Method for preparing blast furnace injection fuel through dezincification of waste tire pyrolysis carbon black

Abstract

The invention discloses a method for preparing blast furnace injection fuel through dezincification of waste tire pyrolysis carbon black. The method comprises the steps of pyrolysis of waste tires in a flame-separation rotary cracking furnace, dezincification of pyrolysis carbon black in a flame-separation rotary dezincification furnace, blast furnace injection of dezincification pyrolysis carbon black instead of pulverized coal and the like. By controlling the reaction temperature and time of the rotary cracking furnace and the dezincification furnace, the waste tires with lower utilization value are converted into dezincification cracking carbon black with high heating value and low harmful element content, and high-value pyrolysis oil and zinc oxide are obtained at the same time; the dezincification cracking carbon black and pulverized coal are mixed and then enter a blast furnace tuyere for combustion through a coal pulverizing system and an injection system, and a heat generating agent and reduction are provided for blast furnace production. According to the invention, hydrogen-rich combustible gas and preheating gas in the reaction are recycled, so that the energy consumption can be reduced, the resource utilization rate can be increased, and the environmental pollution can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of waste tire resource utilization, and particularly to a method for preparing blast furnace injection fuel by removing zinc from waste tire pyrolysis carbon black. Background Art

[0002] With the rapid development of the automotive industry in China, a large amount of waste tires are generated every year. How to utilize them in a high-value and harmless way has become an important issue faced by the current industry. Waste tires are difficult-to-treat flexible polymer wastes and are not easily degradable. Conventional treatment methods are difficult to efficiently process them. Generally, incineration combined with landfill measures are used for harmless treatment, but adverse environmental impacts will also occur during incineration and landfill. High-temperature pyrolysis of waste tires is an important means of high-value and harmless treatment. After high-temperature pyrolysis of waste tires, products such as pyrolysis oil, hydrogen-rich combustible gas, pyrolysis carbon black, and waste steel wire can be obtained. Pyrolysis carbon black has the characteristics of high fixed carbon content and high calorific value. If it is used to replace pulverized coal for blast furnace injection in ironmaking production, the use value of pyrolysis carbon black will be effectively improved.

[0003] During the tire production process, substances such as zinc oxide need to be added to promote its vulcanization. During high-temperature pyrolysis, zinc oxide finally remains in the pyrolysis carbon black, resulting in too high zinc oxide content in the pyrolysis carbon black. Zinc oxide has a serious negative effect on blast furnace smelting. How to reduce the zinc oxide content in pyrolysis carbon black has become a research hotspot. Methods for reducing zinc oxide in pyrolysis carbon black include physical methods and chemical methods. Physical methods require fine pulverization and separation of pyrolysis carbon black, but due to the nano-scale structure and complex composition in pyrolysis carbon black, the separation effect is poor, and there is a lot of residual zinc, which is difficult to meet the requirements of blast furnace injection. Chemical methods mainly use pickling. Although it can effectively reduce the zinc oxide content in pyrolysis carbon black, a large amount of strong acids and other chemical reagents are consumed during the treatment process, and environmental problems such as wastewater, waste acid, and waste alkali emissions will also be caused. Summary of the Invention

[0004] The purpose of the present invention is to address the above problems. The present invention provides a method for preparing blast furnace injection fuel by removing zinc from waste tire pyrolysis carbon black. By controlling the high-temperature roasting and reduction reaction conditions of pyrolysis carbon black, efficient reduction and removal of zinc oxide are achieved, and a de-zincified pyrolysis carbon black product with high fixed carbon, high calorific value, low ash, and low zinc content is prepared. At the same time, high-value recycling of zinc oxide is realized. On the one hand, the use value of by-products in the waste tire pyrolysis industry is improved, and on the other hand, high-quality and low-cost coal substitute fuel is provided for the steel industry, which has positive economic and ecological significance.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for preparing blast furnace injection fuel by removing zinc from waste tire pyrolysis carbon black includes the following steps:

[0007] (1) The waste tires are crushed into a certain particle size and then loaded into a muffle rotary pyrolysis furnace through a conveying and feeding device for pyrolysis to obtain pyrolysis oil gas and pyrolysis carbon black;

[0008] (2) The pyrolysis oil gas is cooled through a heat exchanger to separate pyrolysis oil and hydrogen-rich combustible gas, and the hydrogen-rich combustible gas is used as fuel for the muffle rotary pyrolysis furnace and the muffle rotary dezincing furnace;

