Cooling water supply system of blast furnace air supply device and cooling method

Abstract

The invention belongs to the technical field of blast furnace cooling, and particularly relates to a cooling water supply system of a blast furnace air supply device and a cooling method. One end of a hot water recovery pool is connected with a filter pump through a pipeline, the filter pump is connected with a fiber ball filter, and the fiber ball filter is connected with the hot water recovery pool through a pipeline; the other end of the hot water recycling pool is connected with a lifting pump through a pipeline, the lifting pump is connected with a cooling tower through a pipeline, the cooling tower is connected with a cooling water pool, and one end of the cooling water pool is connected with a high-pressure water pump. The pipeline filters are connected with a tuyere small sleeve of an air supply device, the tuyere small sleeve of the air supply device is connected with a hot water recovery pool through a pipeline, and an accident emergency water supply mechanism is additionally arranged at the water inlet end of the tuyere small sleeve of the air supply device. According to the system, cooling water is provided by the accident emergency water supply mechanism during double-path high-voltage power loss and diesel engine pump idling time, and the tuyere small sleeve is prevented from being burnt out and exploded through continuous water supply.

Description

Technical Field

[0001] The invention belongs to the technical field of blast furnace cooling, and particularly relates to a cooling water supply system and a cooling method for a blast furnace air supply device. Background Art

[0002] The main function of the blast furnace cooling water supply system is to provide cooling water for various equipment to ensure that the heat flux intensity of the equipment is controlled within the tolerable range. The blast furnace cooling water supply system mainly cools the blast furnace body cooling water system, the furnace bottom cooling water system, the air supply device, the cross temperature measuring device, the hydraulic equipment, the mud gun, and the gearbox. Among them, the cooling of the air supply device is the most critical. Generally, a blast furnace has at least 26 sets or more of air supply devices. The heat generated during the air blowing and combustion assistance process needs to be carried away by the cooling water system. The water supply for the air supply device must be continuous without interruption. The temperature of the tuyere small sleeve is high, and the requirements for the cooling water are also high. If the flow rate of the cooling water is not fast enough, the cooling is slow, there is a water cut phenomenon in the cooling water, or in the case of a power system failure and the power-off of the electric pump and the disconnection of the water supply, the tuyere small sleeve is prone to burn-out and explosion accidents. Summary of the Invention

[0003] The purpose of the invention is to provide a cooling water supply system and a cooling method for a blast furnace air supply device to solve the problems that the flow rate of the cooling water in the traditional cooling water supply system is not fast enough, the cooling is slow, there is a water cut phenomenon in the cooling water, or in the case of a power system failure and the power-off of the electric pump and the disconnection of the water supply, the tuyere small sleeve is prone to burn-out and explosion.

[0004] To achieve the above purpose, the invention adopts the following technical solutions: A cooling water supply system for a blast furnace air supply device includes a hot water recovery pool, a cooling water pool, and an accident emergency water supply mechanism. One end of the hot water recovery pool is connected to a filtration pump through a pipeline. The filtration pump is connected to a fiber ball filter through a pipeline. The fiber ball filter is connected to the hot water recovery pool through a pipeline. The other end of the hot water recovery pool is connected to a lifting pump through a pipeline. There are 3 lifting pumps, with two in use and one in reserve. The lifting pump is connected to a cooling tower through a pipeline. The cooling tower is connected to the cooling water pool. One end of the cooling water pool is connected to a high-pressure water pump through a pipeline. There are 4 high-pressure water pumps, with two in use and two in reserve, and they are powered by two high-voltage circuits. A diesel engine pump is connected in parallel at the water inlet end of the high-pressure water pump. The output ends of the high-pressure water pump and the diesel engine pump are both connected to a pipeline filter. The pipeline filters are all connected to the tuyere small sleeve of the air supply device. The tuyere small sleeve of the air supply device is connected to the hot water recovery pool through a pipeline. An accident emergency water supply mechanism is added at the water inlet end of the tuyere small sleeve of the air supply device.

[0005] Preferably, the accident emergency water supply mechanism includes an accident water tower, a make-up water pump, and a liquid level transmitter. A liquid level transmitter is installed inside the accident water tower. The bottom end of the accident water tower is sequentially connected to a first cut-off valve, a first check valve, and a second cut-off valve through a pipeline. The end of the second cut-off valve is branched into two paths through a pipeline and is respectively connected to a third cut-off valve and a fourth cut-off valve. The end of the third cut-off valve is connected to the tuyere sleeve of the air supply device through a pipeline. The end of the fourth cut-off valve is branched into two paths through a pipeline and is respectively connected to a fifth cut-off valve and a sixth cut-off valve. The fifth cut-off valve is connected to the cooling water pool, and the sixth cut-off valve is connected to the sewage pool. One side of the top end of the accident water tower is connected to the front end of the fifth cut-off valve through an overflow pipe, and the other side is connected to the cooling water pool through a make-up water pump. The electric valve of the make-up water pump is interlocked with the liquid level of the cooling water pool and automatically operates according to the liquid level height. The quality of the make-up water is demineralized water.

[0006] Preferably, the output ends of the high-pressure water pump and the diesel engine pump are both connected to the third cut-off valve through a second check valve.

[0007] Preferably, the output ends and input ends of the filtration pump, the lifting pump, the high-pressure water pump, and the pipeline filter are all connected to valves.

