JP6275666B2 - Thermal storage type combustion deodorization apparatus and its operation method - Google Patents

Description

  The present invention relates to a regenerative combustion deodorization apparatus that burns exhaust gas containing volatile organic compounds (hereinafter referred to as “VOC”) and discharges purified gas from which VOC has been removed to the atmosphere, and its It relates to the operation method.

Exhaust gas containing VOCs such as toluene (C ₆ H ₅ CH ₃ ), xylene (C ₈ H ₁₀ ), etc. from automobile paint factories, metal washing, printing factories, adhesive / adhesive paper manufacturing factories, etc. Occur. Since exhaust gas containing VOC cannot be discharged directly into the atmosphere from the viewpoint of pollution prevention, it must be detoxified and discharged into the atmosphere.

  Conventionally, main methods for treating exhaust gas containing VOC (hereinafter referred to as “treated gas”) include a combustion method, an adsorption method, an ozone oxidation method, a microbial decomposition method, and the like. Among these, especially for VOCs such as toluene and xylenes, the combustion method is optimal from the viewpoint of cost and processing efficiency.

  The combustion method further includes a direct combustion method, a catalytic combustion method, a heat storage combustion method, and the like. Among them, the regenerative thermal oxidizer (RTO) is widely used in the above-mentioned factories because the regenerative combustion method has the advantage that the heat recovery efficiency is 85% or more. Thermal storage type combustion deodorization apparatuses include a three-column type (multi-column type) disclosed in Patent Documents 1 and 2 and a two-column type disclosed in Patent Document 3. In the following description, a three-column heat storage type combustion deodorization apparatus 1 'will be described as an example.

  As shown in FIG. 3, the regenerative combustion deodorizer 1 ′ includes a combustion chamber 3 having a burner 2, and three heat storage chambers (5 </ b> A, 5 </ b> B) respectively communicating with the combustion chamber 3 and incorporating a heat storage body 4. , 5C) and the fan 6, the gas to be processed 7 that supplies the gas to be processed supplied from the gas supply source to be processed (not shown) to any one of the heat storage chambers, for example, 5A, to the combustion chamber 3. (Processed gas supply flow path) and a processed gas exhaust pipe 8 (processed gas exhaust) for exhausting the processed gas that has been subjected to thermal decomposition (oxidative decomposition) in the combustion chamber 3 through another heat storage chamber, for example, 5B And a purge gas extraction pipe 9 (purge gas flow) for returning to the upstream side of the fan 6 through a heat storage chamber, for example, 5C, through which the gas to be treated has passed in the previous step, using a part of the treated gas after completion of combustion as purge gas. Road).

  The gas supply pipe 7 to be processed is provided with first on-off valves 10A, 10B, 10C. Second on-off valves 11A, 11B, and 11C are interposed in the treated gas exhaust pipe 8. The purge gas extraction pipe 9 is provided with third on-off valves 12A, 12B, 12C. The purge gas extraction pipe 9 is provided with a control valve 13 whose valve opening is adjusted so that the flow rate of the purge gas is constant. Further, a gas supply valve 15 to be processed is provided on the upstream side of the merging point between the gas supply flow path 14 to be processed connected to the suction side of the fan 6 and the purge gas extraction pipe 9.

  Next, operation of the above-described regenerative combustion deodorizer 1 ′ will be described with reference to FIGS. In the following description, toluene will be described as an example of VOC. First, the gas to be processed supplied from the gas supply source to be processed (not shown) is introduced to the suction side of the fan 6 through the gas supply valve 15 to be processed. And the to-be-processed gas supplied from the fan 6 is supplied from the to-be-processed gas supply pipe 7 to the heat storage chamber, for example, 5A, in which heat is stored in the previous process among the three heat storage chambers 5A, 5B, 5C. Preheated by heat exchange with the heat storage body 4 of the heat storage chamber 5A and introduced into the combustion chamber 3 (processed gas supply step).

Subsequently, toluene (C ₆ H ₅ CH ₃ ) in the gas to be treated is carbon dioxide (CO ₂ ) by a combustion reaction with oxygen (O ₂ ) contained in the gas to be treated in the combustion chamber 3 as shown in the following equation. ) And water (H ₂ O), for example, to a treated gas of about 800 ° C. As shown in FIG. 4A, surplus oxygen remaining from the oxidative decomposition reaction remains in the treated gas. In FIG. 4 (a), the upper side from the dotted line shows the component in the gas to be processed, and the lower side shows the component in the processed gas. In addition, these are for explanatory purposes, and the width of the frame showing each has nothing to do with the ratio of the gas component to be contained.

