JP2000297928A - Regenerative combustion type gas treating device and operation method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel regenerative combustion type gas treating device and an operation method therefor to improve combustion efficiency by suppressing useless purge. SOLUTION: At least four or more regenerative type burners formed such that a combustion mode, a purge mode, and an exhaust mode are changed over, in order, in succession are provided in a combustion chamber. A purge mode operation time is further decreased than other mode operation time and setting is effected such that the purge modes of the regenerative burners are prevented from being overlapped with each other. This constitution shortens only a purge time without shortening a combustion mode time and an exhaust mode time, whereby useless purge is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative combustion type gas processing apparatus using a regenerative combustion type burner for recovering exhaust heat of flue gas and improving combustion efficiency, and a method of operating the same.

[0002]

2. Description of the Related Art Conventionally, in the field of industrial furnaces and the like, a so-called regenerative combustion furnace for recovering exhaust heat of combustion exhaust gas to improve combustion efficiency has been used.

[0003] In this regenerative fuel furnace, as shown in FIG. 9 (1), a ceramic honeycomb regenerator 2 is provided in a combustion chamber 1.
And a pair of regenerative combustion burners A and B equipped with the heat storage chambers 3 and 3 of the regenerative combustion burners A and B.
The combustion air line 4 and the exhaust gas line 5 are connected to each other, and either one of the heat storage combustion by the combustion air sent from the combustion air line 4 and the fuel such as the city gas supplied from the fuel injection unit 7 Type burner (hereinafter,
(Abbreviated as a burner) A is used as a burner, and at the same time, the other burner B is stopped to function as an exhaust passage, so that exhaust heat in the combustion exhaust gas generated in the combustion chamber 1 is used as a honeycomb regenerator on the burner B side. After a certain period of time (for example, about 30 seconds) after the collection by (2), FIG.
As shown in (1), the function is instantaneously switched by valves provided in each line, and the combustion air is preheated by the heat storage of the honeycomb-type heat storage body 2, thereby easily improving the combustion efficiency and saving energy. It is.

If a gas containing a bad smell or harmful substance such as ammonia or unburned hydrocarbon is supplied as all or a part of the combustion air supplied to such a regenerative fuel furnace, the heat storage It becomes possible to use the type fuel furnace not only as a simple combustion furnace, but also as a gas processing apparatus capable of decomposing these odors and harmful substances at a high temperature to make them odorless and harmless.

[0005] However, when such a processing gas is used as all or a part of the combustion air, the processing gas accumulated in the heat storage chamber 3 at the time of switching the combustion is undecomposed together with the combustion exhaust gas from the exhaust gas line 5 into the atmosphere. And the surrounding environment is degraded.

Therefore, in order to prevent this, another heat storage combustion type burner C is added to the combustion chamber 1 as shown in FIG.
A purge line 8 is connected to each of B and C, and a part of the combustion exhaust gas flowing through the exhaust gas line 5 is caused to flow to the purge line 8 side, thereby forcing odor gas accumulated in the heat storage chamber 3 into the combustion chamber 1. There has been proposed a gas processing apparatus that performs purging.

That is, as shown in FIG. 10 (1), a certain period of time elapses while the burners A are set to the combustion mode by controlling the valves of the lines 4, 5 and 8 and the burners B are functioning as the exhaust passage. Thereafter, as shown in FIG. 10 (2), the combustion is switched to the burner B side and the burner C
Function as an exhaust passage, the exhaust gas line 5
By purging a part of the combustion exhaust gas flowing through the burner A through the purge line 8, the processing gas accumulated in the heat storage chamber 3 of the burner A is blown out into the combustion chamber 1 and thermally decomposed to be odorless and harmless. After being converted, it is exhausted from the burner C as a combustion exhaust gas. Therefore, after a certain time has elapsed from this state, as shown in FIG. 10 (3), when the combustion is switched to the burner C side and the burner A side is made to function as an exhaust passage, the heat storage chamber 3 Since there is no odor gas, it is possible to avoid the inconvenience that the processing gas accumulated in the heat storage chamber 3 is directly discharged from the exhaust gas line 5 to the atmosphere as described above.

[0008]

However, in such a purge type gas processing apparatus, as shown in FIG. 6, a purge time performed by a burner A, B, or C at regular time intervals. Is the same as the combustion time and the exhaust time, and is overpurged, and the exhaust gas is discharged to the combustion chamber 1.
There is an inconvenience of circulating wastefully inside.

