阅读说明：本技术 一种利用液态钢渣生产钢渣粉末的装置及方法 (Device and method for producing steel slag powder by using liquid steel slag ) 是由 李志远 郁国忠 于 2020-06-01 设计创作，主要内容包括：本发明公开了一种利用液态钢渣生产钢渣粉末的装置,涉及液态钢渣处理技术及设备相关领域,包括渣池补热炉,所述的渣池补热炉右侧连接有中间罐,中间罐的底部连接有雾化装置；所述的渣池补热炉包括炉体内壳和炉体外壳,所述的炉体内壳设于炉体外壳的内部,两者间形成中空的夹套,所述的渣池补热炉顶部从左至右依次还设有主燃烧喷嘴、压缩空气入口、钢渣入口、辅燃烧喷嘴、氧化物投料口和烟气出口；底部从左至右依次还设有排铁口、电磁铁和压缩空气出口；所述的中间罐内还设有塞棒,所述的塞棒可在中间罐内上下移动。本发明装置的构造合理,设备占地少,投资少,清洁无污染,又易于热量的回收。(The invention discloses a device for producing steel slag powder by using liquid steel slag, which relates to the related field of liquid steel slag processing technology and equipment, and comprises a slag pool concurrent heating furnace, wherein the right side of the slag pool concurrent heating furnace is connected with a tundish, and the bottom of the tundish is connected with an atomizing device; the slag bath concurrent heating furnace comprises a furnace body inner shell and a furnace body outer shell, wherein the furnace body inner shell is arranged inside the furnace body outer shell, a hollow jacket is formed between the furnace body inner shell and the furnace body outer shell, and a main combustion nozzle, a compressed air inlet, a steel slag inlet, an auxiliary combustion nozzle, an oxide feed opening and a flue gas outlet are sequentially arranged at the top of the slag bath concurrent heating furnace from left to right; the bottom is sequentially provided with an iron discharging port, an electromagnet and a compressed air outlet from left to right; the middle tank is also internally provided with a stopper rod which can move up and down in the middle tank. The device has the advantages of reasonable structure, small occupied area of equipment, low investment, cleanness, no pollution and easy heat recovery.)

1. A device for producing steel slag powder by using liquid steel slag comprises a slag pool concurrent heating furnace (1), and is characterized in that the right side of the slag pool concurrent heating furnace (1) is connected with an intermediate tank (2), and the bottom of the intermediate tank (2) is connected with an atomizing device (5); the slag bath concurrent heating furnace (1) comprises a furnace body inner shell (17) and a furnace body outer shell (18), wherein the furnace body inner shell (17) is arranged inside the furnace body outer shell (18), a hollow jacket is formed between the furnace body inner shell and the furnace body outer shell, and the top of the slag bath concurrent heating furnace (1) is sequentially provided with a main combustion nozzle (7), a compressed air inlet (8), a steel slag inlet (9), an auxiliary combustion nozzle (10), an oxide feeding port (11) and a flue gas outlet (12) from left to right; the bottom is also provided with an iron discharging port (6), an electromagnet (15) and a compressed air outlet (16) from left to right in sequence; a stopper rod (3) is also arranged in the intermediate tank (2), and the stopper rod (3) can move up and down in the intermediate tank (2); the atomizing device (5) comprises a nozzle body (22), a liquid inlet nozzle (4), a primary air inlet (19), a secondary air inlet (20) and a tertiary air inlet (21).

2. The device for producing steel slag powder by using liquid steel slag according to claim 1, wherein the inner part of the furnace body inner shell (17) is a slag bath (14), a partition wall (13) is further arranged in the slag bath (14), and the partition wall (13) is arranged on the top wall of the right side of the furnace body inner shell (17); the electromagnet (15) is arranged at the bottom of the furnace body shell (18).

3. The device for producing steel slag powder by using liquid steel slag according to claim 2, wherein the outer ports of the iron discharging port (6), the main combustion nozzle (7), the steel slag inlet (9), the auxiliary combustion nozzle (10), the oxide feeding port (11) and the flue gas outlet (12) extend out of the furnace body outer shell (18), and the inner ports extend into the furnace body inner shell (17), so that the communication between the slag bath (14) and the outside of the slag bath heat supplementing furnace (1) is realized.

