JPH066929U - Slag blockage prevention device by plasma torch - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a slag blockage prevention device that can easily increase the size of a cyclone-type partial coal combustion furnace or a coal gasification furnace and can instantly heat the vicinity of the slag downflow port. [Structure] A plasma torch 20 is provided below the slag flow-down opening 14 such that the tip faces the slag flow-down opening 14. The plasma torch 20 preferably has a water cooling structure.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is a slag in a furnace for burning solid fuel (hereinafter, simply referred to as coal) such as coal and oil coke in a reducing atmosphere, such as a cyclone type partial coal combustion furnace and a coal gasification furnace installed as a front furnace of a boiler. The present invention relates to a blocking device.

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, in industrial furnaces such as boiler furnaces, those in which a cyclone type partial coal combustion furnace is provided in the furnace body as a front furnace are known. An industrial furnace equipped with such a front furnace is widely used because of its excellent combustion effect. As a structure of the conventional cyclone type partial combustion coal furnace, for example, as shown in Japanese Utility Model Laid-Open No. 60-76717, pulverized coal and air are introduced into the cyclone partial coal combustion furnace. There is disclosed a structure in which pulverized coal is burned with high efficiency by supplying and effectively mixing these as a high-speed swirling flow and burning. In Japanese Utility Model Publication No. 3-24978, a water-cooled cylinder device, in which a cylinder shaft penetrates through a slag flow port and can move up and down to near the water surface in a slag tank, is provided above the slag flow port to prevent slag blockage The device is described. On the other hand, as a slag clogging prevention device for a coal gasifier, a slag burner (oil burner) is installed near the slag flow port to heat the slag and prevent clogging.

[0003]

[Problems to be solved by the device]

 When a cyclone-type coal partial combustion furnace is scaled up, the water-cooled cylinder device as disclosed in the above Japanese Utility Model Publication No. 3-24978 has a problem such as bending of the cylinder shaft and is not easily enlarged. In addition, when a slag burner (oil burner) is installed in a coal gasification furnace, the slag burner cannot instantly heat the slag, so there is a problem in that the slag clogging prevention measures are delayed. The present invention has been made to solve the above problems, and an object of the present invention is to provide a slag blockage prevention device that can easily be upsized and can instantly heat the vicinity of the slag downflow port. It is a thing.

[0004]

[Means and Actions for Solving the Problems]

 To achieve the above objectives, a plasma torch, which can be easily enlarged, is installed at the slag outlet of a cyclone partial coal combustion furnace or a coal gasification furnace, and the plasma torch is operated periodically to open the outlet. By heating the flowing slag, it is designed to increase the fluidity of the slag and prevent clogging of the downflow port. The temperature at which the coal ash melts and flows, that is, the melting point varies depending on the type of coal, but is generally 1,300 to 1,500 ° C. A plasma torch can be used to instantly heat up to the melt point.

As shown in FIGS. 1 to 4, the device for preventing slag blockage of the present invention burns coal in a reducing atmosphere to separate gas and slag, and separates the separated slag from the slag flow port 14 at the bottom of the furnace. In the furnace which is designed to be discharged from the furnace, the plasma torch 20 is provided below the slag flow-down port 14 so that the tip faces the slag flow-down port 14. As shown in FIG. 1, the above-mentioned furnace is a cyclone type partial coal combustion furnace 12 installed as a front furnace of a boiler, and it is preferable that the plasma torch 20 has a water cooling structure as shown in FIG. The furnace is a coal gasification furnace 38 as shown in FIG. 4, and the plasma torch 20 preferably has a water cooling structure as shown in FIG.