[Equation 1]
C ₆ H ₅ CH ₃ + 9O ₂ → 7CO ₂ + 4H ₂ O

  Thereafter, the high-temperature treated gas is cooled by heat exchange with the gas to be treated in the previous step, passes through a heat storage chamber, for example, 5B, in which a purge step described later is completed, and exchanges heat with the heat storage body 4 in the heat storage chamber 5B. Then, the temperature of the heat storage body 4 is lowered to 100 ° C. to 150 ° C. while being heated to about 800 ° C., and then diffused into the atmosphere from the processed gas exhaust pipe 8 (processed gas exhaust process).

  Further, a part of the processed gas generated in the combustion chamber 3 is supplied as a purge gas to the heat storage chamber through which the gas to be processed has passed in the previous step, for example, the 5 C heat storage body 4, and remains inside the heat storage body 4. After removing the processing gas containing the organic compound, the purge gas is circulated through the purge gas extraction pipe 9 to the processing gas introduction flow path 14 (purge process).

  Then, the first on-off valves 10A, 10B, 10C, the second on-off valves 11A, 11B, 11C, and the third on-off valves 12A, 12B, 12C are switched every predetermined time. That is, when a predetermined time (for example, 1 minute) elapses, the first on-off valve 10A, the second on-off valve 11B, and the third on-off valve 12C are closed from the open, the first on-off valve 10B, the second on-off valve 11C, 3 The on-off valve 12A is opened from the closed state, and the gas to be processed is supplied from the gas to be processed supply pipe 7 to the heat storage body 4 of the heat storage chamber 5B heated by the processed gas in the previous process, and heat exchange with the heat storage body 4 is performed. After being preheated, heat decomposition (oxidative decomposition) is performed in the combustion chamber 3, and the processed gas passes through the second open / close valve 11 </ b> C and the processed gas exhaust pipe 8 from the heat storage chamber 5 </ b> C purged in the previous step. Discharged inside. The remaining first on-off valve 10C, second on-off valve 11A, and third on-off valve 12B are kept closed.

  On the other hand, a part of the processed gas generated in the combustion chamber 3 is supplied to the heat storage chamber 5A as a purge gas. The purge gas removes the gas to be treated including the organic compound remaining in the heat storage body 4 of the heat storage body 5A when the first on-off valve 10A is closed from the open state, and then the third on-off valve 12A and the purge gas extraction pipe 9 are removed. And is recirculated to the gas introduction flow path 14 to be processed. In this way, the heat storage chamber 5B is a gas to be processed supply process, the heat storage chamber 5C is a processed gas exhaust process, and the heat storage chamber 5A is a purge process. Subsequently, after a predetermined time elapses, the respective on-off valves are switched, and the gas storage process 5C is performed in the heat storage chamber 5C, the gas exhaust process processed in the heat storage chamber 5A, and the purge process is performed in the second heat storage chamber 5B. As described above, during operation of the regenerative combustion deodorization apparatus 1 ′, the operation of sequentially switching the gas to be treated process, the treated gas exhaust process, and the purge process between the heat storage chambers 5A, 5B, and 5C every predetermined time. Continue for a predetermined time.

JP 2011-102664 A Japanese Patent Laid-Open No. 10-47636 JP 2001-324121 A

  By the way, the gas to be processed includes, for example, a gas to be processed in which VOC generated from a printing factory is mixed with air, or a gas to be processed having a very high VOC concentration exhausted from a raw material tank or a product tank of a chemical factory, for example. . In recent years, there is an increasing demand for purifying the latter gas to be treated with a regenerative combustion deodorizer. The gas to be processed having a very high VOC concentration is usually stored in the tank in a state where the tank is purged with an inert gas such as nitrogen gas from the viewpoint of preventing explosion.

  Here, the purification process of the above-described gas to be treated using the conventional heat storage type combustion deodorization apparatus 1 ′ shown in FIG. 3 will be examined below. The conventional regenerative combustion deodorization apparatus 1 'has a configuration for purifying a gas to be treated in which VOC is mixed with air as shown in FIG. 4 (a). On the other hand, as shown in FIG. 4B, the gas to be treated having a very high VOC concentration exhausted from the raw material tank or product tank of the chemical factory contains almost no oxygen for safety (strictly speaking, Although a trace amount of oxygen is considered to remain, it is illustrated as being zero in FIG. 4B). Actually, in addition to the gas to be processed containing a small amount of oxygen as described above, there is also a gas to be processed made of a high concentration VOC that does not contain any oxygen. When such a gas to be treated is supplied into the combustion chamber 3 of the regenerative combustion deodorizing apparatus 1 ′, oxygen remaining in the combustion chamber 3 (excess oxygen after the burner 2 burns) is the gas to be treated. The combustion reaction does not proceed sufficiently, and there is a problem that the treated gas containing VOC is released to the atmosphere.

  Therefore, the present invention provides a regenerative combustion deodorization capable of completely purifying a gas to be treated containing a high concentration VOC and a gas to be treated containing a very small amount of oxygen, or a gas to be treated comprising a high concentration VOC containing no oxygen at all. An object is to provide an apparatus and an operation method thereof.

