Optimized energy-saving system for strip steel laminar cooling

Abstract

The optimized energy-saving system comprises a laminar flow cold water pool and a laminar flow hot water pool, a double suction pump is installed on the lower portion of the side face of the laminar flow hot water pool, an outlet of the double suction pump is connected with a plurality of cooling towers through micro-resistance butterfly check valves, and the cooling towers are communicated with the laminar flow cold water pool. The laminar flow cold water pool is connected with a plurality of first side spray pipe sets, a water collecting pool is arranged below the first side spray pipe sets, a splitter plate is installed in the water collecting pool, a cold clean water return pipe is arranged in the water collecting pool and located between the upper portion of the splitter plate and the laminar flow cold water pool, and the water collecting pool is communicated with the laminar flow hot water pool and located on the lower portion of the splitter plate. Hot dirty water and cold purified water are separated by the splitter plate, the cold purified water directly flows into the laminar flow cold water pool and does not pass through the laminar flow hot water pool and the cooling tower, the treatment capacity of the cooling tower is reduced, the hot dirty water is conveyed to the cooling tower through the double-suction pump, the double-suction pump is installed in a low-position self-irrigation mode, the use amount of the pump is reduced, and electric energy is saved.

Description

Technical Field

[0001] The invention relates to the technical field of steel coil production, in particular to an optimized energy-saving system for laminar cooling of steel strips. Background Art

[0002] The steel billets received from the steel mill are used as raw materials for hot rolling. The billets are sent to the heating furnace and heated to a temperature suitable for rolling, usually above the recrystallization temperature, to improve the plasticity of the steel and reduce the deformation resistance. The heated billets are initially rolled through the roughing mill to form thicker steel strips. The steel strips after roughing are then sent to the finishing mill for further rolling to achieve the required thickness and dimensional accuracy. The strips after finishing are cooled by the laminar cooling system.

[0003] In the relevant technology, the strip will be cooled by laminar cooling from the finish rolling to the coiling room. The laminar cooling water and the side spray water will not stop flowing when there is no strip passing. At this time, the low-temperature and clean water will flow directly back to the hot water pool, mixed with the used hot and dirty water, and then pressurized and filtered by three lifting pumps and lifted to the cooling tower for cooling. This not only greatly increases the amount of water for lifting, filtering and cooling, but also significantly reduces the efficiency of filtering and cooling. Obviously, this is a huge waste of energy. Summary of the invention

[0004] The object of the present invention is to provide an optimized energy-saving system for laminar cooling of steel strips to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions: an optimized energy-saving system for laminar cooling of steel strips, comprising a laminar cold water pool and a laminar hot water pool, a double-suction pump is installed at the lower part of the side of the laminar hot water pool, the outlet of the double-suction pump is connected to a plurality of cooling towers through a micro-resistance butterfly check valve, and the cooling towers are connected to the laminar cold water pool; The laminar cold water pool is connected to a plurality of first side nozzle groups, a water collecting pool is provided below the first side nozzle group, a diverter plate is installed inside the water collecting pool, a cold clean water return pipe is provided in the water collecting pool and between the upper part of the diverter plate and the laminar cold water pool, and the water collecting pool and the lower part of the diverter plate are connected to the laminar hot water pool; When the strip is not cooled, low-temperature clean water flows directly to the laminar cold water pool, avoiding flowing into the laminar hot water pool. The amount of water that needs to be lifted, filtered and cooled is reduced. The water is pressurized by a double-suction pump, which is more energy-efficient and reduces the number of pumps used.

[0006] Furthermore, the laminar hot water pool is connected to a hot dirty return water tank, which is connected to the water collection tank through a hot dirty return water pipe. The water used to flush the strip flows to the hot dirty return water tank and then enters the laminar hot water pool, waiting to be filtered and cooled before being reused.

[0007] Furthermore, a backup pump is installed between the laminar hot water pool and the double-suction pump. The backup pump is installed with a first valve. When the double-suction pump needs to be maintained, the backup pump can send hot dirty water to the cooling tower to replenish clean cold water for the laminar cold water pool.

[0008] Furthermore, the plurality of cooling towers are connected with a main discharge pipe, which is connected with the laminar flow cold water pool through a branch pipe, so that clean low-temperature water can be quickly added to the laminar flow cold water pool to provide water for strip cooling.

[0009] Furthermore, an auxiliary pool is provided on the side of the water collecting pool, the laminar cold water pool is connected to a second side nozzle group, and the second side nozzle group is matched with the auxiliary pool, and the auxiliary pool is connected to the cooling tower through a suction pump and an auxiliary pipe, which can improve the cooling effect of the strip and deliver water to the cooling tower separately, which can shorten the route.

