JPS6222071B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for continuously measuring the temperature of a moving grate in a combustion furnace.

In recent years, with the depletion of petroleum resources, the use of solid fuels such as coal, coke, bark, and waste tires has continued to increase.

One of the effective methods of burning these is a moving grate type combustion device.When burning solid fuel on a grate, the grate temperature, which is the lifeblood of this method, must be maintained below a permissible value. It is important to burn it while To do this, it is necessary to accurately measure the surface temperature of the moving grate. Furthermore, as the combustion temperature increases, clinker that forms on each slag becomes an important factor that inhibits combustion, but by measuring the surface temperature of the grate, it is possible to grasp the state of clinker formation. It is also possible to indirectly prevent the formation of clinker by establishing a combustion control method for a combustion furnace.

Conventionally, the temperature of a moving grate has been indirectly estimated by extracting the signal from a thermocouple attached to the side frame of the combustion furnace adjacent to each grate. If this is explained using a drawing, the first
In Figures 1 and 2, the solid fuel supplied into the combustion furnace b by the combustion feeder a falls onto the moving bed grate c and is completely combusted by the combustion air e supplied from the wind box d. do. The combustion gas f is discharged from the upper part of the combustion furnace b, and the combustion ash is discharged from the ash outlet g. The grate surface temperature was detected by a thermocouple h attached to a side frame i of the combustion furnace wall, and was connected to a temperature measuring device k via a compensating conductor j to measure the temperature.

As shown in the figure, the thermocouple h is installed in the corner of the combustion furnace, so combustion air does not pass through it sufficiently, so even if coal is deposited here, violent combustion is unlikely to occur, and it is possible to accurately measure the grate surface temperature. It could not be said that the measurements were being made accurately. Another problem was that a large number of thermocouples had to be placed in the direction of movement in order to determine the temperature distribution in the direction of movement of the grate.

The present invention eliminates these drawbacks and uses one or more thermocouples to accurately measure the temperature distribution in the moving direction of the grate in the center of the combustion furnace where solid fuel such as coal and coke is burned. In addition, we propose a method for continuous measurement, with the aim of accurately understanding combustion conditions, establishing combustion control methods to prevent grate burnout, and helping to design new combustion furnaces.
The feature is that the thermocouple attached to the movable grate of the combustion furnace is brought into contact with a fixed conductor installed in the wind box of the combustion furnace, and the thermocouple is moved in response to the movement of the grate. The present invention provides a method for measuring temperature of a moving grate in which the temperature of the grate is continuously measured by extracting a signal from the grate.

The present invention brings the thermocouple attached to the grate of the combustion furnace into contact with the conductor attached to the wind box as described above,
Since the signal from the thermocouple embedded in the grate of the combustion furnace is directly extracted to the outside, the surface temperature of the grate in the longitudinal direction of the combustion furnace can be determined almost continuously and accurately as the grate moves. The present invention also proposes an apparatus that can be used directly to carry out the above invention.
A thermocouple attached to the transfer grate, a conductor connected to the thermocouple, an insulator board to which the conductor is fixed, a conductor with one end fixed to the insulator board and a brush shape at the other end, and a conductor wire connected to the thermocouple with the same brush shape. A moving grate temperature measuring device comprising a fixed conductor that is in contact with the conductor and is attached to the wind box of the combustion furnace, a conductor that is connected to the fixed conductor and outputs a signal to the outside of the combustion furnace, and a temperature measuring device. It is characterized by:

In the present invention, as described above, the conductive wire that sends the signal of the thermocouple embedded in the grate is fixed at one end to an insulator board provided at the lower end of the grate, and the other end is shaped like a brush. It is possible to reliably maintain the contact between the box partition plates with the fixed conductors arranged and fixed on the top of the partition plates, and also to prevent incineration ash, etc. that falls from the gaps between the grate and onto the fixed conductor into the grate. There is no automatic sweeping action when moving, and the contact area with the fixed conductor can be kept clean, so it is possible to always obtain accurate grate surface temperature signals without noise. and,
As a result of being able to accurately grasp the formation status of clinker produced due to the high combustion temperature of the combustion furnace and other combustion conditions, it has become possible to establish combustion control methods to prevent grate burnout and to develop new grate materials. This can be used in the selection of combustion furnaces, as well as in the design of combustion furnaces.

The most preferred embodiment of the present invention will be described in detail below with reference to FIGS. 3 to 9.

In FIGS. 3 to 5, solid fuel such as coal or coke supplied into the combustion furnace 2 by the fuel supply device 1 falls onto the moving bed grate 3, and combustion air 5 is supplied from the wind box 4. Complete combustion occurs, and the combustion gas 6 is discharged from the upper part of the combustion furnace 2, and the combustion ash is discharged from the ash discharge port 7. Reference numeral 9 indicates a thermocouple embedded in the grate; 10 indicates a plurality of fixed conductors disposed above the wind box partition plates 8 so as to be in contact with the thermocouple 9; and 11 indicates the same fixed conductor. The body 10 is an insulator, 12 is a conducting wire made of the same material as the thermocouple 9, 13 is an insulated terminal connecting the conducting wire 12 and the compensating conducting wire 14, and 15 is a temperature measuring device.

