A rotary furnace waste heat recovery device

Abstract

This utility model provides a rotary kiln waste heat recovery device, relating to the field of rotary kiln waste heat recovery technology. The device includes a kiln body, with a water tank installed on one side. The top of the water tank has an inner groove, an annular groove one, and an annular groove two. The annular groove one is located outside the inner groove, and the annular groove two is located outside the annular groove one. A spiral heat exchange tube is installed inside the annular groove one, with one end of the heat exchange tube fixedly connected to a condensing pipe. The condensing pipe is fixedly connected to the top of the kiln body. This rotary kiln waste heat recovery device significantly improves heat exchange efficiency by incorporating the inner groove, annular groove one, and annular groove two within the water tank. The spiral heat exchange tube is placed in the annular groove one and is 360° surrounded by the heat-conducting liquid between the annular groove two and the inner groove, increasing the heat exchange area by 5 to 8 times, thereby effectively improving the waste heat recovery efficiency of the rotary kiln waste heat recovery device.

Description

Technical Field

[0001] This utility model relates to a rotary kiln waste heat recovery device, specifically a rotary kiln waste heat recovery device, belonging to the field of rotary kiln waste heat recovery technology. Background Technology

[0002] Rotary kilns, as a conventional type of kiln, have existed for over a century, but they are all large or super-large, mainly used for the primary rough processing of powder or mineral materials, such as in the firing and calcination of cement clinker; the preparation of titanium dioxide from kaolin; and the processing of rare earth materials. Rotary kiln waste heat recovery devices are equipment used to recover the heat energy lost by rotary kilns (such as cement rotary kilns, metallurgical rotary kilns, etc.) during the production process, aiming to improve energy utilization efficiency, reduce energy consumption, and reduce carbon emissions.

[0003] Extensive searches revealed the following: Chinese Utility Model Patent Announcement No. CN106949490A: A waste heat recovery device for a solid waste rotary kiln. The device comprises a feed inlet on the left side of the kiln body, a slag outlet on the right side, a burner inside the kiln body, a recovery pipe above the burner, a condensation pipe above the recovery pipe, and the condensation pipe wrapped around a water tank; a blower is installed between the recovery pipe and the condensation pipe.

[0004] Existing rotary kilns for solid waste incineration emit large amounts of high-temperature flue gas (600-900°C) per hour. Current waste heat recovery methods involve directly winding condenser pipes around the outer wall of a cylindrical water tank, relying on line contact between the pipe and tank walls for heat exchange. The drawbacks are: small contact area, insufficient heat exchange area, and a waste heat recovery rate of only about 30%; furthermore, the space between the pipe and tank walls is mostly air gaps, resulting in high thermal resistance and significant heat loss, thus reducing the overall waste heat recovery efficiency of the rotary kiln waste heat recovery device. Summary of the Invention

[0005] (a) Technical problems to be solved The purpose of this invention is to provide a rotary kiln waste heat recovery device to solve the above-mentioned problems, thereby addressing the issue of low waste heat recovery efficiency in existing rotary kiln waste heat recovery devices.

[0006] (II) Technical Solution This utility model is achieved through the following technical solution: a rotary kiln waste heat recovery device, including a furnace body, a water tank installed on one side of the furnace body, an inner groove, an annular groove one and an annular groove two are opened on the top of the water tank, the annular groove one is located outside the inner groove, the annular groove two is located outside the annular groove one, a heat exchange tube with a spiral structure is arranged in the annular groove one, one end of the heat exchange tube is fixedly connected to a condensing pipe, and the condensing pipe is fixedly connected to the top of the furnace body.

[0007] Preferably, the condensation pipe includes two connecting pipes, and a filter box is fixedly connected between the two connecting pipes. The filter box is equipped with a blower and two filter plates.

[0008] Preferably, the top of the filter box has an inspection port, and a cover plate is adapted to fit inside the inspection port. The cover plate is adapted to fit the inspection port. Linearly arrayed grooves are formed on both inner walls of the filter box. A first wire plate is fixedly sleeved on the outside of the blower. A second wire plate is fixedly connected to both sides of the filter plate. The first wire plate and the second wire plate are slidably connected to the corresponding grooves inside.

[0009] Preferably, the inspection port includes a coarse groove and a fine groove that are interconnected. The cover plate is adapted to the coarse groove, and a sealing ring is fixedly connected to the bottom of the cover plate. Four fixing plates arranged in a circumferential array are fixedly connected to the outside of the cover plate. A through-type fixing port is opened on the fixing plate, and a bolt is installed in the fixing port. A threaded groove is opened at the corresponding position of each fixing port of the filter box, and the bottom end of the bolt is threadedly connected to the threaded groove.

