JPH10185177A - Regenerative burner type heating furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a regenerative burner type heating furnace which enables accurate control of discharging a combustion exhaust gas without increasing burden on an equipment surface. SOLUTION: Regenerative burners A and B are installed facing each other and the roles on the combustion side and the exhaust side are switched at a specified timing to discharge all exhaust gases to an exhaust path 30 from the regenerative burner B. Also provided are an exhaust gas flow regulating valve 34 provided in the exhaust path 30, an exhaust flow rate controller 50 to control the valve travel of the exhaust gas flow adjusting valve 34, an arithmetic device 40 for calculating a specified flow rate of an exhaust, a furnace pressure controller 47 for correction to compensate for a furnace pressure and an exhaust gas temperature controller 45 for correction to compensate for the temperature of an exhaust gas. Thus, a correction value of the furnace pressure and a correction value of the temperature can be allowed for the set value of the flow rate of the exhaust thereby eliminating a flue direct connected to a heating furnace 2 and the control of the furnace pressure and the control of the temperature of the exhaust gas are accurately accomplished simply by opening or reducing the flow regulating valve 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heating furnace provided with a regenerative burner combustion system.

[0002]

2. Description of the Related Art Conventionally, a heating furnace equipped with a regenerative burner combustion system has a regenerative burner device arranged facing the side of the heating furnace, and is provided separately from the exhaust path from the regenerative burner device. An exhaust gas flue is provided directly connected.

In such a regenerative burner combustion system, for example, the operation of supplying fuel and combustion air to one regenerative burner device of a furnace to perform combustion and sucking combustion exhaust gas from the opposite regenerative burner device is performed by a combustion operation. The operation is performed with the roles of suction and suction alternated. As a result, the heat of the combustion exhaust gas is stored in the regenerator of the regenerative burner device on the suction side, and is used for heating the combustion air blown into the furnace when the combustion side is next set.

JP-A-8-4670 discloses that a part of combustion exhaust gas is exhausted from an exhaust gas flue provided directly connected to the heating furnace itself. However, the flue gas flue as shown in the above publication is provided with a large diameter. Therefore, the site is restricted, a heat exchanger is provided in the middle of the flue to reduce the temperature of the flue gas, and a damper for controlling the furnace pressure is provided in order to exhaust the high temperature flue gas. On the other hand, a flow rate control valve is provided in the exhaust path of the regenerative burner device, and an exhaust amount control valve is further provided behind the flow control valve via a blower.

As described above, if a large-diameter flue is provided, a large site for the flue must be provided, or a damper and a heat exchanger must be additionally provided. Therefore, the burden on facilities was heavy. Further, there is a problem that sufficient exhaust control cannot be achieved by providing a blower in the middle of the exhaust path of the regenerative burner device and adjusting the amount of exhaust of the combustion gas behind the blower.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a regenerative burner type heating furnace capable of surely controlling the emission of combustion exhaust gas without increasing the load on facilities.

[0007]

Means for Solving the Problems, Embodiments of the Invention and Effects of the Invention Claims have been made to achieve the above object.
According to the described invention, a plurality of regenerative burners having a heat storage device are installed in a furnace body, the plurality of regenerative burners are divided into a combustion side and an exhaust side, and the roles of the combustion side and the exhaust side of the regenerative burner are switched at a predetermined switching timing. In the regenerative burner heating furnace which is switched every time, all the combustion exhaust gas in the furnace is discharged outside the furnace through a regenerative burner on the exhaust side.

According to the first aspect of the present invention, all of the combustion exhaust gas discharged from the combustion side burner is exhausted through the exhaust side burner, so that a flue and ancillary equipment directly connected to the heating furnace become unnecessary. Therefore, the burden on facilities is small and the vacant site can be used effectively. In addition, the exhaust gas of high temperature is exhausted after the heat is exchanged through a regenerator provided in the burner on the exhaust side, and the exhaust gas is exhausted after low temperature. Therefore, only the conventional regenerative burner device is sufficient. Further, since all the combustion exhaust gas is passed through the regenerator on the exhaust side, the heat recovery efficiency is improved, and the combustion air can be sufficiently heated at the time of the next combustion.