That is, while the amount of the processing gas accumulated in the heat storage chamber 3 is generally very small, the purge time is the same as the combustion time and the exhaust time. Into the combustion chamber 1
As a result, problems such as lowering the temperature inside the combustion chamber 1 and causing insufficient combustion occur.

For this reason, it is conceivable to reduce the purge time by shortening the combustion time and the exhaust time so as to prevent over-purge.
However, there is a problem that the combustion is switched before the heat is sufficiently heated, and a sufficient heat storage effect cannot be obtained.

It is also conceivable to prevent over-purge by shortening only the opening time of the purge valve. However, in this case, the burner is completely functional until the burner is switched to another function. This causes a problem that the functions of the entire apparatus cannot be used effectively.

Further, if this burner is used as an exhaust passage in order to prevent such a non-functional state, the flow rate of the combustion exhaust gas to another burner in which heat is already stored is reduced, so that the burner is not sufficiently used. In addition to not being able to obtain a sufficient heat storage effect, when the combustion mode is further switched, a new problem such as overheating of the heat storage body of the burner occurs.

The present invention has been devised in order to effectively solve such a problem, and its main purpose is to reduce only the purge time without reducing the combustion time and the exhaust time. It is an object of the present invention to provide a novel heat storage combustion type gas processing apparatus capable of preventing wasteful purging and improving combustion efficiency, and an operation method thereof.

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention sequentially switches the combustion mode, the purge mode, and the exhaust mode in order and makes the operation time of the purge mode shorter than the operation time of the other modes. At least four or more heat storage combustion type burners provided on the wall surface of the combustion chamber are provided on the wall surface of the combustion chamber, and at regular time intervals so that the purge modes of these heat storage combustion type burners do not overlap. And control the switching time of each regenerative combustion type burner so that all remaining regenerative combustion type burners are in either the combustion mode or the exhaust mode while one of the regenerative combustion type burners is in the purge mode. This is the driving method that is to be performed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a heat storage combustion type gas processing apparatus according to the present invention.

As shown in the figure, on the wall defining the side surface of the combustion chamber 1, there are six burners A, B, C, D, in which the honeycomb-shaped heat storage body 2 is accommodated in the heat storage chamber 3 as described above.
E and F are provided so as to oppose three by three.

Each of these burners A, B, C, D,
A processing gas line 10 for supplying gas containing malodorous components and harmful substances such as ammonia and unburned hydrocarbons to the combustion chamber 1 and a combustion gas exhaust gas in the combustion chamber 1 are provided to E and F. And a purge gas line 12 for blowing a purge gas are connected to each other.
Further, the processing gas line 10 and the flue gas line 1
1. Each branch of the purge gas line 12 is provided with an electromagnetic valve V for instantaneously controlling the flow of the gas. Further, the flue gas line 11 includes:
A blower 13 for forcibly exhausting the combustion exhaust gas is provided, and further downstream of the blower 13,
A purge gas line 12 is connected so as to be branched therefrom. That is, a part of the combustion exhaust gas flowing into the combustion exhaust gas line 11 is forcibly flown to the purge gas line 12 side by the blower 13 and is used as a part of the purge gas.

Next, an example of an operation method of the regenerative combustion type gas processing apparatus having such a configuration will be described with reference to FIGS. FIG. 2 is a conceptual diagram showing the combustion, exhaust, and purge operation modes for each burner in order.
Fig. 3 shows the combustion, exhaust, and purge operation modes over time for each burner.

As shown in FIG. 2A and FIG. 3, first,
Immediately after the start of operation, two burners A and B are set to the combustion mode, and the other burners D, E, and F are set to the exhaust mode. By this combustion, the processing gas line 10
The processing gas supplied from the odorless and harmful substances such as ammonia and unburned components is thermally decomposed by combustion to become odorless and harmless, and then becomes combustion exhaust gas to burner D, E, F
And discharged from the exhaust gas line 11 into the atmosphere. Further, each heat storage body 2 of the burners D, E, and F is heated with the passage of the combustion exhaust gas, and recovers and stores heat in the combustion exhaust gas. At this time, the remaining burner C
By closing all the electromagnetic valves V, a rest state in which neither mode is performed is set.

Next, after a lapse of a predetermined time in such a state,
For example, in the present embodiment, after about 10 seconds, of the burners A and B in the combustion mode, the burner B
At the same time, only the burner F is ignited to switch from the exhaust mode to the combustion mode (FIG. 2 (2)). Thereby, since the processing gas supplied to the burner F is efficiently preheated by the heat storage body 2 immediately before combustion, excellent combustion efficiency can be exhibited. As shown in the figure, the burner B is instantaneously switched to the purge mode simultaneously with the ignition of the burner F, so that the unprocessed processing gas in the processing gas line 10 reaching the heat storage chamber 3 of the burner B and its electromagnetic valve. Is forcibly sent into the combustion chamber 1 by the purge gas sent from the purge gas line 12, is thermally decomposed, is harmless and odorless, and is exhausted through the burners C, D and E. The switching control of the solenoid valve and the fuel supply / ignition control to each burner are automatically performed as time passes by a control means such as a microcomputer (not shown).

