Sintering flue gas heat storage combustion-supporting high furnace gas coupling sintering waste heat power generation device and method

Abstract

The application discloses a sintering flue gas heat storage combustion-supporting blast furnace gas coupling sintering waste heat power generation device, which comprises a sintering machine, a pair of high-temperature heat storage furnaces, a first gas preheater, a power generation mechanism and a flue gas purification mechanism.

Description

Technical Field

[0001] This invention relates to the field of sintering flue gas treatment technology. More specifically, this invention relates to a device and method for generating electricity using sintering flue gas for heat storage and combustion support from blast furnace gas coupled with sintering waste heat. Background Technology

[0002] Sintering is a processing method that provides refined raw materials for blast furnace smelting. The sintering plant mixes various raw materials (concentrates, ore powder, fuel, flux, return ore, and iron-containing production waste, etc.) in a specific ratio, adds water, granulates the mixture, spreads it evenly on a sintering machine, ignites it, and sintersets it with exhaust air to obtain sintered material that meets the requirements. However, the iron ore used for sintering usually contains sulfur, nitrogen, and carbon in the form of compounds and oxyacids. During the sintering process, sulfur, nitrogen, and carbon, existing in elemental or compound form, are usually released as gaseous oxides in the oxidation reaction. This results in the presence of large amounts of harmful gases such as SO2, NOx, and CO in the sintering flue gas, thus polluting the atmospheric environment.

[0003] A large amount of sintering flue gas is generated during the sintering process. This gas is often directly discharged after simple dust removal and SO2 removal. However, the NO content in the sintering flue gas is high. X The sintering machine was vented into the air without any treatment, and the annual operating rate of the sintering machine was high, reaching over 90%, resulting in a large amount of flue gas emissions and causing serious environmental impact.

[0004] With the increasing environmental quality requirements and the need for total emission control in my country, restrictions are being placed on the concentration and emission volume of various pollutants in the flue gas discharged from sintering machines, and corresponding treatment measures will be adopted. Currently, the status quo of sintering flue gas treatment in my country is not optimistic. Most sintering flue gas treatment processes only consider desulfurization / denitrification, failing to address the CO gas contained in the flue gas, which still causes serious environmental pollution. Furthermore, the treatment process cannot recover either the sensible heat or the chemical heat of the CO gas contained in the sintering flue gas, resulting in a significant waste of waste heat.

[0005] Meanwhile, the waste heat generated in the sintering process accounts for approximately 19.3% of the total waste heat per ton of steel. How to effectively recover and utilize this heat has attracted significant attention. Currently, sintering waste heat power generation technology is widely used to reduce energy consumption and improve energy efficiency in the sintering process. The basic principle is as follows: sintered ore is cooled by forced draft in a belt cooler or annular cooler. The cold air blown in from the bottom is preheated as it passes through the hot sintered ore layer, becoming high-temperature waste gas. This high-temperature waste gas is then introduced into the boiler by an induced draft fan, preheating the water inside the boiler to generate steam. The steam drives a turbine to rotate and power a generator. However, in existing technologies, due to the limited hot air temperature of the sintering annular cooler, sintering waste heat can only be used for dual-pressure power generation with low-pressure steam parameters, resulting in very low power generation efficiency. Therefore, how to combine flue gas treatment technology with sintering waste heat power generation technology to achieve the beneficial effects of effectively treating CO gas in sintering flue gas, effectively utilizing the chemical heat of CO gas, and improving power generation efficiency is worthy of serious consideration. Summary of the Invention

[0006] One object of the present invention is to solve at least the above-mentioned problems and to provide at least the advantages that will be described later.

[0007] To achieve these objectives and other advantages according to the present invention, a sintering flue gas heat storage and combustion-supporting blast furnace gas coupled sintering waste heat power generation device is provided, comprising:

[0008] The sintering machine has its exhaust port connected to a boiler blower via a pipe.

[0009] At least one pair of high-temperature regenerators, wherein the hot flow inlet end of the high-temperature regenerator is connected to a first gas preheater via a pipeline, and the cold air outlet end of the first gas preheater alternately supplies preheated blast furnace gas to the pair of high-temperature regenerators via a pipeline, and the air outlet of the boiler blower alternately supplies sintering flue gas to the cold flow inlet end of the pair of high-temperature regenerators via a pipeline.

[0010] The power generation mechanism has its fuel inlet end connected to the cold flow outlet end of the high-temperature regenerative furnace via a pipeline, wherein a pair of cold flow outlet ends of the high-temperature regenerative furnace alternately supply the power generation mechanism with the stored sintering flue gas via a pipeline.