[0008] Preferably, the cooling water pool is connected to a water quality adjustment mechanism through a pipeline. The water quality adjustment mechanism includes a chemical dosing metering pump. The cooling water pool is respectively connected to the chemical dosing metering pump and the biocide metering pump through a pipeline. The hot water recovery pool is connected to the pH agent metering pump through a pipeline. The chemical dosing metering pump, the biocide metering pump, and the pH agent metering pump are all one-use-one-spare. The chemical dosing metering pump is connected to a purification tank, and the purification tank contains an alkaline water treatment formula composed of phosphonate (PBTC), sulfonated copolymer (AMPS / AA, etc.), polyaspartic acid, copper corrosion inhibitor, and zinc salt. The biocide metering pump is connected to a microbial control box, and the microbial control box contains oxidizing and non-oxidizing agents. The pH agent metering pump is connected to a soda ash tank, and the soda ash tank contains soda ash.

[0009] Preferably, the hot water recovery pool is of an open type.

[0010] Preferably, the filtration pump is one-use-one-spare.

[0011] Preferably, there are 4 cooling towers, which are environmentally friendly and energy-saving countercurrent cooling towers. The inlet water temperature of the cooling tower is ≤45°C, and the outlet water temperature is ≤28°C. The lifting pump is adjusted and controlled through a variable frequency energy-saving device, and the frequency of the variable frequency is interlocked with the liquid level of the cooling water pool to ensure the high liquid level operation of the cooling water pool.

[0012] Preferably, the fiber ball filter is also connected to a backwashing pump. The backwashing pump is one-use-one-spare. The backwashing water source is filtered water. The fiber ball filter is backwashed once a day, and the backwashing method is automatically controlled by a PLC module.

[0013] A cooling method for a blast furnace air supply device, the specific steps are as follows: S1: The water in the hot water recovery pool enters the fiber ball filter through a filter pump for filtration to remove impurities. The filtered water enters the hot water recovery pool for recycling treatment. The fiber ball filter is backwashed once a day. The backwashing water source uses the filtered water, and the backwashing method is automatically controlled by a PLC module. The backwashed water is discharged for ironmaking slag flushing. S2: The water in the hot water recovery pool is pumped to the cooling tower by 3 lifting pumps in the station for cooling, and the hot water is cooled to below 28°C. The water after cooling in the cooling tower enters the cooling water pool. The operation of the lifting pump is adjusted and controlled by a variable frequency energy-saving device. The frequency of the variable frequency is interlocked with the liquid level of the cooling water pool to ensure the high liquid level operation of the cooling water pool and ensure the normal production of the blast furnace. S3: The cooling water system water quality is improved by adjusting the water quality mechanism in the cooling water pool. (1) Scale and corrosion inhibition treatment: Select excellent performance phosphonates (PBTC), sulfonated copolymers (AMPS / AA, etc.), polyaspartic acid, copper corrosion inhibitor, zinc salt, etc. to form an alkaline water treatment formula. The treatment formula is placed in a purification box and continuously added to the cooling water pool for 24 hours through a chemical dosing metering pump. There are 2 chemical dosing metering pumps, one in use and one standby, to prevent scaling and corrosion. (2) Bactericidal and algaecidal treatment: Oxidizing and non-oxidizing bactericides are placed in a microbial control box, and the oxidizing and non-oxidizing bactericides are alternately used through a bactericide metering pump. There are 2 bactericide metering pumps, one in use and one standby, which is beneficial to the control of microorganisms. (3) pH adjustment: Soda ash is placed in a soda ash box, and soda ash is added to the hot water recovery pool through a pH agent metering pump to adjust the pH to 7. There are 2 pH agent metering pumps, one in use and one standby. S4: The water in the cooling water pool is supplied to the tuyere sleeve of the blast furnace air supply device for the blast furnace user through a high-pressure water pump and a pipeline filter to cool the tuyere sleeve. High water supply pressure is required. There are four high-pressure water pumps at the cooling position, two in use and two standby. The four pumps are respectively powered by 2 high-voltage circuits. The filtration accuracy requirement of the pipeline filter is ≤0.2mm to prevent blockage of equipment by debris in the water. S5: During the operation of the system, due to the evaporation losses of the cooling tower and the blast furnace tuyere, the backwash drainage losses of the fiber ball filter, and the necessary drainage of the blast furnace, the water system is replenished by an automatic water replenishment method. The replenishment water quality is demineralized water. The electric valve of the make-up water pump is interlocked with the liquid level of the cooling water tank and automatically operates according to the liquid level. When the liquid level is lower than 3.5 meters, the electric valve of the make-up water pump automatically opens for water replenishment. When the liquid level is higher than 4.5 meters, the electric valve of the make-up water pump automatically closes to stop water replenishment. At the same time, ultra-high and low liquid level alarms are set on the computer in the control room to remind the operators to handle the abnormal liquid level of the water tank in a timely manner; the make-up water volume is adjusted according to different production loads. Two liquid level gauges are installed in all water tanks to accurately monitor the liquid levels of the hot water recovery tank and the cooling water tank to prevent water waste caused by excessive water levels and water overflow in the water tank; optimize the backwash process of the multi-media filter, reasonably adjust the backwash time and backwash water volume to avoid waste of backwash water, and the backwash water is sent to the ironmaking slag granulation for use; S6: When the dual power supply of the power system of the high-pressure water pump loses power, the high-pressure water pump stops running, and the diesel engine pump automatically starts to supply water. It takes at least 15 seconds of pressurization time for the diesel engine to reach the rated pressure and rated flow. During the above pressurization time, water is supplied through the emergency water supply mechanism. When the electric pump suddenly stops and the pressure drops sharply, the check valve instantly opens, and the water in the emergency water tower instantly enters the pipeline by gravity to supply water for 15 seconds. When the diesel engine pump pressurizes to the rated pressure and flow, the cooling water is supplied by the diesel engine pump. Through the pressure difference, the check valve automatically closes, and the emergency water tower stops supplying water. The volume of the emergency water tower can ensure at least 15 minutes of water supply; the emergency water tower always maintains a high liquid level, and the water replenishment is supplied by the make-up water pump. The start and stop of the make-up water pump are interlocked with the liquid level transmitter. When the liquid level is low, the make-up water pump automatically starts to replenish water. When it reaches the high liquid level, the make-up water pump automatically stops. The high and low liquid levels are set according to the actual production; S7: Under normal operating conditions, the first cut-off valve, the second cut-off valve, the third cut-off valve, and the fifth cut-off valve are in the normally open state, and the fourth cut-off valve and the sixth cut-off valve are in the closed state; when overhauling the first check valve, close the first cut-off valve and the second cut-off valve; when testing the first check valve during the blast furnace shutdown, close the third cut-off valve and open the fourth cut-off valve, and test the return water to the cooling water tank; when it is necessary to clean the emergency water tower to improve the water quality in the tower, close the third cut-off valve, open the fourth cut-off valve and the sixth cut-off valve, and close the fifth cut-off valve; when the fifth cut-off valve is an overflow valve and is normally open, when the liquid level of the emergency water tower is higher than the overflow pipe, the water automatically flows into the cooling water tank; regularly maintain the emergency water tower, and regularly open the sixth cut-off valve for sewage discharge; regularly open the fourth cut-off valve to observe the liquid level of the emergency water tower. If the liquid level continues to drop, it means the system is normal, otherwise the first check valve needs to be repaired; when the water in the emergency water tower loses pressure, the second check valve automatically opens to prevent the water in the emergency water tower from entering the pipeline near the water pump and affecting the cooling water volume of the tuyere sleeve; S8: After the cooling water in the high-pressure cycle cools the tuyere sleeve of the air supply device, it is naturally discharged into the hot water recovery pool through a pipeline. The hot water can be cooled in the hot water recovery pool, and at the same time, the impurities in the water are precipitated to the bottom of the pool.

