JPH0350594B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for removing minerals from coal. In recent years, due to a review of energy sources, coal-based liquefaction, gasification, and COM (COAL OIL
MIXTURE) and the construction of coal-fired boilers. Therefore, it is necessary to separate various mineral lumps, metal pieces, etc. that coexist with coal from coal. Conventionally, heavy liquid separation methods using solvents with different specific gravities and manual sorting methods have been adopted as means for removing such foreign substances. However, these methods have not been able to completely separate foreign substances from coal. Moreover, the foreign material is usually much harder than coal. For this reason, when coal containing foreign matter is supplied to a coal-fired boiler, the following problems occur.
If foreign matter is present in the coal during the crushing process before it is blown into the boiler furnace from the burner, the hardness of the foreign matter is high and will damage the crushing section. Work is required to repair this damaged area. In the worst case, the entire plant will have to be shut down for this work. Furthermore, if foreign matter gets mixed into the crusher along with the coal, some of the crushed foreign matter will enter the boiler furnace and pass through the water pipes together with the combustion exhaust gas, causing so-called assemblage erosion that wears out the water pipes. There was a problem that caused it. The present invention has been made in view of these points, and provides a device for removing foreign matter from coal that can efficiently remove foreign matter such as minerals and metal pieces that coexist with coal before supplying it to a crusher. This is what we provide. That is, the present invention includes a first belt that conveys coal containing foreign matter, and a second belt that is installed directly below the conveying end of the first belt so as to partially overlap the end of the first belt. , a hopper installed directly below the discharge end of the second belt and connected to the crusher, and a hopper with a sweeping surface using the rear end as a fulcrum near the overlapped end of the second belt and the first belt. a sweeping plate installed so as to be tiltable in a direction away from the conveying surface of the second belt; a discharge pipe installed so as to communicate the sweeping surface with the inside of the discharge port; and a conveying surface of the first belt. an X-ray visible light converter installed opposite to the X-ray source with the first belt in between; The present invention is an apparatus for removing foreign matter from coal, which includes a signal processor that receives the output of the signal processor, and a brushing plate driver that operates the brushing plate in response to the output of the signal processor. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of an embodiment of the present invention. In the figure, 1 is the first conveyor that conveys the coal 2 containing foreign substances such as minerals and metal pieces.
It's a belt. An X-ray source section 3 is provided above the first belt 1 and facing the conveying surface. The X-ray source section 3 supplies X-rays 5 through the first belt 1 to an X-ray visible light converter 4 provided below and facing the X-ray source section 3. I'm starting to do that. The X-ray visible light converter 4 includes an X-ray image intensifier 6 that receives transmitted X-rays 5, and an image pickup tube 7 connected to the X-ray image intensifier 6. Visible light converted from X-rays 5 by the X-ray visible light converter 4 is supplied to a signal processor 9 via a monitor 8 connected thereto. The signal processor 9 includes an amplifier 10 and an oscilloscope 11 that receives the output from the amplifier 10. The signal processor 9 is adapted to supply a predetermined output signal that detects the presence or absence of a foreign object to a brushing board driver 12, which will be described later. Further, a second belt 13 consisting of a conveyor is installed directly below the discharge end of the first belt 1 so as to partially overlap this end. Second
A discharge pipe 14 for discharging foreign matter is installed near the rear end of the belt 13. A second brushing surface 15a is provided between the discharge pipe 14 and the second belt 13.
The sweeping surface 15a is freely tilted in a direction away from the conveyance surface of the belt 13, and at a predetermined tilt angle, the sweeping surface 15a
A cleaning plate 15 is attached so as to send the upper foreign matter 2a into the discharge port of the discharge pipe 14. The cleaning plate 15 is operated by a signal from the cleaning plate driver 12, and operates in synchronization with the conveyance operation of the coal 2 by the first belt 1. Second belt 13
A hopper 16 is installed directly below the unloading end. The hopper 16 is adapted to supply the coal 2 supplied from the second belt 13 to the crusher 18 via the supply device 17. Foreign matter removal device 2 in coal configured in this way
According to No. 0, the foreign matter 2b present in the coal 2 is removed as follows. First, the coal 2 containing foreign substances 2b such as minerals and metal pieces is placed on the first belt 1 and conveyed toward the crusher 18. 1st belt 1
When the coal 2 moving on the coal 2 comes directly under the X-ray source section 3, it is irradiated with X-rays 5. Irradiated X-ray 5
is a foreign matter 2 such as α-SiO ₂ in the coal 2.
