JP3448548B2 - How to remove high boiling substances - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching valve and a heat storage chamber that constitute a regenerative deodorizing apparatus, and a dust attached to a pipe communicating with the regenerative deodorizing apparatus. The present invention relates to a method for removing high-boiling substances such as tar. 2. Description of the Related Art Conventionally, for example, an exhaust gas (gas to be treated) containing a high-boiling substance, which is a malodorous component, discharged from a coating and drying furnace is supplied to a regenerative deodorizer because of its high thermal efficiency. It has been deodorized. [0003] This regenerative deodorizing apparatus comprises, for example, a deodorizing furnace main body comprising a plurality of regenerative chambers, a combustion chamber provided with a heating means such as a burner and a heater, and a switching valve device. The gas to be treated from the coating and drying furnace is
On the way, the temperature is lowered in the gas supply pipe to be treated, for example, about 50 ° C.
Then, it passes through the switching valve device, passes through the heat storage chamber heated in the previous step, and then reaches the combustion chamber, where it reaches the combustion chamber, where it is heated to about 820 ° C. by a heating means, for example, a burner, and the high-boiling substance is removed. It burns and is deodorized. On the other hand, when the high-temperature processing gas that has been deodorized as described above passes through another heat storage chamber to which the gas to be processed is not supplied, heat is taken by the heat storage body of the heat storage chamber and the temperature is lowered. Then, the gas is discharged from the gas discharge pipe to the outside of the furnace through the switching valve device. The exhaust of the processing gas is performed by an exhaust fan. [0006] The supply of the gas to be treated to each of the heat storage chambers and the discharge of the gas to be treated are alternately performed by switching the switching valve device at predetermined time intervals by a timer, and the above steps are repeated. Deodorize high boiling substances in the gas to be treated. The switching of the switching valve device is performed as follows.
In addition to the switching by the timer, the switching may be performed every time the temperature of the processing gas at the outlet of the heat storage chamber reaches a predetermined temperature (for example, 100 ° C.). After one day of operation of the coating and drying oven, the burner is stopped, the supply valve of the gas supply pipe is closed, and clean gas (air) containing no high boiling point substance is supplied to the gas supply pipe. As described above, the combustion chamber is supplied to and exhausted from the regenerative deodorizing device via the switching valve device to keep the temperature in the combustion chamber at about 250 ° C. or less, thereby protecting the flame detecting device. Since the high-boiling substances such as tar have a relatively high condensation temperature (about 50 ° C.), the gas to be treated is cooled at the inner surface of the gas supply pipe to be treated, inside the switching valve device, at the inlet of the heat storage chamber, and the like. Condensed and adhered, causing a blockage of the heat storage body and a malfunction of the switching valve device. Therefore, conventionally, a preheater is provided at a predetermined position of a gas supply pipe to be treated so that the gas to be treated does not fall below the condensation temperature of the high boiling point substance even if the gas to be treated is cooled by a switching valve device or the like. Is heated to prevent the high-boiling substances in the gas to be treated from adhering to the above-described locations. [0010] However, in the method of preheating the gas to be treated by the preheater, the gas to be treated must be kept preheated during the operation of the regenerative deodorizer, so that a large amount of fuel must be used. There is a problem of need. By the way, it is known that the high-boiling substance adhering to the switching valve device or the like is repeatedly heated and cooled by the regenerative deodorizing device being repeatedly operated and stopped, and is carbonized and fixed. Moreover, once the high-boiling substance is fixed, it changes to a substance having various vaporization temperatures. Therefore, to completely vaporize and remove the high-boiling substance, the fixed high-boiling substance must be heated to about 500 ° C. However, since there are various ignition temperatures among the high-boiling substances adhered, there is a risk of causing a fire if heated up to 500 ° C at a stretch. It is difficult to heat to 500 ° C. also from the viewpoint of properties. Therefore, as a result of various studies by the present inventors,
If the high-boiling substance is not fixed to the switching valve device or the like by repeated heating and cooling, that is, if it is simply condensed, the vaporization temperature of the high-boiling substance (for example, 250 ° C.) As described above, it has been found that vaporization can be easily performed at a temperature lower than the ignition temperature (for example, 300 ° C.). Therefore, the present invention focuses on the heat remaining in the heat insulating material constituting the combustion chamber and the heat storage body of the heat storage chamber when the operation of the heat storage type deodorizing apparatus is stopped, and utilizes this to separately A regenerative deodorizer that vaporizes and removes high-boiling substances adhering to a switching valve and a regenerator that constitute a regenerative deodorizer and a pipe connected to the regenerative deodorizer without supplying heat. It is an object of the present invention to provide a method for removing a high-boiling substance adhered to water. According to the present invention, in order to achieve the above object, the present invention relates to a treatment target containing a high-boiling substance by switching a switching valve to a plurality of heat storage chambers communicating with a combustion chamber having a heating means. The gas is sequentially supplied, and after the temperature of the gas to be treated is increased by the heat storage body of the heat storage chamber, the gas is supplied to the combustion chamber to perform the combustion deodorization treatment. During the deodorization of the high-boiling substances in the gas to be treated by the regenerative deodorizing device that raises the temperature of the heat storage body by discharging the deodorized treatment gas, the supply of the gas to be treated is stopped, While the heating means is stopped, a predetermined amount of clean gas containing no high-boiling substance is supplied to the combustion chamber, then the supply is stopped, and the temperature of the processing gas from the heat storage chamber at the exit side of the heat-storage chamber is changed to the high-boiling substance. Vaporization temperature Degree, and controls the switching valve so as to be a predetermined temperature equal to or lower than the ignition temperature, and circulates and supplies the processing gas from the heat storage chamber outlet side at the predetermined temperature to the heat storage type deodorizer. High boiling substances are removed. Next, an embodiment of the present invention will be described with reference to the drawings. The figure is a schematic view showing a heat storage type deodorizing facility applied to a method for removing high boiling substances attached to a heat storage type deodorizing apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes a known heat storage type deodorizing device, which comprises a deodorizing furnace main body 2 and a switching valve device 7. The deodorization furnace main body 2 has a combustion chamber 3 having a heating means, for example, a burner 4 at an upper part thereof, and a first heat storage chamber 5 communicating with the combustion chamber 3 and having a heat storage body 6 therein.
