JP2007014919A - Exhaust gas treatment device and exhaust gas treatment system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize an exhaust gas treatment device and its system for treating an exhaust gas containing an organic solvent. <P>SOLUTION: An organic solvent gas is introduced in an exhaust gas treatment device 1, and the organic solvent gas contained in the exhaust gas is removed and discharged in the atmosphere. The organic solvent gas of low concentration and the organic solvent gas of high concentration introduced in the exhaust gas treatment device 1 are introduced in a low-concentration gas treatment means 2 and a high-concentration gas treatment means 3, respectively, and removed. The exhaust gas treatment device 1 comprises the low-concentration gas treatment means 2 and the high-concentration gas treatment means 3, and only one exhaust gas treatment device can cope with both the low-concentration organic solvent gas and the high-concentration organic solvent gas, and the gas of two kinds of concentration can be simultaneously treated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an exhaust gas purification apparatus that removes harmful substances such as organic solvents contained in exhaust gas. In particular, the present invention relates to an apparatus and system for suppressing the generation of exhaust gas from a source that emits exhaust gas containing a volatile organic compound (VOC) that is a cause of air pollution, and removing and recovering VOC from the generated exhaust gas.

  Conventionally, this type of gas processing device has a method of processing by the end-of-pipe of a local exhaust device installed at the generation source and a method of suppressing generation from the generation source by suctioning and processing from the vicinity of the generation source or inside the generation source. There is.

  In the former method, ambient air is simultaneously sucked in by local exhaust, so it is necessary to process a relatively low concentration of exhaust gas. Adsorption / concentration with an adsorbent such as activated carbon and zeolite, and a method of processing the gas after concentration Often used. Treatment methods include liquefaction recovery by cooling condensation and decomposition by combustion / catalytic combustion.

  Moreover, since the latter system can process a high-concentration gas because it is sucked from the vicinity of the generation source or from the generation source, it can be processed without requiring concentration.

  In the former system, the organic solvent gas is adsorbed with an adsorbent such as activated carbon or zeolite, and the gas that does not contain organic solvent after adsorption is released to the atmosphere. It is known that the desorbed and regenerated material is cooled and the concentrated gas of the desorbed organic solvent is cooled, liquefied and recovered.

(For example, Patent Document 1)
Hereinafter, the exhaust gas treatment apparatus will be described with reference to FIG.

  As shown in the figure, a conventional exhaust gas treatment apparatus 101 comprises an adsorbing means 102 for adsorbing an organic solvent gas, a desorbing means 103 for desorbing the adsorbed organic solvent gas, and a liquefying means 104 for liquefying the desorbed organic solvent gas. ing. The adsorbing means 102 includes an adsorbent such as activated carbon or zeolite, and adsorbs and removes the organic solvent in the exhaust gas. When the adsorbent is saturated, the organic solvent is desorbed by the desorption means 103 to regenerate the adsorbent. Here, the desorption means 103 uses a vacuum pump and desorbs the organic solvent by reducing the pressure.

  The desorbed organic solvent gas is sent to the liquefying means 104, cooled and liquefied. The uncondensed gas that has passed through the liquefying means 104 is exhausted as it is or returned to the adsorbent again.

  The latter type of equipment is known to cool the organic solvent gas and reduce the saturated vapor pressure to condense the organic solvent, as well as to compress the gas and increase the partial pressure of the organic solvent to condense, liquefy and recover. ing. In order to easily condense, the concentration of the organic solvent gas is increased in advance by a concentrating device and introduced into the gas recovery device.

(For example, Patent Document 2)
Hereinafter, the recovery apparatus will be described with reference to FIG.

As shown in the figure, the organic solvent gas is pressurized and introduced into the capacitor tank 106 by a vacuum pump as the suction and pressurizing means 105. The condenser tank 106 is cooled by the refrigerant from the heat pump 108. The organic solvent gas introduced into the capacitor tank 106 is condensed and liquefied by the effects of pressurization and cooling. The liquefied organic solvent is recovered in the organic solvent recovery tank 107. The gas after organic solvent recovery is discharged from the capacitor tank 106.
Japanese Patent Laid-Open No. 11-71584 JP 2003-71239 A

  In such an exhaust gas treatment device, the amount of adsorbent used is reduced, the treatment means such as liquefaction and combustion are miniaturized, the device is miniaturized, and the organic solvent gas in the exhaust gas is reliably removed. It is requested.

  However, in the case of the conventional exhaust gas treatment device installed in the end-of-pipe of the local exhaust device, a large amount of adsorbent for adsorption concentration is required in order to cope with the air volume of the local exhaust device, and the device has been enlarged. .

  In addition, when processing by sucking from the vicinity of the source or inside the source, the device can be downsized because it can process high-concentration gas, but it cannot completely prevent discharge from the source. In some cases, a local exhaust device and an exhaust gas treatment device at its end-of-pipe are required, and high-concentration gas and low-concentration gas exhaust gas treatment devices are necessary.

  Further, since the exhaust gas from the local exhaust device is diluted with a large amount of air, it has a relatively low concentration, for example, 1000 ppm or less. Further, the gas sucked directly from the vicinity of the generation source or directly from the generation source has a relatively high concentration, for example,% order. When processing such gases having greatly different concentrations, it is necessary to install an exhaust gas treatment apparatus suitable for each.

  The present invention solves such a conventional problem, and a single exhaust gas treatment device treats the gas in the vicinity of the source or within the source and the exhaust gas of the local exhaust device, thereby generating the source. The purpose is to reduce gas emissions from the air, reduce the air volume of the local exhaust device, supply a small exhaust gas treatment device, and reliably remove organic solvent gas in the exhaust gas to prevent atmospheric emission .