4. The device for producing steel slag powder by using liquid steel slag according to claim 3, wherein the external ports of the compressed air inlet (8) and the compressed air outlet (16) extend out of the furnace body outer shell (18), and the internal ports extend into the jackets in the furnace body outer shell (18) and the furnace body inner shell (17), so that the jackets are communicated with the outside of the slag bath reheating furnace (1).

5. The apparatus for producing steel slag powder from liquid steel slag according to claim 4, wherein the stopper rod (3) is vertically disposed at the center of the interior of the tundish (2), the slag bath (14) is communicated with the interior of the tundish (2), and the stopper rod (3) can control the communication or isolation between the interior of the tundish (2) and the interior of the atomizing device (5) by changing its up-down position.

6. The apparatus for producing steel slag powder from liquid steel slag according to claim 5, wherein the liquid inlet nozzle (4) is disposed between the tundish (2) and the nozzle body (22) and is an annular space jet nozzle formed between the outlet pipe of the tundish (2) and the nozzle body (22); the outer part of the nozzle body (22) is a nozzle body shell (29), the inner part of the nozzle body is a nozzle body inner cavity, a nozzle body internal part (24) is arranged in the nozzle body inner cavity, the inner part of the nozzle body internal part (24) is a cavity, the cavity sequentially consists of a premixing section (23), a contraction section (25), a throat section (26) and an expansion section (30) from left to right, and the throat section (26) is also provided with an annular gap nozzle (31); a spray head (27) is further arranged at the outlet end of the right side of the nozzle body (22), and a plurality of spray nozzles (28) are further arranged on the spray head (27); the top end part of the nozzle body internal part (24) is communicated with the primary air inlet (19), and the left side surface is communicated with the secondary air inlet (20); an annular pressure equalizing chamber (32) is formed among the nozzle body internal part (24), the nozzle body outer shell (29) and the spray head (27), and the annular pressure equalizing chamber (32) is communicated with the tertiary air inlet (21) and is also communicated with the throat section (26) of the nozzle body internal part (24) through an annular gap spray opening (31).

7. An apparatus for producing steel slag powder using liquid steel slag according to claim 6, wherein the primary air inlet (19), the secondary air inlet (20) and the tertiary air inlet (21) are connected to the compressed air outlet (16) through valves.

8. A method for producing steel slag powder by using liquid steel slag is characterized by comprising the following steps:

s1, pouring steel slag from a steel slag inlet (9) of a slag pool concurrent heating furnace (1) into a slag pool (14), then controlling combustion-supporting gas to be preheated by an air heat exchanger, mixing the combustion-supporting gas and fuel gas into a main combustion nozzle (7) for combustion, conducting combustion heat to slag liquid through radiation and convection, discharging flue gas generated in the process through a flue gas outlet (12), and controlling gas combustion in an auxiliary combustion nozzle (10) to ensure that the slag liquid keeps a certain superheat degree;

s2, adding oxides into the slag pool (14) from the oxide feeding port (11), and after the oxides react with the steel slag, the iron liquid contained in the slag liquid sinks into the bottom of the slag pool (14) under the action of gravity and the magnetic force generated by the electromagnet (15) and is periodically discharged from the iron discharging port (6);

s3, enabling the overheated slag liquid to rise to an overflow port through the bottom of a partition wall (13) and then flow into a tundish (2), controlling compressed air to be injected into a jacket through a compressed air inlet (8) during the process, discharging the preheated compressed air from a compressed air outlet (16), and shunting the preheated air to enter a primary air inlet (19), a secondary air inlet (20) and a tertiary air inlet (21) through a control valve;

