JP2010131564A - Exhaust gas treatment apparatus and treatment method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance reliability by safely reducing waste ozone less than a given level, and to reduce facility cost and running cost of a waste ozone treatment apparatus using activated carbon and/or a catalyst. <P>SOLUTION: Exhaust gas 1 containing ozone or the like flows into a flow path 2 and flows into an activated carbon column 4, where gas like ozone contained in the exhaust gas 1 is decomposed by activated carbon. The ozone gas concentration is measured by a gas concentration meter 3 set in the flow path of the decomposed exhaust gas, the exhaust gas containing ozone is diluted with air in a branch flow path 11 into which dilution gas like air flows, and released to the atmosphere by a blower 6. A controlling device 7 transmits 9 an alarm, cuts off 10 inflow of the exhaust gas, switches the gas flow path, and controls 19 the flow of the dilution air, based on the measured value of the gas concentration meter 3, and a regulation value CA of atmospheric releasing ozone and ozone concentration CH causing ignition of the activated carbon, which are set values received from an input means 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an apparatus for treating exhaust gas containing gases such as ozone, dioxins, and odor gas, and in particular, treats exhaust gas containing these gases with activated carbon and / or a catalyst or dilutes with air or the like. The present invention relates to an exhaust gas treatment apparatus and a treatment method.

  Ozone gas is widely used for disinfection and deodorization of water and sewage, treatment of factory effluent, and deodorization equipment. On the other hand, ozone is a main component of a photochemical oxidant that is an air pollutant and adversely affects human bodies and plants. Therefore, it is necessary to remove unused ozone (hereinafter referred to as exhausted ozone) as much as possible. According to environmental standards related to air pollution, the photochemical oxidant is determined to be 0.06 ppm or less per hour.

  Waste ozone treatment methods include adsorption / decomposition with activated carbon, decomposition with catalyst, self-decomposition of ozone by heating, cleaning with chemicals, etc., treatment effect, maintenance and economics It is selected in consideration of etc.

  As a conventional technique for treating ozone, for example, Non-Patent Document 1 discloses a method of adsorption / decomposition with activated carbon. According to this disclosed technique, ozone can be treated reliably, and maintenance is also replaced with activated carbon. It is an addition only and has the advantage that heating and waste liquid treatment are unnecessary, and is widely used. However, when exhaust ozone having a high concentration of several hundred ppm flows in, there is a risk of ignition due to a rapid oxidation reaction, and measures to avoid this are necessary.

Non-Patent Document 1 shows an example of an exhaust ozone decomposing apparatus in which a mist separator, a catalyst heating heater, a manganese catalyst tower, an activated carbon tower, and a blower are connected in this order after the exhaust ozone inlet. Manganese catalysts can decompose ozone at a higher concentration than activated carbon. The ozone concentration in the gas flowing into the activated carbon by the manganese catalyst is reduced to 0.1 ppm or less, and the activated carbon is positioned as a backup for further reliably reducing to 0.06 ppm or less. In this example, water purification treatment is targeted, and the exhaust ozone concentration at the inlet is assumed to be 4 g / Nm ^{3 at the} maximum.

In addition, as a conventional technique for treating ozone, for example, Patent Document 1 discloses an exhaust ozone treatment apparatus in which an activated carbon tower is disposed at the rear stage of the catalyst tower, as in the processing apparatus of Non-Patent Document 1 described above. A method of issuing an alarm by measuring the ozone concentration of the gas is disclosed. In the method of Patent Document 1, it is possible to prevent the exhaust gas containing high-concentration ozone from flowing into the activated carbon tower by detecting a decrease in the ozonolysis performance of the catalyst and replacing the catalyst.
“Water Supply Facility Design Guidelines”, Issued by Japan Waterworks Association, issued on March 31, 2000, pages 318-312 Japanese Patent Laid-Open No. 11-70321

  By the way, depending on the operating conditions and the quality of non-treated water, when exhaust gas containing ozone is recycled into water to be treated again, or when ozone is used for treatment such as sewage and plant abolition. The ozone concentration becomes a low concentration of about 100 ppm or less. For example, in an experiment conducted by the inventors for ozone treatment of sewage secondary treated water for the purpose of disinfection and decolorization / deodorization, the exhaust ozone concentration was 50 ppm or less at the maximum and an average of about 20 ppm. Thus, when the exhaust ozone concentration is sufficiently lower than the concentration at which the activated carbon is ignited (for example, several hundred ppm), the exhaust ozone treatment can be performed only with the activated carbon.

  Nevertheless, when the configuration including the catalyst and activated carbon shown in Non-Patent Document 1 or Patent Document 1 is used as the exhaust ozone treatment device in this case, the operating cost of the heating heater for the catalyst is Equipment costs for the catalyst tower and catalyst maintenance are required.

  In addition, the ozone concentration of the treatment gas after exhaust ozone treatment needs to be kept below the regulation value, but the regulation value is as low as 0.06 ppm, which is more than this regulation value for direct measurement and warning. There is a need for a highly sensitive and expensive ozone densitometer that can detect even low concentrations.