[0009] (3) The listed pyrolysis carbon black is added to a muffle rotary dezincing furnace through a hot conveying device for high-temperature roasting and reduction dezincing to generate zinc-containing gas and dezincified pyrolysis carbon black;

[0010] (4) The zinc-containing gas is roughly purified in an oxidation settling chamber, the coarse particles at the bottom of the settling chamber are returned to the muffle rotary dezincing furnace, and the zinc vapor is oxidized into fine zinc oxide particles and enters the heat exchanger with the high-temperature flue gas;

[0011] (5) The high-temperature zinc-containing flue gas enters a bag filter after being cooled by a heat exchanger, and zinc oxide products are obtained after being filtered by the bag filter. The remaining flue gas is directly discharged after meeting the waste emission standards through a purification system;

[0012] (6) The dezincified pyrolysis carbon black is cooled through a cooling cylinder, and the waste steel wires contained in the cooled dezincified pyrolysis carbon black are removed by a magnetic separator;

[0013] (7) The dezincified pyrolysis carbon black is mixed with pulverized coal for blast furnace injection and then transported to a coal pulverizing system for pulverization. The pulverized mixed material is transported to the tuyere raceway of the blast furnace through a blowing system for combustion to provide heat and reducing agents for blast furnace smelting.

[0014] Further, the particle size of the waste tires after crushing treatment in step (1) is less than 5 cm.

[0015] Further, the working temperature of the muffle rotary pyrolysis furnace in step (1) is 350 - 850 °C, and the residence time of the waste tire particles in the muffle pyrolysis furnace is 30 - 350 min.

[0016] Further, the yield of the pyrolysis oil gas in step (1) is 40% - 70%, the temperature of the pyrolysis oil gas is 300 °C - 800 °C, the yield of the pyrolysis carbon black is 30% - 60%, and the temperature of the pyrolysis carbon black is 350 °C - 850 °C.

[0017] Further, after the high-temperature pyrolysis oil gas is cooled by a heat exchanger in step (2), pyrolysis oil is condensed and precipitated, the yield of pyrolysis oil is 30% - 50%, and the yield of the remaining hydrogen-rich combustible gas is 10% - 20%.

[0018] Further, in step (2), the cooling medium of the pyrolysis oil and gas in the heat exchanger is combustion-supporting air, and the combustion-supporting air is preheated to 200°C - 600°C in the heat exchanger. The preheated combustion-supporting air is used for the combustion of hydrogen-rich combustible gas in the combustion chambers of the muffle rotary pyrolysis furnace and the muffle rotary dezincing furnace.

[0019] Further, in step (3), the roasting temperature of the pyrolytic carbon black in the muffle rotary dezincing furnace is 1050°C - 1300°C, and the roasting time is 30 min - 160 min. Through roasting, zinc oxide in the pyrolytic carbon black is reduced to form zinc vapor, and the zinc vapor is discharged out of the furnace with the high-temperature gas.

[0020] Further, in step (4), the zinc-containing gas undergoes rough dust removal in the oxidation sedimentation chamber, and the zinc content in the coarse particles obtained is 0.5% - 3.5%. It is returned to the muffle rotary dezincing furnace for dezincing treatment again. The purified zinc-containing gas undergoes an oxidation reaction with excessive air, and the metallic zinc vapor is oxidized into high-grade zinc oxide dust. The temperature of the high-temperature zinc-containing flue gas is controlled at 800°C - 1200°C by adjusting the amount of oxidation air.

[0021] Further, in step (5), the temperature of the high-temperature zinc-containing flue gas is reduced to 150°C - 250°C after passing through the heat exchanger. Zinc oxide products are collected by a bag filter, and the grade of zinc oxide is 60% - 70%. The remaining flue gas is directly discharged after meeting the waste emission standards through the purification system, and the high-temperature and high-pressure steam generated by the heat exchanger is supplied for external use.

[0022] Further, in step (6), the temperature of the dezincing pyrolytic carbon black after being cooled by the cooling cylinder is 150°C - 200°C. The fixed carbon content of the dezincing pyrolytic carbon black after removing waste steel wires is greater than 75%, the volatile matter content is less than 5%, the ash content is less than 20%, the calorific value is greater than 24 MJ / kg, and the zinc element content is less than 0.5%.