The regenerative combustion deodorization apparatus of the present invention includes a combustion chamber provided with a burner, at least two heat storage chambers each communicating with the combustion chamber, each having a heat storage body, and a target supplied from a fluid supply source. A gas to be treated that is supplied to the combustion chamber by passing the processing gas through the heat storage chamber that has been stored in the previous step in the heat storage chamber, preheated by heat exchange with the heat storage body of the heat storage chamber, and The treated gas pyrolyzed in the combustion chamber is passed through the heat storage chamber of the heat storage chamber which has been cooled by heat exchange with the gas to be processed in the previous step, and the temperature is lowered by heat exchange with the heat storage body of the heat storage chamber. In the regenerative combustion deodorization apparatus, the treated gas exhaust passage for exhausting the exhaust gas and the flow path switching mechanism for sequentially switching the supply of the gas to be treated and the exhaust of the treated gas between the heat storage chambers. Spent gas An oxygen concentration measuring means for measuring a residual oxygen concentration in the treated gas, and an oxidizing gas supply means for supplying an oxidizing gas for accelerating combustion of the gas to be treated into the combustion chamber. And based on a comparison result between a residual oxygen concentration in the treated gas measured by the oxygen concentration measuring means and a predetermined reference value, the oxidizing property is adjusted so that the residual oxygen concentration is within the reference value. Control means for controlling the gas supply means, and the oxidizing gas supply means is provided corresponding to each of the heat storage chambers, and the control means is provided with the gas to be treated supplied to the combustion chamber. The oxidizing gas supply means provided on the heat storage chamber side that is executing the process gas supply step is controlled . In addition, in this invention, the heat storage chamber which has arrange | positioned the heat storage body does not intend only each independent space enclosed by the wall, but the space (at least divided into two or more by the structure of the heat storage body itself ( Gas flow path).

  Instead of the oxygen concentration measuring means, a VOC concentration measuring means for measuring the VOC concentration in the processed gas may be provided.

  It is preferable that the oxidizing gas is supplied to an upper space of the heat storage body arranged in a heat storage chamber in which a gas to be processed is supplied to the combustion chamber.

  The oxidizing gas supply means is connected to the gas supply flow path of each heat storage chamber, and the oxidizing gas is supplied into the gas supply flow path of the heat storage chamber performing the gas supply process. Also good.

  The oxidizing gas is preferably combustion air supplied from the combustion air supply path of the burner via the burner.

Further, the operation method of the heat storage type combustion deodorization apparatus is supplied from a fluid supply source, a combustion chamber provided with a burner, at least two heat storage chambers each communicating with the combustion chamber, and each having a heat storage body disposed therein. A gas to be treated that is preheated by heat exchange with the heat storage body of the heat storage chamber, and is supplied to the combustion chamber. By passing the processed gas that has been thermally decomposed in the combustion chamber through the heat storage chamber that has been cooled down by heat exchange with the gas to be processed in the previous step in the heat storage chamber, and by heat exchange with the heat storage body of the heat storage chamber the processed gas exhaust passage for exhausting by cooling, supply of the gas to be treated between the individual heat storage chambers, and sequentially switching the flow path switching mechanism to exhaust the processed gas, provided corresponding to the respective heat storage chambers is, the object to be processed And an oxidizing gas supply means for supplying an oxidizing gas for promoting the combustion of gas into the combustion chamber, wherein the oxygen concentration measuring means Measuring the residual oxygen concentration of the gas, comparing the residual oxygen concentration in the treated gas measured in the step with a predetermined reference value, and based on the comparison result in the step, A step of controlling the supply of the oxidizing gas by the oxidizing gas supply means so that the oxygen concentration is within the reference value; and a process gas supply step in which the gas to be processed is supplied to the combustion chamber. Controlling the oxidizing gas supply means provided on the heat storage chamber side .

  Instead of the step of measuring the residual oxygen concentration in the treated gas by the oxygen concentration measuring means, a step of measuring the VOC concentration in the treated gas by the VOC concentration measuring means may be included.

  According to the present invention, a regenerative combustion deodorization that can be completely purified by oxidizing and decomposing a gas to be treated containing a high concentration VOC and a small amount of oxygen, or a gas to be treated consisting of a high concentration VOC containing no oxygen at all. A device and a method for operating the device can be provided.

It is a schematic block diagram of the thermal storage type combustion deodorizing apparatus which concerns on embodiment of this invention. It is a schematic block diagram which shows the modification of the thermal storage type combustion deodorizing apparatus which concerns on embodiment of this invention. It is a schematic block diagram of the conventional heat storage type combustion deodorizing apparatus. (A) is a schematic diagram showing an oxidative decomposition reaction of a gas to be treated in which VOC (toluene) is mixed with air, and (b) is a gas to be treated containing a high concentration of VOC treated with a conventional heat storage combustion deodorizer. (C) is a schematic diagram explaining this invention which can purify the to-be-processed gas containing a high concentration VOC.

