possible to effectively blow out the particles filling the inside of the gasifier101, and thus, it is possible to secure the field of view of the imaging device254b. In addition, even in a case where the inside of the furnace is in a high particle concentration atmosphere, it is possible to prevent the particles from entering the protection tube202b.

Next, a furnace monitoring device200cof a third embodiment will be described with reference toFIG. 6.FIG. 6is a cross-sectional diagram of the furnace monitoring device according to the third embodiment. In addition, the furnace monitoring device200cof the third embodiment can be applied to the gasification unit14instead of the furnace monitoring device200aof the above-described first embodiment. That is, the gasification unit of the third embodiment has a configuration similar to that of the gasification unit14except for the furnace monitoring device200c. In addition, the furnace monitoring device200cof the third embodiment is similar to the furnace monitoring device200bof the second embodiment except for including an inserting and removing device300c.

The inserting and removing device (movement mechanism)300cincludes a valve302c, a first pipe304c, a second pipe306c, a cylindrical vessel308c, an operation board310c, a first ball screw mechanism320c, a second ball screw mechanism330c, and an electric motor350c.

As shown inFIG. 6, the valve302cis fixed to a portion between the nozzle212cand the first pipe304cby a bolt (not shown) and a nut (not shown). The valve302cis an electric valve in which a motor (not shown) is housed. The valve302cis connected to the operation board310c. In a case where a close operation is input from the operation board310cto the valve302c, the valve302cdrives the motor (not shown) so as to shield a space inside the gasifier101and a space inside the first pipe304c. In a case where an open operation is input from the operation board310cto the valve302c, the valve302cdrives the motor (not shown) to cause a space inside the gasifier101and a space inside the first pipe304cto communicate with each other. In addition, the valve302cis the electric valve. However, the present invention is not limited to this. For example, the valve302cis a solenoid valve or a manual valve.

As shown inFIG. 6, the first pipe304cis fixed to a portion between the valve302cand the second pipe306cusing a bolt (not shown) and a nut (not shown). The first pipe304cincludes a depressurizing device312cand a pressure gauge314c. As shown inFIG. 6, the depressurizing device312cis formed on a side surface of the first pipe304c. The depressurizing device312cis connected to the valve316c. The depressurizing device312copens the valve316cto cause the air in the first pipe304cto flow and decreases the pressure in the first pipe304c. As shown inFIG. 6, the pressure gauge314cis formed on the side surface of the first pipe304c. For example, the pressure gauge314cis a Bourdon tube pressure gauge. The pressure gauge314cmeasures the pressure inside the first pipe304c.

As shown inFIG. 6, the second pipe306cis fixed to a portion between the first pipe304cand the cylindrical vessel308cusing a bolt (not shown) and a nut (not shown). A seal member318cis provided inside the second pipe306c. The seal member318cis a member having a hollow columnar shape. As shown inFIG. 6, a protection tube202cis inserted into a hollow portion of the seal member318c. In a case where the protection tube202cis inserted into the hollow portion, the seal member318cshields the space inside the first pipe304cand a space inside the cylindrical vessel308c.

As shown inFIG. 6, the cylindrical vessel308cis fixed to the second pipe306cusing a bolt (not shown) and a nut (not shown).

The first ball screw mechanism320cincludes a first screw shaft322c, a first nut324c, a first gear326c, and a first support member328c.

As shown inFIG. 6, one end of the first screw shaft322cis rotatably supported by a side surface of the cylindrical vessel308con the inside222of the furnace, and the other end thereof is rotatably supported in a state of penetrating a side surface of the cylindrical vessel303con the outside228of the furnace. The first nut324cis rotatably attached to the first screw shaft322c. The first gear326cis fixed to an end portion of the first screw shaft322con the outside228of the furnace. As shown inFIG. 6, one end of the first support member328cis fixed to the first nut324cand the other end thereof is fixed to the protection tube202c.

The second ball screw mechanism330cincludes a second screw shaft332c, a second nut334c, a second gear336c, and a second support member338c.

As shown inFIG. 6, one end of the second screw shaft332cis rotatably supported by a side surface of the cylindrical vessel308con the inside222of the furnace, and the other end thereof is rotatably supported in a state of penetrating a side surface of the cylindrical vessel308con the outside223of the furnace. The second nut334cis rotatably attached to the second screw shaft332c. The second gear336cis fixed to an end portion of the second screw shaft332con the outside228of the furnace. As shown inFIG. 6, one end of the second support member338cis fixed to the second nut334cand the other end thereof is fixed to the protection tube202c.