Next, when about 10 seconds have elapsed from such a state, as shown in FIG. 2 (3), the burner A, which has already been in the combustion mode for about 20 seconds, is switched to the purge mode. At the same time, the burner E is switched to the combustion mode. As a result, the remaining odor gas is purged on the burner A side as described above, and the burner E is removed.
On the side, the heat stored in the heat storage body 2 is effectively used.

Further, when about 10 seconds have elapsed from such a state, as shown in FIG. 2 (4), the burner F, which has already been in the combustion mode for about 20 seconds, is switched to the purge mode. By switching the burner D to the combustion mode, the same effect as described above can be obtained. Then, as shown in FIG. 2 (5), after about 10 seconds have elapsed from this state, the burner E is switched to the purge mode, and at the same time, the burner C is switched to the combustion mode. 2 (6)
After the burner D is switched to the purge mode and the burner B is switched to the combustion mode for about 10 seconds as shown in FIG. 2, the mode returns to the mode shown in FIG.
The same mode switching is repeated every second to continue the combustion.

Therefore, according to the operation method of the present invention, as shown in FIG. 3, the purge mode time in each burner is greatly reduced as compared with the combustion mode time, and unnecessary purging is suppressed. As a result, wasteful combustion exhaust gas does not flow into the combustion chamber 1 as described above, and it is possible to suppress deterioration in combustion efficiency due to a decrease in temperature in the combustion chamber 1 and a shortage of combustion air. .
Also, as shown in the figure, the combustion, purge, and exhaust modes are interrupted in any burner, even though the purge mode time is set to be less than half the time of the other modes. The burners are switched continuously in sequence, so that all the burners can be used effectively without wasting the burners unnecessarily except immediately after the start of the operation, and excellent operating efficiency can be exhibited. .

Although the present embodiment has been described with respect to a case where six regenerative combustion burners are provided for one combustion chamber 1, the number of regenerative combustion burners is not limited to six. As described in the claims, the object of the present invention can be achieved if the number of the installations is at least four or more, and the more the number of installations, the shorter the purge mode time. Becomes possible. That is, when four regenerative burners are used, combustion,
A series of modes such as purge and exhaust are divided into four time zones, only one of which is used as a purge mode, and one or two of the remaining three time zones are used as a combustion or exhaust mode. If this is the case, the purge time can be shortened compared to the other modes, and at the same time, all the burners can be used effectively without stopping any of the burners as described above. Further, in the actual machine, the processing gas remaining in the heat storage chamber 3 and the like in each burner is extremely small, and the time required for purging is about 1 to 2 seconds. Therefore, by increasing the number of burners installed in order to further shorten the purge time of each burner, useless purging, that is, the inflow of combustion exhaust gas that adversely affects combustion can be significantly reduced.

Further, in the above-described embodiment, depending on the case where the amount of gas flowing into and out of the combustion chamber 1 is increased or depending on the operation mode, as shown in FIG. The combustion gas is drawn into the opposing burner or the adjacent burner by the flow, and the combustion gas immediately flows out of the combustion chamber 1 (short pass), and the combustion time in the combustion chamber 1 is shortened, and the odor components and the like are sufficiently thermally decomposed. It may be inconvenient that the gas is exhausted together with the exhaust gas before the operation is performed. The first cause is that the size of the combustion chamber 1 is small, but it is also conceivable that the distance between adjacent burners is short and the opposing burners are coaxially arranged.

For this reason, for example, as shown in FIG. 5, partitioning plates 14, 14... Are provided between adjacent burners, or as shown in FIG. If they are arranged obliquely offset from each other, a short path of the combustion flame to the adjacent burner or the opposing burner is prevented, and the combustion time (combustion gas convection time) in the combustion chamber 1 becomes longer. The flowing odor component and the like can be sufficiently burned and decomposed in the combustion chamber 1.

