JPH0538417A - Apparatus for heating and cleaning harmful gas - Google Patents

Abstract

PURPOSE:To provide an apparatus for heating and cleaning a harmful gas in which harmful components including carbon monooxide (CO) and hydrocarbons (HC) in various kinds of exhaust gases are heated and eliminated by oxidation at a low level of energy loss and at a high cleaning efficiency. CONSTITUTION:The gas inlet and outlet 1, 8 at the ends of the main body 5 of an apparatus for heating and cleaning a harmful gas are interchanged every given time by a damper 9 to reverse the gas flow direction 7 in the main body of the apparatus. In the apparatus including a heater 4 at the middle, a catalyst layer 3, and heat accumulator layers 2 fixed respectively on the way of gas passages from each end to the middle, an exhaust gas is introduced by a fan 22 placed on the exhaust side apart from the main body of the apparatus. A damper 21a fixed at an opening 21 for the introduction of outside air is opened just before the reversion of the gas flow direction. The outside air is introduced into the main body of the apparatus by the fan 22 so that the discharge of an uncleaned exhaust gas is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a harmful gas heating and purification device, and in particular, it heats malodorous and harmful components such as CO (carbon monoxide) and HC (hydrocarbons) mixed in various exhaust gases to an appropriate temperature. The present invention relates to a harmful gas heating / purification device for oxidative purification.

[0002]

2. Description of the Related Art In recent years, it has become indispensable to purify and discharge CO and HC components generated in various combustors, drying and heat treatment due to their harmfulness and odor. C
As a method of purifying O and HC components, a method of heating exhaust gas itself and reacting it with oxygen in gas has the highest purification efficiency and high reliability. Here, in order to raise the temperature of the exhaust gas and allow oxygen in the air to react with CO and HC, a temperature of 800 to 900 ° C. or higher is required, but 200 to 4 in the method using the oxidation catalyst.
The reaction can proceed in the temperature range of 00 ° C. and waste of thermal energy can be eliminated.

A conventional harmful gas purifying apparatus will be described below. FIG. 3 is a catalyst purification device of Conventional Example 1. Figure 3
In FIG. 1, (a) shows the main body of the catalyst purifying device, and (b) shows the system including the heat exchanger. 10 is the main body of the catalyst purifier,
16 is a heat exchanger, 12 is a heating device, and 13 is a catalyst.
In (a), the exhaust gas is introduced into the main body of the catalyst heating device from the inlet 11, heated to a predetermined temperature by the heating device 12, CO, HC and the like are oxidized and purified by the catalyst 13, and discharged from the outlet 14. At this time, the energy required to raise the temperature of the exhaust gas is discharged together with the gas. A system using a heat exchanger for the purpose of recovering a part of this energy is (b). In this case, the exhaust gas introduced from the gas inlet 17 and heated by the heat exchanger 16 flows along the arrow 15 and proceeds to the catalyst purifying apparatus main body 10. The gas purified here enters the heat exchanger 16 again, is cooled, and is discharged from the gas outlet 18. That is, part of the energy required to raise the temperature of the exhaust gas is recovered to reduce energy loss.

On the other hand, FIG. 4 shows a heating and purifying apparatus of the conventional example 2 using a heat storage body, in which the state of (a) and the state of (b) are alternately repeated to reduce heat energy. Is. In FIG. 4, 2 is a heat storage body containing a catalyst, and 4 is a heating device. Reference numeral 9 denotes a damper that controls the flow of harmful exhaust gas. In (a), the exhaust gas is the gas inlet 1
From 9 as shown by arrow 7, gas enters into the purifier through the inlet / outlet 1. After passing through the lower heat storage body 2, it is heated and purified by the heating device 4, is deprived of heat by the upper heat storage body 2, is cooled, is discharged from the gas inlet / outlet 8 and proceeds to the gas outlet 20, after a certain time (b). The dampers 9 are operated so as to change the flow of the exhaust gas as described above. That is, the upper heat storage body 2 which has taken heat from the exhaust gas in (a) works to give heat to the exhaust gas, and supplements a part or most of the energy for heating the exhaust gas. That is, heat is circulated in the purifying device body 5 to save energy.

