JPH0959644A - Air blowing method for coke dry fire extinguishing equipment - Google Patents

Abstract

(57) An object of the present invention is to provide an air blowing method which minimizes a decrease in steam generation amount even when the concentration of combustible components in circulating gas or the amount of heat carried into red hot coke fluctuates. SOLUTION: In order to increase the steam generation amount of a waste heat boiler 7, in a method of blowing air into a circulating gas, a blower port 1 is provided in a downstream chamber of a dust removing plate 6 along a flow direction of the circulating gas.
An air blowing method in a coke dry fire extinguishing facility in which a plurality of 3a, 13b, and 13c are provided, and one blowing port is selected and blown according to the concentration of combustible components in circulating gas or the amount of heat input of red hot coke. [Effect] The maximum amount of steam can be recovered based on the concentration of combustible components in the circulating gas or the amount of heat input.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air blowing method for maximizing the amount of waste heat boiler steam generated in coke dry fire extinguishing equipment.

[0002]

2. Description of the Related Art For the purpose of energy saving and environmental protection, red hot coke is introduced into a cooling tower, and cooling gas is blown from the lower part of the cooling tower to cool it, and the gas is introduced into a waste heat boiler to generate steam for heat recovery. So-called coke dry fire extinguishing equipment (hereinafter referred to as CDQ) is used.
However, the steam generation amount of this CDQ is directly influenced by the charging amount of the red hot coke to be cooled and the temperature of the charging coke. For example, if the amount and temperature of the red hot coke discharged from the coke oven and charged into the cooling tower temporarily increase or decrease due to kiln removal, the temperature of the exhaust heat gas will change, and the waste heat boiler will change. The amount of steam generated will increase or decrease. As a result, it is difficult to quantitatively control the steam generation amount or control the maximum steam load of the turbine.

The applicant has already filed a patent application for an air blowing method for increasing the amount of steam generated in a waste heat boiler.
No. 238817 (filing date: October 3, H.6). This method will be described below. In FIG. 4, the low temperature circulating gas sucked by the circulating fan 1 is blown from the lower part of the cooling chamber 2. This low-temperature circulating gas exchanges heat with the red hot coke 3 charged in the cooling chamber 2 to become a high-temperature circulating gas, and enters the duct 5 via the flue 4. A dust removing plate 6 is provided in the duct 5, and the dust removing plate 6 removes fine coke from the circulating gas. The circulating gas from which the fine coke has been removed generates steam in the waste heat boiler 7, and is itself cooled to become a low temperature circulating gas. The low-temperature circulating gas that has exited from the waste heat boiler 7 is dedusted by the dust collector 8 and is again sucked into the circulating fan 1. The hot circulating gas entering the duct 5 through the flue is a combustible component (CO, H ₂
Etc.) are included. The amount of this combustible component varies depending on the temperature and properties of the red hot coke.

In such a coke dry fire extinguishing facility, in order to carry out the above method, an air blow pipe 11 is provided at the flue outlet, an air blow pipe 12 is provided upstream of the dust removing plate 6, and a dust removing plate 6 is provided.
An air blowing pipe 13 is provided downstream of the
Near the entrance to the waste heat boiler and thermometer 2 near the entrance
3 are provided. A flame detector 24 is provided near the waste heat boiler inlet. Then, air is blown into the flue outlet and the upstream and downstream of the dust removal plate to burn combustible components in the circulating gas, so that the air blown from the air blowing position to the boiler as compared to the case of blowing only at the flue outlet. Since the distance can be shortened, the amount of heat dissipated from the duct wall is reduced, and the amount of steam generated in the waste heat boiler 7 can be increased.

Further, when a flame is detected by the flame detector 24, the blowing amount of the air blowing pipe 13 downstream of the dust removing plate is reduced to prevent the flame from hitting the evaporation pipe of the waste heat boiler,
It is intended to extend its life.

[0006]

However, even in the case of the air blowing method as described above, if there is only one blowing pipe in the downstream chamber of the dust removing plate, the amount of combustible components in the circulating gas and carry-in In some cases, it is difficult to cope with the change in flame length in the downstream chamber of the dust removing plate due to the change in heat quantity.