  An object of the present invention is to solve the above-mentioned problems of the prior art, in an exhaust ozone treatment apparatus using activated carbon and / or a catalyst, to safely reduce exhaust ozone to a predetermined value or less, and to reduce facility costs and operation costs. An object of the present invention is to provide a waste ozone treatment apparatus and a treatment method that are highly reliable and economical for removing waste ozone.

In order to solve the above problems, the present invention mainly adopts the following configuration.
An exhaust gas decomposition tower that decomposes exhaust gas that is restricted to atmospheric release with activated carbon and / or a catalyst, a blower that releases the gas decomposed in the exhaust gas decomposition tower to the atmosphere, and air, nitrogen, etc. on the upstream side of the blower From a dilution gas pipe that communicates a non-removal target gas to the exhaust gas flow path, a gas concentration meter that measures the exhaust gas concentration provided in the exhaust gas flow path, a measured value from the gas concentration meter, and input operation means An exhaust gas treatment apparatus comprising a control unit for instructing a gas concentration alarm based on an input set value of the exhaust gas, wherein the gas concentration meter The control unit measures the concentration of the exhaust gas before dilution and is disposed in the flow path and on the upstream side of the dilution gas pipe. Concentration regulation And then, a predetermined value of less than the calculated value calculated from said input setting value and the dilution ratio, a structure for indicating a warning to the gas concentration measured reaches.

  An exhaust gas treatment apparatus characterized by that.

  In addition, an exhaust gas decomposition tower that decomposes the exhaust gas regulated to be released into the atmosphere with activated carbon and / or a catalyst, a blower that releases the gas decomposed in the exhaust gas decomposition tower to the atmosphere, and air and nitrogen on the upstream side of the blower Dilution gas piping for communicating a non-removable gas such as the exhaust gas flow path, a gas concentration meter for measuring the exhaust gas concentration provided in the exhaust gas flow path, and a measured value and input operation from the gas concentration meter An exhaust gas treatment apparatus comprising: a control unit for instructing a gas concentration alarm based on an input set value from the means, wherein the gas concentration meter is disposed on the upstream side of the dilution gas pipe and is diluted The concentration of the previous exhaust gas is measured, and the exhaust gas flow path after the dilution gas pipe connection is connected to the first flow path connected to the blower via the exhaust gas decomposition tower and the second directly connected to the blower. Three-way valve that forms a flow path with The control unit is configured to set the input set value by the input operation means as a gas concentration regulation value for atmospheric emission, and to a first predetermined value less than a calculated value calculated from the input set value and a dilution rate, When the measured gas concentration reaches, the three-way valve is instructed to switch from the second flow path to the first flow path, and the control unit calculates from the input set value and the dilution rate. A warning is instructed when the measured gas concentration reaches a second predetermined value less than the calculated value.

  In addition, an exhaust gas decomposition tower that decomposes the exhaust gas regulated to be released into the atmosphere with activated carbon and / or a catalyst, a blower that releases the gas decomposed in the exhaust gas decomposition tower to the atmosphere, and air and nitrogen on the upstream side of the blower Dilution gas piping for communicating a non-removable gas such as the exhaust gas flow path, a gas concentration meter for measuring the exhaust gas concentration provided in the exhaust gas flow path, and a measured value and input operation from the gas concentration meter An exhaust gas treatment apparatus comprising: a control unit for instructing a gas concentration alarm based on an input set value from the means, wherein the gas concentration meter is disposed on the upstream side of the dilution gas pipe and is diluted The exhaust gas flow path after measuring the concentration of the previous exhaust gas and connected to the dilution gas pipe is connected to the blower via the activated carbon tower as the exhaust gas decomposition tower, and the exhaust gas decomposition tower As a catalyst tower A three-way valve forming a second flow path connected to the blower, and the control unit sets the input set value by the input operation means as a gas concentration regulation value for atmospheric discharge, and the input set value and dilution When the measured gas concentration reaches a first predetermined value less than the calculated value calculated from the magnification, an alarm is instructed, and the control unit sets the input set value by the input operation means of the activated carbon tower. When the measured gas concentration reaches a second predetermined value that is less than a calculated value calculated from the input set value and the dilution rate, the second concentration from the first flow path is set as the ignition concentration value at which activated carbon ignites. The three-way valve is instructed to switch to this flow path.

  In addition, an activated carbon tower that decomposes exhaust gas that is controlled to be released into the atmosphere with activated carbon, a blower that discharges the gas decomposed in the activated carbon tower to the atmosphere, and non-removable gases such as air and nitrogen on the upstream side of the blower A dilution gas pipe that communicates with the exhaust gas flow path, a gas concentration meter that measures the exhaust gas concentration provided in the exhaust gas flow path, a measured value from the gas concentration meter, and an input set value from the input operation means A control unit for instructing a gas concentration alarm based on the exhaust gas processing method. The ignition concentration value at which activated carbon ignites is input in advance, then the gas concentration measured by the gas concentration meter is input, and calculated from the measured gas concentration and the exhaust gas decomposition ability by the activated carbon. When it is determined that the converted gas concentration value has reached a predetermined value less than the ignition concentration value, it is instructed to shut off the exhaust gas input to the activated carbon tower, and the measured gas concentration value is An exhaust gas processing method for instructing an alarm when it is determined that a predetermined value less than a calculated value calculated from a gas concentration restriction value and a dilution factor of atmospheric release is reached.

