Refractory material protection and heat recovery device for melting furnace

Abstract

The utility model relates to a refractory material protection and heat recovery device for a melting furnace. The refractory material protection and heat recovery device comprises the melting furnace and a refractory material, the refractory material is arranged on the inner wall of the melting furnace; the two cooling devices are arranged in parallel and are positioned on the outer side of the refractory material; the cooling device is connected with at least one air supply device, and the air supply devices are used for inputting air into the cooling device. In addition, the device further comprises a secondary combustion chamber, and the melting furnace is connected with the secondary combustion chamber through a pipeline. By controlling the temperature of circulating air and arranging two paths of cooling devices in parallel, the refractory material is protected, and the heat recovery effect is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of hazardous waste disposal devices, in particular to a refractory material protection and heat recovery device for a melting furnace. Background Art

[0002] Because they contain toxic pollutants such as heavy metals and dioxins, solid wastes such as slag and fly ash produced by the incineration of hazardous waste, fly ash produced by the incineration of domestic garbage and municipal sludge, electroplating sludge and copper-containing sludge are hazardous wastes, which are very toxic. Vitrification technology is relatively efficient for such hazardous wastes, and can highly solidify environmentally harmful elements and have a significant volume reduction rate. Plasma melting technology is a type of vitrification technology, which requires the use of a melting furnace and refractory materials. Due to the complex main components of slag, the refractory materials of the melting furnace will be eroded, worn, corroded and other adverse effects on the refractory parts of the slag outlet flow channel due to long-term erosion and wear of high-temperature flowing slag, resulting in the refractory materials being very easy to damage. The refractory materials need to be replaced every once in a while, wasting a lot of costs. During the operation of the melting furnace, circulating cooling water is generally used to protect the refractory materials in the furnace body and slag outlet. Although this can protect the refractory materials, the cooling water also takes away a lot of heat. Since the outlet temperature of cooling water is generally only 50-60℃, it is very difficult to recycle it. The heat is generally cooled directly by cooling towers, which wastes a lot of energy. The cooling water can also easily reduce the fluidity of the slag, and in severe cases, the furnace may be dead and cannot run smoothly. In addition, the water cooling pipe is easily corroded by the corrosive components in the furnace, so that the circulating cooling water can easily flow into the slag outlet and contact with the slag, causing danger, and it is difficult to form a real protection for the refractory material.

[0003] Patent application number: 201721141726.2, application date: September 6, 2017, utility model name: A plasma melting system, the plasma melting system of the application includes a plasma melting device and a bottom ash drying device, the ash becomes molten in the plasma melting device, the outer shell of the plasma melting device has an air cooling structure and is cooled by air. The bottom ash is dried in the bottom ash drying device, and the dried bottom ash enters the plasma melting device. The bottom ash is dried by passing part of the hot air in the plasma melting device through the bottom ash drying device, and the hot air takes away the moisture in the bottom ash, thereby achieving the drying of the bottom ash. The furnace cooling and bottom ash drying method of the plasma hazardous waste ash melting system of the present application solves the problem of high furnace body surface temperature of the plasma hazardous waste ash melting furnace and reduced operating efficiency caused by excessively high bottom ash moisture content.

[0004] In the prior art, although air cooling is used to replace cooling water for furnace cooling, a large amount of energy is recovered, but there are two major problems: First, the cooling temperature is controlled at 50°C to 80°C. When the temperature of the outer shell of the melting furnace is reduced, the temperature of the refractory material on the inner wall of the melting furnace will also be reduced. The flue gas containing sulfuric acid, hydrochloric acid vapor and other corrosive substances in the furnace has a low dew point. When the cooling surface of the refractory material is lower than the dew point, the flue gas containing acidic components will condense into a liquid containing sulfuric acid on the heating surface of the refractory material, causing dew point corrosion to the refractory material and even the outer shell of the furnace body; second, the main purpose of air cooling in the prior art is to protect the outer shell of the melting furnace. After forced air cooling, the temperature of the outer shell is reduced to below 80°C. Although the comfort and safety of the operating environment of the personnel are guaranteed, there is a high risk of dew point corrosion. The main purpose of air cooling is also unrelated to refractory materials. Utility Model Content

[0005] In view of the defects of the prior art that the existing cooling protection technology will cause dew point corrosion to the refractory materials and the shell of the melting furnace and the energy cannot be recovered, the utility model provides a refractory material protection and heat recovery device for the melting furnace, which protects the refractory materials and achieves the effect of heat recovery by controlling the temperature of the circulating air and setting two cooling devices in parallel.

