A system and method for full recycling of sintering ring cooling waste flue gas

Abstract

The present application relates to a kind of sintering ring cold waste flue gas full recycling system and method, belong to sintering ring cold waste gas treatment system and method technical field of iron and steel industry.The technical scheme of the present application is: ring cooling machine (8) is respectively connected with flue gas upgrading device (1) and waste heat generator set (2) on the upper part, flue gas upgrading device (1) is connected steam pipe network (5) and desalted water pipe network (6), flue gas upgrading device (1) is connected sintering machine (7) by oxygen-rich waste gas pipeline (3), oxygen-rich waste gas pipeline (4) and steam pipe network (5).The beneficial effects of the present application are: realize the efficient recycling of sintering ring cold waste heat resource, to reduce sintering solid fuel consumption, save energy cost, reduce pollutant emission, improve the purpose of sinter quality.

Description

Technical Field

[0001] This invention relates to a system and method for the complete recovery and utilization of waste heat from sintering ring cooling, belonging to the technical field of sintering ring cooling waste gas treatment systems and methods in the steel industry. Background Technology

[0002] Statistics show that solid fuel consumption in sintering accounts for about 75%-80% of the energy consumption in the ironmaking process. For every 1°C increase in the temperature of the sintering mixture, solid fuel consumption can be reduced by about 0.12 kg of standard coal. The waste heat dissipated during the cooling process of the sinter produced by the blower-type ring cooler accounts for about 30% of the total heat of the sintering process. Therefore, increasing the temperature of the mixture and recovering the waste heat of the ring cooler are particularly important for reducing the energy consumption of the sintering process.

[0003] Many enterprises have built sintering annular cooling waste heat power generation systems to recover and utilize the heat from the high-temperature waste flue gas. However, for medium- and low-temperature flue gas (50-300℃), the heat is insufficient, and direct use in boiler heat exchange for generator sets can only produce low-parameter steam, resulting in low efficiency and high utilization costs. Some enterprises use the medium- and low-temperature waste flue gas from the annular cooling system for hot air sintering or directly return it to the sintering material surface through a flue gas recirculation system to utilize the sensible heat of the medium- and low-temperature waste flue gas and eliminate environmental pollution caused by dust-laden flue gas emissions into the air. However, because the flue gas temperature is much higher than the air temperature, the flue gas volume expansion leads to a significant decrease in oxygen content, which is not conducive to fuel combustion in the sintering mixture and affects the quality of sintered ore products.

[0004] Currently, metallurgical enterprises use steam heating to increase the temperature of sintering mixtures. The steam source is usually saturated steam generated by converters, heating furnaces, etc., which is transported to the sintering production line through pipelines. This method suffers from significant heat loss during the transportation of saturated steam due to the long pipelines and the fact that about 20-40% of the steam condenses and is discharged from the steam trap. Alternatively, enterprises that have built sintering waste heat power generation units use low-parameter steam generated by waste heat boilers to heat the mixtures. While this avoids the losses caused by long pipelines, it reduces the power generation of the sintering waste heat power generation units.

[0005] In summary, to reduce sintering solid fuel consumption, save energy costs, reduce pollutant emissions, and improve the quality of sintered ore, it is necessary to design a more efficient sintering ring cooling waste heat and flue gas recovery and utilization system to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a system and method for the complete recovery and utilization of waste heat from sintering ring coolers. This involves using the high-temperature waste heat from the ring cooler for power generation in a waste heat generator set, using the low-temperature waste heat from the ring cooler as a cooling medium in the intermediate temperature section of the ring cooler, and subjecting the intermediate-temperature waste heat from the ring cooler to a series of upgrading treatments to generate oxygen-enriched waste gas, oxygen-enriched steam-enriched waste gas, and steam. This achieves efficient and complete recovery and utilization of the waste heat from sintering ring coolers. Furthermore, the generated oxygen-enriched waste gas is used for oxygen-enriched hot air sintering, the generated oxygen-enriched steam-enriched waste gas is used for oxygen-enriched steam-enriched sintering at the material surface, and the generated steam is used to increase the temperature of the sintering mixture and as a steam source for the oxygen-enriched steam-enriched waste gas. This achieves efficient recovery and utilization of waste heat resources from sintering ring coolers, thereby reducing sintering solid fuel consumption, saving energy costs, reducing pollutant emissions, and improving the quality of sintered ore, effectively solving the aforementioned problems existing in the background art.