More specifically, as described in claim 2, a plurality of regenerative burners having regenerators are installed in a furnace body, and the plurality of regenerative burners are divided into a combustion side and an exhaust side. An exhaust gas flow control valve for switching the roles of the combustion side and the exhaust side of the exhaust gas at predetermined switching timings, and for adjusting the flow rate of the combustion exhaust gas discharged from each of the regenerative burners to the exhaust path; and Exhaust gas flow control means for controlling the opening degree of the exhaust gas from the exhaust side regenerative burner to the outside of the furnace at a desired flow rate, the exhaust gas flow control means, A flue gas amount instructing means for instructing an amount of flue gas, and a regenerative burner on the exhaust side based on an instruction result of the flue gas amount instructing means. Exhaust gas flow rate calculating means for calculating an exhaust gas flow rate required to discharge the exhaust gas, and a total amount discharge controlling means for controlling an opening degree of the exhaust gas flow rate adjusting valve based on an exhaust gas flow rate calculation result by the exhaust gas flow rate calculating means. It is characterized by the following.

According to the second aspect of the present invention, the exhaust gas flow rate calculating means discharges all of the combustion exhaust gas from the regenerative burner on the exhaust side based on the amount of flue gas indicated by the flue gas amount indicating means. The required exhaust gas flow rate is calculated, and based on the calculation result, the total emission control means controls the opening of the exhaust gas flow control valve. In this way, all of the combustion exhaust gas is discharged out of the furnace through the regenerating burner.

It is to be noted that the flue gas amount indicating means may be constituted as a means for detecting a fuel supply amount and a combustion air supply amount to the combustion side regenerative burner and calculating a flue gas amount as needed based on the detection results. Alternatively, the operating conditions of the furnace may be set in steps such as high, medium, and low, so that the amount of the combustion exhaust gas is uniquely determined and instructed in accordance with the setting.

According to a third aspect of the present invention, in the regenerative burner type heating furnace according to the second aspect, the exhaust gas flow rate control means detects a furnace pressure and a furnace pressure sensor. Furnace pressure correction value calculating means for calculating a correction value of the combustion exhaust gas flow rate so that the furnace pressure falls within a predetermined range, based on a calculation result of the furnace pressure correction value calculating means,
Preferably, a furnace pressure correcting means for correcting the calculation result of the exhaust gas flow rate calculating means is provided.

According to the third aspect of the invention, the furnace pressure correction value is calculated so as to increase the exhaust gas flow rate when the furnace pressure is high, and to decrease the exhaust gas flow rate when the furnace pressure is low. The furnace pressure correction value will be calculated. Then, since the final exhaust gas flow rate is controlled in a manner reflecting the correction value, all exhaust gas can be discharged from the exhaust-side regenerative burner while maintaining the furnace pressure within a desired range.

Further, as described in claim 4, claim 2
4. In the regenerative burner heating furnace according to any one of the above items 3, the exhaust gas flow control means includes an exhaust gas temperature sensor for detecting an exhaust gas temperature, and an exhaust gas temperature sensor for detecting an exhaust gas temperature detected by the exhaust gas temperature sensor to fall within a predetermined range. Exhaust gas temperature correction value calculating means for calculating a correction value of the combustion exhaust gas flow rate, and temperature correction means for correcting the calculation result of the exhaust gas flow rate calculating means based on the calculation result of the exhaust gas temperature correction value calculating means. It is good to

According to the present invention, when the exhaust gas temperature is high, the exhaust gas temperature correction value is calculated so as to decrease the exhaust gas flow rate. Conversely, when the exhaust gas temperature is low, the exhaust gas flow rate is increased. The exhaust gas temperature correction value will be calculated. Then, since the final exhaust gas flow rate is controlled in a form reflecting the correction value, all exhaust gas can be discharged from the exhaust-side regenerative burner while maintaining the exhaust gas temperature within a desired range.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The regenerating burner type heating furnace 1 of the embodiment has a configuration as shown in FIG. It comprises burners A and B provided on the side wall of the heating furnace 2, a fuel supply path 10, a combustion air supply path 20, and an exhaust gas exhaust path 30.