a, an absorption curve as shown in FIG. 2A is shown, and an image A as shown in FIG. 3 is projected on the monitor 8. Furthermore, the signal-processed waveform A′ is
As shown in FIG. 4, it is observed with an oscilloscope 11. Similarly, when the foreign substance 2a is FeCO ₃ , it shows an absorption curve as shown in FIG. 2B, an image as shown in FIG. 3 is projected on the monitor 8, and an image as shown in FIG. The waveform shown in middle B′ is shown. Further, when the foreign object 2a is FeS ₂ , it shows an absorption curve as shown in FIG. 2C, an image as shown in FIG. 4 in figure
The waveform indicated by C′ is shown. In addition, D in Figure 3 is
The tip of a commonly used screwdriver is shown to help determine the size of the foreign object 2a. here,
The presence or absence of absorption of X-rays 5 by such foreign matter 2a is detected by an X-ray image intensifier 6, and converted into visible light through an image pickup tube 7. Thereafter, the signal is amplified by the amplifier 10 and supplied to the brushing board driver 12 as a signal indicating the presence of the foreign object 2a. Thus, the coal 2 is transferred from the first belt 1 to the second belt 13. At this time, the coal 2 falls onto the blowing board 15 all at once. The cleaning plate 15 receives an output signal from the cleaning plate driver 12 and tilts toward the discharge pipe 14 just when the foreign matter 2b is deposited on the cleaning surface 15a. This operation removes the foreign matter 2a from the discharge pipe 14.
to be discharged. Thereafter, the brushing plate 15 becomes parallel to the conveying surface of the second belt 13, and further tilts toward the conveying surface of the second belt 13, as shown by the arrow in the figure, to remove purified particles that do not contain foreign matter 2a. The coal 2 is guided to the second belt 13. The second belt 13 is
This coal 2 is supplied to a hopper 16. The hopper 16 continues to move the coal 2 from which the foreign matter 2a has been removed.
is supplied to the crusher 18 via the feeder 17. As described above, according to the apparatus 20 for removing foreign matter in coal, the foreign matter 2a such as minerals having a hardness greater than that of the coal 2 can be easily removed, thereby preventing the crushing part of the crusher 18 from being damaged. As a result, the performance of the crusher 18 can be improved. In addition, foreign matter 2a such as minerals that cause so-called assemblage erosion can be greatly reduced, improving the durability of the water tube group in the furnace connected to the crusher 18, and further reducing deposits to improve boiler efficiency. It is possible to improve this. As explained above, according to the device for removing foreign matter in coal according to the present invention, foreign matter such as minerals and metal pieces that coexist with coal can be efficiently removed before supplying the coal to a pulverizer. As a result, it is possible to prevent damage to the crushing part of the crusher and improve its performance, as well as improve the durability of the water tubes in the furnace connected to the crusher and improve boiler efficiency. It is something.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of an embodiment of the present invention, FIGS. 2A to 2C are explanatory diagrams showing X-ray absorption curves of a foreign object, and FIG. 3 is an explanatory diagram showing the size of the foreign object. FIG. 4 is an explanatory diagram showing the waveform of the same foreign substance on an oscilloscope. 1... First belt, 2... Coal, 2a... Foreign matter, 3... X-ray source section, 4... X-ray visible light converter,
5...X-ray, 6...X-ray image intensifier, 7...imaging tube, 8...monitor, 9...signal processor, 10...amplifier, 11...oscilloscope, 12...brush plate drive container, 13...second belt, 14...discharge pipe, 15...brush plate, 15a...
...Brushing surface, 16...Hopper, 17...Supplier,
18...Crusher, 20 ...Device for removing foreign matter in coal.

Claims (1)

[Claims] 1. A first belt that conveys coal containing foreign matter;
A second belt is installed directly below the conveyance end of the first belt so as to partially overlap the end of the first belt, and a second belt is installed directly under the discharge end of the second belt, and A sweeping surface is installed near the overlapping end of the connected hopper and the second belt and the first belt so as to be tiltable in a direction away from the conveying surface of the second belt with the rear end as a fulcrum. a sweeping plate, a discharge pipe installed so that the cleaning surface communicates with the inside of the discharge port, an X-ray source section installed facing the conveying surface of the first belt, and the first belt.
an X-ray visible light converter installed opposite to the X-ray source with a belt in between; a signal processor connected to the X-ray visible light converter; What is claimed is: 1. A device for removing foreign matter from coal, comprising: a brushing plate driver provided to operate a brushing plate.