[0010] Preferably, the water tank is provided with an inlet pipe, an outlet pipe and a flue pipe on one side. The inlet pipe and the outlet pipe are both connected to the annular groove. The flue pipe is fixedly connected to the end of the heat exchange pipe away from the condenser pipe. A solenoid valve is provided on the inlet pipe, the outlet pipe and the flue pipe.

[0011] Preferably, an inlet pipe and an outlet pipe are respectively provided on the top and one side of the water tank, and both the inlet pipe and the outlet pipe are connected to the annular groove. Solenoid valves are provided on both the inlet pipe and the outlet pipe.

[0012] Preferably, a plurality of connecting pipes are fixedly connected between the second annular groove and the inner groove, and the connecting pipes are located inside the first annular groove.

[0013] Preferably, the condensate pipe is fitted with an insulation layer on the outside, and the water tank is coated with a heat-insulating coating on the outside.

[0014] This utility model provides a waste heat recovery device for a rotary kiln, which has the following beneficial effects: 1. The waste heat recovery device for rotary kilns significantly improves heat exchange efficiency by setting an inner tank, annular tank one, and annular tank two in the water tank. The spiral heat exchange tube is placed in annular tank one and is surrounded 360° by the heat-conducting liquid between annular tank two and the inner tank, increasing the heat exchange area by 5 to 8 times, thereby effectively improving the waste heat recovery efficiency of the rotary kiln waste heat recovery device.

[0015] 2. This rotary kiln waste heat recovery device, by setting up a filter box, with the side-pluggable filter plate of the filter box modularly installed with the blower and the cover plate bolted, effectively improves the convenience and efficiency of disassembly and maintenance of the blower and filter plate, and at the same time, it can also improve the sealing performance of the filter plate. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the entire utility model; Figure 2 This is a three-dimensional cross-sectional view of the water tank of this utility model; Figure 3 This is a three-dimensional schematic diagram of the condensate pipe of this utility model; Figure 4 This is a three-dimensional schematic diagram of the heat exchange tube and connecting tube of this utility model.

[0017] [Explanation of Key Component Symbols] 1. Furnace body; 2. Water tank; 3. Inner groove; 4. Annular groove one; 5. Annular groove two; 6. Condensation pipe; 601. Connecting pipe; 602. Filter box; 603. Blower; 604. Filter plate; 7. Heat exchange tube; 8. Water inlet pipe; 9. Water outlet pipe; 10. Smoke exhaust pipe; 11. Connecting pipe; 12. Cover plate; 13. Cable tray; 14. Bolt; 15. Liquid inlet pipe; 16. Liquid outlet pipe. Detailed Implementation

[0018] This utility model provides a rotary kiln waste heat recovery device.

[0019] For examples, please refer to [link / reference]. Figure 1 , Figure 2 , Figure 3 and Figure 4 The furnace includes a furnace body 1. A water tank 2 is installed on one side of the furnace body 1. The top of the water tank 2 is provided with an inner groove 3, an annular groove 1 4 and an annular groove 2 5. The annular groove 1 4 is located outside the inner groove 3, and the annular groove 2 5 is located outside the annular groove 1 4. A heat exchange tube 7 with a spiral structure is installed in the annular groove 1 4. One end of the heat exchange tube 7 is fixedly connected to a condensing pipe 6, and the condensing pipe 6 is fixedly connected to the top of the furnace body 1. Specifically, the annular tank 4 is filled with a heat-conducting liquid, which can be water or heat-conducting oil, etc., with an operating temperature range of -20℃ to 300℃ and a flash point of ≥200℃. Corrosion inhibitors are added to prevent oxidation of the heat exchange tube 7 and the tank wall. The furnace body 1 is a rotary kiln, which is a prior art equipment. Its specific form, usage and installation method will not be described in detail in this application.

[0020] Specifically, positioning brackets can be evenly distributed along the spiral trajectory on the bottom surface of the annular groove 4. The positioning brackets are high-temperature resistant elastic clips used to maintain a gap of ≥3mm between the heat exchange tube 7 and the inner wall of the annular groove 4 to prevent thermal expansion collision. Specifically, an expansion chamber and an overflow pipe can be provided at the top of the annular tank 4. The expansion chamber is connected to an external expansion tank via the overflow pipe to absorb the thermal expansion volume of the heat transfer liquid. A safety valve can be installed at the top of the annular tank 4, with an opening pressure of 0.4 MPa. The pressure relief outlet is connected in parallel with the exhaust pipe 10 to ensure automatic discharge when the heat transfer liquid is over-pressurized. At the same time, a temperature sensor and a pressure sensor can be installed inside the annular tank 4. The signals of both sensors are connected to the PLC and interlocked with the solenoid valve 2 to realize automatic shut-off of liquid intake in case of over-temperature or over-pressure.

