Waste heat recovery device for rotary cement kiln

Abstract

The utility model relates to the technical field of rotary cement kilns, in particular to a rotary cement kiln waste heat recovery device which comprises a tank body, a purification box and an air inlet pipe. An annular cavity is formed in the tank body, two spiral plates coaxial with the annular cavity are arranged in the annular cavity, so that the annular cavity is divided into a spiral channel A and a spiral channel B through the two spiral plates, a water inlet pipe, a water outlet pipe, an air guide pipe A and an air guide pipe B are arranged on the tank body, and the water inlet pipe and the water outlet pipe are communicated with the corresponding ends of the spiral channel A respectively. The air guide pipe A and the air guide pipe B are respectively communicated with the corresponding ends of the spiral channel B; the purifying box is arranged on the tank body, a filtering bin and a medicine storage bin are arranged in the purifying box, the air guide pipe A is communicated with the output end of the filtering bin, the air guide pipe B is communicated with the input end of the medicine storage bin, and an exhaust pipe is arranged on the purifying box; the air inlet pipe is communicated with the input end of the filtering bin. Hot air and water flow are opposite in direction, the contact area is large, heat exchange between water and the hot air is promoted, and the water is automatically guided out after being heated.

Description

Technical Field

[0001] This utility model relates to the field of cement rotary kiln technology, and in particular to a waste heat recovery device for cement rotary kilns. Background Technology

[0002] The cement rotary kiln calcines cement raw materials (a mixture of limestone, clay, etc.) at high temperatures (about 1450°C), causing a physicochemical reaction to produce cement clinker (the main components of which are tricalcium silicate, dicalcium silicate, etc.). A large amount of heat is generated during this stage. If it is discharged directly, it will result in a waste of thermal energy. Therefore, it is necessary to recover and utilize the residual heat.

[0003] Chinese patent CN218764631U discloses a waste heat recovery and reuse device for cement rotary kilns. This device, through the coordinated use of a base plate, support frame, insulation box, box body, circulation pipe, water tank, motor, stirring rod, liquid level sensor, temperature sensor, water outlet pipe, first solenoid valve, filter box, purification box, fan, exhaust hood, activated carbon adsorption plate, filter screen, air inlet pipe, and air outlet pipe, solves the problems of existing cement rotary kiln waste heat recovery and reuse devices, which mostly heat water. However, once the water absorbs heat and its temperature rises, it stops absorbing heat, reducing the utilization rate of waste heat. Furthermore, these devices struggle to filter harmful substances in the exhaust gas, potentially causing harm to the environment and operators, thus reducing the practicality of the device.

[0004] However, the device still has shortcomings: the contact area between the inner wall of the hot air flow channel and the surface of the water tank is small, resulting in low heat exchange efficiency. Furthermore, the water in the device lacks a partition structure, causing the water temperature to be uniform throughout. This leads to a significant heat loss after the hot air absorbs heat, and the higher the water temperature, the lower the heat exchange efficiency. Utility Model Content

[0005] The purpose of this invention is to address the problems existing in the background technology by proposing a waste heat recovery device for cement rotary kilns.

[0006] The technical solution of this utility model is as follows: A waste heat recovery device for a cement rotary kiln includes a tank body, an annular cavity coaxial with the tank body, and two spiral plates coaxial with the annular cavity, which divide the annular cavity into coaxial but non-communicating spiral channels A and B through the two spiral plates. The tank body is provided with a water inlet pipe, a water outlet pipe, an air guide pipe A and an air guide pipe B, wherein the water inlet pipe and the water outlet pipe are respectively connected to the corresponding ends of the spiral channel A, and the air guide pipe A and the air guide pipe B are respectively connected to the corresponding ends of the spiral channel B.

