A high-temperature kiln waste heat recovery device coupled with molten salt heat extraction and storage and a process thereof

Abstract

This invention discloses a high-temperature kiln waste heat recovery device and its process coupled with molten salt heat extraction and storage. The device includes: a low-temperature tank capable of melting and transporting a circulating medium; a high-temperature tank capable of storing the molten circulating medium after heating and transporting the circulating medium; a first connecting pipe connecting the low-temperature tank and the high-temperature tank, used to transport the molten circulating medium from the low-temperature tank to the high-temperature tank, and the wall of the first connecting pipe is connected to a heat-conducting component inside the kiln; a heat exchange component capable of exchanging and releasing heat; and a second connecting pipe connecting the low-temperature tank and the high-temperature tank, used to transport the molten circulating medium from the high-temperature tank to the low-temperature tank, and the wall of the second connecting pipe is thermally connected to the heat exchange component. The process allows for controllable heat extraction at different kiln temperatures: high-temperature molten salt heat exchange is used when the kiln temperature is high, and low-temperature molten salt heat exchange is used when the kiln temperature is low, ensuring safe and stable heat extraction at different temperatures.

Description

Technical Field

[0001] This invention relates to the field of high-temperature furnace waste heat recovery and treatment, and particularly to a high-temperature kiln waste heat recovery device and its process that couples molten salt heat extraction and storage. Background Technology

[0002] In the production processes of high-temperature kilns such as graphitization furnaces, carbon furnaces, roasting furnaces, pre-carbonization kilns, ceramic kilns, and aluminum alloy melting furnaces, there is a high-temperature cooling process for finished products or waste residue. Most companies use methods such as direct blowing of cold air or water spraying for cooling, which wastes a lot of energy and affects the yield of finished products. At present, some companies in the industry have begun to conduct research on waste heat utilization technology for high-temperature kilns. Water is mostly used as the heat transfer medium, but most applications are limited to the stage of circulating heat exchange under fixed operating conditions, with relatively simple operation processes and a narrow range of system applicability. Summary of the Invention

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a high-temperature kiln waste heat recovery device coupled with molten salt heat extraction and storage, which can quickly recover waste heat and facilitate subsequent waste heat treatment.

[0004] A high-temperature kiln waste heat recovery process using the above-mentioned device for coupled molten salt heat extraction and storage is also proposed.

[0005] A high-temperature kiln waste heat recovery device with coupled molten salt heat extraction and storage according to a first aspect embodiment of the present invention includes:

[0006] Cryogenic tanks are capable of melting and transporting circulating media;

[0007] High-temperature tanks are capable of storing and transporting molten circulating media after heating.

[0008] A first connecting pipe connects the low-temperature tank and the high-temperature tank, and is used to transport molten circulating medium along the direction from the low-temperature tank to the high-temperature tank. The pipe wall of the first connecting pipe is used to connect with the interior of the kiln for heat conduction.

[0009] Heat exchange components are capable of exchanging and releasing heat;

[0010] The second connecting pipe connects the cryogenic tank and the high-temperature tank, and is used to transport molten circulating medium along the direction from the high-temperature tank to the cryogenic tank. The pipe wall of the second connecting pipe is used to conduct heat to the heat exchange assembly.

[0011] The high-temperature kiln waste heat recovery device with coupled molten salt heat extraction and storage according to the first aspect of the present invention has at least the following beneficial effects:

[0012] 1. The low-temperature tank transports molten circulating medium through the first connecting pipe. The first connecting pipe is thermally connected to the inside of the kiln and exchanges heat with the kiln. The temperature of the kiln will be higher than the temperature of the circulating medium in the first connecting pipe, causing the circulating medium in the first connecting pipe to heat up. However, the circulating medium is still in a molten state and will not vaporize. It enters the high-temperature tank in a heated molten state. At this time, the heat inside the kiln is transferred to the high-temperature tank, realizing the heat extraction from the inside of the kiln.

[0013] 2. The high-temperature tank can be transported through the second connecting pipe, which is thermally connected to the heat exchange component. The second connecting pipe will exchange heat with the heat exchange component, so that the molten circulating medium in the second connecting pipe will be cooled down to a certain extent after passing through the heat exchange component, but can still flow back to the low-temperature tank in a molten state. At this time, the heat in the high-temperature tank is transferred to the heat exchange component, realizing the release of heat inside the kiln.

[0014] 3. It can quickly collect heat inside the kiln and transfer it to the heat exchange components. The heat exchange components can then be used to centrally process the waste heat and rapidly cool the kiln, thus shortening the kiln's cooling time.

[0015] According to some embodiments of the present invention, the cryogenic tank is supplied with a molten circulating medium via a cryogenic molten salt pump.

[0016] According to some embodiments of the present invention, the high-temperature tank is supplied with a molten circulating medium via a high-temperature molten salt pump.

[0017] According to some embodiments of the present invention, the first connecting pipe passes through the interior of the kiln.

[0018] According to some embodiments of the present invention, the first connecting pipe is used to connect to the interior of the kiln via a heat-conducting element.

[0019] According to some embodiments of the present invention, the first connecting pipe is distributed in a serpentine or tortuous manner inside the kiln.

[0020] According to some embodiments of the present invention, the second connecting pipe passes through the heat exchange assembly.

[0021] According to some embodiments of the present invention, the second connecting pipe is provided with a plurality of heat dissipation fins at the connection point with the heat exchange assembly.

[0022] According to some embodiments of the present invention, the heat exchange assembly includes a heat exchange pipe and a heat exchange medium, the heat exchange medium being liquid or gaseous, the heat exchange medium flowing within the heat exchange pipe, and the heat exchange pipe being thermally connected to the second connecting pipe.

[0023] According to some embodiments of the present invention, the heat exchange assembly further includes a heat transfer medium, and the heat exchange pipe is thermally connected to the second connecting pipe through the heat transfer medium.

[0024] According to some embodiments of the present invention, the heat transfer medium is a solid, a liquid with a constrained form, or a gas with a constrained form.

[0025] According to some embodiments of the present invention, the cryogenic tank is provided with a first thermostat to heat and maintain the molten state of the circulating medium.

[0026] According to some embodiments of the present invention, the high-temperature tank has a second thermostat to heat and maintain the molten state of the circulating medium.

[0027] According to some embodiments of the present invention, both the first and second temperature-regulating elements are tank heat tracing devices.

[0028] According to some embodiments of the present invention, the cryogenic tank is provided with a melting chamber for replenishing the circulating medium. The melting chamber is capable of melting the solid circulating medium to a molten state and can be added to the cryogenic tank.