  Hereinafter, a heat storage type combustion deodorization apparatus and an operation method thereof according to embodiments of the present invention will be described with reference to the accompanying drawings. Note that the following description is merely an example of one embodiment of the present invention, and is not intended to limit the present invention, its application, or its use.

  In this specification, the “oxidizing gas” is a gas that can oxidatively decompose VOC in the processing gas into carbon dioxide and water, and oxygen-enriched air, pure oxygen gas, or the like can be used. It is preferable to use air that is abundant in the atmosphere. In the following description of the embodiment, the oxidizing gas is described as “auxiliary air”.

  FIG. 1 shows a schematic configuration of a regenerative combustion deodorizer 1 according to the present embodiment. This regenerative combustion deodorization apparatus 1 is heated by a combustion chamber 3 that heats a gas to be treated by a burner 2 and thermally decomposes (oxidizes and decomposes) VOC contained in the gas to be treated. It is provided with three heat storage chambers 5A, 5B, and 5C in which a heat storage body 4 that transfers heat to and from the gas to be treated is accommodated, and is configured as a so-called three-column heat storage type combustion deodorization apparatus. The regenerative combustion deodorization apparatus 1 communicates with a production process 50 (for example, a raw material tank or a product tank in a chemical factory) via a gas introduction flow path 14 to be processed.

  As shown in the figure, the basic structure of the regenerative combustion deodorization apparatus 1 of the present embodiment is the same as that of the regenerative combustion deodorization apparatus 1 ′ described in FIG. Description is omitted.

  As shown in FIG. 1, the combustion chamber 3 of the regenerative combustion deodorizer 1 is provided with a thermometer 30 that measures the temperature in the combustion chamber 3. The thermometer 30 is electrically connected to a temperature controller (not shown), and the temperature controller (not shown) is electrically connected to the burner 2 (in the drawing, these electrical connections are omitted). . As a result, the burner 2 is turned on / off or turned down based on the deviation between the actually measured value detected by the thermometer 30 and the upper limit / lower limit set values set in advance in a temperature controller (not shown). Is controlled, and the temperature in the combustion chamber 3 is maintained at a predetermined temperature.

  The temperature of the combustion chamber 3 gradually increases with the amount of solvent heat contained in the gas to be treated. If this state continues, the temperature of the combustion chamber 3 further rises, and the heat storage body 4, the treated gas exhaust pipe 8, and the second on-off valves 11A, 11B, 11C may be thermally damaged. For this reason, a hot bypass valve 34 that dissipates a part of the high-temperature combustion gas in the combustion chamber 3 to the atmosphere is provided in the upper part of the combustion chamber 3.

  As shown in the figure, the hot bypass valve 34 is provided in the vicinity of the terminal side 8 ′ of the treated gas exhaust pipe 8 and communicates with the treated gas exhaust pipe 8. The hot bypass valve 34 opens the hot bypass valve 34 when the temperature of the combustion chamber 3 rises to, for example, 880 ° C. or higher due to the amount of solvent heat contained in the gas to be treated. The portion is discharged from the discharge port 32 to the atmosphere through the end side 8 ′ of the treated gas exhaust pipe 8 to prevent the temperature of the combustion chamber 3 from excessively rising.

  Next, the features of the regenerative combustion deodorizer 1 according to the embodiment of the present invention will be described below. As shown in FIG. 1, the regenerative combustion deodorization apparatus 1 is an oxygen concentration meter (oxygen concentration measuring means) for measuring the residual oxygen concentration in the treated gas (synonymous with the residual oxygen concentration in the combustion chamber 3). 40, air supply nozzles (oxidizing gas supply means) 42A, 42B, 42C for supplying auxiliary air (oxidizing gas) necessary for oxidative decomposition of VOC into the combustion chamber 3, and air supply nozzles 42A, 42B , 42 </ b> C has a control unit (control means) 44 that controls the supply of auxiliary air into the combustion chamber 3.

  As the oxygen concentration meter 40, for example, a known zirconia oxygen concentration meter is used. In the embodiment, the oxygen concentration meter 40 is provided in the path of the treated gas exhaust pipe 8. The position where the oxygen concentration meter 40 is provided is preferably on the downstream side of the hot bypass valve 34. By providing at this position, the behavior of the residual oxygen concentration in the combustion chamber 3 (the behavior of the VOC concentration) can also be detected when the hot bypass valve 34 is open, and according to the oxygen concentration of the processed gas that is actually released to the atmosphere. Thus, the supply amount of auxiliary air can be controlled.