[0006] The technical solution provided by the utility model is:

[0007] A refractory material protection and heat recovery device for a melting furnace comprises a melting furnace and a refractory material; the refractory material is arranged on the inner wall of the melting furnace; and further comprises:

[0008] A cooling device, which is arranged in two parallel paths and is located outside the refractory material;

[0009] An air supply device, wherein the cooling device is connected to at least one air supply device; the air supply device is used to input gas into the cooling device.

[0010] Preferably, the cooling device is arranged between the outer wall of the melting furnace and the refractory material, and the outer wall of the melting furnace is provided with an air inlet hole and an air outlet hole.

[0011] Preferably, the cooling device is wound around the outer wall of the melting furnace.

[0012] Furthermore, it also includes a secondary combustion chamber; the melting furnace is connected to the secondary combustion chamber through a pipeline.

[0013] Preferably, at least one regulating valve is provided between the cooling device and the air supply device; the regulating valve is used to regulate the air flow rate entering the cooling device.

[0014] Preferably, at least one regulating system is provided between the regulating valve and the cooling device; the regulating system is used to detect the temperature of the air and control the opening of the regulating valve according to the detected temperature.

[0015] Preferably, the cooling device structure is a coil; and the air supply device is a blower.

[0016] Preferably, the secondary combustion chamber is provided with an annular air duct and an air distribution pipe; a plurality of through holes are evenly distributed on the furnace wall of the secondary combustion chamber, and the air distribution pipe is installed in the through holes; the air distribution pipe is communicated with the annular air duct.

[0017] Preferably, the pipeline for connecting the melting furnace and the secondary combustion chamber is also provided with an absorption expansion device; the absorption expansion device is used to absorb the thermal expansion of the cooling device after being heated.

[0018] Preferably, the height of the pipe opening of the air distribution pipe at the annular air duct is lower than the height of the pipe opening at the other side of the air distribution pipe.

[0019] Preferably, the air distribution pipe is connected to the outer wall of the secondary combustion chamber. The angle is 30° to 60°; the air distribution pipe does not extend out of the inner wall, and the distance a from the inner wall is 20mm to 50mm.

[0020] Preferably, the coil is a high-frequency resistance welded spiral fin tube, which can increase the heat exchange area by 4-5 times and reduce the consumption of cooling medium.

[0021] Compared with the prior art, the technical solution provided by the utility model has the following beneficial effects:

[0022] The utility model arranges two cooling devices, air supply devices, regulating valves and control systems in parallel, thereby preventing the entire device from failing and failing to cool the refractory material due to a failure of a device or equipment in one of the devices.

[0023] In addition, by detecting the temperature of hot air, the control system can reduce the risk of dew point corrosion of refractory materials and furnace shells caused by flue gas containing corrosive substances such as acidic gases in the furnace of the melting furnace due to low air temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the overall structure of a refractory material protection and heat recovery device for a melting furnace in one embodiment of the present application;

[0025] Figure 2 This is a front view of the annular air duct and air distribution pipe of the second combustion chamber in one embodiment of the present application;

[0026] Figure 3It is a top view of the annular air duct and air distribution pipe of the second combustion chamber in one embodiment of the present application;

[0027] Figure 4 It is a schematic diagram of the fin tube structure in one embodiment of the present application.

[0028] Explanation of the symbols in the schematic diagram:

[0029] Cooling device 1, air supply device 2, regulating valve 3, control system 4, annular air duct 5, air distribution pipe 6, absorption expansion device 7. DETAILED DESCRIPTION

[0030] In order to further understand the content of the utility model, the utility model is described in detail in conjunction with the drawings and embodiments.

[0031] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of implementation. The change or adjustment of their relative relationship should also be regarded as the scope of implementation of the present invention without substantially changing the technical content.

[0032] Example 1

[0033] like Figure 1 As shown, in this embodiment, the present application proposes a refractory material protection and heat recovery device for a melting furnace, which, in addition to a melting furnace and refractory materials, also includes two cooling devices 1 arranged in parallel. Cooling air is introduced into the cooling device 1 to reduce the temperature of the refractory material to prevent it from being eroded and worn by high-temperature flowing slag for a long time. The cooling device 1 is installed between the outer wall of the melting furnace and the refractory material, and an air inlet and an air outlet are provided on the outer wall of the melting furnace to connect the cooling device 1 to an external pipeline. The cooling device 1 generally adopts a coil, preferably, as Figure 4 As shown, the use of high-frequency resistance welded spiral fin tubes can increase the heat exchange area by 4-5 times and reduce the consumption of cooling medium.

[0034] like Figure 1 As shown, the air supply device 2 is used to supply cooling air into the cooling device 1. The air supply device 2 can generally be a blower or a compressor. Each cooling device 1 is equipped with at least one air supply device 2.