[0014] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: (1) The high-pressure water pump is used to achieve rapid water supply, and two high-voltage circuits are used for power supply. In the case of one high-voltage power failure, the other high-voltage circuit supplies power to prevent water cut-off. When both high-voltage power supplies are lost and the high-pressure water pump stops running, the parallel diesel engine pump automatically starts to supply water. However, during the idle time from the start of the diesel engine pump to reaching the rated pressure and rated flow rate, the accident emergency water supply mechanism provides cooling water to achieve high-pressure and continuous water supply, avoiding the phenomenon of cooling water cut-off or the burnout and explosion of the tuyere sleeve caused by the disconnection of water supply under the failure of the power system. (2) The function of the check valve is to prevent the process cooling water from entering the accident water tower to relieve pressure during normal operation. When the accident water tower loses pressure, the second check valve automatically opens to prevent the water in the accident water tower from entering the pipeline near the water pump and affecting the cooling water volume of the tuyere sleeve. Multiple pipelines and several cut-off valves are provided between the accident water tower and the cooling water tank. By adjusting the opening and closing of the cut-off valves, the liquid level control, water quality improvement, sewage discharge and maintenance of the accident water tower can be realized. (3) The hot water recovery pool removes impurities through a fiber ball filter to improve water quality. The high-pressure water pump is connected to a pipeline filter to further remove impurities from the water quality and prevent debris in the water from blocking the equipment. (4) The water in the hot water recovery pool is cooled by a lift pump and a cooling tower to meet the cooling water temperature requirements of blast furnace production, effectively utilize the circulating water in the hot water recovery pool, and reduce resource waste. (5) The water quality of the cooling water system is improved by adjusting the water quality mechanism. The phosphonate PBTC and sulfonated copolymer in the purification tank can act as zinc stabilizers in a relatively wide pH range to prevent zinc salts from precipitating on the metal surface in the form of zinc hydroxide to form zinc scale. At the same time, phosphonate PBTC, polyaspartic acid and sulfonated copolymer also have corrosion inhibition and scale and dispersion inhibition properties. While preventing the precipitation of CaCO3 scale and Ca3(PO4)2 scale, they also have good dispersion properties for iron oxides and can operate under relatively wide PH conditions. They can also form a thin and dense anti-corrosion film on the metal surface, effectively inhibiting metal corrosion. The microorganisms are controlled by alternately using oxidizing and non-oxidizing bactericides in the microorganism control box to avoid the formation of biofilms by microorganisms in the stagnant areas on the walls of the cooling equipment and the surface of the blast furnace peephole detection mirrors, causing thermal resistance and improving the cooling efficiency. Since the system uses demineralized water for makeup water, due to the low pH of the demineralized water, the pH of the circulating water is often lower than the normal control requirements, and soda ash is added to the hot water recovery pool to adjust the pH to 7. Description of the Drawings

[0015] Figure 1Schematic structural diagram of an embodiment of the present invention; Figure 2 Schematic structural diagram of the accident emergency water supply mechanism in an embodiment of the present invention.