[0007] The technical solution of this invention is: a system for the full recovery and utilization of waste heat and flue gas from sintering ring coolers, comprising a flue gas upgrading device, a waste heat generator set, an oxygen-enriched waste gas pipeline, an oxygen-enriched steam waste gas pipeline, a steam network, a demineralized water network, a sintering machine, and a ring cooler. The upper part of the ring cooler is connected to the flue gas upgrading device and the waste heat generator set, respectively. The flue gas upgrading device is connected to the steam network and the demineralized water network. The flue gas upgrading device is connected to the sintering machine through the oxygen-enriched waste gas pipeline, the oxygen-enriched steam waste gas pipeline, and the steam network.

[0008] The upper part of the annular cooler is divided into a high-temperature section, a medium-temperature section, and a low-temperature section according to the direction of operation. A high-temperature section hood, a medium-temperature section hood, and a low-temperature section hood are respectively installed on the upper part of each section of the annular cooler. The top of the high-temperature section hood is connected to the waste heat generator unit through an air supply pipe. The top air outlet of the low-temperature section hood is connected to the bottom air inlet of the medium-temperature section through an air supply pipe. The top air outlet of the medium-temperature section hood is connected to the flue gas inlet of the flue gas upgrading device through an air supply pipe.

[0009] The flue gas inlet of the flue gas upgrading device is installed at the bottom of the device, and an electric butterfly valve is installed at the flue gas inlet. The medium-temperature waste flue gas collected from the medium-temperature section hood enters the flue gas upgrading device through the flue gas inlet. The waste flue gas will pass through the oxygen-enriched heating zone, the steam generation zone and the diversion steam boosting zone from bottom to top, and finally produce oxygen-enriched hot waste gas, oxygen-enriched steam-enriched hot waste gas and steam.

[0010] The oxygen-enriched heating zone is equipped with an oxygen-enriched burner, and there are more than one oxygen-enriched burner. Each oxygen-enriched burner is individually equipped with a combustible gas pipeline and an oxygen pipeline.

[0011] The steam generation zone is equipped with a steam evaporator and a water preheater from bottom to top, and a steam bunker is installed externally. The inlet of the water preheater is connected to the demineralized water pipeline network, and the outlet is connected to the hot water inlet of the steam bunker. The hot water inlet of the steam evaporator is connected to the hot water outlet of the steam bunker, and the steam outlet of the steam generator is connected to the steam inlet of the steam bunker. The steam bunker is equipped with two steam outlets, one of which is connected to the steam inlet of the steam injection device in the diversion and steam boosting zone, and the other outlet is connected to the steam pipeline network.

[0012] The top of the diversion and steam boosting zone is equipped with an electric diversion baffle, which divides the diversion and steam boosting zone into two independent chambers. The top of one chamber is directly connected to the oxygen-enriched hot exhaust gas outlet of the flue gas upgrading device; the other chamber is equipped with a steam injection device, the steam inlet of which is connected to a steam outlet of a steam package through a steam pipe, and the top of this chamber is connected to the oxygen-enriched and steam-enriched hot exhaust gas outlet of the flue gas upgrading device; the electric diversion baffle adjusts the air intake of the two chambers by swinging left and right.

[0013] The sintering machine is equipped with a sealing cover on its upper part, and the sealing cover is installed in the 3 / 10 to 8 / 10 material surface area between the sintering ignition point and the sintering endpoint; the sintering machine is equipped with a heat-resistant combustion-supporting fan and a mixing tank.

[0014] The oxygen-enriched hot exhaust gas outlet of the flue gas upgrading device is connected to the air inlet of the heat-resistant combustion fan of the sintering machine through an oxygen-enriched exhaust gas pipeline; the oxygen-enriched steam-enriched hot exhaust gas outlet of the flue gas upgrading device is connected to the sealing cover through an oxygen-enriched steam-enriched exhaust gas pipeline; the steam pipeline inlet is connected to another steam outlet of the steam package of the flue gas upgrading device, and the steam pipeline outlet is connected to the mixing tank of the sintering machine.

[0015] A method for the complete recovery and utilization of waste heat flue gas from sintering ring cooling includes the following steps: (1) Use the high-temperature waste flue gas from the ring-cooled generator set for power generation; (2) The low-temperature waste flue gas of the ring cooling is used as the cooling medium of the ring cooling medium temperature section, and the generated ring cooling medium temperature waste flue gas is obtained by oxygen-enriched supplementary heat combustion to obtain high-temperature oxygen-enriched waste flue gas. (3) Use hot water to exchange heat with high-temperature oxygen-enriched waste flue gas to obtain steam and medium-temperature oxygen-enriched waste flue gas. (4) Hot water and oxygen-enriched waste gas are obtained by exchanging heat between cold water and medium-temperature oxygen-enriched waste gas. (5) Use steam to increase the steam content of oxygen-rich hot waste gas to obtain oxygen-rich steam-rich hot waste gas. (6) The generated oxygen-enriched hot waste gas is used as combustion air for oxygen-enriched hot air sintering. (7) The generated oxygen-rich and steam-rich hot exhaust gas is sent to the sealing cover of the sintering machine for oxygen-rich and steam-rich sintering. (8) The generated steam is sent to the sintering mixing tank to increase the temperature of the mixture.

