European smelting furnace carbon emission reduction method
By decarbonizing and adjusting the top gas of Ouye furnace, the recycling of gas is achieved, the problem of underutilization of vertical furnace gas is solved, the carbon consumption and fuel ratio of Ouye furnace is reduced, the reduction efficiency is improved, and the carbon emission reduction effect is achieved.
Patent Information
- Application Number
- CN202410049953.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-14
- Publication Date
- 2025-07-22
AI Technical Summary
In the existing Ouye furnace, the high reduction gas output from the vertical furnace is not fully utilized, resulting in waste of carbon resources. At the same time, the gas in the gasifier needs to cool down before entering the vertical furnace, resulting in heat loss and energy waste.
After dust removal of the top gas generated by the Ouye furnace vertical furnace, part of it enters the output pipeline network, part of it enters the CO2 removal system, and the low-temperature top gas enters the gas pipeline of the gasifier after pressurization. A pressure regulating and flow control valve group is set to ensure that the temperature of the restored gas entering the vertical furnace is 850℃, and the decarbonized gas is recycled to improve the reduction efficiency.
The carbon consumption of Ouye furnaces has been reduced, and the fuel ratio ton-iron iron is reduced by 80-100kg/t, which significantly reduces carbon consumption of gasifiers, increases the metallization rate of the vertical furnace, and achieves the carbon emission reduction target.
Smart Images
Figure CN120349820A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method for carbon emission reduction in an Ouye furnace. Background Art
[0002] The Ouye furnace gas system consists of the gas generated by the gasifier, cold gas, excess gas, and the gas from the top of the shaft furnace. Among them, for the gas generated by the gasifier, it is necessary to ensure that the CO2 content in the gas is not higher than 12%, and its temperature is controlled not lower than 1000 °C. However, when the shaft furnace operates normally, it is required that the temperature of the reducing gas entering the shaft furnace does not exceed 850 °C. Otherwise, it is easy to cause the shaft furnace to adhere. Therefore, part of the cold gas needs to be added to the gas generated by the gasifier before it enters the shaft furnace to prevent the too-high reducing gas from entering the shaft furnace. At present, part of the gas generated by the gasifier is washed with water to reduce the temperature and dust, and then added to the gas pipeline of the gas generated by the gasifier to ensure that the temperature of the reducing gas entering the shaft furnace is maintained at about 850 °C. The reducing gas entering the shaft furnace completes the reduction reaction in the shaft furnace, reduces the iron-containing raw material to metallic sponge iron, and then enters the gasifier. Finally, the soft melting of the hot metal is completed to form qualified steelmaking hot metal.
[0003] Part of the gas generated at the top of the gasifier arch, which forms a temperature of nearly 1000 °C, is washed with water to reduce the temperature and then added to the gas pipeline of the generated gas. This process design will inevitably lead to heat loss and is a waste of energy. The gas output from the Ouye furnace shaft furnace is rich in highly reducing gases CO and H2. At present, the temperature is only 50 °C, and the carbon in this part of the gas is not fully utilized. It is also a waste of carbon resources. Summary of the Invention
[0004] The purpose of the present invention is to provide a method for carbon emission reduction in an Ouye furnace, realizing the recycling of the gas output from the Ouye furnace, reducing the carbon consumption of the Ouye furnace, and the fuel ratio per ton of iron can be reduced by 80 - 100 kg / t, with remarkable carbon emission reduction effect.
