A hot well tank liquid level regulating device and method

Abstract

The present invention provides a hot well tank liquid level regulating device and method. The device includes a control system, a drainage pump system, a hot well tank, a liquid level gauge, a drainage collecting pipe, a collecting pipe bypass pipeline, and a hot well tank bypass return water pipeline. The outlet of the hot well tank is connected to the drainage pump system, and the drainage outlets of the drainage pump system are all communicated with the drainage collecting pipe. A collecting pipe bypass pipeline is provided between one end of the hot well tank bypass return water pipeline and the drainage collecting pipe, and an adjusting device is provided on the collecting pipe bypass pipeline. A liquid level gauge is provided in the hot well tank, and the control system is electrically connected to the liquid level gauge, the adjusting device, and the drainage pump system respectively. This device can avoid the frequent start and stop of the drainage pumps for the turbidity ring cooling water of the vacuum pump system, extend the service life of the pump body and the motor, reduce the failure rate, reduce the impact on the RH power supply network, reduce the maintenance intensity and frequency of the equipment, improve the working efficiency, effectively ensure the smooth progress of production, and reduce the production cost.

Description

Technical Field

[0001] The present invention belongs to the field of liquid level regulation of the dirty circulating water hot well tank in the molten steel vacuum refining system, and particularly relates to a liquid level regulation device and method for a hot well tank. Background Technique

[0002] The dirty circulating water of the molten steel vacuum refining system is discharged into the hot well tank fixed on the floor foundation at the site through the condenser drain pipe. The hot well tank can seal the three drain pipes to ensure the vacuum of the system; there is a hot well return water pumping station arranged on the floor beside the hot well tank, which is used to return the dirty circulating water in the hot well tank to the water treatment system for cooling and treatment for recycling. The monitoring and signaling of the water level in the hot well tank are realized through a liquid level gauge inserted into the hot well tank, and are interlocked with the working system of the return water pump. The return water pump is designed with three units, and a two-use-one-spare working system is adopted. Since the inlet water flow will change during vacuum treatment and non-vacuum treatment, it is impossible to keep the water level unchanged in the hot well tank. Only by adjusting the inlet and outlet water flows to form a dynamic balance can accidents be avoided: when the water level is too high and the tank is full, the water level rises to the accumulated water in the condenser, triggering a system alarm, resulting in a sudden stop of the vacuum treatment and causing an accident; when the water level is too low, the drain port sucks air, causing the water pump to malfunction and stop draining, and finally the water level is too high and the tank is full, resulting in the same accident as described above.

[0003] At present, for the drainage pumps adopting the two-use-one-spare working system, one is continuously running, one is intermittently running, and one is a standby and emergency start-up pump. Among them, the intermittently operating water pump starts and stops according to the change of the liquid level in the hot well tank. Due to the limitation of the RH area space and platform elevation, the volume of the hot well tank cannot be infinitely enlarged. The limited volume makes the intermittently operating drainage pump start and stop once every 15 - 20 minutes. Such a working condition will greatly shorten the service life of the water pump motor, water pump mechanical seal and bearing with a large power, result in frequent failures, and cannot ensure the continuous and smooth progress of production. Moreover, each start and stop will cause a large impact on the power supply network in the refining area and affect other electrical equipment. Summary of the Invention

[0004] In order to overcome the problems that the service life of the water pump motor, water pump mechanical seal and bearing is greatly shortened due to the frequent start and stop of the hot well pump in the existing working mode of the drainage pump, frequent failures, and a large impact on the power supply network in the refining area, the present invention provides a liquid level regulation device and method for a hot well tank. The present invention adjusts the amount and flow rate of the water returned to the hot well tank through the regulating device, so that the liquid level in the hot well tank is always in a dynamic balance, avoiding the defects of greatly shortening the service life of the water pump motor, water pump mechanical seal and bearing due to the frequent start and stop of the hot well pump, frequent failures, and a large impact on the power supply network in the refining area.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A hot well tank liquid level regulating device includes a control system, a drainage pump system, a hot well tank, a liquid level gauge, a drainage manifold, a manifold bypass pipeline, and a hot well tank bypass return water pipeline. The outlet of the hot well tank is connected to the drainage pump system, and the drainage outlets of the drainage pump system are all communicated with the drainage manifold. A manifold bypass pipeline is provided between one end of the hot well tank bypass return water pipeline and the drainage manifold, and an adjusting device is provided on the manifold bypass pipeline. A liquid level gauge is provided in the hot well tank, and the control system is electrically connected to the liquid level gauge, the adjusting device, and the drainage pump system by electrical signals.