[0016] Description of reference numerals: 1, hot water recovery tank; 2, cooling water tank; 3, accident emergency water supply mechanism; 301, accident water tower; 302, make-up water pump; 303, liquid level transmitter; 304, first cut-off valve; 305, first check valve; 306, second cut-off valve; 307, third cut-off valve; 308, fourth cut-off valve; 309, fifth cut-off valve; 310, sixth cut-off valve; 311, overflow pipe; 312, second check valve; 4, filtration pump; 5, fiber ball filter; 6, lift pump; 7, cooling tower; 8, high-pressure water pump; 9, pipeline filter; 10, diesel engine pump; 11, tuyere sleeve; 12, sewage tank; 13, chemical dosing metering pump; 14, bactericide metering pump; 15, pH agent metering pump; 16, purification tank; 17, microbial control box; 18, soda ash tank. Detailed implementation manners

[0017] The technical solution of the present invention will be further described below with reference to the drawings and embodiments.

[0018] As Figure 1As shown in the figure, a cooling water supply system for a blast furnace blowing device includes a hot water recovery tank 1, a cooling water tank 2, and an emergency water supply mechanism 3. One end of the hot water recovery tank 1 is connected to a filtration pump 4 through a pipeline. The filtration pump 4 is configured with one in use and one standby. The filtration pump 4 is connected to a fiber ball filter 5 through a pipeline. The fiber ball filter 5 is connected to the hot water recovery tank 1 through a pipeline. The fiber ball filter 5 is also connected to a backwashing pump, and the backwashing pump is configured with one in use and one standby. The backwashing water source uses filtered water. The fiber ball filter 5 is backwashed once a day, and the backwashing method is automatically controlled by a PLC module. The hot water recovery tank 1 is an open type. The other end of the hot water recovery tank 1 is connected to a lifting pump 6 through a pipeline. There are 3 lifting pumps 6, configured with two in use and one standby. The lifting pump 6 is connected to a cooling tower 7 through a pipeline. The cooling tower 7 is connected to the cooling water tank 2. There are 4 cooling towers 7, which are environmentally friendly and energy-saving countercurrent cooling towers. The inlet water temperature of the cooling tower 7 is ≤45°C, and the outlet water temperature is ≤28°C. The lifting pump 6 is adjusted and controlled by a variable frequency energy-saving device, and the frequency of the variable frequency is interlocked with the liquid level of the cooling water tank 2. One end of the cooling water tank 2 is connected to a high-pressure water pump 8 through a pipeline. There are 4 high-pressure water pumps 8, configured with two in use and two standby, and are powered by two high-voltage circuits. A diesel engine pump 10 is connected in parallel at the inlet end of the high-pressure water pump 8. The output ends of the high-pressure water pump 8 and the diesel engine pump 10 are both connected to a pipeline filter 9. The pipeline filter 9 is connected to the tuyere sleeve 11 of the blowing device. The tuyere sleeve 11 of the blowing device is connected to the hot water recovery tank 1 through a pipeline. An emergency water supply mechanism 3 is added at the inlet end of the tuyere sleeve 11 of the blowing device. The cooling water tank 2 is connected to a water quality adjustment mechanism through a pipeline. The water quality adjustment mechanism includes a chemical dosing metering pump 13. The cooling water tank 2 is connected to the chemical dosing metering pump 13 and a bactericide metering pump 14 respectively through pipelines. The hot water recovery tank 1 is connected to a pH agent metering pump 15 through a pipeline. The chemical dosing metering pump 13, the bactericide metering pump 14, and the pH agent metering pump 15 are all configured with one in use and one standby. The chemical dosing metering pump 13 is connected to a purification tank 16. The purification tank 16 contains an alkaline water treatment formula composed of phosphonate (PBTC), sulfonated copolymer (AMPS / AA, etc.), polyaspartic acid, copper corrosion inhibitor, and zinc salt. The bactericide metering pump 14 is connected to a microbial control box 17. The microbial control box 17 contains oxidizing and non-oxidizing agents. The pH agent metering pump 15 is connected to a soda ash tank 18. The soda ash tank 18 contains soda ash; the high-pressure water pump is used to make the water in the cooling water tank enter the pipeline filter to quickly supply water to the tuyere sleeve, fully taking away the heat. The high-pressure water pump is powered by two high-voltage circuits. In the case of a power failure of one high-voltage circuit, the other high-voltage circuit supplies power to prevent water interruption. When both high-voltage circuits lose power and the high-pressure water pump stops running, the diesel engine pump automatically starts to supply water. However, it takes at least 15 seconds of pressurization time for the diesel engine pump to start and reach the rated pressure and rated flow. During the idle time, the emergency water supply mechanism provides cooling water. After reaching the rated pressure and rated flow of the diesel engine pump, the diesel engine pump supplies water to achieve high-pressure and continuous water supply; the water after cooling the tuyere sleeve enters the hot water recovery tank, realizing resource recovery and reuse to avoid waste;The hot water recovery pool is of an open type, which is conducive to the cooling of the recovered water. At the same time, impurities in the water are precipitated to the bottom of the pool through the hot water recovery pool, making the water in the cooling pool clearer; by adjusting the alkaline water treatment formula in the purification tank of the water quality mechanism and combining with the dosing metering pump, zinc salts are prevented from precipitating on the metal surface in the form of zinc hydroxide to form zinc scale, and at the same time, a thin and dense anti-corrosion film is formed on the metal surface, effectively inhibiting metal corrosion; the common bacteria, fungi and algae in the circulating water are inhibited by the oxidizing and non-oxidizing bactericides and the bactericide metering pump in the microbial control box; the pH of the circulating water is adjusted by the soda ash and the pH agent metering pump in the soda ash tank.;