[0005]

However, the heat exchanger 16 used in the configuration of the above-mentioned conventional example 1 (FIG. 3) is usually composed mainly of thin-walled aluminum having good thermal conductivity, and the heat exchange efficiency is high. Is limited to 50-60%,
Also, aluminum cannot be used for exhaust gas containing corrosive gases such as SOx and NOx because aluminum corrodes. In Conventional Example 2 (FIG. 4), a corrosion-resistant heat storage body 2 containing a catalyst
It is possible to eliminate the drawbacks of Conventional Example 1 by using, and it is possible to realize a purification device with high heat exchange efficiency. However, when the gas flow direction is reversed, the gas introduced into the purification device main body 5 from the last inlet is Downstream heat storage body 2 and heating device 4
Before it reaches the heat storage unit 2, it is stagnated in the vicinity of the heat storage body 2 and the gas inlet / outlet 1 on the upstream side, and is discharged from the gas inlet / outlet 8 simultaneously with the reversal of the gas flow direction. That is, a part of the gas is discharged without being purified, and 100% purification was theoretically impossible.

The present invention solves the problems of the heating and purifying device of the above-mentioned conventional example 2, in which exhaust gas containing harmful gas components is exhausted through 100% catalyst layer and heating device. It is also an object of the present invention to provide a toxic gas heating and purifying device that gives an operation.

[0007]

In order to achieve this object, the harmful gas heating and purifying apparatus of the present invention has a structure that includes a gas inlet, a gas outlet, and a heating and purifying apparatus main body. A fan is provided on the outlet side, gas inlets and outlets are provided at both ends of the heating and purifying apparatus main body for alternately reversing the gas flow direction by a damper at regular intervals, and openings for introducing outside air. is there.

[0008]

With this configuration, the harmful gas heating and purifying apparatus of the present invention is such that the exhaust gas introduced from the gas inlet by the fan provided on the gas outlet side is kept at one end (one side Gas is introduced into the main body of the purifier through the heat storage layer, heated and purified by the heating device and the catalyst layer, cooled by the other heat storage layer, and discharged from the other end (the other gas inlet and outlet). After passing through the fan, the gas is discharged from the outlet. After a certain period of time, the flow path from the gas inlet to the gas inlet of the heating and purifying apparatus main body is closed, and at the same time, the damper at the opening for introducing the outside air is opened to suck the outside air into the heating and purifying apparatus main body by the fan. It The amount of outside air sucked at this time may be an amount sufficient for the exhaust gas component finally introduced into the heating and purifying device body to be sent to the catalyst layer and the heating device in the heating and purifying device body. Next, the opening for introducing the outside air is closed, and the dampers installed at both ends of the heat purifying apparatus main body are operated so that the exhaust gas passes through the inside of the heat purifying apparatus main body in the opposite direction. Even in this mode, after a certain period of time, the flow path from the gas inlet to the gas inlet / outlet of the heating / purifying device main body is closed, and at the same time, the damper is operated so that a certain amount of outside air is sucked into the heating / purifying device main body. By repeating this operation, the exhaust gas is heated and cooled by the heat storage layers on both sides of the main body of the heat purifying apparatus exchanging the roles of heat absorption and heat radiation, and then exhausted. Further, even when the flow direction of the exhaust gas is reversed, the exhaust gas is sent to the catalyst layer and the heating device by the outside air, so that it can be purified 100%.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A harmful gas heating and purifying apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 19 is an exhaust gas inlet, 2
0 indicates the outlet of the exhaust gas. 5 is the main body of the heat purifying device, 2
Is a heat storage layer, 4 is a heating device, and 3 is a catalyst layer. Reference numeral 9 denotes a damper for reversing the flow direction of the exhaust gas in the heat purification device. 21 is an opening for introducing outside air, 21a
Indicates the damper. (B) shows a state in which exhaust gas is allowed to flow inside the purifying device in the state of (a) and outside air is introduced into the heating purifying device main body 5 immediately after a lapse of a certain time. The state of (a) will be described. The exhaust gas enters from the gas inlet 19 by the fan 22 as shown by the arrow 7, enters the heating purifying device main body 5 from the gas inlet / outlet 1 and passes through the heat storage layer 2 below and is heated by the heating device 4 and the catalyst layer 3 Purified by. When passing through the upper heat storage layer 2, the heat energy of the exhaust gas is removed and the exhaust gas is cooled and discharged from the gas inlet / outlet 8 toward the gas outlet 20. After a certain period of time, the damper 9 below the purifier is closed to prevent the exhaust gas from flowing into the heat purifier main body 5, and at the same time, the damper 21a of the lower opening 21 in the figure is opened to let the outside air enter the heat purifier main body 5. The state of (b) was introduced. The amount of the outside air introduced is sufficient to drive the exhaust gas component stagnating inside the gas inlet / outlet 1 and the lower heat storage layer 2 to the heating device 4 and the catalyst layer 3. Figure 2 for the next mode
It was shown to. Damper 21 of opening 21 for introducing outside air
It is FIG. 2A that the flow direction of the exhaust gas in the heating and purifying device main body 5 is reversed from that of FIG. 1A by closing a and operating the upper and lower dampers 9. In this state, the exhaust gas is deprived of heat by the upper heat storage layer 2 and purified by the heating device 4 and the catalyst layer 3, and then deprived of heat by the lower heat storage layer 2 and cooled and discharged from the gas outlet 20. It That is, a part or most of the thermal energy for heating the exhaust gas is confined inside the heating and purifying apparatus main body 5 by the two layers of the heat storage layer 2. The state where the damper 21a of the upper opening 21 in the figure is operated so as to introduce the outside air into the heating and purifying apparatus main body 5 after a certain time has elapsed is shown in (b). By this operation, exhaust gas discharged in an unpurified state can be prevented and the efficiency of purification of harmful components can be increased.