  The air supply nozzles 42A, 42B, and 42C are respectively provided through the peripheral wall portions of the heat storage combustion deodorizer 1 corresponding to the heat storage chambers 5A, 5B, and 5C. An air supply pipe 45 is connected to the air supply nozzles 42A, 42B, and 42C, and communicates with an air supply fan 46 provided separately. The supply pipe 45 is provided with on-off valves 48A, 48B, and 48C that can open and close the flow path of the supply pipe 45.

  The auxiliary air supplied into the combustion chamber 3 from any one of the supply nozzles 42A, 42B, and 42C is directly above the heat storage body 4 disposed in each of the heat storage chambers 5A, 5B, and 5C (that is, the heat storage type combustion deodorization). In the process gas supply process of the apparatus 1, the VOC oxidative decomposition reaction can be ensured by supplying the process gas to the upper space immediately after the heat storage body 4 passes through.

  As described in [Problems to be Solved by the Invention], a gas to be processed including a high concentration VOC and a gas to be processed containing a small amount of oxygen, or a gas to be processed consisting of a high concentration VOC containing no oxygen at all is conventionally used. Even if it is supplied into the combustion chamber 3 of the regenerative combustion deodorizer 1, the combustion reaction of the gas to be treated does not proceed sufficiently, and the treated gas containing VOC is released to the atmosphere. For this reason, in the regenerative combustion deodorization apparatus 1 according to the embodiment of the present invention, as shown in FIG. 4 (c), oxygen necessary for the VOC to undergo an oxidative decomposition reaction, that is, auxiliary air is externally supplied to the combustion chamber 3. It has the structure which supplies in. The control unit 44 executes auxiliary air supply control.

  As shown in the figure, the control unit 44 is electrically connected to the oximeter 40 and the on-off valves 48A, 48B, and 48C. The control unit 44 compares a signal indicating the oxygen concentration in the processing gas output from the oxygen concentration meter 40 with a control reference to be described later, and based on the comparison result, the heat storage chambers 5A, 5B, 5C are covered. The valve opening degree of the on-off valves 48A, 48B, and 48C corresponding to any one of the air supply nozzles 42A, 42B, and 42C disposed on the side of any one of the heat storage chambers that are executing the processing gas supply process is controlled.

  The control unit 44 mainly includes hardware parts such as a CPU and storage means, and software parts such as a program for controlling the valve opening degree of each of the on-off valves 48A, 48B, and 48C. The control unit 44 is provided with a lower limit value and an upper limit value of the residual oxygen concentration having a preset width above and below the control target value in order to control the residual oxygen concentration in the processed gas within a predetermined concentration range. The reference is stored in advance.

  Specifically, in the control standard, “residual oxygen concentration 5%” is set as the control target value, “residual oxygen concentration 3%” is set as the lower limit value, and “residual oxygen concentration 7%” is set as the upper limit value. Has been. That is, the supply of auxiliary air is controlled so that the residual oxygen concentration in the treated gas falls within the range of 5% ± 2%. The control target value, the lower limit value, and the upper limit value described above are examples, and can be appropriately changed according to the composition of the gas to be treated and the operating conditions of the regenerative combustion deodorizer 1, but the lower limit value is It is preferable to set the value to 3% or more. In addition, although the method of measuring the VOC density | concentration in processed gas and performing supply of auxiliary air after detecting VOC is also considered, VOC will be diffused to air | atmosphere by the time of supplying auxiliary air in this case. For this reason, when measuring the VOC concentration in the treated gas, it is preferable to provide a VOC concentration measurement port in the combustion chamber 3 and sample the VOC. Therefore, in the present embodiment, it is assumed that oxygen remains in the treated gas (portion indicated by X in FIG. 4 (c)) that the VOC has been oxidatively decomposed and the supply of auxiliary air A margin is provided by setting a lower limit value in the control (it has been empirically found that there is a possibility that VOC may remain in the treated gas when the residual oxygen concentration falls below 3%. ). Thus, in this embodiment, VOC is not left in the processed gas.

The control unit 44 executes the following control according to the change in the residual oxygen concentration in the treated gas.
(A) When the indicated value of the oxygen concentration meter 40 falls below, for example, 3% of the lower limit value, the corresponding on-off valve among the on-off valves 48A to 48C is controlled to enter the auxiliary air into the combustion chamber 3 from the corresponding supply nozzle. And the residual oxygen concentration in the treated gas is controlled to fall within the range of 5% ± 2%.
(B) Also, for example, when the residual oxygen concentration in the treated gas falls within a range of 5% ± 2%, or when the indicated value of the oxygen concentration meter 40 exceeds, for example, 7% of the upper limit value, the opening / closing is performed. Of the valves 48A to 48C, the corresponding opening / closing valve is closed to stop the supply of auxiliary air, or the opening amount of the corresponding opening / closing valve is reduced to reduce the supply amount of auxiliary air. Further, the upper limit value is preferably set to 10% or less because the auxiliary air supply pipe 45 and the supply fan 46 are enlarged even if there is a margin like the lower limit value (experienced gas has been treated. If the residual oxygen concentration is 10%, there is no possibility that VOC remains in the treated gas.)

  Since the gas to be treated is a combustible gas, it is preferable to use explosion-proof types for the gas to be treated supply fan 52 and the fan 6.

  Subsequently, the operation of the regenerative combustion deodorization apparatus 1 according to the embodiment of the present invention will be described with reference to FIG. 1 and FIG. Note that this operation example focuses on the process gas supply process and the processed gas exhaust process, and the “purge process” of the regenerative combustion deodorization apparatus 1 is the regenerative combustion deodorization apparatus 1 ′ described in FIG. Therefore, the re-explanation here is omitted. In this operation example, as an example of the gas to be processed, a gas to be processed containing a high concentration VOC and a small amount of oxygen will be described as an example.

  First, it is assumed that the combustion chamber 3 of the regenerative combustion deodorizing apparatus 1 is heated to a predetermined temperature by the burner 2 and the amount of gas to be processed is the rated processing amount of the regenerative combustion deodorizing apparatus 1.

  A gas to be processed which is supplied from a production process 50 (for example, a raw material tank or a product tank of a chemical factory) and contains a high concentration VOC (for example, a high concentration toluene) containing almost no oxygen is a gas to be processed supply fan 52. To the suction side of the fan 6 through the gas supply valve 15 to be processed. And the to-be-processed gas supplied from the fan 6 is supplied from the to-be-processed gas supply pipe 7 to the heat storage chamber, for example, 5A, in which heat is stored in the previous process among the three heat storage chambers 5A, 5B, 5C. Preheated by heat exchange with the heat storage body 4 of the heat storage chamber 5 </ b> A and introduced into the combustion chamber 3.

  Then, the oxygen concentration meter 40 measures the residual oxygen concentration in the treated gas that has been treated in the combustion chamber 3 and exhausted from the heat storage chamber 5 </ b> B to the treated gas exhaust pipe 8. Here, when the indicated value of the oxygen concentration meter 40 is lower than 3% which is the lower limit value of the control reference, the control unit 44 controls, for example, the on-off valve 48A among the on-off valves 48A to 48C to supply the air supply nozzle. Auxiliary air is supplied into the combustion chamber 3 from 42A.

  The high-concentration VOC in the gas to be processed introduced into the combustion chamber 3 in the above-mentioned gas supply process by supplying auxiliary air is oxidatively decomposed into carbon dioxide and water in the combustion chamber 3 and processed at, for example, 800 ° C. It becomes gas (see FIG. 4C).

  Thereafter, the high-temperature processing gas is cooled by heat exchange with the gas to be processed in the previous process, passes through the heat storage chamber, for example, 5B, in which the purge process is completed, exchanges heat with the heat storage body 4 of the heat storage chamber 5B, and stores the heat. The temperature of the body 4 is lowered to 100 ° C. to 150 ° C. while being heated to about 800 ° C., and then released from the treated gas exhaust pipe 8 to the atmosphere. At that time, if the residual oxygen concentration in the treated gas is measured by the oxygen concentration meter 40 and the residual oxygen concentration in the treated gas is within the range of 5% ± 2% of the control reference, the control unit 44 Then, the corresponding on-off valves among the on-off valves 48A to 48C are closed to stop the supply of auxiliary air. Or the control which reduces the supply amount of auxiliary air by restricting the valve opening degree of a corresponding on-off valve is executed. In addition, if the indicated value of the oximeter 40 exceeds 7%, which is the upper limit value of the control reference, the control unit 44 closes the corresponding on / off valve among the on / off valves 48A to 48C and supplies auxiliary air. To stop. Thereafter, the above-described auxiliary air supply control is performed every time the process gas supply process is switched.

  As described above, the regenerative combustion deodorization apparatus 1 according to the embodiment of the present invention is for the purpose of subjecting a gas to be treated containing high-concentration VOC containing almost no oxygen to combustion treatment (oxidative decomposition). Auxiliary air (that is, oxygen necessary for the VOC to undergo an oxidative decomposition reaction) is supplied from the outside into the combustion chamber 3. Thereby, the to-be-processed gas containing the high concentration VOC can be completely purified. Further, an oxygen concentration meter 40 (or a VOC analyzer) is provided in the treated gas exhaust pipe 8 to measure the residual oxygen concentration (that is, the concentration of VOC) in the treated gas, and the residual oxygen concentration is, for example, 5% ± 2 The supply of auxiliary air is controlled so as to be within the range of%. For this reason, even if the concentration of the VOC fluctuates, the auxiliary air can be supplied following the concentration change, and the oxidative decomposition of the VOC can be ensured.