[0019] As Figure 2 shown, the accident emergency water supply mechanism 3 includes an accident water tower 301, a makeup water pump 302 and a liquid level transmitter 303. A liquid level transmitter 303 is arranged inside the accident water tower 301. The bottom end of the accident water tower 301 is sequentially connected to a first cut-off valve 304, a first check valve 305 and a second cut-off valve 306 through a pipeline. The end of the second cut-off valve 306 is divided into two paths through a pipeline and is respectively connected to a third cut-off valve 307 and a fourth cut-off valve 308. The end of the third cut-off valve 307 is connected to the tuyere sleeve 11 of the air supply device through a pipeline. The end of the fourth cut-off valve 308 is divided into two paths through a pipeline and is respectively connected to a fifth cut-off valve 309 and a sixth cut-off valve 310. The fifth cut-off valve 309 is connected to the cooling pool 2, and the sixth cut-off valve 310 is connected to the sewage pool 12. One side of the top end of the accident water tower 301 is connected to the front end of the fifth cut-off valve 309 through an overflow pipe 311, and the other side is connected to the cooling pool 2 through a makeup water pump 302. The electric valve of the makeup water pump 302 is interlocked with the liquid level of the cooling pool 2 and automatically operates according to the liquid level height. The quality of the makeup water is demineralized water. The output ends of the high-pressure water pump 8 and the diesel engine pump 9 are both connected to the third cut-off valve 308 through a second check valve 312. The output ends and input ends of the filter pump 4, the lifting pump 6, the high-pressure water pump 8 and the pipeline filter 9 are all connected to valves; system makeup water is completed through the accident water tower and the makeup water pump, so that the liquid levels in the hot water recovery pool, the cooling pool and the accident water tower meet the requirements; the first check valve prevents process cooling water from entering the accident water tower to relieve pressure during normal operation and automatically opens during pressure loss; the second check valve prevents the water in the accident water tower from entering the pipeline near the water pump to affect the cooling water volume of the furnace tuyere sleeve during system water pressure loss, ensuring safe production.

[0020] The tuyere sleeve water supply standard of this embodiment:

[0021] The tuyere sleeve water quality standard:

[0022] A cooling method for a blast furnace air supply device based on the above cooling water supply system, the specific steps are as follows: S1: The water in the hot water recovery pool 1 enters the fiber ball filter 5 through the filter pump 4 for filtration to remove impurities. The water passing capacity Q of the fiber ball filter 5 is 300 m 3 / h per unit, ensuring that the blast furnace peephole is clean and bright. The filtered water enters the hot water recovery pool 1 for recycling treatment and utilization. The fiber ball filter 5 is backwashed once a day. The backwash pump flow rate Q is 350 m 3 / h, and the head H is 30 m. The backwash water source uses the filtered water, and the backwash method is automatically controlled by the PLC module. The backwashed water is discharged for ironmaking slag washing; S2: The water in the hot water recovery pool 1 is pumped to the cooling tower 7 by 3 lifting pumps 6 in the station for cooling. The model of the lifting pump 6 is XHXS300 - 350, and the flow rate Q is 1500 m 3 / h, and the head H is 21 m. The water passing capacity Q of the cooling tower 7 is 100 m3 / h per unit, and the hot water is cooled to below 28 °C. The water after cooling in the cooling tower 7 enters the cooling water pool 2; the operation of the lifting pump 6 is adjusted and controlled by the variable frequency energy-saving device. The frequency of the variable frequency is interlocked with the liquid level of the cooling water pool 2 to ensure the high liquid level operation of the cooling water pool and the normal production of the blast furnace; S3: The cooling water pool 2 improves the water quality of the cooling water system through the water quality adjustment mechanism. (1) Scale and corrosion inhibition treatment: Select excellent performance phosphonates (PBTC), sulfonated copolymers (AMPS / AA, etc.), polyaspartic acid, copper corrosion inhibitor, zinc salt, etc. to form an alkaline water treatment formula. The treatment formula is placed in the purification box 16 and continuously added to the cooling water pool 2 through the dosing metering pump 13 for 24 hours. There are 2 dosing metering pumps 13 in total, one in use and one standby. The flow rate of the dosing metering pump 13 is 7.6 L / h to prevent scaling and corrosion; (2) Oxidizing and non-oxidizing biocides are placed in the microbial control box 17, and the oxidizing and non-oxidizing biocides are alternately used through the biocide metering pump 14 and continuously added to the cooling water pool 2 through the biocide metering pump 14 for 24 hours. There are 2 biocide metering pumps 14 in total, one in use and one standby. The flow rate of the biocide metering pump 14 is 7.6 L / h. The JG - 992 oxidizing biocide is used, which can penetrate the slime biofilm attached to the wall and play a biocidal and stripping effect; the JG - 990 non-oxidizing biocide sterilizes by breaking the bonds of bacteria and algae proteins and has a strong inhibitory and killing effect on common bacteria, fungi, and algae in the circulating water, ensuring that the residual chlorine is controlled at 0.2 - 0.5 mg / L within 1 - 2 hours after the dosing is completed, which is beneficial to the control of microorganisms. The dosing situation is shown in Table 1; (3) pH adjustment: Soda ash is placed in the soda ash box 18, and soda ash is added to the hot water recovery pool 1 through the pH agent metering pump 15 to adjust the pH to 7. There are 2 pH agent metering pumps 15 in total, one in use and one standby. The flow rate of the pH agent metering pump 15 is 7.6 L / h; Table 1 Scaling and corrosion inhibition and algae killing dosing situation