A shaft352cis connected to the electric motor350c. As shown inFIG. 6, the shaft352cis rotatably fixed to a side surface of the cylindrical vessel308con the outside228of the furnace. A third gear354cis attached to a tip of the shaft352c. As shown inFIG. 6, the third gear354cis disposed between the first gear326cand the second gear336csuch that these gears mesh with each other. The electric motor350cis connected to the operation board310c. In a case where an operation for inserting the protection tube202cis input from the operation board310cto the electric motor350c, the electric motor350cis rotated in a direction in which the protection tube202cis moved to the inside222of the furnace. In a case where an operation for removing the protection tube202cis input from the operation board310cto the electric motor350c, the electric motor350cis rotated in a direction in which the protection tube202cis moved to the outside228of the furnace.

Here, an operation in a case where the protection tube202cof the furnace monitoring device200cof the above-described third embodiment is removed from the gasifier101. First, an operator operates the operation board310cto rotate the electric motor350c, and thus, the protection tube202cis moved to the outside228of the furnace.

Next, the operator operates the operation board310cso as to close the valve302c. Next, the operator opens the valve316c, and thus, the pressure inside the first pipe304cis decreased by the depressurizing device312c, and the depressurization is performed. Next, the operator confirms that the pressure gauge314cpressure is at atmospheric pressure. Next, the operator opens a manhole (not shown) formed in the cylindrical vessel308cto cool the protection tube202c. After the operator confirms that the protection tube202cis sufficiently cooled, the operator removes the protection tube202cfrom the cylindrical vessel308c.

Next, an operation in a case where the protection tube202cof the furnace monitoring device200cof the above-described third embodiment is inserted into the gasifier101will be described. First, an operator opens the manhole (not shown) formed in the cylindrical vessel308c. Next, the operator attaches the protection tube202cto a portion inside the cylindrical vessel308c. Next., the operator closes the manhole (not shown) formed in the cylindrical vessel308c. Next, the operator operates the operation board310cto rotate the electric motor350c, and thus, the protection tube202cis moved to the inside222of the furnace, and the protection tube202cis inserted in front of the valve302c. Next, the operator operates the operation board310cto open the valve302c. Next, the operator operates the operation board310cto rotate the electric motor350c, and thus, the protection tube202cis moved to the inside222of the furnace, and the protection tube202cis inserted to a predetermined position.

The furnace monitoring device200caccording to the third embodiment includes the inserting and removing device300c. Accordingly, even in a case where trouble occurs in the furnace monitoring device200cduring the operation of the gasification unit14and maintenance is required, it is possible to attach the furnace monitoring device200cto the gasification unit14or to detach the furnace monitoring device200cfrom the gasification unit14without stopping the gasification unit14, and it is possible to improve an operation rate of the gasification unit14.

In addition, the furnace monitoring device200cof the third embodiment includes the first ball screw mechanism320cand the second ball screw mechanism330c. However, the present invention is not limited to this. For example, the number of the ball screw mechanisms may be one or three more.

Hereinbefore, the present invention is described with reference to the above embodiments. However, the technical scope of the present invention is not limited to the scopes described in the above embodiments. Various modifications or improvements can be added to the above-described embodiments within a scope not deviating from the gist of the invention, and an aspect added with the modifications or improvements is also included in the technical scope of the present invention. In addition, the plurality of embodiments may be combined.

For example, the inserting and removing device300cmay be applied to the furnace monitoring device200a.

REFERENCE SIGNS LIST

11: coal supply unit

11a:coal supply line

15: char recovery unit

20: heat recovery steam generator

41: compressed air supply line

42: air separation unit

43: first nitrogen supply line

45: second nitrogen supply line

46: char return line

47: oxygen supply line

48: foreign matter removal unit

49: gas generation line

51: dust collection unit

53: gas discharge line

65: compressed air supply line

66: fuel gas supply line

67: combustion gas supply line

70: flue gas line

71: steam supply line

72: steam recovery line

74: gas purifying unit

111: pressure vessel

121: gas discharge port

125: gasifier outlet gas thermometer

178,129: burner inlet cutoff valve

130: control means

200a,200b,200c:furnace monitoring device

218a:air source valve

220a,220b:air supply source

222: inside of furnace

228: outside of furnace

238b:cooling water supply system

240b:cooling water recovery system

242b:fiber pressure resistance tube

258aoptical filter switching unit

300c:inserting and removing device

320c:first ball screw mechanism

328c:first support member

330c:second ball screw mechanism

338c:second support member