[0011] The flue gas purification mechanism has its flue gas inlet end connected to the flue gas outlet end of the furnace of the power generation mechanism via a pipe;

[0012] The cold air inlet of the first gas preheater is connected to the blast furnace gas supply end through a pipeline, and valves are installed on the pipeline.

[0013] Preferably, the power generation mechanism includes:

[0014] The second gas preheater has its cold air inlet connected to the blast furnace gas supply end via a pipeline.

[0015] The power generation boiler has its fuel inlet end connected to the cold flow outlet end of the high-temperature thermal regenerator via a pipeline, and its cold air outlet end connected to the second gas preheater via a pipeline.

[0016] A steam turbine, the main steam inlet of which is connected to the steam outlet of the power generation boiler via a pipeline, and a generator is connected to the rotor of the steam turbine via a coupling;

[0017] Valves are installed on all of the pipelines.

[0018] Preferably, it also includes:

[0019] The ring cooler has its feed end connected to the discharge end of the sintering machine;

[0020] The sintering waste heat boiler has its flue gas inlet end connected to the high-temperature flue gas outlet end of the annular cooler via a pipeline, its flue gas outlet end connected to the inlet end of the built-in economizer of the power generation boiler via a pipeline, and its steam outlet end connected to the make-up steam inlet end of the steam turbine via a pipeline.

[0021] Valves are installed on all of the pipelines.

[0022] Preferably, the low-temperature flue gas outlet of the annular cooler is connected to the air inlet of the boiler blower via a pipeline, and a valve is provided on the pipeline.

[0023] Preferably, the hot air outlets of a pair of high-temperature regenerative furnaces are connected to the hot air inlet of the first gas preheater via pipes, and the hot air outlet of the first gas preheater is connected to the flue gas inlet of the purification mechanism via pipes, with valves installed on each pipe.

[0024] Preferably, the flue gas outlet of the power generation boiler is connected to the hot air inlet of the second gas preheater via a pipe, and the hot air outlet of the second gas preheater is connected to the flue gas inlet of the purification mechanism via a pipe, with valves installed on both pipes.

[0025] Preferably, the flue gas purification mechanism includes:

[0026] The flue gas purifier has its flue gas inlet end connected to the hot air outlet end of the second gas preheater and the hot air outlet end of the first gas preheater via pipes respectively.

[0027] The exhaust fan has its air inlet connected to the smoke outlet of the flue gas purifier via a pipe.

[0028] The smoke exhaust chimney has its smoke inlet end connected to the air outlet end of the smoke exhaust fan via a pipe;

[0029] The flue gas purifier is a desulfurization and denitrification tower, and valves are installed on the pipelines.

[0030] Preferably, it also includes:

[0031] The dust removal structure has its inlet end connected to the exhaust port of the sintering machine via a pipe;

[0032] The exhaust fan has its air inlet connected to the outlet of the dust removal structure via a pipe, and its air outlet is connected to the air inlet of the boiler blower via pipes.

[0033] The dust removal structure is a bag filter, and valves are installed on the pipelines.

[0034] Preferably, the hot air inlet ends of the first gas preheater and the second gas preheater are connected to the supply end of high-temperature combustion flue gas via pipelines.

[0035] A method for providing a sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in the claim includes the following steps:

[0036] S1. After being preheated, the blast furnace gas alternately enters a pair of high-temperature regenerators, where it releases heat.

[0037] S2. The sintering flue gas discharged from the sintering machine alternately enters the high-temperature regenerator that has been preheated in step S1, and is heated to 600~1200℃ before entering the furnace of the power generation boiler.

[0038] S3. After being preheated, the blast furnace gas enters the furnace of the power generation boiler and mixes with the sintering flue gas for combustion.

[0039] S4. The waste heat of sintered ore is collected by an annular cooler and transferred to the sintering waste heat boiler. The heat of flue gas generated by the sintering waste heat boiler is mixed with the built-in economizer of the power generation boiler and preheats the heating medium of the power generation boiler.

[0040] S5. Combustion of blast furnace gas to heat the working fluid of the power generation boiler to generate main steam, which enters the steam turbine to do work. The steam turbine rotor transfers the mechanical energy generated by the work to the generator and converts it into electrical energy.

[0041] When the sintering waste heat boiler only produces medium-pressure hot water, the tail heating surface of the power generation boiler provides a heat source for the medium-pressure hot water to form superheated steam, which is then used as make-up steam to enter the steam turbine to do work.

[0042] S6. The flue gas from the furnace of the power generation boiler enters the flue gas purification mechanism and is discharged after purification.

