JPS63188750A - Instrument for measuring superheater of recovery boiler - Google Patents

Abstract

PURPOSE:To permit measurement of the heat patterns of heaters so that the sticking condition of deposits is known and the use of water is minimized by using a two-dimensional image pickup device, etc., adjusted to the measurement wavelength suitable for measuring the heaters. CONSTITUTION:A black liquor 2 is ejected into a recovery boiler 1 and is burned to form the mound of the char bed 3. The combustion heat generated at this time heats the water in the heaters 4 in the upper part of the boiler 1 to form steam which rotates a turbine to generate electric power, etc. The radiation energy from the char bed 3, etc., is detected by the two-dimensional image pickup device 5 provided on the wall surface of the boiler 1. The output of the device 5 is computed by a computing means 6 and the stereoscopic shape, temp. pattern, etc., of the heaters 4 are displayed by a display means in nearly the real time. The heat patterns of the heaters 4 are thus measured in the above-mentioned manner, by which the sticking condition of the deposits is known and the use of the water is minimized.

Description

[Detailed Description of the Invention] [Industrial Application Field 1] This invention burns waste liquid (black liquor) after cooking wood chips to obtain pulp to obtain a char bed, and also obtains steam using a superheater. This is a measuring device for the superheater of a recovery boiler.

[Prior art] The black liquor prepared after separating the pulp contains NaOH, Na
2 Contains S, \a2co3, etc., and mixes Na2SO with a mixer.
4 is mixed, a reduction reaction is caused in a recovery boiler, and the mixture is combusted to form a char bed.

This combustion heat is used to turn the water in the superheater into steam, but various deposits tend to adhere to the outside of the superheater pipes, causing poor thermal efficiency.

Moreover, the inside of the boiler is filled with the various gas components mentioned above due to the combustion of black liquor, resulting in a poor atmosphere.Normally, the state of deposits cannot be visually detected, so if thermal efficiency decreases or overheating occurs periodically. Water was sprayed into the container to wash away the deposits.

[Problems to be solved by this invention] For this reason, the boiler temperature decreases each time, as the actual situation, such as where the deposits are attached, is not known and the boiler is rewashed, resulting in a significant drop in operation. This is a cause of poor efficiency. In addition, when water was added, it reacted with NaN sulfide, creating a high risk of explosion within the reactor.

In view of the above points, it is an object of the present invention to provide a measuring device for a recovery boiler superheater that can measure the heat pattern of the superheater, check the state of deposits, and minimize the use of water. I can do that.

[Means for Solving the Problems] This invention provides measurement wavelengths of 0.82 to 1.4 μm, 1.5 to 1.5 μm, and
Measure the heat pattern of the superheater using at least the 1.9 μm or 2.0 to 2.4 μm wavelength band or at least one wavelength in each wavelength band. It is a measuring device.

[Embodiment] FIGS. 1 and 2 are configuration explanatory diagrams showing an embodiment of the present invention.

In the figure, black liquor 2 is spouted and burned in a black liquor recovery boiler 1, and a mountain of char bed 3 is formed. The combustion heat generated at this time heats the water in the superheater 4 above the black liquor recovery boiler 1 and turns it into steam, which turns the turbine and obtains electric power. Then, the radiant energy from the superheater 4 and the like is detected by a two-dimensional imaging device 5 that uses a COD or the like provided on the wall of the recovery boiler 1 as an image carrier. The output of this two-dimensional imaging device 5 is calculated by a calculation means 6, and the three-dimensional shape, temperature (heat) pattern, etc. of the superheater 4 are displayed on a display means 7 such as a CRT in real time. In addition, if necessary, a light source 9 such as infrared light may be used.
Light is projected onto the superheater 4 to obtain a clearer image. Of course, if you can get natural sunlight, indoor lighting, etc., there is no need for a special light source.

As shown in FIG. 2, this two-dimensional imaging device 5 is housed in a protection tube 51 that is water-cooled as necessary through a transmission window 50 on the wall surface of the recovery boiler 1, and is installed in the front or inside (the image carrier A filter 8 whose wavelength is suitable for measuring the char bed 3 is provided in front of the char bed 3. The transmission wavelength of this filter 8 is determined as follows.

Inside the black liquor recovery boiler 1 where the char bed 3 is being burned, NaOH, Na2S, Na2C are present.
O3, Na2 SO4, H20, CO2, Na, etc. are included, and it is necessary to measure at wavelengths excluding spectrum lights of wavelengths related to these.

Na gas has a spectrum below 0.819 μm, and H
20 gas t, mainly 1.43.1.94.2.5~
There is absorption near 3.0 μm, and other elements and groups have absorption at around 3.0 μm.
There is a spectrum over m.

In order to eliminate these influences, the measurement wavelength of the two-dimensional archive image device 5 (transmission wavelength of the filter 8) is set to approximately 0°82 to 1.4°.
Wavelength bands such as μm, 1.5 to 1.9 μm, or 2.0 to 2.4 μm are effective. That is, at least one wavelength band from these wavelength bands or at least one arbitrary wavelength from these wavelength bands is selected and used. Alternatively, a combination of these may be used. By this, the shape, temperature (heat) pattern, etc. of the superheater 4 can be obtained.

In this way, the thermal pattern of the superheater 4 is obtained, but since the superheater 4 has a lower temperature between the superheater 4 and the intermediate part, for example, as shown in the signal diagram of FIG. The portion that is lower than the reference level temperature corresponds to the diameter Di of the pipe of the superheater 4, and when this diameter Di is a predetermined value [)0 or more, it is assumed that the deposit is large and an alarm is generated. In this case, the positional information i indicating where on the superheater 4 the deposit is attached is also output on the screen, and appropriate measures such as removing the deposit can be taken.

The details of the calculating means 6 are as shown in FIG. 4, for example, a diameter measuring means 61 measures the diameter Di from the width below the reference level temperature based on the image signal of the thermal pattern, and a diameter determining means 62 measures the diameter Di from the reference level temperature. [) When compared with 0, the position signal ei is output together with the alarm signal ea when the value is large.

Note that the calculation means 6 is constituted by a microcomputer or other calculation device. Furthermore, it is clear that the state of deposits can be sufficiently grasped by visually observing the thermal pattern on the display means 7.

"Effects of the Invention" As described above, the present invention uses a two-dimensional imaging device with a measurement wavelength suitable for measuring the superheater, so it is possible to obtain a sufficient thermal image of the superheater. Since the status of deposits can also be grasped, deposits can be removed efficiently, greatly improving operational efficiency.

[Brief explanation of the drawing]

1, 2, and 4 are configuration explanatory diagrams showing one embodiment of the present invention, and FIG. 3 is a signal explanatory diagram.

Claims (1)

[Claims] 1. In a recovery boiler that burns black liquor to form a char bed, the measurement wavelength for detecting radiant energy from a superheater installed on the wall of the recovery boiler is approximately 0.82 to
1.4 μm, 1.5-1.9 μm, or 2.0-2.
A two-dimensional imaging device that uses at least one wavelength band of a 4 μm wavelength band or at least one wavelength of each wavelength band, and a calculation means that calculates at least a thermal pattern from the output of the two-dimensional imaging device. A measurement device for a recovery boiler superheater, which is characterized by: 2. The measuring device for a superheater of a recovery boiler according to claim 1, further comprising a light source for projecting light onto the superheater. 3. The measuring device for a superheater of a recovery boiler according to claim 1 or 2, wherein the calculation means measures the state of adhesion of deposits on the superheater based on a heat pattern.