[0007] The drainage pump system includes at least three drainage pumps arranged in parallel, namely drainage pump one, drainage pump two, and drainage pump three. Among them, drainage pump one and drainage pump two are intermittent operation water pumps, and drainage pump three is a standby water pump.

[0008] The adjusting device includes a manual control valve one, a cut-off valve, and a manual control valve two. The manual control valve one and the manual control valve two are respectively located at both ends of the cut-off valve.

[0009] The manifold bypass pipeline is an L-shaped pipeline.

[0010] The outlet of the hot well tank bypass return water pipeline is connected to the return port at the top of the hot well tank.

[0011] The cut-off valve is a pneumatic or electric butterfly valve.

[0012] The hot well tank is fixed to the ground by brackets.

[0013] The hot well tank bypass return water pipeline includes a vertical section, a corner section, and a horizontal section. The vertical section is connected to the horizontal section through the corner section. The corner section is an arc, and the horizontal section is lower than the bottom end of the hot well tank.

[0014] A method for regulating the liquid level of a hot well tank, the specific steps are as follows: the cut-off valve in the adjusting device opens when the water level drops to a certain set liquid level before the liquid level at which drainage pump two stops. At this time, part of the turbid circulating water in the drainage manifold will flow back into the hot well tank along the manifold bypass pipeline and the hot well tank bypass return water pipeline, so that the water level in the hot well tank rises. When it rises to a certain set liquid level before the starting liquid level of drainage pump three, the cut-off valve is closed. At this time, the water level in the hot well tank will drop again until the set liquid level at which the cut-off valve opens, and so on to achieve a dynamic balance of the water level in the hot well tank.

[0015] When the cut-off valve cannot be opened due to a fault, the balance of the water level in the hot well tank is achieved by starting and stopping drainage pump two.

[0016] The beneficial effects of the present invention are:

[0017] The present invention adjusts the water volume and flow rate in the return hot well tank through an adjusting device, so that the liquid level in the hot well tank is always in a dynamic balance, eliminating the original intermittent start-stop working mode of the water pump, thereby avoiding the defects of greatly shortening the service life of the water pump motor, water pump mechanical seal and bearing due to frequent start-stop of the hot well pump, frequent failures and causing a large impact on the power supply network in the refining area.

[0018] The following will be further described with reference to the accompanying drawings. Brief Description of the Drawings

[0019] Figure 1 It is a schematic top view structure diagram of the present invention.

[0020] Figure 2 It is a schematic front view structure diagram of the present invention.

[0021] In the figure: 1, hot well tank; 2, liquid level gauge; 3, drainage pump system; 301, drainage pump one; 302, drainage pump two; 303, drainage pump three; 4, drainage collecting pipe; 5, collecting pipe bypass pipeline; 6, manual regulating valve; 7, pneumatic (electric) butterfly valve; 8, manual regulating valve; 9, hot well tank bypass return water pipeline. Detailed Embodiments

[0022] Embodiment 1:

[0023] In order to overcome the problems of greatly shortening the service life of the water pump motor, water pump mechanical seal and bearing due to frequent start-stop of the hot well pump in the existing drainage pump working mode, frequent failures and causing a large impact on the power supply network in the refining area, the present invention provides a hot well tank liquid level adjusting device and method as shown in Figure 1 and Figure 2 The present invention adjusts the water volume and flow rate in the return hot well tank through an adjusting device, so that the liquid level in the hot well tank is always in a dynamic balance, avoiding the defects of greatly shortening the service life of the water pump motor, water pump mechanical seal and bearing due to frequent start-stop of the hot well pump, frequent failures and causing a large impact on the power supply network in the refining area.

[0024] A hot well tank liquid level adjusting device, characterized in that: it includes a control system, a drainage pump system 3, a hot well tank 1, a liquid level gauge 2, a drainage collecting pipe 4, a collecting pipe bypass pipeline 5 and a hot well tank bypass return water pipeline 9. The outlet of the hot well tank 1 is connected to the drainage pump system 3, and the drainage outlets of the drainage pump system 3 are all communicated with the drainage collecting pipe 4; there is a collecting pipe bypass pipeline 5 between one end of the hot well tank bypass return water pipeline 9 and the drainage collecting pipe 4, and an adjusting device is provided on the collecting pipe bypass pipeline 5; a liquid level gauge is provided in the hot well tank 1, and the control system is electrically connected to the liquid level gauge, the adjusting device and the drainage pump system 3 respectively.

