Precious metal smelting furnace with waste heat recovery function

Abstract

The invention belongs to the technical field of waste heat recovery of smelting furnaces, and discloses a precious metal smelting furnace with a waste heat recovery function, which comprises a smelting furnace, the smelting furnace comprises a shell, a crucible and a heat insulation cover, the crucible and the heat insulation cover are mounted in the shell, the crucible is positioned in the heat insulation cover, a bracket is hinged to the shell, and the precious metal smelting furnace further comprises a heat exchanger which is mounted in the heat insulation cover and stores purified water; according to the scheme, metal in the crucible is heated through the coil, heat is dissipated to heat purified water in the heat exchanger, generated steam can enter the pressure tank to be stored, and an operator presses the spring combined core rod to enable the transverse cavity to communicate the first pipeline with the second pipeline; the output end of the tension spring combined telescopic piston rod can push the shell to drive the crucible to slowly rotate around the shaft on the support, so that metal liquid in the crucible is poured out, part of heat in waste heat is collected and converted into a power source used for driving the crucible to subsequently pour precious metal liquid, electric power is saved, and meanwhile the shell can be stably driven to rotate.

Description

Technical Field

[0001] This invention belongs to the field of waste heat recovery technology of smelting furnaces, specifically a precious metal smelting furnace with waste heat recovery function. Background Technology

[0002] Precious metal melting and shaping refers to the process of melting and casting highly purified gold, silver, and platinum group metals at high temperatures into a final product of a specific shape.

[0003] When smelting high-purity precious metals, a medium-frequency induction furnace is typically used. The weighed metal is placed in a crucible, and a medium-frequency alternating current is passed through a coil wound around the crucible. This induces a current within the metal. Due to the inherent resistance of the metal, when the strong induced current flows through it, it generates significant heat by overcoming this resistance, thus melting the precious metal in the crucible. For precious metals other than gold (which can be directly exposed to air for smelting), the crucible is usually sealed with a lid before an inert gas is introduced for smelting.

[0004] When smelting precious metals in industrial batches, the smelting time for tens of kilograms of metal is usually several minutes. After smelting, the power to the coil needs to be stopped. At this time, the crucible needs to be rotated (manually rotated handle or driven by motor) to pour out the molten precious metal. Under such short working conditions, it is difficult to continuously and stably collect and utilize the heat lost by such small-volume smelting furnaces (usually by heating water for heating or power generation, etc.), resulting in low actual benefits of waste heat recovery. Therefore, the heat lost by the smelting furnace is usually allowed to diffuse outward on its own rather than adding an additional waste heat recovery mechanism.

[0005] Although the heat lost from the smelting furnace is not subject to additional waste heat recovery mechanisms due to low recovery efficiency and is allowed to dissipate naturally, some of this waste heat can still be collected and converted into a power source to drive the subsequent pouring of molten precious metals from the crucible. Therefore, to achieve the above effect, a precious metal smelting furnace with waste heat recovery function is proposed. Summary of the Invention

[0006] To address the problems mentioned in the background art, the present invention provides a precious metal smelting furnace with waste heat recovery function, which solves the problem that the waste heat recovery efficiency of small smelting furnaces is low and the heat generated is allowed to diffuse outward on its own and be wasted.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a precious metal smelting furnace with waste heat recovery function, comprising a smelting furnace, which includes an outer shell, a crucible installed therein and a heat insulation cover, wherein the crucible is located in the heat insulation cover, a bracket is hinged on the outer shell, and further comprising: a heat exchanger installed in the heat insulation cover and storing pure water, a pressure tank connected to the top of the heat exchanger is installed at the bottom of the outer shell, and a drive mechanism is installed at the top of the bracket;

[0008] The driving mechanism includes a tension spring combined telescopic piston rod hinged to the top of the bracket, and the output end of the tension spring combined telescopic piston rod is hinged to the outer shell. A sleeve is fixedly connected to the top of the bracket, and a spring combined core rod is movably sleeved inside the sleeve. Pipe 1 and pipe 2 are fixedly connected to the sleeve, and the other ends of pipe 1 and pipe 2 are respectively connected to the tension spring combined telescopic piston rod and the pressure tank. A transverse cavity and a bending cavity are opened on the spring combined core rod. Initially, pipe 1 can be connected to the outside through the bending cavity. At this time, pipe 2 is blocked by the outer periphery of the spring combined core rod. When the transverse cavity moves downward, it can connect pipe 1 and pipe 2. A counterweight is fixedly connected to the bottom of the outer shell.

