JP2009262016A - Method of separating carbon dioxide and separating apparatus and washing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of separating carbon dioxide capable of separating carbon dioxide from impurities with low energy and easily increasing a carbon dioxide separating speed. <P>SOLUTION: In the method of separating carbon dioxide used in the separating apparatus 200 of the washing apparatus 1, the carbon dioxide is separated from the impurities by giving centrifugal force to the carbon dioxide in a supercritical or pressurized liquid state containing the impurities. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for separating carbon dioxide from impurities, an apparatus for separating carbon dioxide from impurities, and a cleaning apparatus for cleaning an object to be cleaned using carbon dioxide.

  Conventionally, as a cleaning method, there is a wet cleaning method using a solvent such as water, an organic solvent, an acid, or an alkali. However, instead of such a wet cleaning method, a pressurized liquid state or a supercritical state dioxide dioxide is used. A cleaning method using carbon as a solvent is spreading as an environmentally friendly cleaning method. Carbon dioxide in a pressurized liquid state or a supercritical state is applied to cleaning electronic device components such as semiconductor materials that require high-precision cleaning.

  In recent years, a cleaning system using carbon dioxide in a pressurized liquid state or a supercritical state has been applied to clothes cleaning as an object to be cleaned other than a semiconductor. This is because in conventional garment washing, the dry cleaning solvent remains on the object to be washed after washing, which may adversely affect health. Moreover, environmental pollution is caused by the waste solvent after washing.

  In cleaning using carbon dioxide in a pressurized liquid state or supercritical state, carbon dioxide can be vaporized and removed from the object to be cleaned by depressurizing the carbon dioxide after cleaning. Therefore, there is no concern that the cleaning solvent remains on the object to be cleaned. Further, since it is not necessary to dry the object to be cleaned after cleaning, there is an environmental advantage such as not requiring energy for drying.

  In addition, carbon dioxide vaporized by depressurization after washing can be reused as a washing solvent by repressurization. Thus, carbon dioxide can be easily reused with low energy as compared with organic solvents and the like, and the influence on the environment can be suppressed. Further, since carbon dioxide after washing can be repeatedly used as a solvent without being discarded, there is a great advantage from the viewpoint of preventing global warming.

  As described above, the cleaning method using pressurized liquid carbon dioxide or supercritical carbon dioxide as a solvent is an excellent method for reducing the environmental load. It is assumed that it will be reused. Therefore, it is important to increase the efficiency of carbon dioxide recovery and reduce the energy required for recovery.

  Further, it is desirable that the cleaning apparatus circulates carbon dioxide, removes dirt components from the object to be cleaned from carbon dioxide, and always performs cleaning with clean carbon dioxide. From this point, the separation and recovery rate of carbon dioxide is also important.

  Carbon dioxide recovery methods are roughly classified into the following two methods. That is, a gas absorption method and a gas-liquid separation method (distillation).

  The gas absorption method is a method in which separation is performed by dissolving carbon dioxide in an absorbing solution using an alkali absorbing solution having a high solubility of carbon dioxide. In the absorption method, separation can be easily performed by bringing the absorbing solution into contact with carbon dioxide.

The gas-liquid separation method is a method in which carbon dioxide in a pressurized liquid state or supercritical state is depressurized and vaporized to separate from a soil component present in a liquid or solid state at a low pressure (under atmospheric pressure). The gas-liquid separation method is a simple technique that can be separated from the soil components by reducing the pressure and vaporizing carbon dioxide. For example, Japanese Patent Laying-Open No. 2006-281014 (Patent Document 1) describes a cleaning apparatus and a cleaning method for separating carbon dioxide from contaminants by a gas-liquid separation method and circulating the carbon dioxide.
JP 2006-281014 A

  However, the gas absorption method requires a heating / cooling device for separating carbon dioxide from the absorbing solution, which complicates the device. In the case of a cleaning apparatus using carbon dioxide as a solvent, the amount of carbon dioxide to be used is large, and the amount of absorption liquid required is increased accordingly. For this reason, it has the fault that energy required for the heating and cooling for isolate | separating a carbon dioxide from an absorption liquid will become large while an apparatus enlarges.