s4, the stopper rod (3) in the intermediate tank (2) is vertically lifted, at the moment, slag liquid flows into the liquid inlet nozzle (4) from the outlet pipe of the intermediate tank (2), at the moment, gas in the primary air inlet (19) impacts and crushes the slag liquid for one time, then the slag liquid falls into the premixing section (23) of the nozzle body internal part (24), at the moment, gas in the secondary air inlet (20) impacts and crushes the slag liquid for two times again, then the slag liquid moves to the throat section (26), at the moment, gas in the tertiary air inlet (21) impacts and crushes the slag liquid for three times through the annular gap nozzle (31), the slag liquid accelerated and pressurized by the three times of impacts enters the nozzle (27) through the expansion section (30), and is finally sprayed out through the nozzle (28) on the nozzle (27), and the gas-liquid expansion and acceleration are realized due to sudden decompression after the spraying, and the liquid drops are crushed to form finer liquid drops, the cooled air is instantly cooled and solidified, enters the heating surface of the boiler along with the cooling air to be cooled to 150 ℃ after heat exchange, and finally enters a dust collector to achieve the effect of gas-solid separation, thereby completing the production of the steel slag powder.

9. The method of claim 8, wherein the oxide in step S2 is at least one of silica, alumina, and industrial waste containing silicon-aluminum oxide.

Technical Field

The invention relates to the field of liquid steel slag treatment technology and equipment, in particular to a device and a method for producing steel slag powder by using liquid steel slag.

Background

The research on the utilization technology of the steel slag can develop the comprehensive utilization way of the steel slag, improve the comprehensive utilization rate of the steel slag, effectively reduce the discharge and the stacking of the steel slag and ensure that the large amount of solid waste achieves the purposes of reduction, reclamation and harmlessness.

The comprehensive utilization technology of steel slag mainly comprises a pretreatment technology of high-temperature liquid steel slag, a deep processing technology of normal-temperature steel slag and a utilization technology of tailings. The comprehensive utilization of the steel slag firstly solves the problems of granulation or pulverization of the high-temperature liquid steel slag, digestion of free calcium oxide, high-efficiency separation of slag and iron, maintenance of the activity of the steel slag, and recycling of heat of the high-temperature liquid steel slag while meeting various requirements of comprehensive utilization.

At present, the domestic steel slag treatment process is mainly divided into the following types: the first is that liquid steel slag is cooled for a period of time to reach a quenchable temperature, and then water is sprayed to generate a physical and mechanical effect, so that free calcium oxide is dissolved and slag blocks are cracked; the slag is crushed, sieved and magnetically separated when cooled to normal temperature, and the disc splashing method, the hot splashing method and the hot stuffiness method belong to the category. Their disadvantages are non-uniform particle size, large subsequent crushing processing amount, large dust, complex process, long treatment period, high operation and investment costs and poor stability of steel slag. The second type is that the high-temperature liquid slag is divided and crushed by high-pressure water in the flowing and descending processes; and the high-temperature slag is quenched and shrunk in water to generate stress concentration and fracture, and is quenched and granulated at the same time. Among them, there are tilting tank water quenching, open-pore slag tank water quenching, roller water quenching and granulation wheel water quenching. The defects that the operation is improper or the slag liquid is sticky and accumulated, the explosion is easy to occur, the granularity uniformity of the steel slag is poor, and only liquid slag with good fluidity can be processed; the steel slag processed by the roller and granulation wheel method has the advantages of compact crystallization, difficult grinding, poor gelation activity, large equipment abrasion, high failure rate, short service life and large investment. The third type is a wind quenching method, which uses high-speed airflow to smash liquid steel slag stream falling in the air into fine liquid drops, and the fine liquid drops fly directionally along with the gas, and are rapidly cooled into semi-solid slag particles in the flying process, and then the semi-solid slag particles are dispersed and fall into water for rapid cooling. The air quenching method can only treat liquid slag.

The three steel slag treatment processes except the air quenching method have the defects of large steel slag lumpiness, uneven granularity and poor grindability after treatment; poor stability and low gelling activity; crushing, sorting, magnetic separation or grinding are needed in the later period; the process is complex, the investment is large, the abrasion is serious, and the energy consumption is high; only the thin slag with good fluidity can be processed, and the high-temperature liquid slag has 1600 ℃ high-temperature heat which is not recovered, so that a large amount of water is consumed for cooling.