[0016] In step (1), the temperature of the annularly cooled high-temperature waste flue gas is not lower than 350°C, preferably 400-550°C, and more preferably 450-500°C. In step (2), the temperature of the annularly cooled low-temperature waste gas is not higher than 100℃, preferably 60-90℃, and more preferably 50-80℃; the temperature of the annularly cooled medium-temperature waste gas is not lower than 100℃, preferably 120-250℃, and more preferably 160-230℃; the temperature of the high-temperature oxygen-enriched waste gas is not lower than 200℃, preferably 230-300℃, and more preferably 230-280℃; the oxygen content of the high-temperature oxygen-enriched waste gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%. In step (3), the temperature of the medium-temperature oxygen-enriched waste gas is not higher than 240℃, preferably 190-240℃, and more preferably 210-225℃; the oxygen content of the medium-temperature oxygen-enriched waste gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%; the steam temperature is not higher than 180℃, preferably 130-180℃, and more preferably 150-165℃. In step (4), the temperature of the oxygen-enriched thermal exhaust gas is not higher than 170℃, preferably 120-170℃, and more preferably 140-155℃; the oxygen content of the oxygen-enriched thermal exhaust gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%. In step (5), the temperature of the oxygen-enriched and steam-enriched waste gas is not higher than 180℃, preferably 130-170℃, and more preferably 140-160℃; the oxygen content of the oxygen-enriched and steam-enriched waste gas is not less than 20%, preferably 20-23%, and more preferably 21-22%; the steam concentration of the oxygen-enriched and steam-enriched waste gas is not less than 2wt%, preferably 3-5wt%, and more preferably 4-4.5wt%. In step (5), the proportion of oxygen-enriched thermal waste gas used for steam boosting treatment is 40-60% of the total amount of oxygen-enriched thermal waste gas, preferably 48-58%, and more preferably 52-55%.

[0017] The beneficial effects of this invention are as follows: by using the high-temperature waste heat flue gas from the annular cooling system for power generation in a waste heat generator set, using the low-temperature waste heat flue gas from the annular cooling system as a cooling medium in the intermediate temperature section of the annular cooling system, and subjecting the intermediate temperature waste heat flue gas from the annular cooling system to a series of upgrading treatments to generate oxygen-enriched hot waste gas, oxygen-enriched steam-enriched hot waste gas, and steam, the efficient and complete recovery and utilization of the waste heat flue gas from the sintering annular cooling system is achieved. Furthermore, the generated oxygen-enriched hot waste gas is used for oxygen-enriched hot air sintering, the generated oxygen-enriched steam-enriched hot waste gas is used for oxygen-enriched steam-enriched sintering on the material surface, and the generated steam is used to increase the temperature of the sintering mixture and as a steam source for the oxygen-enriched steam-enriched hot waste gas. This achieves the efficient recovery and utilization of the waste heat resources from the sintering annular cooling system, thereby reducing the solid fuel consumption of sintering, saving energy costs, reducing pollutant emissions, and improving the quality of sintered ore. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the flue gas upgrading device of the present invention; In the diagram: 1. Flue gas upgrading device; 101. Flue gas inlet; 102. Electric butterfly valve; 103. Oxygen-enriched heating zone; 104. Steam generation zone; 105. Diversion and steam boosting zone; 106. Oxygen-enriched burner; 107. Combustible gas pipeline; 108. Oxygen pipeline; 109. Steam evaporator; 110. Water preheater; 111. Steam drum; 112. Electric diversion baffle; 113. Oxygen-enriched hot waste gas outlet; 114. Oxygen-enriched steam-enriched hot waste gas outlet; 115. Steam injection device; 2. Waste heat generator set; 3. Oxygen-enriched waste gas pipeline; 4. Steam pipeline network; 5. Demineralized water pipeline network; 6. Sintering machine; 7. Heat-resistant combustion fan; 701. Mixing tank; 702. Sealing cover; 703. Circular cooler; 8. High-temperature section; 801. Medium-temperature section; 802. Low-temperature section; 803. High-temperature section hood; 804. Medium-temperature section hood; 805. Low-temperature section hood; 806. Detailed Implementation

[0019] To make the purpose, technical solutions, and advantages of the invention's embodiments clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only a small part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0020] A system for the complete recovery and utilization of waste heat and flue gas from sintering ring coolers includes a flue gas upgrading device 1, a waste heat generator set 2, an oxygen-enriched waste gas pipeline 3, an oxygen-enriched steam waste gas pipeline 4, a steam pipeline network 5, a demineralized water pipeline network 6, a sintering machine 7, and an ring cooler 8. The upper part of the ring cooler 8 is connected to the flue gas upgrading device 1 and the waste heat generator set 2, respectively. The flue gas upgrading device 1 is connected to the steam pipeline network 5 and the demineralized water pipeline network 6. The flue gas upgrading device 1 is connected to the sintering machine 7 through the oxygen-enriched waste gas pipeline 3, the oxygen-enriched steam waste gas pipeline 4, and the steam pipeline network 5.