As shown in the figure, the moving bed type combustion furnace 2 has several wind boxes 4 for properly distributing combustion air 5, and each wind box 4 is partitioned by a wind box partition plate 8. In order to reduce air leaks between the boxes 4, the gap between the grate 3 and the wind box partition plate 8 is made small, and further leakage countermeasures are taken (not shown), but the fixed conductor 10 and the conducting wire 12 are It can be attached to the lower part of the grid 3 and the upper end of the wind box partition plate 8. These details will be explained below. In Figures 6 to 9, 3 is a grate, 9
10 is a thermocouple, and 10 is a plate-shaped fixed conductor fixed to the upper end of the wind box partition plate 8 with a fixing fitting 23 and a bolt 24 together with an insulator 11. Reference numeral 16 denotes a conductive wire made of the same material as the thermocouple 9 and whose surface is covered with glass fiber, and one end of which is connected to the thermocouple 9 via an insulator terminal 17 . 18
It is made of the same material as the thermocouple 9 and has a brush 19 at one end.
The other end is connected to the conductor 1 via the insulator board 21.
This is a braided conducting wire connected to 6. Further, 20 is a braided conductor crimp clip, 22 is a rod whose upper end is fixed to the lower end of the grate 3 and is used to suspend the insulator board 21, 25 is an upper end fixed to the lower end of the grate 3,
The lower end is a spring fixed to the insulator board 21, and is used to press the brush 19 of the braided conducting wire 18 against the fixed conductor 11. Note that 26 indicates a groove for removing dust formed between the wind box partition plate 8 and the fixed conductor 10.

The signal from the thermocouple 9 embedded and attached to any grate 3 as described above is transmitted to the insulator terminal 17, the conductor 16, the insulator board 21, the braided conductor 18, and the fixed conductor 10, the same fixed conductor. 10
Conductor 12 connected to insulated terminal 1
3. The temperature is input to a temperature measuring device 15 via a compensating conductor 14, and the surface temperature of the grate 3 is indicated or recorded by this temperature measuring device. Since the fixed conductor 10 is installed at the same height as the upper end of the wind box partition plate 8, the fixed conductor 10
The brush 19 of the conductor 18 that comes into contact with the wind box partition plate 8
It can pass through the gap without any problem. Further, since the brush 19 of the lead wire 18 is pressed against the fixed conductor 10 by the spring 24, it also functions to remove combustion ash that falls onto the fixed conductor 10 from the grate gap. In the above example, the thermocouple was attached to the grate at only one place, but in reality it can be attached at two places in the direction of movement of the grate (one on the upper grate and one on the lower grate). preferable. Furthermore, by attaching the grate at several locations in the width direction of the grate 3, the grate temperature distribution in the width direction can also be known.

Note that in recent years, heat recovery air is often used as combustion air as an energy-saving measure, but in this embodiment, thermocouples and conductive wires made of the same material as the thermocouples are used in the high-temperature section of the combustion furnace 2. Since the connection with the compensation conductor 14 is made in the atmosphere outside the combustion furnace 2, the temperature indication value is accurate regardless of the temperature inside the wind box.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams showing a conventional grate temperature measuring method, in which FIG. 1 is a front view and FIG. 2 is a cross-sectional view taken from FIG. 1. 3 to 9 are explanatory diagrams showing one embodiment of the present invention, in which FIG. 3 is a front view, FIG. 4 is a cross-sectional view of FIG. 3, and FIG. 5 is a diagram showing a grate and fixed conductor. Enlarged view of main parts showing relationships, No. 6
The figure is a cross-sectional view of main parts showing details of how thermocouples and conducting wires are attached to the fire grate, Figures 7 and 8 are explanatory diagrams showing how fixed conductors are attached between wind box partition plates, FIG. 9 is an explanatory diagram showing how an insulator terminal for connecting a thermocouple and a conducting wire is attached to a grate. 2... Combustion furnace, 3... Moving bed grate, 4... Wind box, 9... Thermocouple, 10... Fixed conductor, 12...
...Conducting wire, 15...Temperature measuring device, 16...Conducting wire, 1
7...Insulator board, 18...Conducting wire, 19...Brush.

Claims (1)

[Claims] 1. A thermocouple attached to a movable grate of a combustion furnace is brought into contact with a fixed conductor disposed in a wind box of the combustion furnace, and the thermocouple is moved from the thermocouple in response to the movement of the grate. A method for measuring the temperature of a moving bed grate, characterized in that the temperature of the grate is continuously measured by extracting a signal from the grate. 2. A thermocouple attached to a moving grate, a conductor connected to the thermocouple, an insulator board to which the conductor is fixed, a conductor with one end solid to the insulator board and a brush-shaped end, and a conductor connected to the same brush. A fixed conductor that is in contact with a conductive wire of the shape of a combustion furnace and is attached to a wind box of a combustion furnace, and a conductor that is connected to the fixed conductor and outputs a signal to the outside of the combustion furnace, and a temperature measuring device. Floor grate temperature measuring device.