[0023] Further, in step (7), the types of pulverized coal for blast furnace injection include one or more mixtures of lignite, bituminous coal, lean coal, anthracite, semi-coke, coke fines, and other carbon-containing fuels. The mass ratio of dezincing pyrolysis in the blast furnace injection mixed fuel is 1% - 60%.

[0024] The beneficial effects of the present invention are as follows:

[0025] 1. The continuous progress of the waste tire pyrolysis and the dezincing of pyrolytic carbon black is realized. The processes of waste tire pyrolysis, pyrolytic carbon black dezincing, and zinc oxide product recovery do not require the cooling of the pyrolysis furnace and the dezincing furnace, which improves the efficiency of waste tire pyrolysis and pyrolytic carbon black dezincing reactions and reduces the energy loss caused by the system cooling during the pyrolysis and dezincing processes.

[0026] 2. Reduced the pollutant emissions during the process of upgrading the quality of waste tire pyrolysis carbon black by removing zinc. The zinc removal process of pyrolysis carbon black is carried out by heating, roasting and reduction. Zinc oxide is reduced to generate zinc vapor and removed, without consuming a large amount of chemical reagents such as strong acids and strong alkalis, avoiding the generation and treatment of waste liquid, and meeting the raw materials for the resource utilization and harmless treatment of waste tires.

[0027] 3. Expanded the application scenarios and usage values of waste tire pyrolysis carbon black. In this invention, the waste tire pyrolysis carbon black with high ash content and high zinc content is de-zincified by high-temperature roasting and reduction. The prepared de-zincified pyrolysis carbon black has the characteristics of high fixed carbon content, high calorific value and low zinc content, and can be used as a high-quality low-carbon fuel to replace pulverized coal for blast furnace injection, improving the usage value of waste tire pyrolysis carbon black.

[0028] 4. Improved the product quality and usage value of zinc oxide during the zinc removal process. Through the secondary oxidation of high-temperature zinc-containing gas, the zinc vapor in the high-temperature zinc-containing gas is oxidized to zinc oxide, and the zinc oxide is captured and collected by a bag filter to obtain a high-quality zinc oxide product, which has the characteristics of low impurity content and high application value, realizing the high-value application of by-products during the process of upgrading the quality of pyrolysis carbon black by removing zinc.

[0029] The method for preparing blast furnace injection fuel by upgrading the quality of waste tire pyrolysis carbon black in this invention effectively improves the quality of pyrolysis carbon black, and at the same time can recover zinc oxide products. While improving the profitability of waste tire pyrolysis enterprises, it also provides a high-quality alternative product to pulverized coal fossil fuel for blast furnace ironmaking production in the steel industry, providing important technical support for cost reduction and carbon reduction in the steel industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a flow chart of the method for preparing blast furnace injection fuel by de-zincifying waste tire pyrolysis carbon black in this invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The following further details the present invention in conjunction with the drawings and embodiments, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope protected by the present invention.

[0032] Example 1

[0033] This example provides a method for preparing blast furnace injection fuel by de-zincifying waste tire pyrolysis carbon black. Taking the waste tires from automobile dismantling as an example, the process is as Figure 1 shown, and includes the following steps:

[0034] (1) The waste tires disassembled from household cars are crushed into pieces with a particle size less than 5 cm by a shearing machine, conveyed to a high-level storage bin by a belt conveyor, and added into a muffle rotary pyrolysis furnace through the high-level storage bin for pyrolysis treatment. The working temperature of the pyrolysis constant temperature zone of the muffle rotary pyrolysis furnace is 650 °C, and the residence time of the waste tire pieces in the pyrolysis furnace is 60 min. After the pyrolysis reaction, the yield of pyrolysis oil gas at 620 °C is 58%, the yield of pyrolysis carbon black at 630 °C is 45%, and the zinc oxide content in the pyrolysis carbon black is 8.5%. It is necessary to reduce the zinc content to meet the requirements of blast furnace production.

[0035] (2) The high-temperature pyrolysis oil gas generated by the muffle rotary pyrolysis furnace transfers heat to the combustion-supporting air through a heat exchanger, and the combustion-supporting air is preheated to 380 °C for use in the muffle rotary pyrolysis furnace and the muffle rotary dezincking furnace. During the heat exchange process, the pyrolysis oil gas temperature gradually decreases and precipitates. The yield of pyrolysis oil is 45%, and the yield of hydrogen-rich combustible gas is 13%. The hydrogen-rich combustible gas is pressurized through a pipeline and introduced into the muffle rotary pyrolysis furnace and the muffle rotary dezincking furnace to be mixed with the combustion-supporting air for combustion, providing heat for the pyrolysis of waste tire pieces and the dezincking reaction of pyrolysis carbon black.

