High-temperature fluctuating dusty flue gas waste heat recovery device

Abstract

The utility model discloses a high-temperature fluctuating dusty flue gas waste heat recovery device. The high-temperature fluctuating dusty flue gas waste heat recovery device comprises a vertical U-shaped flue and a soot treatment mechanism located below the U-shaped flue. A high-temperature flue gas inlet is formed in the top of the left side of the U-shaped flue, a high-temperature flue gas outlet is formed in the top of the right side of the U-shaped flue, and a flow equalizing piece and a plurality of flue gas temperature stabilizing mechanisms used for stabilizing the temperature of high-temperature flue gas are sequentially arranged in the left side of the U-shaped flue from top to bottom. A heat exchange mechanism used for generating stable overheated or saturated steam is arranged in the right side of the U-shaped flue. The high-temperature fluctuation dusty flue gas waste heat recovery device can continuously generate stable overheated or saturated steam.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat recovery, in particular to a high-temperature fluctuating dust-containing flue gas waste heat recovery device. Background Art

[0002] With the proposal and promotion of the dual carbon goals, steel companies are facing severe pressure to reduce carbon emissions. Compared with converters, high-temperature electric furnaces can reduce CO2 emissions by 1.1 tons for every ton of steel produced, which has a good emission reduction advantage. The high-temperature electric furnace will produce furnace gas during the steel-making process. The furnace gas enters the mobile bend flue through the gap between the furnace cover bend and the mobile bend flue, and is mixed with a certain amount of air outside the furnace. After burning combustible gases such as CO in the furnace gas, high-temperature flue gas is formed, which contains a large amount of heat energy.

[0003] In order to improve the energy efficiency of high-temperature electric furnaces, it is necessary to recover the waste heat of the high-temperature flue gas of the electric furnace. However, the temperature of the flue gas generated by the high-temperature electric furnace during use is 200℃~1100℃ when it is discharged at the outlet of the settling chamber. The temperature fluctuates with the steelmaking process and varies greatly. For example, the flue gas temperature generated during the oxygen blowing period of the electric furnace is the highest, and the temperature of the flue gas at the outlet of the settling chamber is about 850℃. The temperature is the lowest during the molten iron tapping period, and the temperature of the flue gas at the outlet of the settling chamber is about 200℃. At present, the industry uses saturated steam waste heat boilers to recover the waste heat of high-temperature electric furnace flue gas, which can convert the heat energy of high-temperature flue gas into steam for power generation. However, due to the unstable temperature of electric furnace flue gas, the use of saturated steam waste heat boilers to recover the waste heat of high-temperature electric furnace flue gas can only produce unstable saturated steam, and cannot continuously produce stable superheated or saturated steam. Utility Model Content

[0004] Based on this, it is necessary to provide a high-temperature flue gas waste heat recovery device that can continuously generate stable superheated or saturated steam to address the above technical problems.

[0005] The utility model provides a high-temperature fluctuating dust-containing flue gas waste heat recovery device, comprising a vertical U-shaped flue and a smoke ash processing mechanism located below the U-shaped flue;

[0006] A high-temperature flue gas inlet is provided at the top of the left side of the U-shaped flue, and a high-temperature flue gas outlet is provided at the top of the right side of the U-shaped flue;

[0007] The left side of the U-shaped flue is provided with a flow equalizer and a plurality of flue gas temperature stabilizing mechanisms for stabilizing the temperature of the high-temperature flue gas from top to bottom;

[0008] A heat exchange mechanism for generating stable superheated or saturated steam is arranged inside the right side of the U-shaped flue.

[0009] In one embodiment, the flue gas temperature stabilizing mechanism is a plate-type, cylindrical or honeycomb structure;

[0010] The flue gas temperature stabilizing mechanism is entirely made of magnesia bricks, concrete or cast iron; or

[0011] The flue gas temperature stabilization mechanism includes a shell and a high-temperature phase change material filled inside the shell. The shell is made of 304 stainless steel or 347H stainless steel. The high-temperature phase change material is a chloride phase change material or a carbonate phase change material.

[0012] In one of the embodiments, the heat exchange medium of the heat exchange mechanism is water, and the heat exchange mechanism is provided with a superheater, an evaporator and an economizer from bottom to top.

[0013] In one of the embodiments, the heat exchange medium of the heat exchange mechanism is molten salt, and the heat exchange mechanism is provided with a flue gas molten salt heat exchanger and a steam generator from bottom to top.

[0014] In one embodiment, the ash handling mechanism includes a bracket, at least two ash hoppers and an ash conveyor arranged under each ash hopper. The bracket is fixedly connected under the U-shaped flue, the inlet of the ash hopper is connected to the lower side of the U-shaped flue, and the ash conveyor is connected to the outlet of the ash hopper.