[0021] Please see Figure 1 , Figure 2 and Figure 3 The condenser pipe 6 includes two connecting pipes 601, and a filter box 602 is fixedly connected between the two connecting pipes 601. The filter box 602 is equipped with a blower 603 and two filter plates 604.

[0022] Please see Figure 1 , Figure 2 and Figure 3 The filter box 602 has an inspection port on the top, and a cover plate 12 is fitted inside the inspection port. The cover plate 12 is adapted to the inspection port. Linear array grooves 13 are provided on both inner walls of the filter box 602. A wire plate 1 is fixedly sleeved on the outside of the blower 603. Wire plates 2 are fixedly connected to both sides of the filter plate 604. Wire plates 1 and 2 are slidably connected inside the corresponding wire grooves 13.

[0023] Please see Figure 1 , Figure 2 and Figure 3 The inspection port includes a coarse groove and a fine groove that are interconnected. The cover plate 12 is adapted to the coarse groove, and a sealing ring is fixedly connected to the bottom of the cover plate 12. Four fixing plates arranged in a circumferential array are fixedly connected to the outside of the cover plate 12. A through-type fixing port is opened on the fixing plate, and a bolt 14 is installed in the fixing port. A threaded groove is opened at the corresponding position of each fixing port in the filter box 602, and the bottom end of the bolt 14 is threadedly connected to the threaded groove. Specifically, sealing rings are provided on the outer sides of both wire plate one and wire plate two. The sealing rings increase the sealing between cover plate 12 and inspection port, as well as between the inner wall of wire trough 13 and wire plate one, or between the inner wall of wire trough 13 and wire plate two. At the same time, the sealing rings on wire plate one and wire plate two can also increase the sealing between cover plate 12 and wire plate one, or between cover plate 12 and wire plate two support. The sealing rings are existing technology structures, and their specific form, usage and installation methods will not be described in detail in this application.

[0024] Please see Figure 2 and Figure 4Water tank 2 is provided with an inlet pipe 8, an outlet pipe 9 and a flue pipe 10 on one side. The inlet pipe 8 and the outlet pipe 9 are both connected to the annular groove 2 5. The flue pipe 10 is fixedly connected to the end of the heat exchange tube 7 away from the condenser pipe 6. Solenoid valve 1 is provided on the inlet pipe 8, the outlet pipe 9 and the flue pipe 10. Specifically, the inlet pipe 15 is fixedly connected to the outlet of the high-temperature circulating pump, and the inlet of the high-temperature circulating pump is connected to a water source to deliver room temperature or cooling liquid into the annular tank 5. The outlet pipe 16 can be connected to a plate heat exchanger, and according to the on-site process requirements, the liquid is supplied to the domestic hot water storage tank after secondary heat exchange using the plate heat exchanger. This system is also used for waste heat equipment in the plant area, user heating, or process hot water systems, etc., while the outlet of the plate heat exchanger is connected to a water source, thus forming a water circulation system.

[0025] Please see Figure 2 and Figure 4 The top and one side of the water tank 2 are respectively provided with an inlet pipe 15 and an outlet pipe 16. Both the inlet pipe 15 and the outlet pipe 16 are connected to the annular groove 4. Both the inlet pipe 15 and the outlet pipe 16 are equipped with a solenoid valve 2. Specifically, the annular trough 4 is a "heat-conducting liquid chamber". Its inlet pipe 15 and outlet pipe 16 are responsible for forming a closed-loop system with external heat source equipment or cooling equipment, so as to remove or replenish the heat absorbed by the heat exchange tube 7, and ensure that the waste heat recovery device is always in the optimal operating temperature range.

[0026] Please see Figure 2 Multiple connecting pipes 11 are fixedly connected between the annular groove 2 5 and the inner groove 3, and the connecting pipes 11 are located inside the annular groove 1 4. Specifically, water and ordinary liquids can be injected into annular tank 2 5 without the need to add corrosion inhibitors, while annular tank 1 4 needs to be filled with heat-conducting liquid and corrosion inhibitors added. This forms a primary heat exchange zone and a secondary heat exchange zone, reducing the amount of corrosion inhibitors used and the heat exchange cost.

[0027] Please see Figure 1 The condenser pipe 6 is fitted with an insulation layer on the outside, and the water tank 2 is coated with a heat insulation coating on the outside. Specifically, the insulation layer has a double-layer structure: an inner layer of aluminum silicate fiber blanket, an outer layer of polyurethane foam, and an overall outer cover of color steel shell. The joints of the shell are sealed with stainless steel self-tapping screws and weather-resistant adhesive. The heat insulation coating is a ceramic microsphere reflective heat insulation paint. Specifically, the temperature and pressure sensors, PLC, high-temperature circulating pump, and plate heat exchanger are all existing technologies, and their specific forms, usage methods, and installation methods are all existing technologies, which will not be elaborated in this application.