[0010] Compared with the prior art, the present invention has the following beneficial effects: (1) In the water collection tank, hot dirty water and cold clean water are separated by the diverter plate. When there is no strip to be cooled, the cold clean water sprayed by the first side nozzle group flows directly to the laminar cold water tank without passing through the laminar hot water tank and the cooling tower, thereby reducing the processing capacity of the cooling tower and reducing the operation of one lift pump.

[0011] (2) A double-suction pump is used to deliver hot dirty water to the cooling tower. The double-suction pump is selected with core parameters that are closest to the actual working conditions. It is installed in a low-level self-priming manner and is equipped with a micro-resistance butterfly check valve as the only working pump to reduce pump usage and save electricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a flow chart of the present invention.

[0013] In the figure: 1, laminar cold water tank; 2, suction pump; 3, water collecting tank; 4, auxiliary tank; 5, auxiliary pipe; 6, first side nozzle group; 7, cold clean return pipe; 8, hot dirty return pipe; 9, hot dirty return tank; 10, laminar hot water tank; 11, spare pump; 12, spare pipe; 13, double suction pump; 14, main discharge pipe; 15, branch pipe; 16, cooling tower; 17, diverter plate; 18, first valve; 19, second valve; 20, second side nozzle group; 21, micro-resistance butterfly check valve. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] Example: See also Figure 1 The present invention provides a technical solution: an optimized energy-saving system for laminar cooling of steel strip, comprising a laminar cold water pool 1 and a laminar hot water pool 10, a double-suction pump 13 is installed at the lower part of the side of the laminar hot water pool 10, and the outlet of the double-suction pump 13 is connected to a plurality of cooling towers 16 through a micro-resistance butterfly check valve 21, and the cooling towers 16 are connected to the laminar cold water pool 1; A double-suction pump 13 with matching parameters is selected based on actual working conditions. The double-suction pump 13 is located at the lower side of the laminar hot water pool 10 to achieve low-level water filling operation. At the same time, a micro-resistance butterfly check valve 21 is used to minimize energy consumption loss and save more electricity. The laminar cold water pool 1 is connected to a plurality of first side nozzle groups 6, a water collecting pool 3 is provided below the first side nozzle group 6, a diverter plate 17 is installed inside the water collecting pool 3, a cold clean water return pipe 7 is provided in the water collecting pool 3 and located between the upper part of the diverter plate 17 and the laminar cold water pool 1, and the water collecting pool 3 and located below the diverter plate 17 are connected to the laminar hot water pool 10; The diverter plate 17 is controlled by a hoisting device or a telescopic device so that the diverter plate 17 can swing. When the strip steel is cooling, the diverter plate 17 tilts downward, and the first side nozzle group 6 sprays low-temperature clean water (cold clean water) onto the strip steel. The cold clean water cools the strip steel and becomes high-temperature dirty water (hot dirty water). When there is no strip cooling, the diverter plate 17 tilts upward to guide the cold clean water to flow to the cold clean water return pipe 7.

[0016] In this embodiment, if Figure 1 As shown, the laminar flow hot water pool 10 is connected to a hot and dirty water return tank 9, and the hot and dirty water return tank 9 is connected to the water collection tank 3 through a hot and dirty water return pipe 8. The hot and dirty water return tank 9 temporarily stores hot and dirty water and sends the hot and dirty water to the laminar flow hot water pool 10 by overflow. Some impurities can sink to the bottom of the hot and dirty water return tank 9. The hot and dirty water return tank 9 is equipped with a sewage pipe to discharge the sediment.

[0017] In this embodiment, if Figure 1 As shown, a standby pump 11 is installed between the laminar hot water tank 10 and the double-suction pump 13, and the standby pump 11 is installed with a first valve 18. When the standby pump 11 is not in use, the first valve 18 is closed. When the double-suction pump 13 needs to be maintained, the first valve 18 is opened and the standby pump 11 is started without stopping the cooling process of the strip.

[0018] In this embodiment, if Figure 1 As shown, a spare pipe 12 is installed between the laminar hot water pool 10 and the cooling tower 16, and the spare pipe 12 has a second valve 19. The pipe corresponding to the double-suction pump 13 and the pipe corresponding to the spare pump 11 need to be inspected. The spare pipe 12 can be used in an emergency with an additional emergency pump.

[0019] In this embodiment, the plurality of cooling towers 16 are connected to a main discharge pipe 14, and the main discharge pipe 14 is connected to the laminar cold water pool 1 through a branch pipe 15. After the cooling tower 16 lowers the water temperature, the water returns to the laminar cold water pool 1 for reuse, thereby realizing water recycling.