[0035] like Figure 1 As shown, the regulating valve 3 is used to adjust the air intake of the cooling air. When the regulating system 4 detects that the air temperature is higher than the set temperature (about 150°C), the regulating valve 3 increases the opening to increase the air intake; when the regulating system 4 detects that the air temperature is lower than the set temperature, the regulating valve 3 decreases the opening to reduce the air intake and reduce the risk of dew point corrosion. The regulating system 4 is preferably a thermocouple, and each cooling device 1 is equipped with at least one regulating valve 3 and one regulating system 4.

[0036] The reason for using two parallel cooling devices 1 is that when the air supply device 2 or the regulating valve 3 or the control system 4 or the cooling device 1 itself fails, it will not interfere with the overall operation of the other equipment, thereby reducing the risk and ensuring the service life of the refractory material.

[0037] In addition, the present application proposes a melting furnace refractory material protection and heat recovery device, such as Figure 1 As shown, it also includes a secondary combustion chamber for recovering hot air as combustion-supporting air. The secondary combustion chamber is connected to the melting furnace through a pipeline, and each pipeline is provided with at least one absorption expansion device 7 for absorbing the thermal expansion generated by the hot air to prevent the pipeline from being damaged due to excessive heat. Figure 2 , Figure 3 As shown, an annular air duct 5 is provided on the outer wall of the second combustion chamber, and an air distribution pipe 6 is provided inside the furnace wall. The annular air duct 5 is communicated with the air distribution pipe 6. The heated hot air first enters the annular air duct 5 and then enters the furnace of the second combustion chamber through the air distribution pipe 6.

[0038] More specifically, if Figure 2 , Figure 3 As shown, a number of through holes are evenly distributed on the furnace wall of the secondary combustion chamber, and an air distribution pipe 6 is installed in the through hole. The air distribution pipe 6 is tilted upward, that is, the height of the pipe opening located on the outer wall of the secondary combustion chamber is lower than the height of the pipe opening located on the outer wall of the secondary combustion chamber. This is for the purpose of allowing the hot air to be fully mixed with the flue gas after entering the secondary combustion chamber. The tilt angle of the air distribution pipe 6 is preferably 30° to 60°, and preferably, the tilt angle of the air distribution pipe 6 is 45°. In addition, in order to protect the air distribution pipe 6 and prevent it from being burned in the furnace of the secondary combustion chamber, the air distribution pipe 6 does not extend out of the inner wall of the secondary combustion chamber, and the distance is preferably 20mm to 50mm.

[0039] Example 2

[0040] In this embodiment, the present application proposes a refractory material protection and heat recovery device for a melting furnace, which includes, in addition to a melting furnace and refractory materials, two cooling devices 1 arranged in parallel. Cooling air is introduced into the cooling device 1 to reduce the temperature of the refractory material to prevent it from being corroded and worn by high-temperature flowing flue gas or slag for a long time. The cooling device 1 is wound around the outer wall of the melting furnace, and the cooling device 1 is connected to an external pipeline. The cooling device 1 generally adopts a coil, preferably, such as Figure 4 As shown, the use of high-frequency resistance welded spiral fin tubes can increase the heat exchange area by 4-5 times and reduce the consumption of cooling medium.

[0041] like Figure 1 As shown, the air supply device 2 is used to supply cooling air into the cooling device 1. The air supply device 2 can generally be a blower or a compressor. Each cooling device 1 is equipped with at least one air supply device 2.

[0042] like Figure 1 As shown, the regulating valve 3 is used to adjust the cooling air intake. When the regulating system 4 detects that the air temperature is higher than the set temperature (about 150°C), the regulating valve 3 increases the opening to increase the air intake; when the regulating system 4 detects that the air temperature is lower than the set temperature, the regulating valve 3 decreases the opening to reduce the air intake and reduce the risk of dew point corrosion. The regulating system 4 is preferably a thermocouple, and each cooling device 1 is equipped with at least one regulating valve 3 and one regulating system 4.

[0043] The reason for using two parallel cooling devices 1 is that when the air supply device 2 or the regulating valve 3 or the control system 4 or the cooling device 1 itself fails, it will not interfere with the overall operation of the other equipment, thereby reducing the risk and ensuring the service life of the refractory material.

[0044] In addition, the present application proposes a melting furnace refractory material protection and heat recovery device, such as Figure 1 As shown, it also includes a secondary combustion chamber for recovering hot air as combustion-supporting air. The secondary combustion chamber is connected to the melting furnace through a pipeline, and each pipeline is provided with at least one absorption expansion device 7 for absorbing the thermal expansion generated by the hot air to prevent the pipeline from being damaged due to excessive heat. Figure 2 , Figure 3 As shown, an annular air duct 5 is provided on the outer wall of the second combustion chamber, and an air distribution pipe 6 is provided inside the furnace wall. The annular air duct 5 is communicated with the air distribution pipe 6. The hot air first enters the annular air duct 5, that is, the annular air duct 5 is used to receive the hot air introduced into the pipeline, and then enters the furnace of the second combustion chamber through the air distribution pipe 6.