[0028] Working principle: The high-temperature flue gas generated by the furnace body 1 is transported to the heat exchange tube 7 through the condenser pipe 6. Along the way, it is pressurized by the filter box 602 and the blower 603, and dust is removed by the filter plate 604. Finally, it is discharged from the exhaust pipe 10. Cold water enters the annular tank 2 5 through the inlet pipe 8, absorbs the heat from the heat-conducting liquid in the annular tank 1 4, and is then sent to the heat-using end through the outlet pipe 9. Heat transfer fluid circulation: The heat transfer fluid fills the annular tank 4 through the inlet pipe 15, and quickly transfers the heat of the heat exchange tube 7 to the water in the annular tank 5 and the inner tank 3; after the temperature rises, it can be forced to circulate or naturally circulate through the outlet pipe 16 to maintain a constant temperature.

[0029] Control logic: Solenoid valve 1 regulates the inlet and outlet water flow, and solenoid valve 2 regulates the flow rate of the heat transfer liquid; multiple sets of connecting pipes 11 form parallel high flow or series high temperature difference modes under different valve openings, so as to achieve optimal utilization of waste heat when the rotary kiln load changes.

[0030] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A rotary kiln waste heat recovery device, comprising a kiln body (1), characterized in that: A water tank (2) is installed on one side of the furnace body (1). The top of the water tank (2) is provided with an inner groove (3), an annular groove one (4) and an annular groove two (5). The annular groove one (4) is located outside the inner groove (3), and the annular groove two (5) is located outside the annular groove one (4). A heat exchange tube (7) with a spiral structure is provided in the annular groove one (4). One end of the heat exchange tube (7) is fixedly connected to a condensing pipe (6), and the condensing pipe (6) is fixedly connected to the top of the furnace body (1).

2. A rotary furnace waste heat recovery device according to claim 1, characterized in that: The condensation pipe (6) includes two connecting pipes (601), and a filter box (602) is fixedly connected between the two connecting pipes (601). A blower (603) and two filter plates (604) are installed in the filter box (602).

3. A rotary furnace waste heat recovery device according to claim 2, characterized in that: The filter box (602) has an inspection port on the top, and a cover plate (12) is fitted inside the inspection port. The cover plate (12) is adapted to the inspection port. Linear array grooves (13) are provided on both sides of the inner wall of the filter box (602). A wire plate one is fixedly sleeved on the outside of the blower (603). A wire plate two is fixedly connected to both sides of the filter plate (604). The wire plate one and the wire plate two are slidably connected inside the corresponding wire grooves (13).

4. A rotary furnace waste heat recovery device according to claim 3, characterized in that: The inspection port includes a coarse groove and a fine groove that are interconnected. The cover plate (12) is adapted to the coarse groove, and a sealing ring is fixedly connected to the bottom of the cover plate (12). Four fixing plates in a circumferential array are fixedly connected to the outside of the cover plate (12). A through-type fixing port is opened on the fixing plate, and a bolt (14) is provided in the fixing port. A threaded groove is opened at the corresponding position of each fixing port of the filter box (602), and the bottom end of the bolt (14) is threadedly connected to the threaded groove.

5. A rotary furnace waste heat recovery device according to claim 1, characterized in that: The water tank (2) is provided with an inlet pipe (8), an outlet pipe (9) and a flue pipe (10) on one side. The inlet pipe (8) and the outlet pipe (9) are connected to the annular groove (5). The flue pipe (10) is fixedly connected to the end of the heat exchange pipe (7) away from the condenser pipe (6). The inlet pipe (8), the outlet pipe (9) and the flue pipe (10) are all equipped with a solenoid valve.

6. A rotary furnace waste heat recovery device according to claim 2, characterized in that: The water tank (2) is provided with an inlet pipe (15) and an outlet pipe (16) on the top and one side respectively. The inlet pipe (15) and the outlet pipe (16) are both connected to the annular groove (4). Solenoid valves are provided on the inlet pipe (15) and the outlet pipe (16).

7. A rotary furnace waste heat recovery device according to claim 4, characterized in that: Multiple connecting pipes (11) are fixedly connected between the second annular groove (5) and the inner groove (3), and the connecting pipes (11) are located inside the first annular groove (4).

8. A rotary furnace waste heat recovery device according to claim 4, characterized in that: The condenser pipe (6) is fitted with an insulation layer on the outside, and the water tank (2) is coated with a heat insulation coating on the outside.

Images