[0009] Preferably, the weight of the counterweight is greater than the weight of the portion of the housing located above the axis, and the tension spring combined telescopic piston rod can be replaced by a piston telescopic rod.

[0010] Preferably, the diameter of the middle part of the transverse cavity is smaller than the diameter of its two ends.

[0011] Preferably, the heat exchanger includes several heat exchange vertical tubes, heat exchange ring tubes, annular fins, and a set of annular tubes. The heat exchange vertical tubes are arranged in annular array around the outer periphery of the crucible and their bottom ends are installed at the bottom of the heat insulation cover cavity. Several heat exchange ring tubes are vertically and equidistantly arranged on the heat exchange vertical tubes and conduct the heat exchange vertical tubes through each other. Several annular fins are vertically and equidistantly installed around the outer periphery of the heat exchange vertical tubes. The annular tubes are located at the top of the heat exchange vertical tubes and are used to conduct the heat exchange vertical tubes through each other.

[0012] The heat exchange vertical tube contains pure water, and the annular fins at the top are positioned above the pure water surface.

[0013] Preferably, the pressure tank includes a tank body fixed to the bottom of the outer shell cavity and located below the heat insulation cover. An air inlet pipe is fixedly connected to the top of the tank body. The top end of the air inlet pipe extends into the heat insulation cover and communicates with an annular pipe. A one-way valve is provided in the air inlet pipe, which can communicate with the tank body in one direction. One end of the second pipe can extend to the bottom of the cavity of the tank body.

[0014] Preferably, the smelting furnace is equipped with a water replenishment component for replenishing pure water into the heat exchange vertical pipe.

[0015] Preferably, the water replenishment component includes a water storage tank fixedly installed between the bottom of the outer shell and the counterweight, a box body is fixedly connected to the water storage tank, the top of the box body passes through the water storage tank, the outer shell and the heat insulation cover and can be fixedly connected to the annular pipe, and a one-way valve II that can be unidirectionally connected to the annular pipe is installed inside the box body; a water replenishment port is also provided on the top of the water storage tank.

[0016] Preferably, the water inlet on the water storage tank is provided with a one-way membrane flap, which allows gas to enter the water storage tank in one direction.

[0017] Preferably, a pressure relief mechanism is installed on the tank body; the pressure relief mechanism includes a sleeve two fixedly connected to the tank body, and the top end of the sleeve two passes through the tank body and the heat insulation cover. An exhaust pipe located outside the tank body is fixedly connected to the sleeve two, and the other end of the sleeve two can extend to the outside of the outer shell. A spring-piston combination that can initially block one end of the exhaust pipe is movably connected inside the sleeve two, and a hammer end located at the bottom of the heat insulation cover cavity is fixedly connected to the top end of the spring-piston combination.

[0018] When the spring-loaded piston moves upward, it allows the tank to be connected through the sleeve and the exhaust pipe, and at this time, the top of the hammer can strike the bottom of the crucible.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] The above scheme heats the metal inside the crucible with a coil, and the heat emitted heat heats the pure water in the heat exchanger. The generated steam is stored in a pressure tank. After heating is completed, the operator presses the spring combination core rod to open the horizontal cavity to pipe one and pipe two, allowing the gas in the pressure tank to enter the tension spring combination telescopic piston rod and drive the tension spring combination telescopic piston rod to extend. The output end of the tension spring combination telescopic piston rod will push the outer shell to drive the crucible to rotate slowly around the axis on the support, thereby pouring out the molten metal in the crucible. This realizes the collection of part of the residual heat and converts it into a power source to drive the crucible to pour out the precious metal liquid in the future. This saves electricity and can also stably drive the rotation of the outer shell.