[0025] As shown in Figure 1 andFigure 2 As shown, the bypass pipe 5 of the collecting pipe is connected in series to the return water pipe 9 of the hot well tank bypass between the drainage collecting pipe 4 and the hot well tank 1. The regulating device is used to regulate the water volume and flow rate returning to the hot well tank, so that the liquid level in the hot well tank is always in a dynamic balance, eliminating the original intermittent start-stop working mode of the water pump, thus avoiding the defects of greatly shortened service life of the water pump motor, water pump mechanical seal and bearing caused by frequent start-stop of the hot well pump, frequent failures and a large impact on the power supply network in the refining area.

[0026] In this device, the water in the drainage collecting pipe 4 is discharged for subsequent water treatment. This device can avoid the frequent start and stop of the drainage pump for the turbocirculating cooling water of the vacuum pump system, extend the service life of the water pump body and the motor, reduce the failure rate, reduce the impact on the RH power supply network, reduce the maintenance intensity and frequency of the equipment, improve the work efficiency, effectively ensure the smooth progress of production, and reduce the production cost.

[0027] Embodiment 2:

[0028] Based on Embodiment 1, in this embodiment, preferably, the drainage pump system 3 includes at least three drainage pumps arranged in parallel, namely drainage pump one 301, drainage pump two 302 and drainage pump three 303. Among them, drainage pump one 301 and drainage pump two 302 are intermittent operation water pumps, and drainage pump three 303 is a standby water pump.

[0029] Preferably, the regulating device includes manual regulating valve one 6, cut-off valve 7 and manual regulating valve two 8. Manual regulating valve one 6 and manual regulating valve two 8 are respectively located at both ends of the cut-off valve 7.

[0030] Preferably, the bypass pipe 5 of the collecting pipe is an L-shaped pipe.

[0031] Preferably, the outlet of the return water pipe 9 of the hot well tank bypass is connected to the return port at the top of the hot well tank 1.

[0032] Preferably, the cut-off valve 7 is a pneumatic or electric butterfly valve.

[0033] Preferably, the hot well tank 1 is fixed to the ground by a bracket.

[0034] Preferably, the return water pipe 9 of the hot well tank bypass includes a vertical section, a corner section and a horizontal section. The vertical section is connected to the horizontal section through the corner section. The corner section is an arc, and the horizontal section is lower than the bottom end of the hot well tank 1.

[0035] The present invention provides a method for regulating the liquid level of a hot well tank. The specific steps are as follows: The cut-off valve 7 in the regulating device opens when the water level drops to a certain set liquid level before the stop liquid level of the second drainage pump 302. At this time, part of the turbid circulating water in the drainage collecting pipe 4 will flow back into the hot well tank 1 along the collecting pipe bypass pipeline 5 and the hot well tank bypass return water pipeline 9, so that the water level in the hot well tank 1 rises. When it rises to a certain set liquid level before the start liquid level of the third drainage pump 303, the cut-off valve 7 is closed. At this time, the water level in the hot well tank 1 will drop again until the set liquid level at which the cut-off valve 7 opens. This process repeats to keep the water level in the hot well tank 1 in dynamic balance.

[0036] When the cut-off valve 7 cannot open due to a fault, the balance of the water level in the hot well tank is achieved by starting and stopping the second drainage pump 302.

[0037] In the present invention, the collecting pipe bypass pipeline 5 is serially installed on the hot well tank bypass return water pipeline 9 between the drainage collecting pipe 4 and the hot well tank 1. The regulating device is installed on the collecting pipe bypass pipeline 5. The manual regulating valve 6, the cut-off valve 7, and the manual regulating valve 8 in the regulating device are used to regulate the amount and flow rate of the water returning to the hot well tank, so that the liquid level in the hot well tank is always in a dynamic balance, eliminating the original intermittent start-stop working mode of the water pump, thereby avoiding the defects of greatly shortened service life of the water pump motor, the water pump mechanical seal, and the bearing due to frequent start-stop of the hot well pump, frequent failures, and a large impact on the power supply network in the refining area.

[0038] Five liquid level values are set in the hot well tank 1 from bottom to top. The liquid level value of liquid level one to the liquid level value of liquid level five increases in sequence. The liquid level value of liquid level five is the opening value of the third drainage pump 303, the liquid level value of liquid level four is the start value of the second drainage pump 302, the liquid level value of liquid level three is the stop value of the second drainage pump 302, the liquid level value of liquid level two is the start value of the first drainage pump 301, and the liquid level value of liquid level one is the stop value of the first drainage pump 301.