  In addition, in a cleaning tank and exhaust gas treatment system that treats exhaust gas using a cleaning tank using a solvent as a source, treatment of gas in the vicinity of the source or within the source and the local exhaust Reduces the amount of organic solvent gas generated by treating exhaust gas and optimizing the operating conditions of the cleaning tank, supplying a small and low-priced exhaust gas treatment device, and ensuring that organic solvent gas is contained in the exhaust gas. Its purpose is to remove it and prevent atmospheric emission.

  In order to achieve the above object, the exhaust gas treatment apparatus of the present invention comprises a low-concentration gas treatment means for treating an organic solvent gas of exhaust gas exhausted by a local exhaust device installed in a generation source of an organic solvent, and the organic solvent of the generation source The exhaust gas treatment device comprises high-concentration gas treatment means for directly treating gas, and can individually introduce exhaust gas.

  By this means, two kinds of gas treatment of high concentration gas and low concentration gas can be performed with one device, and the organic solvent gas of the source is processed by the high concentration gas processing means, so the air volume of the local exhaust device is reduced. Therefore, the low-concentration gas processing means can be downsized.

  The other means is a low-concentration gas treatment means that adsorbs the organic solvent gas in the exhaust gas and releases the gas after removing the organic solvent gas to the atmosphere, and desorbs the organic solvent gas adsorbed on the adsorption means. And desorbing and concentrating means to be concentrated and introduced into the high-concentration gas processing means, and an organic solvent provided as a high-concentration gas processing means and a liquefying means for cooling the organic solvent gas concentrated by the desorption and concentrating means into a liquid In the gas recovery apparatus, a high concentration gas introducing means for directly introducing a high concentration organic solvent gas into the liquefying means is provided.

  By this means, the organic solvent gas processed by the low concentration gas processing means and the concentrated organic solvent gas and the source organic solvent gas are introduced into the high concentration gas processing means, thereby processing the gas with a single high concentration gas processing means. In addition, by liquefying the organic solvent gas using the high-concentration gas processing means as the liquefying means, the organic solvent gas can be recovered and reused with a small apparatus.

  The other means is a flow rate adjusting means for measuring the organic solvent gas concentration of the exhaust gas of the local exhaust device to be introduced into the low concentration gas processing means and adjusting the flow rate of the high concentration gas introducing means according to the organic solvent gas concentration. It is equipped with.

  By this means, the concentration of the organic solvent in the exhaust gas of the local exhaust device is measured, and by adjusting the processing amount of the high concentration gas processing means according to the concentration, the gas concentration of the local exhaust device becomes thicker and the low concentration gas processing means Therefore, even if the exhaust gas treatment device is downsized, the exhaust gas treatment can be reliably performed.

  Another means is to introduce a part of the high concentration gas introduced by the high concentration gas introduction means into the adsorption means so as to increase the concentration of the organic solvent in the adsorption means.

  By this means, the concentration of the concentrated gas can be increased and the variation in concentration can be reduced, so that the capability of the high concentration gas processing means can be stabilized, and a small exhaust gas processing apparatus can be provided. Become.

  Another means is to adjust the amount of high-concentration gas introduced into the adsorbing means so as to optimize the organic solvent concentration in the adsorbing means.

  By this means, it is possible to prevent breakthrough of the adsorbing means due to the introduction of high concentration gas and to further stabilize the concentration of the concentrated gas, so that a small exhaust gas treatment apparatus capable of reliably treating organic solvent gas is provided. Is possible.

  Further, the other means introduces the cleaning tank for storing the organic solvent, the local exhaust apparatus for exhausting the organic solvent gas generated from the cleaning tank as exhaust gas, and the exhaust gas of the local exhaust apparatus to the low concentration gas processing means, The high-concentration organic solvent gas in the cleaning tank is introduced into the high-concentration gas processing means by the high-concentration gas introduction means.

  By this means, it is possible to provide an exhaust gas treatment system that can reduce the discharge of the organic solvent from the cleaning tank.

  Further, the other means heats the organic solvent stored by the heating means installed in the cleaning tank to generate the vapor of the organic solvent, cools the vapor by the cooling means installed on the inner wall of the cleaning tank, and In the cleaning apparatus for storing the object to be cleaned in an organic solvent and cleaning it with steam, and in the exhaust gas processing for processing the organic solvent gas discharged from the cleaning apparatus, the steam in the cleaning tank is stored. The gas above the position, that is, above the vapor line, is introduced into the high concentration gas processing means by the high concentration gas introduction means.

  By this means, since the organic solvent gas discharged from the cleaning tank can be reduced, the air volume of the local exhaust device can be reduced, and a system using a small exhaust gas treatment device can be provided.

  Another means is an exhaust gas treatment system that introduces the gas below the vapor line into the high concentration gas treatment means by the high concentration gas introduction means.

  By this means, an organic solvent gas having a concentration close to 100% can be introduced into the high-concentration gas processing means, so that it is possible to provide an exhaust gas treatment system that can reduce the capacity of the high-concentration gas processing means.

  Another means measures the concentration of the low-concentration gas and controls the heating means and cooling means of the cleaning tank.

  By this means, it is possible to provide an exhaust gas treatment system capable of suppressing the generation of exhaust gas exceeding the capacity of the exhaust gas treatment device by controlling the heating means and cooling means of the cleaning tank.

  Further, the other means includes an atmospheric temperature measuring means for measuring the atmospheric temperature in which the cleaning tank is installed, and controls the heating means and the cooling means from the concentration of the low concentration gas and the atmospheric temperature measured by the atmospheric temperature measuring means. Is.

  By this means, by adding the atmospheric temperature to the control of the heating means and the cooling means, it is possible to provide an exhaust gas treatment system that enables more stable operation of the cleaning tank.

  In addition, the other means is provided with level detecting means for detecting the position of the vapor line, and the flow rate of the high concentration gas introducing means is adjusted by the flow rate adjusting means in accordance with a signal from the level detecting means.