[0023] S4: The water in the cooling water tank 2 is supplied to the tuyere sleeve 11 of the blast furnace user's air supply device through the high-pressure water pump 8 via the pipeline filter 9 to cool the tuyere sleeve 11. A high water supply pressure is required. Four high-pressure water pumps 8 are set at the cooling position. The model of the high-pressure water pump 8 is OMEGA250-800A, with a flow rate Q = 1003m 3 / h and a head H = 180m. Two are in use and two are in standby. The four pumps are respectively powered by 2 high-voltage circuits. The pipeline filter 9 requires a filtration accuracy of ≤0.2mm to prevent blockage of equipment by debris in the water; S5: During the operation of the system, due to the evaporation losses of the cooling tower 7 and the blast furnace tuyere, the backwashing drainage losses of the fiber ball filter 5, and the necessary drainage of the blast furnace, the water system is replenished by an automatic water replenishment method. The replenishment water quality is desalted water, and the replenishment water quality indicators are shown in Table 2. The electric valve of the makeup water pump 302 is interlocked with the liquid level of the cooling water tank 2 and automatically operates according to the liquid level height. When the liquid level is lower than 3.5 meters, the electric valve of the makeup water pump automatically opens for water replenishment. When the liquid level is higher than 4.5 meters, the electric valve of the makeup water pump automatically closes to stop water replenishment. At the same time, ultra-high and ultra-low liquid level alarms are set on the computer in the operation room to remind the operating personnel to handle the abnormal liquid level of the water tank in a timely manner; The makeup water volume is adjusted according to different production loads. Two liquid level gauges are set for all water tanks to accurately monitor the liquid levels of the hot water recovery tank and the cooling water tank, preventing water waste caused by excessive water levels and water overflow in the water tank; Optimize the backwashing process of the multi-media filter, reasonably adjust the backwashing time and backwashing water volume, avoid waste of backwashing water, and send the backwashing water to the ironmaking slag granulation for use; Table 2 Makeup Water Quality Indicators

[0024] S6: When the dual power supplies of the power system of the high-pressure water pump 8 lose power, the high-pressure water pump 8 stops operating, and the diesel engine pump 9 automatically starts to supply water. It takes at least 15 seconds of pressurization time for the diesel engine to start and reach the rated pressure and rated flow. During the above pressurization time, water is supplied through the accident emergency water supply mechanism 3. When the electric pump suddenly stops and the pressure drops steeply, the first check valve 305 and the second check valve 312 open instantaneously, and the water in the accident water tower 301 instantaneously enters the pipeline by gravity to supplement the water supply for 15 seconds. When the diesel engine pump 9 pressurizes to the rated pressure and flow, the cooling water is supplied by the diesel engine pump 9. Through the pressure difference, the check valve automatically closes, and the accident water tower 301 stops supplying water. The volume of the accident water tower 301 can ensure at least 15 minutes of water supply. The installation height of the accident water tower 301 is at least greater than the water column height converted from the water supply pressure of the water pump main pipe of the cooling water tank 2. If the water supply pressure of the water pump main pipe of the cooling water tank 2 is 10 kgf, the installation height of the accident water tower 301 is at least 100 meters; if the water supply pressure of the water pump main pipe of the cooling water tank 2 is 8 kgf, the installation height of the accident water tower 30 is at least 80 meters; the accident water tower 301 always maintains a high liquid level, and the makeup water is supplied by the makeup water pump 302. The start and stop of the makeup water pump 302 are interlocked with the liquid level transmitter 303. When the liquid level is low, the makeup water pump 302 automatically starts to replenish water, and when it reaches the high liquid level, the makeup water pump 302 automatically stops. The high and low liquid levels are set according to the actual production situation; S7: Under normal operating conditions, the first cut-off valve 304, the second cut-off valve 306, the third cut-off valve 307, and the fifth cut-off valve 309 are in the normally open state, and the fourth cut-off valve 308 and the sixth cut-off valve 310 are in the closed state; when overhauling the first check valve 305, close the first cut-off valve 304 and the second cut-off valve 306; when testing the first check valve 305 during the blast outage, close the third cut-off valve 307, open the fourth cut-off valve 308, and test the water return to the cooling water tank 2; when it is necessary to clean the accident water tower 301 to improve the water quality in the tower, close the third cut-off valve 307, open the fourth cut-off valve 308 and the sixth cut-off valve 310, and close the fifth cut-off valve 309; when the fifth cut-off valve 309 is an overflow valve and is in the normally open state, when the liquid level of the accident water tower 301 is higher than the overflow pipe 311, the water automatically flows into the cooling water tank 2; regularly maintain the accident water tower 301, and regularly open the sixth cut-off valve 310 for sewage discharge; regularly open the fourth cut-off valve 308 to observe the liquid level of the accident water tower 301. If the liquid level continues to drop, it indicates that the system is normal, otherwise, the first check valve 305 needs to be repaired; when the water in the accident water tower 301 loses pressure, the second check valve 312 automatically opens to prevent the water in the accident water tower 301 from entering the pipeline near the water pump and affecting the cooling water volume of the tuyere sleeve 11; S8: After the cooling water in the high-pressure circulation cools the tuyere sleeve 11 of the air supply device, it is naturally discharged to the hot water recovery pool 1 through the pipeline. The hot water can be cooled in the hot water recovery pool 1, and at the same time, the impurities in the water are precipitated to the bottom of the pool.