[0005] A method for carbon emission reduction in an Ouye furnace, 1), After the top gas generated by the Ouye furnace shaft furnace is dust-removed, only a part of it enters the output gas pipeline network system, and most of it enters the CO2 removal system after being cooled and pressurized. The main reducing gases in the gas composition after decarbonization are CO and H2; 2. The low-temperature top gas after removing CO2 is transported to the outlet of the gas pipeline of the gasifier; 3. Before the decarbonized top gas enters the gas pipeline of the gasifier, a pressure-regulating and flow-regulating valve group for the decarbonized gas is set; 4. The decarbonized gas after pressure regulation and flow regulation is connected to the gas pipeline of the gasifier; 5. Set the target temperature value before the gas output from the gasifier enters the shaft furnace; 6. When the temperature of the reducing gas entering the shaft furnace exceeds the target value, the low-temperature decarbonized gas regulating valve is opened wider to increase the addition amount of decarbonized gas. After mixing with the gas generated by the gasifier, it enters the shaft furnace, and ensures that the temperature of the reducing gas entering the shaft furnace is maintained at 850 °C; 7. Since the top gas entering the shaft furnace has removed CO2 and the proportion of CO and H2 exceeds 90%, the temperature is also raised to 850 °C after mixing with the gas generated by the gasifier. This kind of high-altitude gas can efficiently reduce the iron ore raw materials in the shaft furnace and increase the metallization rate of the shaft furnace; 8. Since the decarbonized gas enters the shaft furnace again as the reducing gas, the carbon consumption required for gasification in the gasifier can be reduced, achieving the goal of reducing the fuel ratio of the Ouyeel furnace; in addition, the reducing gas from the blast furnace enters the shaft furnace, greatly increasing the metallization rate of the shaft furnace, thereby reducing the carbon consumption for direct reduction in the gasifier, further reducing the coke consumption of the gasifier in the Ouyeel furnace, reducing the fuel ratio of the Ouyeel furnace, and finally achieving the carbon emission reduction goal; Specifically: The gas generated in the gasifier dome enters the cyclone dust collector through the gas generating pipe. After dust removal, the reducing gas enters the shaft furnace through the reducing gas pipe. After participating in the reduction reaction in the shaft furnace, the top gas is formed and enters the top gas dust collector through the top gas pipe network. After passing through the top gas dust collector, part of it forms the output gas and enters the subsequent process through the cut-off valve. Part of the top gas enters the water washing tower through the cut-off valve for water washing and cooling, and then enters the booster through the gas pressure regulating valve to remove CO2. To control the temperature of the reducing gas entering the shaft furnace at 850 °C, the gas after pressure reduction and decarbonization is mixed into the above-mentioned reducing gas pipeline through the gas regulating valve, and the recycling of the top gas after decarbonization can be realized; among them, the decarbonized gas regulating valve and the booster realize the adjustment of the pressure and flow rate of the decarbonized gas, and adjust the gas injection volume according to the temperature requirement of the reducing gas. The temperature of the reducing gas is stably controlled. To ensure that the dust content of the gas entering the pressure reduction and decarbonization device meets the standard, an additional washing, dust removal and cooling device is added before entering the pressure reduction and decarbonization device. In case of system abnormality, the gas from the gasifier can directly enter the gas pipe network through the excess gas line and the gas scrubber without entering the shaft furnace.
[0006] In the present invention, the gas output from the shaft furnace of the Ouyeel furnace is used as the temperature-regulating gas for the gas generated by the gasifier after removing carbon dioxide, enabling as much gas generated by the gasifier to enter the shaft furnace as possible, which can reduce the heat loss of the gas generated by the gasifier. At the same time, the decarbonized gas from the shaft furnace enters the gas generation system again, is heated to 850 °C and then enters the shaft furnace again to participate in the reduction reaction, realizing the recycling of the gas output from the Ouyeel furnace, reducing the carbon consumption of the Ouyeel furnace, and reducing the fuel ratio by 80 - 100 kg / t per ton of iron, with remarkable carbon emission reduction effect. Description of the Drawings
[0007] Figure 1 It is a schematic connection structure diagram of the present invention. Embodiment
[0008] A method for carbon emission reduction in an Ouye furnace 1) After the top gas generated by the shaft furnace of the Ouye furnace is dedusted, only a part enters the output gas pipe network system, and most of it enters the CO2 removal system after cooling and pressurization. The main reducing gases in the decarbonized gas composition are CO and H2; 2. The low-temperature top gas with CO2 removed is transported to the outlet of the gasification furnace gas pipe; 3. Before the decarbonized top gas enters the gasification furnace gas pipe, a pressure regulating and flow regulating valve group for the decarbonized gas is set; 4. The decarbonized gas after pressure regulation and flow regulation is connected to the gasification furnace gas pipe; 5. Set the target temperature value before the gas output from the gasification furnace enters the shaft furnace; 6. When the temperature of the reducing gas entering the shaft furnace exceeds the target value, the low-temperature decarbonized gas regulating valve is opened wider to increase the added amount of decarbonized gas. It is mixed with the gas generated by the gasification furnace and then enters the shaft furnace, and ensures that the temperature of the reducing gas entering the shaft furnace remains at 850 °C; 7. Since the top gas entering the shaft furnace has removed CO2, the proportion of CO and H2 exceeds 90%. After being mixed with the gas