  Since the position of the vapor line can be stabilized by this means, it is possible to provide an exhaust gas treatment system that can reduce and stabilize the amount of organic solvent gas discharged from the cleaning tank.

  Another means is characterized in that the flow rate of the high-concentration gas introducing means is adjusted by the flow rate adjusting means according to the signal from the level detecting means, and at the same time, the heating means and the cooling means of the cleaning tank are controlled.

  By this means, in addition to the flow rate of the high-concentration gas introduction means for controlling the position of the vapor line, the heating means and cooling means of the cleaning tank are controlled to provide an exhaust gas treatment system that can stabilize the position of the vapor line more reliably. can do.

  The other means includes an alarm output means for outputting an alarm when the vapor line position detected by the level detection means rises.

  By this means, it is possible to provide an exhaust gas treatment system that can know the abnormality of the cleaning tank.

  Further, the other means is characterized in that the suction port is moved in accordance with the position of the vapor line detected by the level detection means.

  By this means, it is possible to provide an exhaust gas treatment system capable of always sucking gas from the same position with respect to the vapor line even when the position of the vapor line is moved.

  The other means is characterized in that at least one of the suction amount of the high concentration gas introducing means, the heating means of the cleaning tank, and the cooling means is controlled so that the position of the vapor line does not change.

  By this means, the position of the vapor line can be stabilized, so that it is possible to provide an exhaust gas treatment system in which the exhaust gas concentration is stabilized and the fluctuation of the concentration of the gas introduced into the exhaust gas treatment device is reduced.

  According to the present invention, an exhaust gas treatment having an effect of simultaneously treating exhaust gas from a local exhaust device, that is, exhaust gas having a relatively low concentration and exhaust gas from a source, that is, exhaust gas having a relatively high concentration, with one exhaust gas treatment device. Equipment can be provided.

  In addition, by processing the gas directly from the generation source, it is possible to suppress the generation from the generation source, so the air volume of the local exhaust can be reduced and energy saving is achieved, and the air volume of the local exhaust device is reduced, so the exhaust gas processing device is reduced in size. It is possible to provide an exhaust gas treatment apparatus having an effect of being able to be made.

  Further, by stabilizing the gas concentration introduced into the high concentration gas processing means, it is possible to provide an exhaust gas processing apparatus that is effective in reducing the size of the high concentration gas processing means.

  Further, according to the present invention, the exhaust gas from the cleaning tank can be processed by a small exhaust gas processing apparatus, and an exhaust gas processing system for the cleaning tank that can reduce air pollution can be provided.

  The invention according to claim 1 of the present invention is a low-concentration gas processing means for processing an organic solvent gas of exhaust gas exhausted by a local exhaust device installed at a source of the organic solvent in an exhaust gas processing device for removing an organic solvent in the exhaust gas. And a high-concentration gas processing means that directly processes the organic solvent gas of the generation source, each of which is an exhaust gas processing apparatus that can individually introduce exhaust gas. Both the sucked gas and the gas exhausted from the local exhaust system can be processed at the same time, and the amount of organic solvent gas discharged from the source can be reduced by direct suction from the source. Further, since the air volume of the local exhaust device is reduced, the exhaust gas treatment device can be downsized.

  The invention according to claim 2 of the present invention adsorbs the organic solvent gas in the exhaust gas as the low-concentration gas processing means, adsorbs the organic solvent gas to the atmosphere after removing the organic solvent gas, and adsorbs the adsorbing means. A desorption concentration means for desorbing, concentrating and introducing the organic solvent gas into the high concentration gas treatment means; and a liquefaction means for cooling the organic solvent gas concentrated by the desorption concentration means as a high concentration gas treatment means to form a liquid. An organic solvent gas recovery apparatus comprising: a high-concentration gas introduction device for directly introducing a high-concentration organic solvent gas into the liquefaction device, wherein the low-concentration gas treatment is performed. Concentration using adsorption means as means, liquefaction means by cooling as high-concentration gas processing means, concentrated gas and high-concentration gas introduction of low-concentration gas processing means with high-concentration gas processing means By processing both gas introduced by stages, an effect that the configuration can be simplified.

  The invention according to claim 3 of the present invention measures the organic solvent gas concentration of the exhaust gas of the local exhaust device introduced into the low concentration gas processing means, and the organic solvent gas concentration is high according to the organic solvent gas concentration. The exhaust gas treatment device according to claim 2, further comprising a flow rate adjusting means for increasing the flow rate of the high-concentration gas introduction means and decreasing the flow rate of the high-concentration gas introduction means when the organic solvent gas concentration is reduced. By adjusting the flow rate of the high-concentration gas introduction means according to the exhaust gas concentration from the local exhaust device, it is possible to suppress the exhaust gas concentration of the local exhaust device from becoming high, so that the low-concentration gas processing means can be downsized. Has an effect.

  The invention according to claim 4 of the present invention further comprises a high concentration gas branching means for introducing a part of the high concentration gas introduced by the high concentration gas introduction means to the adsorption means so as to increase the concentration of the organic solvent in the adsorption means. The exhaust gas treatment apparatus according to claim 2 or 3, wherein the concentration of the organic solvent in the adsorption means becomes high, so that the concentration of the concentrated gas obtained by desorption from the adsorption means can be increased. Have

  According to the fifth aspect of the present invention, the flow rate adjusting means for adjusting the amount of the high concentration gas introduced into the adsorption means is a high concentration gas branching means so as to optimize the organic solvent concentration in the adsorption means. The exhaust gas treatment apparatus according to claim 4 is provided, wherein the amount of the high-concentration gas introduced into the low-concentration gas treatment means is adjusted by the flow rate adjustment means, and the low-concentration due to the introduction of an unnecessarily high-concentration gas. It has the effect that it is possible to suppress the concentration reduction of the concentrated gas due to the lack of capacity of the gas processing means and the lack of high concentration gas.

