JP2587484B2 - Boiler dust meter - Google Patents

Description

The present invention relates to a boiler dust amount measuring device for measuring the amount of flying dust in a furnace such as a soda recovery boiler.

[Conventional technology]

In recent soda recovery boilers, the recovery rate of the chemical solution (Na content) has been improved, and the K and Cl components brought in from the wood have been accumulated and the K and Cl concentrations in the combustion ash tend to increase accordingly. At the same time, the steam conditions of the soda recovery boiler have been increased in temperature and pressure for the purpose of higher efficiency, and the problem of dust clogging of the high-temperature part heat transfer tubes in some soda recovery boilers has arisen. This is because the melting point of the combustion ash decreases with an increase in the K and Cl concentrations in the combustion ash, and the adhesion of dust adhering to the high-temperature part heat transfer tube increases. Further, increasing the temperature and pressure under the steam condition tends to increase the metal temperature of the high-temperature part heat transfer tube, and this problem is more likely to occur.

[Problems to be Solved by the Invention] K, in the combustion ash in the furnace of the soda recovery boiler as described above,
When implementing measures against dust clogging caused by an increase in Cl concentration, it is important to quantitatively grasp the amount of dust.

Conventionally, however, there is no apparatus for quantitatively measuring the amount of dust in the soda recovery boiler furnace, and human visual observation such as firefly observation with the naked eye has been performed.

[Means for solving the problem]

 The present invention has the following means in order to solve the above problems.

That is, as a boiler dust amount measuring device, an air cooling tube having a tip inserted into a predetermined position in a furnace, moving means for moving the air cooling tube in and out of the furnace, and a base end of the air cooling tube An air supply unit connected to the air supply tube to supply air, a temperature measurement unit at an insertion part in the furnace of the air cooling tube, and a control unit that receives a signal from the temperature measurement unit and controls an air supply amount of the air supply unit. .

[Action]

By the above means, an air-cooled tube is inserted at a predetermined position in the furnace of a boiler such as a soda recovery boiler, and the control unit controls the temperature so that the temperature becomes close to the metal temperature of the high-temperature part heat transfer tube.
In response to the signal from the temperature measurement means, the air supply amount of the air supply means is controlled. Therefore, the amount of dust adhering to the air cooling tube can simulate the actual amount adhering to the high temperature part heat transfer tube. Further, the air-cooled tube can be quantified by drawing out and lightening the air-cooled tube by a moving means after a predetermined time.
In this way, the amount of dust in the furnace can be measured.

〔Example〕

One embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, reference numeral 1 denotes a soda recovery boiler main body, which comprises a furnace 1a, a charbet 1b, a smelt discharge port 1c, a high temperature section heat transfer tube 1d, and a furnace wall 1e. Reference numeral 2 denotes a fuel (black liquor) supply line, and reference numeral 3 denotes a combustion air supply line. Reference numeral 10 denotes a main body of a boiler dust amount measuring device attached to a furnace wall 1e above the furnace 1a. In the soda recovery boiler configured as described above, the fuel and air supplied to the furnace 1a from the fuel (black liquor) supply line 2 and the combustion air supply line 3 are burned on the charbed 1b and inorganic components in the fuel are burned. Most of the smelt becomes molten smelt and smelt outlet 1c
From the furnace 1a. Then, a part of the dust becomes dust, flies up the furnace 1a along with the combustion exhaust gas, and adheres to the high temperature part heat transfer tube 1d and the like.

In order to measure the amount of adhesion, the main body 10 of the boiler dust amount measuring device is installed on the upper part of the furnace 1a. This apparatus is a device for quantitatively measuring the flying dust amount of the soda recovery boiler by attaching dust that flies upward in the furnace 1a along with the above-mentioned fuel exhaust gas, and collects and measures the dust. FIG. 2 is a diagram showing details of a boiler dust amount measuring device. In the figure, le is a furnace wall, and 1f is a viewing window installed on the furnace wall le. Reference numeral 10 denotes a main body of a boiler dust amount measuring device attached to the viewing window 1f, and includes a sealing lid 10a, an air cooling tube 10b, an air cooling middle grid 10c, a thermocouple 10d, a thermocouple lead wire 10e, and a moving cart 9b. , A base 9a, a flow rate controller 8, and a flow rate control valve 6. The viewing window 1f is a through hole provided in the furnace wall 1e facing the high temperature part heat transfer tube 1d. The air cooling tube 10b is vertically penetrated and attached to the sealing lid 10a that covers the through hole. The base of the air-cooling tube 10b is mounted on a horizontal carriage 9b with its axis horizontal. Further, a horizontal platform 9a on which the moving vehicle 9b is mounted is provided. At the insertion portion of the air cooling tube 1b in the furnace, a center lattice for passing air for cooling air around itself is provided coaxially. A thermocouple 10d is attached to the lower part inside the air cooling tube 10b at the tip, and the lead wire is connected to the air cooling tube 10b.
And is pulled out from the original part and connected to the flow rate controller 8. Further, the base end is connected to a factory air line 4 through an air supply line 5 through a flow control valve 6. The output of the flow controller 8 is input to the flow control valve 6.