[0007] The purification box is installed on the tank body. Inside the purification box, there is a filter chamber with a filter assembly and a medicine storage chamber for storing liquid medicine. The end of the air guide pipe A away from the tank body is connected to the output end of the filter chamber, and the end of the air guide pipe B away from the tank body is connected to the input end of the medicine storage chamber. An exhaust pipe is installed on the purification box at the output end of the medicine storage chamber.

[0008] And the air intake pipe, which is installed on the purification box and connected to the input end of the filter chamber.

[0009] Preferably, a support base is provided at the bottom of the tank.

[0010] Preferably, a flow valve is installed on the outlet pipe to control the internal flow rate and its on / off state.

[0011] Preferably, the water flows from top to bottom in spiral channel A, and the gas flows from bottom to top in spiral channel B.

[0012] Preferably, the filter assembly includes a sealing frame and an activated carbon pack. One end of the sealing frame is inserted into the filter chamber and slidably connected to the purification box. The sealing frame is located between the air inlet pipe and the air guide pipe A. A through hole is provided on the sealing frame. A filter screen is provided inside the lower opening of the through hole, and the activated carbon pack is located inside the through hole and falls on the filter screen.

[0013] Preferably, a one-way valve is installed on the air guide pipe B to prevent the liquid medicine in the medicine storage chamber from flowing back into the spiral channel B.

[0014] Preferably, the purification box is equipped with a dosing pipe and a discharging pipe that are connected to the drug storage compartment. The dosing pipe is equipped with a solenoid valve A that controls the on / off state of its internal components, and the discharging pipe is equipped with a solenoid valve B that controls the on / off state of its internal components.

[0015] Preferably, the purification box is provided with a rotating shaft that is rotatably connected to it. The two ends of the rotating shaft are respectively inserted into the filter chamber and the drug storage chamber. A stirring paddle is provided at the end of the rotating shaft inserted into the drug storage chamber, and an impeller is provided at the end of the rotating shaft inserted into the filter chamber. The inlet of the air inlet pipe is offset from the axis of the rotating shaft and faces the blades of the impeller.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects:

[0017] By setting up spiral channels A and B, which are not interconnected, water and air flow separately in opposite directions within each channel. This allows for continuous heat exchange between the water and the hot air during the continuous flow, with the water temperature at the inlet being significantly lower than the water temperature at the outlet, and the air temperature at the outlet being significantly higher than the air temperature at the inlet. This effectively improves heat exchange efficiency and results in high heat recovery efficiency. Furthermore, by installing filter components and a chemical storage chamber inside the purification chamber, solid impurities are filtered out before the gas enters the spiral channels to prevent blockage. After heat exchange, the gas is then absorbed by the chemical agents to remove harmful substances before being discharged. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of one embodiment of the present utility model;

[0019] Figure 2 This is a schematic diagram of the internal structure of the tank;

[0020] Figure 3 This is a schematic diagram of the internal structure of the purification chamber.

[0021] Reference numerals in the attached diagram: 1. Tank body; 2. Support base; 101. Spiral channel A; 102. Spiral channel B; 3. Spiral plate; 4. Inlet pipe; 5. Outlet pipe; 51. Flow valve; 6. Air guide pipe A; 7. Air guide pipe B; 8. Purification box; 81. Filter chamber; 82. Drug storage chamber; 9. Air inlet pipe; 10. Sealing frame; 11. Activated carbon bag; 12. Exhaust pipe; 13. Rotating shaft; 14. Agitator; 15. Impeller; 16. Dosing pipe; 17. Discharge pipe. Detailed Implementation