[0043] The present invention has at least the following beneficial effects:

[0044] First, this invention uses the heat-storage sintering flue gas as fuel for the power generation boiler—blast furnace gas—to assist combustion, making full use of the physical sensible heat of the sintering flue gas. The CO gas in the sintering flue gas will also be burned in the power generation boiler, so that the chemical heat of the CO gas can also be effectively utilized.

[0045] Secondly, this invention uses the heat-storaged sintering flue gas as combustion aid for blast furnace gas, and together with the sintering waste heat, it provides heat to the power generation mechanism, heating the working fluid to generate high-pressure main steam, which enters the steam turbine and is converted into mechanical energy, and then into electrical energy in the generator. The power generation boiler makes full use of the sintering flue gas and sintering waste heat, thereby improving the power generation efficiency.

[0046] Third, the present invention adopts the method of feeding the flue gas generated by the combustion of the power generation boiler and the unburned sintering flue gas into the second gas preheater from the hot air inlet end, so as to recover and utilize the flue gas residue and save energy for preheating blast furnace gas.

[0047] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the pipeline connection of the power generation device according to one of the technical solutions of the present invention. Detailed Implementation

[0049] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0050] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are all conventional methods, and the reagents and materials described are all commercially available unless otherwise specified. In the description of this invention, the orientation or positional relationship indicated by the terms is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. It does not indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0051] like Figure 1 As shown, the present invention provides a sintering flue gas heat storage and combustion-assisted blast furnace gas coupled sintering waste heat power generation device, comprising:

[0052] The sintering machine 1 has a flue gas outlet connected to a boiler blower 2 via a pipe. The sintering machine 1 can be a ring sintering machine 1, a belt sintering machine 1, or a walking beam sintering machine 1. The boiler blower 2 can be a centrifugal blower or an axial flow blower. The boiler blower 2 draws out the sintering flue gas generated by fuel combustion in the furnace of the sintering machine 1.

[0053] At least one pair of high-temperature regenerators 3 are provided. The hot flow inlet of each high-temperature regenerator 3 is connected to a first gas preheater 4 via a pipeline. The cold air outlet of the first gas preheater 4 is alternately supplied with preheated blast furnace gas to the pair of high-temperature regenerators 3 via a pipeline. The air outlet of the boiler blower 2 is alternately supplied with sintering flue gas to the cold flow inlet of each pair of high-temperature regenerators 3 via a pipeline. The first gas preheater 4 can be a partitioned heat exchanger. After preheating the blast furnace gas, the first gas preheater 4 is alternately supplied with preheated blast furnace gas to the pair of high-temperature regenerators 3 via its cold air outlet and pipeline. The boiler blower 2 is alternately supplied with sintering flue gas discharged from the sintering machine 1 to the pair of high-temperature regenerators 3 via its air outlet and pipeline. The sintering flue gas and the preheated blast furnace gas flow alternately through the pair of high-temperature regenerators 3 in the opposite direction, and the preheated blast furnace gas is used to store heat in the sintering flue gas.

[0054] The power generation unit 5 has its fuel inlet connected to the cold flow outlet of the high-temperature regenerative furnace 3 via a pipeline. The cold flow outlets of the pair of high-temperature regenerative furnaces 3 alternately supply the power generation unit 5 with the heat-stored sintering flue gas. The power generation unit 5 may consist of a power generation boiler 53, a steam turbine 54, and a generator 55. The CO gas in the heat-stored sintering flue gas provides part of the fuel for the power generation unit 5, and the O2 in the sintering flue gas assists the combustion of the fuel in the power generation unit 5. The fuel of the power generation unit 5 may be coal gas, natural gas, or liquefied petroleum gas. After the sintering flue gas is heat-stored, the supply of CO gas and combustion-supporting medium intensifies the combustion of the fuel in the power generation unit 5, thereby effectively utilizing the chemical heat of CO gas in the sintering flue gas.

[0055] The flue gas purification mechanism 6 has its flue gas inlet end connected to the furnace flue gas outlet end of the power generation mechanism 5 through a pipe. The sintering flue gas after the fuel has been heated and combusted vigorously in the furnace of the power generation mechanism 5. The flue gas generated by the combustion is discharged through the flue gas purification mechanism 6, which effectively treats the sintering flue gas and the combustion flue gas of the power generation mechanism 5, and reduces the pollution of the flue gas to the atmospheric environment.

[0056] The cold air inlet of the first gas preheater 4 is connected to the blast furnace gas supply end through a pipeline, and valves are installed on the pipeline. The cold air inlet of the first gas preheater 4 can also be connected to the air supply end, and the hot air inlet of the first gas preheater 4 can be connected to the high-temperature combustion flue gas supply end.

[0057] In the above technical solution, after the blast furnace gas is preheated by the first gas preheater 4, it flows alternately from its cold air outlet to the hot air inlet of a pair of high-temperature regenerators 3 through pipelines. The sintering flue gas discharged from the sintering machine 1 flows alternately to the pair of high-temperature regenerators 3 through the outlet of the boiler blower 2. At one moment, when the preheated blast furnace gas enters the high-temperature regenerator 31 and releases heat to its heat storage body, the sintering flue gas flows in the opposite direction through the high-temperature regenerator 31 and absorbs heat from its heat storage body. At another moment, when the preheated blast furnace gas enters the high-temperature regenerator 32 and releases heat to its heat storage body, the sintering flue gas flows in the opposite direction through the high-temperature regenerator 32 and absorbs heat from its heat storage body. After the sintering flue gas is heated by the alternating circulation of the pair of high-temperature regenerators, it flows to the boiler blower 2. The fuel inlet of the power generation unit 5 is supplied with O2, a combustion-supporting medium in the heat-storing sintering flue gas, which assists in the combustion of fuel in the power generation unit 5, thereby generating a large amount of heat for power generation. The CO gas in the heat-storing sintering flue gas can provide some of the fuel for combustion and heat release in the power generation unit 5, achieving effective utilization of the chemical heat of CO gas in the sintering flue gas. Furthermore, all the heat-storing sintering flue gas enters the power generation unit 5, thus fully utilizing the sensible heat in the sintering flue gas. After fully utilizing the sintering flue gas and fuel, the sintering flue gas after combustion in the furnace of the power generation unit 5, as well as the flue gas generated by the fuel in the power generation unit 5, are purified by the flue gas purification unit 6 before being discharged, reducing the pollution of the flue gas to the atmospheric environment.

[0058] In another technical solution, the power generation mechanism includes:

[0059] The second gas preheater 56 has its cold air inlet end connected to the blast furnace gas supply end through a pipeline. The second gas preheater 56 can be a partition wall heat exchanger. The hot air inlet end of the second gas preheater 56 can be connected to the high-temperature combustion flue gas supply end through a pipeline. The second gas preheater 56 uses the high-temperature combustion flue gas to exchange heat and preheat the blast furnace gas flowing in from its cold air inlet end.

[0060] The power generation boiler 53 has its fuel inlet end connected to the cold flow outlet end of the high-temperature regenerator 3 via a pipeline, and its cold air outlet end connected to the second gas preheater 56 via a pipeline. A pair of high-temperature regenerators 3 alternately supply the heat-stored sintering flue gas from their cold flow outlet ends to the fuel inlet of the power generation boiler 53 furnace. The gas mixes with the blast furnace gas that has been preheated by the second gas preheater 56 and enters the fuel inlet of the power generation boiler 53 furnace from its cold air outlet end. The heat-stored sintering flue gas assists the combustion of the preheated blast furnace gas in the furnace of the power generation boiler 53, and the CO gas in it is burned, realizing the effective utilization of the chemical heat of CO gas. The combustion of blast furnace gas in the furnace of the power generation boiler 53 adopts diffusion combustion.

[0061] The steam turbine 54 has its main steam inlet connected to the steam outlet of the power generation boiler 53 via a pipe. A generator 55 is connected to the rotor of the steam turbine 54 via a coupling. The heat from the combustion of blast furnace gas and sintered flue gas after heat storage in the furnace of the power generation boiler 53 heats the working fluid in the power generation boiler 53 to generate main steam. The main steam enters the steam turbine 54 through the main steam inlet on the steam turbine 54 from the steam outlet of the power generation boiler 53 to do work. The rotor of the steam turbine 54 transmits the mechanical energy generated by doing work to the generator 55 through the coupling and converts it into electrical energy, realizing the transformation from heat → steam, fuel internal energy → steam internal energy → mechanical energy → electrical energy.

[0062] Valves are installed on all of the pipelines.

[0063] In the above technical solution, blast furnace gas preheated by the second gas preheater 56 enters the furnace of the power generation boiler 53 through the fuel inlet. It combines with sintering flue gas stored in the high-temperature regenerator 3 and enters the furnace of the power generation boiler 53 for combustion. The power generation boiler 53 effectively utilizes the sensible heat of the sintering flue gas and also burns combustible gases such as CO in the sintering flue gas, fully utilizing its chemical heat. Furthermore, the O2 and other combustion-supporting media in the sintering flue gas aid the combustion of the blast furnace gas. The power generation boiler 53 fully utilizes the heat from the combustion of the sintering flue gas and blast furnace gas to heat its working fluid, generating main steam that enters the steam turbine 54 and performs work to produce mechanical energy. Through the rotor of the steam turbine 54, the mechanical energy is transferred to the generator 55, which converts it into electrical energy and generates electricity. Specifically, the power generation boiler 53 converts the internal energy of the fuel into the internal energy of the steam, the steam turbine 54 converts the internal energy of the steam into mechanical energy, and the generator 55 converts the mechanical energy into electrical energy.