  The invention according to claim 6 of the present invention includes the exhaust gas treatment apparatus according to any one of claims 1 to 5, a cleaning tank for storing an organic solvent, and a local exhaust apparatus for exhausting an organic solvent gas generated from the cleaning tank. An exhaust gas treatment system for introducing the exhaust gas of the local exhaust device into the low concentration gas treatment means and introducing the high concentration organic solvent gas in the cleaning tank into the high concentration gas treatment means by the high concentration gas introduction means. In addition, the amount of the organic solvent gas discharged from the cleaning tank can be reduced by sucking the high-concentration organic solvent gas in the cleaning tank, so that the air volume of the local exhaust device can be reduced. Further, if the air volume of the local exhaust device can be reduced, the low concentration gas processing means can be reduced in size.

  In the invention according to claim 7 of the present invention, the organic solvent stored by the heating means installed in the cleaning tank is heated to generate vapor of the organic solvent, and the vapor is cooled by the cooling means installed on the inner wall of the cleaning tank. In the cleaning tank, the steam is stored in the cleaning tank, and the object to be cleaned is immersed in an organic solvent and cleaned with the steam, and the exhaust gas processing for processing the organic solvent gas discharged from the cleaning apparatus. The exhaust gas treatment system according to claim 6, wherein the gas storing position, that is, the gas above the vapor line is introduced into the high concentration gas treatment means by the high concentration gas introduction means. This has the effect of reducing the amount of organic solvent gas discharged. Further, since the emission amount is reduced, the exhaust gas can be normalized with a small exhaust gas treatment device.

  The invention according to claim 8 of the present invention is the exhaust gas treatment system according to claim 7, wherein the gas under the vapor line is introduced into the high concentration gas treatment means by the high concentration gas introduction means. Since the lower part is a high-concentration gas close to 100%, it has an effect that cooling and liquefaction can be made relatively simple.

  The invention according to claim 9 of the present invention is the exhaust gas treatment system according to claim 7 or 8 which measures the concentration of the low-concentration gas and controls the heating means and cooling means of the cleaning tank. Measures the concentration of gas discharged from the tank and controls the heating means and cooling means to suppress the evaporation of organic solvent gas when the concentration increases, so the amount of exhaust gas from the cleaning tank can be reduced and a small exhaust gas treatment device It has the effect that it can be processed with.

  Further, the invention according to claim 10 of the present invention is provided with an atmospheric temperature measuring means for measuring the atmospheric temperature in which the cleaning tank is installed, and from the concentration of the low concentration gas and the atmospheric temperature measured by the atmospheric temperature measuring means, the heating means The exhaust gas treatment system according to any one of claims 7 to 9, wherein the cooling means is controlled. The discharge of the organic solvent from the cleaning tank is due to evaporation of the organic solvent, and the ambient temperature. Therefore, the concentration of the organic solvent gas discharged by the local exhaust device and the ambient temperature are measured, and the cleaning tank is controlled, so that the discharge of the organic solvent gas is more reliably suppressed.

  The invention described in claim 11 further comprises level detecting means for detecting the position of the vapor line, and the flow rate of the high concentration gas introducing means is adjusted by the flow rate adjusting means in accordance with a signal from the level detecting means. Since the position of the vapor line can be detected, the vapor line is increased by increasing the flow rate of the high concentration gas introducing means when the vapor line is raised. It has the effect | action that it can reduce and discharge | emission of the organic solvent gas from a washing tank can be reduced.

  The invention according to claim 12 of the present invention is characterized in that the flow rate of the high concentration gas introducing means is adjusted by the flow rate adjusting means according to the signal of the level detecting means, and at the same time the heating means and cooling means of the cleaning tank are controlled. The exhaust gas treatment system according to claim 11, wherein not only the flow rate of the high concentration gas introduction means but also the heating means and cooling means of the cleaning tank can be controlled. By increasing the flow rate of the introducing means, reducing the capacity of the heating means, and increasing the capacity of the cooling means, the position of the vapor line can be lowered.

  The invention according to claim 13 of the present invention is the exhaust gas treatment system according to claim 11 or 12, further comprising alarm output means for outputting an alarm when the position of the vapor line detected by the level detection means rises. The alarm causes the operator to know that the operation of the cleaning tank is abnormal and the organic solvent gas may be discharged due to the rise of the vapor line, and the appropriate action can be taken.

  The invention according to claim 14 of the present invention is the exhaust gas treatment system according to any one of claims 11 to 13, wherein the suction port is moved in accordance with the position of the vapor line detected by the level detection means. Since the position of the suction port introduced into the high concentration gas introducing means in the cleaning tank is stabilized with reference to the vapor line, the concentration of the gas to be sucked can be stabilized.

  The invention described in claim 15 is characterized in that at least one of the suction amount of the high concentration gas introducing means, the heating means of the cleaning tank, and the cooling means is controlled so that the position of the vapor line does not change. The exhaust gas treatment system according to any one of claims 11 to 13, wherein the position of the vapor line can be stabilized, so that the exhaust gas concentration is stabilized and the concentration of the gas introduced into the exhaust gas treatment device varies. It has the effect of reducing.

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

(Embodiment 1)
FIG. 1 is a block diagram showing the configuration of the exhaust gas treatment apparatus of the present invention.

  As shown in the figure, an organic solvent gas discharged from a facility using an organic solvent such as painting, printing, industrial cleaning, etc. is introduced into the exhaust gas treatment apparatus 1, and the organic solvent gas contained in the exhaust gas is removed and released into the atmosphere. The Here, the gas introduced into the exhaust gas treatment apparatus 1 is a low-concentration organic solvent gas introduced into the low-concentration gas treatment means 2 and a high-concentration organic solvent gas is introduced into the high-concentration gas treatment means 3 to perform a removal treatment. . Here, the low-concentration organic solvent gas is, for example, a gas discharged from an organic solvent gas discharge source using a local exhaust device, and is a gas diluted in the atmosphere to be sucked by the local exhaust device. The concentration ranges from several hundred ppm to 1% or less.