  In the gas-liquid separation method, in order to increase the separation / recovery rate of carbon dioxide, when the amount of carbon dioxide to be depressurized / vaporized is increased, vaporization is accompanied by a large volume expansion. The flow rate of carbon dioxide increases, and dirt components to be removed accompany the carbon dioxide. In order to prevent entrainment of dirt components, it is necessary to enlarge the apparatus. In addition, when the impurities to be separated are highly viscous substances or solids, a problem of blocking the pipe line also arises.

  Accordingly, an object of the present invention is to provide a carbon dioxide separation method that can separate carbon dioxide from impurities with low energy and can easily increase the separation rate of carbon dioxide. Another object of the present invention is to provide a carbon dioxide separation device that can separate carbon dioxide from impurities at low energy without increasing the size of the device, and can increase the separation rate of carbon dioxide. Is to provide. Furthermore, an object of the present invention is to provide a cleaning device capable of separating carbon dioxide from impurities with low energy without increasing the size of the device, and capable of increasing the separation rate of carbon dioxide. It is.

  The carbon dioxide separation method according to the present invention is characterized in that carbon dioxide is separated from impurities by applying a centrifugal force to carbon dioxide in a supercritical or pressurized liquid state containing the impurities.

  In addition, the carbon dioxide separator according to the present invention includes a centrifugal separator that separates carbon dioxide from impurities by applying centrifugal force to supercritical or pressurized liquid carbon dioxide containing impurities.

  By separating carbon dioxide from impurities using centrifugal force, the flow rate of carbon dioxide can be used as the driving force for separation. Therefore, even when the separation rate of carbon dioxide is increased, there is no need to increase the size of the apparatus for separating carbon dioxide.

  Further, by separating the carbon dioxide using centrifugal force, it is not necessary to decompress the supercritical or pressurized liquid carbon dioxide to a gaseous state. Even if carbon dioxide remains in a supercritical or liquid state, carbon dioxide can be separated from impurities by centrifugal force if there is a difference in density between the impurities and carbon dioxide. Since carbon dioxide is separated from impurities in a supercritical or liquid state, when carbon dioxide is stored or reused as it is, carbon dioxide is separated to be separated from impurities. Not only is the step of vaporizing unnecessary, but the step of liquefying carbon dioxide again is also unnecessary. In this way, the process of vaporizing carbon dioxide from a supercritical or pressurized liquid state and liquefying again after separation and recovery is unnecessary, so that the energy consumed in the separation of carbon dioxide can be reduced.

  By doing in this way, it is possible to separate carbon dioxide from impurities with low energy, and to provide a carbon dioxide separation method and separation apparatus that can easily increase the separation rate of carbon dioxide. it can.

  A cleaning apparatus according to the present invention is a cleaning tank for cleaning an object to be cleaned with carbon dioxide in a supercritical or pressurized liquid state, and applies centrifugal force to carbon dioxide used for cleaning in the cleaning tank. Thus, a centrifuge for separating carbon dioxide from the impurities and a flow path for supplying carbon dioxide separated from the impurities in the centrifuge to the washing tank are provided.

  By separating carbon dioxide from impurities using centrifugal force, the flow rate of carbon dioxide can be used as the driving force for separation. Therefore, it is not necessary to increase the size of the cleaning device even when the carbon dioxide separation rate is increased.

  In addition, by separating carbon dioxide using centrifugal force, it is not necessary to depressurize the supercritical or pressurized liquid carbon dioxide used for cleaning to a gaseous state. Even if carbon dioxide remains in a supercritical or liquid state, carbon dioxide can be separated from impurities by centrifugal force if there is a difference in density between the impurities and carbon dioxide. Since carbon dioxide is separated from impurities in a supercritical or liquid state, it can be separated from impurities when storing the separated carbon dioxide or circulating it again in the washing tank. Not only is the process of vaporizing carbon dioxide unnecessary, but also the process of pressurizing and liquefying carbon dioxide again becomes unnecessary. In this way, the process of vaporizing carbon dioxide from a supercritical or pressurized liquid state and liquefying again after separation and recovery is unnecessary, so that the energy consumed in the cleaning apparatus can be reduced.