  According to the present invention, in an exhaust ozone treatment apparatus using activated carbon and / or a catalyst, the concentration and flow rate of a processing gas (gas after exhausted ozone treatment with activated carbon or the like) before dilution with air or the like, and dilution of air or the like Based on the ozone concentration of the diluted gas predicted from the measured value or experimental value of the gas flow, the alarm is sent, the inflow of the exhaust gas is interrupted, the gas flow path is switched, etc., and the concentration of exhaust ozone is kept below the specified value. Can be reduced. Thus, since it measures before dilution with air etc., the sensitivity of an ozone densitometer may be low, and, thereby, an installation cost can be reduced and economical efficiency can be improved.

  An exhaust gas treatment apparatus according to an embodiment of the present invention will be described in detail below with reference to FIGS. FIG. 1 is a process diagram showing the overall configuration of the exhaust gas treatment apparatus according to the first embodiment of the present invention. FIG. 2 is a flowchart showing the processing method of the exhaust gas processing apparatus according to the first embodiment. FIG. 3 is a process diagram showing the overall configuration of the exhaust gas treatment apparatus according to the second embodiment of the present invention. FIG. 4 is a flowchart showing a processing method of the exhaust gas processing apparatus according to the second embodiment.

  FIG. 5 is a process diagram showing the overall configuration of the exhaust gas treatment apparatus according to the third embodiment of the present invention. FIG. 6 is a flowchart showing a processing method of the exhaust gas processing apparatus according to the third embodiment. FIG. 7 shows processing steps showing a modification of the overall configuration of the exhaust gas processing apparatus according to the third embodiment. FIG. 8 shows processing steps showing the overall configuration of the exhaust gas processing apparatus according to the fourth embodiment of the present invention. FIG. 9 is a flowchart showing a processing method of the exhaust gas processing apparatus according to the fourth embodiment.

  In the drawings, 1 is exhaust gas, 2 is a flow path, 3 is an ozone concentration meter, 4 is an activated carbon tower, 5 is a flow path, 6 is a blower, 7 is a control device, 8 is an input means, 9 is an alarm device, and 10 is exhaust gas. Source control device, 11 is a branch channel, 12 is a three-way valve, 13 is a channel, 14 is a catalyst tower, 15 is a channel, 16 is a flow meter, 17 is a branch channel, 18 is a flow meter, 19 is a flow rate Each represents a regulating valve.

“First Embodiment”
First, in the embodiment of the present invention, the case where the object of removal of exhaust gas treatment is ozone contained in the exhaust gas will be described as an example. However, ozone is not limited to ozone, and as a gas to be treated with activated carbon and / or a catalyst, ozone is used. In addition to these, dioxins and odorous gases are listed, and these gases are regulated gases that are regulated so that they cannot be released into the atmosphere as they are, and the present invention can also be applied to these gases.

  In the exhaust ozone treatment process shown in FIG. 1, the exhaust gas 1 passes through the flow path 2 and flows into the activated carbon tower 4. In the activated carbon tower 4, ozone contained in the exhaust gas 1 is decomposed by the filled activated carbon. Thereafter, the exhaust gas 1 flows out into the flow path 5 as a processing gas (the gas after the ozone in the exhaust gas is decomposed by activated carbon or the like is referred to as a processing gas), and a part of it flows into the ozone concentration meter 3 to reduce the ozone concentration. After being measured, merge again. Subsequently, after being diluted with air or non-ozone gas such as nitrogen injected from the branch channel 11 connected to the channel 5, it is discharged into the atmosphere by the blower 6.

  The control device 7 is connected to an ozone concentration meter 3, an input unit 8, an alarm device 9, and an exhaust gas generation source control device (a control device for a device that performs disinfection or deodorization using ozone) 10. The control device 7 compares the measured value C of the ozone concentration received from the ozone concentration meter 3 with the alarm transmission value CA received from the input means 8, and sends a signal to the alarm device 9 if the measured value C is higher. An alarm is transmitted from the alarm device 9. Here, the alarm transmission value CA is a value set by the input means 8, and for example, it may be set to a value corresponding to an appropriate value of less than 0.06 ppm which is a regulated value of photochemical oxidant (the alarm transmission value CA is This is a value that is compared with the measured value of the ozone concentration meter 3, and is a value before dilution corresponding to an appropriate value less than the above-mentioned regulation value).

