JPH01269057A - Continuous analyzer for unburned component - Google Patents

Abstract

PURPOSE:To time-serially and easily measure the unburned component in a duct by capturing the combustion ashes in the duct, burning the unburned component of the combustion ashes in a heating furnace and detecting generated CO2. CONSTITUTION:The combustion ashes 21 in the exhaust combustion gas in the duct 20 are separated by a cyclone 24 and accumulate in the lower part of the cyclone 24 when said exhaust gas is sucked by a suction fan 29. Solenoid valves 26, 27 are then opened and closed by the signal from a control device 54 and the combustion ashes 21 are supplied onto a sample tray 31 and are weighed by a weighing device 33. The device 33 and the tray 31 are then tilted by a tilting mechanism 32 to drop the sample 34 into a hopper 35. The solenoid valve 37 is opened by the signal from the device 54 to supply the sample in the hopper 35 to an electric furnace 9. The sample is heated at the time of passage in a ceramics pipe 38 and the unburned component in the sample is converted to CO2 which is introduced through a branch pipe 45 into an IR gas detector 46, by which the CO2 is detected. The unburned component is thus time-serially and continuously measured by converting the unburned component to the CO2 and determining the quantity of the unburned component from the IR absorption quantity of the CO2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a continuous analyzer that is applied to measuring the amount of unburned matter in combustion ash in coal-fired boilers and the like.

[Conventional technology]

In coal-fired boilers, it is important to measure the unburned content in the ash in order to understand the combustion state.

For this reason, currently, in accordance with Japanese Industrial Standards JIS M 8815, unburned content is determined from the weight loss no cent when heated to 815° C. using an electric furnace.

Further, in order to perform such analysis, a thermobalance as shown in FIG. 2 may be used. That is, a shutter 3 is installed on one side of the beam 2 of the balance placed on the support stand 1.
However, a sample container support tube 5 having a thermocouple 4 inside is attached to the other end. A photoelectric sensor 6 for detecting the deflection of the balance beam 2 is arranged next to the shutter 3. A sample container 7 is placed on the upper part of the sample container support tube 5, and a sample 8 obtained by sampling combustion ash is placed in the sample container 7. At the bottom of the sample container support tube 5 is an electromagnet 9, further below.

A weight adjustment mechanism 10 is attached, and a control coil 11 is placed next to the electromagnet 9. The photoelectric sensor 6 and the control coil 11 are connected to a weighing circuit 12, and the thermocouple 4 passed through the sample container support tube 5 is connected to a program temperature control unit 13 and a recording unit 14. Support stand 1
．． Balance beam 2° shutter 3. Photoelectric sensor 6, electromagnet 91, weight adjustment mechanism 10. The control coil 11 and the lower part of the sample container support tube 5 are housed in the container as a balance section 15. The upper parts of the sample container 7 and the sample container support tube 5 are covered with a protective tube 17 having a gas inlet/outlet 16. Furthermore, an infrared heating furnace 19 with a tungsten lamp 18 is arranged outside, which is connected to the program temperature control unit 13 .

The measurement principle of this thermobalance is as follows. The sample 8 is balanced on the beam 2, and when the weight of the sample 80 changes due to heating, the beam 2 tilts and is optically detected by the photoelectric sensor 6. Furthermore, the deflection output is amplified and the current of the control coil 11 is The beam 2 is then balanced again. K like this.

A change in the weight of the sample 80 is indicated by a change in the current of the control coil 11, and a recording unit 14 connected to the weighing circuit 12 records the sample temperature and sample weight change curve.

For this reason, when measuring the unburned content using a thermobalance, it is necessary to measure the unburned content based on the weight loss percentage when the combustion ash as sample 8 is placed in the sample container 7 and the heating furnace 19 is energized to heat the sample 8 to 815°C. I asked for a minute.

[Problem to be solved by the invention]

The conventional JIS method and the method using a thermobalance described above both sample the combustion ash in the duct and measure the amount of unburned matter. For this reason.

It took a long time to determine the amount of unburned matter, making it unsuitable for monitoring the amount of unburned matter in response to the combustion status of the boiler.