A and the second heat storage chamber 5B. The switching valve device 7 includes a first switching valve 8A and a second switching valve 8A.
A first and a second switching valve 8A, 8B.
Are two valve seats 10a, 10b having openings 11 in the center arranged at predetermined intervals in the valve box 9; and the valve seat 10a or 10b is moved up and down between the valve seats 10a, 10b by moving the cylinder 12 forward and backward. Valve body 1 for closing any of 10b
A gas supply pipe P1 for supplying a gas to be treated (exhaust gas) containing a high-boiling substance from a coating / drying furnace (not shown) to the regenerative deodorizing apparatus ₁ is defined by the valve seats 10a and 10b. 1. Upper chambers Ra, Ra of second switching valves 8A, 8B
And the lower chambers Rb and Rb of the first and second switching valves 8A and 8B are provided with a gas exhaust pipe P ₂ provided with an exhaust fan 14.
Is in communication with The middle chambers Rc, Rc of the first and second switching valves 8A, 8B communicate with the chambers Ca, Cb of the first heat storage chamber 5A and the second heat storage chamber 5B, respectively. Further, a gas supply valve V ₁ is provided at a predetermined position of the gas supply pipe P ₁ , and a clean gas supply valve V ₂ is provided downstream thereof. Note that 15
Is an exhaust tower. [0021] Then, the circulation pipe provided with a closing valve V ₃ and the predetermined position and the exhaust fan 14 downstream of the predetermined position of the gas discharge pipe P ₂ of the clean gas supply valve V ₂ downstream of the gas supply pipe P ₁ P They are connected by ₃ and form a circulation path. Next, a method for deodorizing a gas to be treated having a high-boiling substance by the regenerative deodorizer 1 will be described. As shown in FIG. 1, the on-off valve V ₃ is closed,
The valve body 13 of the first switching valve 8A closes the opening 11 of the valve seat 10b,
In a state where the valve body 13 of the second switch valve 8B is closed, respectively the opening 11 of the valve seat 10a, and drives the exhaust fan 14 together with igniting the burner 4, the treated gas supply valve V ₁ open. The gas to be treated having a high boiling point substance flows from the upper chamber Ra of the first switching valve 8A through the middle chamber Rc to the first heat storage chamber 5A.
From A to the combustion chamber 3 where the burner 4 provides about 820
The high-boiling-point substances are burned and deodorized in the combustion chamber 3 maintained at a temperature of 2 ° C., and then the processing gas passes through the second heat storage chamber 5B, during which it exchanges heat with the heat storage body 6 to be cooled, and the second switching valve 8B through the middle chamber Rc, lower chamber Rb, a gas discharge pipe P ₂ exhaust tower 15
Emitted from the atmosphere. When a predetermined time has elapsed, the two cylinders 12 and 12 are operated by a timer (not shown).
That is, in the first switching valve 8A, the opening 1 of the valve seat 10a
1 is closed by the valve body 13 and the valve seat 1 is provided in the second switching valve 8B.
It closes the opening 11 of the 0b in the valve body 13, while supplying the gas to be treated into the second regenerator 5B, to discharge the process gas from the first heat storage chamber 5A to the gas discharge pipe P _2. As described above, when the supply and discharge paths of the gas to be processed and the processing gas are changed, the gas to be processed is supplied to the heat storage unit 6 heated by the passage of the processing gas in the previous process, so that the preheating is performed. , The high temperature (for example, 820 ° C.) processing gas is cooled by the gas to be processed in the previous process.