The patent of application publication No. CN101993964A invention (metallurgical slag dry granulation and heat energy recovery) discloses that liquid slag is subjected to dry granulation by adopting a centrifugal rotating disc and an air flow pulse mode, the slag is cooled and solidified after being subjected to heat exchange with a water-cooled wall and fluidizing gas, and the heat of the slag is fully recovered while granulated slag with high vitrification rate is formed; the patent of application publication No. CN101691620A invention discloses a liquid steel slag treatment process and device, wherein gas jet flow provided by a gas quenching gas nozzle is used for crushing and granulating into liquid slag drops, and the liquid slag drops are rapidly cooled under the action of inert cooling gas of countercurrent heat exchange in the flight process to obtain high-temperature solid slag; and after the high-temperature solid slag and the cooling gas perform countercurrent heat exchange, discharging low-temperature slag particles. The high-temperature cooling gas subjected to heat exchange and temperature rise enters a waste heat boiler to recover steam after being dedusted by a gravity deduster.

In both patents, the heat of liquid slag is recovered by fluidized bed or moving bed heat exchange, and cooling gas and molten slag are used for countercurrent heat exchange. However, the heat utilization is too low, the temperature of the gas entering the boiler after heat exchange with the slag is only 450-550 ℃, and the temperature of the gas leaving the boiler is 150-200 ℃. The reason that the heat utilization is too low is that the steel slag after centrifugal granulation and air quenching granulation does not reach small enough granularity, only a fluidized bed or a moving bed is forced to be adopted, the contact time of the slag and the air is too short, the slag particles are not enough to stay in heat exchange air, and the slag particles flow through the heating surface of the boiler together to exchange heat with the heating surface.

Therefore, a device and a method for producing steel slag powder by using liquid steel slag are provided.

Disclosure of Invention

The invention aims to provide a device and a method for producing steel slag powder by using liquid steel slag, which aim to solve the problems in the background technology.

In order to achieve the purpose, the invention adopts the following technical scheme:

a device for producing steel slag powder by using liquid steel slag comprises a slag pool concurrent heating furnace, wherein the right side of the slag pool concurrent heating furnace is connected with a tundish, and the bottom of the tundish is connected with an atomizing device; the slag bath concurrent heating furnace comprises a furnace body inner shell and a furnace body outer shell, wherein the furnace body inner shell is arranged inside the furnace body outer shell, a hollow jacket is formed between the furnace body inner shell and the furnace body outer shell, and a main combustion nozzle, a compressed air inlet, a steel slag inlet, an auxiliary combustion nozzle, an oxide feed opening and a flue gas outlet are sequentially arranged at the top of the slag bath concurrent heating furnace from left to right; the bottom is sequentially provided with an iron discharging port, an electromagnet and a compressed air outlet from left to right; a stopper rod is also arranged in the intermediate tank and can move up and down in the intermediate tank; the atomization device comprises a nozzle body, a liquid inlet nozzle, a primary air inlet, a secondary air inlet and a tertiary air inlet.

Furthermore, a slag pool is arranged inside the furnace body inner shell, a partition wall is also arranged in the slag pool, and the partition wall is arranged on the top wall of the right side of the furnace body inner shell; the electromagnet is arranged at the bottom of the furnace body shell.

Furthermore, the outer ports of the iron discharging port, the main combustion nozzle, the steel slag inlet, the auxiliary combustion nozzle, the oxide feeding port and the smoke outlet extend out of the furnace body outer shell, and the inner ports extend into the furnace body inner shell, so that the external communication of the slag bath and the slag bath concurrent heating furnace is realized.

Furthermore, the outer ports of the compressed air inlet and the compressed air outlet extend out of the furnace body outer shell, the inner ports extend into the jacket in the furnace body outer shell and the furnace body inner shell, and the communication between the jacket and the outside of the slag pool concurrent heating furnace is realized.

Furthermore, the stopper rod is vertically arranged at the center of the inner part of the intermediate tank, the slag pool is communicated with the inner part of the intermediate tank, and the communication or isolation between the inner part of the intermediate tank and the inner part of the atomization device can be controlled by the stopper rod through the change of the upper position and the lower position of the stopper rod.

Furthermore, the liquid inlet nozzle is arranged between the intermediate tank and the nozzle body and is an annular space jet nozzle formed by an outlet pipe of the intermediate tank and the nozzle body; the nozzle body is provided with a nozzle body shell outside and a nozzle body inner cavity inside, a nozzle body internal part is arranged in the nozzle body inner cavity, a cavity is arranged inside the nozzle body internal part, the nozzle body internal part sequentially comprises a premixing section, a contraction section, a throat section and an expansion section from left to right, and the throat section is also provided with an annular gap nozzle; the right outlet end of the nozzle body is also provided with a spray head, and the spray head is also provided with a plurality of nozzles; the top end part of the nozzle body internal part is communicated with the primary air inlet, and the left side surface of the nozzle body internal part is communicated with the secondary air inlet; an annular pressure equalizing chamber is formed among the nozzle body internal part, the nozzle body shell and the nozzle, and is communicated with the tertiary air inlet and also communicated with the throat opening section of the nozzle body internal part through an annular gap nozzle.

Furthermore, the primary air inlet, the secondary air inlet and the tertiary air inlet are communicated with the compressed air outlet through valves.

A method for producing steel slag powder by using liquid steel slag comprises the following steps:

s1, pouring steel slag from a steel slag inlet of a slag pool concurrent heating furnace into a slag pool, then controlling combustion-supporting gas to be preheated by an air heat exchanger, mixing the combustion-supporting gas and fuel gas into a main combustion nozzle for combustion, conducting combustion heat to slag liquid through radiation and convection, discharging flue gas generated in the process through a flue gas outlet, and simultaneously controlling gas combustion in an auxiliary combustion nozzle to keep a certain superheat degree of the slag liquid;

s2, adding oxides into the slag pool from the oxide feeding port, and after the oxides react with the steel slag, the iron liquid contained in the slag liquid sinks to the bottom of the slag pool under the action of gravity and the magnetic force generated by an electromagnet and is periodically discharged from the iron discharging port;

s3, enabling the overheated slag liquid to rise to an overflow port through the bottom of the partition wall and then flow into the intermediate tank, controlling compressed air to be injected into the jacket from the compressed air inlet during the process, discharging the preheated compressed air from the compressed air outlet, and shunting the air into the primary air inlet, the secondary air inlet and the tertiary air inlet through the control valve;

s4, vertically lifting a stopper rod in a tundish, enabling slag liquid to flow into a liquid inlet nozzle from an outlet pipe of the tundish, enabling gas in a primary air inlet to impact and crush the slag liquid for the first time, enabling the slag liquid to fall into a premixing section of an internal part of a nozzle body, enabling gas in a secondary air inlet to impact and crush the slag liquid for the second time, enabling the slag liquid to move to a throat section, enabling gas in a tertiary air inlet to impact and crush the slag liquid for the third time through an annular gap nozzle, enabling the slag liquid accelerated and pressurized by the third impact to enter a nozzle through an expansion section, enabling the slag liquid to be sprayed out from a nozzle on the nozzle, reducing pressure suddenly after the slag liquid is sprayed out, enabling the gas liquid to expand and accelerate, enabling the slag liquid to be cooled and solidified instantly by cooling air, enabling the slag liquid to enter a boiler heating surface along with the cooling air to exchange heat, then being cooled to 150 ℃, and finally, the effect of gas-solid separation is achieved, and the production of the steel slag powder is completed.

Further, the oxide in step S2 is at least one of silicon dioxide, aluminum oxide, and industrial waste containing silicon-aluminum oxide.

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

the device has reasonable structure, can treat the steel slag with good liquid fluidity and can also treat the steel slag with poor molten fluidity; the slag and the iron can be separated in a liquid phase, and free calcium oxide can be digested, so that the processes of crushing and sieving are omitted, and time, labor and electricity are saved; meanwhile, the characteristics of easy cutting and crushing of slag liquid into small liquid drops are fully utilized, the energy consumption of liquid phase viscosity and surface tension is reduced, and the energy consumption is far less than that of solidification, crystallization, crushing and grinding of the steel slag; the compressed air is used for repeatedly impacting and crushing slag liquid to form steel slag powder, so that the steps of crushing, sorting, magnetic separation and grinding are avoided, the whole process flow is short, the occupied area of equipment is small, the investment is low, the cleaning and pollution-free effects are realized, the heat recovery is easy, and the popularization and application values are high.