  Further, the control device 7 compares the upper limit value CH (CH> CA) set by the input means 8 with the measured value C, and sends a signal to the exhaust gas generation source control device 10 when the measured value C is higher. The exhaust gas generation source control device 10 blocks the inflow of exhaust gas into the flow path 2. The upper limit value CH may be set to a value corresponding to an appropriate value less than the value at which the ozone concentration at the inlet of the activated carbon tower 4 reaches the ignition concentration of the activated carbon (the upper limit value CH corresponds to the measured value of the ozone concentration meter 3). And a value before decomposition corresponding to an appropriate value less than the ignition concentration).

  The alarm transmission value CA is set to a value lower than the upper limit value CH, and may be set using the following equation 1, for example.

CA = Ce (F1 + F2) / F1 (Equation 1)
In Equation 1, CA is the alarm transmission value, Ce is the ozone concentration released into the atmosphere, F1 is the flow rate of the exhaust gas 1, and F2 is the flow rate of the non-ozone gas in the branch flow path 11. F1 and F2 may be provided with a flow meter in the flow path 2 and the branch flow path 11, and the measured value may be acquired by the control means 7, or a predetermined value measured in advance at the time of design may be used. F1 and F2 may be predetermined values that are defined in advance at the time of design and have been measured. As will be described later, in the example of FIG. 1, the dilution gas piping is opened to the atmosphere, and the suction capacity of the blower 6, the diameter of the exhaust gas piping and the dilution gas piping, and the pressure loss of the exhaust gas piping are used. It is predetermined. Here, (F1 + F2) / F1 represents a dilution rate. The alarm transmission value CA is set by the input means 8 based on the dilution factor and Ce. Here, the fact that an alarm is issued plays a role of notifying the worker that the gas concentration is high in comparison with the atmospheric emission regulation value and urging the replacement of the activated carbon in the activated carbon tower.

  Furthermore, when the flow control valve 19 is provided in the branch flow path 11 and an alarm is transmitted from the alarm device 9, the opening degree of the flow control valve 19 may be increased to increase the dilution factor. This opening degree adjustment may be automatically performed by the control means 7 connected to the flow rate adjusting valve 19 or manually by an operator who has received an alarm.

  Thus, in the present embodiment, the diverging branch channel 11 for diluting the ozone concentration is arranged on the downstream side of the exhaust gas at the site where the ozone concentration is measured, and the concentration measured by the ozone concentration meter 3 is Since it is before dilution, it is thicker than the ozone concentration released into the atmosphere, and a highly sensitive concentration meter is not required for the measurement. Further, according to the system diagram of the treatment process shown in FIG. 1, using the ozone decomposing capability of the activated carbon tower 4 and the measured value of the ozone concentration meter on the downstream side of the activated carbon tower 4, The ozone concentration can be predicted experimentally.

  Therefore, based on the converted value of the ozone concentration of the exhaust gas flowing into the activated carbon tower 4 (the value of the input means 8 is set based on the converted value), an alarm can be transmitted by comparing with the alarm transmission value CA. In addition, by comparing with the upper limit value CH, it is possible to avoid ignition of the activated carbon by blocking the inflow of the exhaust gas, and to improve the operation reliability. Further, since no catalyst is used, the operating cost of the heating heater for the catalyst and the equipment cost of the catalyst tower are not required, and the economy can be improved.

  1, the ozone concentration measured by the ozone concentration meter 3 (the ozone concentration of the processing gas in the flow path 5) is the flow path on the upstream side of the activated carbon tower 4 as described above. The ozone concentration of the exhaust gas 1 in 2 can be predicted and made compatible, and an alarm value and an upper limit value may be set for the ozone concentration of the exhaust gas 1 as a target. If it does so, the warning of the ignition avoidance of activated carbon and the action | operation of exhaust gas input inhibition can be performed. Depending on various conditions (for example, the decomposition ability of activated carbon, the degree of dilution), generally speaking, when the ozone concentration in the exhaust gas 1 rises, it first reaches the regulation value for the atmospheric release of ozone, and then the ignition of the activated carbon. The concentration will be reached. Depending on the conditions, the time when the regulation value and the ignition concentration are reached may be reversed.

  According to the flowchart of the control device 7 shown in FIG. 2, first, in step S1, the input means 8 receives the value set with the atmospheric emission alarm transmission value CA and its upper limit CH, and in step S2, the ozone concentration meter 3 is received. In step S3, C and CH are compared, and if C <CH, the process proceeds to step S5. When C <CA is not satisfied in step S5, an alarm is issued in step S6, and control is performed to increase the opening degree of the flow regulating valve 19 as appropriate in step S7. If the answer is NO in step S3, a signal is sent to the exhaust gas generation source control device 10 to block the inflow of the exhaust gas 1.

“Second Embodiment”
An exhaust gas treatment apparatus according to a second embodiment of the present invention will be described below with reference to FIGS. FIG. 3 shows processing steps relating to the second embodiment, and FIG. 4 shows the processing method.

  As shown in FIG. 3, the exhaust gas 1 flows into the flow path 2, and a part thereof flows into the ozone concentration meter 3 connected in parallel with the flow path 2 to measure the ozone concentration, and then merges again. After this merging, a branch passage 11 of non-ozone gas (for example, air) for dilution is connected.