[0015] In one of the embodiments, the high-temperature fluctuating dust-containing flue gas waste heat recovery device is also provided with a cleaning mechanism for cleaning the flue gas temperature stabilization mechanism and the heat exchange mechanism by using shock waves or vibration.

[0016] In one embodiment, the flow equalizing member is a guide plate or a flow equalizer.

[0017] Beneficial effects of the utility model:

[0018] (1) The utility model uses a high-temperature flue gas stabilization device to stabilize the high-temperature flue gas of 200°C to 1100°C to 500°C to 600°C, and then generates stable superheated or saturated steam through a heat exchange mechanism.

[0019] (2) The vertical U-shaped flue is conducive to the dust in the flue gas sinking to the bottom of the U-shaped flue, making it easier to clean the dust. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic structural diagram of a high-temperature fluctuating dust-containing flue gas waste heat recovery device provided in an embodiment of the utility model.

[0021] Explanation of the reference numerals: 1. high-temperature flue gas inlet; 2. flow equalizing member; 3. flue gas temperature stabilizing mechanism; 4. bracket; 5. ash hopper; 6. ash conveyor; 7. heat exchange mechanism; 8. high-temperature flue gas outlet. DETAILED DESCRIPTION

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below with reference to the accompanying drawings.

[0023] It should be noted that in the description of the present invention, “upper”, “lower”, “top”, “bottom”, orientation or position relationship is based on the attached Figure 1 Regarding the orientation or positional relationship shown, it should be understood that these orientation terms are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0024] In one embodiment, Figure 1 As shown, Figure 1 The high temperature fluctuating dusty flue gas waste heat recovery device provided by the embodiment of the utility model comprises a vertical U-shaped flue and an ash treatment mechanism located below the U-shaped flue.

[0025] The flue adopts a vertical U-shaped structure, which is conducive to the downward sedimentation of dust in the flue gas and convenient for centralized treatment of dust.

[0026] A high-temperature flue gas inlet 1 is arranged at the top of the left side of the U-shaped flue, and a high-temperature flue gas outlet 8 is arranged at the top of the right side of the U-shaped flue. A flow equalizer 2 and a plurality of flue gas temperature stabilizing mechanisms 3 for stabilizing the temperature of the high-temperature flue gas are arranged in sequence from top to bottom inside the left side of the U-shaped flue, and a heat exchange mechanism 7 for generating stable superheated or saturated steam is arranged inside the right side of the U-shaped flue.

[0027] In this embodiment, the flue gas temperature stabilization device can stabilize the high temperature flue gas of 200℃~1100℃ to 450℃~650℃, and the heat exchange mechanism 7 can absorb the heat of the flue gas and convert the heat into steam. When the device is used, the flue gas enters the U-shaped flue from the high temperature flue gas inlet 1, and passes through a plurality of flue gas temperature stabilization mechanisms 3 and heat exchange mechanisms 7 for stabilizing the temperature of the high temperature flue gas in sequence to generate stable superheated or saturated steam, which is discharged from the high temperature flue gas outlet 8 and used for power generation and other projects.

[0028] It should be noted that if steam is used for power generation, stable saturated or superheated steam can improve power generation efficiency. The high-temperature fluctuating dust-containing flue gas waste heat recovery device of the utility model can generate stable superheated or saturated steam, which can improve power generation efficiency.

[0029] In one embodiment, the smoke temperature stabilizing mechanism 3 is a plate-type, cylindrical or honeycomb structure, preferably a honeycomb structure, which can increase the heat exchange area between the smoke and the smoke stabilizing mechanism.

[0030] In this embodiment, the flue gas temperature stabilization mechanism 3 is made of magnesia bricks, concrete or cast iron as a whole; or the flue gas temperature stabilization mechanism 3 includes a shell and a high-temperature phase change material filled inside the shell, the shell is made of 304 stainless steel or 347H stainless steel, and the high-temperature phase change material is a chloride phase change material or a carbonate phase change material.

[0031] After the high-temperature fluctuating dusty flue gas passes through the flue gas temperature stabilization mechanism 3, the temperature difference is significantly reduced. For example, taking a process length of 20m as an example, the temperature difference of the high-temperature fluctuating dusty flue gas can be reduced from the original large temperature difference of 900°C to within 200°C.

[0032] In one embodiment, the heat exchange medium of the heat exchange mechanism 7 is water, and the heat exchange mechanism 7 is provided with a superheater, an evaporator and an economizer from bottom to top.