[0029] According to the second aspect of the present invention, the high-temperature kiln waste heat recovery process of coupled molten salt heat extraction and storage uses the high-temperature kiln waste heat recovery device of coupled molten salt heat extraction and storage described in the first aspect of the present invention.

[0030] The high-temperature kiln waste heat recovery process coupled with molten salt heat extraction and storage according to the second aspect of the present invention has at least the following beneficial effects: it can quickly process the waste heat during the heat dissipation of the high-temperature kiln, the kiln heats up faster, and the waste heat resource utilization efficiency is higher.

[0031] According to some embodiments of the present invention, multiple different and continuous temperature ranges are divided according to the kiln heat storage temperature range, and there is partial overlap between two adjacent temperature ranges. Each temperature range has a corresponding low temperature tank temperature.

[0032] When the kiln is in a heat dissipation state, the heat extraction state is regulated by the heat extraction system, the heat release state is regulated by the heat release system, and the heat storage state is regulated by the heat storage system.

[0033] The temperature range of the kiln is detected, and the temperature inside the low-temperature tank is adjusted to correspond to this temperature range through the heat extraction system, heat release system, and heat storage system.

[0034] Within the same temperature range, the temperature of the cryogenic tank is maintained by the heat extraction system, the heat release system, and the heat storage system. The temperature inside the cryogenic tank corresponds to this temperature range. The heat extraction system, the heat release system, and the heat storage system dissipate heat from the kiln until the temperature inside the kiln drops to the range where this temperature range overlaps with the next temperature range.

[0035] Entering the next temperature range, the temperature inside the low-temperature tank is adjusted to correspond to this temperature range through the heat extraction system, heat release system and heat storage system, and this temperature is maintained. The heat extraction system, heat release system and heat storage system continue to dissipate heat to the kiln.

[0036] Repeat the process within the temperature range until the kiln cools down to the lowest temperature range.

[0037] According to some embodiments of the present invention, the temperature T inside the kiln is detected. 炉 Detecting the temperature T inside the cryogenic tank 低 Detecting the temperature T inside the high-temperature tank 高 According to T 炉 T 低 T 高 The system calculates the ratio X of the system's heat load to the system's maximum heat release load. Each temperature range has a range of ratio values ​​for the system's heat load to the system's maximum heat release load. The system determines the temperature range of the kiln based on the range of ratio values ​​for X.

[0038] According to some embodiments of the present invention, the number of temperature ranges is three, namely a high temperature range, a medium temperature range, and a low temperature range;

[0039] If X is within the ratio range corresponding to the high temperature range, the flow rate input to the second connecting pipe is increased by adjusting the high temperature tank through the heat release system, and the heat exchange efficiency of the heat exchange components is adjusted to low efficiency through the heat storage system to increase the temperature inside the low temperature tank to correspond to the high temperature range.

[0040] If X is within the ratio range corresponding to the medium temperature range, the flow rate from the high temperature tank to the second connecting pipe is adjusted through the heat release system, the heat exchange efficiency of the heat exchange components is adjusted to the normal efficiency through the heat storage system, and the temperature inside the low temperature tank is reduced to correspond to the medium temperature range.

[0041] If X is within the ratio range corresponding to the low temperature range, the flow rate input to the second connecting pipe is reduced by adjusting the high temperature tank through the heat release system, and the heat exchange efficiency of the heat exchange components is adjusted to high efficiency through the heat storage system, thereby reducing the temperature inside the low temperature tank to correspond to the low temperature range.

[0042] According to some embodiments of the present invention, a temperature thermocouple is provided inside the kiln.

[0043] According to some embodiments of the present invention, a first flow meter, a first pressure gauge and a first temperature gauge are provided at the connection between the first connecting pipe and the low-temperature molten salt pump, and a first valve is provided at the portion of the first connecting pipe located between the low-temperature molten salt pump and the kiln; a second flow meter, a second pressure gauge and a second temperature gauge are provided after the first connecting pipe passes through the kiln, and a second valve is provided at the portion of the first connecting pipe located between the kiln and the high-temperature molten salt pump.

[0044] According to some embodiments of the present invention, a third flow meter, a third pressure gauge and a third temperature gauge are provided at the connection between the second connecting pipe and the high-temperature molten salt pump, and a third valve is provided in the portion of the second connecting pipe between the high-temperature molten salt pump and the heat exchange assembly; a fourth flow meter, a fourth pressure gauge and a fourth temperature gauge are provided after the second connecting pipe passes through the heat exchange assembly, and a fourth valve is provided in the portion of the second connecting pipe between the heat exchange assembly and the low-temperature molten salt pump.

[0045] According to some embodiments of the present invention, a heat exchange medium inlet valve is provided on the inlet side of the heat exchange pipeline.

[0046] According to some embodiments of the present invention, the temperature of the cryogenic tank corresponding to each temperature range is less than or equal to the minimum temperature of that temperature range.

[0047] According to some embodiments of the present invention, if the kiln is in a non-heat dissipation state, the low-temperature tank is kept in a heat preservation state through the heat extraction system; if the heat exchange component does not need to release heat, the high-temperature tank is kept in a heat preservation state through the heat release system.

[0048] According to some embodiments of the present invention, in the heat preservation state, both the low-temperature tank and the high-temperature tank maintain minimum output to ensure that the circulating medium in the first connecting pipe and the second connecting pipe remains in a molten state.

[0049] According to some embodiments of the present invention, in the heat extraction state, the low-temperature tank increases the flow rate input to the first connecting pipe to exceed the flow rate in its heat preservation state; in the heat release state, the high-temperature tank increases the flow rate input to the second connecting pipe to exceed the flow rate in its heat preservation state, and the heat exchange component starts to operate and exchange heat.

[0050] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0051] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0052] Figure 1 This is a schematic diagram of the structure of a high-temperature kiln waste heat recovery device with coupled molten salt heat extraction and storage according to an embodiment of the present invention.

[0053] Figure 2 for Figure 1 The dashed section is a flow diagram of the heat recovery system in the high-temperature kiln waste heat recovery process that couples molten salt heat extraction and storage.

[0054] Figure 3 for Figure 1The dashed section is a flow diagram of the heat release system in the high-temperature kiln waste heat recovery process that couples molten salt heat extraction and storage.

[0055] Figure 4 for Figure 1 The dashed section is a schematic diagram of the heat storage system in the high-temperature kiln waste heat recovery process involving coupled molten salt heat extraction and storage.