  The high-concentration organic solvent gas is, for example, a gas sucked directly from the vicinity of the generation source or from the generation source so as not to dilute into the atmosphere, and contains 1% or more organic solvent gas.

  Here, the low-concentration gas treatment means 2 and the high-concentration gas treatment means 3 are an adsorption method using an adsorbent such as activated carbon, zeolite, alumina, silica gel, a combustion method that decomposes at a high temperature, a catalyst method that uses a catalyst, Absorption method using absorption liquid, ozone, UV, plasma decomposition, cooling, cooling aggregation method by pressure cooling, biodegradation method using microorganisms and enzymes, and other known methods for treating organic solvents can be used. The low-concentration gas treatment means 2 can be used by optimizing the above-described method for a low-concentration organic solvent gas, and similarly the high-concentration gas treatment means 3 can be optimized for a high-concentration organic solvent gas. .

  In the above configuration, the exhaust gas treatment apparatus 1 includes the low concentration gas treatment means 2 and the high concentration gas treatment means 3, and one unit is provided for both the low concentration organic solvent gas and the high concentration organic solvent gas. It is possible to cope with the apparatus, and furthermore, since the low-concentration organic solvent gas and the high-concentration organic solvent gas can be sucked and processed at the same time, two kinds of concentrations of gas can be processed simultaneously.

  In addition, a local exhaust device is usually installed at the source that discharges the organic solvent gas to prevent diffusion into the work environment, and the organic solvent gas discharged from the source is collected by the local exhaust device, and is taken outdoors. It is discharging. Here, in order to prevent air pollution, the exhaust gas treatment device 1 is installed in the end of pipe of the local exhaust device to purify the organic solvent gas in the exhaust gas discharged.

  On the other hand, there is also a method of reducing the discharge of the organic solvent by suppressing the generation of the organic solvent gas from the generation source by sucking and processing the organic solvent gas generated from the inside or near the generation source.

  Since the exhaust gas treatment apparatus 1 of the present invention can treat a low-concentration organic solvent gas and a high-concentration organic solvent gas at the same time, the exhaust gas treatment of both methods can be performed by a single device.

  Therefore, the apparatus can be downsized.

(Embodiment 2)
FIG. 2 is a block diagram showing the configuration of the exhaust gas treatment apparatus 1 of the present invention. The same parts as those in the first embodiment of the present invention are denoted by the same reference numerals and description thereof is omitted.

  In the figure, the low concentration gas processing means 2 is constituted by an adsorption means 4 and a desorption means 5, and the high concentration gas processing means 3 is constituted by a liquefaction means.

  The adsorbing means 4 includes, for example, an adsorbent such as activated carbon, silica gel, zeolite, and alumina, introduces a low concentration organic solvent gas, adsorbs an organic solvent gas component in the low concentration organic solvent gas, and is substantially organic. Release the solvent gas to the atmosphere.

  The adsorption means 4 may be used by switching one or more adsorption towers filled with an adsorbent. Further, the adsorbent may be molded into a honeycomb shape and attached to a honeycomb-shaped substrate, or a cylindrical rotor may be used.

  The desorption means 5 desorbs the organic solvent gas adsorbed by the adsorption means 4 from the adsorbent, regenerates the adsorbent, and sends the desorbed organic solvent gas to the liquefaction means 6 of the high-concentration gas processing means 3. The desorbed organic solvent gas is concentrated as compared with the introduced low concentration organic solvent gas.

  Here, the desorption method of the desorption means 5 from the adsorbent includes desorption by heat such as steam, heated air, heated inert gas, and direct heating of the adsorbent, so-called TSA method, desorption by depressurization, so-called PSA method, etc. Known methods can be used.

  Next, the liquefying means 6 which is the high concentration gas processing means 3 introduces the high concentration organic solvent gas from the high concentration gas introduction means 7 and the concentrated gas from the desorption means 5 and cools to liquefy the organic solvent gas. The liquefied organic solvent is recovered and reused or becomes waste.

  Here, the liquefying means 6 may be a known method as long as it is a means for cooling the gas. For cooling, a cooling liquid using a chiller, a refrigerant using a refrigeration cycle, or the like can be used.

  The high-concentration gas introduction means 7 is composed of pipes such as pipes, a pump and a blower, and sucks the high-concentration organic solvent gas from the generation source.

  Next, the gas that has not been condensed by the liquefying means 6 is mixed with the gas treated by the adsorption means 4 and discharged.

  Here, the uncondensed gas may be mixed with the low-concentration organic solvent gas and returned to the inlet of the adsorption means 4, or may be returned to the source from which the high-concentration solvent gas has been introduced.

  In the above configuration, since the high concentration organic solvent gas sucked from the generation source is processed by the high concentration gas processing means 3, the amount of the organic solvent gas discharged from the generation source can be reduced. Therefore, the air volume of the local exhaust device can be reduced, and the amount of low-concentration organic solvent gas to be processed can be reduced.

  Therefore, the adsorbent used for the adsorption means 4 of the low concentration gas treatment means 2 can be reduced, and the low concentration gas treatment means 2 can be miniaturized.

  Therefore, the exhaust gas treatment apparatus of the present invention processes the high-concentration organic solvent gas and the low-concentration organic solvent gas simultaneously in one apparatus, thereby downsizing the apparatus and reliably processing the exhaust gas containing the organic solvent gas. It becomes possible to do.