[0021] The upper part of the annular cooler 8 is divided into a high-temperature section 801, a medium-temperature section 802, and a low-temperature section 803 according to the operating direction. A high-temperature section hood 804, a medium-temperature section hood 805, and a low-temperature section hood 806 are respectively installed on the upper part of each section of the annular cooler. The top of the high-temperature section hood 804 is connected to the waste heat generator set 2 through an air supply pipe. The top air outlet of the low-temperature section hood 806 is connected to the bottom air inlet of the medium-temperature section 805 through an air supply pipe. The top air outlet of the medium-temperature section hood 805 is connected to the flue gas inlet 101 of the flue gas upgrading device 1 through an air supply pipe.

[0022] The flue gas inlet 101 of the flue gas upgrading device 1 is installed at the bottom of the device, and an electric butterfly valve 102 is installed at the flue gas inlet 101. The medium-temperature waste flue gas collected from the medium-temperature section hood 805 enters the flue gas upgrading device 1 through the flue gas inlet 101. The waste flue gas will pass through the oxygen-enriched heating zone 103, the steam generation zone 104 and the diversion steam boosting zone 105 from bottom to top, and finally generate oxygen-enriched hot waste gas, oxygen-enriched steam-enriched hot waste gas and steam.

[0023] The oxygen-enriched heating zone 103 is equipped with an oxygen-enriched burner 106. There is one or more oxygen-enriched burners 106, and each oxygen-enriched burner is individually equipped with a combustible gas pipeline 107 and an oxygen pipeline 108.

[0024] The steam generation zone 104 is equipped with a steam evaporator 109 and a water preheater 110 arranged from bottom to top, and a steam package 111 is arranged outside. The inlet of the water preheater 110 is connected to the demineralized water pipeline network 6, and the outlet is connected to the hot water inlet of the steam package 111. The hot water inlet of the steam evaporator 109 is connected to the hot water outlet of the steam package 111, and the steam outlet of the steam generator 109 is connected to the steam inlet of the steam package 111. The steam package 111 is equipped with two steam outlets, one of which is connected to the steam inlet of the steam injection device 115 of the steam diversion and steam boosting zone 105, and the other outlet is connected to the steam pipeline network 5.

[0025] The top of the diversion and steam boosting zone 105 is equipped with an electric diversion baffle 112, which divides the diversion and steam boosting zone 105 into two independent chambers. The top of one chamber is directly connected to the oxygen-enriched hot exhaust gas outlet 113 of the flue gas upgrading device 1. The other chamber is equipped with a steam injection device 115. The steam inlet of the steam injection device 115 is connected to a steam outlet of the steam package 111 through a steam pipe. The top of this chamber is connected to the oxygen-enriched and steam-enriched hot exhaust gas outlet 114 of the flue gas upgrading device 1. The electric diversion baffle 112 adjusts the air intake of the two chambers by swinging left and right.

[0026] The sintering machine 7 is equipped with a sealing cover 703 on its upper part. The sealing cover 703 is installed in the 3 / 10 to 8 / 10 material surface area between the sintering ignition point and the sintering endpoint. The sintering machine 7 is equipped with a heat-resistant combustion fan 701 and a mixing tank 702.

[0027] The oxygen-enriched hot exhaust gas outlet 113 of the flue gas upgrading device 1 is connected to the air inlet of the heat-resistant combustion fan 701 of the sintering machine 7 through the oxygen-enriched exhaust gas pipe 3; the oxygen-enriched steam-enriched hot exhaust gas outlet 114 of the flue gas upgrading device 1 is connected to the sealing cover 703 through the oxygen-enriched steam-enriched exhaust gas pipe 4; the inlet of the steam network 5 is connected to another steam outlet of the steam package 111 of the flue gas upgrading device 1, and the outlet of the steam network 5 is connected to the mixing tank 702 of the sintering machine 7.

[0028] A method for the complete recovery and utilization of waste heat flue gas from sintering ring cooling includes the following steps: (1) Use the high-temperature waste flue gas from the ring-cooled generator set for power generation; (2) The low-temperature waste flue gas of the ring cooling is used as the cooling medium of the ring cooling medium temperature section, and the generated ring cooling medium temperature waste flue gas is obtained by oxygen-enriched supplementary heat combustion to obtain high-temperature oxygen-enriched waste flue gas. (3) Use hot water to exchange heat with high-temperature oxygen-enriched waste flue gas to obtain steam and medium-temperature oxygen-enriched waste flue gas. (4) Hot water and oxygen-enriched waste gas are obtained by exchanging heat between cold water and medium-temperature oxygen-enriched waste gas. (5) Use steam to increase the steam content of oxygen-rich hot waste gas to obtain oxygen-rich steam-rich hot waste gas. (6) The generated oxygen-enriched hot waste gas is used as combustion air for oxygen-enriched hot air sintering. (7) The generated oxygen-rich and steam-rich hot exhaust gas is sent to the sealing cover of the sintering machine for oxygen-rich and steam-rich sintering. (8) The generated steam is sent to the sintering mixing tank to increase the temperature of the mixture.

[0029] In step (1), the temperature of the annularly cooled high-temperature waste flue gas is not lower than 350°C, preferably 400-550°C, and more preferably 450-500°C. In step (2), the temperature of the annularly cooled low-temperature waste gas is not higher than 100℃, preferably 60-90℃, and more preferably 50-80℃; the temperature of the annularly cooled medium-temperature waste gas is not lower than 100℃, preferably 120-250℃, and more preferably 160-230℃; the temperature of the high-temperature oxygen-enriched waste gas is not lower than 200℃, preferably 230-300℃, and more preferably 230-280℃; the oxygen content of the high-temperature oxygen-enriched waste gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%. In step (3), the temperature of the medium-temperature oxygen-enriched waste gas is not higher than 240℃, preferably 190-240℃, and more preferably 210-225℃; the oxygen content of the medium-temperature oxygen-enriched waste gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%; the steam temperature is not higher than 180℃, preferably 130-180℃, and more preferably 150-165℃. In step (4), the temperature of the oxygen-enriched thermal exhaust gas is not higher than 170℃, preferably 120-170℃, and more preferably 140-155℃; the oxygen content of the oxygen-enriched thermal exhaust gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%. In step (5), the temperature of the oxygen-enriched and steam-enriched waste gas is not higher than 180℃, preferably 130-170℃, and more preferably 140-160℃; the oxygen content of the oxygen-enriched and steam-enriched waste gas is not less than 20%, preferably 20-23%, and more preferably 21-22%; the steam concentration of the oxygen-enriched and steam-enriched waste gas is not less than 2wt%, preferably 3-5wt%, and more preferably 4-4.5wt%. In step (5), the proportion of oxygen-enriched thermal waste gas used for steam boosting treatment is 40-60% of the total amount of oxygen-enriched thermal waste gas, preferably 48-58%, and more preferably 52-55%. Example

[0030] The present invention includes a flue gas upgrading device 1, a waste heat generator set 2, an oxygen-enriched waste gas pipeline 3, an oxygen-enriched steam-enriched waste gas pipeline 4, a steam pipeline network 5, a demineralized water pipeline network 6, a sintering machine 7, and an annular cooler 8.

[0031] In this embodiment, the upper part of the annular cooler 8 is divided into a high-temperature section 801, a medium-temperature section 802 and a low-temperature section 803 in the direction of operation. A high-temperature section fan hood 804, a medium-temperature section fan hood 805 and a low-temperature section fan hood 806 are installed in each section of the annular cooler.

[0032] In this embodiment, the top of the high-temperature section hood 804 is connected to the waste heat generator set 2 via an air supply pipe, and the approximately 480°C high-temperature waste flue gas from the annular cooling high-temperature section 801 is used for waste heat power generation; the top air outlet of the low-temperature section hood 803 is connected to the bottom air inlet of the medium-temperature section 802 via an air supply pipe, and the approximately 83°C low-temperature waste flue gas from the annular cooling low-temperature section 803 is used as the cooling medium for the sinter in the medium-temperature section 802, and finally generates approximately 180°C annular cooling medium-temperature waste flue gas in the medium-temperature section 802; the top air outlet of the medium-temperature section hood 805 is connected to the flue gas inlet 101 of the flue gas upgrading device 1 via an air supply pipe, and the annular cooling medium-temperature waste flue gas is transported into the flue gas upgrading device 1.

[0033] The flue gas inlet 101 of the flue gas upgrading device 1 is installed at the bottom of the device. An electric butterfly valve 102 is installed at the flue gas inlet 101 to adjust the air intake of the flue gas upgrading device. The annularly cooled medium-temperature waste flue gas collected from the medium-temperature section hood 805 enters the interior of the flue gas upgrading device 1 through the flue gas inlet 101. The waste flue gas will pass through the oxygen-enriched heating zone 103, the steam generation zone 104, and the diversion steam boosting zone 105 from bottom to top, and finally generate oxygen-enriched hot waste gas, oxygen-enriched steam-enriched hot waste gas, and steam.