[0006]

【Example】

 Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. However, unless otherwise specified, the shapes and relative arrangements of the constituent devices described in this embodiment are not intended to limit the scope of the present invention to them, and are merely explanatory examples. Nothing more. Embodiment 1 FIG. 1 shows an embodiment of the slag blockage prevention device of the present invention. Reference numeral 10 is a boiler furnace, and 12 is a cyclone type coal partial combustion furnace. A slag downflow port 14 is provided in the lower portion of the furnace 12, and a slag chute 16 and a slag tank 18 are disposed below the downflow port 14.

As shown in FIG. 2, the plasma torch 20 penetrates through the slag chute 16 and is installed at a position where the plasma flow reaches the slag downflow port 14 and at a position where the slag does not contact, facing obliquely upward. Has been. A plurality of plasma torches 20 may be attached depending on the capacity of the cyclone type partial coal combustion furnace 12.

The plasma torch includes a non-transfer type (non-transfer arc type) and a transfer type (transfer arc type), but it is preferable to use the non-transfer type in which a plasma jet is generated. 3 and 4 show an example of the non-transfer type plasma torch 20. The plasma torch 20 includes a positive electrode 22, a negative electrode 24, an air supply pipe 28 for supplying air to be a plasma gas 26, a wire 30 and a power source 32 for connecting both electrodes, a water cooling pipe outer cylinder 34 for covering the outside, It is composed of a water cooling pipe inner cylinder 35 inside the outer cylinder 34, a cooling water supply pipe 36 for supplying cooling water between the outer cylinder 34 and the inner cylinder 35, and the like. In this way, the water cooling pipe is a double pipe, and the cooling water passes between the inner cylinder 35 and the electrode of the plasma torch as shown by the arrow, and drains between the outer cylinder 34 and the inner cylinder 35. Are discharged to the outside. As the cooling medium, it is preferable to use water having a high water removal rate as described above.

Embodiment 2 FIG. 5 shows another embodiment of the slag blockage prevention device of the present invention. This embodiment is applied to the coal gasification furnace 38, and the plasma torch 20 is installed below the slag flow-down port 14. 40 is a refractory material. Other configurations and operations are similar to those in the first embodiment.

[0010]

[Effect of device]

 Since the present invention is configured as described above, it has the following effects. (1) Since the plasma torch is installed below the slag flow port, the high temperature plasma gas that can be locally heated instantaneously heats the vicinity of the slag flow port to reliably open and close the slug flow port. Can be prevented. (2) Since there are no sliding parts, there is little wear and failure (the electrodes need to be replaced regularly).

[Brief description of drawings]

FIG. 1 is a structural explanatory view showing an embodiment of a slag blockage prevention apparatus using a plasma torch of the present invention.

FIG. 2 is an enlarged view around the slag flow-out port in FIG.

FIG. 3 is a cross-sectional explanatory view showing an example of a plasma torch.

4 is a cross-sectional view taken along the line AA in FIG.

FIG. 5 is an explanatory view showing another embodiment of the slag prevention device of the present invention.

[Explanation of symbols]

 10 Boiler furnace 12 Cyclone type partial coal combustion furnace 14 Slag downflow port 16 Slag chute 18 Slag tank 20 Plasma torch 26 Plasma gas 34 Water cooling pipe outer cylinder 35 Water cooling pipe inner cylinder 38 Coal gasification furnace

Claims (3)

[Scope of utility model registration request] 1. A furnace in which coal is burned in a reducing atmosphere to separate gas and slag, and the separated slag is discharged from a slag flow port (14) at a lower part of the furnace, wherein a slag flow port (14) is provided. Below the plasma torch (2
0) is provided so that its tip faces the slag flow-out port (14), and a device for preventing slag blockage by a plasma torch. 2. The plasma torch according to claim 1, wherein the furnace is a cyclone type partial coal combustion furnace (12) installed as a front furnace of a boiler, and the plasma torch (20) has a water cooling structure. Slag blockage prevention device. 3. The apparatus for preventing slag clogging by a plasma torch according to claim 1, wherein the furnace is a coal gasification furnace (38) and the plasma torch (20) has a water cooling structure.