[0056] Icon labels:

[0057] Cryogenic tank 100; First thermostatic component 110; Melting chamber 120; Cryogenic molten salt pump 130;

[0058] High-temperature tank 200; Second thermostatic component 210; High-temperature molten salt pump 220;

[0059] First connecting pipe 300;

[0060] Heat exchanger assembly 400; heat exchange pipe 410; heat transfer medium 420;

[0061] Second connecting pipe 500;

[0062] Kiln 600. Detailed Implementation

[0063] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0064] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0065] In the description of this invention, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features or their sequential relationship.

[0066] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0067] It is understandable that the highest temperature of high-temperature kilns such as graphitization furnaces, carbon furnaces, calcining furnaces, pre-carbonization kilns, ceramic kilns, and aluminum alloy melting furnaces exceeds 600℃. During the material cooling process inside the kiln, the temperature difference between the front and back exceeds 400℃.

[0068] Reference Figure 1 As shown, a high-temperature kiln waste heat recovery device with coupled molten salt heat extraction and storage according to an embodiment of the present invention includes:

[0069] The cryogenic tank 100 is capable of melting and transporting circulating media;

[0070] The high-temperature tank 200 is capable of storing and transporting the molten circulating medium after heating.

[0071] The first connecting pipe 300 connects the low-temperature tank 100 and the high-temperature tank 200, and is used to transport molten circulating medium along the direction from the low-temperature tank 100 to the high-temperature tank 200. The pipe wall of the first connecting pipe 300 is used to connect with the interior of the kiln 600 for heat conduction.

[0072] The heat exchange component 400 is capable of exchanging and releasing heat.

[0073] The second connecting pipe 500 connects the low-temperature tank 100 and the high-temperature tank 200, and is used to transport molten circulating medium in the direction from the high-temperature tank 200 to the low-temperature tank 100. The pipe wall of the second connecting pipe 500 is used to conduct heat to the heat exchange component 400.

[0074] Specifically, the low-temperature tank 100 transports molten circulating medium through the first connecting pipe 300. The first connecting pipe 300 is thermally connected to the kiln 600, so the first connecting pipe 300 will exchange heat with the kiln 600. The temperature of the kiln 600 will be higher than the temperature of the circulating medium in the first connecting pipe 300, causing the circulating medium in the first connecting pipe 300 to heat up. However, the circulating medium is still in a molten state and will not vaporize. It enters the high-temperature tank 200 in a molten state after heating up. At this time, the heat inside the kiln 600 is transferred to the high-temperature tank 200, realizing the heat extraction from the inside of the kiln 600.

[0075] Furthermore, the high-temperature tank 200 can transport the heated and molten circulating medium through the second connecting pipe 500. The second connecting pipe 500 is thermally connected to the heat exchange component 400, so the second connecting pipe 500 will exchange heat with the heat exchange component 400. This causes the molten circulating medium in the second connecting pipe 500 to be cooled to a certain temperature after passing through the heat exchange component 400, but it can still flow back to the low-temperature tank 100 in a molten state. At this time, the heat in the high-temperature tank 200 is transferred to the heat exchange component 400, thus realizing the release of heat inside the kiln 600.

[0076] The above method enables the rapid collection of heat inside the kiln 600 and its transfer to the heat exchange component 400. The heat exchange component 400 then centrally processes the waste heat and rapidly cools the kiln 600, thus shortening its cooling time.

[0077] The circulating medium is molten salt. Users can select different molten salts according to the heat extraction requirements of different kilns 600. The temperature range of molten salt is 59℃~1400℃. Molten salt has a wide operating temperature range and can be matched with many types of kilns 600.

[0078] It is worth understanding that the cryogenic tank 100 can achieve the circulation of molten medium in the molten state through the cryogenic molten salt pump 130. The cryogenic molten salt pump 130 can be set inside the cryogenic tank 100 or outside the cryogenic tank 100, located between the cryogenic tank 100 and the first connecting pipe 300, and connected to both.

[0079] It is worth understanding that the high-temperature tank 200 can achieve the circulation of molten medium through the high-temperature molten salt pump 220. The high-temperature molten salt pump 220 can be set inside the high-temperature tank 200 or outside the high-temperature tank 200, located between the high-temperature tank 200 and the first connecting pipe 300, and connected to both.

[0080] The cryogenic tank 100 can transport molten circulating medium to the high-temperature tank 200 through the first connecting pipe 300 by controlling the cryogenic molten salt pump 130. The flow rate of the circulating medium in the first connecting pipe 300 can be controlled by controlling the cryogenic molten salt pump 130. The cryogenic molten salt pump 130 is a heat extraction system.

[0081] The high-temperature tank 200 can transport molten circulating medium to the low-temperature tank 100 through the high-temperature molten salt pump 220 along the second connecting pipe 500. The flow rate of the circulating medium in the second connecting pipe 500 can be controlled by controlling the high-temperature molten salt pump 220. The high-temperature molten salt pump 220 is a heat release system.

[0082] The heat extraction system and the heat release system exist independently and do not interfere with each other. They can operate simultaneously or be used separately.

[0083] In addition, the heat exchange component 400 can be connected to other waste heat utilization components to utilize waste heat, such as boilers, heating devices, etc.

[0084] Reference Figure 1 As shown, the first connecting pipe 300 passes through the interior of the kiln 600.

[0085] The phrase "the first connecting pipe 300 passes through the interior of the kiln 600" means that a portion of the first connecting pipe 300 is located inside the kiln 600.

[0086] It is worth noting that the first connecting pipe 300 is directly installed inside the kiln 600, directly exchanging heat with the heat inside the kiln 600. This causes the temperature of the molten circulating medium inside the first connecting pipe 300 to rise. Furthermore, since the first connecting pipe 300 directly exchanges heat with the inside of the kiln 600, the heat loss during the heat exchange process is smaller, and the waste heat utilization rate is higher.

[0087] In another implementation, the first connecting pipe 300 is used to connect to the interior of the kiln 600 via a heat-conducting element.

[0088] It is worth understanding that the first connecting pipe 300 can be set outside the kiln 600. Multiple heat conduction elements are set on the kiln 600. The heat conduction elements pass through the kiln 600 from inside the kiln 600 and extend outside the kiln 600 to conduct heat to the first connecting pipe 300.

[0089] It is worth understanding that the first connecting pipe 300 can also be connected to the heat conduction component inside the kiln 600.

[0090] Specifically, the heat transfer element can be a heat extraction pipe, a water-cooled wall, or other heat recovery device.

[0091] When the heat transfer element is a heat extraction pipe, the heat extraction pipe can be concentrically sleeved outside the first connecting pipe 300.

[0092] Reference Figure 1 As shown, the first connecting pipe 300 is distributed in a serpentine or tortuous manner inside the kiln 600.