Drawings

FIG. 1 is a schematic view of the overall structure of the apparatus of the present invention;

FIG. 2 is a schematic structural view of a slag bath concurrent heating furnace in the apparatus of the present invention;

fig. 3 is a schematic structural diagram of an atomizing device in the device of the present invention.

In the figure: 1. a slag pool concurrent heating furnace; 2. an intermediate tank; 3. a stopper rod; 4. a liquid inlet nozzle; 5. an atomizing device; 6. an iron discharging port; 7. a primary combustion nozzle; 8. a compressed air inlet; 9. a steel slag inlet; 10. an auxiliary combustion nozzle; 11. an oxide feed port; 12. a flue gas outlet; 13. a partition wall; 14. a slag pool; 15. an electromagnet; 16. a compressed air outlet; 17. a furnace body inner shell; 18. a furnace body shell; 19. a primary air inlet; 20. a secondary air inlet; 21. a tertiary air inlet; 22. a mouth body; 23. a premixing section; 24. a nozzle body inner member; 25. a contraction section; 26. a throat section; 27. a spray head; 28. a spout; 29. a mouthpiece housing; 30. an expansion section; 31. an annular slot spout; 32. an annular pressure equalizing chamber.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Referring to fig. 1-3, a device for producing steel slag powder by using liquid steel slag comprises a slag pool concurrent heating furnace 1, wherein the right side of the slag pool concurrent heating furnace 1 is connected with an intermediate tank 2, and the bottom of the intermediate tank 2 is connected with an atomizing device 5; the slag bath concurrent heating furnace 1 comprises a furnace body inner shell 17 and a furnace body outer shell 18, wherein the furnace body inner shell 17 is arranged inside the furnace body outer shell 18, a hollow jacket is formed between the furnace body inner shell and the furnace body outer shell, and the top of the slag bath concurrent heating furnace 1 is sequentially provided with a main combustion nozzle 7, a compressed air inlet 8, a steel slag inlet 9, an auxiliary combustion nozzle 10, an oxide feeding port 11 and a flue gas outlet 12 from left to right; the bottom is also provided with an iron discharging port 6, an electromagnet 15 and a compressed air outlet 16 from left to right in sequence; a stopper rod 3 is also arranged in the intermediate tank 2, and the stopper rod 3 can move up and down in the intermediate tank 2; the atomization device 5 comprises a nozzle body 22, a liquid inlet nozzle 4, a primary air inlet 19, a secondary air inlet 20 and a tertiary air inlet 21.

The furnace body inner shell 17 is internally provided with a slag pool 14, a partition wall 13 is also arranged in the slag pool 14, and the partition wall 13 is arranged on the top wall of the right side of the furnace body inner shell 17; the electromagnet 15 is arranged at the bottom of the furnace body shell 18.

The outer ports of the iron discharging port 6, the main combustion nozzle 7, the steel slag inlet 9, the auxiliary combustion nozzle 10, the oxide feeding port 11 and the smoke outlet 12 extend out of the furnace body outer shell 18, and the inner ports extend into the furnace body inner shell 17, so that the external communication between the slag bath 14 and the slag bath heat supplementing furnace 1 is realized.

The outer ports of the compressed air inlet 8 and the compressed air outlet 16 extend out of the furnace body outer shell 18, the inner ports extend into the jackets in the furnace body outer shell 18 and the furnace body inner shell 17, and the communication between the jackets and the outside of the slag bath concurrent heating furnace 1 is realized.

The stopper rod 3 is vertically arranged at the center of the interior of the intermediate tank 2, the slag bath 14 is communicated with the interior of the intermediate tank 2, and the stopper rod 3 can control the communication or isolation between the interior of the intermediate tank 2 and the interior of the atomizing device 5 through the change of the upper position and the lower position of the stopper rod.

