WO2019042155A1

WO2019042155A1 - Plasma heating-based temperature regulation method and device for blast furnace hot air system

Info

Publication number: WO2019042155A1
Application number: PCT/CN2018/100980
Authority: WO
Inventors: 陈义龙; 张亮; 韩旭
Original assignee: 武汉丰盈长江生态科技研究总院有限公司
Priority date: 2017-08-29
Filing date: 2018-08-17
Publication date: 2019-03-07
Also published as: CN107574273A

Abstract

A plasma heating-based temperature regulation method and device for a blast furnace hot air system. The device comprises a metal smelting blast furnace (1) and a high-temperature hot air furnace (2) matched therewith; a blast furnace coal gas outlet (1.1) of the metal smelting blast furnace (1) and a gas inlet (2.1) of the high-temperature hot air furnace (2) are connected through a blast furnace coal gas main pipe (3), and a high-temperature air outlet (2.2) of the high-temperature hot air furnace (2) and a hot air input ring pipe (1.2) of the metal smelting blast furnace (1) are connected through a hot air conveying main pipe (4). The device further comprises at least one moderator gas heating bypass pipe (5) and a plasma heater (7) matched therewith; an output end of the moderator gas heating bypass pipe (5) is connected to middle and downstream pipe sections of the hot air conveying main pipe (4). In said method, moderator gas is introduced from an input end of the moderator gas heating bypass pipe (5), so as to feed same to the middle and downstream pipe sections of the hot air conveying main pipe (4). In this process, the moderator gas is quickly heated up as needed by means of the plasma heater, so as to reduce the fluctuation amplitude of the temperature of the hot air fed into the furnace over time.

Description

Method and device for temperature regulation of blast furnace hot air system based on plasma heating

Technical field

The invention relates to the technical field of blast furnace hot air temperature regulation, in particular to a method and a device for temperature regulation of a blast furnace hot air system based on plasma heating.

Background technique

In the blast furnace ironmaking process, one of the most effective ways to save energy and reduce consumption is to increase the furnace air temperature of the blast furnace. The hot blast stove is the main process equipment for increasing the temperature of the furnace. The existing hot blast stove uses the regenerative heat exchange method to continuously supply the blast furnace high temperature air through the blast furnace gas or the high calorific value gas combustion and the air supply alternately. The basic requirement of the blast furnace for the hot blast stove is to provide stable high temperature wind. However, each hot blast stove has the process of burning heat storage and supplying air to the blast furnace. In order to obtain stable and continuous hot air in the blast furnace, the conventional design scheme is equipped for each blast furnace. When three to four hot blast stoves are alternately operated, the high hot air can be maintained to float within a certain temperature range.

When the blast furnace hot blast stove is operated, the hot air temperature will fluctuate to a certain extent. The control of the fluctuation value is mainly determined by the valve opening degree of the cold damper, because the opening degree of the valve is affected by factors such as the accuracy of the equipment itself. Large, it is easy to cause the input cold wind pressure to fluctuate greatly during the furnace changing process. Chinese patent CN206014993U discloses a cold air intelligent regulation system for blast furnace hot blast stove equipment, and a blast furnace hot blast stove optimization control system disclosed by Chinese patent CN205874470U, which utilizes an automatic control principle and uses a PLC controller to control a cold air regulating valve. The manual adjustment is more intelligent and refined. During the process of changing the furnace, the system continuously collects the change of the cold air pressure and the flow rate. Through the preparation of the program, the fluctuation of the cold air temperature and pressure during the hot air furnace change can be effectively reduced.

However, although the above-mentioned adjustment method using cold air and hot air mixing can maintain the constant hot air temperature, the addition of cold air causes the hot air temperature in the hot air duct to decrease, and the higher the supply air temperature entering the blast furnace during production, the more stable it is. The better the effect of smelting metal in the blast furnace, the way the cold air is added loses the heat value, resulting in wasted energy.