[0093] It is understandable that by using a serpentine or tortuous shape, the length of the first connecting pipe 300 inside the kiln 600 is extended, increasing the contact area of ​​the first connecting pipe 300 inside the kiln 600, so that the first connecting pipe 300 can exchange more heat with the kiln 600, thereby improving the heat extraction efficiency of the first connecting pipe 300 inside the kiln 600.

[0094] Reference Figure 1 As shown, the second connecting pipe 500 passes through the heat exchange component 400.

[0095] Wherein, the second connecting pipe 500 passing through the heat exchange assembly 400 means that a portion of the second connecting pipe 500 is located within the heat exchange assembly 400.

[0096] It is worth understanding that the second connecting pipe 500 can be directly installed inside the heat exchange component 400, directly transferring the heat of the circulating medium to the heat exchange component 400, and releasing and processing the heat through the heat exchange component 400.

[0097] Reference Figure 1As shown, the second connecting pipe 500 is provided with multiple heat dissipation fins at the connection point with the heat exchange component 400.

[0098] It is understandable that by accelerating the heat exchange rate between the second connecting pipe 500 and the heat exchange component 400 through heat dissipation fins, the heat release efficiency of the circulating medium releasing heat into the heat exchange component 400 can be further improved.

[0099] Reference Figure 1 As shown, the heat exchange assembly 400 includes a heat exchange pipe 410 and a heat exchange medium, which is either liquid or gaseous. The heat exchange medium flows within the heat exchange pipe 410, and the heat exchange pipe 410 is thermally connected to the second connecting pipe 500.

[0100] It is worth understanding that the second connecting pipe 500 can be directly inserted into the heat exchange pipe 410 and then pass out from the heat exchange pipe 410, thereby connecting the heat exchange pipe 410 and the second connecting pipe 500. The second connecting pipe 500 will directly exchange heat with the heat exchange medium in the heat exchange pipe 410, resulting in higher heat exchange efficiency.

[0101] The heat exchange medium is either liquid or gaseous, which makes it fluid and facilitates the transfer of the heat exchange medium after heat exchange to utilize the heat.

[0102] In this embodiment, the heat exchange medium can be water, air, nitrogen, or carbon dioxide. Water, after heat exchange, can be converted into water vapor and transported in the heat exchange pipe 410.

[0103] Reference Figure 1 As shown, the heat exchange assembly 400 also includes a heat transfer medium 420, and the heat exchange pipe 410 is thermally connected to the second connecting pipe 500 through the heat transfer medium 420.

[0104] It is worth understanding that the second connecting pipe 500 can also be set outside the heat exchange pipe 410. The second connecting pipe 500 and the heat exchange pipe 410 are connected by a heat transfer medium 420. The heat exchange pipe 410 can absorb the heat in the second connecting pipe through the heat transfer medium 420 and transfer it to the heat exchange medium flowing in the heat exchange pipe 410. The second connecting pipe 500 and the heat exchange pipe 410 are easier to manufacture, the manufacturing process is mature, the device cost is low, and maintenance is convenient.

[0105] Reference Figure 1 As shown, the heat transfer medium 420 is a solid, a liquid with a constrained form, or a gas with a constrained form.

[0106] It is worth understanding that the heat transfer medium 420 can be a metal with high thermal conductivity, or a liquid or gas with high thermal conductivity that is confined by the chamber inside the box.

[0107] The enclosure itself can be made of heat-insulating material, which concentrates heat in the fluid heat transfer medium 420, reducing heat loss and improving waste heat utilization.

[0108] Reference Figure 1 As shown, the cryogenic tank 100 is equipped with a first thermostat 110 to heat and maintain the molten state of the circulating medium.

[0109] It is understandable that when the temperature inside the kiln 600 is low, such as during the loading or unloading process of the kiln 600, the circulating medium inside the low-temperature tank 100 is kept in a molten state by the first thermostatic element 110 and is transported to the first connecting pipe 300 by the low-temperature molten salt pump 130. This makes the molten circulating medium inside the low-temperature tank 100 and the first connecting pipe 300 less susceptible to solidification and can maintain its liquid fluidity, which is convenient for cooling when the kiln 600 dissipates heat.

[0110] Specifically, the first constant temperature component 110 is a heat tracing device for the storage tank. The structure and installation of the heat tracing device for the storage tank are common knowledge to those skilled in the art, and will not be described in detail here.

[0111] Reference Figure 1 As shown, the high-temperature tank 200 contains a second thermostat 210 to heat and maintain the molten state of the circulating medium.

[0112] It is understandable that when the temperature inside the kiln 600 is low, such as during the loading or unloading process of the kiln 600, the circulating medium inside the high-temperature tank 200 is kept in a molten state by the second thermostat 210 and transported to the second connecting pipe 500 by the high-temperature molten salt pump 220. This makes the molten circulating medium inside the high-temperature tank 200 and the second connecting pipe 500 less likely to be cooled and solidified, and can always maintain a liquid fluidity, which is convenient for cooling when the kiln 600 dissipates heat.

[0113] Specifically, the second constant temperature component 210 is a heat tracing device for the storage tank. The structure and installation of the heat tracing device for the storage tank are common knowledge to those skilled in the art, and will not be described in detail here.

[0114] Reference Figure 1 As shown, the cryogenic tank 100 is provided with a melting chamber 120 for replenishing the circulating medium. The melting chamber 120 can melt the solid circulating medium to a molten state and can be added into the cryogenic tank 100.

[0115] It is understandable that during the long-term use of the cryogenic tank 100 and the high-temperature tube, some circulating medium will be lost. The circulating medium, which is solid at room temperature, can be added to the melting chamber 120 and melted in the melting chamber 120. The solid circulating medium is then added to the cryogenic tank 100 to replenish the lost circulating medium and facilitate continuous long-term use.

[0116] Specifically, the melting chamber 120 is provided with a first replenishment port and a second replenishment port. The first replenishment port is connected to the outside, and solid circulating medium can be added into the melting chamber 120 through the first replenishment port. The second replenishment port is connected to the cryogenic tank 100. After the solid circulating medium in the melting chamber 120 is melted into a molten state, the molten circulating medium is added into the cryogenic tank 100 through the second replenishment port.

[0117] Among them, the melting chamber 120 is a salt dissolving device. The structure and installation of the salt dissolving device are common knowledge to those skilled in the art, and will not be described in detail here.

[0118] Reference Figures 1 to 4 As shown, the high-temperature kiln waste heat recovery process of coupled molten salt heat extraction and storage according to the second aspect of the present invention includes: a high-temperature kiln waste heat recovery device of coupled molten salt heat extraction and storage according to the first aspect of the present invention.