[0021] In the above scheme, during the metal smelting process, the gas continuously generated in the heat exchanger is sent into the tank. When the pressure inside the tank is too high, it will push the spring-loaded piston upward and stretch the spring to store energy. When the spring-loaded piston releases the blockage on the exhaust pipe, the gas inside the tank will be discharged out through the exhaust pipe to ensure the stability of the pressure inside the tank. At the same time, during the upward movement of the spring-loaded piston, it will also push the hammer end upward and hit the bottom of the crucible to generate vibration, so as to ensure that the molten metal inside the crucible is uniformly mixed, and can also make the unmelted metal above the liquid metal sink quickly in the liquid surface, thereby improving the smelting efficiency of the metal.

[0022] After the above-mentioned device stops working, the gas temperature inside the heat insulation cover will quickly dissipate outward, causing the temperature inside the heat insulation cover, heat exchange vertical pipe, and heat exchange ring pipe to drop rapidly. At this time, the liquid evaporated in the heat exchange vertical pipe will condense, and the pressure inside the heat exchange vertical pipe will decrease and become negative pressure. The pure water in the water storage tank will be transported to the heat exchange vertical pipe for replenishment through one-way valve two and the tank body, and the pure water will be replenished to the other heat exchange vertical pipes through the heat exchange ring pipe to ensure that the device can continue to work stably. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 This is a schematic diagram of the frontal planar structure of the present invention;

[0025] Figure 3 This is a side cross-sectional view of the present invention;

[0026] Figure 4 This is a side view schematic diagram of the structure of the present invention;

[0027] Figure 5 This is a schematic diagram of the heat exchange mechanism of the present invention;

[0028] Figure 6 This is a partial cross-sectional view of the driving mechanism of the present invention;

[0029] Figure 7 This is a partial cross-sectional view of the pressure vessel of the present invention;

[0030] Figure 8 for Figure 7 Enlarged view of point A in the middle;

[0031] Figure 9 This is a schematic diagram of the furnace body of the present invention.

[0032] In the diagram: 1. Smelting furnace; 11. Outer shell; 111. Support; 112. Counterweight; 12. Crucible; 13. Heat insulation cover; 2. Heat exchanger; 21. Heat exchange vertical pipe; 22. Heat exchange ring pipe; 23. Annular fins; 24. Annular pipe; 3. Pressure tank; 31. Tank body; 32. Air inlet pipe; 33. One-way valve; 4. Drive mechanism; 41. Spring-loaded telescopic piston rod; 42. Sleeve; 43. Spring-loaded core rod; 44. Horizontal cavity; 45. Bending cavity; 46. Pipeline; 47. Pipeline; 5. Water supply assembly; 51. Water storage tank; 511. One-way diaphragm; 52. Box body; 53. One-way valve; 6. Pressure relief mechanism; 61. Sleeve; 62. Spring-loaded piston; 63. Exhaust pipe; 64. Hammer end. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] like Figures 1 to 9 As shown, the present invention provides a precious metal smelting furnace with waste heat recovery function, including a smelting furnace 1, which includes an outer shell 11, a crucible 12 installed therein and a heat insulation cover 13, wherein the crucible 12 is located in the heat insulation cover 13, a bracket 111 is hinged on the outer shell 11, and further includes: a heat exchanger 2 installed in the heat insulation cover 13 and storing pure water, a pressure tank 3 connected to the top of the heat exchanger 2 is installed at the bottom of the outer shell 11, and a drive mechanism 4 is installed at the top of the bracket 111;