  The exhaust gas 1 diluted with a non-ozone gas such as air flows into the activated carbon tower 4 in principle, depending on the ozone concentration. In the activated carbon tower 4, ozone contained in the exhaust gas 1 is decomposed by the filled activated carbon. Thereafter, the exhaust gas 1 flows out to the flow path 5 and is released into the atmosphere by the blower 6.

  The control device 7 is connected to the ozone concentration meter 3, input means 8, alarm device 9, and exhaust gas generation source control device 10. The control device 7 compares the measured value C of the ozone concentration received from the ozone concentration meter 3 with the alarm transmission value CA received from the input means 8, and sends a signal to the alarm device 9 if the measured value C is higher. An alarm is transmitted from the alarm device 9. Further, the control device 7 compares the measured value C with the upper limit value CH received from the input means 8 and, if the measured value C is higher, sends a signal to the exhaust gas generation source control device 10 to control the exhaust gas generation source. The apparatus 10 blocks the flow of exhaust gas into the flow path 2.

  Further, the control means 7 compares the target value CL received from the input means 8 with the measured value C. If the measured value C is lower, the three-way valve 12 provided in the flow path on the inlet side of the activated carbon tower 4. To switch the three-way valve 12 to the flow path 13 side. As a result, the exhaust gas 1 does not pass through the activated carbon tower 4 and flows into the blower 6. At this time, the target value CL, which is a signal for switching the three-way valve 12, is appropriately low in concentration so that the ozone concentration of the exhaust gas 1 after dilution does not need to be decomposed in the activated carbon tower 4 and may be released into the air as it is in the blower 6. (CL <CA), for example, an appropriate value of 0.06 ppm or less as a reference value for photochemical oxidants in the atmosphere. Here, the branch channel 11 does not forcibly push in air or the like that is non-ozone gas, but a fixed amount is sucked into the channel 2 depending on the suction force of the blower 6 and the diameter of the branch channel. (Note that this suction-in configuration can also be applied in the first embodiment). Here, the target value CL is set to an appropriate value (CH> CA> CL) that is lower than a predetermined value (reference value for transmitting an alarm) that is less than the regulation value (0.06 ppm) of atmospheric emission.

  Thus, since the dilution flow rate by air etc. is constant, based on the ozone concentration measured value by the ozone densitometer 3 and the constant dilution flow rate, the target converted into the ozone concentration that is released into the atmosphere as it is without decomposing ozone. The value CL can be set.

  In FIG. 4, the processing method from step S1 to S6 is the same as that in FIG. 2 showing the first embodiment. If the ozone concentration measurement value C is smaller than the target value CL in step S8, the processing method is step S9. The three-way valve 12 is switched so that the exhaust gas flows through the flow path 13 directly connected to the blower 6 instead of via the activated carbon tower 4.

  As described above, according to the second embodiment, the ozone concentration is measured on the upstream side of dilution with a non-ozone gas such as air, and based on this measurement value, installed after the branch flow path for dilution, Uses a three-way valve configuration that switches between connection via the activated carbon tower and direct connection to the blower, and issues an alarm based on the measured ozone concentration on the upstream side of the branch flow path, or shuts off the exhaust gas flow By doing so, ignition of the activated carbon can be avoided and the reliability of operation can be improved. Further, since no catalyst is used, the operating cost of the heating heater for the catalyst and the equipment cost of the catalyst tower are not required, and the economy can be improved.

  Furthermore, when the measured value of ozone concentration at the exhaust gas inlet of the activated carbon tower is below the target value, the exhaust gas consumption is delayed by switching the gas flow path and sending the diluted exhaust gas directly to the blower. Maintenance costs can be reduced.

“Third Embodiment”
An exhaust gas treatment apparatus according to a third embodiment of the present invention will be described below with reference to FIGS. FIG. 5 shows the processing steps relating to the third embodiment, and FIG. 6 shows the processing method. The third embodiment of the present invention is characterized in that a catalyst tower packed with an ozonolysis catalyst is employed only when the measured ozone concentration is high.

  As shown in FIG. 5, the exhaust gas 1 flows into the flow path 2, and a part thereof flows into the ozone concentration meter 3 connected in parallel with the flow path 2 to measure the ozone concentration, and then merges again. After this merging, a branch passage 11 of non-ozone gas (for example, air) for dilution is connected.

  The exhaust gas 1 diluted with a non-ozone gas such as air flows into the activated carbon tower 4 under normal operating conditions, depending on the measured ozone concentration. In the activated carbon tower 4, ozone contained in the exhaust gas 1 is decomposed by the filled activated carbon. Thereafter, the exhaust gas 1 flows out to the flow path 5 and is released into the atmosphere by the blower 6.

  According to FIG. 5, the diluted gas flows into the three-way valve 12, one of the outputs of the three-way valve 12 flows to the activated carbon tower 4, and the other of the outputs flows to the catalyst tower 14 through the flow path 13. The switching of the three-way valve 12 is performed by the control device 7 and is selected according to the magnitude of the ozone concentration measured by the ozone concentration meter 3 as described later.