[0020] In this embodiment, an auxiliary pool 4 is provided on the side of the water collecting pool 3, the laminar cold water pool 1 is connected to the second side nozzle group 20, and the second side nozzle group 20 is matched with the auxiliary pool 4, the auxiliary pool 4 is connected with the cooling tower 16 through the suction pump 2 and the auxiliary pipe 5, the strip steel passing through the auxiliary pool 4 has been cooled by the first side nozzle group 6, the temperature is relatively low and there are few impurities, so the water in the auxiliary pool 4 is sent to the cooling tower 16 through the suction pump 2 for cooling and reuse, and the pipeline layout is better.

[0021] Specifically, when in use, when the steel strip passes through the water collecting pool 3, the first side nozzle group 6 extracts cold clean water in the laminar flow cold water pool 1 and sprays it onto the steel strip, and the cold clean water is left on the steel strip and becomes hot dirty water. The diverter plate 17 is tilted downward to ensure that the hot dirty water flows to the bottom of the water collecting pool 3, and the hot dirty water enters the hot dirty return water tank 9 through the hot dirty return water pipe 8. Some impurities are precipitated in the lower part of the hot dirty return water tank 9. After the hot dirty return water tank 9 is filled with water, the hot dirty water flows to the laminar flow hot water pool 10, and the double suction pump 13 extracts the hot dirty water in the laminar flow hot water pool 10 and sends it to the cooling tower 16. Before the hot dirty water enters the cooling tower 16, multiple activated carbon filters, magnetic filter screens, filter screens, etc. are used to remove impurities and the hot dirty water becomes hot clean water. The hot clean water is sent to the cooling tower 16 for cooling, becomes cold clean water, and returns to the laminar flow cold water pool 1 through the main discharge pipe 14 and the branch pipe 15; When there is no strip steel passing through the water collecting pool 3, the diverter plate 17 is tilted upward, and the cold clean water sprayed from the first side nozzle group 6 flows into the cold clean return water pipe 7 along the diverter plate 17 without entering the hot dirty return water tank 9. After reducing the amount of water in the hot dirty return water tank 9, the temperature and turbidity of the hot dirty water in the laminar hot water pool 10 are greatly improved, which will significantly improve the efficiency of filtering and cooling treatment, providing a better solution for strip steel cooling.

[0022] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An optimized energy-saving system for laminar cooling of steel strips, comprising a laminar cold water pool (1) and a laminar hot water pool (10), characterized in that: A double-suction pump (13) is installed at the lower part of the side of the laminar hot water pool (10), and the outlet of the double-suction pump (13) is connected to a plurality of cooling towers (16) via a micro-resistance butterfly check valve (21), and the cooling towers (16) are connected to the laminar cold water pool (1); The laminar cold water pool (1) is connected to a plurality of first side nozzle groups (6), a water collecting pool (3) is provided below the first side nozzle group (6), a diverter plate (17) is installed inside the water collecting pool (3), a cold clean water return pipe (7) is provided in the water collecting pool (3) and located between the upper part of the diverter plate (17) and the laminar cold water pool (1), and the water collecting pool (3) and located below the diverter plate (17) are connected to the laminar hot water pool (10).

2. The optimized energy-saving system for laminar cooling of steel strip according to claim 1, characterized in that: The laminar hot water pool (10) is connected to a hot and dirty water return tank (9), and the hot and dirty water return tank (9) is connected to the water collection tank (3) via a hot and dirty water return pipe (8).

3. The optimized energy-saving system for laminar cooling of steel strip according to claim 1, characterized in that: A backup pump (11) is installed between the laminar hot water tank (10) and the double-suction pump (13), and the backup pump (11) is installed with a first valve (18).

4. The optimized energy-saving system for laminar cooling of steel strip according to claim 1, characterized in that: A spare pipe (12) is installed between the laminar hot water pool (10) and the cooling tower (16), and the spare pipe (12) is provided with a second valve (19).

5. The optimized energy-saving system for laminar cooling of steel strip according to claim 1, characterized in that: The plurality of cooling towers (16) are connected to a main discharge pipe (14), and the main discharge pipe (14) is connected to the laminar flow cold water pool (1) via a branch pipe (15).

6. The optimized energy-saving system for laminar cooling of steel strip according to claim 1, characterized in that: An auxiliary pool (4) is provided on the side of the water collecting pool (3), and the laminar cold water pool (1) is connected to a second side nozzle group (20), and the second side nozzle group (20) matches the auxiliary pool (4).

7. The optimized energy-saving system for laminar cooling of steel strip according to claim 6, characterized in that: The auxiliary pool (4) is connected to the cooling tower (16) via a suction pump (2) and an auxiliary pipe (5).

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