[0035] The drive mechanism 4 includes a tension spring combined telescopic piston rod 41 hinged to the top of the bracket 111, and the output end of the tension spring combined telescopic piston rod 41 is hinged to the outer shell 11. A sleeve 42 is fixedly connected to the top of the bracket 111. A spring combined core rod 43 is movably sleeved inside the sleeve 42. A pipe 46 and a pipe 47 are fixedly connected to the sleeve 42. The other ends of pipe 46 and pipe 47 are respectively connected to the tension spring combined telescopic piston rod 41 and the pressure tank 3. A transverse cavity 44 and a bending cavity 45 are opened on the spring combined core rod 43. Initially, pipe 46 can be connected to the outside through the bending cavity 45. At this time, pipe 47 is blocked by the outer periphery of the spring combined core rod 43. When the transverse cavity 44 moves downward, it can connect pipe 46 and pipe 47. A counterweight 112 is fixedly connected to the bottom of the outer shell 11.

[0036] The weight of the counterweight 112 is greater than the weight of the portion of the outer casing 11 located above the axis, so the tension spring combined telescopic piston rod 41 can be replaced by a piston telescopic rod;

[0037] The diameter of the middle part of the transverse cavity 44 is smaller than the diameter of its two ends to reduce the flow of gas that can enter the pipe 46 through the transverse cavity 44 to avoid the rapid extension of the tension spring combined telescopic piston rod 41.

[0038] Using the above scheme, the metal in the crucible 12 is heated by a coil and the heat emitted is used to heat the pure water in the heat exchanger 2. The generated steam will enter the pressure tank 3 for storage. After heating is completed, the operator presses the spring combination core rod 43 to make the horizontal cavity 44 connect the pipe 1 46 and the pipe 2 47, so that the gas in the pressure tank 3 enters the tension spring combination telescopic piston rod 41 and drives the tension spring combination telescopic piston rod 41 to extend. The output end of the tension spring combination telescopic piston rod 41 will push the outer shell 11 to drive the crucible 12 to rotate slowly around the axis on the support 111, thereby pouring out the metal liquid in the crucible 12. This realizes the collection of part of the heat in the waste heat and converts it into a power source for driving the crucible 12 to pour out the precious metal liquid in the future. This saves electricity and can also stably drive the rotation of the outer shell 11.

[0039] Furthermore, after releasing the pressure on the spring assembly core rod 43 and allowing it to reset under its own elastic force, the pipe 46 is connected to the outside through the bending cavity 45. At this time, under the action of the tension of the spring assembly telescopic piston rod 41, the outer shell 11 will be pulled to reset. At this time, the gas and residual liquid in the spring assembly telescopic piston rod 41 will be discharged through the pipe 46 and the bending cavity 45.

[0040] like Figure 3 and Figures 5-8 As shown, the heat exchanger 2 includes several heat exchange vertical tubes 21, heat exchange ring tubes 22, annular fins 23 and a set of annular tubes 24. The heat exchange vertical tubes 21 are arranged in annular array on the outer periphery of the crucible 12 and the bottom end is installed at the bottom of the cavity of the heat insulation cover 13. Several heat exchange ring tubes 22 are vertically and equidistantly arranged on the heat exchange vertical tubes 21 and conduct the heat exchange vertical tubes 21. Several annular fins 23 are vertically and equidistantly arranged on the outer periphery of the heat exchange vertical tubes 21. The annular tubes 24 are located at the top of the heat exchange vertical tubes 21 and are used to conduct the heat exchange vertical tubes 21.

[0041] The heat exchange vertical tube 21 stores pure water, and the annular fins 23 at the top are above the pure water surface; the pressure tank 3 includes a tank body 31 fixed to the bottom of the cavity of the outer shell 11 and located below the heat insulation cover 13. The top of the tank body 31 is fixedly connected to an air inlet pipe 32, the top end of the air inlet pipe 32 extends into the heat insulation cover 13 and connects to the annular pipe 24. A one-way valve 33 that can communicate with the tank body 31 in one direction is provided in the air inlet pipe 32; one end of the second pipe 47 can extend to the bottom of the cavity of the tank body 31.

[0042] Using the above scheme, the metal in the crucible 12 is heated by the coil. The heat emitted from the crucible 12 will heat the pure water in the heat exchange vertical pipe 21 and the heat exchange ring pipe 22. The emitted steam will enter the tank 31 for storage through the ring pipe 24, the air inlet pipe 32 and the one-way valve 33.