Summary of the invention

The object of the present invention is to provide a method and a device for temperature regulation of a blast furnace hot air system based on plasma heating, which can effectively regulate the temperature fluctuation of the hot air entering the smelting blast furnace.

In order to achieve the above object, the present invention provides a plasma heating-based blast furnace hot air system temperature control method, the blast furnace hot air system includes a metal smelting blast furnace, a high temperature hot blast stove, and a hot air conveying main pipe connected therebetween; The utility model relates to introducing at least one regulating gas heating bypass pipe in the middle and downstream pipe sections of the hot air conveying main pipe, and a plasma heater for rapidly heating and heating the regulating gas conveyed by the regulating gas heating bypass pipe, and the following steps are included:

1) Introducing the regulating gas from the input end of the regulating gas heating bypass pipe, and taking it out from the output end of the regulating gas heating bypass pipe, and sending it to the middle and downstream pipe sections of the hot air conveying main pipe to make the temperature in the hot air conveying main pipe fluctuate with time. Large upstream hot air mixing;

2) The plasma heater rapidly heats up the regulating gas as needed, and dynamically controls the heating power of the plasma heater and/or dynamically controls the flow rate of the regulating gas in the gas heating bypass pipe to reduce the hot air temperature of the metal smelting blast furnace with time. Volatility.

Optionally, the heating power of the plasma heater can be controlled as follows: for the upstream hot air with large temperature fluctuation (refers to the hot air in the hot air conveying main pipe before mixing), when it is at a lower temperature, the plasma heating is adjusted. The device is at a relatively large power. The lower the temperature, the higher the heating power until the ion heater reaches the maximum power. When it is at a higher temperature, the plasma heater is adjusted to be less powerful. The higher the temperature, the lower the heating power. When the upstream hot air temperature exceeds the regulation target temperature line, the power of the plasma heater is adjusted to be zero, that is, no heating.

Alternatively, the gas composition of the conditioning gas may be upstream hot air, outside air, steam, pure oxygen, or the like, or a mixed gas of two or more of them.

Preferably, the regulating gas adopts outside air, and the outside air is first subjected to pressure treatment to overcome the system resistance and adapt to the subsequent system pressure demand; then preheating to 200-800 ° C, and then heating rapidly by the plasma heater. In the low temperature stage, the conventional heating method, such as waste heat heat exchange and blast furnace gas combustion mode, has better economy; while in the high temperature stage, the plasma heater has better heating efficiency and can provide higher temperature. In conventional control methods in which a portion of the cold air is blended to lower the overall temperature of the hot air entering the metal smelting blast furnace to achieve a constant temperature, it is not practical to adjust the gas preheating. The invention adopts a plasma-blended heating gas to increase the overall temperature of the hot air entering the metal smelting blast furnace to achieve a constant temperature control mode, so adjusting the gas preheating will reduce the electric energy consumption of the plasma torch, combined with the utilization of waste heat, economy The benefits are even more significant.

Preferably, the regulating gas adopts an upstream hot air drawn from a branch line of the upstream section of the hot air conveying main pipe, which is directly heated and heated by a plasma heater.

Preferably, the mass flow rate of the conditioned gas is 5 to 30% of the upstream hot air mass flow rate in the hot air delivery main pipe. By adopting the bypass input regulating gas to regulate the hot air temperature, on the one hand, the accuracy and real-time of the hot air temperature control are improved; on the other hand, the power consumption of the plasma heater is reduced.

Preferably, the dynamic control adopts fuzzy mathematics cooperative control technology, and the hot air temperature entering the metal smelting blast furnace is constant as the first control target, and the plasma heater consumes the minimum power as the second control target to enter the hot air temperature of the metal smelting blast furnace. The maximum degree of lift is the third control target; the first control target is preferentially achieved during dynamic control, the second control target is reached second, and finally the third control target is reached.