  Further, by supplying the carbon dioxide separated from the impurities in the centrifugal separator to the washing tank through the flow path, the carbon dioxide separated from the impurities is allowed to flow without releasing the carbon dioxide to the outside of the washing apparatus. It can be collected in the road and used repeatedly.

  By doing so, it is possible to provide a cleaning device capable of separating carbon dioxide from impurities with low energy without increasing the size of the device and increasing the separation rate of carbon dioxide. it can.

  The cleaning apparatus according to the present invention preferably includes a condensing means for bringing the carbon dioxide separated from the impurities by the centrifugal separating means into a liquid state.

  By doing so, even when carbon dioxide is vaporized in the centrifugal separator after washing, it becomes easy to recover the carbon dioxide by liquefying the carbon dioxide in the condensing means.

  The cleaning device according to the present invention preferably includes a storage container for storing carbon dioxide that has been brought into a liquid state in the condensing means.

  In this way, after the carbon dioxide used for cleaning is condensed, it is stored in a storage container, and if carbon dioxide is required during cleaning, it can be taken out from the storage container and reused. This eliminates the need to supply carbon dioxide from the outside to the cleaning device.

  The cleaning apparatus according to the present invention preferably includes a delivery means for delivering carbon dioxide toward the cleaning tank.

  By doing in this way, the speed | rate which supplies a carbon dioxide to a washing tank can be raised.

  The cleaning device according to the present invention includes a control unit for controlling the pressure and temperature inside the centrifuge unit, a decompression unit for decompressing carbon dioxide inside the centrifuge unit, and an interior of the centrifuge unit. And a temperature control means for adjusting the temperature of carbon dioxide in the control unit, and the control unit controls the decompression means and / or the temperature control means so that the density of carbon dioxide inside the centrifugal separation means becomes a predetermined density. It is preferable that it is comprised.

  By doing so, it becomes possible to adjust the density or phase state of carbon dioxide to be separated in accordance with the density of impurities. By adjusting the density or phase state of carbon dioxide to be separated according to the density of impurities, the energy required for the carbon dioxide liquefaction operation at the subsequent stage of the centrifugal separator can be reduced. In this way, carbon dioxide can be separated and recovered with low energy as the entire cleaning apparatus.

  In addition, by doing so, the density of carbon dioxide can be adjusted in the centrifugal separation means, and therefore, carbon dioxide can be separated from both solid and liquid impurities by centrifugation. By separating carbon dioxide from solid and liquid impurities by centrifugal force and immobilizing it in the centrifugal separation means, piping at the outlet of the centrifugal separation means by solid and liquid impurities deposited by decompression Etc. can be prevented.

  When carbon dioxide is separated from impurities using centrifugal force, volume expansion when carbon dioxide is depressurized can be used as a driving force for separation of impurities. Since the centrifugal separation means separates carbon dioxide and impurities by centrifugal force, the higher the flow rate of carbon dioxide, the higher the impurity separation performance. Therefore, it is not necessary to increase the size of the cleaning device even if the separation and recovery rate of carbon dioxide is increased.

  As described above, according to the present invention, it is possible to separate carbon dioxide from impurities with low energy, and to provide a carbon dioxide separation method capable of easily increasing the separation rate of carbon dioxide. Can do. Further, it is possible to provide a carbon dioxide separation device and a cleaning device capable of separating carbon dioxide from impurities with low energy without increasing the size of the device and capable of increasing the separation rate of carbon dioxide. Can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram schematically showing an entire cleaning apparatus as one embodiment of the present invention.

  As shown in FIG. 1, the cleaning apparatus 1 includes a cleaning tank 100 for storing an object to be cleaned 20, a separation apparatus 200 including a cyclone (centrifugation apparatus) 201 as a centrifugal separation means, and a condensing unit as a condensation means. 300, a liquefied carbon dioxide tank 400 as a storage container for storing carbon dioxide 10, a pump 500 as a delivery means, a pressure reducing valve 600 as a pressure reducing means, a temperature regulator 700 as a temperature adjusting means, and a control unit. A liquefied carbon dioxide tank 400 is provided with a temperature regulator 410 for adjusting the temperature inside the liquefied carbon dioxide tank 400. The cleaning tank 100, the pressure reducing valve 600, the cyclone 201, the condensing unit 300, the liquefied carbon dioxide tank 400, the pump 500, and the cleaning tank 100 are sequentially connected by a flow path. The temperature controller 700 is disposed on the outer peripheral surface of the cyclone 201. The separation device 200 includes a cyclone 201, a temperature controller 700, a dirty component disposal flow path 220, a valve 221, and a flow path 210 having a valve 211.