  In addition, the regenerative combustion deodorization apparatus 1 according to the embodiment of the present invention directly inputs auxiliary air necessary for the oxidative decomposition of VOCs into the combustion chamber 3 of the regenerative combustion deodorization apparatus 1, so Compared with the configuration in which the gas is mixed (diluted gas to be treated in the atmosphere) and then introduced into the regenerative combustion deodorizer 1, the capacity of the fan 6 can be reduced without increasing the size of the entire facility, and the initial cost and running cost can be reduced. Can be reduced.

  Further, since the auxiliary air is supplied to the upper space of any one of the heat storage chambers 5A, 5B, and 5C that is performing the process gas supply process, the auxiliary air is supplied to the entire combustion chamber 3. Compared with the form, the promotion of the oxidative decomposition reaction of VOC is ensured.

  In the heat storage type combustion deodorization apparatus 1 according to the embodiment of the present invention described above, the supply nozzles 42A, 42B, 42C are provided through the peripheral wall portion of the heat storage type combustion deodorization apparatus 1 corresponding to the heat storage chambers 5A, 5B, 5C. In the above embodiment, the auxiliary air is supplied from the supply nozzles 42A, 42B, and 42C into the combustion chamber 3 of the regenerative combustion deodorizer 1. However, the present invention is not limited to such a configuration. For example, the supply nozzles 42A, 42B, 42C are deleted, and the end of the supply pipe 45 (the downstream end in the flow direction of the supply pipe 45) is connected to the first on-off valves 10A, 10B, 10C in the gas supply pipe 7 to be processed. Auxiliary air may be supplied by connecting to the downstream side.

  Further, as shown in FIG. 2, combustion air supplied from the combustion air supply source 22 of the burner 2 via the combustion air supply path 24 using the burner 2 instead of the supply nozzles 42A, 42B, 42C. Can also be supplied into the combustion chamber 3 as auxiliary air. That is, in the case of this modification, in the process gas supply process of the regenerative combustion deodorizer 1, the temperature in the combustion chamber 3 is raised to a predetermined temperature and the burner 2 is not operating. 42A, 42B, and 42C, and the combustion air supply source 22 of the burner 2 can be diverted as an auxiliary air supply source, and the control unit 44 is provided to control the valve openings of the on-off valves 20A to 20C. The apparatus of the heat storage type combustion deodorizing apparatus 1 can be used. In addition, when normal temperature auxiliary air is supplied into the combustion chamber 3, if the temperature maintenance in the combustion chamber 3 is affected, a means for preheating the auxiliary air may be separately provided.

  In the present embodiment, the oxygen concentration meter 40 is provided in the path of the processed gas exhaust pipe 8 to measure the residual oxygen concentration in the processed gas. However, the present invention is not limited to this, and the oxygen concentration meter 40 is used instead. A VOC analyzer may be provided to measure the VOC concentration in the treated gas and supply auxiliary air into the combustion chamber 3. In the present embodiment, an oxygen concentration meter 40 (or VOC analyzer) is provided in the route of the treated gas exhaust pipe 8 to measure the residual oxygen concentration in the treated gas (that is, the concentration of VOC). Although exemplified, the present invention can also be implemented in the form of sampling the gas after the VOC is oxidatively decomposed by providing an oxygen concentration measurement port in the combustion chamber 3 instead of the route of the treated gas exhaust pipe 8.

  In the present embodiment, a gas to be processed containing a high concentration VOC and a very small amount of oxygen, or a gas to be processed consisting of a high concentration VOC containing no oxygen at all is subjected to combustion treatment (oxidative decomposition). It is desirable to supply a purge gas to the heat storage body 4 through which the gas to be processed has passed and to remove the gas to be processed including the organic compound remaining in the heat storage body. However, the purge mechanism itself is an essential configuration. Absent.

  In the present embodiment, a three-column heat storage type combustion deodorization apparatus has been described as an example. However, the present invention is not limited to this, and a two-column type heat storage type having two heat storage chambers. It can also be applied to a combustion deodorization apparatus. In addition, as in the present embodiment, it is not always necessary to provide a plurality of on-off valves for each heat storage chamber. For example, from a plurality of heat storage chambers to a desired heat storage chamber with one rotary switching valve (distribution valve). The present invention can also be applied to a rotation switching valve type regenerative combustion deodorization device that switches connections. In the present embodiment, as an example of the gas to be processed, “a gas to be processed containing a high concentration VOC and a small amount of oxygen” or “a gas to be processed consisting of a high concentration VOC that does not contain any oxygen” is used. Illustrated. In the present invention, in addition to the above-mentioned gas to be processed that cannot be self-combusted, for example, the gas to be processed containing carbon monoxide for some reason, or even if burned, the residual oxygen concentration in the processed gas is less than 3%. Even such a gas to be treated can be subjected to combustion treatment (oxidative decomposition).