Claims

1. A cooling water supply system for a blast furnace air supply device, characterized in that, It includes a hot water recovery pool, a cooling water pool and an emergency water supply mechanism. One end of the hot water recovery pool is connected to a filtration pump through a pipeline. The filtration pump is connected to a fiber ball filter through a pipeline. The fiber ball filter is connected to the hot water recovery pool through a pipeline. The other end of the hot water recovery pool is connected to a lifting pump through a pipeline. There are 3 lifting pumps, with two in use and one in standby. The lifting pump is connected to a cooling tower through a pipeline. The cooling tower is connected to the cooling water pool. One end of the cooling water pool is connected to a high-pressure water pump through a pipeline. There are 4 high-pressure water pumps, with two in use and two in standby, and they are powered by two high-voltage circuits. A diesel engine pump is connected in parallel at the water inlet end of the high-pressure water pump. The output ends of the high-pressure water pump and the diesel engine pump are both connected to a pipeline filter. The pipeline filters are all connected to the tuyere sleeve of the air supply device. The tuyere sleeve of the air supply device is connected to the hot water recovery pool through a pipeline. An emergency water supply mechanism is added at the water inlet end of the tuyere sleeve of the air supply device.

2. The cooling water supply system of a blast furnace air supply device according to claim 1, characterized in that, The emergency water supply mechanism includes an emergency water tower, a makeup water pump and a liquid level transmitter. A liquid level transmitter is installed in the emergency water tower. The bottom end of the emergency water tower is sequentially connected to a first cut-off valve, a first check valve and a second cut-off valve through a pipeline. The end of the second cut-off valve is branched into two paths through a pipeline and is respectively connected to a third cut-off valve and a fourth cut-off valve. The end of the third cut-off valve is connected to the tuyere sleeve of the air supply device through a pipeline. The end of the fourth cut-off valve is branched into two paths through a pipeline and is respectively connected to a fifth cut-off valve and a sixth cut-off valve. The fifth cut-off valve is connected to the cooling water pool. The sixth cut-off valve is connected to the sewage pool. One side of the top end of the emergency water tower is connected to the front end of the fifth cut-off valve through an overflow pipe, and the other side is connected to the cooling water pool through a makeup water pump. The electric valve of the makeup water pump is interlocked with the liquid level of the cooling water pool and automatically operates according to the liquid level height. The makeup water quality is demineralized water.

3. The cooling water supply system of a blast furnace air supply device according to claim 2, characterized in that, The output ends of the high-pressure water pump and the diesel engine pump are both connected to the third cut-off valve through a second check valve.

4. The cooling water supply system of a blast furnace air supply device according to claim 3, characterized in that, Valves are connected to the output ends and input ends of the filtration pump, the lifting pump, the high-pressure water pump and the pipeline filter.

5. The cooling water supply system of a blast furnace air supply device according to claim 4, characterized in that The cooling water pool is connected to a water quality adjustment mechanism through a pipeline. The water quality adjustment mechanism includes a chemical dosing metering pump. The cooling water pool is respectively connected to the chemical dosing metering pump and the biocide metering pump through a pipeline. The hot water recovery pool is connected to a pH agent metering pump through a pipeline. The chemical dosing metering pump, the biocide metering pump and the pH agent metering pump all adopt one in use and one in standby. The chemical dosing metering pump is connected to a purification tank. The purification tank contains an alkaline water treatment formula composed of phosphonate (PBTC), sulfonated copolymer (AMPS / AA, etc.), polyaspartic acid, copper corrosion inhibitor and zinc salt. The biocide metering pump is connected to a microbial control tank. The microbial control tank contains oxidizing and non-oxidizing agents. The pH agent metering pump is connected to a soda ash tank. The soda ash tank contains soda ash.

6. The cooling water supply system of a blast furnace air supply device according to claim 1, characterized in that, The hot water recovery pool is an open type.

7. The cooling water supply system of a blast furnace air supply device according to claim 1, characterized in that, The filtration pump adopts one in use and one in standby.

8. The cooling water supply system of a blast furnace air supply device according to claim 1, characterized in that, There are 4 cooling towers, which are environmentally friendly and energy-saving countercurrent cooling towers. The inlet water temperature of the cooling tower ≤ 45 °C, and the outlet water temperature ≤ 28 °C. The lifting pump is adjusted and controlled through a variable frequency energy-saving device. The frequency of the variable frequency is interlocked with the liquid level of the cooling water pool to ensure high liquid level operation of the cooling water pool.

9. The cooling water supply system of a blast furnace air supply device according to claim 1, characterized in that, The fiber ball filter is also connected to a backwash pump. One backwash pump is in use while the other is in reserve. The backwash water source is the filtered water. The fiber ball filter is backwashed once a day, and the backwash mode is automatically controlled by a PLC module.