  The control device 7 is connected to the ozone concentration meter 3, the input means 8, and the alarm device 9. The control device 7 compares the measured value C of the ozone concentration received from the ozone concentration meter 3 with the alarm transmission value CA received from the input means 8, and sends a signal to the alarm device 9 if the measured value C is higher. Then, an alarm is transmitted from the alarm device 9 to urge the operator to pay attention to the ozone concentration. Furthermore, the control device 7 compares the upper limit value CH received from the input means 8 with the measured value C. If the measured value C is higher, the control device 7 goes to the three-way valve 12 provided in the inlet-side flow path of the activated carbon tower 4. A signal is sent and the three-way valve 12 is switched to the flow path 13 side. Here, the upper limit value CH may be a value obtained by adding a safety likelihood to the concentration at which the activated carbon ignites.

  A catalyst tower 14 filled with a catalyst for decomposing ozone is connected to the flow path 13, and ozone contained in the exhaust gas 1 flowing into the catalyst tower 14 is decomposed. Thereafter, the exhaust gas 1 flows out to the flow path 15 connected to the catalyst tower 14 and is released into the atmosphere by the blower 6. Here, the catalyst tower 14 has a higher ozonolysis capability than that of the activated carbon tower 4.

  In FIG. 6, the processing method up to steps S1, S2, S3, S5, and S6 is the same as that in FIG. 4 showing the second embodiment, and the ozone concentration measurement value C is larger than the upper limit value CH in step S3. If there is, the flow path of the three-way valve 12 is switched in step S9, and the exhaust gas is caused to flow to the catalyst tower 14.

  FIG. 7 shows a modification of the exhaust gas treatment apparatus according to the third embodiment of the present invention, in which a flow path 15 through which the exhaust gas 1 flows out from the catalyst tower 14 is connected to the inlet of the activated carbon tower 4. In the case of this modification, an effect of further removing low concentration ozone that could not be decomposed by the catalyst tower 14 using the activated carbon tower 4 can be expected.

  According to the third embodiment, the ozone concentration is measured on the upstream side of dilution with non-ozone gas such as air, and the activated carbon tower and the catalyst installed after the branch flow path for dilution are measured based on the measured value. Adopts a configuration that switches a three-way valve connected to the tower, and issues an alarm based on the measured value of the ozone concentration on the upstream side of the dilution branch flow path, or the ozone concentration at the exhaust gas inlet of the activated carbon tower If the ignition concentration is higher than the ignition concentration of activated carbon, by switching the gas flow path and sending the exhaust gas to the catalyst tower, ignition of the activated carbon can be avoided without stopping the processing of the exhaust gas, and the stability and reliability of operation can be improved. Further, since the catalyst is used only when the ozone concentration in the exhaust gas is high, the catalyst device can be miniaturized and the replacement frequency can be reduced, so that the economy can be improved.

“Fourth Embodiment”
An exhaust gas treatment apparatus according to a fourth embodiment of the present invention will be described below with reference to FIGS. 8 and 9. FIG. 8 shows the processing steps related to the fourth embodiment, and FIG. 9 shows the processing method. In the fourth embodiment of the present invention, when the removal target of the exhaust gas treatment is ozone contained in the exhaust gas, assuming that the ozone concentration is low, the exhaust ozone treatment is performed only by dilution of air or the like, that is, activated carbon The waste ozone treatment is performed without using a tower and a catalyst tower.

  As shown in FIG. 8, after the exhaust gas 1 flows into the flow path 2 and a part of it flows into the ozone concentration meter 3 connected in parallel to the flow path 2 and the ozone concentration is measured, The inflow is measured. Subsequently, the exhaust gas 1 is diluted with a non-ozone gas such as air injected from the branch flow path 17 connected to the flow path 2 and then released into the atmosphere by the blower 6. At this time, the flow rate of the non-ozone gas is measured by the flow meter 18 connected to the branch flow path 17 and then passes through the flow rate adjustment valve 19.

  The control device 7 is connected to the ozone concentration meter 3, input means 8, alarm device 9, flow meter 16, flow meter 18, and flow rate adjustment valve 19. The control device 7 compares the measured value C of the ozone concentration received from the ozone concentration meter 3 with the alarm transmission value CA received from the input means 8, and sends a signal to the alarm device 9 if the measured value C is higher. An alarm is transmitted from the alarm device 9.

  Further, the control device 7 uses the measured value C of the ozone concentration meter 3, the measured value F1 of the flow meter 16, and the measured value F2 of the flow meter 18 (see step S2 in FIG. The concentration Ce of ozone gas released into the inside is calculated (see step S3 in FIG. 9).