[0034] The oxygen-enriched heating zone 103 is equipped with four symmetrically arranged oxygen-enriched burners 106, each with its own combustible gas pipeline 107 and oxygen pipeline 108. The oxygen-enriched burners 106 supplement heat and oxygen to the annularly cooled medium-temperature waste gas passing through the oxygen-enriched combustion zone 106 through oxygen-enriched combustion, thereby obtaining high-temperature oxygen-enriched waste gas with a temperature of approximately 280℃ and an oxygen content of approximately 24%. Preferably, in this embodiment, the combustible gas used in the oxygen-enriched burners is blast furnace gas. Blast furnace gas has relatively low cost and can generally be produced by steel companies themselves. In other embodiments, coke oven gas, converter gas, etc., can also be used as combustible gases.

[0035] A steam generator 109 and a water preheater 110 are installed from bottom to top in the steam generation zone 104, and a steam drum 111 is installed externally. The high-temperature oxygen-enriched waste gas generated from the oxygen-enriched supplementary heating zone 103 first passes through the steam generator 109 when it enters the steam generation zone 104. Through heat exchange with the hot water in the steam generator 109, steam and medium-temperature oxygen-enriched waste gas are obtained. The generated steam temperature is about 180°C, and the generated medium-temperature oxygen-enriched waste gas temperature is about 210°C with an oxygen content of about 24%. Further, the medium-temperature oxygen-enriched waste gas exchanges heat with the water preheater 110 to obtain hot water and oxygen-enriched hot waste gas with a temperature of about 175°C and an oxygen content of about 24%. Furthermore, the cold water inlet of the water preheater is connected to the demineralized water pipeline network 6. The hot water generated by it first enters the steam package 111, and then is transported by the steam package 111 to the steam inlet of the steam generator 109. Part of the steam generated by the steam generator 109 is transported to the steam injection device 115 of the diversion and steam boosting zone 105 as the steam source for injection steam, and the other part is transported to the mixing tank 702 through the steam pipeline network 5 to increase the temperature of the sintering mixture. In this embodiment, the temperature of the mixture can be effectively increased by about 24°C.

[0036] An electric diversion baffle 112 is installed in the middle of the diversion steam booster zone 105, dividing the zone into two independent chambers. The electric diversion baffle 112 can be swung left and right to adjust the air intake of the two chambers. One chamber does not require further treatment of the oxygen-enriched hot exhaust gas; it is directly discharged from the oxygen-enriched hot exhaust gas outlet 113 and transported to the air inlet of the heat-resistant combustion fan 701 through the oxygen-enriched exhaust gas pipeline 3. Ultimately, it is used as the combustion air for the sintering ignition furnace in oxygen-enriched hot air sintering. The other chamber is equipped with a steam injection device 115 at the top, which injects steam... The blowing device 115 blows steam into the oxygen-enriched hot waste gas to obtain oxygen-enriched steam hot waste gas. The temperature of the oxygen-enriched steam hot waste gas is about 172°C, the steam content is about 4.3 wt%, and the oxygen content is about 21.6%. The oxygen-enriched steam hot waste gas is discharged from the oxygen-enriched steam hot waste gas outlet 114 and transported to the sintering sealing cover 703 through the oxygen-enriched steam hot waste gas pipeline 4. Finally, it is blown onto the sintering material surface for oxygen-enriched steam sintering. Preferably, both the oxygen-enriched hot waste gas outlet 113 and the oxygen-enriched steam hot waste gas outlet 114 are equipped with electric regulating valves 116 to regulate the gas output.

[0037] Preferably, in this embodiment, the sealing cover 703 provided on the upper part of the sintering machine 7 is installed in the 3 / 10 to 8 / 10 material surface area between the sintering ignition point and the sintering endpoint.

[0038] Preferably, in this embodiment, the proportion of oxygen-enriched thermal waste gas used for steam boosting treatment is 52% of the total amount of oxygen-enriched thermal waste gas.

[0039] In this invention, using the above embodiments, the waste heat resources of the annular cooling system are utilized in a tiered manner. High-temperature waste gas from the annular cooling system is used for waste heat power generation. The medium- and low-temperature waste gas from the annular cooling system undergoes a series of upgrading treatments to obtain oxygen-enriched hot waste gas, oxygen-enriched steam-enriched hot waste gas, and steam. The oxygen-enriched hot waste gas is further used as combustion air for oxygen-enriched hot air sintering, and the oxygen-enriched steam-enriched hot waste gas is used for oxygen-enriched steam sintering. The generated steam is used to increase the temperature of the sintering mixture. After adopting this system, the sintering waste heat unit generates approximately 13 MW / h of electricity, reduces energy consumption in the sintering process by approximately 18%, reduces particulate matter emissions by approximately 17%, reduces SO2 emissions by approximately 5%, reduces NOx emissions by approximately 9%, reduces CO emissions by approximately 11%, reduces dioxin emissions by approximately 18%, decreases the sintering return rate by approximately 1.1%, and increases the sintering ore conversion intensity by 2.2%. This effectively improves the combustion efficiency of sintering fuel, reduces energy consumption in the sintering process, saves energy costs, reduces pollutant emissions during the sintering process, and improves the quality of sintered ore.

[0040] The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention without departing from the spirit and scope of the present invention. Any modifications or partial substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A system for the complete recovery and utilization of waste heat and flue gas from sintering ring cooling, characterized in that: It includes a flue gas upgrading device (1), a waste heat generator set (2), an oxygen-enriched waste gas pipeline (3), an oxygen-enriched steam waste gas pipeline (4), a steam pipeline network (5), a demineralized water pipeline network (6), a sintering machine (7), and an annular cooler (8). The upper part of the annular cooler (8) is connected to the flue gas upgrading device (1) and the waste heat generator set (2), respectively. The flue gas upgrading device (1) is connected to the steam pipeline network (5) and the demineralized water pipeline network (6). The flue gas upgrading device (1) is connected to the sintering machine (7) through the oxygen-enriched waste gas pipeline (3), the oxygen-enriched steam waste gas pipeline (4), and the steam pipeline network (5).

2. The system for the complete recovery and utilization of waste heat from sintering ring cooling as described in claim 1, characterized in that: The upper part of the ring cooler (8) is divided into a high temperature section (801), a medium temperature section (802) and a low temperature section (803) in the direction of operation. A high temperature section hood (804), a medium temperature section hood (805) and a low temperature section hood (806) are installed on the upper part of each section of the ring cooler. The top of the high temperature section hood (804) is connected to the waste heat generator set (2) through an air supply pipe. The top air outlet of the low temperature section hood (806) is connected to the bottom air inlet of the medium temperature section (805) through an air supply pipe. The top air outlet of the medium temperature section hood (805) is connected to the flue gas inlet (101) of the flue gas upgrading device (1) through an air supply pipe.

3. The system for the complete recovery and utilization of waste flue gas from sintering ring cooling as described in claim 2, characterized in that: The flue gas inlet (101) of the flue gas upgrading device (1) is installed at the bottom of the device, and an electric butterfly valve (102) is installed at the flue gas inlet (101). The medium-temperature waste flue gas collected from the medium-temperature section hood (805) enters the flue gas upgrading device (1) through the flue gas inlet (101). The waste flue gas will pass through the oxygen-enriched heating zone (103), the steam generation zone (104) and the diversion steam boosting zone (105) from bottom to top, and finally generate oxygen-enriched hot waste gas, oxygen-enriched steam-enriched hot waste gas and steam.

4. The system for the complete recovery and utilization of waste heat from sintering ring cooling as described in claim 3, characterized in that: The oxygen-enriched heating zone (103) is equipped with an oxygen-enriched burner (106). There is more than one oxygen-enriched burner (106), and each oxygen-enriched burner is individually equipped with a combustible gas pipeline (107) and an oxygen pipeline (108).

5. A system for the complete recovery and utilization of waste flue gas from sintering ring cooling as described in claim 3, characterized in that: The steam generating zone (104) is equipped with a steam evaporator (109) and a water preheater (110) from bottom to top, and a steam package (111) is installed outside. The inlet of the water preheater (110) is connected to the demineralized water pipeline (6), and the outlet is connected to the hot water inlet of the steam package (111). The hot water inlet of the steam evaporator (109) is connected to the hot water outlet of the steam package (111), and the steam outlet of the steam generator (109) is connected to the steam inlet of the steam package (111). The steam package (111) is equipped with two steam outlets, one of which is connected to the steam inlet of the steam injection device (115) of the diversion steam booster zone (105), and the other outlet is connected to the steam pipeline (5).

6. The system for the complete recovery and utilization of waste flue gas from sintering ring cooling as described in claim 3, characterized in that: The top of the diversion steam boosting zone (105) is equipped with an electric diversion baffle (112), which divides the diversion steam boosting zone (105) into two independent chambers. The top of one chamber is directly connected to the oxygen-enriched hot exhaust gas outlet (113) of the flue gas upgrading device (1). The other chamber is equipped with a steam injection device (115). The steam inlet of the steam injection device (115) is connected to a steam outlet of the steam package (111) through a steam pipe. The top of this chamber is connected to the oxygen-enriched steam-enriched hot exhaust gas outlet (114) of the flue gas upgrading device (1). The electric diversion baffle (112) adjusts the air intake of the two chambers by swinging left and right.