[Means to solve the problem]

The present invention takes the following measures to solve the above problems.

That is, a collection means for collecting combustion ash in the duct, a weighing device, a means for supplying the collected combustion ash onto the weighing device, a heating furnace, and a heating furnace for heating the combustion ash after weighing. A means for supplying into the furnace, and a detection means having an infrared gas detector for detecting carbon dioxide (CO□) generated by combustion of unburned components of the combustion ash in the heating furnace are provided.

[Effect]

According to the present invention, the combustion ash in the duct is collected and weighed, and then heated to a predetermined temperature and completely combusted, and the unburned content in the combustion ash is converted into carbon dioxide (COz) and -carbon oxide. (GO), and the amount of unburned gas is determined from the amount of infrared absorption of those gases.

In this way, a device that can easily measure the unburned content of combustion ash in the duct continuously in time series can be replaced.

〔Example〕

An embodiment of a continuous analyzer for unburned matter in ash according to the present invention is shown in FIG. Here, 20 is a duct, and combustion ash 21 is conveyed in the duct 20 in the direction of arrow a. One end 23a of the sample sampling tube 23 is arranged to face the flow of the combustion ash 21.

The other end 231) is connected to the cyclone 24.

A solenoid valve 26 and a solenoid valve 27 are sequentially arranged in a lower branch pipe 25 of the cyclone 24, and a gas return pipe 30 having a suction fan 29 that sucks gas in the direction of the arrow is connected to the upper part of the cyclone 24. has been done. Usually, the other end 30a of the gas return pipe 30 is connected to the duct 20.

A weighing device 33 is installed below the lower branch pipe 25 of the cyclone 24, and has a sample dish 31 fixed on its upper surface and an inclined fP+m structure 32 at its lower part. When the mechanism 33 is tilted, the sample plate 31
Place the hopper 35 in a position where the upper sample 34 is lowered.
is installed.

A solenoid valve 37 is installed in the middle of the lower discharge pipe 36 of the hopper 35.
is attached, and a porcelain pipe 38 is connected to the lower end 36a of the lower discharge pipe 36. The porcelain tube 38 is installed so that the center line of the tube is in the vertical direction, and the porcelain tube 38
A tubular electric furnace 39 is arranged so as to surround the. A branch pipe 41 having a solenoid valve 40 between the solenoid valve 37 attached to the lower discharge pipe 36 and the lower end 36a of the lower discharge pipe 36
is installed. A sample discharge pipe 43 having a solenoid valve 42 is connected to the lower end 38a of the porcelain tube 38, and a branch pipe 45 having a solenoid valve 44 is disposed above the solenoid valve 42 of the sample discharge pipe 43. . The branch pipe 45 is connected to an infrared gas detector 46 having an infrared absorption cell (not shown).

A thermocouple 47 is inserted inside the porcelain tube 38.

The thermocouple 47 is connected to a temperature control device [48], and the temperature control device 48 is connected to a heating element 49 disposed in the tubular electric furnace.
It is connected to the. Weighing device 33 and infrared gas detector 46 are connected to storage device 50 and storage device 51, respectively, and each storage device 50 and 51 is further connected to arithmetic unit +15.
2 to an output display device 53. Control device] 1t54 is a solenoid valve 26.27, 37.40.42,
44. It is connected to the tilting mechanism 32 and the arithmetic unit 52 to control them.

Quantification of unburned content using such a continuous analyzer for unburned content in ash is carried out in the following manner. First, the suction unit 29 is operated to suck the combustion exhaust gas in the duct 20. On this occasion,
Combustion ash 21 in the combustion exhaust gas is separated by the cyclone 24 and stored in the lower part of the cyclone 24. Next, a signal is sent from the control device 54 to open and close the electromagnetic valves 26 and 27, thereby supplying combustion ash onto the sample tray 31. The load thus applied on the weighing device 33 is stored in the storage device 50. After closing the solenoid valves 37 and 42 and opening the solenoid valves 40 and 44 by a signal from the control device 54,
From the branch pipe 41, a cylinder or the like is driven by a signal from the control device ff54 to drive the tilting mechanism 32 to tilt the weighing device 1t33 and the sample plate 31 fixed thereon, and lower the sample 34 into the hopper 35. . As the weighing device 33 in these configurations, an electronic top balance, a load cell, or the like is used, and the tilting mechanism has, for example, a fulcrum in a part thereof.