  In the cleaning tank 100, for example, a fiber structure such as clothing is accommodated as the object 20 to be cleaned. The target object 20 to be cleaned by the cleaning apparatus 1 is not limited to a fiber structure as long as it is cleaned with supercritical or pressurized liquid carbon dioxide. A temperature controller 110 is disposed in the cleaning tank 100. The temperature controller 110 adjusts the temperature inside the cleaning tank 100. A carbon dioxide purge flow path 120 having a valve 121 and a flow path 130 are connected to the cleaning tank 100. The cleaning tank 100 is connected to the cyclone 201 via the flow path 130, the pressure reducing valve 600, and the flow path 610.

  At the bottom of the cyclone 201, a dirty component disposal flow path 220 having a valve 221 is connected. A flow path 210 having a valve 211 is connected to the upper part of the cyclone 201. The cyclone 201 is connected to the condensing unit 300 via the flow path 210.

  The condensing unit 300 includes a compressor 310, a cooler 320, a valve 330, and a cooler outlet channel 331. The compressor 310 is connected to the cyclone 201 by a flow path 210 including a valve 211. The compressor 310 is connected to the cooler 320 by a flow path 311. The cooler 320 is connected to the liquefied carbon dioxide tank 400 by a cooler outlet channel 331 having a valve 330.

  The liquefied carbon dioxide tank 400 is connected to the pump 500 by a flow path 420 including a valve 421. The pump 500 is connected to the cleaning tank 100 by a flow path 510.

  FIG. 2 is a diagram schematically showing the inside of the cyclone of the cleaning apparatus and the periphery of the cyclone.

  As shown in FIG. 2, the cyclone 201 has a substantially conical shape formed so that the diameter is large at the upper part and the diameter gradually decreases toward the lower part. A temperature controller 700 is disposed on the outer peripheral surface of the cyclone 201. A flow path 610 having a pressure reducing valve 600 is connected to the upper part of the cyclone 201. The channel 610 is connected so that carbon dioxide flowing through the channel 610 flows along the tangential direction of the peripheral wall surface of the conical cyclone 201. The carbon dioxide that has flowed into the cyclone 201 from the flow path 610 becomes a swirl flow that swirls inside the cyclone 201 as indicated by a two-dot chain line in the figure. At this time, carbon dioxide and impurities are separated by the centrifugal force generated by the swirling flow and the density difference between carbon dioxide and impurities.

  FIG. 3 is a block diagram showing a control-related configuration of the cleaning apparatus.

  As shown in FIG. 3, the control unit 800 transmits a control signal to the pressure reducing valve 600 and the temperature regulator 700. The control unit 800 controls at least one of the pressure reducing valve 600 and the temperature controller 700 so that the density of carbon dioxide inside the cyclone 201 (FIGS. 1 and 2) becomes a predetermined density. When the pressure reducing valve 600 is opened and closed based on the control signal transmitted from the control unit 800, the pressure inside the cyclone 201 is adjusted. Further, when the temperature controller 700 is driven based on the control signal transmitted from the control unit 800, the temperature inside the cyclone 201 is adjusted.

  Hereinafter, the operation of the cleaning apparatus 1 will be described with reference to FIGS. 1 to 3.

  After the user accommodates the object 20 to be cleaned in the cleaning tank 100, the valve 421 is opened, the pump 500 is driven, and the pressurized carbon dioxide 10 in the liquid state is supplied to the cleaning tank 100. . The carbon dioxide 10 in the liquid state may be further pressurized by the pump 500 and supplied to the cleaning tank 100 as carbon dioxide in the supercritical state. Inside the cleaning tank 100, the object 20 to be cleaned is cleaned with the carbon dioxide 10 in a supercritical or liquid state. The inside of the cleaning tank 100 is set so that the pressure is p1 and the temperature is T1. Under the conditions of the pressure p1 and the temperature T1, the carbon dioxide 10 exists as a liquid state or a supercritical state.