[0011]

As is apparent from the above description of the embodiments, according to the harmful gas heating and purifying apparatus of the present invention, both ends of the heating and purifying apparatus main body have dampers to reverse the flow direction of exhaust gas at regular intervals. Has an inlet / outlet for gas to be alternately converted as an inlet or an outlet, a heating device and a pair of catalyst layers are provided in the center through the heating device, and heat purification having a heat storage layer on each outside of the catalyst layer A device that switches the gas outlet and inlet and reverses the flow direction of the exhaust gas so that the thermal energy for heating the exhaust gas in the two heat storage layers can be confined inside the heating purification device body. However, by introducing the outside air so that there is no exhaust gas component that was not purified when the flow direction of the exhaust gas was reversed and was not purified, and the purification efficiency was reduced. Can provide a structure that exhaust gas passes through the heating device and the catalyst layer, it is possible to greatly improve the efficiency of purifying the exhaust gas.

[Brief description of drawings]

FIG. 1 (a) is an explanatory view showing the concept of the configuration of one mode of the harmful gas heating and purifying apparatus of one embodiment of the present invention. (B) (a) Outside air is introduced into the heating and purifying apparatus main body immediately after the mode is finished. Explanatory diagram showing the installed state

FIG. 2 (a) is an explanatory view showing the concept of the configuration of the same mode. (B) An explanatory view showing a state in which outside air is introduced into the heating and purifying apparatus main body immediately after the (a) mode is finished.

FIG. 3 (a) is an explanatory view showing the concept of the configuration of the catalyst purifying apparatus main body of the first conventional example. (B) The concept of the overall configuration of the catalyst purifying system including the heat exchanger in the catalyst purifying apparatus main body of FIG. 3 (a). Explanatory diagram showing

FIG. 4 (a) is an explanatory view showing the concept of the configuration of a catalyst purifying apparatus main body of a second conventional example. FIG. 4 (b) is an explanatory view showing a state in which the flow direction of exhaust gas is reversed from FIG.

[Explanation of symbols] 1,8 Gas inlet / outlet 2 Heat storage layer 3 Catalyst layer 4 Heating device 5 Heating / purifying device main body 7 Gas flow direction 9 Damper 19 Gas inlet 20 Gas outlet 21 Opening 22 Fan

Claims (2)

[Claims] 1. A gas comprising a gas inflow port, a gas outflow port, and a heating / purifying device main body, wherein the dampers are provided at both ends of the heating / purifying device main body so that the flow direction of the gas is reversed at regular intervals to alternate conversion. In the heating and purifying device having the inlet / outlet, the heating device in the center, the pair of catalyst layers via the heating device, and the heat storage layer on the outside of the catalyst layer, the fan provided on the gas outlet side. And a harmful gas heating and purifying apparatus having an opening near the inlet and outlet of the gas for introducing outside air other than exhaust gas into the heating and purifying apparatus main body. 2. When reversing the flow direction of the gas in the main body of the heating and purifying apparatus at regular intervals, the gas flow path on the inlet side is blocked, and at the same time, an opening for introducing outside air is opened to allow a certain amount of outside air to flow. 2. The harmful gas heating and purifying apparatus according to claim 1, wherein after being introduced into the heating and purifying apparatus main body, the gas flow direction is controlled by the operation of the damper to reverse the direction.