[0045] More specifically, a number of through holes are evenly distributed on the furnace wall of the secondary combustion chamber, and an air distribution pipe 6 is installed in the through hole. The air distribution pipe 6 is tilted upward, that is, the height of the pipe opening located on the outer wall of the secondary combustion chamber is lower than the height of the pipe opening located on the outer wall of the secondary combustion chamber. This is for the purpose of allowing the hot air to be fully mixed with the flue gas after entering the secondary combustion chamber. The tilt angle of the air distribution pipe 6 is preferably 30° to 60°, and preferably, the tilt angle of the air distribution pipe 6 is 45°. In addition, in order to protect the air distribution pipe 6 and prevent it from being burned in the furnace of the secondary combustion chamber, the air distribution pipe 6 does not extend out of the inner wall of the secondary combustion chamber, and the distance from the refractory material is preferably 20mm to 50mm.

[0046] Example 3

[0047] In this embodiment, the basic structure is the same as that of embodiment 1 or 2. More specifically, the air supply device 2 is frequency-controlled. Under normal working conditions, each air supply device 2 operates at 50% load. If one air supply device 2 fails, the other air supply device 2 is adjusted to 100% load, and all cooling air enters from one of the cooling devices 1.

[0048] The above schematically describes the present invention and its implementation methods, which are not restrictive. The drawings show only one implementation method of the present invention, and the actual structure is not limited thereto. Therefore, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A refractory material protection and heat recovery device for a melting furnace, comprising a melting furnace and a refractory material; the refractory material is arranged on the inner wall of the melting furnace; Features: Also includes, A cooling device (1), wherein the cooling device (1) is arranged in two parallel paths and is located outside the refractory material; An air supply device (2), the cooling device (1) is connected to at least one air supply device (2); the air supply device (2) is used to input gas into the cooling device.

2. A refractory material protection and heat recovery device for a melting furnace according to claim 1, characterized in that: The cooling device (1) is arranged between the outer wall of the melting furnace and the refractory material, and the outer wall of the melting furnace is provided with an air inlet hole and an air outlet hole.

3. A refractory material protection and heat recovery device for a melting furnace according to claim 1, characterized in that: The cooling device (1) is wound around the outer wall of the melting furnace.

4. The refractory material protection and heat recovery device for a melting furnace according to claim 1, characterized in that: It also comprises a secondary combustion chamber and a pipeline; the pipeline is used to pass the air heated in the cooling device (1) in the melting furnace into the secondary combustion chamber.

5. The refractory material protection and heat recovery device for a melting furnace according to claim 1, characterized in that: At least one regulating valve (3) is provided between the cooling device (1) and the air supply device (2); the regulating valve (3) is used to regulate the air flow rate entering the cooling device (1).

6. A melting furnace refractory material protection and heat recovery device according to claim 5, characterized in that: At least one regulating system (4) is provided between the regulating valve (3) and the cooling device (1); the regulating system (4) is used to detect the temperature of the heated air and control the opening of the regulating valve (3) according to the detected temperature.

7. The refractory material protection and heat recovery device for a melting furnace according to claim 4, characterized in that: The outer wall of the secondary combustion chamber is provided with an annular air duct (5) for receiving the hot air introduced by the pipeline; a plurality of through holes are evenly distributed on the furnace wall of the secondary combustion chamber, and air distribution pipes (6) are installed in the through holes; the air distribution pipe (6) is in communication with the annular air duct (5).

8. The refractory material protection and heat recovery device for a melting furnace according to claim 4, characterized in that: The pipeline used to connect the melting furnace and the secondary combustion chamber is also provided with an absorption expansion device (7); the absorption expansion device (7) is used to absorb the expansion of the hot air in the cooling device (1).

9. The refractory material protection and heat recovery device for a melting furnace according to claim 7, characterized in that: The height of the pipe opening of the air distribution pipe (6) at the annular air duct (5) is lower than the height of the pipe opening on the other side of the air distribution pipe (6).

10. The refractory material protection and heat recovery device for a melting furnace according to claim 7, characterized in that: The air distribution pipe (6) is connected to the outer wall of the secondary combustion chamber. The angle is 30° to 60°; the air distribution pipe (6) does not extend out of the inner wall, and the distance a from the inner wall is 20mm to 50mm.

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