  At this time, the valve 121 of the carbon dioxide purge flow path 120 is closed. On the other hand, the decompression valve 600 is set so that the carbon dioxide 10 passing through the decompression valve 600 is decompressed to a predetermined pressure p2. The pressure p2 is a pressure smaller than the pressure p1. A valve 211 of the flow path 210 connecting the cyclone 201 and the compressor 310 is opened.

  The carbon dioxide 10 used for cleaning removes dirt components as impurities from the object 20 to be cleaned. Impurities are dissolved or mixed in the carbon dioxide 10. The carbon dioxide 10 containing impurities is depressurized to a pressure p 2 from the cleaning tank 100 through the pressure reducing valve 600 and supplied to the cyclone 201.

  The pressure p2 inside the cyclone 201 is set to a pressure lower than the pressure p2 inside the cleaning tank 100. Therefore, the carbon dioxide 10 flows from the cleaning tank 100 into the cyclone 201 due to a pressure difference between the inside of the cyclone 201 and the inside of the cleaning tank 100. The carbon dioxide 10 flows from the upper part of the cyclone 201 into the cyclone 201 so as to flow along the circumferential tangential direction of the circumferential wall surface of the cyclone 201 through the flow path 610. The carbon dioxide 10 flows downward in the cyclone 201 while turning along the shape of the peripheral wall surface of the cyclone 201. At the bottom of the cyclone 201, the carbon dioxide 10 flows into the flow path 210 connected to the cyclone 201. The carbon dioxide 10 that has flowed into the flow path 210 flows toward the condensing unit 300.

  In this way, a swirling flow of carbon dioxide 10 is generated in the cyclone 201, and the carbon dioxide 10 and impurities are centrifuged. The control unit 800 controls the temperature regulator 700 so that the temperature of the carbon dioxide 10 becomes T2. The temperature T2 is set to a temperature at which the density of the carbon dioxide 10 at the pressure p2 becomes a predetermined density ρ. The predetermined density ρ is a density different from the density of impurities removed from the carbon dioxide 10. Therefore, there is a difference between the carbon dioxide 10 and the impurity density under the conditions of the pressure p2 and the temperature T2.

  In order to carry out separation by centrifugal force, there must be a difference in the density of carbon dioxide and the impurities that are soil components. Conversely, separation is possible if there is a density difference. Therefore, in the separation by centrifugal force, it is not necessary to reduce the pressure to a pressure at which carbon dioxide is completely vaporized in order to cause the soil components to phase-separate in a liquid or solid state as in the conventional method. In the cleaning apparatus 1 that separates carbon dioxide and impurities by centrifugal force, the pressure at which the density difference between carbon dioxide and impurities occurs, for example, the pressure at which carbon dioxide and dirt components separate into liquid-liquid phases, and the pressure at which liquid-solid phases separate. Even if the pressure reduction is maintained, impurities and carbon dioxide can be separated by centrifugal force if a density difference occurs. In this way, carbon dioxide can be separated and recovered even in a liquid state. Therefore, carbon dioxide in a supercritical or liquid state is once converted into a gaseous state and used for cleaning. It is no longer necessary to compress, cool and liquefy from the gaseous state, and the entire cleaning apparatus 1 can be recovered with low energy.

  In the conventional gas-liquid separation method, when the amount of carbon dioxide to be vaporized is increased, the flow velocity in the gas-liquid separation means is correspondingly increased, and dirt components are accompanied by carbon dioxide exiting from the gas-liquid separation means. End up. Therefore, in order to increase the separation and recovery rate of carbon dioxide, it is necessary to increase the volume of the gas-liquid separation means. However, in the cleaning apparatus 1, since the separation of carbon dioxide and impurities is performed by centrifugal force, increasing the flow rate is advantageous because the centrifugal force increases and the separation performance increases. Therefore, in the cleaning apparatus 1, even if the amount of carbon dioxide increases, the separation and recovery rate of carbon dioxide can be increased without increasing the volume of the apparatus, and the contamination component with carbon dioxide can be prevented. it can.