This can be achieved by, for example, disposing a circular cam in the other part and rotating the cam.

Next, the solenoid valve 37 is opened by a signal from the control device (t54), and the sample in the hopper 35 is fed into the tubular electric furnace 38. temperature (for example, 815°C) shall be controlled by K. When the sample passes through the porcelain tube 38, unburned matter in the sample is oxidized and becomes carbon dioxide (CO2).
The gas is guided through a branch pipe 45 to an infrared gas detector 46 . On this occasion.

Depending on the gas atmosphere inside the porcelain tube 38, carbon monoxide (CO
) may occur, but the amount of 1 generated is extremely small, and 1
Usually, sufficient accuracy can be obtained by only detecting carbon dioxide (COz). In order to obtain more accurate data (unburnt amount), it is desirable that K also determines the amount of carbon monoxide (CO) using a Mayuki infrared gas detector. The sample weight obtained by the weighing device 133 and the carbon dioxide (CO
2) After the concentrations are stored in the storage devices 50 and 51, the amount of unburned matter (%) is calculated by the calculation device tt52, and then displayed by the output display device [53]. Here, what is obtained by the infrared gas detector 46 is the volume percent of the normal gas (sample gas carrier gas), so the arithmetic unit j152 calculates the amount of carbon dioxide (CO□) generated from the sample by integrating it. It is necessary to calculate

Furthermore, solenoid valves 26.27.37°40.42,44. The tilt mechanism 32 and the calculation device 52 are controlled by the control device 54 based on the series of steps described above. By repeating the above operation, the unburned content in the ash can be measured in one time series.

In this way, a device that continuously measures the unburned content of combustion ash in the duct in a time-series manner can be easily replaced.

〔Effect of the invention〕

As explained above, 1. The in-ash ash continuous on/off analyzer of the present invention has a means for collecting combustion ash, a means for burning unburned matter, and a means for quantifying carbon dioxide (CO2) generated by combustion. It is an effective combination of means, and it is possible to continuously measure the unburned content in the duct in chronological order. Also, only one weighing device is required to weigh the initial sample amount.

The carbon dioxide generated by combustion is detected using an external gas detector, making it easy to install even in harsh locations with strong vibrations. Furthermore, since the infrared absorption method described above is used, compared to a weight detection method that calculates the amount of unburned matter from the sample weight before and after heating, it is possible to detect moisture (crystalline water, etc.) and SO2 gas (sulfate, etc.) present in the sample. (produced by the decomposition of) etc.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a continuous unburned content analyzer in ash according to the present invention, and FIG. 2 is a block diagram of a thermobalance conventionally used for measuring unburned content. a...Arrow indicating the flow direction of combustion ash. b...Arrow indicating the flow direction of suction gas. 20...Duct, 21...Combustion ash. 23... Sample collection tube, 24... Cyclone. 25... Branch pipe. 26.27, 37, 40, 42.44... Solenoid valve. 29... Suction fan, 30... Gas return pipe. 31... Sample dish, 32... Tilt mechanism. 33... Weighing device, 34... Sample. 35...Hopper, 36...Discharge pipe. 38... Porcelain tube, 39... Tubular electric furnace. 41... Branch pipe, 43... Sample discharge pipe. 45... Branch pipe, 46... Infrared gas detector. 47...Thermocouple, 48...Temperature control device. 49...Heating element, 50.51...Storage device. 52... Arithmetic device, 53... Output display device. 54...Control device. Agent: Patent attorney Akira Sakama (2nd group)

Claims (1)

[Claims] A collection means for collecting combustion ash in the duct, a weighing device, and a means for supplying the collected combustion ash onto the weighing device;
A heating furnace, a means for supplying the weighed combustion ash into the heating furnace, and an infrared gas detector for detecting carbon dioxide (CO_2) generated by combustion of unburned portions of the combustion ash in the heating furnace. 1. A continuous analyzer for unburned matter in ash, comprising: a detection means having the following.