[0022] Example 1

[0023] like Figures 1-3As shown, this utility model proposes a waste heat recovery device for a cement rotary kiln, comprising a tank 1, a purification chamber 8, and an air inlet pipe 9. A support base 2 is provided at the bottom of the tank 1. An annular cavity coaxial with the tank 1 is provided inside the tank 1. Two coaxial spiral plates 3 are installed within the annular cavity to divide it into coaxial but non-communicating spiral channels A101 and B102. The spiral plates 3 are, but are not limited to, stainless steel heat-conducting plates. A water inlet pipe 4, a water outlet pipe 5, and an air guide pipe A6 and B7 are provided on the tank 1. The water inlet pipe 4 and the water outlet pipe 5 are respectively connected to the corresponding ends of the spiral channel A101. A flow valve 51 is installed on the water outlet pipe 5 to control its internal flow rate and on / off state. The air guide pipes A6 and B7 are respectively connected to the corresponding ends of the spiral channel B102. The water flow direction in the spiral channel A101 is from top to bottom, and the gas flow direction in the spiral channel B102 is from bottom to top. A one-way valve is installed on the gas duct B7 to prevent the liquid medicine in the storage chamber 82 from flowing back into the spiral channel B102. The one-way valve can control both gas and liquid. A valve clearly marked "dual-purpose gas and liquid" and passing the sealing test (leakage rate ≤ 0.01% of rated flow) is selected and installed strictly according to the characteristics of the medium. The purification box 8 is installed on the tank 1. The purification box 8 is equipped with a filter chamber 81 with a filter assembly and a storage chamber 82 containing liquid medicine. The end of the gas duct A6 away from the tank 1 is connected to the output end of the filter chamber 81, and the end of the gas duct B7 away from the tank 1 is connected to the input end of the storage chamber 82. An exhaust pipe 12 is installed on the purification box 8 at the output end of the storage chamber 82. The filter assembly includes a sealing frame 10 and an activated carbon pack 11. One end of the sealing frame 10 is inserted into the filter chamber 81 and slidably connected to the purification box 8. A through hole is provided on the sealing frame 10, and a filter screen is placed inside the lower opening of the through hole. The activated carbon pack 11 is located inside the through hole and rests on the filter screen. The purification box 8 is equipped with a dosing pipe 16 and a discharging pipe 17, both connected to the drug storage chamber 82. A solenoid valve A controls the on / off state of the dosing pipe 16, and a solenoid valve B controls the on / off state of the discharging pipe 17. An air inlet pipe 9 is located on the purification box 8 and connected to the input end of the filter chamber 81. The sealing frame 10 is located between the air inlet pipe 9 and the air guide pipe A6.

[0024] In this embodiment, firstly, the flow valve 51 is closed, and water is injected downwards along the inlet pipe 4 until the spiral channel A101 is full of water. Then, the hot gas in the rotary kiln enters the inlet pipe 9 through the hot gas pipe. After the hot gas passes through the activated carbon bag and the filter screen to absorb impurities, it rises from below the spiral channel B102 along the guide pipe A6 and enters the drug storage chamber 82 through the guide pipe B7. The residual harmful substances in the gas are absorbed by the chemical agent. Finally, the exhaust gas is discharged along the exhaust pipe 12. During this process, the hot gas exchanges heat with the water, and the water temperature rises. At this time, the flow valve 51 is opened and water is continuously injected into the inlet pipe 4, and the spiral channel A101 is always full of water. The downward water gradually exchanges heat with the increasingly hot gas, so that its temperature will become higher and higher when it is discharged, while the temperature of the upward gas will become lower and lower until it is discharged. When it is necessary to adjust the temperature of the discharged water, the passage diameter of the flow valve 51 can be adjusted to adjust the water flow speed.

[0025] Example 2

[0026] like Figure 3 As shown, the waste heat recovery device for a cement rotary kiln proposed in this utility model, compared with the first embodiment, has a rotating shaft 13 rotatably connected to the purification box 8. The two ends of the rotating shaft 13 are respectively inserted into the filter chamber 81 and the storage chamber 82. A stirring paddle 14 is installed at one end of the rotating shaft 13 inserted into the storage chamber 82, and an impeller 15 is installed at one end of the rotating shaft 13 inserted into the filter chamber 81. The inlet of the air inlet pipe 9 is offset from the axis of the rotating shaft 13 and faces the blades of the impeller 15.