That is, for example, when the amount of combustible components in the circulating gas and the amount of heat carried in are increased, the flame length becomes too long, so the amount of air blown in must be reduced to shorten the flame length. Therefore, there is a problem that the temperature of the circulating gas is lowered and the amount of steam generated in the waste heat boiler is reduced. On the contrary, when the amount of combustible components and the amount of heat carried in the circulating gas decrease, the flame length becomes too short and the efficiency of heat transfer to the boiler decreases.

According to the present invention, even when the amount of combustible components in the circulating gas or the amount of heat carried into the red hot coke fluctuates, the air blowing position downstream of the dust removing plate is optimally adjusted to minimize the decrease in the amount of steam generated. The purpose is to provide.

[0009]

SUMMARY OF THE INVENTION The present invention provides the above object,
Multiple air outlets are provided in the downstream chamber of the dust removal plate along the flow direction of the circulating gas, and one air inlet is selected according to the amount of combustible components in the circulating gas or the amount of heat input of the red hot coke. Achieve by blowing.

As a result, the flame length can be adjusted, the heat exchange efficiency in the waste heat boiler is improved, and the decrease in the steam generation amount can be minimized.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating an embodiment of the present invention. In FIG. 1, the same parts as those in FIG. 4 are designated by the same reference numerals and the description thereof will be omitted. In order to carry out the present invention, in the downstream chamber of the dust removing plate 6 along the flow of the circulating gas, at three locations from the upstream side, the upstream blowing pipes 13a,
The middle-flow blowing pipe 13b and the downstream blowing pipe 13c are provided at regular intervals.

Reference numeral 14 is an air blowing blower for supplying air to the blowing pipe. The air sucked by the air suction blower 14 passes through the pipe 15, the flow meter 16, and the flow rate adjusting valve 17 to the blow pipe 11, and the pipe 15, the flow meter 18, and the flow rate adjusting valve 1
9 to the blow pipe 12, and the pipe 15 and the flow meter 2
0a, flow rate adjusting valve 21a, or pipe 15, flow meter 20
b, flow rate adjusting valve 21b, or pipe 15, flow meter 20
c, the blow pipe 13a, the blow pipe 13b, or the blow pipe 1 through one path selected from the flow rate adjusting valve 21c.
It is distributed and supplied to one of 3c.

Reference numeral 25 is a gas component detector for sucking the circulating gas downstream of the circulating fan 1 and analyzing the component.

Reference numeral 30 denotes a means for distributing the air blowing amount obtained based on the circulating gas amount, the combustible component of the circulating gas and the empirical value to the air blowing pipes at respective positions at a constant ratio, and the gas component detector 25. The amount of the combustible component of the circulating gas flowing into the downstream chamber of the dust removal plate, which is obtained based on the concentration of the combustible components (H ₂ , CO, etc.) in the transmitted gas component, causes the downstream chamber blow pipe of the dust removal plate to be controlled. It is an arithmetic unit having means for selecting and determining.

The amount of air blown into the blow pipe at each position is such that the temperature of the circulating gas in the blow pipe 12 is 740 ° C. or higher, which is the temperature for burning H ₂ which is the main component of the circulating gas, and is discarded. Circulating gas temperature at the inlet of the heat boiler is 100
It is determined to be 0 ° C. or lower (allowable temperature for protecting the superheated pipe of the waste heat boiler).

The method of the present invention is performed by the above-mentioned equipment as follows. From the air blowing amount distribution means of the computer 30, the opening corresponding to the air blowing amount at each position is determined by the flow rate adjusting valve 1.
7, 19 and the flow rate adjusting valve (21a,
21b, 21c), and blow pipes 11, 12 are instructed.
And the blow pipes (13a, 13b, 13) in the downstream chamber of the dust removing plate.
One air injection amount in c) is controlled to the commanded distribution flow rate.

In the downstream chamber blow-in pipe selecting means of the computing unit 30, the computation and judgment of the contents shown in FIG. 2 are performed,
The selection of the blow pipe is performed. First, the amount of combustible components is obtained from the amount of circulating gas flowing into the downstream chamber of the dust removing plate and the gas component of the circulating gas.