Further, as described above, the apparatus and the operation method of the present invention can exert more excellent effects as the number of burners used increases.
As shown in FIG. 7, if the fuel cells are arranged side by side in the width direction, the size of the combustion chamber 1 also increases in the width direction. Therefore, a large installation space may be required, or the area of the combustion chamber 1 may be increased and thermal efficiency may be reduced. . Therefore, when increasing the number of burners, instead of increasing the number of burners in the horizontal direction, for example, as shown in FIG. 1 is compact and the surface area of the combustion chamber 1 is small.
The combustion efficiency is also improved.

Further, as a processing gas applied to the present invention,
As described above, in addition to gas containing malodorous components and harmful substances such as ammonia and unburned hydrocarbons, combustion exhaust gas discharged from a garbage incinerator or the like, that is, gas containing dioxin is supplied, so that conventional garbage incineration can be performed. Dioxins, which are difficult to remove in furnaces and flue gas treatment facilities, can be reliably decomposed and detoxified at high temperatures.

[0030]

In summary, according to the present invention, only the purge time can be shortened without shortening the time in the combustion mode or the exhaust mode, so that useless purging can be effectively suppressed. As a result, the amount of combustion exhaust gas that has an adverse effect on combustion can be significantly reduced, so that a decrease in the temperature of the combustion chamber and a shortage of combustion air can be prevented, and excellent combustion efficiency can be exhibited. Excellent effects, such as being able to be performed, can be exhibited.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a heat storage combustion type gas processing apparatus according to the present invention.

FIG. 2 is a process chart showing an embodiment of an operation method of a heat storage combustion type gas processing apparatus according to the present invention.

FIG. 3 is a graph showing an embodiment of an operation method of the heat storage combustion type gas processing apparatus according to the present invention.

FIG. 4 is a conceptual diagram showing an influence of a combustion flame in a combustion chamber of the heat storage combustion type gas processing apparatus according to the present invention.

FIG. 5 is a configuration diagram showing another embodiment of the heat storage combustion type gas processing apparatus according to the present invention.

FIG. 6 is a configuration diagram showing another embodiment of the heat storage combustion type gas processing apparatus according to the present invention.

FIG. 7 is a side view showing an example of the arrangement of a regenerative combustion burner in a combustion chamber.

FIG. 8 is a side view showing an example of the arrangement of a regenerative combustion burner in a combustion chamber.

FIG. 9 is an explanatory view showing a conventional regenerative fuel furnace and an operation method thereof.

FIG. 10 is an explanatory view showing a deodorizing apparatus to which a conventional regenerative fuel furnace is applied and an operation method thereof.

FIG. 11 is a graph showing an operation method of a deodorizing apparatus to which a conventional regenerative fuel furnace is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combustion chamber 2 Heat storage body 3 Heat storage type 10 Processing gas line 11 Exhaust gas line 12 Purge gas line 14 Partition plate

Claims (7)

[Claims] 1. A combustion mode in which a processing gas is introduced and burned, a purge mode in which unburned processing gas is purged, and an exhaust mode in which heat is recovered while exhausting the combustion gas are sequentially switched and the purge mode is performed. A regenerative combustion type gas processing apparatus, wherein at least four or more regenerative combustion type burners in which the operation time in one mode is set shorter than the operation time in another mode are provided in a combustion chamber. 2. The regenerative combustion type burners provided on the wall surface are arranged so as to be offset vertically, horizontally, or diagonally so that the combustion flame blowout direction of the opposing regenerative combustion type burners is not coaxial. The heat storage combustion type gas processing apparatus according to claim 1, wherein: 3. The heat storage combustion type gas treatment apparatus according to claim 1, wherein a partition plate is provided between adjacent heat storage combustion type burners provided on the wall surface. 4. The heat storage combustion type gas processing apparatus according to claim 1, wherein each of said heat storage combustion type burners is arranged in upper and lower stages on a wall surface in said combustion chamber. 5. The regenerative combustion type gas processing apparatus according to claim 1, wherein the processing gas is an odor gas containing a malodorous component or a harmful gas containing dioxin. 6. A combustion mode in which a processing gas is introduced and burned, a purge mode in which unburned processing gas is purged, and an exhaust mode in which heat is recovered while exhausting the combustion gas are sequentially switched. At least four or more heat storage combustion burners are provided in the combustion chamber, the operation time of the purge mode is set shorter than the operation time of the other modes, and the purge modes of these heat storage combustion burners are not overlapped with each other. The heat storage combustion burners are shifted at regular intervals so that all the heat storage combustion burners remain in either the combustion mode or the exhaust mode when one of the heat storage combustion burners is in the purge mode. A method for operating a regenerative combustion type gas processing apparatus, characterized in that time is controlled. 7. The method according to claim 6, wherein the processing gas is an odorous gas containing a malodorous component or a harmful gas containing dioxin.