[0027] In this embodiment, the gas entering the filter chamber 81 through the air inlet pipe 9 drives the impeller 15 to rotate, thereby driving the rotating shaft 13 and the stirring paddle 14 to rotate, which in turn stirs the liquid medicine in the medicine storage chamber 82, improving the chemical reaction efficiency or absorption efficiency of the medicine on the harmful components mixed in the gas inside.

[0028] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A waste heat recovery device for a cement rotary kiln, characterized in that, include: Tank (1), with an annular cavity coaxial with it inside the tank (1), and two spiral plates (3) coaxial with it inside the annular cavity, so that the annular cavity is divided into a coaxial but non-conductive spiral channel A (101) and a spiral channel B (102) by the two spiral plates (3). A water inlet pipe (4), a water outlet pipe (5), an air guide pipe A (6) and an air guide pipe B (7) are provided on the tank (1). The water inlet pipe (4) and the water outlet pipe (5) are respectively connected to the corresponding ends of the spiral channel A (101), and the air guide pipe A (6) and the air guide pipe B (7) are respectively connected to the corresponding ends of the spiral channel B (102). Purification box (8) is set on tank (1). The purification box (8) is equipped with a filter chamber (81) with filter components and a medicine storage chamber (82) storing medicine liquid. The end of the air guide pipe A (6) away from the tank (1) is connected to the output end of the filter chamber (81). The end of the air guide pipe B (7) away from the tank (1) is connected to the input end of the medicine storage chamber (82). An exhaust pipe (12) is set on the purification box (8) at the output end of the medicine storage chamber (82). And an air inlet pipe (9), which is installed on the purification box (8) and connected to the input end of the filter chamber (81).

2. The waste heat recovery device for a cement rotary kiln according to claim 1, characterized in that, A support base (2) is provided at the bottom of the tank (1).

3. The waste heat recovery device for a cement rotary kiln according to claim 1, characterized in that, A flow valve (51) is installed on the water outlet pipe (5) to control the internal flow rate and the on / off state.

4. The waste heat recovery device for a cement rotary kiln according to claim 1, characterized in that, The water flows from top to bottom in spiral channel A (101), and the gas flows from bottom to top in spiral channel B (102).

5. The waste heat recovery device for a cement rotary kiln according to claim 1, characterized in that, The filter assembly includes a sealing frame (10) and an activated carbon bag (11). One end of the sealing frame (10) is inserted into the filter chamber (81) and slidably connected to the purification box (8). The sealing frame (10) is located between the air inlet pipe (9) and the air guide pipe A (6). A through hole is provided on the sealing frame (10). A filter screen is provided inside the lower opening of the through hole, and the activated carbon bag (11) is located inside the through hole and falls on the filter screen.

6. The waste heat recovery device for a cement rotary kiln according to claim 1, characterized in that, A one-way valve is installed on the air duct B(7) to prevent the liquid medicine in the medicine storage chamber (82) from flowing back into the spiral channel B(102).

7. The waste heat recovery device for a cement rotary kiln according to claim 1, characterized in that, The purification box (8) is equipped with a dosing pipe (16) and a discharging pipe (17) that are connected to the drug storage chamber (82). The dosing pipe (16) is equipped with a solenoid valve A that controls the opening and closing of its internal parts, and the discharging pipe (17) is equipped with a solenoid valve B that controls the opening and closing of its internal parts.

8. The waste heat recovery device for a cement rotary kiln according to claim 1, characterized in that, A rotating shaft (13) is provided on the purification box (8) and is rotatably connected thereto. The two ends of the rotating shaft (13) are inserted into the filter chamber (81) and the medicine storage chamber (82) respectively. A stirring paddle (14) is provided at one end of the rotating shaft (13) inserted into the medicine storage chamber (82), and an impeller (15) is provided at one end of the rotating shaft (13) inserted into the filter chamber (81). The inlet of the air inlet pipe (9) is offset from the axis of the rotating shaft (13) and faces the blades of the impeller (15).

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