[0043] It is worth noting that since the bottom end of pipe 2 47 can extend to the bottom of tank 31, when the drive mechanism 4 is working, the pressure in tank 31 can pump the condensed liquid in tank 31 into the tension spring combined telescopic piston rod 41 through pipe 2 47. When the tension spring combined telescopic piston rod 41 is reset, it can discharge the liquid.

[0044] like Figures 1-5 , Figure 7 and Figure 8 As shown, a water replenishment component 5 for replenishing pure water to the heat exchange vertical pipe 21 is installed on the smelting furnace 1; the water replenishment component 5 includes a water storage tank 51 fixedly installed between the bottom of the outer shell 11 and the counterweight 112, a box body 52 is fixedly connected to the water storage tank 51, the top of the box body 52 passes through the water storage tank 51, the outer shell 11 and the heat insulation cover 13 and can be fixedly connected to the annular pipe 24, and a one-way valve 53 that can be unidirectionally connected to the annular pipe 24 is installed inside the box body 52;

[0045] The top of the water storage tank 51 is also provided with a water inlet; a one-way membrane flap 511 is provided at the water inlet on the water storage tank 51, and gas can enter the water storage tank 51 in one direction through the one-way membrane flap 511.

[0046] Using the above scheme, after the device stops working, the gas temperature inside the heat insulation cover 13 will quickly dissipate outward, causing the temperature inside the heat insulation cover 13, heat exchange vertical pipe 21, and heat exchange ring pipe 22 to drop rapidly. At this time, the liquid evaporated in the heat exchange vertical pipe 21 will condense, causing the pressure inside the heat exchange vertical pipe 21 to decrease and become negative pressure. The pure water in the water storage tank 51 will be unidirectionally transported to the heat exchange vertical pipe 21 through the one-way valve 53 and the tank body 52 for replenishment, and the pure water will be replenished to the other heat exchange vertical pipes 21 through the heat exchange ring pipe 22 to ensure that the device can continue to work stably.

[0047] like Figures 3-5 , Figure 7 and Figure 8 As shown, a pressure relief mechanism 6 is installed on the tank body 31; the pressure relief mechanism 6 includes a sleeve 61 fixedly connected to the tank body 31, and the top end of the sleeve 61 passes through the tank body 31 and the heat insulation cover 13. An exhaust pipe 63 located outside the tank body 31 is fixedly connected to the sleeve 61, and the other end of the sleeve 61 can extend to the outside of the outer shell 11. A spring combination piston 62 that can initially block one end of the exhaust pipe 63 is movably connected inside the sleeve 61. The top end of the spring combination piston 62 is fixedly connected to a hammer end 64 located at the bottom of the cavity of the heat insulation cover 13.

[0048] When the spring-loaded piston 62 moves upward, it can make the tank 31 connected through the sleeve 61 and the exhaust pipe 63, and at this time the top of the hammer 64 can strike the bottom of the crucible 12.

[0049] Using the above scheme, during the metal smelting process, the gas continuously generated in the heat exchanger 2 is sent into the tank 31. When the pressure inside the tank 31 is too high, it will push the spring-loaded piston 62 upward and stretch the spring on it to store energy. When the spring-loaded piston 62 releases the blockage on the exhaust pipe 63, the gas inside the tank 31 will be discharged outward through the exhaust pipe 63 to ensure the stability of the pressure inside the tank 31. At the same time, during the upward movement, the spring-loaded piston 62 will also push the hammer end 64 upward and strike the bottom of the crucible 12 to make it vibrate, so as to ensure that the molten metal inside the crucible 12 is mixed evenly, and can also make the unmelted metal above the molten metal sink quickly in the liquid surface, thereby improving the smelting efficiency of the metal.

[0050] Working principle and usage process of this invention:

[0051] In use, the metal inside the crucible 12 is heated by a coil. The heat emitted from the crucible 12 heats the pure water in the heat exchange vertical tube 21 and the heat exchange ring tube 22. The emitted steam enters the tank 31 for storage through the ring tube 24, the air inlet pipe 32 and the one-way valve 33.