The heating furnace 2 is not provided with a flue directly connected to the heating furnace as in the conventional example. The heat storage bodies 3 and 4 are provided inside the burners A and B. Fuel supply route 1
0 indicates that fuel supplied from the fuel supply port 11 is supplied to the pipe 12
To the burners A and B via the 13 and 14 are switching solenoid valves.

The combustion air supply path 20 supplies combustion air supplied from a blower 21 to a burner A or a burner B via a pipe 22. 23 is an opening / closing damper, 2
Reference numerals 4 and 25 denote switching solenoid valves. Exhaust gas exhaust path 30
Sucks and discharges the combustion exhaust gas from the burner B or the burner A via the pipe 32 by the blower 31. Reference numeral 33 denotes an opening / closing damper, and reference numerals 34 and 35 denote exhaust gas flow control valves which also function as flow control valves and switching valves. Reference numeral 7 denotes a furnace pressure sensor provided in the heating furnace 2.

FIG. 1 shows a state in which the burner A is in a combustion state and the burner B is in an exhaust gas exhaust path. The solenoid valve 13 is opened and the solenoid valve 14 is closed to supply combustion gas to the burner A, and the solenoid valve 24 is opened and the solenoid valve 25 is closed to supply combustion air from the blower 21 to the burner A. On the other hand, on the exhaust side, the flow control valve 34 is opened and the flow control valve 35 is closed to discharge the combustion exhaust gas from the burner B to the blower 31.
Suction and discharge with.

At this time, the flow control valve 34 shuts off the combustion exhaust gas /
It not only opens, but also stops during opening and closing, and regulates the flow rate of the combustion exhaust gas, thereby fulfilling the role of furnace pressure control. When a predetermined time comes, the respective electromagnetic valves and flow control valves are switched to burn the burner B side and discharge the combustion exhaust gas from the burner A side. In this way, when the combustion exhaust gas is discharged, the heat of the high-temperature combustion exhaust gas is stored in the regenerators 3 and 4, and the combustion air used for the next combustion is heated. or,
The furnace pressure can also be controlled by adjusting the flow regulating valve.

In this embodiment, 100% of the exhaust gas from the burner on the combustion side is exhausted from the burner on the exhaust side. Therefore, unlike the conventional example, there is no need to provide an extra flue, and the heat recovery efficiency of the heat storage device is improved. Next, an opening and closing system of the flue gas flow control valve of the embodiment will be described with reference to FIG.

The set value of the exhaust gas amount of the combustion exhaust gas is obtained by detecting the amount of the combustion gas flowing now by the flow rate sensor 15 provided in the fuel supply pipe of the burner A, and using the result of the detection as a computing unit 40.
Is calculated by multiplying the amount of combustion gas input to the arithmetic unit 40 by the theoretical amount of exhaust gas, and further taking into account excess air to calculate a normal amount of combustion.

Subsequently, the normal set value is multiplied by an exhaust ratio of 100% to calculate a combustion gas exhaust amount. Next, the temperature of the combustion exhaust gas from the burner B is detected by an exhaust gas temperature sensor 44, and the detected result is used as an exhaust gas temperature controller (TIC) 45.
To send a signal. By inputting this signal, the exhaust gas temperature controller (TIC) 45 instructs the arithmetic unit 40 to decrease the exhaust gas flow rate when the combustion exhaust gas temperature is high, and increase the exhaust gas flow rate when the exhaust gas temperature is low to maintain a predetermined temperature. Perform compensation for temperature compensation.

On the other hand, the furnace pressure is detected by a furnace pressure sensor 7 in the heating furnace 2, and the detected result is indicated by a furnace pressure controller (P
IC) 47. The furnace pressure controller (PIC) gives an instruction to increase the exhaust flow rate when the furnace pressure is high and to reduce the exhaust flow rate when the furnace pressure is low by inputting this signal.
The input from 47 is input to the arithmetic unit 40 to make correction for furnace pressure compensation.

