CN112857068B

CN112857068B - Heat recovery crucible cooling system for electric arc furnace steelmaking and application method thereof

Info

Publication number: CN112857068B
Application number: CN202110070757.8A
Authority: CN
Inventors: 杨凌志; 陈凤; 郑富强; 郭宇峰; 胡航; 王帅; 李勃; 姜涛; 李光辉; 李骞; 景建发; 薛波涛
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2021-01-19
Filing date: 2021-01-19
Publication date: 2022-01-11
Anticipated expiration: 2041-01-19
Also published as: CN112857068A

Abstract

The invention discloses a heat recovery crucible cooling system for electric arc furnace steelmaking and an application method thereof, wherein the heat recovery crucible cooling system for electric arc furnace steelmaking comprises: the flue gas heat exchange device is connected with a flue and a dust collecting hood of the electric arc furnace so as to recover heat in the high-temperature flue gas; the high-temperature side of the semiconductor temperature difference power generation device is connected with the flue gas heat exchange device so as to utilize the heat recovered by the flue gas heat exchange device to carry out temperature difference power generation; the semiconductor temperature difference power generation device is connected with the crucible cooling device and supplies power to the crucible cooling device. The heat recovery crucible cooling system for the electric arc furnace steelmaking solves a series of problems that the flue gas heat loss is serious, the temperature of the crucible is too high, the crucible is not easy to take out, the smelting process is influenced and the like in the smelting process of a laboratory semi-industrial electric arc furnace.

Description

Heat recovery crucible cooling system for electric arc furnace steelmaking and application method thereof

Technical Field

The invention relates to the technical field of electric arc furnace steelmaking, in particular to a heat recovery and crucible cooling system for steelmaking of a laboratory semi-industrial direct current electric arc furnace and an application method thereof.

Background

Compared with the long process of producing steel by sintering machines, blast furnaces and converters, the short-process steelmaking method taking electric arc furnace steelmaking as the core has the characteristics of energy conservation, environmental protection, high efficiency, good product applicability and the like. With the gradual attention of the country to energy conservation and environmental protection in the industrial field and the gradual policy inclination of process consumption reduction, the steel production industry of households with large energy consumption needs to pay attention to how to further save energy in the future, and the electric arc furnace steel making can be further developed. Meanwhile, the electric arc furnace has wide application in the aspects of treating dangerous waste such as municipal refuse incineration fly ash, bottom slag and the like and extracting minerals, and can adapt to various complex raw material conditions and smelting requirements.

With the development of electric arc furnace steelmaking equipment and the progress of smelting technology, nowadays, many domestic steel mills prefer to select an ultrahigh power electric arc furnace rather than a common electric arc furnace. The ultrahigh power electric arc furnace has obvious advantages in integrated control and process consumption reduction, and certainly needs a corresponding large furnace volume, so that more steel furnace materials can be processed. However, there are problems associated with the many studies carried out on electric arc furnaces.

The electric arc furnace steelmaking process is continuously carried out, strict requirements are imposed on the smelting shutdown time, simultaneously, the furnace charging materials are large, the electric arc furnace steelmaking process is not suitable for being used as smelting test equipment, generally, smelting operation with mature process and technology is carried out, however, a plurality of research works mainly about the electric arc furnace process, such as hazardous waste treatment, electric furnace melting and the like, are mostly in a test stage, the process and related technologies are not mature enough, the limit is caused by cost, smelting conditions and the like, and large-scale industrial experiments cannot be carried out to verify the theoretical analysis and research results. Therefore, in addition to numerical simulation, laboratory bench scale arc furnace equipment testing is the best option.

The laboratory is with electric arc furnace capacity less, generally adopts graphite crucible splendid attire material, and the charge is generally 6 ~ 15kg, relies on single graphite electrode and furnace charge to release heat and melts the furnace charge, carries out relevant smelting operation according to actual technological requirement, obtains result and scheme that have practical value, and equipment input cost is lower with the smelting cost moreover, and the experimental result has the reliability, has become the indispensable link of a great deal of smelting technology before the industrial practice at present.

In the actual smelting process of a semi-industrial electric arc furnace (shown in figure 1) for a laboratory, a crucible is fixed in a hearth of the electric arc furnace, asbestos is filled in a gap between the outer wall surface of the crucible and the hearth, the crucible is fixed and a certain heat preservation effect is achieved, heat loss is delayed, and continuous high temperature in the smelting process is guaranteed. The temperature of the electric arc generated by the electrode is high, and the furnace burden can be heated to 1400-1750 ℃ after being melted, so that the requirements of relevant smelting operation and process are met. After smelting, the crucible temperature is higher, can not take out at once and carry out the smelting operation of next stove, and conventional processing mode is to wait for crucible natural cooling, then takes out the crucible, carries out the analysis detection work of material in the subsequent crucible, nevertheless waits for its natural cooling, needs consuming time 15 ~ 20h, and the temperature of crucible outer wall could descend to can take out and can not scald the temperature. The defect influences the normal crucible smelting process in a laboratory, wastes the experimental time, and can cause adverse damage such as oxidation to some crystal phases formed by materials in a high-temperature environment, thereby influencing the experimental effect.

It needs to be noted simultaneously that, because of the needs that artifical reinforced and experimental phenomenon observed in the experimentation, general crucible upper portion does not seal with the lid, will lead to having a large amount of high temperature flue gas directly to upwards spill over like this, takes away a large amount of used heat, causes adverse effect to the subsequent dust removal sack of electric arc furnace flue, and the electric arc furnace body also can absorb a large amount of heats simultaneously, and the temperature is higher, causes bigger hindrance with further analysis to taking out of follow-up crucible. In addition, parts such as a transformer in the smelting process generate heat seriously, so that the risk of burning loss exists, excessive local heat is concentrated to be very unfavorable for the smelting process, and local waste heat is difficult to be directly utilized in the smelting process, so that extra energy loss and waste are caused. Therefore, the waste heat recovery and utilization of this portion must be regarded and dealt with.

Disclosure of Invention

The invention mainly aims to provide a heat recovery crucible cooling system for electric arc furnace steelmaking and an application method thereof, and at least solves the problems that the electric arc furnace has serious heat loss of flue gas, the crucible has overhigh temperature and is not easy to take out, the smelting time is long, and the product materials are easy to oxidize in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a heat recovery crucible cooling system for electric arc furnace steelmaking, comprising:

the flue gas heat exchange device is connected with a flue and a dust collecting hood of the electric arc furnace so as to recover heat in the high-temperature flue gas;

the high-temperature side of the semiconductor temperature difference power generation device is connected with the flue gas heat exchange device so as to utilize the heat recovered by the flue gas heat exchange device to carry out temperature difference power generation;

the semiconductor temperature difference power generation device is connected with the crucible cooling device and supplies power to the crucible cooling device.

Further, the flue gas heat exchange device comprises:

the other end of the high-temperature heat pipe of the flue gas side heat conduction oil pool is connected with the high-temperature side of the semiconductor temperature difference power generation device;

the smoke heat exchange tube is arranged in the flue and the dust collection cover, a smoke heat exchange tube heat conduction oil inlet is formed in the upper end of the flue of the smoke heat exchange tube, and a smoke heat exchange tube heat conduction oil outlet is formed in the lower end of the smoke heat exchange tube in the dust collection cover;

a flue gas side heat conduction oil pool heat conduction oil outlet pipeline, wherein one end of the flue gas side heat conduction oil pool heat conduction oil outlet pipeline is connected with the flue gas side heat conduction oil pool, the other end of the flue gas side heat conduction oil pool heat conduction oil outlet pipeline is connected with a flue gas heat exchange tube heat conduction oil inlet, and a flue gas side heat conduction oil pump is arranged on the flue gas side heat conduction oil pool heat conduction oil outlet pipeline;

the heat transfer oil inlet pipeline of the smoke side heat transfer oil pool is connected with the smoke side heat transfer oil pool at one end, and the heat transfer oil inlet pipeline of the smoke side heat transfer oil pool at the other end is connected with the smoke heat transfer oil outlet of the smoke heat exchange pipe.

Further, the flue gas heat exchange tube comprises:

the inner flue gas heat exchange pipe is filled with a phase change heat absorption material;

the flue gas heat exchange outer pipe is sleeved outside the flue gas heat exchange inner pipe, flue gas side hot oil guide channels for heat conduction oil to flow through are formed between the flue gas heat exchange outer pipe and the flue gas heat exchange inner pipe at intervals, one end of the flue gas heat exchange outer pipe is connected with the flue gas side hot oil guide outlet pipeline, and the other end of the flue gas heat exchange outer pipe is connected with the flue gas side hot oil guide outlet pipeline;

the high-temperature heat pipe of the flue gas side interlayer is arranged in the hot oil guide channel of the flue gas side, extends out of the flue gas heat exchange outer pipe and is connected with the high-temperature side of the semiconductor temperature difference power generation device.

Further, the smoke side heat conduction oil pool is also connected with a smoke side heat conduction oil pool metal Seebeck effect temperature measurement pipe, and the other end of the smoke side heat conduction oil pool metal Seebeck effect temperature measurement pipe is connected with the high-temperature side of the semiconductor temperature difference power generation device.

Furthermore, a smoke metal Seebeck effect temperature measuring tube is arranged in the dust hood, and the other end of the smoke metal Seebeck effect temperature measuring tube is connected with the high-temperature side of the semiconductor temperature difference power generation device.

Furthermore, a flue gas heat exchange tube heat conduction oil inlet and a flue gas heat exchange tube heat conduction oil outlet of the flue gas heat exchange tube are detachably connected with a flue gas side heat conduction oil pool heat conduction oil outlet pipeline and a flue gas side heat conduction oil pool heat conduction oil inlet pipeline respectively through a three-way pipe.

Further, the crucible cooling device includes:

the air cooling fan is connected with the semiconductor temperature difference power generation device and can be rotatably arranged on a hearth of the electric arc furnace through a rotating mechanism.

Further, the crucible cooling device further comprises:

the crucible water cooling device comprises a closed circulation water tank and a crucible water cooling spiral pipe, wherein the closed circulation water tank is respectively connected with two ends of the crucible water cooling spiral pipe through a crucible water cooling water supply pipe and a crucible water cooling return pipe, the crucible water cooling spiral pipe is sleeved on a crucible of the electric arc furnace, and a crucible water cooling water supply pump is arranged on the crucible water cooling water supply pipe.

Further, still include a transformer heat transfer device, transformer heat transfer device includes:

the transformer side heat conduction oil pool is connected with a transformer side heat conduction oil pool high-temperature heat pipe, and the other end of the transformer side heat conduction oil pool high-temperature heat pipe is connected with the high-temperature side of the semiconductor temperature difference power generation device;

the transformer side spiral heat exchange tube is arranged in a transformer rectifier cover of the electric arc furnace so as to recover the heat of the transformer;

the transformer side heat conduction oil return pipeline is characterized by comprising a transformer side heat conduction oil return pipeline, wherein one end of the transformer side heat conduction oil return pipeline is connected with a transformer side heat conduction oil pool, the other end of the transformer side heat conduction oil return pipeline is connected with an oil outlet of a transformer side spiral heat exchange tube, and a transformer side heat conduction oil pump and a multipoint balance heat exchange water cooling protector are arranged on the transformer side heat conduction oil return pipeline;

one end of the transformer side hot oil conducting and discharging pipeline is connected with the transformer side hot oil conducting pool, and the other end of the transformer side hot oil conducting and discharging pipeline is connected with an oil inlet of the transformer side spiral heat exchange tube;

furthermore, the transformer heat exchange device also comprises a transformer side heat conduction oil pool metal Seebeck effect temperature measurement tube, one end of the transformer side heat conduction oil pool metal Seebeck effect temperature measurement tube extends into the transformer side heat conduction oil pool, and the other end of the transformer side heat conduction oil pool metal Seebeck effect temperature measurement tube is connected with the high-temperature side of the semiconductor temperature difference power generation device.

Further, the transformer side spiral heat exchange tube comprises:

the transformer side heat exchange inner tube is filled with a phase change heat absorption material;

the transformer side heat exchange outer pipe is sleeved outside the transformer side heat exchange inner pipe, transformer side heat exchange outer pipes and the transformer side heat exchange inner pipe form transformer side heat conduction oil channels for heat conduction oil to flow through at intervals, one end of each transformer side heat exchange outer pipe is connected with a transformer side heat conduction oil return pipeline, and the other end of each transformer side heat exchange outer pipe is connected with a transformer side heat conduction oil return pipeline.

Further, the transformer heat exchange device comprises a plurality of transformer side spiral heat exchange tubes which are connected in series in a detachable mode.

Furthermore, the semiconductor thermoelectric power generation device comprises high-temperature side heat conduction ceramic, a high-temperature side metal plate, an N-type semiconductor, a P-type semiconductor, a low-temperature side metal plate, a low-temperature side heat conduction ceramic and an energy storage power supply, wherein the high-temperature side heat conduction ceramic is the high-temperature side of the semiconductor thermoelectric power generation device, the high-temperature side heat conduction ceramic is connected with the high-temperature side metal plate, the N-type semiconductor and the P-type semiconductor are both connected with the high-temperature side metal plate, the other ends of the N-type semiconductor and the P-type semiconductor are respectively connected with one low-temperature side metal plate, the two low-temperature side metal plates are connected with one low-temperature side heat conduction ceramic, and the two low-temperature side metal plates are respectively connected with the energy storage power supply through one lead.

Furthermore, a semiconductor thermoelectric generation unit is formed by a high-temperature side metal plate, an N-type semiconductor, a P-type semiconductor and two low-temperature side metal plates together, the semiconductor thermoelectric generation device comprises a plurality of semiconductor thermoelectric generation units, and the semiconductor thermoelectric generation units are connected in series.

According to another aspect of the present invention, there is provided a method for using the heat recovery crucible cooling system for steelmaking in an electric arc furnace, comprising:

at the beginning stage of smelting of the electric arc furnace, the input power of the electrode is low, sensible heat contained in the flue gas is low, heat absorbed by the heat conduction oil is low, the flue gas heat exchange device, the crucible cooling device and the transformer heat exchange device are closed, and electricity generated by the semiconductor temperature difference power generation device is stored in the energy storage power supply;

along with the smelting, the input power of the electrode is gradually increased, and the heat productivity of the transformer is gradually increased; the flue gas heat exchange device is started, the flue gas heat exchange device absorbs heat of the flue gas and transmits the heat to the semiconductor temperature difference power generation device for temperature difference power generation, and meanwhile, the semiconductor temperature difference power generation device supplies power to the flue gas heat exchange device; starting a transformer heat exchange device, absorbing heat emitted by a transformer through the transformer heat exchange device, transferring the heat to a semiconductor temperature difference power generation device for temperature difference power generation, and simultaneously supplying power to the transformer heat exchange device through the semiconductor temperature difference power generation device;

when smelting is carried out in the middle and later stages, the input power of the electrode is high, the heat productivity of the transformer is high, the temperature of the flue gas is high, and the flue gas heat exchange device and the transformer heat exchange device are continuously started to carry out temperature difference power generation; moreover, the heat of the heat conduction oil is gradually transferred to the phase-change heat-absorbing material, and partial heat is stored through the phase-change heat-absorbing material; starting a multipoint balance heat exchange water-cooling protector to take away partial heat of heat conducting oil at the side of the transformer to protect the transformer;

after smelting is finished, the air cooling fan and the crucible water cooling device are started, the semiconductor temperature difference power generation device supplies power to the air cooling fan and the crucible water cooling device, and the air cooling fan and the crucible water cooling device are started to carry out gas-water combined quenching on the crucible.

Compared with the prior art, the invention has the following beneficial effects:

the heat recovery crucible cooling system for electric arc furnace steelmaking efficiently recovers high-temperature flue gas of a flue and high-temperature heat of a transformer and other local positions through the coupling effect of the phase-change material and the heat pipe; in the smelting process, the semiconductor temperature difference power generation device is utilized to generate electricity and drive subsequent water cooling and air forced convection, so that a crucible in a hearth of the electric arc furnace is cooled quickly and taken out conveniently, and the final experimental result is not influenced by adverse reactions such as oxidation caused by long-time exposure of product materials in the air. The heat recovery crucible cooling system for the electric arc furnace steelmaking solves a series of problems that in the smelting process of a laboratory semi-industrial electric arc furnace, the heat of local parts is too high, the local parts are easy to overheat and burn, the heat loss of flue gas is serious, the temperature of a crucible is too high, the crucible is not easy to take out, the smelting process is influenced and the like.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a conventional laboratory semi-industrial dc arc furnace.

FIG. 2 is a schematic view of the heat recovery crucible cooling system of the present invention.

FIG. 3 is a schematic structural diagram of a flue gas heat exchange device and a semiconductor thermoelectric power generation device in the heat recovery crucible cooling system of the present invention.

FIG. 4 is a schematic structural diagram of a flue gas heat exchange tube in the heat recovery crucible cooling system of the present invention.

FIG. 5 is a schematic view of a connection structure of a wind cooling fan and a hearth in the heat recovery crucible cooling system of the present invention.

FIG. 6 is a schematic view of the installation structure of the water-cooling spiral tube and the crucible in the heat recovery crucible cooling system of the present invention.

FIG. 7 is a schematic structural view of a crucible water cooling device in the heat recovery crucible cooling system of the present invention.

Fig. 8 is a schematic structural view of a heat recovery crucible cooling system according to the present invention, in which a plurality of transformer-side spiral heat exchange tubes are combined in series.

FIG. 9 is a schematic view of the internal structure of a spiral heat exchange tube on the transformer side in the heat recovery crucible cooling system of the present invention.

FIG. 10 is a schematic view showing the internal structure of the semiconductor thermoelectric power generation device in the heat recovery crucible cooling system of the present invention.

Fig. 11 is a schematic structural view of a plurality of semiconductor thermoelectric generation units in series combination in the heat recovery crucible cooling system of the present invention.

FIG. 12 is a schematic structural diagram of a tee in the heat recovery crucible cooling system of the present invention.

Wherein the figures include the following reference numerals:

1. a flue gas heat exchange device; 11. a flue gas side heat conduction oil pool; 12. a flue gas heat exchange pipe; 13. a heat conducting oil outlet pipeline of the smoke side heat conducting oil pool; 14. a heat conducting oil inlet pipeline of the smoke side heat conducting oil pool; 15. a high-temperature heat pipe of the smoke side heat conduction oil pool; 16. a flue gas side guide hot oil pump; 17. a metal Seebeck effect temperature measuring tube of the smoke side heat conduction oil pool; 18. a flue gas metal Seebeck effect temperature measuring tube; 19. a three-way pipe; 121. a flue gas heat exchange inner pipe; 122. a flue gas heat exchange outer pipe; 123. a high-temperature heat pipe is arranged between the smoke side interlayers; 124. the flue gas side guides a hot oil channel; 131. a heat conducting oil outlet pipeline valve of the heat conducting oil pool at the smoke side; 132. a tee pipe inlet valve; 141. a three-way pipe outlet valve; 161. a smoke side guide hot oil pump control valve;

2. a semiconductor thermoelectric power generation device; 21. high temperature side conductive thermal ceramics; 22. a high-temperature-side metal plate; 23. an N-type semiconductor; 24. a P-type semiconductor; 25. a low-temperature-side metal plate; 26. low temperature side conductive thermal ceramics; 27. an energy storage power supply; 28. a semiconductor thermoelectric generation box; 29. a heat conducting oil pool support plate; 281. the hollow side of the semiconductor thermoelectric generation box; 282. a semiconductor thermoelectric generation box support frame; 283. a constant temperature standard liquid box;

3. a crucible cooling device; 31. an air-cooled fan; 32. a rotating mechanism; 33. a crucible water cooling device; 331. a closed circulation water tank; 332. a crucible water-cooling spiral pipe; 333. a water-cooled water supply pipe for the crucible; 334. a water-cooling return pipe of the crucible; 335. a crucible water-cooling water supply pump; 336. a crucible water-cooling water supply control valve;

4. a transformer heat exchange device; 41. a transformer side heat conduction oil pool; 42. a transformer side spiral heat exchange tube; 43. a transformer side hot oil guiding and returning pipeline; 44. the side of the transformer is provided with a hot oil outlet pipeline; 45. a metal Seebeck effect temperature measuring tube of a transformer side heat conduction oil pool; 46. a high-temperature heat pipe of the transformer side heat conduction oil pool; 47. a transformer side heat conduction oil pump; 48. a multipoint balance heat exchange water-cooling protector; 49. a transformer side hot oil conducting and discharging pipeline; 421. a transformer side heat exchange inner tube; 422. a transformer side heat exchange outer tube; 423. the side of the transformer is provided with a hot oil conducting channel; 424. a threaded bayonet; 431. a transformer side hot oil guiding and returning pipeline valve; 441. a transformer side hot oil guiding and discharging pipeline valve; 471. a control valve of a side-guide hot oil pump of the transformer; 491. a transformer side hot oil conducting and discharging pipeline valve;

100. a flue; 101. a dust collection cover; 102. a hearth; 103. a crucible; 104. a transformer rectifier cover; 105. a transformer; 106. and an electrode.

Detailed Description

In order to facilitate an understanding of the invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of the invention is not limited to the specific embodiments below. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The use of "first," "second," and similar terms in the description and in the claims of the present application do not denote any order, quantity, or importance, but rather the intention is to distinguish one element from another. Also, the use of the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.

Referring to fig. 2 to 12, a heat recovery crucible cooling system for steelmaking in an electric arc furnace according to an embodiment of the present invention mainly includes a flue gas heat exchanging device 1, a semiconductor thermoelectric power generation device 2, and a crucible cooling device 3. The flue gas heat exchange device 1 is connected with a flue 100 and a dust collection hood 101 of the electric arc furnace, and is used for recovering heat in high-temperature flue gas and transferring the heat to the semiconductor temperature difference power generation device 2; the high-temperature side of the semiconductor temperature difference power generation device 2 is connected with the flue gas heat exchange device 1 and is used for receiving heat transferred by the flue gas heat exchange device 1 and carrying out temperature difference power generation by utilizing the heat; the semiconductor thermoelectric power generation device 2 is connected to a crucible cooling device 3 for supplying power to the crucible cooling device 3, and the crucible cooling device 3 is used for quenching a crucible 103 of the electric arc furnace after smelting is finished.

Foretell heat recovery crucible cooling system for electric arc furnace steelmaking is retrieved the flue gas heat in flue 100 and the dust cage 101 of electric arc furnace through setting up flue gas heat transfer device 1, carries out thermoelectric generation with the flue gas heat transfer who retrieves to semiconductor thermoelectric generation device 2 to supply power for crucible cooling device 3 through semiconductor thermoelectric generation device 2, carry out the rapid cooling to the crucible 103 of electric arc furnace after smelting through crucible cooling device 3. This heat recovery crucible cooling system can retrieve the electricity generation to the heat of high temperature flue gas, and drive crucible cooling device 3 carries out the rapid cooling to crucible 103, has not only effectively reduced the flue gas temperature, has realized waste heat utilization, has avoided extra energy loss and waste, can cool off crucible 103 fast after smelting the end in addition, and the crucible 103 of being convenient for takes out, has shortened steelmaking experiment flow and time, has guaranteed simultaneously that the product material can not take place the oxidation because of exposing in the air for a long time.

Referring to fig. 2 and 3, the flue gas heat exchange device 1 mainly includes a flue gas side heat conduction oil pool 11, a flue gas heat exchange tube 12, a flue gas side heat conduction oil pool heat conduction oil outlet pipeline 13, a flue gas side heat conduction oil pool heat conduction oil inlet pipeline 14, and a flue gas side heat conduction oil pool high temperature heat pipe 15. Wherein, the flue gas side heat conduction oil pool 11 is connected with a flue gas side heat conduction oil pool high-temperature heat pipe 15, and the other end of the flue gas side heat conduction oil pool high-temperature heat pipe 15 is connected with the high-temperature side of the semiconductor temperature difference power generation device 2; the flue gas heat exchange tube 12 is arranged in the flue 100 and the dust collection cover 101, a flue gas heat exchange tube heat conduction oil inlet is formed in the upper end of the flue 100 of the flue gas heat exchange tube 12, and a flue gas heat conduction oil outlet is formed in the lower end of the dust collection cover 101 of the flue gas heat exchange tube 12; one end of a heat conduction oil outlet pipeline 13 of the smoke side heat conduction oil pool is connected with the smoke side heat conduction oil pool 11, the other end of the heat conduction oil outlet pipeline 13 of the smoke side heat conduction oil pool is connected with a heat conduction oil inlet of a smoke heat exchange pipe 12 of the smoke heat exchange pipe 12, and a smoke side heat conduction oil pump 16 is further installed on the heat conduction oil outlet pipeline 13 of the smoke side heat conduction oil pool; one end of a heat conduction oil inlet pipeline 14 of the smoke side heat conduction oil pool is connected with the smoke side heat conduction oil pool 11, and the other end of the heat conduction oil inlet pipeline 14 of the smoke side heat conduction oil pool is connected with a heat conduction oil outlet of a smoke heat exchange tube of the smoke heat exchange tube 12.

The flue gas heat exchange device 1 has the main function of efficiently recovering heat from flue gas generated in the steelmaking process of an electric arc furnace and transferring the heat of the flue gas to the semiconductor temperature difference power generation device 2. This flue gas heat transfer device 1 during operation, the heat of high temperature flue gas in flue gas absorption flue 100 and the dust cage 101 is absorbed to the conduction oil in flue gas heat exchange tube 12, the conduction oil after absorbing the flue gas heat gets into flue gas side heat conduction oil bath 11, heat transfer to semiconductor thermoelectric generation device 2's high temperature side through flue gas side heat conduction oil bath high temperature heat pipe 15, semiconductor thermoelectric generation device 2 utilizes this heat to carry out thermoelectric generation, and for the power supply of flue gas side heat conduction oil pump 16, drive the conduction oil circulation flow through flue gas side heat conduction oil pump 16, continuously absorb the flue gas heat.

Referring to fig. 4, in the present embodiment, the flue gas heat exchange pipe 12 includes a flue gas heat exchange inner pipe 121, a flue gas heat exchange outer pipe 122 and a flue gas side interlayer high temperature heat pipe 123. Wherein, the phase change heat absorption material is filled in the flue gas heat exchange inner tube 121; the flue gas heat exchange outer pipe 122 is sleeved outside the flue gas heat exchange inner pipe 121, and flue gas side hot oil conducting channels 124 for heat conducting oil to flow through are formed between the flue gas heat exchange outer pipe 122 and the flue gas heat exchange inner pipe 121 at intervals; one end of the flue gas heat exchange outer pipe 122 is connected with a flue gas side heat transfer oil pool heat transfer oil outlet pipeline 13, and the other end thereof is connected with a flue gas side heat transfer oil pool heat transfer oil inlet pipeline 14; the flue gas side interlayer high-temperature heat pipe 123 is arranged in the flue gas side heat conduction oil channel 124, and the flue gas side interlayer high-temperature heat pipe 123 extends out of the flue gas heat exchange outer pipe 122 and is connected with the high-temperature side of the semiconductor temperature difference power generation device 2.

Due to the fact that the heat carrying capacity of the heat conduction oil is limited, when the temperature of the smoke is too high, part of heat can be gradually transferred to the phase-change heat absorption material in the smoke heat exchange inner tube 121 through the heat conduction oil, the solid phase-change heat absorption material is heated to reach the melting point of the phase-change heat absorption material, the solid phase-change heat absorption material can be gradually melted, a large amount of heat is absorbed until the solid phase-change heat absorption material is completely changed into a liquid state, and a large amount of heat can be stored through the phase-change heat absorption material. In addition, the flue gas side interlayer high-temperature heat pipe 123 arranged in the flue gas side hot oil conducting channel 124 can also transfer part of heat of the heat conducting oil in the flue gas side hot oil conducting channel 124 to the high-temperature side of the semiconductor thermoelectric power generation device 2, so that the phase change material-heat pipe-heat conducting oil coupling heat recovery is realized.

In this embodiment, the flue gas side heat conduction oil pool 11 is further connected with a metal seebeck effect temperature measurement tube 17, one end of the metal seebeck effect temperature measurement tube 17 extends into the flue gas side heat conduction oil pool 11 to receive heat of the heat conduction oil as a hot end, and the other end of the metal seebeck effect temperature measurement tube 17 is connected with the high-temperature side of the semiconductor thermoelectric power generation device 2. The temperature of the heat conduction oil in the smoke side heat conduction oil pool 11 can be detected through the metal Seebeck effect temperature measurement tube 17 of the smoke side heat conduction oil pool, and power generation can be carried out through the metal Seebeck effect.

A smoke metal Seebeck effect temperature measuring tube 18 is further arranged in the dust hood 101, one end of the smoke metal Seebeck effect temperature measuring tube 18 extends into the middle position of the bottom of the dust hood 101 and receives high-temperature heat of smoke as a hot end, and the other end of the smoke metal Seebeck effect temperature measuring tube 18 is connected with the high-temperature side of the semiconductor temperature difference power generation device 2. So set up, can detect the flue gas temperature through this flue gas metal seebeck effect temperature tube 18 to can also generate electricity through the metal seebeck effect.

Referring to fig. 2 and 3, a heat-conducting oil inlet of the flue gas heat exchange tube 12 is detachably connected with a heat-conducting oil outlet pipeline 13 of the flue gas side heat-conducting oil pool through a three-way pipe 19; the heat conducting oil outlet of the flue gas heat exchange tube 12 is also detachably connected with the heat conducting oil inlet pipeline 14 of the flue gas side heat conducting oil pool through a three-way pipe 19. Due to the arrangement, the flue gas heat exchange tube 12 can be conveniently cleaned and replaced; one interface of the three-way pipe 19 is communicated with the atmosphere, and the flue gas heat exchange pipe 12 can be communicated with the atmosphere by opening the interface, so that the outflow of heat conducting oil in the flue gas heat exchange pipe 12 is accelerated; and the interface can be used as an inlet and an outlet of the heat conduction oil to perform operations such as flowing out and replacing the heat conduction oil.

Referring to fig. 5, the crucible cooling device 3 includes an air cooling fan 31, the air cooling fan 31 is connected to the semiconductor thermoelectric power generation device 2, and the air cooling fan 31 is powered by the semiconductor thermoelectric power generation device 2; the air cooling fan 31 is rotatably mounted on the furnace chamber 102 of the electric arc furnace by a rotating mechanism 32. In the smelting process, in order to prevent the air cooling fan 31 from being locally heated, the air cooling fan 31 can be vertically placed downwards; once smelting is finished and forced convection heat transfer is needed, the air cooling fan 31 can rotate to the furnace door through the rotating mechanism 32 to blow and quench the crucible 103.

Referring to fig. 6 and 7, the crucible cooling device 3 further includes a crucible water-cooling device 33, and the crucible water-cooling device 33 includes a closed circulation water tank 331 and a crucible water-cooling coil 332. Wherein, the closed circulation water tank 331 is connected with both ends of the crucible water-cooling spiral pipe 332 through a crucible water-cooling water supply pipe 333 and a crucible water-cooling water return pipe 334, respectively; the crucible water-cooling spiral pipe 332 is sleeved on the crucible 103 of the electric arc furnace and used for cooling the crucible 103 by water cooling; the crucible water-cooling water supply pipe 333 is further provided with a crucible water-cooling water supply pump 335 for supplying circulating cooling water to the crucible water-cooling spiral pipe 332, and the semiconductor thermoelectric power generation device 2 is connected to the crucible water-cooling water supply pump 335 for supplying power to the crucible water-cooling water supply pump 335. With the arrangement, after smelting is finished, water in the closed circulating water tank 331 is introduced into the crucible water-cooling spiral pipe 332 through the crucible water-cooling water supply pump 335 to cool the crucible 103, and a large amount of heat of the crucible 103 is taken away through dividing wall type heat exchange of the water.

In the steelmaking process of the electric arc furnace, the transformer 105 is required to supply power to the electrode 106, parts such as the transformer 105 in the smelting process generate heat seriously, so that the risk of burning loss exists, excessive local heat is concentrated to be very unfavorable for the smelting process, and local waste heat is difficult to be directly utilized in the smelting process, so that extra energy loss and waste are caused. In order to solve the above problem, in this embodiment, the heat recovery crucible cooling system further includes a transformer heat exchanging device 4, and the transformer heat exchanging device 4 includes a transformer side heat conducting oil pool 41, a transformer side spiral heat exchanging tube 42, a transformer side heat conducting oil return pipeline 43, a transformer side heat conducting oil outlet pipeline 44, and a transformer side heat conducting oil pool metal seebeck effect temperature measuring tube 45. Wherein, the transformer side heat conduction oil pool 41 is connected with a transformer side heat conduction oil pool high temperature heat pipe 46, and the other end of the transformer side heat conduction oil pool high temperature heat pipe 46 is connected with the high temperature side of the semiconductor temperature difference power generation device 2; the transformer-side spiral heat exchange tube 42 is installed in a transformer rectifier cover 104 of the arc furnace for recovering heat of a transformer 105; one end of a transformer side hot oil conducting and returning pipeline 43 is connected with the transformer side hot oil conducting pool 41, and the other end of the transformer side hot oil conducting and returning pipeline is connected with an oil outlet of a transformer side spiral heat exchange pipe 42; a transformer side heat conduction oil pump 47 and a multipoint balance heat exchange water cooling protector 48 are also arranged on the transformer side heat conduction oil return pipeline 43; one end of the transformer side hot oil conducting and discharging pipeline 44 is connected with the transformer side hot oil conducting pool 41, and the other end thereof is connected with an oil inlet of the transformer side spiral heat exchange pipe 42; one end of the transformer side heat conduction oil pool metal seebeck effect temperature measurement tube 45 extends into the transformer side heat conduction oil pool 41, and the other end thereof is connected with the high temperature side of the semiconductor temperature difference power generation device 2.

So set up, when needs cool down the cooling to transformer 105, carry the conduction oil in the transformer side heat conduction oil bath 41 to the transformer side spiral heat exchange tube 42 in through transformer side heat conduction oil pump 47, absorb the heat of transformer 105 rectifier department through the conduction oil, then the conduction oil carries the heat and gets into transformer side heat conduction oil bath 41, the high temperature side of conduction oil heat transfer to semiconductor thermoelectric generation device 2 in transformer side heat conduction oil bath 41 is through transformer side heat conduction oil bath high temperature heat pipe 46 to the rethread, semiconductor thermoelectric generation device 2 utilizes this heat to carry out thermoelectric generation. When the transformer 105 is cooled, the waste heat of the transformer 105 is utilized, and the transformer 105 is prevented from being damaged due to overheating.

Specifically, referring to fig. 8 and 9, the transformer-side spiral heat exchange tube 42 includes a transformer-side heat exchange inner tube 421 and a transformer-side heat exchange outer tube 422. A phase change heat absorption material is filled in the transformer side heat exchange inner tube 421; the transformer side heat exchange outer tube 422 is sleeved outside the transformer side heat exchange inner tube 421, and the transformer side heat exchange outer tube 422 and the transformer side heat exchange inner tube 421 are spaced to form a transformer side heat conduction oil channel 423 for heat conduction oil to flow through; one end of the transformer side heat exchange outer tube 422 is connected to the transformer side hot oil return pipeline 43, and the other end thereof is connected to the transformer side hot oil return pipeline 44. When the temperature of the transformer 105 is too high, part of the heat can be gradually transferred from the heat conduction oil to the phase-change heat-absorbing material in the transformer-side heat exchange inner tube 421, the solid phase-change heat-absorbing material is heated to reach the melting point thereof, gradually melted, and absorbs a large amount of heat until the solid phase-change heat-absorbing material is completely changed into the liquid state, and the phase-change heat-absorbing material can store a large amount of heat.

Further, referring to fig. 8, the transformer heat exchanging device 4 includes a plurality of transformer side spiral heat exchanging pipes 42, and the plurality of transformer side spiral heat exchanging pipes 42 are detachably connected in series via threaded bayonets 424 with the transformer side hot oil returning pipe 43 and the transformer side hot oil returning pipe 44. With this arrangement, a suitable number of the transformer side spiral heat exchange tubes 42 can be selectively connected as required, and maintenance and replacement can be facilitated when some of the transformer side spiral heat exchange tubes 42 are damaged.

Referring to fig. 10 and 11, the semiconductor thermoelectric generation device 2 includes a high-temperature-side heat-conductive ceramic 21, a high-temperature-side metal plate 22, an N-type semiconductor 23, a P-type semiconductor 24, a low-temperature-side metal plate 25, a low-temperature-side heat-conductive ceramic 26, and an energy storage power supply 27. Wherein, the high-temperature side heat-conducting ceramic 21 is the high-temperature side of the semiconductor thermoelectric power generation device 2, and the high-temperature side heat-conducting ceramic 21 is uniformly connected with the flue gas side heat-conducting oil pool high-temperature heat pipe 15, the flue gas side heat-conducting oil pool metal seebeck effect temperature measuring pipe 17, the flue gas metal seebeck effect temperature measuring pipe 18, the flue gas side interlayer high-temperature heat pipe 123, the transformer side heat-conducting oil pool metal seebeck effect temperature measuring pipe 45, the transformer side heat-conducting oil pool high-temperature heat pipe 46 and the like; the high-temperature side heat-conducting ceramic 21 is connected with the high-temperature side metal plate 22; the N-type semiconductor 23 and the P-type semiconductor 24 are both connected to the high-temperature-side metal plate 22; the other ends of the N-type semiconductor 23 and the P-type semiconductor 24 are connected to a low-temperature-side metal plate 25, respectively; the two low-temperature-side metal plates 25 are connected with a low-temperature-side heat-conducting ceramic 26; the two low-temperature side metal plates 25 are respectively connected with an energy storage power supply 27 through a conducting wire.

With the arrangement, heat is transferred to the high-temperature side heat conducting ceramic 21 and then to the high-temperature side metal plate 22 through the temperature measuring tubes and the high-temperature heat pipe, one end of the low-temperature side metal plate 25 and one end of the low-temperature side heat conducting ceramic 26 are the low-temperature side, the N-type semiconductor 23 and the P-type semiconductor 24 generate electricity by using the temperature difference between the two sides, and electric energy is stored in the energy storage power supply 27. The energy storage power supply 27 supplies power to the flue gas side hot oil pump 16, the air cooling fan 31, the crucible water cooling water supply pump 335, the transformer side hot oil pump 47 and the like.

Further, referring to fig. 11, a semiconductor thermoelectric generation device 2, which is composed of a high temperature side metal plate 22, an N-type semiconductor 23, a P-type semiconductor 24 and two low temperature side metal plates 25 together to constitute a semiconductor thermoelectric generation unit, includes a plurality of the above semiconductor thermoelectric generation units, and a plurality of the semiconductor thermoelectric generation units are connected in series. Therefore, larger generating capacity can be obtained, and the method is more suitable for actual needs.

A transformer side hot oil pump control valve 471 may be provided in front of and behind the transformer side hot oil pump 47, a flue gas side hot oil pump control valve 161 may be provided in front of and behind the flue gas side hot oil pump 16, and a crucible water cooling water supply control valve 336 may be provided in front of and behind the crucible water cooling water supply pump 335. Therefore, the corresponding pump can be protected, the water hammer phenomenon is reduced, and the corresponding pump can be conveniently maintained, replaced and the like.

For the transformer side hot oil conducting circulation loop, a transformer side hot oil conducting and returning pipeline valve 431 can be arranged on the transformer side hot oil conducting and returning pipeline 43; the tail end of the transformer side hot oil guiding and returning pipeline 43 is connected with a transformer side hot oil guiding and discharging pipeline 49, and a transformer side hot oil guiding and discharging pipeline valve 491 is arranged on the transformer side hot oil guiding and discharging pipeline 49; a transformer side hot oil outlet pipeline valve 441 is arranged on the transformer side hot oil outlet pipeline 44; the main function of the device is to control the on-off of corresponding pipelines, and simultaneously, the device also has the flow regulation function, thereby being convenient for controlling the flow of the heat conduction oil of the transformer side heat conduction oil circulation loop in real time and indirectly controlling the transmission of heat.

For the flue gas side conduction oil circulation loop, a flue gas side conduction oil pool conduction oil outlet pipeline valve 131 can be arranged on the flue gas side conduction oil pool conduction oil outlet pipeline 13, a three-way pipe inlet valve 132 is arranged at the position, close to the three-way pipe 19, of the flue gas side conduction oil pool conduction oil outlet pipeline 13, and a three-way pipe outlet valve 141 is arranged at the position, close to the three-way pipe 19, of the flue gas side conduction oil pool conduction oil inlet pipeline 14; the device has the main function of controlling the on-off of the corresponding pipeline, has a flow regulation function, and is convenient for controlling the flow of heat conduction oil of the flue gas side heat conduction oil circulation loop in real time, thereby indirectly controlling the transmission of heat. For these valves, high temperature resistance is required.

In the invention, the heat conducting oil is selected as a medium for circulating each pipeline, mainly because the heat conducting oil has stable property, does not gasify under the high temperature condition, simultaneously does not change the heat transfer capacity, the physical property and the chemical property which are shown under different temperatures greatly, is safe and reliable, has certain air isolation capacity, and can play a certain protection role on the pipeline and the valve through which the heat conducting oil flows, so the service life of corresponding equipment can be prolonged, and the heat conducting oil is suitable for heat transmission in the high-temperature smelting process of the electric arc furnace.

The transformer side hot oil conducting and discharging pipeline 49 is arranged at the lowest end of the transformer side hot oil conducting circulation loop, and mainly has the main function that when the heat conducting oil circulating in the pipeline needs to be replaced due to the problem of service life, the valve 491 of the transformer side hot oil conducting and discharging pipeline can be opened, so that the heat conducting oil at the transformer side can be discharged, and the replacement of new heat conducting oil is facilitated.

The transformer 105 is mainly used for converting alternating current of a pipe network into direct current within a specific range for the electric arc furnace to use, and determines energy input in the steel making process of the electric arc furnace.

Transformer rectifier cover 104 is located the top of transformer 105's main position rectifier that generates heat, can take off at any time or load on, its matter is light, there is not special requirement to the material, can steadily place the top at transformer 105 rectifier, be a cuboid type cavity, its main function is that isolated laboratory is with the material such as smoke and dust that produces in the semi-industrial direct current electric arc furnace smelting process, it is too much to prevent rectifier top laying dust, aggravate local overheat and burning loss, also have in the electric arc furnace smelting process simultaneously such as material scattering on the transmission line such as rectifier such as graphite refined powder, cause transformer 105 short circuit.

The closed circulation water tank 331 is a water supply point of a water cooling link in the gas-water combined quenching device, is directly connected with a water supply network, does not need to be large in volume, and can save part of space. Meanwhile, the closed circulating water tank 331 cannot contact with dust-containing gas in the air, so that the phenomena of poor water quality, increased impurities, corrosion of the water tank, pipeline blockage, poor heat exchange capacity and the like caused by the fact that impurities such as smoke dust, materials and the like enter the water tank in the smelting process of the electric arc furnace are reduced.

The semiconductor thermoelectric power generation device 2 further comprises a semiconductor thermoelectric power generation box 28, a semiconductor thermoelectric power generation box hollow side 281 is arranged on the semiconductor thermoelectric power generation box 28, a semiconductor thermoelectric power generation box support frame 282 is arranged below the semiconductor thermoelectric power generation box 28, and a constant temperature standard liquid box 283 is arranged in the semiconductor thermoelectric power generation box 28. The main function of the semiconductor thermoelectric generation box support frame 282 is to provide a support function for the semiconductor thermoelectric generation box 28 and the two heat-conducting oil pools, and has certain structural strength for the requirements, and the specific appearance or structure of the semiconductor thermoelectric generation box support frame can be determined according to the arrangement condition of the specific device of the laboratory semi-industrial direct-current arc furnace.

The constant-temperature standard liquid box 283 is mainly used for containing liquid with unchanged temperature, normal-temperature liquid water can be used under the limited experimental conditions, cold end leads of all metal Seebeck effect temperature measuring tubes extend into the constant-temperature standard liquid box 283 to be constant in temperature, the temperature of the normal-temperature liquid water can be converted according to a data chart of a standard thermocouple only by determining the temperature of the normal-temperature liquid water, the temperature signal is converted into a current signal and then converted into a temperature signal again, and the temperature of a corresponding temperature measuring area can be obtained. The reason why the temperature of the liquid water is not changed is to keep the cold end of the metal Seebeck effect at a constant temperature, and the temperature of the hot end is changed to form different current signals in a loop so as to feed back a temperature signal.

The main purpose of the hollow side 281 of the semiconductor thermoelectric generation box is to allow the low-temperature side (cold end) of the semiconductor thermoelectric generation device 2 to be in direct contact with ambient air, maintain the lower temperature of the cold end, and facilitate the generation of electricity under the condition of larger temperature difference.

The device comprises a smoke side heat conduction oil pool metal Seebeck effect temperature measurement pipe 17, a smoke side heat conduction oil pool high-temperature heat pipe 15, a transformer side heat conduction oil pool high-temperature heat pipe 46, a smoke side interlayer high-temperature heat pipe 123, a smoke metal Seebeck effect temperature measurement pipe 18 and a transformer side heat conduction oil pool metal Seebeck effect temperature measurement pipe 45, wherein the heat pipes or the metal Seebeck effect temperature measurement pipes are movably connected with a semiconductor temperature difference power generation box 28, and during the working and running of the device, only the corresponding high-temperature heat pipes and the temperature measurement pipes are required to be clamped inside a high-temperature side heat conduction ceramic 21, so that the situation that loosening or sliding does not occur is guaranteed, gaps are not reserved as much as possible, air is prevented from entering, and the heat transfer effect is reduced. The connection does not need screw thread and fixed connection, so as to facilitate the installation of the device and the replacement and maintenance of accessories such as high-temperature heat pipes and the like to the maximum extent.

Meanwhile, the connection mode of the high-temperature heat pipes and the temperature measuring pipes and the corresponding heat conducting oil pool is movably connected, namely the high-temperature heat pipes and the temperature measuring pipes are positioned in the heat conducting oil pool to a certain depth, but are not in contact with the bottom or the side wall of the heat conducting oil pool, and are fixed on the upper part of the heat conducting oil pool by virtue of the bayonet, so that the integral structure is ensured not to loosen and slide, and meanwhile, the high-temperature heat pipes and the temperature measuring pipes are convenient to take out, replace or perform related maintenance work.

The connection mode of the flue gas side interlayer high-temperature heat pipe 123 and the flue gas heat exchange pipe 12 in the flue 100 and the dust collection cover 101 is movably connected, but the movable connection requirement at the position is higher, it needs to be ensured that heat conduction oil cannot leak at the joint, meanwhile, a high-temperature-resistant sealing washer is suggested to be adopted at the joint for treatment, leakage is avoided, when the high-temperature heat pipe needs to be replaced or maintained, the heat conduction oil needs to be firstly recovered to a heat conduction oil pool, then the original heat pipe is pulled out, and operations such as replacement, maintenance and the like are carried out.

The multipoint balance heat exchange water-cooling protector 48 mainly has the function of preventing the rectifier and other parts of the transformer 105 from generating great resistance heat when the input electric energy is great in the smelting process of the electric arc furnace, and once the heat carrying capacity of heat conducting oil and the heat storage capacity of phase change materials reach the maximum limit, the branch of the multipoint balance heat exchange water-cooling protector 48 is opened in time to carry out dividing wall water-cooling on the heat conducting oil, so that the normal work of the transformer 105 is ensured, and local overheating and burning loss occur.

The transformer side heat conduction oil pool 41 and the flue gas side heat conduction oil pool 11 are two completely independent heat conduction oil pools, and the two heat conduction oil pools are separated by a partition plate and do not interfere with each other, so that heat exchange can be allowed at the partition plate where the two heat conduction oil pools are connected. The two heat conduction oil pools are arranged mainly because the heat recovered from the transformer side and the high-temperature flue gas side is different, the required heat conduction oil flow is different, and in order to avoid introducing redundant accessories such as a flow distribution device, the two heat conduction oil pools are divided to recover heat of heat sources with different tastes.

Two heat conduction oil ponds are installed on a heat conduction oil pond backup pad 29, and the complete rigid coupling of one end of heat conduction oil pond backup pad 29 is on semiconductor thermoelectric generation case support frame 282, need keep holistic intensity simultaneously, can resist the dead weight of transformer side heat conduction oil pond 41 and flue gas side heat conduction oil pond 11, keeps certain intensity.

The three-way pipe 19 is mainly used for conveying heat conduction oil for the subsequent flue gas heat exchange pipe 12. The other end of the three-way pipe 19 is communicated with the atmosphere, and the three-way pipe is mainly used for facilitating the replacement operation of heat conduction oil at the side of the flue, accelerating the outflow of the heat conduction oil in the flue gas heat exchange pipe 12, and meanwhile, the three-way pipe can also be used as an outlet for performing the operations of outflow, replacement and the like of the heat conduction oil. The last end of the three-way pipe 19 is connected with the flue gas heat exchange pipe 12 for conveying heat conducting oil. The three-way pipe 19 is in threaded connection with the flue gas heat exchange pipe 12, the flue gas side hot oil conducting pool heat conducting oil inlet pipeline 14 and the flue gas side hot oil conducting pool heat conducting oil outlet pipeline 13 through threaded bayonets, and the two pipelines can be disconnected by rotating the threaded bayonets, so that the disassembly, assembly and replacement are convenient.

The phase-change heat-absorbing material can be a crystalline hydrated salt material, and the phase-change material is mainly used for storing waste heat at a high-temperature flue gas side and a transformer side, so that release of subsequent links is facilitated. Because the sensible heat of waste heat is more in the steelmaking process of the electric arc furnace, a crystalline hydrated salt material is selected as a phase-change material. However, the phase-change material of the crystalline hydrous salt has the limitation of the phase-change times, and needs to be replaced after being used for a period of time, so each movable screw bayonet should be provided with the screw bayonet of the inner tube of the sleeve structure, and after the connection of the movable screw bayonets is disconnected, the main purpose is to expose the phase-change material in the inner tube, so that the replacement operation is convenient.