generated by the gasification furnace, the temperature is also raised to 850 °C. This high-quality gas can efficiently reduce iron ore raw materials in the shaft furnace and increase the metallization rate of the shaft furnace; 8. Since the decarbonized gas enters the shaft furnace again as the reducing gas, the carbon consumption required for gas production in the gasification furnace can be reduced, achieving the goal of reducing the fuel ratio of the Ouye furnace; in addition, the reducing gas of the blast furnace enters the shaft furnace, greatly increasing the metallization rate of the shaft furnace, and then reducing the carbon consumption for direct reduction in the gasification furnace, further reducing the coke consumption of the gasification furnace of the Ouye furnace, reducing the fuel ratio of the Ouye furnace, and finally achieving the carbon emission reduction goal; Specifically: such as Figure 1As shown in the figure, the top of the gasifier 1 is the gasifier arch roof 5. The producer gas generated by the gasifier arch roof 5 enters the cyclone dust collector 3 through the producer gas pipe 2. After dust removal, the reduced gas enters the shaft furnace 6 through the reduced gas pipe 4. The reduced gas participates in the reduction reaction in the shaft furnace to form top gas, which enters the top gas dust collector 8 through the top gas pipe network 7. After passing through the top gas dust collector, part of the gas forms the output gas and enters the subsequent process through the cut-off valve 9. Part of the top gas enters the water scrubber 10 through the cut-off valve 9, is cooled by water washing, and then enters the booster 13 through the gas pressure regulating valve 12 for pressurization and CO2 removal. To control the temperature of the reduced gas entering the shaft furnace at 850°C, the pressurized and decarbonized gas is mixed into the reduced gas pipeline 4 through the gas regulating valve 14, thus realizing the recycling of the top gas after decarbonization. Among them, the decarbonized gas regulating valve 14 and the booster 13 adjust the pressure and flow rate of the decarbonized gas, and adjust the mixing gas volume according to the temperature requirement of the reduced gas, so as to realize the stable control of the reduced gas temperature. To ensure that the dust content of the gas entering the pressurized decarbonization device meets the standard, an additional set of washing, dust removal and cooling device 10 is added before entering the pressurized decarbonization device. In the case of system abnormalities, the gasifier gas can directly enter the gas pipe network through the excess gas line and the gas scrubber 15 without entering the shaft furnace.
Claims
1. A method for carbon emission reduction in an Ouye furnace, characterized in that: 1), After the top gas generated by the shaft furnace of the Ouye furnace is dust-removed, only a part enters the output gas pipeline system, and most of it enters the CO2 removal system after cooling and pressurization. The main reducing gases in the decarbonized gas are CO and H2; 2), The low-temperature top gas from which CO2 is removed is transported to the outlet of the gasification furnace gas pipeline; 3), Before the decarbonized top gas enters the gasification furnace gas pipeline, a pressure-regulating and flow-regulating valve group for the decarbonized gas is set; 4), The decarbonized gas after pressure regulation and flow regulation is connected to the gasification furnace gas pipeline; 5), Set the target temperature value before the gas output from the gasification furnace enters the shaft furnace; 6), When the temperature of the reducing gas entering the shaft furnace exceeds the target value, the low-temperature decarbonized gas regulating valve is opened wider to increase the addition amount of the decarbonized gas. It is mixed with the gas generated by the gasification furnace and enters the shaft furnace, and ensures that the temperature of the reducing gas entering the shaft furnace remains at 850 °C; 7), The top gas entering the shaft furnace has removed CO2, and the proportion of CO and H2 exceeds 90%. After being mixed with the gas generated by the gasification furnace, the temperature is also raised to 850 °C. This high-altitude gas can efficiently reduce the iron ore raw materials in the shaft furnace and increase the metallization rate of the shaft furnace; 8), Because the decarbonized gas enters the shaft furnace again as the reducing gas, the carbon consumption required for gasification furnace gas production can be reduced, achieving the goal of reducing the fuel ratio of the Ouye furnace; in addition, the blast furnace reducing gas enters the shaft furnace, greatly increasing the metallization rate of the shaft furnace, thereby reducing the direct reduction carbon consumption of the gasification furnace, further reducing the coke consumption of the gasification furnace of the Ouye furnace, reducing the fuel ratio of the Ouye furnace, and finally achieving the carbon emission reduction goal; Specifically: The gas generated by the gasification furnace arch top enters the cyclone dust collector after passing through the gas pipeline. The reducing gas after dust removal enters the shaft furnace through the reducing gas pipeline. The reducing gas participates in the reduction reaction in the shaft furnace to form the top gas, which enters the top gas dust collector through the top gas pipeline network 7. After passing through the top gas dust collector, part of it forms the output gas and enters the subsequent process through the cut-off valve, and part of the top gas enters the water washing tower through the cut-off valve for water washing and cooling, then enters the booster through the gas pressure regulating valve for pressurization and CO2 removal. To control the temperature of the reducing gas entering the shaft furnace at 850 °C, the pressurized and decarbonized gas is introduced into the above-mentioned reducing gas pipeline through the gas regulating valve, and the recycling of the top gas after decarbonization can be realized; among them, the decarbonized gas regulating valve and the booster realize the pressure and flow regulation of the decarbonized gas, and adjust the gas injection volume according to the temperature requirement of the reducing gas.