[0119] It is understandable that the waste heat recovery device for high-temperature kilns can quickly process the waste heat generated during the heat dissipation of the 600-degree high-temperature kiln, resulting in faster heat dissipation and higher efficiency in the utilization of waste heat resources.

[0120] In this embodiment, based on the heat storage temperature range of the kiln 600, multiple different and continuous temperature intervals are divided. There is some overlap between two adjacent temperature intervals. Each temperature interval has a corresponding temperature in a low-temperature tank 100.

[0121] When the kiln 600 is in a heat dissipation state, the heat extraction state is adjusted by the heat extraction system, the heat release state is adjusted by the heat release system, and the heat storage state is adjusted by the heat storage system.

[0122] The temperature range of the kiln 600 is detected, and the temperature inside the low-temperature tank 100 is adjusted to correspond to this temperature range through the heat extraction system, heat release system and heat storage system.

[0123] Within the same temperature range, the temperature of the low-temperature tank 100 is maintained by the heat extraction system, the heat release system and the heat storage system, and the temperature inside the low-temperature tank 100 corresponds to this temperature range. Heat is dissipated from the kiln 600 through the heat extraction system, the heat release system and the heat storage system until the temperature inside the kiln 600 drops to the range where this temperature range overlaps with the next temperature range.

[0124] Entering the next temperature range, the temperature inside the low-temperature tank 100 is adjusted to correspond to this temperature range through the heat extraction system, heat release system and heat storage system, and this temperature is maintained. The heat extraction system, heat release system and heat storage system continue to dissipate heat to the kiln 600.

[0125] Repeat the process within the temperature range until the kiln temperature drops to the lowest possible range.

[0126] The kiln 600 is equipped with a temperature thermocouple inside.

[0127] The connection between the first connecting pipe 300 and the low-temperature molten salt pump 130 is equipped with a first flow meter, a first pressure gauge and a first temperature gauge. The portion of the first connecting pipe 300 between the low-temperature molten salt pump 130 and the kiln 600 is equipped with a first valve. After the first connecting pipe 300 passes through the kiln 600, it is equipped with a second flow meter, a second pressure gauge and a second temperature gauge. The portion of the first connecting pipe 300 between the kiln 600 and the high-temperature molten salt pump 220 is equipped with a second valve.

[0128] The second connecting pipe 500 is equipped with a third flow meter, a third pressure gauge and a third temperature gauge at the connection between it and the high-temperature molten salt pump 220. The second connecting pipe 500 located between the high-temperature molten salt pump 220 and the heat exchange component 400 is equipped with a third valve. The second connecting pipe 500 is equipped with a fourth flow meter, a fourth pressure gauge and a fourth temperature gauge after passing through the heat exchange component 400. The second connecting pipe 500 located between the heat exchange component 400 and the low-temperature molten salt pump 130 is equipped with a fourth valve.

[0129] The heat exchange pipe 410 is equipped with a heat exchange medium inlet valve on the inlet side.

[0130] The heat extraction system controls the flow rate of the cryogenic molten salt pump 130 into the first connecting pipe 300 to transfer heat from the kiln 600 to the circulating medium. It also controls the heat extraction load by detecting the temperature T_low in the cryogenic tank 100 and the temperature T_furnace in the kiln 600 to maintain the molten salt temperature at the kiln 600 outlet and regulate the heat extraction status. When the kiln 600 is in a non-heat dissipation state, the heat extraction system is in a heat preservation state.

[0131] The heat release system controls the flow rate of the high-temperature molten salt pump 220 into the second connecting pipe 500. The high-temperature tank 200 stores some heat and controls the normal operation of the heat exchange assembly 400. Excess heat is released through the heat exchange assembly 400 to transfer the heat of the circulating medium to the heat exchange medium. At this time, the heat release system controls the high-temperature molten salt pump 220 by jointly controlling the heat release load of the heat exchange assembly 400 and the outlet temperature of the second connecting pipe 500 from the heat exchange assembly 400, thereby controlling the flow rate of the pump into the second connecting pipe 500. This maintains the system's heat release output while ensuring that the molten salt outlet temperature of the molten salt heat exchanger is above the design temperature, thus achieving regulation of the heat release state.

[0132] Furthermore, when there is no heat demand in the boiler or other equipment that utilizes the heat of the heat exchange component 400, that is, when the heat exchange component 400 does not need to release heat, the heat release system is in a heat preservation state, and the heat is stored in the high-temperature tank 200.

[0133] Among them, the heat storage system can monitor the temperature T inside the kiln at 600°C. 炉 Cryogenic tank, 100°C (T) 低 High-temperature tank, 200°C (T) 高 The overall temperature of the circulating medium can be adjusted by controlling the flow rate and velocity of the heat exchange medium in the heat exchange pipe 410. The flow rate and velocity can be controlled by the heat exchange medium inlet valve. The heat storage system adjusts the overall heat storage capacity of the circulating medium by controlling the heat exchange efficiency.

[0134] It is understandable that when the kiln 600 is preparing to dissipate heat, the residual heat inside the kiln 600 can be collected and the kiln 600 can be cooled down quickly. During the initial cooling, the kiln 600 will be in the highest temperature range. At this time, the heat extraction system extracts heat normally, the heat storage system controls the heat exchange component 400 to reduce the heat exchange efficiency, and the heat release system controls the high temperature molten salt pump 220 to increase the flow rate into the low temperature tank 100, so that the temperature in the low temperature tank 100 will be rapidly raised to the level corresponding to the highest temperature range.

[0135] When the temperature in the cryogenic tank 100 reaches the required temperature, the heat extraction system, heat release system, and heat storage system work together to maintain the temperature in the cryogenic tank 100, while the temperature in the kiln 600 gradually decreases until the temperature in the kiln 600 enters the overlap between the highest temperature range and the second highest temperature range. At this point, the kiln 600 enters the second highest temperature range. After entering the second highest temperature range, the heat extraction system, heat release system, and heat storage system work together to regulate the temperature in the cryogenic tank 100 so that the temperature in the cryogenic tank 100 corresponds to the second highest temperature range and maintain the temperature in the cryogenic tank 100, continuing to dissipate heat from the kiln 600.

[0136] When it is necessary to lower the temperature in the cryogenic tank 100, the heat exchange efficiency of the heat exchange component 400 can be increased or the circulating medium input from the high-temperature tank 200 to the second connecting pipe 500 can be reduced, so that the lower-temperature circulating medium enters the cryogenic tank 100 from the second connecting pipe 500, thereby achieving the cooling of the cryogenic tank 100.