(Embodiment 3)
FIG. 3 is a block diagram showing the configuration of the exhaust gas treatment apparatus 1 of the present invention. In addition, the same number is attached | subjected to the part same as Embodiment 1, 2 of this invention, and description is abbreviate | omitted.

  In the figure, the branching means 8 is provided in the high concentration gas introducing means 7, branches a part of the high degree organic solvent gas sucked by the high concentration gas introducing means 7, and adjusts the flow rate by the flow rate adjusting valve 9. Then, it is introduced into the low concentration gas introduction means 2.

  The measuring means 10 measures the concentration of the low-concentration organic solvent gas introduced into the low-concentration gas processing means 2 and sends a signal to the control means 11. The control means 11 adjusts the flow rate adjusting valve 9 and the flow rate adjusting valve 12 in accordance with the measured concentration of the low-concentration organic solvent gas, and includes a microcomputer programmed with the contents.

  Here, the measuring means 10 may be any means as long as it can measure the concentration of the organic solvent gas, and a semiconductor type gas sensor, an FID type, a PID type measuring instrument, an NDIR type measuring instrument, or the like can be used. The control means 11 is composed of an electric circuit including a microcomputer. The branch means 8 may use a branch pipe.

  In the above configuration, the concentration of the low-concentration organic solvent gas is measured by the measuring means 10, and when the concentration becomes high, the flow rate adjustment valve 12 is opened to increase the flow rate of the high-concentration gas introduction means 7, and when the concentration becomes low, the flow rate adjustment valve 12 is closed. Thus, the control means 11 controls the flow rate of the high-concentration gas introduction means 7 to be reduced.

  Thereby, the concentration fluctuation | variation of the low concentration organic solvent gas introduced into the low concentration gas processing means 2 is relieved.

  Further, a part of the high-concentration organic solvent gas is introduced into the low-concentration gas processing means 2 by the branching means 8 provided in the high-concentration gas introduction means 7. The introduction amount is adjusted by the flow rate adjusting valve 9 in response to a signal from the control means 11.

  This makes it possible to increase the concentration of the organic solvent adsorbed on the adsorption means 4 of the low concentration gas processing means 2 and increase the concentration of the concentrated gas obtained by the desorption means 5.

  Therefore, the liquefaction efficiency in the liquefaction means 6 can be improved.

  Further, by adjusting the flow rate by the flow rate adjusting means 9, it is possible to suppress the adsorption means 4 from being broken through and releasing the gas containing the organic solvent gas.

  As described above, the concentration and amount of the organic solvent gas processed by the adsorbing means 4 are adjusted by the flow rate of the high concentration gas introduced into the high concentration gas processing means 3, and a part of the high concentration gas is used as the low concentration gas processing means. By introducing, the performance of the adsorbent of the adsorbing means 4 can be optimized, the liquefying means 6 can be operated efficiently, the apparatus is downsized, and exhaust gas containing an organic solvent is reliably purified. It becomes possible.

(Embodiment 4)
FIG. 4 is a block diagram showing the configuration of the exhaust gas treatment system of the present invention. In addition, the same number is attached | subjected to the part same as Embodiment 1-3 of this invention, and description is abbreviate | omitted.

  In the figure, the cleaning tank 13 shows a general two-tank degreasing cleaning tank as an example. The organic solvent 19 is stored in the cleaning tank, and the storage part is divided into two tanks. One tank is provided with a heating means 15 for heating the organic solvent 19 near the boiling point to generate an organic solvent vapor 17.

  Further, a cooling means 16 is installed on the wall surface of the cleaning tank 13, and the generated organic solvent vapor 17 is cooled, liquefied and returned to the stored organic solvent 19.

  Further, by cooling with the cooling means 16, a vapor line 18 in which the organic solvent vapor 17 is stored in the cleaning tank 13 is formed.

  The local exhaust device 14 collects the organic solvent gas generated from the cleaning tank 13 and introduces it into the low concentration gas processing means 2 of the exhaust gas processing device 1.

  Further, the high concentration gas introduction means 7 of the exhaust gas treatment apparatus 1 sucks the gas above the vapor line 18 in the cleaning tank 13 and introduces it into the high concentration gas treatment means 3.

  Here, the local exhaust device 14 includes a fan, duct piping, and a hood for collection. Moreover, the cooling means 16 arrange | positions piping of cooling water on the inner wall of the washing tank 13, and makes cooling water with a chiller etc. The heating means 15 circulates hot water heated by a heater or a boiler.

  In the above-described configuration, the high concentration organic solvent gas stored in the upper portion of the vapor line 18 in the cleaning tank 13 is sucked and processed by the high concentration gas introducing means 7 to be discharged from the cleaning tank 13 and the local exhaust device 14. The concentration and amount of the organic solvent gas sucked in can be reduced. Therefore, the air volume of the local exhaust device 14 can be reduced, and the low concentration gas processing means 2 of the exhaust gas processing device 1 can be reduced in size.

  Moreover, since the gas discharged | emitted with the local exhaust apparatus 14 is processed with the exhaust gas processing apparatus 1, the organic solvent discharge | released to air | atmosphere can be processed reliably.

  As described above, the gas discharged from the cleaning tank 13 can be processed in a small exhaust gas processing apparatus by simultaneously processing the high concentration gas in the cleaning tank and the low concentration gas from the local exhaust apparatus with one exhaust gas processing apparatus. The exhaust gas can be reliably processed.

(Embodiment 5)
FIG. 5 is a block diagram showing the configuration of the exhaust gas treatment system of the present invention. In addition, the same number is attached | subjected to the part same as Embodiment 1-4 of this invention, and description is abbreviate | omitted.

  In the figure, the high-concentration gas introducing means 7 sucks the organic solvent vapor 17 stored in the lower part of the vapor line 18 in the cleaning tank 13.