  Impurities separated from the carbon dioxide 10 are discarded in the dirty component disposal flow path 220 connected to the lower part of the cyclone 201. The carbon dioxide 10 from which impurities have been removed passes upward through the central portion of the cyclone 201 and flows out into the flow path 210 as indicated by a two-dot chain line in FIG. As described above, the impurities removed from the carbon dioxide 10 are fixed to the dirty component disposal flow path 220 of the separation device 200 and do not flow into the flow path 210.

  The carbon dioxide 10 separated from the impurities flows into the condensing unit 300 through the flow path 210 including the valve 211. In the condensing unit 300, first, clean carbon dioxide 10 from which dirt has been separated is compressed by the compressor 310 to a pressure p3. The pressure p3 is set to be higher than the saturated vapor pressure at the temperature Tc that can be cooled by the cooler 320. The clean carbon dioxide 10 compressed to the pressure p3 is then cooled to the temperature Tc by the cooler 320. The cooled carbon dioxide 10 becomes liquid in the cooler outlet channel 331 and is supplied to the liquefied carbon dioxide tank 400. The carbon dioxide 10 supplied to the liquefied carbon dioxide tank 400 is supplied to the cleaning tank 100 by the pump 500. The carbon dioxide 10 circulates in the cleaning apparatus 1 by such a cycle. The cleaning apparatus 1 operates this cycle continuously.

  As described above, the carbon dioxide separation method used in the separation device 200 of the cleaning device 1 is configured to remove carbon dioxide from impurities by applying centrifugal force to supercritical or pressurized liquid carbon dioxide containing impurities. It is characterized by separating.

  The carbon dioxide separator 200 includes a cyclone 201 that separates carbon dioxide from impurities by applying centrifugal force to the supercritical or pressurized liquid carbon dioxide containing the impurities.

  By separating carbon dioxide from impurities using centrifugal force, the flow rate of carbon dioxide can be used as the driving force for separation. Therefore, even if the separation rate of carbon dioxide is increased, it is not necessary to enlarge the cyclone 201 for separating carbon dioxide.

  Further, by separating carbon dioxide using centrifugal force, it is not necessary to depressurize the supercritical or pressurized liquid carbon dioxide to a gaseous state. Even if carbon dioxide remains in a supercritical or liquid state, carbon dioxide can be separated from impurities by centrifugal force if there is a difference in density between the impurities and carbon dioxide. Since carbon dioxide is separated from impurities in a supercritical or liquid state, when carbon dioxide is stored or reused as it is, carbon dioxide is separated to be separated from impurities. A vaporizing step is unnecessary, and a step of liquefying carbon dioxide again is unnecessary. In this way, the process of vaporizing carbon dioxide from a supercritical or pressurized liquid state and liquefying again after separation and recovery is unnecessary, so that the energy consumed in the separation of carbon dioxide can be reduced.

  In this way, it is possible to separate carbon dioxide from impurities with low energy, and to provide a carbon dioxide separation method and separation device 200 that can easily increase the separation rate of carbon dioxide. Can do.

  Further, the cleaning apparatus 1 includes a cleaning tank 100 for cleaning the object 20 to be cleaned with carbon dioxide in a supercritical or pressurized liquid state, and a centrifugal force applied to the carbon dioxide used for cleaning in the cleaning tank 100. A cyclone 201 for separating impurities by being provided, and a flow path for supplying carbon dioxide separated from the impurities in the cyclone 201 to the cleaning tank 100 are provided.

  By separating carbon dioxide from impurities using centrifugal force, the flow rate of carbon dioxide can be used as the driving force for separation. Therefore, it is not necessary to increase the size of the cleaning device 1 even when the separation rate of carbon dioxide is increased.