Thus, the exhaust gas flow rate is set. The set value of the combustion exhaust gas in which the temperature factor and the furnace pressure factor are compensated for to the normal set value in this way is calculated by the calculator 40, and the calculated flow set value is sent to the exhaust flow controller (FIC) 50. On the other hand, the flow rate of the combustion exhaust gas in the exhaust gas
And a signal of the detected value is output to an exhaust flow controller (FI).
C) Send to 50. The exhaust gas flow controller (FIC) 50 calculates the measured value of the exhaust gas flow rate by the flow sensor 49 and the arithmetic unit 4.
The exhaust gas flow control value is compared with the indicated value from 0. If the measured value is larger than the indicated value, the opening of the exhaust gas flow control valve 34 is reduced. Conversely, if the measured value is smaller than the indicated value, the exhaust gas flow control valve 34 is opened. By increasing the degree, feedback control of the exhaust gas flow rate is performed.

As a result, the entire amount of the combustion exhaust gas can be discharged from the regenerative burner on the exhaust side to the outside of the furnace while maintaining the furnace pressure and the exhaust gas temperature within appropriate ranges. According to the present embodiment, the exhaust gas flow control valve 34 on the exhaust side of the regenerative burner device.
The exhaust gas flow can be adjusted only by itself, eliminating the need for a flue gas flue as in the conventional example,
There is no need for additional parts in the middle of the flue. Because of such a compact heating furnace without a large flue, equipment costs can be reduced.

Although the embodiments of the present invention have been described above, various implementations can be made without departing from the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a main part of a regenerating burner type heating furnace according to an embodiment.

FIG. 2 is an explanatory diagram showing an opening / closing system of a flow control valve in an exhaust gas exhaust path according to the embodiment.

[Explanation of symbols]

1 ... regenerative burner type heating furnace, 3, 4 ... regenerator, 10 ...
Fuel supply path, 13, 14, 24, 25 ... solenoid valve, 20
... combustion air supply path, 30 ... exhaust gas exhaust path, 34, 3
5: Flow regulating valve, A, B: Burner.

Claims (4)

[Claims] A regenerative burner having a regenerator is installed in a furnace body, and the plurality of regenerative burners are divided into a combustion side and an exhaust side. A regenerative burner, wherein the combustion exhaust gas inside the furnace is discharged out of the furnace through a regenerative burner on the exhaust side. 2. A plurality of regenerative burners having a regenerator are installed in a furnace body, and the plurality of regenerative burners are divided into a combustion side and an exhaust side. An exhaust gas flow control valve that adjusts the flow rate of the combustion exhaust gas discharged from each of the regenerative burners to the exhaust path, and controls the opening degree of the exhaust gas flow control valve to perform combustion at a desired flow rate. In a regenerative burner type heating furnace comprising exhaust gas flow rate control means for controlling exhaust gas to be discharged from the exhaust side regenerative burner to the outside of the furnace, the exhaust gas flow rate control means comprises: a combustion exhaust gas amount indicating means for indicating an amount of combustion exhaust gas; Calculating an exhaust gas flow rate required to discharge all of the combustion exhaust gas from the regenerative burner on the exhaust side, based on an instruction result of the exhaust gas amount instruction means; And exhaust gas flow rate calculating means for, based on the exhaust gas flow rate calculation result of the exhaust gas flow rate calculating means, regenerative burners heating furnace, characterized in that it comprises a total amount discharge control means for controlling an opening degree of the exhaust gas flow rate control valve. 3. The regenerative burner type heating furnace according to claim 2, wherein the exhaust gas flow rate control means includes: a furnace pressure sensor for detecting a furnace pressure; and a furnace pressure detected by the furnace pressure sensor falling within a predetermined range. Furnace pressure correction value calculating means for calculating a correction value of the combustion exhaust gas flow rate for making the furnace pressure correction means for correcting the calculation result of the exhaust gas flow rate calculating means based on the calculation result of the furnace pressure correction value calculating means And a regenerating burner type heating furnace. 4. The regenerative burner type heating furnace according to claim 2, wherein the exhaust gas flow rate control means comprises: an exhaust gas temperature sensor for detecting an exhaust gas temperature; Exhaust gas temperature correction value calculating means for calculating a correction value of the combustion exhaust gas flow rate so as to fall within the range; and correcting the calculation result of the exhaust gas flow rate calculating means based on the calculation result of the exhaust gas temperature correction value calculating means. A regenerative burner type heating furnace comprising: