CN216473396U - A low carbon sintering system - Google Patents

Abstract

The utility model relates to a low-carbon sintering system, belongs to the field of low-carbon metallurgy in metallurgical industry, and solves the problems of high energy consumption, carbon emission amplification, more pollutant emission and the like of the conventional sintering process. The utility model provides a low-carbon sintering system, which comprises an air source system, a hot blast stove system and a sintering system which are sequentially connected through pipelines; the air source system comprises a normal-temperature air, medium-temperature air or/and flue gas supply unit, and air from the air source system enters the hot blast stove system; the hot blast stove system provides high-temperature hot air for sintering for the sintering system. The utility model can reduce the sintering carbon blending amount and has the advantages of low energy consumption, low carbon and environmental protection.

Description

A low carbon sintering system

technical field

The utility model belongs to the low-carbon green metallurgy field of the sintering process in the metallurgical industry, in particular to a low-carbon sintering system.

Background technique

Sintering in the metallurgical process is to mix various powdered iron-containing raw materials with appropriate amount of fuel and flux, add an appropriate amount of water, and after mixing and pelletizing, a series of physical and chemical changes will occur on the material on the sintering equipment. The process of sticking together. Generally, the amount of fuel (coke powder and coal powder) in the sintering raw material is 4%, and the CO ₂ emission per ton of sinter is about 130kg; at the same time, a large amount of SO ₂ , NO _x and other pollutants are produced during the sintering process, and these The main source of waste is fuel, therefore, reducing the amount of coke powder and coal powder in sintering production can effectively reduce the emission of pollutants, and at the same time reduce the emission of CO _x in the sintering process.

The existing sintering system generally uses normal temperature air to provide oxygen for the combustion of carbon fuel in the ore blending, and also uses part of the sintering hot flue gas to circulate, using the waste heat in the flue gas for hot air sintering, and the temperature of the circulating flue gas is generally lower than 200. ℃, although it can play a role in reducing the carbon content of sintering, but it is very limited in reducing the total amount of pollutant emissions. At the same time, because the hot air adopts circulating flue gas, its oxygen content is lower than the oxygen content in the air, so it also has a certain influence on the sintering process.

CN112831652A discloses a carbon-free sintering system that uses high air temperature to provide heat. The flue gas furnace provides heat for the sintering machine, and a certain proportion of coke oven gas and air are introduced into the flue gas furnace, and the main components of the high temperature gas are formed by combustion. CO ₂ and H ₂ O, with extremely low oxygen content. Although the high-temperature gas only provides heat for the sintering process and does not participate in the chemical reaction of the sintering process, the practical application range is small, because most sintered ores need to be prepared with carbon as a reducing agent, and in a low oxygen environment, the carbonaceous reducing agent cannot play its role. effect, which greatly affects the sintering effect.

The existing hot air sintering system has very limited carbon reduction in the sintering process, and cannot achieve a significant reduction in the amount of carbon allocated for sintering, nor can it achieve a significant reduction in the emission of sintered pollutants.

Utility model content

In view of the above analysis, the purpose of a low-carbon sintering system proposed by the present utility model is to use a hot blast furnace to provide high-temperature hot air for sintering for the sintering machine. The air source system includes normal temperature air, medium temperature air or and/or flue gas supply units, from The air from the air source system enters the hot blast furnace system, and the sensible heat of the high-temperature hot air can greatly replace the heat released by the combustion of the carbon-containing fuel in the sintering raw material, thereby realizing low-carbon/ultra-low carbon sintering. The sintering system is equipped with an oxygen supply system to solve the problem. The existing sintering system has technical problems such as too low oxygen content, large coke/pulverized coal consumption, and high pollutant discharge.

In order to solve the above problems, the technical scheme adopted by the present utility model is as follows:

The low-carbon sintering system of the utility model comprises an air source system, a hot blast stove system and a sintering machine sintering system connected by pipelines in sequence;

The air source system includes normal temperature air, medium temperature air or/or a flue gas supply unit, and the air from the air source system enters the hot blast stove system;

The hot blast stove system provides high temperature hot blast for sintering for the sintering machine system.

Further, the above-mentioned hot blast stove system is composed of more than two groups of regenerative hot blast stoves, and the fuel used is one or more of methane, hydrogen and coal gas.

Further, the above-mentioned sintering machine system includes a sintering machine and a hot-air hood arranged above the sintering machine; the above-mentioned hot-air hood is connected to the hot-blast stove system through a hot-air duct, and the high-temperature hot air is sent to the sintering machine material surface through the hot-air hood.

Further, the above-mentioned low-carbon sintering system further includes an oxygen supply system, the oxygen supply system is connected with the hot air pipeline, and the oxygen supply amount of the oxygen supply system is adjustable.

Further, the above-mentioned low-carbon sintering machine system further includes a gas system, and the above-mentioned hot air hood is connected to the gas system, the gas system provides secondary temperature compensation for the sintering machine, and the gas inlet amount of the gas system is adjustable.

Further, the above-mentioned hot air hood is provided with refractory material inside, the two ends of the hot air hood are sealed, and the interior is divided into a plurality of non-connected segments.

Further, the above-mentioned low-carbon sintering system also includes a flue gas treatment system, the air inlet of the above-mentioned flue gas treatment system is connected to the flue gas pipe below the sintering machine, and the air outlet is connected to the air inlet of the hot blast stove as a flue gas supply unit.

Further, the above-mentioned low-carbon sintering system also includes a sinter cooling system, the air inlet of the sinter cooling system is fed with normal temperature air, and the air outlet is connected to the air inlet of the hot blast stove as a medium temperature air supply unit.

Further, a cold air supply system for conveying normal temperature air is used as the normal temperature air supply unit, and the cold air supply system is connected with the combustion device of the hot blast stove and the heat accumulator device of the hot blast stove at the same time.

Further, each segment of the above-mentioned hot air hood is provided with a temperature monitoring device.

Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

(1) The hot blast stove system provided by the utility model utilizes an energy-saving hot blast stove, and the air source system includes normal temperature air, medium temperature air or and/or a flue gas supply unit, and the wind from the air source system enters the hot blast stove system, and the air source system can For flue gas treatment system, sinter cooling system and/or cold air supply system, it can recycle the heat inside the entire sintering system and reduce energy consumption. At the same time, the hot blast stove provides high-temperature hot air for the sintering machine, and the sensible heat of the hot air can greatly replace the heat released by the combustion of the carbon-containing fuel in the sintering raw material, thereby realizing low-carbon/ultra-low carbon sintering.

(2) The utility model connects the oxygen supply system to the hot air main pipe of the low-temperature sintering system, and adjusts the oxygen content in the high-temperature air by monitoring the oxygen content in the high-temperature air, so that the carbon distribution in the sintering material is fully burned, and the rich Oxygen sintering.

(3) The utility model divides the high-temperature hot air hood into sections, and the pipeline is provided with a valve for adjusting the flow rate of each section, so that the amount of high-temperature air introduced into the sintering at different stages can be set; by monitoring the temperature of each section of the hot air hood, it can be known that the mineral sintering is sintered. The degree of reactivity of the sintering machine can be controlled to control the temperature of the high-temperature air entering the surface layer of the sintering machine; the outlet of the hot air hood is increased with a cyclone structure, so that the high-temperature air can be blown into the sintering material layer more uniformly, so that the reaction and combustion are more sufficient. Setting, you can monitor the sintering reactivity, adjust the amount and method of high temperature air entering, and save high temperature hot air.

(4) The low-carbon sintering system provided by the utility model can greatly reduce the content of pollutants in the sintering flue gas, realize low-carbon and low-pollutant emission from sintering, and reduce the ultra-low emission of flue gas.

(5) The low-carbon sintering system provided by the utility model can be transformed on the existing sintering process, thus saving the equipment cost, and can be widely marketed.

In the present invention, the above technical solutions can also be combined with each other to achieve more preferred combination solutions. Additional features and advantages of the invention will be set forth in the description which follows, and some of the advantages may become apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the content particularly pointed out in the description and drawings.

Description of drawings

The drawings are for the purpose of illustrating specific embodiments only, and are not considered to be a limitation of the present invention, and the same reference numerals refer to the same parts throughout the drawings.

Fig. 1 is the low carbon sintering process flow chart in embodiment 1～3;

Fig. 2 is the low carbon sintering process flow chart in embodiment 4;

Figure 3 is a schematic diagram of a hot air hood without gas injection;

Figure 3a is the left side view of the hot air hood without gas injection in the direction of A;

Figure 3b is the left side view of the D-D direction of the hot air hood without gas injection;

Figure 3c is a front view of the hot air hood without gas injection in the direction B;

Figure 3d is the rear view of the hot air hood without gas injection in the direction C;

Figure 3e is a non-segmented view of the hot air hood without gas injection in the direction of E-E;

Figure 3f is a segmented view in the direction E-E of the hot air hood without gas injection;

Figure 4 is a schematic diagram of a hot air hood with gas injection;

Figure 4a is a left side view of the hot air hood with gas injection in the direction of A;

Figure 4b is the left side view of the hot air hood with gas injection in the direction of D-D;

Figure 4c is a front view of the hot air hood B with gas injection;

Figure 4d is a rear view of the hot air hood with gas injection in the direction C;

Figure 4e is a non-segmented view of the hot air hood with gas injection in the direction of E-E;

Figure 4f is a segmented view in the direction E-E of the hot air hood with gas injection;

FIG. 5 is a schematic diagram of the cyclone structure of the nozzle of the hot air branch pipe.

Reference number:

1-Hot blast stove; 2-Sintering machine; 3-Oxygen supply system; 4-Hot blast main pipe; 5-Hot blast hood; 6-Gas system; 7-Gas main pipe; 8-Hot blast branch pipe; 9-Hot blast branch pipe valve; 10-Gas Branch pipe; 11- gas branch pipe valve; 12- large flue; 13- dust removal system; 14- exhaust fan; 15- chimney; 16- flue gas treatment system; 17- fan blade; 18- shaft; 19- fan blade holes.

Detailed ways

The preferred embodiments of the present utility model will be specifically described below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present utility model, and together with the embodiments of the present utility model, are used to explain the principles of the present utility model, but are not intended to limit the present utility model. range.

The utility model discloses a low-carbon sintering system, which comprises an air source system, a hot blast stove system and a sintering machine system which are connected by pipelines in sequence;

The air source system includes normal temperature air, medium temperature air or/or a flue gas supply unit, and the air from the air source system enters the above-mentioned hot blast stove system;

The hot blast stove system provides high temperature hot blast for sintering for the sintering machine system.

In the air source system, the normal temperature air supply unit can be a cold air supply system, and a cold air supply system for conveying normal temperature air is used as the normal temperature air supply unit.

The cold air supply system provides normal temperature air for the combustion of the fuel of the hot blast stove, and at the same time provides the normal temperature air source for the high temperature air of the hot blast stove, and the supply amount and pressure of the normal temperature air can be adjusted according to the needs. The cooling system cools the sintered ore at 700-900°C to below 200°C by introducing air, and at the same time discharges medium-temperature air. The general temperature range is 200°C-600°C.

Specifically, the cold air supply system is a normal temperature air conveying device, and the normal temperature air is pumped and connected to the heat accumulator device of the hot blast stove through a pipeline to provide normal temperature air for the hot blast stove, that is, the normal temperature air supply unit of the air source system.

On the one hand, the cold air supply system provides conventional air for the combustion of the fuel of the hot blast stove, and on the other hand, provides the air source to be heated for the regenerator of the hot blast stove, and the supply amount and pressure of the air can be adjusted through the valve.

In order to circulate the heat inside the system and reduce energy consumption, the medium temperature air supply unit can be a sinter cooling system. The air inlet of the sinter cooling system is fed with normal temperature air, and the air outlet is connected to the air inlet of the hot blast stove as a medium temperature air supply. The flue gas supply unit can be a flue gas treatment system. The flue gas comes from the sintering machine and enters the flue gas treatment system through the flue gas pipe under the sintering machine. The air inlet of the flue gas treatment system is connected to the flue gas pipe under the sintering machine. , the air outlet is connected to the air inlet of the hot blast stove as a flue gas supply unit.

Specifically, the outlet of the flue gas treatment system of the sintering machine is connected to the hot blast furnace through a pipeline; a sintering ore cooling system is correspondingly provided at the unloading end of the sintering machine for cooling the sintering ore. The gas outlet of the ore cooling system is connected with the air inlet of the hot blast stove through pipes; the medium-temperature air obtained by cooling is sent to the hot blast stove to realize the circulation of hot air, and the cooled sinter is ready for use.

Specifically, the flue gas pipe under the sintering machine is connected to the air inlet of the hot blast stove through the flue gas treatment system. The sintering hot smoke generated by the sintering machine is partially purified by the flue gas treatment system and used as the air source of the hot blast stove. flue gas supply unit.

Specifically, the cooling medium introduced into the air inlet of the sinter cooling system is normal temperature air. The cooling system cools the sinter at 700-900°C to below 200°C through normal temperature air, and at the same time discharges medium temperature air. The general temperature range of medium temperature air is 200℃-600℃, the air outlet of the cooling system is connected to the air inlet of the hot blast stove, and the medium temperature air is sent into the hot blast stove through the pipeline, which is the medium temperature air supply unit of the air source system.

The normal temperature air and/or flue gas and medium temperature air are introduced into the hot blast stove system, and become high temperature air to provide the sintering system with high temperature hot air for sintering, and the high temperature hot air is sent to the sintering machine material surface through the hot air hood.

Specifically, the hot blast stove system consists of two or more groups of regenerative hot blast stoves, and the fuel used is one or more of methane, hydrogen, and coal gas. The regenerative hot blast stove system can provide high-temperature hot air for the sintering machine. The regenerative hot blast stove heats the regenerator in the hot blast stove by burning combustible gas, and the regenerator stores the heat; normal temperature air and/or flue gas, Medium temperature air, the heat storage body transfers heat to normal temperature air and/or flue gas, medium temperature air, and becomes high temperature air, the maximum temperature can reach 1300 ℃, and it is passed into the sintering machine.

Specifically, a hot air hood is arranged above the sintering machine; the hot air hood is connected to the hot air furnace through a hot air duct.

More specifically, the hot air hood communicates with the hot air furnace through a hot air duct for providing sintering heat; a flue gas pipe is correspondingly arranged below the sintering machine, and the flue gas pipe leads into the large flue and is connected to the exhaust fan.

More specifically, a flue gas pipe is provided below the sintering machine (the location of which is not shown in Figure 1), the flue gas pipe is connected to a large flue, and the large flue is connected to the air inlet of the extraction fan, which will pass through the sintering machine. After the exhaust gas is collected through the flue gas pipe, it is circulated into the hot air hood through the large flue, the exhaust fan and the connecting pipe, which is used to control the air temperature in the hot air hood and realize the recycling of the hot flue gas.

The hot blast hood is communicated with the hot blast stove through pipes. The hot blast pipe includes a hot blast main pipe and a hot blast branch pipe. During operation: the hot blast stove provides high-temperature hot air for sintering; Enter the high temperature hot air hood, the high temperature hot air is sent to the material surface of the sintering machine and enters the material layer of the sintering machine, heating the sintering material layer and burning the carbon in the material layer from top to bottom, the sintering flue gas is discharged from the large flue of the sintering machine and then enters the flue gas processing system.

More specifically, the hot air pipeline includes a hot air main pipe and a hot air branch pipe, and the oxygen supply system is connected to the hot air main pipe. The hot air main pipe and the hot air branch pipe are thermal insulation pipes with refractory materials inside. It is a heat-resistant hot air flow control valve, and the heat-resistant temperature is 1300 °C.

It should be noted that the top-down combustion process is achieved through bottom extraction.

Flow regulating valves are provided between the hot blast hood and the hot blast stove (on the hot blast branch pipe) and on the connecting pipes between the hot blast hood and the exhaust fan, and the valves are high temperature resistant flow regulating valves. By setting the flow regulating valve, the opening of the flow regulating valve can be controlled according to the production output demand and the thickness of the material layer of the cloth. On the one hand, the opening of the flow control valve is used to control the high temperature air flow and the exhaust gas flow into the hot blast stove, so as to control the hot air temperature; At the same time change the wind speed. Exemplarily, by using the opening of the flow regulating valve to control the hot air temperature and wind speed in each section of the hot air hood, when the material layer is thicker, the opening of the flow regulating valve is correspondingly larger, and when the production demand increases, By increasing the opening of the flow control valve and increasing the hot air flow and air temperature, the speed of the sintering machine can be simultaneously increased, the sintering process can be accelerated, the output can be increased, and the production demand can be met.

The high-temperature air nozzle of the high-temperature hot air hood leading into the sintering machine is provided with a cyclone structure, so that the high-temperature air is blown into the sintering material layer more uniformly, so that the reaction is more sufficient and the combustion is more sufficient. Specifically, the cyclone structure is composed of a shaft and a plurality of fan blades. In order to introduce high-temperature air into a larger area, the fan blades are provided with holes.

Specifically, the above-mentioned sintering system further includes an oxygen supply system and a fuel gas system.

Specifically, the above-mentioned oxygen supply system is connected to the hot air pipeline, and an oxygen supply flow regulating valve is provided to inject oxygen into the high temperature hot air to adjust the oxygen content in the high temperature hot air.

According to the above, if the normal temperature air from the cold air supply system is fed into the hot blast stove, it becomes high temperature air through the hot blast stove and is fed into the sintering machine. In theory, the oxygen content of the high temperature air is the same as that of the normal temperature air. The hot blast stove is part of the hot flue gas in the sintering machine, and the oxygen content is only 15%-20%. Achieve oxygen-rich sintering. Increasing the oxygen content of the high-temperature air is conducive to the full combustion of the added fuel in the sintered material layer, improves the combustion efficiency of the fuel, and reduces the carbon content of the sintering.

More specifically, the oxygen supply system monitors the oxygen content in the high-temperature air in real time, and according to the set oxygen content, controls the amount of oxygen that is fed into the high-temperature air through the oxygen supply flow regulating valve (automatic air supply valve), and then starts. To adjust the oxygen content in the high-temperature air, oxygen-enriched sintering can be achieved, and the oxygen content (volume percentage) in the high-temperature air ranges from 21 to 50%; the amount of oxygen introduced into the oxygen supply system is calculated by the following formula:

Where: R is the set oxygen volume fraction in the high-temperature air; M is the high-temperature air volume introduced per unit time, m ³ /min; n is the original oxygen volume fraction in the high-temperature air; X is the unit time requirement of the oxygen supply system The amount of oxygen introduced, m ³ /min.

Specifically, the above-mentioned hot air hood is connected to the gas system, the gas system provides secondary temperature supplementation for the sintering machine, and the gas branch pipe is provided with a gas branch pipe valve to adjust the gas inlet amount.

When the high temperature hot air enters the hot air hood, there is heat loss. In the case of high temperature sintering, or when the heat loss of the high temperature hot air is large, the function of the gas system is to supplement the gas when the hot air enters the high temperature hot air hood in the sintering material layer. The high temperature hot air is reheated to make the high temperature air temperature higher. After the gas is burned, the temperature of the hot air is adjusted to ensure that the temperature of the hot air is within the set range, which is conducive to the stability of the temperature of the high-temperature hot air, and at the same time to ensure the stability of the carbon content of the hot air instead of sintering.

Specifically, the above-mentioned hot air hood has refractory material inside, and the gap between the hot air hood and the trolley fence is less than 10 mm; both ends of the hot air hood are sealed; the interior of the hot air hood can be divided into multiple disconnected segments.

The small gap between the hot air hood and the trolley fence is beneficial to prevent the leakage of high-temperature air from the gap, which is beneficial to improve the utilization rate of hot air and reduce the waste of high-temperature air.

More specifically, the interior of the hot air hood can be divided into a plurality of disconnected sections, which are mainly divided into three main sections, such as the first-stage hot-air hood, the second-stage hot-air hood, and the third-stage hot-air hood, which are set according to the different stages of sintering. , one of the hot air hoods mainly corresponds to 1/4 of the material surface of the front end of the sintering machine. This stage is in the stage of forming a sintering belt on the surface of the material layer; After the first section of hot air hood corresponds to the material surface, a certain thickness of sintering belt has been formed on the upper part of the sintered material layer at this stage; After the second-stage hot air hood corresponds to the material surface, the sintered material layer at this stage is nearly finished sintering.

The hot air hood is set up with multiple segments, and the segmented control sintering is more precise. Specifically, the hot air temperature from the temperature monitoring system on the hot air hood is fed back to the gas system, and the difference between the hot air temperature and the target temperature is compared to calculate the amount of gas required to increase the current temperature to the target temperature, and control the hot air flow into the hot air hood.

Specifically, the low-temperature sintering system further includes a flue gas treatment system, the air inlet of the flue gas treatment system is connected to the flue gas pipe below the sintering machine, and the air outlet is connected to the air inlet of the hot blast stove as a flue gas supply unit.

The utility model adopts an energy-saving hot blast stove that utilizes hot air, sintering waste gas, etc. The hot blast stove provides high-temperature hot air for the sintering machine, and the sensible heat of the hot blast can greatly replace the heat released by the combustion of the carbon-containing fuel in the sintering raw materials, thereby realizing low carbon/ Ultra-low carbon sintering, and the air source of the hot blast stove can come from the sintering machine, the sinter cooling system and/or the cold air supply system, and the heat inside the system can be recycled to reduce energy consumption.

Compared with the prior art, the low-carbon sintering process method of the present invention changes the normal temperature air used in traditional sintering, and can realize high-temperature hot air (such as air, sintering flue gas and/cooling medium air) of 500° C. to 1300° C. Sintering process, and provide heat for sintering to replace part of the sintered material with carbon, to achieve low-carbon green sintering.

Compared with the prior art, the oxygen supply system of the present utility model monitors the oxygen content in the high-temperature air in real time, and controls the amount of oxygen that is fed into the high-temperature air through the automatic air supply valve according to the set oxygen content, thereby starting the operation. To adjust the oxygen content in the high temperature air, oxygen-enriched sintering can be achieved.

Compared with the prior art, the hot blast stove system provided by the utility model is an energy-saving hot blast stove using hot air. The high temperature hot air provided by the hot blast stove for sintering comes from three parts: sintering machine and sinter cooling system. , Cold air supply system, the heat inside the system is recycled to reduce energy consumption.

Example 1

This embodiment provides a low-carbon sintering system, and the system device is shown in FIG. 1 . The specific details are as follows:

The hot blast stove 1 is composed of one or more groups of regenerative hot blast stoves. The air inlet pipe of the hot blast stove system is divided into two paths, one branch pipe is connected to the regenerator of the hot blast stove, and the other branch pipe is connected to the combustion device of the hot blast stove. The normal temperature air and/or flue gas and medium temperature air are heated by the regenerative hot blast furnace into high temperature hot air to provide high temperature hot air for sintering.

The high-temperature hot air first passes through the hot-air main pipe 4, and then passes the high-temperature air into the hot-air hood 5 through the hot-air branch pipe valve 9 on the hot-air branch pipe 8 connected to the hot-air main pipe. 2. The material surface enters the material layer of the sintering machine, and the exhaust fan 14 connected to the flue gas pipeline under the sintering machine draws out the air to form a negative pressure, so that the high-temperature hot air enters the material layer, heats the sintering material layer and burns the material in the material layer from top to bottom. When the oxygen content of the high-temperature hot air in the hot air hood 5 is low, the oxygen supply system 3 is automatically activated to realize oxygen-enriched sintering; when the sensible heat of the high-temperature hot air in the hot air hood cannot meet the operating requirements, the gas system 6 is activated, Through the control of the gas branch pipe valve 11 on the gas branch pipe 4, the high temperature hot air in the hot air hood is supplemented for the second time to meet the requirements of the sintering operation.

The flue gas generated by sintering is discharged from the flue gas pipe below the sintering machine, connected to the large flue 12, and then enters the flue gas treatment system 16; the outlet of the flue gas treatment system 16 is connected to the air inlet of the hot blast stove through a pipe; the sintering machine 2 enters after discharging. In the sinter cooling system, the gas outlet of the sinter cooling system is connected with the air inlet of the hot blast furnace through pipes; the high temperature hot air circulation and the thermal circulation in the system are realized.

The remaining sintering flue gas is treated by the dust removal system 13 and the flue gas treatment system 16 to meet the emission requirements, and then discharged through the chimney 15 .

Example 2

This embodiment provides a low-carbon sintering system, and the system device is shown in FIG. 1 . Specific details of practical applications and beneficial effects are as follows:

This embodiment is a 400m ² sintering machine. First, the hot blast stove is composed of two groups of hot blast stoves, using hydrogen as the fuel, and the high temperature hot blast temperature generated by the hot blast stove is 1000°C. The air source of the high-temperature hot air provided by the hot blast stove for sintering includes two parts. One part comes from the hot air from the sinter cooling system, and the air temperature is 450°C. The hot air provided by the sinter cooling system can reduce the energy consumption of the hot blast stove by more than 15%; the other part Room temperature air from a cold air supply system.

The cooling medium of the sinter cooling system is air, which cools the sinter at 760°C to 180°C, and at the same time discharges 450°C medium-temperature air to provide 60% of the hot air volume for the sintering machine. The sinter cooling system uses a vertical cooler, which can achieve The maximum recovery of sensible heat of sinter;

The cold air supply system provides air for the combustion of the fuel of the hot blast stove 1, and provides air source for the high temperature hot air of the hot blast stove, and the air it provides accounts for 40% of the large amount of hot air required by the sintering machine;

The oxygen supply system is connected with the hot air pipeline, and oxygen is introduced into the hot air before the high temperature hot air enters the high temperature hot air cover of the sintering machine to make the oxygen content in the high temperature hot air reach 25%. The oxygen supply system calculates the amount of oxygen that needs to be injected into the hot air duct according to the air volume provided by the sinter cooling system, the air volume supplied by the cold air supply system, and the set 25% oxygen content.

There is a high-temperature hot air hood on the material surface of the sintering machine, and there is a refractory material inside the hot air hood, and the gap between the hot air hood and the trolley fence is less than 10mm; both ends of the hot air hood are sealed, and the interior of the hot air hood is divided into 3 disconnected sections. Internally disconnected.

The hot smoke from the sintering machine passes through the flue gas treatment system and is only dedusted, and the exhaust flue gas meets the latest ultra-low emission standards.

In Example 1, the SO ₂ content in the exhaust gas is less than 30 mg/Nm ³ , the NOx content is less than 50 mg/Nm ³ , and the dust content is less than 10 mg/Nm ³ , meeting the latest ultra-low emission standards. At the same time, the high temperature hot air circulation sintering can reduce the carbon content in the sintering raw materials by more than 70%.

Example 3

This embodiment provides a low-carbon sintering system, and the above-mentioned sintering system is applied to actual production, and the process flow chart is shown in FIG. 1 . The specific details are as follows:

This embodiment is a 360m2 sintering machine ² for producing sintered ore, and the raw material is iron ore powder mixture. In the traditional condition, that is, the batching parameters under the condition of no hot air are shown in Table 1, and the air volume required for traditional sintering is 25.5 million Nm ³ /h.

Table 1 Parameters of sintering ingredients under traditional conditions

First, the normal temperature air passes through the hot blast stove 1 and becomes high temperature air of 1000°C; then the high temperature hot air passes through the hot blast main pipe 4, and then passes the high temperature hot air into the high temperature hot blast hood 5 through the 6 hot blast branch pipes 8 connected to the hot blast main pipe. The high-temperature hot air is sent to the sintering machine 2 material surface; finally, the high-temperature hot air enters the sintering material layer from the sintering machine 2 material surface, heats the sintering material layer and burns the carbon in the material layer from top to bottom, and realizes the sintering process of the material layer. The parameters of sintering ingredients after hot air are introduced are shown in Table 2.

Table 2 Parameter list of sintering ingredients under the condition of hot air (1000℃)

The fuel used in the hot blast stove is methane, which is heated to 1000 ℃ after the hot blast stove at room temperature; at the same time, the oxygen supply system 3 is connected to the hot blast main pipe 4, and the oxygen supply system can increase the oxygen content in the high temperature hot blast by introducing oxygen into the high temperature hot blast , to increase the oxygen content in the high temperature hot air to 25%. Under this condition, the hot air volume required for sintering is 15.3 million Nm ³ /h, the air volume is reduced by 40%, and the amount of fuel added can be reduced by 80%.

Both the hot air main pipe 4 and the hot air branch pipe 8 are thermal insulation pipes with refractory materials inside, and the hot air branch pipe valve 9 on the hot air branch pipe 8 is a high temperature resistant hot air valve, and the heat resistance temperature is 1300 ℃.

The high temperature hot air hood 5 is a hot air hood on the sintering machine. The high temperature hot air hood 5 has refractory materials inside, and the gap between the hot air hood and the trolley fence is less than 10mm; both ends of the high temperature hot air hood 5 are sealed; the interior of the high temperature hot air hood 5 can be divided There are 6 disconnected segments, which are segment 1, segment 2, segment 3, segment 4, segment 5, segment 6 in the order from the head to the tail; among them, segment 1 corresponds to It is a 1-stage hot air hood, the 2, 3, 4, and 5 sections generally correspond to the 2-stage hot-air hood, and the 6-stage corresponds to the 3-stage hot-air hood; 9 to control the incoming hot air volume of each segment.

The high temperature hot air hood 5 is connected to the gas system 6, and the methane provided by the gas system 6 is connected to the high temperature hot air hood 5 through the gas main pipe 7 and the gas branch pipe 10. The gas branch pipe 10 is connected to a segment inside the high temperature hot air hood 5 .

The flue gas of the sintering machine passes through the large flue 12 and enters the dust removal system 13 for dust removal, then passes through the induced draft fan 14, and finally is discharged from the chimney 15.

The SO ₂ content in the exhaust gas in Example 3 is <30 mg/Nm ³ , the NOx content is < 50 mg/Nm ³ , and the dust content is < 10 mg/Nm ³ , meeting the latest ultra-low emission standards. At the same time, the high temperature hot air sintering reduces the carbon content in the sintered material from 3% to less than 0.6%, which can reduce the carbon content in the sintered raw material by more than 80%.

Example 4

This embodiment provides a low-carbon sintering system, and the above-mentioned sintering system is applied to actual production, and the process flow chart is shown in FIG. 2 . The specific details are as follows:

This embodiment is a 360m ² sintering machine for producing sintered ore, and the raw material is iron ore powder mixture. In the traditional condition, that is, the batching parameters under the condition of no hot air are shown in Table 3, and the air volume required for traditional sintering is 25.5 million Nm ³ /h.

Table 3 Parameters of sintering ingredients under traditional conditions

First, the normal temperature air passes through the hot blast furnace and becomes high temperature air at 1150°C; then the high temperature air passes through the hot blast main pipe, and then passes the high temperature air into the high temperature hot blast hood through the 6 hot blast branch pipes connected to the hot blast main pipe, and then the high temperature hot air is sent to the sintering machine material surface; finally, the high-temperature hot air enters the sintering material layer from the sintering machine material surface, heats the sintering material layer and burns the carbon in the material layer from top to bottom, and realizes the sintering process of the material layer. The parameters of sintering ingredients after hot air are introduced are shown in Table 4.

Table 4 Parameters of sintering ingredients under the condition of hot air (1150℃)

The fuel used in the hot blast stove is methane, which is heated to 1150 ℃ after the hot blast stove at room temperature; at the same time, an oxygen supply system is connected to the hot blast main pipe. The oxygen supply system can increase the oxygen content in the high temperature air by introducing oxygen into the high temperature air, and The oxygen content in the high temperature air is increased to 25%. Under this condition, the hot air volume required for sintering is 12.75 million Nm ³ /h, the air volume is reduced by 50%, and the fuel dosage can be reduced by 90%.

In Example 4, the SO ₂ content in the exhaust gas is <30 mg/Nm ³ , the NOx content is < 50 mg/Nm ³ , and the dust content is < 10 mg/Nm ³ , meeting the latest ultra-low emission standards. At the same time, the high temperature hot air sintering reduces the carbon content in the sintered material from 3% to less than 0.4%, which can reduce the carbon content in the sintered raw material by 90%.

Example 4 also provides an anti-overburning system for sintered ore. If the temperature of the hot air reaches 1170 °C and above, the anti-overburning system is activated, and an appropriate amount of room temperature air is blown into the hot air main pipe to mix with the hot air to ensure that it enters the high-temperature hot air hood. The hot air temperature in 5 is in the range of 1150±20℃.

The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. The changes or replacements should be covered within the protection scope of the present invention.

Claims (10)

1. a low-carbon sintering system, is characterized in that, comprises the air source system, the hot blast stove system and the sintering machine sintering system that the pipeline is connected successively; The air source system includes normal temperature air, medium temperature air or/or a flue gas supply unit, and the air from the air source system enters the hot blast stove system; The hot blast stove system provides high temperature hot blast for sintering for the sintering machine system. 2 . The low-carbon sintering system according to claim 1 , wherein the hot blast stove system consists of two or more groups of regenerative hot blast stoves. 3 . 3. The low-carbon sintering system according to claim 1, wherein the sintering machine system comprises a sintering machine and a hot air hood arranged above the sintering machine; the hot air hood is connected to the hot air furnace system through a hot air duct, and the high temperature The hot air is sent to the material surface of the sintering machine through the hot air hood. 4 . The low-carbon sintering system according to claim 3 , wherein the low-carbon sintering system further comprises an oxygen supply system, the oxygen supply system is connected with the hot air pipeline, and the oxygen supply amount of the oxygen supply system is adjustable. 5 . 5 . The low-carbon sintering system according to claim 3 , wherein the low-carbon sintering machine system further comprises a gas system, the hot air hood is connected to the gas system, and the gas system provides secondary temperature compensation for the sintering machine, 6 . And the gas inlet volume of the gas system is adjustable. 6 . The low carbon sintering system according to claim 3 , wherein a refractory material is provided inside the hot air hood, both ends of the hot air hood are sealed, and the interior is divided into a plurality of disconnected segments. 7 . 7 . The low-carbon sintering system according to claim 1 , wherein the low-carbon sintering system further comprises a flue gas treatment system, and an air inlet of the flue gas treatment system is connected to a flue gas pipe below the sintering machine. 8 . , the air outlet is connected to the air inlet of the hot blast stove as a flue gas supply unit. 8 . The low-carbon sintering system according to claim 1 , wherein the low-carbon sintering system further comprises a sinter cooling system, the air inlet of the sinter cooling system is fed with normal temperature air, and the air outlet is connected to the hot blast stove. Air intake as medium temperature air supply unit. 9 . The low-carbon sintering system according to claim 1 , wherein a cold air supply system for conveying normal temperature air is adopted as the normal temperature air supply unit, and the cold air supply system is simultaneously connected to the combustion device of the hot blast stove and the heat accumulator device of the hot blast stove. 10 . . 10 . The low-carbon sintering system according to claim 3 , wherein a temperature monitoring device is provided in each section of the hot air hood. 11 .

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