[0036] (3) The high-temperature pyrolysis carbon black discharged from the muffle rotary pyrolysis furnace is added into the muffle rotary dezincking furnace through a heat transfer device for high-temperature roasting and reduction dezincking. The roasting temperature is 1150 °C, and the roasting time is 60 min. Through roasting and reduction, the zinc oxide in the pyrolysis carbon black is reduced to generate zinc vapor, and the zinc vapor is discharged out of the furnace with the high-temperature gas. The temperature of the high-temperature gas is 1030 °C, and the temperature of the dezincked pyrolysis carbon black is 1130 °C. It is discharged into a cooling cylinder through a discharging device for cooling.

[0037] (4) The zinc-containing gas is introduced into an oxidation sedimentation chamber for rough dust removal, and coarse particulate dust is obtained at the bottom. The zinc content in the coarse particulate dust is 0.67%, which does not meet the requirements of zinc element content for blast furnace injection, and it is returned to the muffle rotary dezincking furnace for dezincking treatment again. The zinc-containing gas purified by rough dust removal reacts with excessive air for oxidation reaction, and the metallic zinc vapor is oxidized by the excessive air into high-grade zinc oxide dust. By adjusting the amount of oxidation air introduced, the temperature of the high-temperature zinc-containing flue gas is controlled at 950 °C, and the high-temperature zinc-containing flue gas is introduced into a heat exchanger through a pipeline for temperature reduction.

[0038] (5) After passing through the heat exchanger, the temperature of the high-temperature zinc-containing flue gas is reduced to 170 °C, and zinc oxide products are collected by a bag filter. The zinc oxide grade is 63%. The remaining flue gas is purified by a desulfurization and denitration device and directly discharged after meeting the waste gas emission standards. The heat exchanger generates high-temperature and high-pressure steam for subsequent power generation, and the generated electricity meets the requirements of the entire process flow and no external power needs to be purchased.

[0039] (6) The temperature of the high-temperature dezincified pyrolysis carbon black after being cooled by the cooling cylinder is 150 °C. The dezincified pyrolysis carbon black discharged from the cooling cylinder contains a large amount of waste steel wires, and the waste steel wires need to be removed by a magnetic separator. After removing the waste steel wires, the fixed carbon content of the dezincified pyrolysis carbon black is 79%, the volatile matter content is 3.5%, the ash content is 17.5%, the calorific value is 26.3 MJ / kg, and the zinc element content is less than 0.3%, meeting the quality requirements of blast furnace injection of solid fuel.

[0040] (7) Mix the dezincified pyrolysis carbon black with blast furnace injection bituminous coal, and the mass ratio of the dezincified pyrolysis carbon black is 40%. The mixed material is transported to a medium-speed mill by a belt for crushing. The proportion of the crushed mixed pulverized coal with a particle size less than 200 mesh is 78%. The mixed pulverized coal is transported to the tuyere raceway of the blast furnace through a blowing system for combustion, providing heat and reducing agent for blast furnace smelting.

[0041] Examples 2 - 5

[0042] Examples 2 - 5 provide a method for preparing blast furnace injection fuel by dezincifying waste tire pyrolysis carbon black. Compared with Example 1, the difference lies in changing the pyrolysis temperature and time in step (1). The specific values of the pyrolysis temperature and time corresponding to each example are shown in Table 1:

[0043] Table 1 Pyrolysis temperature and time corresponding to Examples 2 - 5

[0044] Example Cracking temperature (°C) Cracking time (min) Example 2 350 350 Example 3 450 250 Example 4 650 30 Example 5 850 150

[0045] Test the dezincified pyrolysis carbon black prepared in each example, and the results are shown in Table 2:

[0046] Table 2 Properties of the dezincified pyrolysis carbon black prepared in step (5) of Examples 2 - 5

[0047]