7. A system for the complete recovery and utilization of waste heat from sintering ring cooling as described in claim 1, characterized in that: The sintering machine (7) is equipped with a sealing cover (703) on the upper part. The sealing cover (703) is installed in the 3 / 10 to 8 / 10 material surface area between the sintering ignition point and the sintering endpoint. The sintering machine (7) is equipped with a heat-resistant combustion fan (701) and a mixing tank (702).

8. A system for the complete recovery and utilization of waste flue gas from sintering ring cooling as described in claim 7, characterized in that: The oxygen-enriched hot exhaust gas outlet (113) of the flue gas upgrading device (1) is connected to the air inlet of the heat-resistant combustion fan (701) of the sintering machine (7) through the oxygen-enriched exhaust gas pipe (3); the oxygen-enriched steam-enriched hot exhaust gas outlet (114) of the flue gas upgrading device (1) is connected to the sealing cover (703) through the oxygen-enriched steam-enriched exhaust gas pipe (4); the inlet of the steam network (5) is connected to another steam outlet of the steam package (111) of the flue gas upgrading device (1), and the outlet of the steam network (5) is connected to the mixing tank (702) of the sintering machine (7).

9. A method for the complete recovery and utilization of waste heat from sintering ring cooling, characterized in that... Includes the following steps: (1) Use the high-temperature waste flue gas from the ring-cooled generator set for power generation; (2) The low-temperature waste flue gas of the ring cooling is used as the cooling medium of the ring cooling medium temperature section, and the generated ring cooling medium temperature waste flue gas is obtained by oxygen-enriched supplementary heat combustion to obtain high-temperature oxygen-enriched waste flue gas. (3) Use hot water to exchange heat with high-temperature oxygen-enriched waste flue gas to obtain steam and medium-temperature oxygen-enriched waste flue gas. (4) Hot water and oxygen-enriched waste gas are obtained by exchanging heat between cold water and medium-temperature oxygen-enriched waste gas. (5) Use steam to increase the steam content of oxygen-rich hot waste gas to obtain oxygen-rich steam-rich hot waste gas. (6) The generated oxygen-enriched hot waste gas is used as combustion air for oxygen-enriched hot air sintering. (7) The generated oxygen-rich and steam-rich hot exhaust gas is sent to the sealing cover of the sintering machine for oxygen-rich and steam-rich sintering. (8) The generated steam is sent to the sintering mixing tank to increase the temperature of the mixture.

10. A method for the complete recovery and utilization of waste flue gas from sintering ring cooling as described in claim 9, characterized in that: In step (1), the temperature of the annularly cooled high-temperature waste flue gas is not lower than 350°C, preferably 400-550°C, and more preferably 450-500°C; In step (2), the temperature of the annularly cooled low-temperature waste gas is not higher than 100℃, preferably 60-90℃, and more preferably 50-80℃; the temperature of the annularly cooled medium-temperature waste gas is not lower than 100℃, preferably 120-250℃, and more preferably 160-230℃; the temperature of the high-temperature oxygen-enriched waste gas is not lower than 200℃, preferably 230-300℃, and more preferably 230-280℃; the oxygen content of the high-temperature oxygen-enriched waste gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%. In step (3), the temperature of the medium-temperature oxygen-enriched waste gas is not higher than 240℃, preferably 190-240℃, and more preferably 210-225℃; the oxygen content of the medium-temperature oxygen-enriched waste gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%; the steam temperature is not higher than 180℃, preferably 130-180℃, and more preferably 150-165℃. In step (4), the temperature of the oxygen-enriched thermal exhaust gas is not higher than 170℃, preferably 120-170℃, and more preferably 140-155℃; the oxygen content of the oxygen-enriched thermal exhaust gas is not lower than 23.5%, preferably 23.5-25%, and more preferably 23.5-24%. In step (5), the temperature of the oxygen-enriched and steam-enriched waste gas is not higher than 180℃, preferably 130-170℃, and more preferably 140-160℃; the oxygen content of the oxygen-enriched and steam-enriched waste gas is not less than 20%, preferably 20-23%, and more preferably 21-22%; the steam concentration of the oxygen-enriched and steam-enriched waste gas is not less than 2wt%, preferably 3-5wt%, and more preferably 4-4.5wt%. In step (5), the proportion of oxygen-enriched thermal waste gas used for steam boosting treatment is 40-60% of the total amount of oxygen-enriched thermal waste gas, preferably 48-58%, and more preferably 52-55%.

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