[0137] It is understandable that when the kiln 600 first enters the heat dissipation state, it is at a high temperature, and the heat extraction load can exceed the heat release load by more than 10 times. If the heat extraction load needs to be stored, a very large high-temperature tank 200 and sufficient circulating medium are required for storage when the heat extraction load far exceeds the heat release load. However, by adjusting the temperature in the low-temperature tank 100 to correspond with the high-temperature range, the temperature difference between the low-temperature tank 100 and the kiln 600 is reduced, thereby reducing the heat extraction load. This allows each temperature range to correspond to an appropriate amount of heat extraction load to meet the release of the heat release load. Furthermore, the storage space required for the high-temperature tank 200 and the circulating medium is smaller, making installation, maintenance, and use more convenient.

[0138] Reference Figures 1 to 4 As shown, the temperature T inside the kiln at 600°C was measured. 炉 Detecting the temperature T inside the cryogenic tank 100 低 Temperature T inside the high-temperature tank 200 高 According to T 炉 T 低 T 高 The system calculates the ratio X of the system's heat load to the system's maximum heat release load. Each temperature range has a range of ratio values ​​for the system's heat load to the system's maximum heat release load. The system determines the temperature range of the kiln 600 based on the range of ratio values ​​for X.

[0139] The system heat load can be calculated using a formula, and its temperature T is related to the temperature of the circulating medium in the first connection channel of the cryogenic tank 100. 低 Flow rate and kiln internal temperature T 600 炉 High-temperature tank 200 internal temperature T 高 Related; the system's maximum heat release load is a pre-designed fixed value.

[0140] It is worth understanding that X is calculated by real-time temperature detection, and there are multiple corresponding ratio ranges for multiple pre-set temperature intervals. Some temperature intervals overlap, and some ratio ranges will also overlap. When the ratio ranges overlap, the overlapping part is counted as the ratio range with the smaller value.

[0141] Therefore, by comparing X with multiple ratio ranges to determine which ratio range it falls within, we can determine its temperature range.

[0142] Specifically, the thermal storage system determines the temperature range corresponding to the kiln 600 through X, and then controls the heat exchange component 400 and the high-temperature molten salt pump 220.

[0143] In this embodiment, there are three temperature ranges, namely a high temperature range, a medium temperature range, and a low temperature range.

[0144] If X is within the ratio range corresponding to the high temperature range, the flow rate input to the second connecting pipe 500 is increased by adjusting the high temperature tank 200 through the heat release system, and the heat exchange efficiency of the heat exchange component 400 is adjusted to low efficiency through the heat storage system to increase the temperature in the low temperature tank 100 to correspond to the high temperature range.

[0145] If X is within the ratio range corresponding to the medium temperature range, the flow rate from the high temperature tank 200 to the second connecting pipe 500 is adjusted normally through the heat release system, the heat exchange efficiency of the heat exchange component 400 is adjusted to normal efficiency through the heat storage system, and the temperature in the low temperature tank 100 is reduced to correspond to the medium temperature range.

[0146] If X is within the ratio range corresponding to the low temperature range, the flow rate input to the second connecting pipe 500 is reduced by adjusting the high temperature tank 200 through the heat release system, and the heat exchange efficiency of the heat exchange component 400 is adjusted to high efficiency through the heat storage system, thereby reducing the temperature inside the low temperature tank 100 to correspond to the low temperature range.

[0147] It is understandable that, within the ratio range corresponding to the high-temperature range, the flow rate in the second connecting pipe 500 is increased by the heat release system, allowing more high-temperature circulating medium to quickly enter the low-temperature tank 100 until the temperature inside the low-temperature tank 100 corresponds to the high-temperature range. Simultaneously, the heat exchange efficiency of the heat exchange component 400 is reduced to a low efficiency by the heat storage system, ensuring that the circulating medium in the second connecting pipe 500 does not exchange too much heat with the heat exchange component 400, and its temperature remains relatively high. After entering the low-temperature tank 100, this will raise the temperature of the low-temperature tank 100 until it corresponds to the high-temperature range. This rapid increase in the temperature inside the low-temperature tank 100 reduces the heat extraction load and decreases the heat storage pressure in the high-temperature tank 200.

[0148] After passing through the high-temperature zone, X falls within the ratio range corresponding to the medium-temperature zone. The flow rate from the high-temperature tank 200 to the second connecting pipe 500 is adjusted by the heat release system to slow down the entry of the higher-temperature circulating medium into the low-temperature tank 100. Under the same heat exchange efficiency, the temperature of the circulating medium decreases more, allowing it to enter the low-temperature tank 100 at a lower temperature, thus reducing the temperature inside the low-temperature tank 100 to correspond to the medium-temperature zone. Simultaneously, the heat exchange efficiency of the heat exchange component 400 is adjusted to normal efficiency by the heat storage system, causing excessive heat exchange between the circulating medium in the second connecting pipe 500 and the heat exchange component 400, thereby reducing the temperature of the circulating medium until the temperature inside the low-temperature tank 100 corresponds to the medium-temperature zone. This achieves a rapid reduction in the temperature inside the low-temperature tank 100, stabilizing the temperature difference between the low-temperature tank 100 and the kiln 600 to maintain the heat extraction load.

[0149] After passing through the intermediate temperature range, X falls within the ratio range corresponding to the low temperature range. The heat release system adjusts the flow rate of the high-temperature tank 200 into the second connecting pipe 500, further slowing down the entry of the intermediate temperature circulating medium into the low-temperature tank 100. Under the same heat exchange efficiency, the temperature of the circulating medium decreases more, allowing it to enter the low-temperature tank 100 at a lower temperature, thus reducing the temperature inside the low-temperature tank 100 to correspond to the low-temperature range. Simultaneously, the heat storage system adjusts the heat exchange efficiency of the heat exchange component 400 to a higher efficiency, causing excessive heat exchange between the circulating medium in the second connecting pipe 500 and the heat exchange component 400, thereby reducing the temperature of the circulating medium until the temperature inside the low-temperature tank 100 corresponds to the low-temperature range. This achieves a rapid reduction in the temperature inside the low-temperature tank 100, stabilizing the temperature difference between the low-temperature tank 100 and the kiln 600 to maintain the heat extraction load.

[0150] In this embodiment, the ratio range corresponding to the high temperature range is greater than or equal to 1.2, the ratio range corresponding to the medium temperature range is 0.5 to 1.2, and the ratio range corresponding to the low temperature range is 0 to 0.5.

[0151] In this embodiment, the temperature of the cryogenic tank 100 corresponding to each temperature range is less than or equal to the minimum temperature of that temperature range.