  In addition, by separating carbon dioxide using centrifugal force, it is not necessary to depressurize the supercritical or pressurized liquid carbon dioxide used for cleaning to a gaseous state. Even if carbon dioxide remains in a supercritical or liquid state, carbon dioxide can be separated from impurities by centrifugal force if there is a difference in density between the impurities and carbon dioxide. Since carbon dioxide is separated from impurities in a supercritical or liquid state, the carbon dioxide after separation is stored, or when it is circulated again to the washing tank 100 as it is, it is separated from impurities. In addition, the step of vaporizing carbon dioxide is unnecessary, and the step of liquefying carbon dioxide again is unnecessary. In this way, the process of vaporizing carbon dioxide from a supercritical or pressurized liquid state and liquefying again after separation and recovery is unnecessary, so that the energy consumed in the cleaning apparatus 1 can be reduced.

  Further, by supplying the carbon dioxide separated from the impurities in the cyclone 201 to the cleaning tank 100 through the flow path, the carbon dioxide separated from the impurities can be released without releasing the carbon dioxide to the outside of the cleaning device 1. It can be recovered in the flow path and used repeatedly.

  Thus, it is possible to provide a cleaning device 1 that can separate carbon dioxide from impurities with low energy without increasing the size of the device, and can increase the separation rate of carbon dioxide. Can do.

  Moreover, the cleaning apparatus 1 includes a condensing unit 300 for bringing carbon dioxide separated from impurities by the cyclone 201 into a liquid state.

  By doing so, even when carbon dioxide is vaporized in the cyclone 201 after cleaning, it becomes easy to recover the carbon dioxide by liquefying the carbon dioxide in the condensing unit 300.

  The cleaning apparatus 1 also includes a liquefied carbon dioxide tank 400 for storing carbon dioxide that has been brought into a liquid state in the condensing unit 300.

  In this way, after the carbon dioxide used for cleaning is condensed, it is accommodated in the liquefied carbon dioxide tank 400, and if carbon dioxide is required during cleaning, it is taken out from the liquefied carbon dioxide tank 400. Since it can be reused, it is not necessary to supply carbon dioxide to the cleaning apparatus 1 from the outside.

  Further, the cleaning apparatus 1 includes a pump 500 for sending carbon dioxide toward the cleaning tank 100.

  By doing in this way, the speed | rate which supplies a carbon dioxide to the washing tank 100 can be raised.

  The cleaning apparatus 1 also includes a control unit 800 for controlling the pressure and temperature inside the cyclone 201, a pressure reducing valve 600 for depressurizing carbon dioxide inside the cyclone 201, and carbon dioxide inside the cyclone 201. The controller 800 controls the pressure reducing valve 600 and / or the temperature controller 700 so that the density of carbon dioxide in the cyclone 201 becomes a predetermined density. Is configured to do.

  By doing so, it becomes possible to adjust the density or phase state of carbon dioxide to be separated in accordance with the density of impurities. By adjusting the density or phase state of carbon dioxide to be separated according to the density of impurities, the energy required for the carbon dioxide liquefaction operation at the subsequent stage of the cyclone 201 can be reduced. In this way, carbon dioxide can be separated and recovered with low energy as the entire cleaning apparatus 1.

  Moreover, since the density of carbon dioxide can be adjusted in the cyclone 201 by doing in this way, it is possible to separate carbon dioxide from both solid and liquid impurities by centrifugation. The carbon dioxide is separated from the solid and liquid impurities by centrifugal force, and is fixed in the cyclone 201, so that the solid and liquid impurities deposited by the reduced pressure, such as piping at the outlet of the cyclone 201 Blockage can be prevented.

  When carbon dioxide is separated from impurities using centrifugal force, volume expansion when carbon dioxide is depressurized can be used as a driving force for separation of impurities. Since the cyclone 201 separates carbon dioxide and impurities by centrifugal force, the higher the flow rate of carbon dioxide, the higher the impurity separation performance. Therefore, it is not necessary to increase the size of the cleaning device 1 even if the carbon dioxide separation and recovery rate is increased.

  As described above, if there is a difference in density between carbon dioxide as a solvent and a substance to be separated, carbon dioxide can be separated from impurities. The carbon dioxide separation method in the cleaning apparatus 1 according to the present invention can be used, for example, in a separation process of a substance extraction technique that applies a supercritical state of carbon dioxide. For example, after vitamin E extraction from soybean, dioxin extraction in soil, and additive extraction in a polymer, vitamin E, dioxin and additives are separated from carbon dioxide by the carbon dioxide separation method of the present invention. be able to. In particular, separation is effective when the substance to be separated is precipitated from the dissolved state by adjusting the phase state of carbon dioxide.