[0048] As can be seen from Table 2, the yield of dezincified pyrolytic carbon black prepared in Examples 2 to 5 is between 43.1% and 48.5%, the fixed carbon content is between 78.3% and 79.1%, the volatile content is between 3.1% and 4.9%, the ash content is between 16.8% and 17.9%, the zinc content is between 0.27% and 0.33%, the calorific value is between 25.8 MJ / kg and 26.9 MJ / kg, and the composition of dezincified pyrolytic carbon black meets the requirements of blast furnace injection. The pyrolysis temperature of the muffle rotary pyrolysis furnace has a great influence on the high-molecular organic components in waste tires. As the pyrolysis temperature increases, the organic components decompose more completely, the yield of the residual solid product gradually decreases, at the same time, the volatile content in the obtained pyrolytic carbon black sample decreases, the fixed carbon content gradually increases, and the ash content also slightly increases. The content of zinc element in dezincified pyrolytic carbon black is affected by the composition and properties of pyrolytic carbon black. The higher the ash content of pyrolytic carbon black, the more the residual zinc content. In addition, as the pyrolysis temperature increases, the activity of carbon in pyrolytic carbon black gradually decreases, and the activity of reacting with zinc oxide in the dezincification rotary furnace gradually decreases, resulting in a decrease in the dezincification rate and an increase in the content of residual zinc element in the prepared dezincified pyrolytic carbon black.

[0049] Examples 6 to 13

[0050] Examples 6 to 13 provide a method for preparing blast furnace injection fuel by dezincifying waste tire pyrolytic carbon black. Compared with Example 3, the difference lies in changing the roasting reduction temperature and time of the muffle rotary dezincification furnace in step (3). The specific values of the roasting reduction temperature and time corresponding to each example are shown in Table 3:

[0051] Table 3 Roasting reduction temperature and time of the muffle rotary dezincification furnace corresponding to Examples 6 to 13

[0052] Example Roasting reduction temperature (°C) Roasting reduction time (min) Example 6 1150 80 Example 7 1175 80 Example 8 1200 80 Example 9 1225 80 Example 10 1250 80 Example 11 1200 30 Example 12 1200 120 Example 13 1200 160

[0053] The dezincified pyrolytic carbon black prepared in each example was tested, and the results are shown in Table 4:

[0054] Table 4 Properties of the dezincified pyrolytic carbon black prepared in step (5) of Examples 6 to 13

[0055]

[0056] As can be seen from Table 4, the yield of dezincified pyrolytic carbon black prepared in Examples 6-13 is between 40.3% and 46.2%, the fixed carbon content is between 78.3% and 82.7%, the volatile content is between 1.7% and 4.3%, the ash content is between 15.6% and 18.1%, the zinc content is between 0.19% and 0.33%, and the calorific value is between 25.9 MJ / kg and 27.9 MJ / kg. The composition of dezincified pyrolytic carbon black meets the requirements of blast furnace injection. The zinc element content in dezincified pyrolytic carbon black is mainly affected by the roasting reduction temperature and roasting reduction time. The higher the roasting reduction temperature, the faster the reduction reaction rate of zinc oxide and carbon element in pyrolytic carbon black, and the generated metallic zinc escapes in the form of gas under the roasting temperature condition and is removed. The higher the roasting reduction temperature, the faster the reduction reaction rate of zinc oxide, the faster the escape rate of metallic zinc, the better the dezincification effect, and the lower the corresponding residual zinc content. In addition, the reduction amount of zinc oxide is also affected by the reduction time. The longer the reduction time, the more the reduction amount of zinc oxide, the more the gasification amount and escape amount of generated metallic zinc, and the lower the residual zinc oxide content in dezincified pyrolytic carbon black. The higher the roasting reduction temperature and the longer the roasting reduction time, the lower the volatile content in pyrolytic carbon black. At the same time, the progress of the dezincification reaction causes the ash content to gradually decrease, resulting in a slightly increasing trend of the fixed carbon content with the increase of the roasting temperature. The calorific value of dezincified pyrolytic carbon black also gradually increases with the increase of the roasting temperature and the extension of time.

[0057] The above is only an illustrative embodiment of the present invention, and does not impose any formal or substantial limitations on the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the method of the present invention, several improvements and supplements should also be regarded as the protection scope of the present invention; at the same time, any equivalent changes, modifications, and evolutions made to the above embodiments based on the essential technology of the present invention still belong to the protection scope of the present invention.