[0064] Another technical solution also includes:

[0065] The ring cooler 51 has its feed end connected to the discharge end of the sintering machine 1. The ring cooler 51 uses cold air to transfer the sintered ore from the sintering machine 1 to the ring cooler 51 for cooling, and the waste heat of the sintered ore is exchanged to form hot waste gas.

[0066] The sintering waste heat boiler 52 has its flue gas inlet connected to the high-temperature flue gas outlet of the annular cooler 51 via a pipeline. The flue gas outlet of the sintering waste heat boiler 52 is connected to the inlet of the built-in economizer of the power generation boiler 53 via a pipeline. The steam outlet of the sintering waste heat boiler 52 is connected to the supplementary steam inlet of the steam turbine 54 via a pipeline. The hot waste gas generated by the annular cooler 51 enters the sintering waste heat boiler 52 from its flue gas inlet through its high-temperature flue gas outlet, preheating the sintering waste heat boiler 52. This preheated gas then combines with the combustion flue gas from the sintering waste heat boiler 52 before entering the power generation boiler 53. The built-in economizer of the power generation boiler 53 absorbs the heat from the flue gas to preheat the power generation boiler 53. The sintering waste heat boiler 52 then... The waste heat from ore sintering is fully utilized; the working fluid of the sintering waste heat boiler 52 and the built-in economizer of the power generation boiler 53 are mixed together to provide preheating heat for the working fluid of the power generation boiler 53. The sintering waste heat boiler 52 is equivalent to an external economizer of the power generation boiler 53 with sintering waste heat as the heat source. When the sintering preheating boiler only produces medium-pressure hot water, the tail heating surface of the power generation boiler 53 provides a heat source for the medium-pressure hot water to form superheated steam. The superheated steam is used as makeup steam and enters the steam turbine 54 through the steam inlet of the steam turbine 54 to do work. At this time, the sintering waste heat boiler 52 needs to add a medium-pressure feedwater extraction steam recovery system, and the number of extraction steam recovery stages is less than the number of extraction steam recovery stages of the feedwater of the power generation boiler 53.

[0067] Valves are installed on all of the pipelines.

[0068] In the above technical solution, the annular cooler 51 exchanges the waste heat of sintered ore with cold air and generates hot waste gas. The sintering waste heat boiler 52 makes full use of the sintering waste heat for preheating. Its working fluid is mixed with the built-in economizer of the power generation boiler 53 to provide preheating heat for the working fluid of the power generation boiler 53. The sintering waste heat boiler 52 is equivalent to an external economizer of the power generation boiler 53 with sintering waste heat as the heat source. The setting of the annular cooler 51 and the sintering waste heat boiler 52 enables the waste heat of sintered ore to be fully utilized.

[0069] In another technical solution, the low-temperature flue gas outlet of the annular cooler 51 is connected to the air inlet of the boiler blower 2 via a pipe. A valve is installed on the pipe. The low-temperature flue gas generated by the cold air heat exchange of the annular cooler 51 flows into the boiler blower 2, and then enters the high-temperature regenerator 3 for heat storage. The low-temperature flue gas contains the combustion-supporting medium O2. Therefore, the low-temperature flue gas from the annular cooler 51 can also assist the combustion of blast furnace gas. When the sintering machine 1 stops working, the cold air or the low-temperature flue gas generated by heat exchange in the annular cooler 51 can be used to replace the sintering flue gas to enter the high-temperature regenerator 3 for heat storage, thereby assisting the combustion of blast furnace gas entering the power generation boiler 53.

[0070] In another technical solution, the hot flow outlet of a pair of high-temperature regenerators 3 is connected to the hot air inlet of the first gas preheater 4 via a pipeline. The hot air outlet of the first gas preheater 4 is connected to the flue gas inlet of the purification mechanism via a pipeline. Valves are installed on the pipelines. After the blast furnace gas releases heat to the high-temperature regenerators 3, it flows out from the hot flow outlet of the high-temperature regenerators 3 and enters the hot air inlet of the first gas preheater 4 through the pipeline. It can exchange heat with the blast furnace gas entering from the cold air inlet of the first gas preheater 4 to recover residual heat. The low-temperature combustion flue gas generated after the high-temperature combustion flue gas exchanges heat enters the flue gas purification mechanism 6 from the hot air outlet of the second gas preheater 56 for purification. The first gas preheater 4 recovers the waste heat of the flue gas and provides some heat for the preheating of the blast furnace gas, realizing the effective recovery and utilization of the waste heat of the flue gas.

[0071] In another technical solution, the flue gas outlet of the power generation boiler 53 is connected to the hot air inlet of the second gas preheater 56 via a pipeline, and the hot air outlet of the second gas preheater 56 is connected to the flue gas inlet of the purification mechanism via a pipeline. Valves are provided on the pipelines. The flue gas generated by the combustion of the power generation boiler 53, as well as the sintering flue gas that has not participated in combustion after heat storage, is discharged through the flue gas outlet of the power generation boiler 53 and enters the hot air inlet of the second gas preheater 56 through a pipeline to exchange heat with the blast furnace gas entering from the cold air inlet of the second gas preheater 56 to recover residual heat. The low-temperature combustion flue gas generated after the high-temperature combustion flue gas is heat-exchanged enters the purification mechanism from the hot air outlet of the second gas preheater 56 for purification. The second gas preheater 56 recovers the waste heat of the flue gas and provides some heat for the preheating of the blast furnace gas, thereby realizing the effective recovery and utilization of waste heat of the flue gas.

[0072] In another technical solution, the flue gas purification mechanism 6 includes:

[0073] The flue gas purifier 61 has its flue gas inlet end connected to the hot air outlet end of the second gas preheater 56 and the hot air outlet end of the first gas preheater 4 via pipes. The flue gas purifier 61 can be a desulfurization and denitrification tower or a mixed flue gas SCR denitrification tower. The combustion flue gas generated from the power generation boiler 53 and discharged through the hot air outlet of the second gas preheater 56 is mixed with the low temperature flue gas discharged from the hot air outlet end of the first gas preheater 4 and then enters the flue gas purifier 61 for purification before being discharged. The flue gas purifier 61 purifies the combustion flue gas and sintering flue gas, and the discharged gas does not contain pollutants such as nitrate and sulfur.

[0074] The exhaust fan 62 has its air inlet connected to the smoke outlet of the flue gas purifier 61 via a pipe.

[0075] The smoke exhaust chimney 63 has its smoke inlet end connected to the air outlet end of the smoke exhaust fan 62 via a pipe;

[0076] The flue gas purifier 61 is a desulfurization and denitrification tower, and valves are installed on the pipelines.

[0077] In the above technical solution, the flue gas purifier 61 is used to denitrify and desulfurize the combustion flue gas generated by the power generation boiler 53 and discharged through the hot air outlet of the second gas preheater 56, as well as the low-temperature flue gas discharged from the hot air outlet of the first gas preheater 4, and then discharge it into the atmosphere or water through the exhaust fan 62 and the exhaust chimney 63.

[0078] Another technical solution also includes:

[0079] The dust removal structure 7 has its inlet end connected to the exhaust port of the sintering machine 1 through a pipe. The dust removal structure 7 can be an electrostatic precipitator or a bag filter. The dust removal structure 7 removes dust from the sintering flue gas discharged from the exhaust port of the sintering machine 1, thereby reducing the impact of dust on the performance of equipment in subsequent processes.

[0080] The exhaust fan 8 has its air inlet connected to the outlet of the dust removal structure 7 via a pipe, and its air outlet connected to the air inlet of the boiler blower 2 via pipes. The exhaust fan 8 connects the sintering machine 1 and the boiler blower 2. The exhaust fan 8 draws air from the exhaust port of the sintering machine 1 to generate negative pressure, so that the sintering material surface is in full contact with the ignited flame, and the solid fuel in the sintering material is fully burned. At the same time, the various flues generated during the sintering process are discharged through the exhaust port.

[0081] The dust removal structure 7 is a bag filter, and valves are installed on the pipeline. The bag filter has a simple structure, is flexible in use, and has high dust removal efficiency.

[0082] In the above technical solution, the sintering flue gas generated by the sintering machine 1 enters the dust removal structure 7 through the flue gas outlet. After effectively removing the dust from the sintering flue gas, the exhaust fan 8 provides negative pressure for the solid combustion in the sintering material and discharges the dust-removed sintering flue gas into the boiler blower 2.

[0083] In another technical solution, the hot air inlet ends of the first gas preheater 4 and the second gas preheater 56 are connected to the supply end of high-temperature combustion flue gas through pipelines. The high-temperature combustion flue gas is the blast furnace gas that is preheated to a certain temperature before entering the high-temperature heat storage furnace 3 or the power generation boiler 53 by the heat dissipation fins inside the first gas preheater 4 and the second gas preheater 56. This can effectively improve the heat exchange performance of the high-temperature heat storage furnace 3 or the power generation boiler 53 and reduce energy consumption.

[0084] A method for providing a blast furnace gas coupled sintering waste heat power generation device based on the aforementioned sintering flue gas heat storage and combustion-supporting blast furnace gas includes the following steps:

[0085] S1. After being preheated, the blast furnace gas alternately enters a pair of high-temperature regenerators 3 and releases heat in the high-temperature regenerators 3. After being preheated by the first gas preheater 4, the blast furnace gas alternately enters a pair of high-temperature regenerators 3 and releases heat to its heat storage body in the high-temperature regenerators 3 to prepare for the heat storage of sintering flue gas.

[0086] S2. The sintering flue gas discharged from the sintering machine 1 alternately enters the high-temperature regenerator 3, which has been preheated in step S1, and is heated to 600~1200℃ before entering the furnace of the power generation boiler 53. The sintering flue gas discharged from the sintering machine 1 is filtered and vented by the dust removal structure 7 and the exhaust fan 8 before entering the boiler blower 2. The boiler blower 2 alternately enters the high-temperature regenerator 3, which has been preheated in step S1, to alternately heat the sintering flue gas. When the temperature is heated to 600~1200℃, it enters the furnace of the power generation boiler 53.

[0087] S3. After preheating, the blast furnace gas enters the furnace of the power generation boiler 53 and mixes with the sintering flue gas for combustion. The heat-storage sintering flue gas assists the combustion of the blast furnace gas entering the furnace of the power generation boiler 53. The combustible gases such as CO in the sintering flue gas are also burned in the furnace, making full use of the physical sensible heat of the sintering flue gas and the chemical heat of CO gas.

[0088] S4. The waste heat of sintered ore is collected by the ring cooler 51 and transferred to the sintering waste heat boiler 52. The heat of flue gas generated by the sintering waste heat boiler 52 is mixed with the built-in economizer of the power generation boiler 53 and preheats the heating medium of the power generation boiler 53. The ring cooler 51 collects the waste heat of sintered ore through heat exchange and transfers it to the sintering waste heat boiler 52 for preheating. The sintering waste heat boiler 52 preheats the power generation boiler 53, so that the waste heat of sintering can be fully utilized and the amount of blast furnace gas used can be saved.

[0089] S5. Combustion of blast furnace gas to heat the working fluid of power generation boiler 53 to generate main steam, which enters steam turbine 54 to do work. The rotor of steam turbine 54 transfers the mechanical energy generated by the work to generator 55 and converts it into electrical energy. Combustion of blast furnace gas to heat power generation boiler 53 to generate high-pressure main steam. After the main steam reaches certain specified parameters, it enters steam turbine 54 to do work and generate mechanical energy, which is transferred to generator 55 and converted into electrical energy by generator 55 to realize power generation.

[0090] When the sintering waste heat boiler 52 only produces medium-pressure hot water, the tail heating surface of the power generation boiler 53 provides a heat source for the medium-pressure hot water to form superheated steam, and the superheated steam enters the steam turbine 54 as makeup steam to do work.

[0091] S6. The flue gas after combustion in the furnace of the power generation boiler 53 enters the flue gas purification mechanism 6 and is discharged after purification. The flue gas after combustion is desulfurized and denitrified by the flue gas purifier 61 in the flue gas purification mechanism 6, and then discharged into the atmosphere through the exhaust fan 62 and the exhaust chimney 63. The low-temperature flue gas after heat exchange in the first gas preheater 4 also needs to be purified before being discharged.

[0092] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A sintering flue gas heat storage and combustion aid blast furnace gas coupled with sintering waste heat power generation device, characterized in that, include: The sintering machine has its exhaust port connected to a boiler blower via a pipe. At least one pair of high-temperature regenerators, wherein the hot flow inlet end of the high-temperature regenerator is connected to a first gas preheater via a pipeline, and the cold air outlet end of the first gas preheater alternately supplies preheated blast furnace gas to the pair of high-temperature regenerators via a pipeline, and the air outlet of the boiler blower alternately supplies sintering flue gas to the cold flow inlet end of the pair of high-temperature regenerators via a pipeline. The power generation mechanism has its fuel inlet end connected to the cold flow outlet end of the high-temperature regenerative furnace via a pipeline, wherein a pair of cold flow outlet ends of the high-temperature regenerative furnace alternately supply the power generation mechanism with the stored sintering flue gas via a pipeline. The flue gas purification mechanism has its flue gas inlet end connected to the flue gas outlet end of the furnace of the power generation mechanism via a pipe; The cold air inlet of the first gas preheater is connected to the blast furnace gas supply end through a pipeline, and valves are installed on the pipeline.

2. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 1, characterized in that, The power generation mechanism includes: The second gas preheater has its cold air inlet connected to the blast furnace gas supply end via a pipeline. The power generation boiler has its fuel inlet end connected to the cold flow outlet end of the high-temperature thermal regenerator via a pipeline, and its cold air outlet end connected to the second gas preheater via a pipeline. A steam turbine, the main steam inlet of which is connected to the steam outlet of the power generation boiler via a pipeline, and a generator is connected to the rotor of the steam turbine via a coupling; Valves are installed on all of the pipelines.

3. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 2, characterized in that, Also includes: The ring cooler has its feed end connected to the discharge end of the sintering machine; The sintering waste heat boiler has its flue gas inlet end connected to the high-temperature flue gas outlet end of the annular cooler via a pipeline, its flue gas outlet end connected to the inlet end of the built-in economizer of the power generation boiler via a pipeline, and its steam outlet end connected to the make-up steam inlet end of the steam turbine via a pipeline. Valves are installed on all of the pipelines.

4. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 3, characterized in that, The low-temperature flue gas outlet of the annular cooler is connected to the air inlet of the boiler blower via a pipeline, and a valve is installed on the pipeline.

5. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 1, characterized in that, The hot air outlet of a pair of high-temperature regenerative furnaces is connected to the hot air inlet of the first gas preheater via a pipe, and the hot air outlet of the first gas preheater is connected to the flue gas inlet of the purification mechanism via a pipe. Valves are provided on the pipes.

6. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 2, characterized in that, The flue gas outlet of the power generation boiler is connected to the hot air inlet of the second gas preheater via a pipe, and the hot air outlet of the second gas preheater is connected to the flue gas inlet of the purification mechanism via a pipe. Valves are provided on the pipes.

7. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 2, characterized in that, The flue gas purification mechanism includes: The flue gas purifier has its flue gas inlet end connected to the hot air outlet end of the second gas preheater and the hot air outlet end of the first gas preheater via pipes respectively. The exhaust fan has its air inlet connected to the smoke outlet of the flue gas purifier via a pipe. The smoke exhaust chimney has its smoke inlet end connected to the air outlet end of the smoke exhaust fan via a pipe; The flue gas purifier is a desulfurization and denitrification tower, and valves are installed on the pipelines.

8. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 1, characterized in that, Also includes: The dust removal structure has its inlet end connected to the exhaust port of the sintering machine via a pipe; The exhaust fan has its air inlet connected to the outlet of the dust removal structure via a pipe, and its air outlet is connected to the air inlet of the boiler blower via pipes. The dust removal structure is a bag filter, and valves are installed on the pipelines.

9. The sintering flue gas heat storage and combustion-supporting blast furnace gas coupled with sintering waste heat power generation device as described in claim 2, characterized in that, The hot air inlet ends of the first gas preheater and the second gas preheater are connected to the supply end of high-temperature combustion flue gas through pipelines.

10. A method for a sintering flue gas heat storage and combustion-assisted blast furnace gas coupled with sintering waste heat power generation device as described in claim 3, comprising the following steps: S1. After being preheated, the blast furnace gas alternately enters a pair of high-temperature regenerators, where it releases heat. S2. The sintering flue gas discharged from the sintering machine alternately enters the high-temperature regenerator that has been preheated in step S1, and is heated to 600~1200℃ before entering the furnace of the power generation boiler. S3. After being preheated, the blast furnace gas enters the furnace of the power generation boiler and mixes with the sintering flue gas for combustion. S4. The waste heat of sintered ore is collected by an annular cooler and transferred to the sintering waste heat boiler. The heat of flue gas generated by the sintering waste heat boiler is mixed with the built-in economizer of the power generation boiler and preheats the heating medium of the power generation boiler. S5. Combustion of blast furnace gas to heat the working fluid of the power generation boiler to generate main steam, which enters the steam turbine to do work. The steam turbine rotor transfers the mechanical energy generated by the work to the generator and converts it into electrical energy. When the sintering waste heat boiler only produces medium-pressure hot water, the tail heating surface of the power generation boiler provides a heat source for the medium-pressure hot water to form superheated steam, which is then used as make-up steam to enter the steam turbine to do work. S6. The flue gas from the furnace of the power generation boiler enters the flue gas purification mechanism and is discharged after purification.

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