The amount of combustible components is obtained, for example, as the sum of the concentrations of CO and H ₂ which are combustible components in the circulating gas. Table 1 shows an example of the components of the circulating gas and the amounts of combustible components.

[0019]

[Table 1]

Next, a blow pipe is selected according to the amount of combustible components. The amount of combustible components, which is the standard for selecting the blow pipe, can be empirically determined. For example, the amount of combustible components is 78 g / N
When m ³ or more, the blow-in pipe 13a has a combustible component amount of 78 g /
When less than Nm ^{3 and} 46 g / Nm ³ or more, the blow pipe 13b is
When it is less than 46 g / Nm ^3, the blow pipe 13c is selected.
When the flame is detected by the flame detector 24 due to an increase in the amount of combustible components or the like while blowing through the blow pipe 13c, the blow pipe 13b is switched to. In addition, when the flame is detected by the flame detector 24 due to an increase in the amount of combustible components while blowing through the blow pipe 13b, the blow pipe 13a is switched to. At this time, when the flame is detected by the flame detector 24, the air blowing amount is reduced. The above control can always be performed to maximize the amount of steam recovered in the waste heat boiler.

Since the amount of combustible components is proportional to the amount of heat input (coke temperature x cut amount) carried by the red hot coke charged into the cooling tower, the selection of the blowing pipe in the downstream chamber of the dust removing plate is carried by the red hot coke. It can also be performed based on the amount of heat input.

FIG. 3 is a graph showing the relationship between the heat input amount (coke temperature × cutout amount) and the vapor recovery amount depending on the position of the blowing pipe in the downstream chamber of the dust removing plate. FIG. 3 shows that selecting a blow pipe can maximize the amount of vapor recovery depending on the range of heat input. That is, the relationship between the range of heat input and the blow pipe that maximizes the amount of steam recovery is as follows. Low heat input (19 × 10 ⁴ kg. ° C / H or less)
When; the blow-in pipe 13c at the downstream position has an average heat input amount (19 × 10 ^{4 to} 19.8 × 1)
0 ⁴ kg. When the heat input is large (19.8 × 10 ⁴ kg. ° C./H or more), the blow pipe 13a at the upstream position is the same as the blow pipe selection control method described above. The control method is the same as the control method based on the amount of combustible components in the circulating gas.

In the above-mentioned embodiment, the example in which the air blow-in pipes of the dust removing plate downstream chamber are provided at three locations, the number of blower pipes provided is two, four, etc. You just have to choose the right one.

[0024]

According to the present invention, since the air blowing pipes are provided at a plurality of positions in the downstream chamber of the dust removing plate, the maximum amount of vapor can be recovered based on the amount of combustible components or the amount of heat input in the circulating gas. it can.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating an embodiment of a method of the present invention.

FIG. 2 is an example of a position selection flowchart of an air blowing pipe.

FIG. 3 is a graph showing the relationship between the amount of heat input and the amount of vapor recovery depending on the position of the blow pipe in the downstream chamber of the dust removing plate.

FIG. 4 is a block diagram illustrating a conventional method.

[Explanation of symbols]

 1 Circulation Fan 2 Cooling Chamber 3 Red Coke 4 Flue 5 Duct 6 Dust Removal Plate 7 Waste Heat Boiler 11 Air Blow Pipe (Flew Outlet) 12 Air Blow Pipe (Dust Remover Upstream Chamber) 13a Upstream Blow Pipe 13b Middle Flow Blow Pipe 13c Downstream Blow Pipe 16, 18, 20a, 20b, 20c Flowmeter 17, 19, 21a, 21b, 21c Flow rate adjusting valve 22, 23 Thermometer 24 Flame detector 25 Gas component detector 30 Computing unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenichi Nemoto 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Pipe Co., Ltd.

Claims (1)

[Claims] 1. A method for blowing air into a circulating gas to a waste heat boiler in a coke dry fire extinguishing facility, wherein a plurality of blowing ports are provided in a downstream chamber of a dust removing plate along the flow direction of the circulating gas. An air blowing method in a coke dry-type fire extinguisher facility, characterized in that one of the blowing ports is selected to blow air according to the amount of combustible components in the gas or the amount of heat input carried by the red hot coke. .