[0152] It is worth understanding that when the temperature ranges are arranged from high to low, adjacent temperature ranges are respectively a higher temperature range and a lower temperature range. The lowest temperature of the higher temperature range is located within the lower temperature range and coincides with the highest temperature of the lower temperature range. When the temperature in the higher temperature range drops to the lowest temperature, the kiln 600 will move from the higher temperature range to the lower temperature range, and the temperature of the low-temperature tank 100 will also change, further decreasing, so that a stable temperature difference is maintained between the low-temperature tank 100 and the kiln 600 to maintain the size of the heat load.

[0153] Furthermore, when the temperature inside the kiln 600 reaches the highest temperature of the lower temperature range, the temperature range corresponding to the kiln 600 will change from the higher temperature range to the lower temperature range, and the temperature corresponding to the low-temperature tank 100 will become the lowest temperature of the lower temperature range. The temperature difference between the low-temperature tank 100 and the kiln 600 will further increase to continuously and effectively maintain the heat extraction load for heat extraction. This process continues until the kiln 600 dissipates heat to the lowest temperature range, which can be determined according to the cooling temperature required by the kiln 600 during the design phase.

[0154] In this embodiment, if the kiln 600 is in a non-heat dissipation state, the low-temperature tank 100 is in a heat preservation state through the heat extraction system; if the heat exchange component 400 does not need to release heat, the high-temperature tank 200 is in a heat preservation state through the heat release system.

[0155] In this embodiment, under heat preservation conditions, both the low-temperature tank 100 and the high-temperature tank 200 maintain minimum output to ensure that the circulating medium in the first connecting pipe 300 and the second connecting pipe 500 remains in a molten state.

[0156] Specifically, during the charging or discharging process of the kiln 600, the kiln 600 is in a non-heat-dissipating state, and the temperature inside the kiln 600 is close to room temperature. At room temperature, the molten salt exists in a solid state. In order to prevent the molten salt in the molten state from solidifying in the low-temperature tank 100 and the first connecting pipe 300, and at the same time to save energy, the low-temperature tank 100 is kept heated, and the molten circulating medium is input into the first connecting pipe 300 through the low-temperature molten salt pump 130.

[0157] When the heat exchange component 400 does not need to release heat, the high-temperature tank 200 is kept heated, and the molten circulating medium is introduced into the second connecting pipe 500 through the high-temperature molten salt pump 220 to avoid the temperature of the molten salt in the high-temperature tank 200 and the second connecting pipe 500 dropping too quickly, which is not conducive to the recovery and utilization of heat.

[0158] In addition, in the heat extraction state, the low-temperature tank 100 increases the flow rate input to the first connecting pipe 300 to exceed the flow rate in its heat preservation state; in the heat release state, the high-temperature tank 200 increases the flow rate input to the second connecting pipe 500 to exceed the flow rate in its heat preservation state, and the heat exchange component 400 starts to work and exchange heat.

[0159] The following example illustrates the graphitization furnace coupled with molten salt for heat extraction and storage. It should be understood that the following content does not constitute a specific limitation on the present invention.

[0160] During the initial cooling stage of the graphitization furnace, the temperature of the insulation layer inside the furnace is 1100℃, and the discharge temperature is 400℃.

[0161] Carbonates were selected as the molten salt for this system. The applicable temperature range of the molten salt is 317℃~800℃. The temperature range for this molten salt system design is 330~700℃. The low temperature operating range is defined as 330~500℃, the medium temperature operating range as 400~600℃, and the high temperature operating range as 500~700℃.

[0162] The external heat transfer system uses water as the medium, with an inlet temperature of 40°C and an outlet temperature of saturated steam.

[0163] 1. During the high-temperature heat storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a high-temperature heat storage status judgment signal. The heat extraction system, heat storage system, and heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 500℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 700℃ by the low-temperature molten salt pump. That is, the system's operating temperature range is 500~700℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0164] 2. During the intermediate-temperature thermal storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a signal to determine the intermediate-temperature thermal storage status. The heat extraction system, the heat storage system, and the heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 400℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 600℃ by the low-temperature molten salt pump. That is, the system's operating temperature range is 400~600℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0165] 3. During the low-temperature heat storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a low-temperature heat storage status judgment signal. The heat extraction system, heat storage system, and heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 330℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 500℃ by the low-temperature molten salt pump. That is, the system's operating temperature range is 330~500℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0166] The following description uses a roasting furnace with coupled molten salt heat extraction and storage as an example. It should be understood that the following content does not constitute a specific limitation on the present invention.

[0167] The initial temperature of the roasting furnace during the cooling stage is 800℃, and the discharge temperature is 300℃.

[0168] Nitrate was selected as the molten salt for this system. The applicable temperature range of the molten salt is 160℃~540℃. The temperature range for this molten salt system design is 170~500℃. The low temperature operating range is defined as 170~300℃, the medium temperature operating range as 250~400℃, and the high temperature operating range as 350~500℃.

[0169] The external heat transfer system uses water as the medium, with an inlet temperature of 40°C and an outlet temperature of saturated steam.

[0170] 1. During the high-temperature heat storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a high-temperature heat storage status judgment signal. The heat extraction system, heat storage system, and heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 350℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 500℃ by the low-temperature molten salt pump. That is, the system's operating temperature range is 350~500℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0171] 2. During the intermediate-temperature thermal storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a signal to determine the intermediate-temperature thermal storage status. The heat extraction system, the heat storage system, and the heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 250°C. The temperature of the molten salt at the graphitization furnace outlet is controlled at 400°C by the low-temperature molten salt pump. That is, the system's operating temperature range is 250 to 400°C. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0172] 3. During the low-temperature heat storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a low-temperature heat storage status judgment signal. The heat extraction system, heat storage system, and heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 170℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 300℃ by the low-temperature molten salt pump. That is, the system operating temperature range is 170~300℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0173] The following example illustrates the heat recovery of slag from a thermal power plant using coupled molten salt heat extraction and storage. It should be understood that the following content does not constitute a specific limitation on the present invention.

[0174] The slag cooling temperature of thermal power plants is 600℃, and the discharge temperature is below 200℃.

[0175] Nano-modified fused salt was selected as the fused salt for this system. The applicable temperature range of the fused salt is 120℃~440℃. The temperature range for this fused salt system design is 150~400℃. The low temperature operating range is defined as 150~200℃, the medium temperature operating range as 200~300℃, and the high temperature operating range as 300~400℃.

[0176] The external heat transfer system uses water as the medium, with an inlet temperature of 40°C and an outlet temperature of saturated steam.