  FIG. 4 is a diagram schematically showing the entire cleaning apparatus as another embodiment of the present invention.

  As shown in FIG. 4, the cleaning device 2 is different from the cleaning device 1 shown in FIG. 1 in that the liquefied carbon dioxide tank 400 is directly connected to the cleaning tank 100 by a flow path 420 having a valve 421. The cleaning tank 100 is connected to the pump 500 by a flow path 130. The pump 500 is connected to the pressure reducing valve 600 by a flow path 510. Other configurations of the cleaning device 2 are the same as those of the cleaning device 1.

  Thus, in the cleaning apparatus 2, the pump 500 is disposed on the downstream side of the cleaning tank 100 in the flow of carbon dioxide. Even in the cleaning apparatus 2 having such a configuration, when the pump 500 is driven, the supercritical or liquid carbon dioxide 10 is sent from the liquefied carbon dioxide tank 400 into the cleaning tank 100.

  Other configurations and effects of the cleaning device 2 are the same as those of the cleaning device 1.

  The embodiment disclosed above should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above embodiment but by the scope of claims, and includes all modifications and variations within the meaning and scope equivalent to the scope of claims.

  The carbon dioxide separation method according to the present invention can be used in a separation step of a material extraction technique that applies the supercritical state of carbon dioxide. For example, after vitamin E extraction from soybean, dioxin extraction in soil, and additive extraction in polymer, vitamin E, dioxin and additives are separated from carbon dioxide by the carbon dioxide separation method of the present invention. be able to. In particular, separation is effective when the substance to be separated is precipitated from the dissolved state by adjusting the phase state of carbon dioxide.

1 is a diagram schematically showing an entire cleaning apparatus as one embodiment of the present invention. FIG. It is a figure which shows typically the inside of the cyclone of a washing | cleaning apparatus, and the periphery of a cyclone. It is a block diagram which shows the control relevant structure of a washing | cleaning apparatus. As another embodiment of the present invention, it is a diagram schematically showing an entire cleaning apparatus.

Explanation of symbols

  1, 2: Cleaning device 10: Carbon dioxide, 20: Object to be cleaned, 100: Cleaning tank, 200: Separation device, 201: Cyclone, 300: Condensing unit, 400: Liquefied carbon dioxide tank, 500: Pump, 600: Pressure reducing valve, 700: temperature controller, 800: control unit.

Claims (7)

  A method for separating carbon dioxide, comprising: separating carbon dioxide from impurities by applying centrifugal force to carbon dioxide in a supercritical or pressurized liquid state containing the impurities.   A carbon dioxide separator comprising a centrifugal separator that separates carbon dioxide from impurities by applying centrifugal force to carbon dioxide in a supercritical or pressurized liquid state containing the impurities. A cleaning tank for cleaning the object to be cleaned with supercritical or pressurized liquid carbon dioxide;
Centrifuge means for separating carbon dioxide from impurities by applying centrifugal force to carbon dioxide used for washing in the washing tank;
A cleaning apparatus comprising: a flow path for supplying carbon dioxide separated from impurities in the centrifugal separator to the cleaning tank.   The cleaning apparatus according to claim 3, further comprising a condensing unit for bringing carbon dioxide separated from impurities by the centrifugal separation unit into a liquid state.   The cleaning apparatus according to claim 4, further comprising a storage container for storing carbon dioxide that has been brought into a liquid state in the condensing means.   The cleaning apparatus according to any one of claims 3 to 5, further comprising a sending unit for sending carbon dioxide toward the washing tank. A control unit for controlling the pressure and temperature inside the centrifuge,
Decompression means for decompressing carbon dioxide inside the centrifugation means;
A temperature adjusting means for adjusting the temperature of carbon dioxide inside the centrifugal separation means,
The control unit is configured to control the pressure reducing unit and / or the temperature adjusting unit so that a density of carbon dioxide inside the centrifugal separating unit becomes a predetermined density. Item 7. The cleaning device according to any one of Items 6 to 6.

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