In the above configuration, the air-cooled tube 1b is moved to and inserted into the predetermined position above the furnace 1a of the soda recovery boiler on the platform 9a. Air cooling tube 10b during operation of soda recovery boiler
The temperature signal is sent to the flow controller 8 from the thermocouple 10d. This temperature signal is converted into a flow signal by the flow controller 8, and by controlling the flow control valve 6, the amount of air sent to the air cooling tube 10b is controlled to maintain the temperature of the air cooling tube 10b at a predetermined temperature.

After a predetermined time, the carriage 9b is moved and the air-cooled tube 10b is
a drawn out. Thereafter, flying dust attached to the tube side of the air-cooled tube 10b is collected and lightened. Thereafter, it is inserted again into the draw furnace 1a, and by repeating the above-described operation, the flying dust amount of the soda recovery boiler can be measured. Therefore, monitoring can also be performed.

Next, an experimental example will be described with reference to FIGS. 3 and 4. FIG.
FIG. 3 is a diagram showing the insertion time into the furnace 1a and the amount of dust adhering when the combustion conditions are constant. It can be seen that there is a proportional relationship between the insertion time and the amount of dust adhering, and that the flying dust can be measured well. FIG. 4 shows the change over time in the amount of dust adhering when the load fluctuates. The change in the amount of flying dust due to fluctuations in boiler combustion conditions such as load fluctuation is well captured. It can be seen that the measured values well reflect the situation of the amount of flying dust in the furnace.

The set temperature of the thermocouple 10d in the above-mentioned experimental example was 500 ° C., and the air cooling tube was 50φ × 700 (inside the furnace) mm. When the temperature is 600 ° C. or higher, it is found that the adhered dust begins to melt and drop, errors are likely to occur, and the adhered dust may be difficult to peel off.

〔The invention's effect〕

As described above, an air-cooled tube with a controlled tube side temperature is inserted into a furnace of a boiler such as a soda recovery boiler, and dust adhering to the tube is collected and measured to measure the amount of dust flying in the furnace. According to the boiler dust amount measuring apparatus, the amount of flying dust in the furnace can be captured well, and the change in the amount of flying dust due to a difference in boiler operating conditions such as combustion conditions can be accurately measured.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention applied to a soda recovery boiler, FIG. 2 is a configuration diagram of a dust amount measuring device of the embodiment, and FIGS. 3 and 4 are diagrams of the embodiment. It is a measurement example explanatory view. 1… Soda recovery boiler body, 1a …… Furnace, 1b …… Chart, 1c …… Smelt discharge port, 1d …… High temperature part heat transfer tube, 1e …… Furnace wall, 1f …… Peephole, 2… Fuel (Black liquor) supply line, 3 ... combustion air supply line, 4 ... factory air supply line, 5 ... air supply line, 6 ... flow control valve, 8 ... flow controller, 9a ... 9b… Transportation trolley, 10… Main body of the dust amount measuring device, 10a …… Sealing lid, 10b …… Air cooling tube, 10c …… Air cooling middle grid, 10d …… Thermocouple.

Continuing on the front page (72) Inventor Pan Takatsuka 1-1-1, Akunoura-cho, Nagasaki-shi, Nagasaki Mitsubishi Heavy Industries, Ltd. Nagasaki Shipyard (72) Inventor Takayuki Maeda 1-1, Akunoura-cho, Nagasaki-shi, Nagasaki Mitsubishi Heavy Industries, Ltd. (56) References JP-A-55-111886 (JP, A) JP-A-60-148951 (JP, A) Jiko 30-15801 (JP, Y1)

Claims (1)

(57) [Claims] An air-cooling tube having a tip inserted into a predetermined position in a furnace, a moving means for moving the air-cooling tube in and out of the furnace, and air connected to a base end of the air-cooling tube. It is characterized by comprising: an air supply means for supplying, a temperature measurement means for an insertion portion of the air cooling tube in the furnace, and a control means for receiving a signal from the temperature measurement means and controlling an air supply amount of the air supply means. Boiler dust amount measuring device.