The flue gas heat exchange tube 12 is spirally wound on the inner side of the flue 100 and the dust collection cover 101, is preferably made of a copper tube, is in close contact with the flue 100 and the dust collection cover 101, and is generally fixedly connected inside the flue 100 and the dust collection cover 101, but the fixing strength of the flue gas heat exchange tube is not large, and only the momentum impact generated by the dead weight and the flow of heat conduction oil in the pipeline and the thermal stress of high-temperature flue gas need to be overcome. When necessary, when the copper pipe of the flue gas heat exchange pipe 12 is corroded or the dust collection is too large, the flue gas heat exchange pipe 12 can be taken down from the inside of the flue 100 by external force by disconnecting the threaded bayonet at the three-way pipe 19, so that the flue gas heat exchange pipe can be cleaned and replaced.

The flue gas heat exchange tube 12 is of a double-layer sleeve structure, the inside of the flue gas heat exchange inner tube 121 is filled with phase change materials, flowing heat conduction oil is arranged in a flue gas side heat conduction oil channel 124 between the flue gas heat exchange inner tube 121 and the flue gas heat exchange outer tube 122, and meanwhile, the flue gas side interlayer high-temperature heat tube 123 is also positioned in the interlayer and mainly absorbs heat of the heat conduction oil.

The energy storage power supply 27 mainly functions to store semiconductor thermoelectric power generation, and is required to be capable of discharging during charging, namely, suitable for occasions with frequent charging and discharging, and certainly also can allow an external power supply to charge the semiconductor thermoelectric power generation, and does not necessarily require the semiconductor thermoelectric power generation to be the only power source. Meanwhile, for the equipment needing electricity, such as the transformer side hot oil guide pump 47, the flue gas side hot oil guide pump 16, the crucible water cooling water supply pump 335, the air cooling fan 31 and the like, the power input sources are all from the energy storage power supply 27, and no external power supply is provided. The arrangement mode of the P-type semiconductor 24 and the N-type semiconductor 23 preferably adopts the series arrangement of semiconductor modules, so that larger power generation capacity can be obtained, and the actual requirement can be met.

The heated end of the smoke metal Seebeck effect temperature measuring tube 18 is positioned at the central position of the dust hood 101 and receives the high-temperature heat of the smoke as the hot end. The heated end of the metal Seebeck effect temperature measuring tube 17 of the smoke side heat conduction oil pool is positioned in the smoke side heat conduction oil pool 11 and receives the high-temperature heat of the heat conduction oil to be used as the hot end. The heated end of the transformer side heat conduction oil pool metal seebeck effect temperature measuring tube 45 is positioned in the transformer side heat conduction oil pool 41 and receives the high-temperature heat of the heat conduction oil as the hot end.

The power source of the semiconductor thermoelectric power generation device 2 is not only from the temperature difference formed by the heat transferred by the high-temperature heat pipe, but also from the potential difference generated in the semiconductor to form current, and meanwhile, the power generation by the metal seebeck effect is realized, and the power source should have two ways as shown in fig. 10.

The transformer side spiral heat exchange tube 42 is coiled at the side of the rectifier of the transformer 105, the structure of the transformer side spiral heat exchange tube is the same as that of the flue gas heat exchange tube 12, and the only difference is that the inside of the transformer side spiral heat exchange tube 42 only has heat conduction oil and phase change materials, but does not have a heat pipe with a sandwich layer. The rest of the structure is the same as that of the flue gas heat exchange tube 12.

Crucible water-cooling spiral pipe 332 is coiled on crucible 103, and crucible water-cooling spiral pipes 332 with different sizes can be customized according to the actual size of crucible 103, because the model of crucible 103 used in the actual laboratory with semi-industrial direct current electric arc furnace is relatively fixed, the size of crucible water-cooling spiral pipe 332 is only that. Depending on the actual size of crucible 103, different crucible water-cooling spiral pipes 332 can be connected by disconnecting the screw bayonet on crucible water-cooling spiral pipe 332. A large amount of heat of the crucible 103 is taken away by the dividing wall type heat exchange of water.

The air cooling fan 31 is connected to the hearth 102 of the semi-industrial direct current electric arc furnace for the laboratory through the rotating mechanism 32, the air cooling fan 31 can rotate through the rotating mechanism 32, and the air cooling fan 31 can be vertically placed downwards in order to prevent the local heating of the air cooling fan 31 in the smelting process; after smelting, when forced convection heat transfer is required, the air cooling fan 31 can be rotated to the furnace door to perform blowing quenching.

The heat recovery crucible cooling system for electric arc furnace steelmaking of the invention has comprehensive functions, integrates various functions of heat collection recovery, power generation, electric energy output, gas-water combined quenching and the like, and has the following working procedures:

(1) at the beginning stage of smelting with the semi-industrial direct current electric arc furnace in laboratory, to high temperature flue gas side, flue gas side hot oil conduction pool conduction oil outlet pipeline valve 131, flue gas side hot oil pump control valve 161, three-way pipe outlet valve 141, three-way pipe inlet valve 132 are all opened, and all the screws of each screw thread bayonet are locked, prevent that the conduction oil from revealing.

For the transformer side, the transformer side hot oil pump control valve 471, the transformer side hot oil guiding and returning pipeline valve 431 and the transformer side hot oil guiding and returning pipeline valve 441 are all opened, and the transformer side hot oil guiding and discharging pipeline valve 491 is closed; all the thread bayonets are screwed tightly and locked to prevent heat conducting oil from leaking.

Meanwhile, for the water cooling device, the crucible water cooling and supplying control valve 336 is closed to block the water cooling device from working.

At this stage, the input power of the electrode 106 is low, meanwhile, the sensible heat contained in the smoke is also low, the heat absorbed by the heat conduction oil is low, the transformer side heat conduction oil pump 47, the flue gas side heat conduction oil pump 16, the crucible water cooling water supply pump 335 and the air cooling fan 31 do not work, the generated energy of the semiconductor thermoelectric power generation device 2 is low, and all the generated energy is stored in the energy storage power supply 27.

(2) The input power of the electrode 106 is gradually increased along with the smelting

In this stage, the transformer side heat transfer oil pump 47 and the flue gas side heat transfer oil pump 16 both work normally, high-temperature flue gas from the flue 100 and the dust collection hood 101 heats heat transfer oil in the flue gas heat exchange tube 12, the heat transfer oil and the flue gas are equivalent to reverse heat exchange, the heat exchange efficiency is high, the heat transfer oil carries heat and enters the flue gas side heat transfer oil pool 11 through the three-way pipe 19, the heat is released to the high-temperature heat pipe 15 of the flue gas side heat transfer oil pool, the heat transfer oil after the heat is released continues to enter the flue gas heat exchange tube 12 in the flue 100 again along the flue gas side heat transfer oil pool heat transfer oil outlet pipeline 13, and the next round of circulation is performed.

After the heat is obtained to flue gas side heat conduction oil bath high temperature heat pipe 15, with its from the hot junction to the cold junction fast transfer, and then give high temperature side heat conduction pottery 21 and high temperature side metal sheet 22 with heat transfer, make its temperature rise, and low temperature side metal sheet 25 temperature is still lower, just so can form great difference in temperature at the both ends of P type semiconductor 24 and N type semiconductor 23, and then form the thermoelectric force in the return circuit, steadily transmit the current for energy storage power supply 27 through voltage regulator, form thermoelectric generation. While the energy storage power supply 27 continues to power the transformer side hot oil pump 47 and the flue gas side hot oil pump 16. In addition, the flue gas side interlayer high-temperature heat pipe 123 located in the flue gas side hot oil conducting channel 124 of the flue gas heat exchanging pipe 12 also continuously transmits heat to the hot end of the semiconductor temperature difference power generation device 2, so that a larger temperature difference is formed.

Along with the increase of input power at the transformer 105 side, the heat productivity of the rectifier is gradually increased, the heat conducting oil carrying the heat productivity of the rectifier enters the transformer side heat conducting oil pool 41 through the transformer side heat conducting oil outlet pipeline 44, the heat is released to the transformer side heat conducting oil pool high-temperature heat pipe 46, the heat conducting oil after the heat release continues to enter the transformer side spiral heat exchange pipe 42 again along the transformer side heat conducting oil return pipeline 43, and the next round of circulation is performed.

After obtaining heat, the high-temperature heat pipe 46 of the transformer side heat conduction oil pool quickly transfers the heat to the cold end from the hot end, and then transfers the heat to the high-temperature side heat conduction ceramic 21 and the high-temperature side metal plate 22, so that the temperature of the high-temperature side heat conduction ceramic rises, a large temperature difference is continuously formed at two ends of the P-type semiconductor 24 and the N-type semiconductor 23, and then a thermoelectromotive force is formed in a loop, and the generated energy is increased.

Meanwhile, the respective heated ends of the metal Seebeck effect temperature measuring tube 17 of the smoke side heat conduction oil pool, the metal Seebeck effect temperature measuring tube 18 of the smoke and the metal Seebeck effect temperature measuring tube 45 of the transformer side heat conduction oil pool are also heated by heat conduction oil and high-temperature smoke to form temperature difference electromotive force, and further power generation is realized.

The driving force of the thermoelectric force mainly comes from metal seebeck effect power generation and semiconductor thermoelectric power generation, the power source is abundant, and the transformer side-guided hot oil pump 47 and the flue gas side-guided hot oil pump 16 which mainly consume power at this stage have less heat in the heating link, so that the oil pump rotating speed is lower, the flowing speed of the heat-conducting oil is also lower, the power consumption is less, and the energy storage power supply 27 is in the process of continuously storing energy in general.

(3) When the smelting is carried out in the middle and later stages, the input power of the electrode 106 is larger, the heat productivity of the rectifier on the transformer 105 side is larger, and the temperature of the flue gas in the electric arc furnace flue 100 is higher.