Preferably, the following mathematical relationships are satisfied between the main control parameters of the fuzzy mathematical cooperative control technology:

Where: f is the function symbol; P is the total power of the plasma heater; T ₁ and Q ₁ are the temperature and flow rate of the plasma working gas; T ₂ and Q ₂ are the high temperature air outlet temperature and flow rate of the high temperature hot blast stove; ₃ , Q ₃ is the high temperature regulating gas temperature and flow rate after plasma heating; T ₄ and Q ₄ are the high temperature hot air temperature and flow rate of the metal smelting blast furnace inlet; C ₀ is the hot air specific heat; the unit of each physical quantity in the formula adopts the SI unit The temperature is K, the flow rate is kg/s, the power is W, and the specific heat is J·kg ^-1 ·K ^-1 .

The invention also provides a plasma heating-based blast furnace hot air system temperature control device, comprising a metal smelting blast furnace and a high-temperature hot blast stove matched thereto; the upper and lower portions of the metal smelting blast furnace are respectively provided with a blast furnace gas outlet and a hot air input ring a heating inlet passage of the high-temperature hot blast stove is provided with a gas inlet and a tail gas outlet, wherein the heat absorption passage of the high-temperature hot blast stove is provided with a normal temperature air inlet and a high temperature air outlet; the blast furnace gas outlet and the gas inlet Connected by a blast furnace gas main pipe, the high-temperature air outlet and the hot air input ring pipe are connected by a hot air conveying main pipe; and further comprising at least one regulating gas heating side pipe and a plasma heater matched therewith; the regulating gas heating The input end of the bypass pipe is connected to the external air source or to the branch pipe leading from the upstream pipe section of the hot air conveying main pipe, and the output end of the regulating gas heating bypass pipe is connected to the middle and downstream pipe sections of the hot air conveying main pipe, and the plasma heater is used for The regulating gas heated by the bypass heating pipe is heated and heated rapidly.

Preferably, the plasma heater has a central cylindrical chamber and a peripheral annular chamber which are arranged at intervals, and the central cylindrical chamber and the peripheral annular chamber are transported by at least two branches arranged radially from the inside to the outside. The pipeline is connected, and at least one plasma torch is disposed on each branch conveying pipeline; the peripheral annular air chamber is provided with a regulating gas input interface, and the central cylindrical air chamber is provided with a gas chamber end interface; The plasma heater is coupled to the conditioned gas heating bypass via a regulated gas input port and a plenum end interface. The plasma heater of this solution is suitable for installation on a regulated gas heating bypass.

Preferably, the plasma heater has a central cylindrical chamber and a peripheral annular chamber which are arranged at intervals, and the central cylindrical chamber and the peripheral annular chamber are transported by at least two branches arranged radially from the inside to the outside. The pipeline is connected, and at least one plasma torch is disposed on each branch conveying pipeline; the peripheral annular air chamber is provided with a regulating gas input interface, and the central cylindrical air chamber is provided with a pair of air chamber end interfaces; The plasma heater is connected to the hot air conveying main pipe through a pair of air chamber end interfaces, and is located at a joint of the hot air conveying main pipe and the regulating gas heating side pipe, and the regulating gas input port is connected with the output of the regulating gas heating side pipe. Connected to the end. The plasma heater of this solution is suitable for installation on a hot air delivery main.

Preferably, in the above two solutions, the angle between the branch conveying pipeline and the central cylindrical air chamber is an acute angle, and is installed in a forward flow manner to reduce the input resistance of the regulating gas. The plasma torch can also be installed in a forward flow manner, so that the working gas flow direction of the ion torch is the same as the flow direction of the regulating gas or the angle is an acute angle.

Preferably, the input end of the regulating gas heating bypass pipe is provided with a pressure fan, and the regulating gas heating bypass pipe between the pressure fan and the plasma heater is provided with a preheating device.