  DESCRIPTION OF SYMBOLS 1 Thermal storage combustion deodorizing device, 2 burner, 3 combustion chamber, 4 thermal storage body, 5A-5C thermal storage chamber, 6 fan, 7 to-be-processed gas supply pipe, 8 processed gas exhaust pipe, 8 '(processed gas exhaust pipe 8 ) Terminal side, 9 Purge gas extraction pipe, 14 Processed gas introduction flow path, 20A-20C on-off valve, 22 Combustion air supply source, 24 Combustion air supply path, 40 Oxygen concentration meter (oxygen concentration measurement means), 42A ˜42C Air supply nozzle (oxidizing gas supply means), 44 Control unit (control means), 45 Air supply pipe, 46 Air supply fan, 48A to 48C Open / close valve (part of oxidizing gas supply means)

Claims (7)

A combustion chamber with a burner;
And at least two or more heat storage chambers each communicating with the combustion chamber and each having a heat storage body disposed therein;
A gas to be treated supplied from a fluid supply source is passed through the heat storage chamber of the heat storage chamber where heat is stored in the previous step, preheated by heat exchange with the heat storage body of the heat storage chamber, and supplied to the combustion chamber. A processing gas supply channel;
The treated gas that has been thermally decomposed in the combustion chamber is passed through the heat storage chamber that has been cooled by heat exchange with the gas to be treated in the previous step in the heat storage chamber, and the temperature is decreased by heat exchange with the heat storage body of the heat storage chamber. A treated gas exhaust passage for exhausting
In the regenerative combustion deodorization apparatus comprising a flow path switching mechanism for sequentially switching between supply of the gas to be treated and exhaust of the treated gas between the heat storage chambers,
An oxygen concentration measuring means provided in the treated gas exhaust passage for measuring a residual oxygen concentration in the treated gas;
An oxidizing gas supply means for supplying an oxidizing gas for accelerating combustion of the gas to be treated into the combustion chamber;
Based on the comparison result between the residual oxygen concentration in the treated gas measured by the oxygen concentration measuring means and a predetermined reference value, the oxidizing gas supply is performed so that the residual oxygen concentration is within the reference value. Control means for controlling the means ,
The oxidizing gas supply means is provided corresponding to each of the heat storage chambers,
The control means controls the oxidizing gas supply means provided on the side of the heat storage chamber that is executing the process gas supply process in which the gas to be processed is supplied to the combustion chamber. Deodorizing device.   The regenerative combustion deodorization apparatus according to claim 1, further comprising a VOC concentration measuring unit that measures a VOC concentration in the treated gas instead of the oxygen concentration measuring unit. The said oxidizing gas is supplied to the upper space of the said thermal storage body arrange | positioned in the thermal storage chamber which is performing the to-be-processed gas supply process by which the said to-be-processed gas is supplied to the said combustion chamber. 2. The regenerative combustion deodorization apparatus according to 2. The oxidant gas supply means is connected to the gas supply flow path of each heat storage chamber, and the oxidant gas is supplied into the gas supply flow path of the heat storage chamber performing the gas supply process. The regenerative combustion deodorizer according to claim 1 or 2. The regenerative combustion deodorization apparatus according to claim 1 or 2, wherein the oxidizing gas is combustion air supplied from a combustion air supply path of the burner via the burner. A combustion chamber with a burner;
And at least two or more heat storage chambers each communicating with the combustion chamber and each having a heat storage body disposed therein;
A gas to be treated supplied from a fluid supply source is passed through the heat storage chamber of the heat storage chamber where heat is stored in the previous step, preheated by heat exchange with the heat storage body of the heat storage chamber, and supplied to the combustion chamber. A processing gas supply channel;
The treated gas that has been thermally decomposed in the combustion chamber is passed through the heat storage chamber that has been cooled by heat exchange with the gas to be treated in the previous step in the heat storage chamber, and the temperature is decreased by heat exchange with the heat storage body of the heat storage chamber. A treated gas exhaust passage for exhausting
A flow path switching mechanism for sequentially switching between supply of the gas to be processed and exhaust of the processed gas between the heat storage chambers;
An operation method of a regenerative combustion deodorization apparatus provided corresponding to each heat storage chamber and provided with an oxidizing gas supply means for supplying an oxidizing gas for promoting combustion of the gas to be treated into the combustion chamber. There,
Measuring the residual oxygen concentration in the treated gas by the oxygen concentration measuring means;
Comparing the residual oxygen concentration in the treated gas measured in the step with a predetermined reference value;
Controlling the supply of the oxidizing gas by the oxidizing gas supply means so that the residual oxygen concentration is within the reference value based on the comparison result in the step;
And a step of controlling the oxidizing gas supply means provided on the side of the heat storage chamber that is performing the process gas supply step in which the gas to be processed is supplied to the combustion chamber. The heat storage type according to claim 6, further comprising a step of measuring a VOC concentration in the treated gas by a VOC concentration measuring means instead of a step of measuring a residual oxygen concentration in the treated gas by the oxygen concentration measuring means. Operation method of combustion deodorization device.

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