[0177] 1. During the high-temperature heat storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a high-temperature heat storage status judgment signal. The heat extraction system, heat storage system, and heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 300℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 400℃ by the low-temperature molten salt pump. That is, the system's operating temperature range is 300~400℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0178] 2. During the intermediate-temperature thermal storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a signal to determine the intermediate-temperature thermal storage status. The heat extraction system, the heat storage system, and the heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 200℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 300℃ by the low-temperature molten salt pump. That is, the system's operating temperature range is 200~300℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0179] 3. During the low-temperature heat storage stage, the system receives the temperature signal inside the furnace, compares and calculates it, and then gives a low-temperature heat storage status judgment signal. The heat extraction system, heat storage system, and heat release system work together to adjust the temperature of the low-temperature molten salt storage tank to around 150℃. The temperature of the molten salt at the graphitization furnace outlet is controlled at 200℃ by the low-temperature molten salt pump. That is, the system operating temperature range is 150~200℃. Part of the extracted heat is stored in the high-temperature molten salt storage tank, and part is released through the molten salt heat exchanger.

[0180] 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 to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A high-temperature kiln waste heat recovery process coupled with molten salt heat extraction and storage, characterized in that, include: Cryogenic tank (100) is capable of melting and transporting circulating media; The high-temperature tank (200) is capable of storing the circulating medium that has been heated to molten, and is also capable of transporting the circulating medium. The first connecting pipe (300) connects the low-temperature tank (100) and the high-temperature tank (200) and is used to transport molten circulating medium in the direction from the low-temperature tank (100) to the high-temperature tank (200), and the pipe wall of the first connecting pipe (300) is used to conduct heat to the inside of the kiln (600). The heat exchange component (400) is capable of exchanging and releasing heat; The second connecting pipe (500) connects the low-temperature tank (100) and the high-temperature tank (200) and is used to transport molten circulating medium in the direction from the high-temperature tank (200) to the low-temperature tank (100). The pipe wall of the second connecting pipe (500) is used to conduct heat to the heat exchange assembly (400). Based on the heat storage temperature range of the kiln (600), multiple different and continuous temperature ranges are divided. There is some overlap between two adjacent temperature ranges. Each temperature range has a corresponding temperature in a low-temperature tank (100). When the kiln (600) is in a heat dissipation state, the heat extraction state is adjusted by the heat extraction system, the heat release state is adjusted by the heat release system, and the heat storage state is adjusted by the heat storage system. The temperature range of the kiln (600) is detected, and the temperature inside the low-temperature tank (100) is adjusted to correspond to this temperature range through the heat extraction system, heat release system and heat storage system; Within the same temperature range, the temperature of the low-temperature tank (100) is maintained by the heat extraction system, the heat release system and the heat storage system, and the temperature inside the low-temperature tank (100) corresponds to this temperature range. Heat is dissipated from the kiln (600) through the heat extraction system, the heat release system and the heat storage system until the temperature inside the kiln (600) drops to the range where this temperature range coincides with the next temperature range. Entering the next temperature range, the temperature inside the low-temperature tank (100) is adjusted to correspond to this temperature range through the heat extraction system, heat release system and heat storage system, and this temperature is maintained. The heat extraction system, heat release system and heat storage system continue to dissipate heat to the kiln (600). Repeat the process for each temperature range until the kiln (600) cools down to the lowest temperature range.

2. The high-temperature kiln waste heat recovery process coupled with molten salt heat extraction and storage according to claim 1, characterized in that: The heat exchange assembly (400) includes a heat exchange pipe (410) and a heat exchange medium, which is liquid or gaseous. The heat exchange medium flows within the heat exchange pipe (410), and the heat exchange pipe (410) is thermally connected to the second connecting pipe (500).

3. The high-temperature kiln waste heat recovery process coupled with molten salt heat extraction and storage according to claim 1, characterized in that: The first connecting pipe (300) is used to conduct heat to the inside of the kiln (600) through a heat conduction element.

4. The high-temperature kiln waste heat recovery process with coupled molten salt heat extraction and storage according to any one of claims 1 to 3, characterized in that: The cryogenic tank (100) is equipped with a first thermostat (110) to heat and maintain the molten state of the circulating medium.

5. The high-temperature kiln waste heat recovery process with coupled molten salt heat extraction and storage according to any one of claims 1 to 3, characterized in that: The cryogenic tank (100) is provided with a melting chamber (120) for replenishing the circulating medium. The melting chamber (120) can melt the solid circulating medium to a molten state and can be added to the cryogenic tank (100).

6. The high-temperature kiln waste heat recovery process with coupled molten salt heat extraction and storage according to claim 1, characterized in that: detecting the temperature T in the kiln (600) 炉 detecting the temperature T in the low-temperature tank (100) 低 detecting the temperature T in the high-temperature tank (200) 高 calculating the ratio X of the system heat extraction load and the system maximum heat release load according to T 炉 , T 低 , T 高 Each temperature interval has a ratio range of the system heat extraction load and the system maximum heat release load. The system determines the temperature interval of the kiln (600) according to the ratio range where X is located.

7. The high-temperature kiln waste heat recovery process coupled with molten salt heat extraction and storage according to claim 6, characterized in that: There are three temperature ranges: high temperature range, medium temperature range, and low temperature range. If X is within the ratio range corresponding to the high temperature range, the flow rate input to the second connecting pipe (500) is increased by adjusting the high temperature tank (200) through the heat release system, and the heat exchange efficiency of the heat exchange component (400) is adjusted to low efficiency by adjusting the heat storage system, thereby increasing the temperature in the low temperature tank (100) to correspond to the high temperature range. If X is within the ratio range corresponding to the medium temperature range, the flow rate of the high temperature tank (200) to the second connecting pipe (500) is adjusted normally through the heat release system, the heat exchange efficiency of the heat exchange component (400) is adjusted to the normal efficiency through the heat storage system, and the temperature in the low temperature tank (100) is reduced to the level corresponding to the medium temperature range. If X is within the ratio range corresponding to the low temperature range, the flow rate input to the second connecting pipe (500) is reduced by adjusting the high temperature tank (200) through the heat release system, and the heat exchange efficiency of the heat exchange component (400) is adjusted to high efficiency through the heat storage system, thereby reducing the temperature inside the low temperature tank (100) to correspond to the low temperature range.

8. The high-temperature kiln waste heat recovery process using molten salt heat extraction and storage according to any one of claims 6 to 7, characterized in that: The temperature of the cryogenic tank corresponding to each temperature range is less than or equal to the minimum temperature of that temperature range.

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