The beneficial effects of the present invention are as follows:

1) The invention adopts an additional regulating gas heating bypass pipe and a plasma heater, utilizes plasma heating temperature high, and can quickly realize load regulation through current regulation control, introduces a control gas with controllable temperature flow, and adjusts hot air temperature in real time. When the original hot air temperature is at a lower temperature, the heat input by the plasma heater is increased; when the original hot air temperature is at a higher temperature, the heat input by the plasma heater is lowered (if necessary, the plasma heating is stopped), thereby making the metal The fluctuation of the hot air temperature in the smelting blast furnace is greatly reduced, and the overall temperature is improved.

2) Different from the conventional blending part of the cold air to lower the overall temperature of the hot air entering the metal smelting blast furnace to achieve a constant temperature control mode, the present invention uses a part of the high temperature regulating gas heated by the plasma to increase the overall temperature of the hot air entering the blast furnace. In order to achieve a constant temperature control mode, the overall temperature of the hot air entering the furnace is not lowered, and the average temperature of the hot air entering the furnace of the metal smelting blast furnace can be improved compared with the temperature regulation mode of the mixed cold air, and the utilization of waste heat is utilized, and the economic benefit is more remarkable.

3) In the heating mode above 1000 °C, the plasma torch has the highest air efficiency, lowest energy consumption, simple system and stable operation.

4) The improvement of hot air temperature and stable control can greatly improve the proportion of pulverized coal injected into the smelting blast furnace, improve the blast furnace production efficiency, reduce the coke ratio, reduce carbon emissions, and make the overall economic performance good.

5) The temperature control equipment of the blast furnace hot air system is simple and reliable, and the investment is small. The renovation project of the existing blast furnace hot air system is small and has a good investment prospect.

DRAWINGS

1 is a schematic view showing the process of the temperature control device of the blast furnace hot air system in the first embodiment.

2 and 3 are respectively a schematic view of the front view of the medium ion heater of FIG. 1 and a schematic view of the left side view; in FIG. 2, the central cylindrical gas chamber is partially cut; in FIG. 3, the central cylindrical gas is not shown. The connecting flange of the chamber.

4 is a schematic view showing the process of the temperature control device of the blast furnace hot air system in Embodiment 2.

5 and FIG. 6 are respectively a front view and a left side view of the medium ion heater of FIG. 4; in FIG. 5, a partial cut of the central cylindrical gas chamber; in FIG. 6, the central cylindrical gas is not shown. The connecting flange of the chamber.

Figure 7 is a comparison of the effects of the present invention and the method of mixing cold air.

Among them: metal smelting blast furnace 1, blast furnace gas outlet 1.1, hot air input loop 1.2, high temperature hot blast stove 2, gas inlet 2.1, high temperature air outlet 2.2, normal temperature air inlet 2.3, exhaust gas outlet 2.4, blast furnace gas main 3, hot air transport supervisor 4 , branch pipe 4.1, regulating gas heating bypass pipe 5, pressure fan 6, plasma heater 7, central cylindrical air chamber 7.1, peripheral annular air chamber 7.2, branch conveying line 7.3, plasma torch 7.4, regulating gas input interface 7.5, air chamber end interface 7.6, connecting flange 7.7, blind plate 7.8, preheating device 8, chimney 9

Detailed ways

The invention will be further described in detail below with reference to the drawings and specific embodiments.

As shown in FIGS. 1 to 6, the plasma heating-based blast furnace hot air system temperature control device designed by the present invention comprises a metal smelting blast furnace 1 and a high-temperature hot blast stove 2 matched thereto. The upper and lower portions of the metal smelting blast furnace 1 are respectively provided with a blast furnace gas outlet 1.1 and a hot air input ring pipe 1.2. The heating passage of the high temperature hot blast stove 2 is provided with a gas inlet 2.1 and an exhaust outlet 2.4. The heat absorbing passage of the high temperature hot blast stove 2 is provided with a normal temperature air inlet 2.3 and a high temperature air outlet 2.2. The blast furnace gas outlet 1.1 and the gas inlet 2.1 are connected by a blast furnace gas main pipe 3, and the high temperature air outlet 2.2 and the hot air input ring pipe 1.2 are connected by a hot air conveying main pipe 4. It also includes a regulating gas heating bypass 5 and a plasma heater 7 associated therewith. The output end of the regulating gas heating bypass pipe 5 is connected to the downstream pipe section of the hot air conveying main pipe 4, and the plasma heater 7 is used for rapidly heating and heating the regulating gas supplied from the regulating gas heating bypass pipe 5.

The process systems used in Examples 1 and 2 are slightly different and will be described separately below.

Example 1

As shown in FIGS. 1 to 3, in the present embodiment, the input end of the regulating gas heating bypass pipe 5 is provided with a pressurizing fan 6, and the regulating gas heating side pipe 5 between the pressurizing fan 6 and the plasma heater 7 is disposed. There is a preheating device 8. The plasma heater 7 has a central cylindrical plenum 7.1 and a peripheral annular plenum 7.2 arranged at intervals, and between the central cylindrical plenum 7.1 and the peripheral annular plenum 7.2, four branch conveying lines are arranged radially from the inside to the outside. Connected, a plasma torch 7.4 is disposed on each branch delivery line 7.3. The angle between the branch conveying line 7.3 and the central cylindrical chamber 7.1 is an acute angle to reduce the input resistance of the regulating gas. A peripheral air chamber 7.2 is provided with a regulating gas input port 7.5. Both ends of the central cylindrical gas chamber 7.1 are provided with a pair of connecting flanges 7.7, wherein one end of the connecting flange 7.7 serves as a gas chamber end port 7.6, and the other end The connecting flange is sealed by a blind plate 7.8. The plasma heater 7 is connected to the conditioned gas heating bypass 5 via a regulating gas input port 7.5 and a plenum end port 7.6.

Example 2

As shown in FIGS. 4-6, in another embodiment, the input end of the regulating gas heating bypass pipe 5 is connected to the branch pipe 4.1 led from the upstream pipe section of the hot air conveying main pipe 4; the original hot air introduced into the upstream pipe section is used as the regulating gas, fully The power consumption of the plasma heater 7 is reduced by the heat in the original hot air. The plasma heater 7 has a central cylindrical plenum 7.1 and a peripheral annular plenum 7.2 arranged at intervals, and between the central cylindrical plenum 7.1 and the peripheral annular plenum 7.2, four branch conveying lines are arranged radially from the inside to the outside. Connected, a plasma torch 7.4 is disposed on each branch delivery line 7.3. The angle between the branch conveying line 7.3 and the central cylindrical chamber 7.1 is an acute angle to reduce the input resistance of the regulating gas. A regulating gas input port 7.5 is disposed on the peripheral annular plenum 7.2, and a pair of connecting flanges 7.7 are disposed at both ends of the central cylindrical plenum 7.1 as a gas chamber end port 7.6. The plasma heater 7 is connected to the hot air conveying main pipe 4 through a pair of air chamber end ports 7.6, and is located at the junction of the hot air conveying main pipe 4 and the regulating gas heating bypass pipe 5, and the regulating gas input port 7.5 and the regulating gas heating side pipe 5 The outputs are connected.

In the above two embodiments, the structure of the plasma heater 7 is different: the central cylindrical chamber 7.1 of the embodiment 2 is provided with an opening at both ends; and one end of the central cylindrical chamber 7.1 of the embodiment 1 is provided as an opening, and One end is sealed by a blind plate 7.8.

The plasma heater 7 can also be arranged with a plurality of baffle or pit structure components for enhancing the heat exchange and mixing of the plasma and the high temperature working gas of the plasma torch, wherein the baffle member is made of high temperature resistant refractory insulation bricks.

The following provides a method for temperature regulation of a blast furnace hot air system using the above temperature control device.

Taking ironmaking as an example, the basic smelting process of the existing metal smelting blast furnace 1 is: iron ore, coke and other ironmaking raw materials are sent to the metal smelting blast furnace 1, and the hot air input ring pipe from the lower part of the metal smelting blast furnace 1 1.2 High-speed blasting of high-temperature hot air above 1000 °C, high-temperature hot air and coke burning and chemical conversion, iron ore is reduced by reducing gas to produce molten iron, molten iron flows out from the bottom, and blast furnace gas is smelted from the furnace of metal blast furnace 1 The top blast furnace gas outlet 1.1 is taken out, and then enters the high-temperature hot blast stove 2 through the blast furnace gas main pipe 3, the gas inlet 2.1, and heats the heat from the normal temperature air inlet 2.3 into the high-temperature hot blast stove 2 to supply the cold air, cold air. It is heated to above 1000 °C through the exhaust gas outlet 2.4, and the hot air conveying main pipe 4 is sent to the hot air input ring pipe 1.2, and the exhaust gas after the combustion of the blast furnace gas enters the outer row of the chimney 9 from the exhaust gas outlet 2.4.

Since the high temperature hot blast stove 2 uses a regenerative heat or ceramic heat exchanger, the high temperature hot air generated by the high temperature hot blast stove 2 may cause large temperature fluctuations due to the heat exchange process and the heat transfer process, which is disadvantageous to the stability and improvement of the blast furnace temperature. . In order to solve the problem, the present invention applies the blast furnace hot air system temperature control device provided in

Embodiments

1 and 2, and performs temperature regulation of the blast furnace hot air system according to the following steps:

1) Introducing the regulating gas from the input end of the regulating gas heating bypass pipe 5, and rapidly heating and heating the regulating gas by the plasma heater 7, and the plasma heater 7 is heated by the high temperature (about 5500 ° C or more) working gas generated by the plasma torch 7.4. Regulate the gas.

The total power of the plasma heater 7 is set according to the hot air conditioning load. Four Marc-11 plasma torches are used. The maximum power of a single plasma torch is 2.4 MW, the minimum power is 0.8 MW, and the plasma working gas flow rate is about 500 kg/hr.

For the first embodiment, the regulating air is made of outside air, and the outside air is first pressurized by the pressurizing fan 6 to ensure that the regulating gas can be smoothly delivered to the pressure of the blast furnace gas main pipe 3, and then preheated to about 500 ° C by the preheating device 8 . The plasma heater 7 is then used for rapid heating and temperature rise.

For the embodiment 2, the regulating gas adopts the upstream hot air drawn from the branch line 4.1 of the upstream pipe section of the hot air conveying main pipe 4, and is directly heated by the plasma heater 7 for rapid heating.

2) The obtained high-temperature regulating gas is taken out from the output end of the regulating gas heating bypass pipe 5, and sent to the middle and downstream pipe sections of the hot air conveying main pipe 4 to be mixed with the upstream hot air whose temperature in the hot air conveying main pipe 4 fluctuates greatly with time.

3) by dynamically controlling the heating power of the plasma heater 7 and/or dynamically controlling the flow rate of the regulating gas in the gas heating bypass pipe 5, increasing the hot air temperature of the metal smelting blast furnace 1 while reducing the fluctuation of the hot air temperature of the furnace into time. Amplitude.

The dynamic control adopts fuzzy mathematics cooperative control technology, and the hot air temperature entering the metal smelting blast furnace 1 is constant as the first control target, and the plasma heater 7 consumes the minimum power as the second control target to enter the hot air temperature of the metal smelting blast furnace 1 The maximum degree of lift is the third control target. In the dynamic control, the first control target is preferentially achieved, the second control target is reached secondly, and finally the third control target is reached. The following mathematical relationships are satisfied between the main control parameters:

Where f is the function symbol; P is the total power of the plasma heater 7; T ₁ and Q ₁ are the temperature and flow rate of the plasma working gas; T ₂ and Q ₂ are the high temperature air outlet temperature and flow rate of the high temperature hot blast stove 2 T ₃ and Q ₃ are the high temperature regulating gas temperature and flow rate after plasma heating; T ₄ and Q ₄ are the high temperature hot air temperature and flow rate of the metal smelting blast furnace 1 inlet; C ₀ is the hot air specific heat. The units of each physical quantity in the formula are in SI units.

In the actual control process, more reliable or accurate measured values are also involved in the process of fuzzy control based on actual flow, pressure or differential pressure. This is only a change in the form of control variables, and the main control principle does not have an essential change.

Through the above steps, high-temperature hot air with a temperature fluctuation range in an economically reasonable range is obtained, and is sent to the metal smelting blast furnace 1 for use in the iron making process.

As shown in Fig. 7, the hot air inlet temperature of the pre-regulating metal smelting blast furnace is 1000-1200 ° C, the average temperature is 1100 ° C; the average temperature after the control is increased to 1200 ° C; and the average temperature obtained by blending the cold air method is 1070 ° C. Obviously, the temperature fluctuation of the solution of the present invention is smaller, and the improvement of the hot air temperature is achieved.

From the experience of years of metal smelting blast furnace 1 production, each increase in wind temperature of 55.5 ° C can reduce the coke ratio of 12.5 kg / ton of iron, improve production efficiency of about 2.5%, while the hot air temperature increase also improves the metal smelting blast furnace 1 burner The proportion of pulverized coal reduces the internal coke consumption of the metal smelting blast furnace 1, thereby achieving a reduction in the ironmaking coke ratio. Compared with the existing method of mixing cold air, in the first and second embodiments, the hot air temperature of the metal smelting blast furnace is increased by 130 ° C, the coke ratio is reduced by 40 kg / ton of iron, and the carbon dioxide emission is reduced by 2% to 6%. Overall, it can greatly improve the operational stability and economic benefits of the ironmaking system.

Claims

A plasma heating-based blast furnace hot air system temperature control method, the blast furnace hot air system comprises a metal smelting blast furnace (1), a high temperature hot blast stove (2), and a hot air conveying main pipe (4) connected therebetween, Features are:

The method is to set at least one regulating gas heating bypass pipe (5) in the middle and downstream pipe sections of the hot air conveying main pipe (4), and a plasma heater for rapidly heating and heating the regulating gas sent by the regulating gas heating bypass pipe (5). (7) and includes the following steps:

1) Introducing the regulating gas from the input end of the regulating gas heating bypass pipe (5), and withdrawing it from the output end of the regulating gas heating bypass pipe (5), and sending it to the middle and downstream pipe sections of the hot air conveying main pipe (4) to make it The hot air conveying main pipe (4) is mixed with the upstream hot air whose temperature fluctuates greatly with time;

2) The plasma heater (7) rapidly heats the regulating gas as needed, and dynamically controls the heating power of the plasma heater (7) and/or dynamically controls the flow rate of the regulating gas in the gas heating bypass pipe (5) to reduce The fluctuation of the hot air temperature of the metal smelting blast furnace (1) with time.
The method for regulating temperature of a blast furnace hot air system based on plasma heating according to claim 1, wherein the regulating gas is external air, and the outside air is first subjected to pressure treatment, and then preheated to 200 to 800 ° C, and then passed through plasma. The heater (7) is heated for rapid heating.
The method for regulating temperature of a blast furnace hot air system based on plasma heating according to claim 1, wherein the regulating gas adopts an upstream hot air drawn from a branch line (4.1) of the upstream pipe section of the hot air conveying main pipe (4), which is directly The temperature is raised by rapid heating by the plasma heater (7).
The plasma heating-based blast furnace hot air system temperature control method according to claim 1, wherein the mass flow rate of the regulating gas is 5 to 30% of the upstream hot air mass flow rate in the hot air conveying main pipe (4).
The method for controlling temperature of a blast furnace hot air system based on plasma heating according to any one of claims 1 to 4, wherein the dynamic control adopts fuzzy mathematics cooperative control technology to enter a hot air temperature of the metal smelting blast furnace (1) Constantly as the first control target, the plasma heater (7) consumes the least power as the second control target, and enters the metal smelting blast furnace (1) to maximize the hot air temperature rise as the third control target; Control the target, secondly achieve the second control goal, and finally reach the third control target.
A plasma heating-based blast furnace hot air system temperature control device comprises a metal smelting blast furnace (1) and a high-temperature hot blast stove (2) matched thereto; the upper and lower portions of the metal smelting blast furnace (1) are respectively provided with a blast furnace gas outlet (1.1) and a hot air input ring pipe (1.2); the heating passage of the high temperature hot air furnace (2) is provided with a gas inlet (2.1) and an exhaust gas outlet (2.4), and the heat absorption passage of the high temperature hot air furnace (2) A normal temperature air inlet (2.3) and a high temperature air outlet (2.2) are disposed thereon; the blast furnace gas outlet (1.1) and the gas inlet (2.1) are connected by a blast furnace gas main pipe (3), and the high temperature air outlet ( 2.2) is connected to the hot air input ring pipe (1.2) through a hot air conveying main pipe (4), and is characterized in that:

It further comprises at least one regulating gas heating bypass pipe (5) and a plasma heater (7) associated therewith; the input end of the regulating gas heating bypass pipe (5) is connected to an external gas source or to a hot air conveying main pipe (4) a branch line (4.1) leading from the upstream pipe section is connected, an output end of the regulating gas heating bypass pipe (5) is connected to a downstream pipe section of the hot air conveying main pipe (4), and the plasma heater (7) is used for the Adjust the gas supplied by the gas heating bypass pipe (5) for rapid heating and temperature rise.
A plasma heating-based blast furnace hot air system temperature control apparatus according to claim 6, wherein said plasma heater (7) has a central cylindrical chamber (7.1) and a peripheral annular chamber (7.2) arranged at intervals The central cylindrical air chamber (7.1) and the peripheral annular air chamber (7.2) are connected by at least two branch conveying lines (7.3) radially arranged from the inside to the outside, and each branch conveying line (7.3) At least one plasma torch (7.4) is disposed on the outer annular chamber (7.2), and a regulating gas input port (7.5) is disposed on the central cylindrical chamber (7.1). Interface (7.6); the plasma heater (7) is connected to the regulated gas heating bypass (5) via a regulating gas input port (7.5) and a plenum end port (7.6).
A plasma heating-based blast furnace hot air system temperature control apparatus according to claim 6, wherein said plasma heater (7) has a central cylindrical chamber (7.1) and a peripheral annular chamber (7.2) arranged at intervals The central cylindrical air chamber (7.1) and the peripheral annular air chamber (7.2) are connected by at least two branch conveying lines (7.3) radially arranged from the inside to the outside, and each branch conveying line (7.3) At least one plasma torch (7.4) is disposed on the outer annular chamber (7.2); a regulating gas input port (7.5) is disposed on the peripheral annular gas chamber (7.2), and a pair of gas chamber ends are disposed on the central cylindrical gas chamber (7.1) Interface (7.6); the plasma heater (7) is connected to the hot air delivery main pipe (4) through a pair of air chamber end interfaces (7.6), and is located at the hot air conveying main pipe (4) and the regulating gas heating side pipe (5) At the junction, the regulating gas input port (7.5) is connected to the output end of the regulating gas heating bypass (5).
The plasma heating-based blast furnace hot air system temperature control device according to claim 7 or 8, wherein the input end of the regulating gas heating bypass pipe (5) is provided with a pressurizing fan (6), and the pressurizing A preheating device (8) is disposed on the regulating gas heating bypass pipe (5) between the fan (6) and the plasma heater (7).