  In the above configuration, by sucking the organic solvent vapor 17 close to 100%, it is possible to efficiently liquefy even if the cooling temperature of the liquefying means 6 is increased. For example, when the organic solvent gas is dichloromethane, when a gas having a concentration of several to several tens of percent is liquefied, it cannot be sufficiently liquefied unless it is cooled to -10 to -30 ° C. It becomes possible to liquefy at a temperature of 0 ° C. or higher.

(Embodiment 6)
FIG. 6 is a block diagram showing the configuration of the exhaust gas treatment system of the present invention. In addition, the same number is attached | subjected to the part same as Embodiment 1-5 of this invention, and description is abbreviate | omitted.

  In the figure, the control means 11 of the exhaust gas treatment apparatus 1 receives the concentration of the low-concentration organic solvent gas measured by the measurement means 10 and the atmospheric temperature measured by the atmospheric temperature measurement means 20, and controls the flow rate adjusting valve 12 and the cleaning tank 13. There is a microcomputer for controlling the cooling means 16 and the heating means 15 and the contents of which are programmed.

  In the above configuration, the measurement means 10 and the ambient temperature measurement means 20 measure the concentration and temperature of the low-concentration organic solvent gas collected by the local exhaust apparatus 14 introduced into the low-concentration gas processing means 2. When the concentration of the organic solvent gas is high, the capability of the low concentration gas processing means 2 is insufficient, and the organic solvent gas may be released to the atmosphere. Further, if the concentration is low, the capability of the low-concentration gas processing means 2 becomes excessive, and the concentration of the concentrated gas introduced into the liquefying means 6 via the desorption means 5 is reduced, so that the liquefaction efficiency of the liquefying means 6 may be reduced There is sex.

  Therefore, in order to suppress fluctuations in the concentration of the low-concentration organic solvent gas introduced into the low-concentration gas processing means 2, the control means 11 can control the capability of the heating means 15 in the cleaning tank 13 according to the concentration measured by the measurement means 10 or The temperature and the capacity or temperature of the cooling means 16 are adjusted. Further, the control means 11 is inputted with the atmosphere temperature by the atmosphere temperature measuring means 20 and used for controlling the cooling means 16 and the heating means 15 described above. Here, the ambient temperature measuring means 20 may be a thermistor, a thermocouple, a platinum resistance temperature detector, or the like.

  Here, when the concentration of the organic solvent gas is high, the temperature of the heating means 15 is lowered to lower the generation amount of the organic solvent vapor 17, and the temperature of the cooling means 16 is lowered to reduce the discharge of the organic solvent gas from the cleaning tank 13. To do. Conversely, when the concentration is low, the concentration can be increased by raising the temperature of the heating means 15 and raising the temperature of the cooling means 16.

  In addition, more accurate control is possible by adding the atmospheric temperature measured by the atmospheric temperature measuring means 20 to the control of the control means 11.

  As described above, by stabilizing the concentration of the low-concentration organic solvent gas introduced into the low-concentration gas treatment means 2 by controlling the operating conditions of the cleaning tank 13, the exhaust gas treatment device can be downsized. In addition, the organic solvent gas can be reliably processed.

(Embodiment 7)
FIG. 7 is a block diagram showing the configuration of the exhaust gas treatment system of the present invention. In addition, the same number is attached | subjected to the part same as Embodiment 1-6 of this invention, and description is abbreviate | omitted.

  In the figure, the level detection means 21 measures the position of the vapor line 18 in the cleaning tank 13 and sends a signal to the control means 11. The alarm means 22 determines from the signal detected by the level detection means 21 that the level of the vapor line 18 has increased by the control means 11 and outputs an alarm to the outside.

  Here, the level detection means 21 may be any method that can detect the vapor line 18. A position detection method using ultrasonic waves, infrared rays, or the like, a method for detecting condensation of organic solvent vapor, or the like can be used. The alarm means 22 may be any method that informs the user of an alarm, such as a buzzer, LED, or lamp.

  In the above configuration, the position of the vapor line 18 is detected by the level detection means 21, and in addition to the concentration measured by the measurement means 10, the heating means 15, the cooling means 16, and the flow rate adjustment valve 12 are set according to the position of the vapor line 18. Therefore, the position of the vapor line 18 can be more accurately controlled, and the discharge of the organic solvent gas from the cleaning tank 13 can be stabilized, so that the treatment can be reliably performed with a small exhaust gas treatment apparatus. .

(Embodiment 8)
FIG. 8 is a block diagram showing the configuration of the exhaust gas treatment system of the present invention. In addition, the same number is attached | subjected to the part same as Embodiment 1-7 of this invention, and description is abbreviate | omitted.

  In the figure, the suction port moving means 23 receives the signal of the level detecting means 21 from the control means 11 and moves the suction port from the cleaning tank 13 of the high concentration gas introducing means 7 in the vertical direction according to the position of the vapor line 18. To do.

  Here, the suction port moving means 23 can be configured by a mechanism using a motor.

  In the above configuration, even when the position of the vapor line is moved, the level detection means 21 detects the position of the vapor line and the suction port is moved by the suction port moving means 23. When installed in the upper atmosphere, when the vapor line rises, the suction port becomes the lower part of the vapor line 18, and the high-concentration organic solvent vapor 17 is introduced into the high-concentration gas treatment 3, so that the treatment cannot be performed. However, by detecting that the vapor line 18 has risen and moving the suction port, it is possible to always introduce a stable concentration of gas into the high concentration gas processing means 3.

  Therefore, it is possible to reduce the size of the high-concentration gas processing means 3 and supply an exhaust gas processing apparatus that can reliably process even if the vapor line 18 moves.

  It is useful as an exhaust gas treatment device or exhaust gas treatment system that is installed in facilities that emit volatile organic solvents such as printing, painting, adhesion, chemical product manufacturing, and industrial cleaning.