When passing through, heat is taken away, cooled to 100 to 150 ° C. or lower, and released to the atmosphere. This process is repeated to continuously burn and remove high-boiling substances in the gas to be treated. Next, the switching valve 7 and the heat storage chamber 5A constituting the regenerative deodorizing apparatus 1, 5B, and, a method for removing the high boiling point substance adhering to the regenerative deodorizing device a gas supply pipe P ₁ which communicates with the 1 Will be described. [0028] When the (case of the batch operation once / day) the painting operation daily drying furnace is finished, closing the gas to be treated supply valve V ₁ stops the burner 4 of the combustion chamber 3, the clean the gas supply valve V ₂ is opened to purge the gas to be treated of supplying clean gas such as air from a gas supply pipe P ₁ gas supply pipe P and in the regenerator 6 _1. In this case, since the inside of the combustion chamber 3 is still at a high temperature, high-boiling substances are burned and deodorized. [0029] Then, the clean gas supply valve V ₂ to the on-off valve V ₃ opened with a closed. Opening and closing valve V ₃ is opened, since the suction force of the exhaust fan 14 is the communicating portion a between the gas discharge pipe P ₂ of the circulation pipe P ₃ is in the act by negative pressure, from the exhaust fan 14 Part of the processing gas is circulation pipe P
₃ to the regenerative deodorizer 1, and thereafter, by repeating this, a circulation path of the processing gas is formed. When the temperature of the processing gas discharged from one of the first and second heat storage chambers 5A and 5B reaches the set temperature in the chambers Ca and Cb of the heat storage chambers 5A and 5B, the switching valve device 7 is switched. Here, the set temperature is equal to or higher than the vaporization temperature of the high boiling substance and equal to or lower than the ignition temperature, for example, 300 ° C.
To As a result, the processing gas having a sufficient amount of heat to vaporize the high-boiling substance circulates through the regenerative deodorizing apparatus 1, and during that time, particularly, the heat storage where the high-boiling substance has adhered during the previous deodorizing treatment. high-boiling materials attached inside the gas supply pipe P ₁ in and switching valve 7 which communicates with the formula deodorizing apparatus 1, or the heat storage chamber is vaporized, and thus is deodorized in the combustion chamber 3. The processing gas circulates through the combustion chamber 3 by heat radiation.
Then, the internal temperature is maintained at about 250 ° C., and thereafter, the exhaust fan 14 is stopped, the on-off valve V ₃ is closed, and the operation of removing high-boiling substances is completed. In the above description, the supply and discharge of the gas to be processed and the processing gas are performed by the switching valve device 7 including the two switching valves 8A and 8B. However, the present invention is not limited to this. Or a rotary valve having a plurality of passages. In the above description, the deodorizing treatment is performed once a day in accordance with the cycle of the batch operation. However, the deodorizing treatment may be performed once every several days depending on the adhesion state of the high boiling point substance. When the deodorizing treatment is performed continuously, the operation of the deodorizing treatment may be temporarily stopped before the high-boiling substance is fixed, and then performed. As is apparent from the above description, according to the present invention, before the high-boiling substance adheres to the low-temperature part, the heat of the regenerative deodorizing device is utilized to utilize the high-boiling substance. A high-boiling substance is vaporized and removed by circulating the processing gas heated to a temperature higher than the vaporization temperature to a low-temperature portion, and does not require a preheater, etc., and has a simple structure and energy saving. . Further, since the vaporized high-boiling substance is burned in a combustion chamber having a temperature equal to or higher than the ignition temperature, the vaporized high-boiling substance is not released to the outside. Further, since the operation of removing the high-boiling substances can be easily performed at the end of the operation of the regenerative deodorizer, the operation time is not wasted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a regenerative deodorizing facility for carrying out the present invention. [Description of Signs] 1-regenerative deodorizer, 3-combustion chamber, 4-heating means, 5A
~ The first regenerator, 5B through the second regenerator, 6 regenerator, 7 switching valve device, 14 an exhaust fan, P ₁ ~ gas supply pipe, P ₂ -
Gas exhaust pipe, P ₃ ~ circulation pipe, V ₁ ~ treated gas supply valve,
V ₂ ~ clean gas supply valve, V ₃ ~ off valve.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-10-47636 (JP, A) JP-A-11-51358 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23G 7/06 103 F23G 7/06 ZAB F23G 5/50 ZAB

Claims (1)

(57) [Claim 1] A gas to be treated containing a high-boiling substance is sequentially supplied to a plurality of heat storage chambers communicating with a combustion chamber having a heating means by switching a switching valve, and the gas to be treated is Is heated by the heat storage body of the heat storage chamber, and then supplied to the combustion chamber to perform combustion deodorization processing, and by discharging the deodorized processing gas from another heat storage chamber to which the gas to be processed is not supplied. In the deodorizing treatment of the high-boiling substance in the gas to be treated by the regenerative deodorizing device which raises the temperature of the heat storage body and discharges the same, the supply of the gas to be treated is stopped, and the heating means is stopped. After a predetermined amount of clean gas containing no is supplied to the combustion chamber, the supply is stopped, and the temperature of the processing gas from the heat storage chamber at the exit side of the heat storage chamber is equal to or higher than the vaporization temperature of the high boiling substance and equal to or lower than the ignition temperature. Of the specified temperature A method for removing high-boiling substances, characterized in that the switching valve is switched and controlled as described above, and the processing gas from the outlet side of the heat storage chamber at the predetermined temperature is circulated and supplied to the regenerative deodorizer.