The liquid inlet nozzle 4 is arranged between the intermediate tank 2 and the nozzle body 22 and is an annular space jet nozzle formed between an outlet pipe of the intermediate tank 2 and the nozzle body 22; the outer part of the nozzle body 22 is a nozzle body shell 29, the inner part of the nozzle body is a nozzle body inner cavity, a nozzle body internal part 24 is arranged in the nozzle body inner cavity, the inner part of the nozzle body internal part 24 is a cavity, the cavity sequentially consists of a premixing section 23, a contraction section 25, a throat section 26 and an expansion section 30 from left to right, and the throat section 26 is also provided with an annular gap nozzle 31; a spray head 27 is further arranged at the outlet end of the right side of the nozzle body 22, and a plurality of spray nozzles 28 are further arranged on the spray head 27; the top end part of the nozzle body internal part 24 is communicated with the primary air inlet 19, and the left side surface is communicated with the secondary air inlet 20; an annular pressure equalizing chamber 32 is formed among the nozzle body internal part 24, the nozzle body outer shell 29 and the spray head 27, and the annular pressure equalizing chamber 32 is communicated with the tertiary air inlet 21 and is also communicated with the throat section 26 of the nozzle body internal part 24 through an annular gap spray opening 31.

The primary air inlet 19, the secondary air inlet 20 and the tertiary air inlet 21 are all communicated with the compressed air outlet 16 through valves.

A method for producing steel slag powder by using liquid steel slag comprises the following steps:

s1, pouring steel slag from the steel-making operation into a slag pool 14 from a steel slag inlet 9 of a slag pool concurrent heating furnace 1, then controlling combustion-supporting gas to be preheated by an air heat exchanger, mixing the combustion-supporting gas and fuel gas into a main combustion nozzle 7 for combustion, conducting combustion heat to slag liquid through radiation and convection, discharging flue gas generated in the process through a flue gas outlet 12, and simultaneously controlling gas combustion in an auxiliary combustion nozzle 10 to ensure that the slag liquid keeps a certain degree of superheat;

s2, adding oxides into the slag pool 14 from the oxide feeding port 11, and after the oxides react with the steel slag, the iron liquid contained in the slag liquid sinks into the bottom of the slag pool 14 under the action of gravity and the magnetic force generated by the electromagnet 15 and is periodically discharged from the iron discharging port 6;

s3, enabling the overheated slag liquid to rise to an overflow port through the bottom of the partition wall 13 and then flow into the intermediate tank 2, controlling compressed air to be injected into the jacket through the compressed air inlet 8 during the process, discharging the preheated compressed air from the compressed air outlet 16, and shunting the air into the primary air inlet 19, the secondary air inlet 20 and the tertiary air inlet 21 through control valves;

s4, the stopper rod 3 in the intermediate tank 2 is lifted vertically, at the moment, slag liquid flows into the liquid inlet nozzle 4 from the outlet pipe of the intermediate tank 2, at the moment, gas in the primary air inlet 19 impacts and crushes the slag liquid for the first time, then the slag liquid falls into the premixing section 23 of the nozzle body internal part 24, at the moment, gas in the secondary air inlet 20 impacts and crushes the slag liquid for the second time again, then the slag liquid moves to the throat section 26, at the moment, gas in the tertiary air inlet 21 impacts and crushes the slag liquid for the third time through the annular gap nozzle 31, the slag liquid accelerated and pressurized by the third impact enters the nozzle 27 through the expansion section 30, is sprayed out through the nozzle 28 on the nozzle 27, is suddenly decompressed, expands and accelerates, forms finer liquid drops after the liquid drops are crushed, is cooled and solidified instantly by cooling air, enters the boiler heating surface along with the cooling air to exchange heat, and is cooled to 150 ℃, finally, the steel slag powder enters a dust collector to achieve the effect of gas-solid separation, and the production of the steel slag powder is completed.

The oxide in the step S2 is at least one of silicon dioxide, aluminum oxide, and industrial waste containing silicon-aluminum oxide, and is used for neutralizing and digesting free calcium oxide, adjusting the overall fluidity, and promoting slag liquid to rapidly realize slag-iron separation in liquid phase in the furnace.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.