The block diagram which shows the structure of Embodiment 1 of this invention. The block diagram which shows the structure of Embodiment 2 of this invention. The block diagram which shows the structure of Embodiment 3 of this invention. The block diagram which shows the structure of Embodiment 4 of this invention. The block diagram which shows the structure of Embodiment 5 of this invention. The block diagram which shows the structure of Embodiment 6 of this invention. The block diagram which shows the structure of Embodiment 7 of this invention The block diagram which shows the structure of Embodiment 8 of this invention. Block diagram showing the configuration of a conventional exhaust gas treatment device Block diagram showing the configuration of a conventional gas recovery device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exhaust gas processing apparatus 2 Low concentration gas processing means 3 High concentration gas processing means 4 Adsorption means 5 Desorption means 6 Liquefaction means 7 High concentration gas introduction means 8 Branch means 9 Flow control valve 10 Measuring means 11 Control means 12 Flow control valve 13 Cleaning Tank 14 Local exhaust device 15 Heating means 16 Cooling means 17 Organic solvent vapor 18 Vapor line 19 Organic solvent 20 Atmospheric temperature measuring means 21 Level detecting means 22 Alarm means 23 Suction port moving means

Claims (15)

In an exhaust gas treatment apparatus for removing organic solvent in exhaust gas, a low-concentration gas treatment means for treating the organic solvent gas of exhaust gas exhausted by a local exhaust device installed in the organic solvent generation source and the organic solvent gas of the generation source directly An exhaust gas treatment apparatus comprising high-concentration gas treatment means for treatment and capable of individually introducing exhaust gas. As the low-concentration gas treatment means, the organic solvent gas in the exhaust gas is adsorbed and the gas after the organic solvent gas is removed is released into the atmosphere, and the organic solvent gas adsorbed on the adsorption means is desorbed, concentrated, and concentrated. In the organic solvent gas recovery apparatus, comprising: a desorption concentration means to be introduced into the concentration gas treatment means; and a liquefaction means for cooling the organic solvent gas concentrated by the desorption concentration means as a high concentration gas treatment means to form a liquid. The exhaust gas treatment apparatus according to claim 1, further comprising high concentration gas introduction means for directly introducing high concentration organic solvent gas into the means. Measure the organic solvent gas concentration of the exhaust gas of the local exhaust device to be introduced into the low concentration gas processing means, and according to the organic solvent gas concentration, increase the flow rate of the high concentration gas introduction means when the organic solvent gas concentration is high, The exhaust gas treatment apparatus according to claim 2, further comprising a flow rate adjusting unit configured to reduce a flow rate of the high concentration gas introducing unit when the organic solvent gas concentration is reduced. The exhaust gas treatment apparatus according to claim 2 or 3, further comprising a high concentration gas branching means for introducing a part of the high concentration gas introduced by the high concentration gas introduction means into the adsorption means so as to increase the concentration of the organic solvent in the adsorption means. . The exhaust gas treatment apparatus according to claim 4, wherein the high-concentration gas branching unit includes a flow rate adjusting unit that adjusts the amount of the high-concentration gas introduced into the adsorption unit so as to optimize the organic solvent concentration in the adsorption unit. An exhaust gas treatment device according to any one of claims 1 to 5, a cleaning tank for storing an organic solvent, and a local exhaust device for exhausting an organic solvent gas generated from the cleaning tank as an exhaust gas, the exhaust gas of the local exhaust device being reduced An exhaust gas treatment system which is introduced into the concentration gas treatment means and introduces the high concentration organic solvent gas in the cleaning tank into the high concentration gas treatment means by the high concentration gas introduction means. The organic solvent stored by the heating means installed in the cleaning tank is heated to generate an organic solvent vapor, the vapor is cooled by the cooling means installed on the inner wall of the cleaning tank, and the vapor is stored in the cleaning tank, In a cleaning apparatus for cleaning an object to be cleaned with an organic solvent and cleaning with steam and an exhaust gas processing for processing an organic solvent gas discharged from the cleaning apparatus, a position where the steam is stored in the cleaning tank, that is, above the vapor line The exhaust gas treatment system according to claim 6, wherein the gas is introduced into the high concentration gas treatment means by the high concentration gas introduction means. The exhaust gas treatment system according to claim 7, wherein the gas below the vapor line is introduced into the high concentration gas treatment means by the high concentration gas introduction means. The exhaust gas treatment system according to claim 7 or 8, wherein the concentration of the low concentration gas is measured to control the heating means and the cooling means of the cleaning tank. An atmosphere temperature measuring means for measuring the atmosphere temperature in which the cleaning tank is installed is provided, and the heating means and the cooling means are controlled from the concentration of the low concentration gas and the atmosphere temperature measured by the atmosphere temperature measuring means. The exhaust gas treatment system according to any one of 7 to 9. The exhaust gas according to any one of claims 7 to 10, further comprising level detection means for detecting a position of the vapor line, wherein the flow rate of the high-concentration gas introduction means is adjusted by the flow rate adjustment means in accordance with a signal from the level detection means. Processing system. 12. The exhaust gas treatment system according to claim 11, wherein the flow rate of the high-concentration gas introduction means is adjusted by the flow rate adjustment means based on the signal of the level detection means, and at the same time, the heating means and cooling means of the cleaning tank are controlled. The exhaust gas treatment system according to claim 11 or 12, further comprising alarm output means for outputting an alarm when the position of the vapor line detected by the level detection means rises. The exhaust gas treatment system according to any one of claims 11 to 13, wherein the suction port is moved in accordance with the position of the vapor line detected by the level detection means. The exhaust gas treatment according to any one of claims 11 to 13, wherein at least one of the suction amount of the high concentration gas introducing means, the heating means of the cleaning tank, and the cooling means is controlled so that the position of the vapor line does not change. system.

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