Ce = C × F1 / (F1 + F2) (Equation 2)
The control means 7 compares the target concentration Ce1 received from the input means 8 (see step S1 in FIG. 9) with the calculated Ce (see step S4 in FIG. 9), so that F2 satisfies Ce <Ce1. Then, a signal is sent to the flow rate adjusting valve 19 to change the opening of the valve (see step S5 in FIG. 9). Here, the target concentration Ce1 may be set to a reference value of 0.06 ppm for photochemical oxidant in the atmosphere, for example. Further, the flow rate adjusting valve 19 may be manually implemented in response to an alarm from the alarm device 9. Further, as the measurement value F1 of the flow meter 16, a measurement value grasped in advance during design may be used. Further, the measurement value F2 of the flow meter 18 may use the relationship between the opening degree of the flow rate adjustment valve 19 and F2, which is grasped in advance at the time of design.

  According to the fourth embodiment, it is an exhaust gas treatment device that assumes a case where the ozone concentration in the exhaust gas 1 is relatively low. The present invention is applicable to exhaust gas, and here, the flow rate of exhaust ozone gas such as air is actively controlled (a feeding system that pushes air or the like into the branch flow path 17 is used). In this way, by issuing an alarm based on the ozone concentration measured on the upstream side of the branch flow path for dilution, or by changing the dilution factor, no catalyst or activated carbon is required, and the regulation value of exhaust gas is achieved. And economic efficiency can be improved.

It is a processing process figure which shows the whole structure of the waste gas processing apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the processing method of the waste gas processing apparatus which concerns on 1st Embodiment. It is a process drawing which shows the whole structure of the waste gas processing apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the processing method of the waste gas processing apparatus which concerns on 2nd Embodiment. It is a process drawing which shows the whole structure of the waste gas processing apparatus which concerns on the 3rd Embodiment of this invention. It is a flowchart which shows the processing method of the waste gas processing apparatus which concerns on 3rd Embodiment. It is a process process which shows the modification in the whole structure of the waste gas processing apparatus which concerns on 3rd Embodiment. It is a process process which shows the whole structure of the waste gas processing apparatus which concerns on the 4th Embodiment of this invention. It is a flowchart which shows the processing method of the waste gas processing apparatus which concerns on 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exhaust gas 2 Flow path 3 Ozone concentration meter 4 Activated carbon tower 5 Flow path 6 Blower 7 Control apparatus 8 Input means 9 Alarm apparatus 10 Exhaust gas generation source control apparatus 11 Branch flow path 12 Three-way valve 13 Flow path 14 Catalyst tower 15 Flow path 16 Flow rate Total 17 Branch flow path 18 Flow meter 19 Flow control valve

Claims (9)