[0052] During the pouring of molten metal, the operator presses the spring combination core rod 43 to open the transverse cavity 44 to connect pipe 1 46 and pipe 2 47. The gas in the tank 31 enters the tension spring combination telescopic piston rod 41 through pipe 2 47, transverse cavity 44 and pipe 1 46, and drives the tension spring combination telescopic piston rod 41 to extend. The output end of the tension spring combination telescopic piston rod 41 pushes the outer shell 11 to drive the crucible 12 to rotate slowly around the axis on the support 111, thereby pouring out the molten metal in the crucible 12. After releasing the pressure on the spring combination core rod 43 so that it is reset by its own elastic force, pipe 1 46 is connected to the outside through the bending cavity 45. At this time, under the action of the tension spring combination telescopic piston rod 41, the outer shell 11 will be pulled to reset. At this time, the gas and residual liquid in the tension spring combination telescopic piston rod 41 will be discharged through pipe 1 46 and bending cavity 45.

[0053] During the metal smelting process, the gas continuously generated in the heat exchanger 2 is sent into the tank 31. When the pressure inside the tank 31 is too high, it will push the spring combination piston 62 upward and stretch the spring on it to store force. When the spring combination piston 62 releases the blockage of the exhaust pipe 63, the gas inside the tank 31 will be discharged outward through the exhaust pipe 63 to ensure the stability of the pressure inside the tank 31. At the same time, during the upward movement, the spring combination piston 62 will also push the hammer end 64 upward and hit the bottom of the crucible 12 to make it vibrate, so as to ensure that the molten metal inside the crucible 12 is evenly mixed and accelerate the discharge of gas in the molten metal. It can also make the unmelted metal above the molten metal sink quickly in the liquid surface.

[0054] When the device stops working, the gas temperature inside the heat insulation cover 13 will dissipate rapidly outward, causing the temperature inside the heat insulation cover 13, heat exchange vertical pipe 21 and heat exchange ring pipe 22 to drop rapidly. At this time, the liquid evaporated in the heat exchange vertical pipe 21 will condense and the pressure inside the heat exchange vertical pipe 21 will decrease and become negative pressure. At this time, the pure water in the water storage tank 51 will be unidirectionally transported to the heat exchange vertical pipe 21 through the one-way valve 53 and the tank body 52 for replenishment, and the pure water will be replenished to the other heat exchange vertical pipes 21 through the heat exchange ring pipe 22.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0056] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A precious metal smelting furnace with waste heat recovery function, comprising a smelting furnace (1), which includes a shell (11), a crucible (12) installed therein, and a heat insulation cover (13), wherein the crucible (12) is located in the heat insulation cover (13), and a bracket (111) is hinged to the shell (11), characterized in that, Also includes: A heat exchanger (2) containing pure water is installed inside a heat insulation cover (13). A pressure tank (3) connected to the top of the heat exchanger (2) is installed at the bottom of the outer shell (11). A drive mechanism (4) is installed at the top of the bracket (111). The drive mechanism (4) includes a tension spring combined telescopic piston rod (41) hinged to the top of the bracket (111), and the output end of the tension spring combined telescopic piston rod (41) is hinged to the outer shell (11). A sleeve (42) is fixedly connected to the top of the bracket (111). A spring combined core rod (43) is movably sleeved inside the sleeve (42). A pipe (46) and a pipe (47) are fixedly connected on the sleeve (42). The other ends of the pipe (46) and the pipe (47) are respectively connected to the tension spring combined telescopic piston rod (41) and the pressure tank (3). A transverse cavity (44) and a bending cavity (45) are opened on the spring combined core rod (43). Initially, the pipe (46) can be connected to the outside through the bending cavity (45). At this time, the pipe (47) is blocked by the outer periphery of the spring combined core rod (43). When the transverse cavity (44) moves downward, it can connect the pipe (46) and the pipe (47). A counterweight (112) is fixed to the bottom of the outer shell (11).