[0033] In another embodiment, the heat exchange medium of the heat exchange mechanism 7 is molten salt, and the heat exchange mechanism 7 is provided with a flue gas molten salt heat exchanger and a steam generator from bottom to top. In this embodiment, the steam generator is a water steam generator.

[0034] In an optional embodiment, the ash handling mechanism includes a bracket 4, at least two ash hoppers 5 and an ash conveyor 6 arranged under each ash hopper 5, the bracket 4 is fixedly connected under the U-shaped flue, the inlet of the ash hopper 5 is connected to the lower side of the U-shaped flue, and the ash conveyor 6 is connected to the outlet of the ash hopper 5.

[0035] In this embodiment, two ash hoppers 5 are specifically provided, which are respectively located below the flue on the left and right sides of the U-shaped flue. The ash hopper 5 is used to receive the ash falling from the U-shaped flue, and the ash conveyor 6 is used to discharge the ash in the ash hopper 5. The ash conveyor 6 in this embodiment can be, but is not limited to, a scraper conveyor or a screw conveyor.

[0036] In one embodiment, the high-temperature fluctuating dusty flue gas waste heat recovery device is further provided with a cleaning mechanism for cleaning the flue gas temperature stabilizing mechanism 3 and the heat exchange mechanism 7 by using shock waves or vibration. The cleaning mechanism can prevent the flue gas temperature stabilizing mechanism 3 and the heat exchange mechanism 7 from reducing the temperature stabilizing efficiency or heat exchange efficiency due to dust.

[0037] In one embodiment, the flow equalizer 2 is a flow guide plate or a flow equalizer. The function of the flow equalizer 2 is to disperse the high-temperature flue gas entering the U-shaped flue from the high-temperature flue gas inlet 1 so that the high-temperature flue gas is fully in contact with the flue gas temperature stabilization mechanism 3.

[0038] The above-mentioned embodiments only express several implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, and these all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model shall be based on the attached claims.

Claims

1. A high-temperature fluctuating dusty flue gas waste heat recovery device, characterized in that: It includes a vertical U-shaped flue and a smoke ash handling mechanism located below the U-shaped flue; A high-temperature flue gas inlet (1) is provided at the top of the left side of the U-shaped flue, and a high-temperature flue gas outlet (8) is provided at the top of the right side of the U-shaped flue; A flow equalizer (2) and a plurality of flue gas temperature stabilizing mechanisms (3) for stabilizing the temperature of high-temperature flue gas are sequentially arranged inside the left side of the U-shaped flue from top to bottom; A heat exchange mechanism (7) for generating stable superheated or saturated steam is arranged inside the right side of the U-shaped flue.

2. A high-temperature fluctuating dusty flue gas waste heat recovery device according to claim 1, characterized in that: The flue gas temperature stabilizing mechanism (3) is a plate-type, cylindrical or honeycomb structure; The flue gas temperature stabilizing mechanism (3) is entirely made of magnesia bricks, concrete or cast iron; or The flue gas temperature stabilization mechanism (3) comprises a shell and a high-temperature phase change material filled in the shell, the shell is made of 304 stainless steel or 347H stainless steel, and the high-temperature phase change material is a chloride phase change material or a carbonate phase change material.

3. A high-temperature fluctuating dusty flue gas waste heat recovery device according to claim 2, characterized in that: The heat exchange medium of the heat exchange mechanism (7) is water, and the heat exchange mechanism (7) is provided with a superheater, an evaporator and an economizer from bottom to top.

4. A high-temperature fluctuating dusty flue gas waste heat recovery device according to claim 2, characterized in that: The heat exchange medium of the heat exchange mechanism (7) is molten salt, and the heat exchange mechanism (7) is provided with a flue gas molten salt heat exchanger and a steam generator from bottom to top.

5. A high-temperature fluctuating dusty flue gas waste heat recovery device according to claim 3 or 4, characterized in that: The ash handling mechanism comprises a bracket (4), at least two ash hoppers (5) and an ash conveyor (6) arranged below each ash hopper (5); the bracket (4) is fixedly connected below the U-shaped flue; the inlet of the ash hopper (5) is connected to the lower side of the U-shaped flue; and the ash conveyor (6) is connected to the outlet of the ash hopper (5).

6. A high-temperature fluctuating dusty flue gas waste heat recovery device according to claim 5, characterized in that: The high-temperature fluctuating dust-containing flue gas waste heat recovery device is also provided with a cleaning mechanism for cleaning the flue gas temperature stabilization mechanism (3) and the heat exchange mechanism (7) by using shock waves or vibration.

7. A high-temperature fluctuating dusty flue gas waste heat recovery device according to claim 6, characterized in that: The flow equalizing element (2) is a flow guide plate or a flow equalizer.

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