Exhaust gas decomposition tower that decomposes exhaust gas regulated to be released into the atmosphere with activated carbon and / or a catalyst, a blower that discharges gas decomposed in the exhaust gas decomposition tower to the atmosphere, and air, nitrogen, etc. on the upstream side of the blower From a dilution gas pipe that communicates a non-removal target gas to the exhaust gas flow path, a gas concentration meter that measures the exhaust gas concentration provided in the exhaust gas flow path, a measured value from the gas concentration meter, and input operation means A control unit for instructing a gas concentration alarm based on the input set value of
The gas concentration meter is disposed in the flow path of the exhaust gas after the decomposition treatment in which the exhaust gas is decomposed in the exhaust gas decomposition tower, and is disposed on the upstream side of the dilution gas pipe, and the concentration of the exhaust gas before dilution is determined. Measure and
The control unit uses the input set value by the input operation means as a gas concentration regulation value for atmospheric release, and the measured gas concentration reaches a predetermined value less than a calculated value calculated from the input set value and a dilution rate. Then, an exhaust gas treatment device that issues an alarm. In claim 1,
A flow rate adjustment valve is provided in the dilution gas pipe,
The control unit instructs the alarm, and increases the dilution rate by increasing the opening of the flow rate adjusting valve. In claim 1,
An activated carbon tower is installed as the exhaust gas decomposition tower,
The control unit sets the input set value by the input operation means as an ignition concentration value at which the activated carbon of the activated carbon tower ignites, and the converted gas concentration value calculated from the measured gas concentration and the exhaust gas decomposition ability of the activated carbon An exhaust gas treatment apparatus characterized by instructing to shut off the exhaust gas input to the activated carbon tower when a predetermined value less than the ignition concentration value is reached. Exhaust gas decomposition tower that decomposes exhaust gas regulated to be released into the atmosphere with activated carbon and / or a catalyst, a blower that discharges gas decomposed in the exhaust gas decomposition tower to the atmosphere, and air, nitrogen, etc. on the upstream side of the blower From a dilution gas pipe that communicates a non-removal target gas to the exhaust gas flow path, a gas concentration meter that measures the exhaust gas concentration provided in the exhaust gas flow path, a measured value from the gas concentration meter, and input operation means A control unit for instructing a gas concentration alarm based on the input set value of
The gas concentration meter is arranged on the upstream side of the dilution gas pipe to measure the concentration of exhaust gas before dilution,
A three-way valve that forms a first flow path connected to the blower via the exhaust gas decomposition tower and a second flow path directly connected to the blower in the flow path of the exhaust gas after the dilution gas pipe is connected. Is provided,
The control unit sets the input set value by the input operation means as a gas concentration restriction value for atmospheric emission, and measures the measured gas to a first predetermined value less than a calculated value calculated from the input set value and a dilution rate. When the concentration reaches, it instructs the three-way valve to switch from the second flow path to the first flow path,
Further, the control unit instructs an alarm when the measured gas concentration reaches a second predetermined value less than a calculated value calculated from the input set value and the dilution rate. In claim 4,
An activated carbon tower is installed as the exhaust gas decomposition tower,
The control unit sets the input set value by the input operation means as an ignition concentration value at which the activated carbon of the activated carbon tower ignites, and a third predetermined value less than a calculated value calculated from the input set value and the dilution rate, When the measured gas concentration reaches, an instruction is given to shut off the exhaust gas input to the exhaust gas treatment device. Exhaust gas decomposition tower that decomposes exhaust gas regulated to be released into the atmosphere with activated carbon and / or a catalyst, a blower that discharges gas decomposed in the exhaust gas decomposition tower to the atmosphere, and air, nitrogen, etc. on the upstream side of the blower From a dilution gas pipe that communicates a non-removal target gas to the exhaust gas flow path, a gas concentration meter that measures the exhaust gas concentration provided in the exhaust gas flow path, a measured value from the gas concentration meter, and input operation means A control unit for instructing a gas concentration alarm based on the input set value of
The gas concentration meter is arranged on the upstream side of the dilution gas pipe to measure the concentration of exhaust gas before dilution,
The exhaust gas flow path after the dilution gas pipe connection is connected to the first flow path connected to the blower via the activated carbon tower as the exhaust gas decomposition tower and the catalyst tower as the exhaust gas decomposition tower. A three-way valve is provided that forms a second flow path leading to the blower,
The control unit sets the input set value by the input operation means as a gas concentration restriction value for atmospheric emission, and measures the measured gas to a first predetermined value less than a calculated value calculated from the input set value and a dilution rate. When the concentration reaches, an alarm is given,
Further, the control unit sets the input set value by the input operation means as an ignition concentration value at which the activated carbon of the activated carbon tower ignites, and a second predetermined value less than a calculated value calculated from the input set value and the dilution factor. In addition, when the measured gas concentration reaches, the three-way valve is instructed to switch from the first flow path to the second flow path. In claim 6,
Instead of the second flow path connected to the blower via the catalyst tower as the exhaust gas decomposition tower, a flow path connected in order of the three-way valve, the catalyst tower inlet, the catalyst tower outlet, and the activated carbon tower inlet is formed. An exhaust gas treatment apparatus characterized by that. A first flow path for exhaust gas that is restricted from being released into the atmosphere, and a second flow path for the non-regulated gas that joins the first flow path to dilute the exhaust gas with a non-regulated gas such as air or nitrogen. A flow path, a blower that discharges gas containing exhaust gas from the merged third flow path to the atmosphere, and a gas concentration that measures the exhaust gas concentration provided in the first flow path on the upstream side of the blower An exhaust gas treatment apparatus comprising: a meter; and a control unit that instructs a gas concentration alarm based on a measured value from the gas concentration meter and an input set value from an input operation unit,
The gas concentration meter is disposed on the upstream side of the confluence at the second flow path, and measures the concentration of exhaust gas before dilution,
The first flow path is provided with a first flow meter for measuring the flow rate of the exhaust gas, and the second flow path is provided with a second flow meter and a flow rate adjusting valve for measuring the flow rate of the non-regulated gas. Provided,
The control unit calculates a dilution rate based on outputs from the first flow meter and the second flow meter, and is released to the atmosphere based on the dilution rate and the measured value of the gas concentration meter. Calculate the gas concentration,
Further, the control unit sets the input set value by the input operation means as a gas concentration regulation value for atmospheric emission, and gives an alarm when the calculated gas concentration reaches the input set value. An exhaust gas treatment apparatus characterized by increasing the dilution rate by increasing the opening. Activated carbon tower for decomposing exhaust gas restricted to atmospheric release with activated carbon, a blower for releasing the gas decomposed in the activated carbon tower to the atmosphere, and non-removable target gases such as air and nitrogen on the upstream side of the blower Based on the dilution gas piping communicating with the exhaust gas flow path, the gas concentration meter for measuring the exhaust gas concentration provided in the exhaust gas flow path, the measured value from the gas concentration meter and the input set value from the input operation means A control unit for instructing a gas concentration alarm, and a processing method for processing exhaust gas,
From the input operation means, the control unit is preliminarily input with a gas concentration regulation value of atmospheric emission and an ignition concentration value at which activated carbon in the activated carbon tower ignites, and subsequently, the gas concentration measured by the gas concentration meter Is entered,
When it is determined that the converted gas concentration value calculated from the measured gas concentration and the exhaust gas decomposition ability by the activated carbon has reached a predetermined value less than the ignition concentration value, the exhaust gas input to the activated carbon tower is shut off. Is instructed to
Further, an alarm is instructed when it is determined that the measured gas concentration value has reached a predetermined value less than a calculated value calculated from the atmospheric gas concentration restriction value and the dilution factor. Exhaust gas treatment method.

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