In this stage, as described above, the temperature difference of the semiconductor thermoelectric power generation device 2 is also larger, and the power generation amount is also larger. Meanwhile, the heat carrying capacity of the heat conducting oil is limited, and heat can be gradually transferred to the phase change materials in the flue gas heat exchange inner tube 121 and the transformer side heat exchange inner tube 421. The solid phase-change material is heated to reach the melting point, and then gradually melts to absorb a large amount of heat until the solid phase-change material is completely changed into a liquid state, and a large amount of heat is stored. Meanwhile, the heat of the heat conducting oil can be continuously pumped away by the heat pipe.

However, once the temperature of the hot oil at the side of the transformer 105 is too high, the risk of overheat damage of the transformer 105 is increased significantly, and at this stage, the water-cooling protection device can be started to continuously take away the excess heat of the hot oil at the side of the transformer 105, so as to achieve the purpose of protecting the rectifier at the side of the transformer 105.

The most heat is recovered at this stage, so the semiconductor thermoelectric generation effect is the most remarkable, and the semiconductor thermoelectric generation effect is also the main electricity storage link of the energy storage power supply 27.

(4) After smelting, the electrode 106 does not input power any more and does not generate high-temperature flue gas, and the crucible water-cooling water supply pump 335 and the air-cooled fan 31 are driven by electricity generated previously to quench the crucible in the process. Certainly, part of the electric energy needs to be output to the transformer side heat transfer oil pump 47 and the flue gas side heat transfer oil pump 16, so that the heat transfer oil is ensured to have a certain flow rate, but the flow rate of the heat transfer oil is very low, and thus the effect of uniform heat distribution can be achieved.

Firstly, the hearth 102 of the laboratory semi-industrial direct current electric arc furnace is rotated to a certain degree, asbestos used for heat insulation and heat preservation is taken out of the position, located in the hearth 102, beside the crucible 103 with extremely high temperature, then the threaded bayonet on the crucible water-cooling spiral pipe 332 is connected with the crucible water-cooling water supply pipe 333 and the crucible water-cooling water return pipe 334, then the crucible water-cooling spiral pipe 332 is sleeved on the crucible 103, the crucible water-cooling water supply control valve 336 is rapidly opened, the crucible water-cooling water supply pump 335 is started, and the link of rapid water cooling of the partition wall of the high-temperature graphite crucible 103 is carried out. Meanwhile, the air cooling fan 31 is rotated by a certain angle, so that the air cooling fan 31 faces the crucible 103 in the hearth, and the surrounding air is driven to perform forced natural convection heat transfer to take away the heat of the high-temperature graphite crucible 103.

Because there is no high-temperature flue gas and heat input from the transformer 105 side, the temperature of the heat-conducting oil will gradually decrease, and the power generation amount by thermoelectric power generation will also decrease. Phase change material that originally fully stored energy plays key role this moment, in case the temperature of conduction oil is less than phase change material's phase transition temperature point, the phase change material that the smelting stage was heated and is melted just can progressively release the heat of storage, change into solid-state from the liquid, this part heat just can transmit the conduction oil, continue to maintain the temperature of the conduction oil of a period, thereby make the difference in temperature of semiconductor thermoelectric generation not receive too big influence, keep certain generated energy, continue the operation of drive water pump and fan, thereby the high-efficient quick heat of taking away graphite crucible 103 surface, shorten the smelting time, prevent the oxidation of material and the destruction of crystalline phase in the crucible 103.

When the temperature of the crucible 103 is lowered to a level where the crucible can be taken out, the whole apparatus can be turned off again to wait for the next experiment, and the related procedures are continued to be circulated as described above.

It should be noted that automatic control systems may be introduced with respect to the related valves and the start-up and shut-down or operation of the water pumps, oil pumps, fans, etc., and these types of automatic control systems are now well-established and may be fully utilized in the apparatus of the present invention.

The heat recovery crucible cooling system for electric arc furnace steelmaking of the invention utilizes high-temperature phase-change materials and heat pipes to store and transmit waste heat from a transformer and a flue, utilizes semiconductor temperature difference power generation to utilize the part of heat, achieves the purposes of quenching the crucible by subsequent water cooling and air cooling and preventing materials from being oxidized, and is mainly based on the following principle:

(1) heat recovery principle of phase change material. The phase-change material absorbs external heat or releases heat to the external environment mainly through the transformation of the phase state of the phase-change material, so that the energy is collected and released. The phase change material is used for waste heat recovery, can store a plurality of waste heat and generate beneficial effects by utilizing the waste heat. When the temperature of the external environment is higher than the melting point temperature of the phase-change material, the phase-change material absorbs heat from the external high-temperature environment, and simultaneously gradually converts the phase-change material from a solid state to a liquid state to store a large amount of heat. When the temperature of the external environment is gradually reduced and is lower than the melting point temperature of the phase-change material, the phase-change material releases heat to the external environment, and simultaneously gradually converts the phase-change material from a liquid state to a solid state to release a large amount of heat.

In the smelting process of the electric arc furnace, the waste heat of high-temperature flue gas generated by components such as a transformer 105 and the like and a flue 100 in the steelmaking process of the semi-industrial electric arc furnace in a laboratory can be effectively recovered by utilizing the heat storage capacity of the phase-change material in the phase-change process, and the waste heat is stored in the smelting process. After smelting is finished, the part of heat stored by the phase-change material can be used as a heat supply end of subsequent semiconductor thermoelectric power generation to drive a subsequent quenching crucible for rapid cooling.

(2) The heat pipe is based on the principle of high-efficiency heat transfer. The heat pipe is a special material with the characteristic of rapid temperature equalization, the hollow metal pipe body has the characteristic of light weight, and the characteristic of rapid temperature equalization enables the heat pipe to have excellent heat superconducting performance. The heat pipe is mainly used for transferring heat by the vapor-liquid phase change of the working liquid, and has low thermal resistance, so that the heat pipe has high heat conduction capability. Compared with metals such as silver, copper, aluminum and the like, the heat pipe with unit weight can transmit heat of several orders of magnitude more, has strong heat transfer capacity in the axial direction, and can independently change the heating area of the evaporation section or the cooling section, namely, the heat is input in a smaller heating area and output in a larger cooling area, or the heat pipe can input heat in a larger heat transfer area and output heat in a smaller cooling area, so that the heat flow density can be changed. After the hot end of the heat pipe is heated, the liquid inside the heat pipe absorbs heat and evaporates, and after the cold end of the heat pipe is encountered, the liquid is liquefied to release the heat carried by the liquid, and meanwhile, the liquid flows back to the hot end of the heat pipe along the inner pipe wall to carry out next circulation, so that the high-speed effective heat transfer is realized by means of the phase change of the internal fluid.

(3) Semiconductor thermoelectric generation and temperature measurement. The seebeck effect, also called the first thermoelectric effect, is a thermoelectric phenomenon in which a voltage difference between two substances is caused by a temperature difference between two different electrical conductors or semiconductors. In a circuit composed of two metals a and B, if the temperatures of the two contact points are made different, a current, called a thermal current, will appear in the circuit. The essence of the seebeck effect is that when two metals are in contact, a contact potential difference is generated, and the potential difference depends on two basic factors, namely the electron work function and the effective electron density of the metals.

The semiconductor has large temperature difference electromotive force and can be used as a temperature difference generator. The concentration of the hot end holes of the P-type semiconductor 24 is high, the holes diffuse from the high temperature end to the low temperature end, under the condition of the passage, space charges (negative charges at the hot end and positive charges at the cold end) are formed at the two ends of the P-type semiconductor 24, an electric field appears in the semiconductor, when the diffusion effect and the drift effect of the electric field are mutually offset, a stable state is reached, and electromotive force, namely temperature difference electromotive force, caused by temperature gradient appears at the two ends of the semiconductor. The direction of the thermoelectromotive force of the P-type semiconductor 24 is from a low-temperature end to a high-temperature end (the Seebeck coefficient is negative), and conversely, the direction of the thermoelectromotive force of the N-type semiconductor 23 is from a high-temperature end to a low-temperature end (the Seebeck coefficient is positive), so that an electric field exists in a semiconductor with temperature difference, generally, the Seebeck coefficient of the semiconductor is hundreds of mV/K, and therefore, in the occasion with large temperature difference, the thermoelectric generation capacity of the semiconductor is still considerable, and the purpose of driving a fan and a water pump can be completely met, and the purpose of cooling the crucible 103 after smelting is achieved.

When the temperature of the electric arc furnace flue 100, the hot oil at the side of the transformer 105 and the like is measured in a feedback mode, the external standard thermocouple is not beneficial to operation and is troublesome to move back and forth, meanwhile, the external thermocouple is high in consumption, the temperature is high after the external standard thermocouple is heated, and potential safety hazards exist. The metal Seebeck effect is very small, the Seebeck coefficient is 0-10 mV/K generally, but the metal Seebeck effect is still considerable under certain conditions, and the metal Seebeck effect is completely feasible for detecting the temperature in high-temperature occasions. If the mean free path of the hot-end electrons is increased along with the increase of the energy of the electrons, the electrons at the hot end have larger energy and larger mean free path, the transportation of the hot-end electrons to the cold end is a main process, and thus the seebeck effect with negative seebeck coefficient, such as metal Al, Mg, Pd, Pt and the like, is generated. On the contrary, if the mean free path of the electrons at the hot end decreases with the increase of the energy of the electrons, the electrons at the hot end have a smaller mean free path although having a larger energy, and therefore the transport of the electrons will be mainly from the cold end to the hot end, and thus the seebeck effect with a positive seebeck coefficient, such as metal Cu, Au, Li, etc., will be generated. The temperature from-180 ℃ to +2000 ℃ can be easily measured by only selecting proper metal as the temperature measuring material. Therefore, the control on the flue gas temperature of the flue 100, the local temperature of the transformer 105 and the like can be realized through the metal Seebeck effect, the local area is prevented from being damaged by overheating, and corresponding regulation and control can be timely performed.