10. A cooling method for a blast furnace air supply device based on the cooling system described in claim 5, characterized in that, The specific steps are as follows: S1: The water in the hot water recovery tank enters the fiber ball filter through a filter pump for filtration to remove impurities. The filtered water enters the hot water recovery tank for recycling treatment and utilization. The fiber ball filter is backwashed once a day. The backwash water source is the filtered water. The backwash mode is automatically controlled by a PLC module. The backwashed water is discharged for use in ironmaking slag flushing. S2: The water in the hot water recovery tank is pumped to the cooling tower by 3 lift pumps in the station for cooling, and the hot water is cooled to below 28°C. The water after cooling in the cooling tower enters the cooling water tank. The operation of the lift pumps is adjusted and controlled by a variable frequency energy-saving device. The frequency of the variable frequency is interlocked with the liquid level of the cooling water tank to ensure the high-level operation of the cooling water tank and the normal production of the blast furnace. S3: The cooling water tank improves the water quality of the cooling water system through a water quality adjustment mechanism. (1) Scale and corrosion inhibition treatment: Select excellent-performance phosphonates (PBTC), sulfonated copolymers (AMPS / AA, etc.), polyaspartic acid, copper corrosion inhibitor, zinc salt, etc. to form an alkaline water treatment formula. The treatment formula is placed in a purification tank and continuously added to the cooling water tank for 24 hours through a chemical dosing metering pump. There are 2 chemical dosing metering pumps, one in use and the other in reserve, to prevent scaling and corrosion. (2) Bactericidal and algaecidal treatment: Oxidizing and non-oxidizing bactericides are placed in a microbial control box, and the oxidizing and non-oxidizing bactericides are alternately used through a bactericide metering pump. There are 2 bactericide metering pumps, one in use and the other in reserve, which is beneficial to the control of microorganisms. (3) pH adjustment: Soda ash is placed in a soda ash tank, and soda ash is added to the hot water recovery tank through a pH agent metering pump to adjust the pH to 7. There are 2 pH agent metering pumps, one in use and the other in reserve. S4: The water in the cooling water tank is supplied to the tuyere sleeve of the blast furnace user's air supply device through a high-pressure water pump and a pipeline filter for cooling the tuyere sleeve. High water supply pressure is required. There are four high-pressure water pumps at the cooling position, two in use and two in reserve. The four pumps are respectively powered by 2 high-voltage circuits. The filtration accuracy of the pipeline filter is required to be ≤0.2 mm to prevent equipment blockage by debris in the water. S5: During system operation, due to evaporation losses in the cooling tower and blast furnace tuyeres, backwash drainage losses of the fiber ball filter, and necessary drainage of the blast furnace, the water system is replenished by an automatic water replenishment method. The replenishment water quality is demineralized water. The electric valve of the makeup water pump is interlocked with the liquid level of the cooling water tank and automatically operates according to the liquid level. When the liquid level is lower than 3.5 meters, the electric valve of the makeup water pump automatically opens for water replenishment. When the liquid level is higher than 4.5 meters, the electric valve of the makeup water pump automatically closes to stop water replenishment. At the same time, ultra-high and ultra-low liquid level alarms are set on the computer in the control room to remind the operating personnel to handle the abnormal liquid level of the water tank in a timely manner; the makeup water volume is adjusted according to different production loads. Two liquid level gauges are installed in all water tanks to accurately monitor the liquid levels of the hot water recovery tank and the cooling water tank to prevent water waste caused by excessive water levels and water overflow in the water tank; optimize the backwash process of the multi-media filter, reasonably adjust the backwash time and backwash water volume, avoid waste of backwash water, and send the backwash water to the ironmaking slag flushing for use; S6: When the dual power supply of the high-pressure water pump's power system loses power and the high-pressure water pump stops running, the diesel engine pump automatically starts to supply water. It takes at least 15 seconds of pressurization time for the diesel engine to reach the rated pressure and rated flow. During the above pressurization time, water is supplied through the emergency water supply mechanism. When the electric pump suddenly stops and the pressure drops steeply, the check valve instantly opens, and the water in the emergency water tower instantly enters the pipeline by gravity to supplement water for 15 seconds. When the diesel engine pump pressurizes to the rated pressure and flow, the cooling water is supplied by the diesel engine pump. Through the pressure difference, the check valve automatically closes, and the emergency water tower stops supplying water. The volume of the emergency water tower can ensure at least 15 minutes of water supply; the emergency water tower always maintains a high liquid level, and the makeup water is supplied by the makeup water pump. The start and stop of the makeup water pump are interlocked with the liquid level transmitter. When the liquid level is low, the makeup water pump automatically starts to replenish water. When the high liquid level is reached, the makeup water pump automatically stops. The high and low liquid levels are set according to the actual production; S7: Under normal operating conditions, the first cut-off valve, the second cut-off valve, the third cut-off valve, and the fifth cut-off valve are in the normally open state, and the fourth cut-off valve and the sixth cut-off valve are in the closed state; when overhauling the first check valve, close the first cut-off valve and the second cut-off valve; when testing the first check valve during the blast furnace shutdown period, close the third cut-off valve, open the fourth cut-off valve, and test the water return to the cooling water tank; When it is necessary to clean the emergency water tower to improve the water quality in the tower, close the third cut-off valve, open the fourth cut-off valve and the sixth cut-off valve, and close the fifth cut-off valve; when the fifth cut-off valve is an overflow valve and is normally open, when the liquid level in the emergency water tower is higher than the overflow pipe, the water automatically flows into the cooling water tank; regularly maintain the emergency water tower, regularly open the sixth cut-off valve for sewage discharge; regularly open the fourth cut-off valve to observe the liquid level of the emergency water tower. If the liquid level continues to drop, it indicates that the system is normal, otherwise, the first check valve needs to be repaired; when the water in the emergency water tower loses pressure, the second check valve automatically opens to prevent the water in the emergency water tower from entering the pipeline near the water pump and affecting the cooling water volume of the tuyere sleeve; S8: After the cooling water in the high-pressure circulation cools the tuyere sleeve of the air supply device, it is naturally discharged to the hot water recovery tank through the pipeline. The hot water can be cooled in the hot water recovery tank, and at the same time, the impurities in the water are precipitated to the bottom of the tank.

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