2. The precious metal smelting furnace with waste heat recovery function according to claim 1, characterized in that: The weight of the counterweight (112) is greater than the weight of the portion of the outer shell (11) located above the axis, and the tension spring combined telescopic piston rod (41) can be replaced by a piston telescopic rod.

3. The precious metal smelting furnace with waste heat recovery function according to claim 1, characterized in that: The diameter of the middle part of the transverse cavity (44) is smaller than the diameter of its two ends.

4. The precious metal smelting furnace with waste heat recovery function according to claim 1, characterized in that: The heat exchanger (2) includes several heat exchange vertical tubes (21), heat exchange ring tubes (22), annular fins (23) and a set of annular tubes (24). The heat exchange vertical tubes (21) are arranged in annular array on the outer periphery of the crucible (12) and the bottom end is installed at the bottom of the cavity of the heat insulation cover (13). Several heat exchange ring tubes (22) are arranged vertically at equal intervals on the heat exchange vertical tubes (21) and conduct the heat exchange vertical tubes (21). Several annular fins (23) are arranged vertically at equal intervals on the outer periphery of the heat exchange vertical tubes (21). The annular tubes (24) are located at the top of the heat exchange vertical tubes (21) to conduct the heat exchange vertical tubes (21). The heat exchange vertical tube (21) contains pure water, and the annular fin (23) at the top is above the pure water surface.

5. The precious metal smelting furnace with waste heat recovery function according to claim 4, characterized in that: The pressure tank (3) includes a tank body (31) fixed to the bottom of the cavity of the outer shell (11) and located below the heat insulation cover (13). The top of the tank body (31) is fixedly connected to an air inlet pipe (32). The top end of the air inlet pipe (32) extends into the heat insulation cover (13) and is connected to an annular pipe (24). A one-way valve (33) that can communicate with the tank body (31) in one direction is provided in the air inlet pipe (32). One end of the second pipe (47) can extend to the bottom of the cavity of the tank (31).

6. The precious metal smelting furnace with waste heat recovery function according to claim 4, characterized in that: The smelting furnace (1) is equipped with a water replenishment component (5) for replenishing pure water into the heat exchange vertical pipe (21).

7. The precious metal smelting furnace with waste heat recovery function according to claim 6, characterized in that: The water replenishment component (5) includes a water storage tank (51) fixedly installed between the bottom of the outer shell (11) and the counterweight (112). A box body (52) is fixedly connected to the water storage tank (51). The top of the box body (52) passes through the water storage tank (51), the outer shell (11) and the heat insulation cover (13) and can be fixedly connected to the annular pipe (24). A one-way valve (53) that can be unidirectionally connected to the annular pipe (24) is installed inside the box body (52). The top of the water storage tank (51) is also provided with a water inlet.

8. The precious metal smelting furnace with waste heat recovery function according to claim 7, characterized in that: The water inlet of the water storage tank (51) is provided with a one-way membrane flap (511), through which gas can enter the water storage tank (51) in one direction.

9. The precious metal smelting furnace with waste heat recovery function according to claim 5, characterized in that: The tank (31) is equipped with a pressure relief mechanism (6); The pressure relief mechanism (6) includes a sleeve two (61) fixedly attached to the tank body (31), and the top end of the sleeve two (61) passes through the tank body (31) and the heat insulation cover (13). An exhaust pipe (63) located outside the tank body (31) is fixedly connected to the sleeve two (61), and the other end of the sleeve two (61) can extend to the outside of the outer shell (11). A spring combination piston (62) that can initially block one end of the exhaust pipe (63) is movably connected inside the sleeve two (61). The top end of the spring combination piston (62) is fixedly attached to a hammer end (64) located at the bottom of the cavity of the heat insulation cover (13). When the spring-loaded piston (62) moves upward, it enables the tank (31) to be connected through the sleeve (61) and the exhaust pipe (63), and at this time the top of the hammer (64) can strike the bottom of the crucible (12).

Images