(4) The dividing wall water cooling and forced convection are combined to reduce the temperature. The cooling of the crucible 103 in the semi-industrial direct current arc furnace smelting process at the present stage still belongs to natural cooling. Through the semiconductor temperature difference power generation technology of the device, the stored electric quantity can drive the fan and the water pump to operate, and efficient heat transmission and rapid quenching are carried out. The whole device can run by waste heat without an external heat source.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides an electric arc furnace is heat recovery crucible cooling system for steelmaking which characterized in that includes:

the device comprises a flue gas heat exchange device (1), wherein the flue gas heat exchange device (1) is connected with a flue (100) and a dust collection cover (101) of the electric arc furnace so as to recover heat in high-temperature flue gas;

the high-temperature side of the semiconductor temperature difference power generation device (2) is connected with the flue gas heat exchange device (1) so as to utilize the heat recovered by the flue gas heat exchange device (1) to perform temperature difference power generation;

the semiconductor temperature difference power generation device (2) is connected with the crucible cooling device (3) and supplies power to the crucible cooling device (3);

the flue gas heat exchange device (1) comprises:

the device comprises a flue gas side heat conduction oil pool (11), wherein a flue gas side heat conduction oil pool high-temperature heat pipe (15) is connected to the flue gas side heat conduction oil pool (11), and the other end of the flue gas side heat conduction oil pool high-temperature heat pipe (15) is connected with the high-temperature side of the semiconductor temperature difference power generation device (2);

the flue gas heat exchange tube (12) is arranged in the flue (100) and the dust collection cover (101), a flue gas heat exchange tube heat conduction oil inlet is formed in the upper end of the flue (100) of the flue gas heat exchange tube (12), and a flue gas heat exchange tube heat conduction oil outlet is formed in the lower end of the dust collection cover (101) of the flue gas heat exchange tube (12);

a flue gas side heat conduction oil pool heat conduction oil outlet pipeline (13), wherein one end of the flue gas side heat conduction oil pool heat conduction oil outlet pipeline (13) is connected with the flue gas side heat conduction oil pool (11), the other end of the flue gas side heat conduction oil pool heat conduction oil outlet pipeline (13) is connected with a flue gas heat exchange pipe heat conduction oil inlet, and a flue gas side heat conduction oil pump (16) is installed on the flue gas side heat conduction oil pool heat conduction oil outlet pipeline (13);

the heat conduction oil inlet pipeline (14) of the smoke side heat conduction oil pool is characterized in that one end of the heat conduction oil inlet pipeline (14) of the smoke side heat conduction oil pool is connected with the smoke side heat conduction oil pool (11), and the other end of the heat conduction oil inlet pipeline (14) of the smoke side heat conduction oil pool is connected with a heat conduction oil outlet of a smoke heat exchange tube.

2. The heat recovery crucible cooling system for electric arc furnace steelmaking of claim 1, wherein the flue gas heat exchange tube (12) comprises:

the flue gas heat exchange inner pipe (121), the flue gas heat exchange inner pipe (121) is filled with a phase change heat absorbing material;

the flue gas heat exchange outer pipe (122) is sleeved outside the flue gas heat exchange inner pipe (121), flue gas side heat conduction oil channels (124) through which heat conduction oil flows are formed between the flue gas heat exchange outer pipe (122) and the flue gas heat exchange inner pipe (121) at intervals, one end of the flue gas heat exchange outer pipe (122) is connected with the flue gas side heat conduction oil pool heat conduction oil outlet pipeline (13), and the other end of the flue gas heat exchange outer pipe is connected with the flue gas side heat conduction oil pool heat conduction oil outlet pipeline (14);

and the flue gas side interlayer high-temperature heat pipe (123) is arranged in the flue gas side heat conduction oil channel (124), and the flue gas side interlayer high-temperature heat pipe (123) extends out of the flue gas heat exchange outer pipe (122) and is connected with the high-temperature side of the semiconductor temperature difference power generation device (2).

3. The heat recovery crucible cooling system for electric arc furnace steelmaking according to claim 1, wherein a flue gas side heat conduction oil bath metal seebeck effect temperature measurement tube (17) is further connected to the flue gas side heat conduction oil bath (11), and the other end of the flue gas side heat conduction oil bath metal seebeck effect temperature measurement tube (17) is connected to the high temperature side of the semiconductor thermoelectric power generation device (2); a smoke metal Seebeck effect temperature measuring tube (18) is further arranged in the dust hood (101), and the other end of the smoke metal Seebeck effect temperature measuring tube (18) is connected with the high-temperature side of the semiconductor temperature difference power generation device (2).

4. The heat recovery crucible cooling system for electric arc furnace steelmaking according to claim 1, wherein the flue gas heat exchange tube conduction oil inlet and the flue gas heat exchange tube conduction oil outlet of the flue gas heat exchange tube (12) are detachably connected with the flue gas side conduction oil pool conduction oil outlet pipe (13) and the flue gas side conduction oil pool conduction oil inlet pipe (14) through a three-way pipe (19), respectively.

5. The heat recovery crucible cooling system for electric arc furnace steelmaking according to claim 1, wherein the crucible cooling device (3) comprises:

the semiconductor thermoelectric generation device comprises an air cooling fan (31), wherein the air cooling fan (31) is connected with the semiconductor thermoelectric generation device (2), and the air cooling fan (31) is rotatably arranged on a hearth (102) of the electric arc furnace through a rotating mechanism (32).

6. The heat recovery crucible cooling system for electric arc furnace steelmaking according to claim 5, wherein the crucible cooling device (3) further comprises:

crucible water cooling plant (33), crucible water cooling plant (33) includes a closed circulation water tank (331) and a crucible water-cooling spiral pipe (332), closed circulation water tank (331) through a crucible water-cooling delivery pipe (333) and a crucible water-cooling wet return (334) respectively with the both ends of crucible water-cooling spiral pipe (332) are connected, crucible water-cooling spiral pipe (332) cover is established on crucible (103) of electric arc furnace, be equipped with a crucible water-cooling feed pump (335) on crucible water-cooling delivery pipe (333).

7. The heat recovery crucible cooling system for electric arc furnace steelmaking of claim 1, further comprising a transformer heat exchanger (4), said transformer heat exchanger (4) comprising:

the semiconductor thermoelectric power generation device comprises a transformer side heat conduction oil pool (41), wherein a transformer side heat conduction oil pool high-temperature heat pipe (46) is connected to the transformer side heat conduction oil pool (41), and the other end of the transformer side heat conduction oil pool high-temperature heat pipe (46) is connected with the high-temperature side of the semiconductor thermoelectric power generation device (2);

a transformer-side spiral heat exchange tube (42), the transformer-side spiral heat exchange tube (42) being installed within a transformer rectifier cover (104) of an electric arc furnace to recover heat of a transformer (105);

a transformer side hot oil conducting and returning pipeline (43), wherein one end of the transformer side hot oil conducting and returning pipeline (43) is connected with the transformer side heat conducting oil pool (41), the other end of the transformer side hot oil conducting and returning pipeline is connected with an oil outlet of the transformer side spiral heat exchange pipe (42), and a transformer side hot oil conducting pump (47) and a multi-point balance heat exchange water cooling protector (48) are installed on the transformer side hot oil conducting and returning pipeline (43);

the oil outlet pipeline (44) is arranged on the side of the transformer, one end of the oil outlet pipeline (44) is connected with the heat conducting oil pool (41) on the side of the transformer, and the other end of the oil outlet pipeline is connected with an oil inlet of the spiral heat exchange pipe (42) on the side of the transformer;

the semiconductor thermoelectric power generation device comprises a transformer side heat conduction oil pool metal Seebeck effect temperature measurement pipe (45), wherein one end of the transformer side heat conduction oil pool metal Seebeck effect temperature measurement pipe (45) extends into the transformer side heat conduction oil pool (41), and the other end of the transformer side heat conduction oil pool metal Seebeck effect temperature measurement pipe is connected with the high-temperature side of the semiconductor thermoelectric power generation device (2).

8. The heat recovery crucible cooling system for electric arc furnace steelmaking of claim 7, wherein the transformer side spiral heat exchange tube (42) comprises:

the heat exchanger comprises a transformer side heat exchange inner tube (421), wherein a phase change heat absorption material is filled in the transformer side heat exchange inner tube (421);

transformer side heat transfer outer tube (422), the cover is established the outside of transformer side heat transfer inner tube (421), transformer side heat transfer outer tube (422) with alternate interval forms transformer side heat transfer oil passageway (423) that supplies the conduction oil to flow through between transformer side heat transfer inner tube (421), the one end of transformer side heat transfer outer tube (422) with transformer side heat transfer oil return line (43) are connected, the other end with transformer side heat transfer oil outlet line (44) are connected.

9. The heat recovery crucible cooling system for electric arc furnace steelmaking according to claim 7, wherein the transformer heat exchanging means (4) includes a plurality of the transformer-side spiral heat exchanging pipes (42), and the plurality of the transformer-side spiral heat exchanging pipes (42) are detachably connected in series.

10. The heat recovery crucible cooling system for electric arc furnace steelmaking according to any one of claims 1 to 9, wherein the semiconductor thermoelectric power generation device (2) comprises a high temperature side heat conducting ceramic (21), a high temperature side metal plate (22), an N-type semiconductor (23), a P-type semiconductor (24), a low temperature side metal plate (25), a low temperature side heat conducting ceramic (26) and an energy storage power supply (27), the high temperature side heat conducting ceramic (21) is a high temperature side of the semiconductor thermoelectric power generation device (2), the high temperature side heat conducting ceramic (21) is connected with the high temperature side metal plate (22), the N-type semiconductor (23) and the P-type semiconductor (24) are both connected with the high temperature side metal plate (22), and the other ends of the N-type semiconductor (23) and the P-type semiconductor (24) are respectively connected with one low temperature side metal plate (25), the two low-temperature side metal plates (25) are connected with the low-temperature side heat conducting ceramic (26), and the two low-temperature side metal plates (25) are respectively connected with the energy storage power supply (27) through a conducting wire.

11. The heat recovery crucible cooling system for electric arc furnace steelmaking according to claim 10, wherein one said high temperature side metal plate (22), one said N-type semiconductor (23), one said P-type semiconductor (24) and two said low temperature side metal plates (25) together constitute one semiconductor thermoelectric power generation unit, and said semiconductor thermoelectric power generation device (2) includes a plurality of said semiconductor thermoelectric power generation units, and a plurality of said semiconductor thermoelectric power generation units are connected in series.