Claims

1. A method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis, characterized in that: The steps include: (1) crushing the waste tires into a certain particle size and then loading them into a flame-muffled rotary cracking furnace through a conveying and feeding device for cracking to obtain cracked oil gas and cracked carbon black; (2) The cracked oil and gas are cooled by a heat exchanger to separate the cracked oil and hydrogen-rich combustible gas, and the hydrogen-rich combustible gas is used as fuel for a muffled rotary cracking furnace and a muffled rotary dezincification furnace; (3) The pyrolysis carbon black is added to the flameless rotary dezincification furnace through a heat transport device for high-temperature roasting reduction dezincification to generate zinc-containing coal gas and dezincified pyrolysis carbon black; (4) The zinc-containing coal gas is roughly purified in the oxidation settling chamber, and the coarse particles at the bottom of the settling chamber are returned to the flame-muffle rotary dezincification furnace. The zinc vapor is oxidized into fine zinc oxide particles and enters the heat exchanger with the high-temperature flue gas; (5) The high-temperature zinc-containing flue gas is cooled by a heat exchanger and then enters a bag filter. Zinc oxide products are obtained after being filtered by the bag filter. The remaining flue gas is directly discharged after passing through a purification system to meet waste emission standards; (6) The dezincified pyrolysis carbon black is cooled by a cooling drum, and the waste steel wire contained in the dezincified pyrolysis carbon black after cooling is removed by a magnetic separator; (7) The dezincified cracking carbon black is mixed with the pulverized coal for blast furnace injection and then transported to the pulverizing system for crushing. The crushed mixture is then transported to the vortex zone of the blast furnace tuyere for combustion through the injection system.

2. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The particle size of the waste tires after crushing in step (1) is less than 5 cm.

3. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The operating temperature of the flame-muffle rotary pyrolysis furnace in step (1) is 350° C.-850° C., and the residence time of the waste tire particles in the flame-muffle rotary pyrolysis furnace is 30 min-350 min.

4. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The yield of the cracked oil and gas in step (1) is 40%-70%, the cracked oil and gas temperature is 300°C-800°C, the yield of the cracked carbon black is 30%-60%, and the cracked carbon black temperature is 350°C-850°C.

5. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The high-temperature cracked oil and gas in step (2) is cooled by a heat exchanger, and the cracked oil is condensed and precipitated. The yield of the cracked oil is 30%-50%, and the yield of the remaining hydrogen-rich combustible gas is 10%-20%.

6. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The cooling medium of the high-temperature cracked oil and gas in the heat exchanger in step (2) is combustion air, and the combustion air is preheated to 200°C-600°C by the heat exchanger. The preheated combustion air is used for combustion of hydrogen-rich combustible gas in the combustion chamber of the flame-muffle rotary cracking furnace and the flame-muffle rotary dezincification furnace.

7. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The calcination temperature of the pyrolysis carbon black in the flame-muffle rotary dezincification furnace in step (3) is 1050°C-1300°C, and the calcination time is 30min-160min. The zinc oxide in the pyrolysis carbon black is reduced to generate zinc vapor through calcination reduction, and the zinc vapor is discharged out of the furnace along with the high-temperature coal gas.

8. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The zinc-containing coal gas in step (4) is subjected to rough dust removal in an oxidation settling chamber to obtain coarse particles having a zinc content of 0.5%-3.5%, and then returned to the flame-muffle rotary dezincification furnace for further dezincification treatment; the purified zinc-containing coal gas is subjected to an oxidation reaction with excess air, and the metallic zinc vapor is oxidized into high-grade zinc oxide dust. The temperature of the high-temperature zinc-containing flue gas is controlled to be 800°C-1200°C by adjusting the amount of oxidizing air.

9. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The temperature of the high-temperature zinc-containing flue gas in step (5) is reduced to 150°C-250°C after passing through a heat exchanger, and the zinc oxide product is collected by a bag filter with a zinc oxide grade of 60%-70%. The remaining flue gas is directly discharged after passing through a purification system to meet waste emission standards, and the high-temperature and high-pressure steam generated by the heat exchanger is supplied to external use.

10. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The temperature of the dezincified pyrolysis carbon black after cooling in the cooling drum in step (6) is 150° C.-200° C., and the fixed carbon content of the dezincified pyrolysis carbon black after removing the waste steel wire is greater than 75%, the volatile matter content is less than 5%, the ash content is less than 20%, the calorific value is greater than 24 MJ / kg, and the zinc content is less than 0.5%.

11. The method for preparing blast furnace injection fuel by dezincification of carbon black from waste tire pyrolysis according to claim 1, characterized in that: The types of pulverized coal for blast furnace injection in step (7) include one or more mixtures of lignite, bituminous coal, lean coal, anthracite, semi-coke, coke, and other carbon-containing fuels, and the mass proportion of dezincification cracking in the mixed fuel injected into the blast furnace is 1%-60%.

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