[0039] Among them, liquid level five and liquid level four are located in the upper part of the hot well tank 1, and liquid level three, liquid level two, and liquid level one are located in the lower part of the hot well tank 1. When the liquid in the hot well tank 1 does not exceed liquid level one, none of the three drainage pumps are opened; when the liquid in the hot well tank 1 exceeds liquid level two, the first drainage pump is opened. In the working mode, while keeping the original start-stop water levels of the water pumps unchanged, such as Figure 2As shown, the cut-off valve 7 in the regulating device opens when the water level drops to a certain set level before the stop level of the second drainage pump 302 (intermittent operation pump). At this time, some turbid circulating water in the 4 drainage header will flow back to the hot well tank 1 along the header bypass pipe 5 and the hot well tank bypass return pipe 9. In this way, the water level in the hot well tank 1 gradually rises. When it rises to a certain set level before the start level of the third drainage pump 303 (standby pump), it closes. At this time, the water level in the hot well tank 1 will slowly drop again until it reaches the set level at which the cut-off valve 7 opens. This process repeats to achieve a dynamic balance of the water level in the hot well tank 1, without the need for the short-term start and stop of the original second drainage pump 302 (intermittent operation pump), thus solving the technical problems in the original working mode. When the total water inflow is less than a certain value, the cut-off valve 7 will not act.

[0040] Even when the cut-off valve 7 cannot open due to a fault, by closing the manual regulating valve 1 6 and the manual regulating valve 2 8 to close the bypass pipe, in the original working mode of the pump, the balance of the water level in the hot well tank can still be achieved through the start and stop of the second drainage pump 302 (intermittent operation pump), ensuring the continuous normal production of the steel plant.

[0041] The above examples are only illustrative of the present invention and do not constitute a limitation on the protection scope of the present invention. Any design identical or similar to the present invention falls within the protection scope of the present invention. The device structure and method steps not described in detail in the present invention are prior arts and will not be further described in the present invention.

Claims

1. A hot well tank liquid level regulating device, characterized in that: It includes a control system, a drainage pump system (3), a hot well tank (1), a liquid level gauge (2), a drainage manifold (4), a manifold bypass pipeline (5), and a hot well tank bypass return pipeline (9). The outlet of the hot well tank (1) is connected to the drainage pump system (3), and the drainage outlets of the drainage pump system (3) are all communicated with the drainage manifold (4); there is a manifold bypass pipeline (5) between one end of the hot well tank bypass return pipeline (9) and the drainage manifold (4), and an adjusting device is provided on the manifold bypass pipeline (5); a liquid level gauge is provided in the hot well tank (1), and the control system is electrically connected to the liquid level gauge, the adjusting device, and the drainage pump system (3) respectively; the drainage pump system (3) includes at least three drainage pumps arranged in parallel, namely drainage pump one (301), drainage pump two (302), and drainage pump three (303). Among them, drainage pump one (301) and drainage pump two (302) are intermittent operation water pumps, and drainage pump three (303) is a standby water pump; five liquid level values are set in sequence from bottom to top in the hot well tank (1). The liquid level value of liquid level one to the liquid level value of liquid level five increases in sequence. The liquid level value of liquid level five is the opening value of drainage pump three (303), the liquid level value of liquid level four is the starting value of drainage pump two (302), the liquid level value of liquid level three is the stopping value of drainage pump two (302), the liquid level value of liquid level two is the starting value of drainage pump one (301), and the liquid level value of liquid level one is the stopping value of drainage pump one (301).

2. The hot well tank liquid level regulating device according to claim 1, characterized in that: The adjusting device includes manual control valve one (6), a cut-off valve (7), and manual control valve two (8). Manual control valve one (6) and manual control valve two (8) are respectively located at both ends of the cut-off valve (7).

3. The hot well tank liquid level regulating device according to claim 1, characterized in that: The manifold bypass pipeline (5) is an L-shaped pipeline.

4. The hot well tank liquid level regulating device according to claim 1, characterized in that: The outlet of the hot well tank bypass return pipeline (9) is connected to the return port at the top of the hot well tank (1).

5. The hot well tank liquid level regulating device according to claim 2, characterized in that: The cut-off valve (7) is a pneumatic or electric butterfly valve.

6. The hot well tank liquid level regulating device according to claim 1, characterized in that: The hot well tank (1) is fixed to the ground through brackets.

7. The hot well tank liquid level regulating device according to claim 1, characterized in that: The hot well tank bypass return pipeline (9) includes a vertical section, a corner section, and a horizontal section. The vertical section is connected to the horizontal section through the corner section. The corner section is an arc, and the horizontal section is lower than the bottom end of the hot well tank (1).

8. The method for regulating the liquid level of the hot well tank of the hot well tank liquid level regulating device according to any one of claims 1-7, characterized in that: The specific steps are as follows: The cut-off valve (7) in the adjusting device opens when the water level drops to a certain set liquid level before the stopping liquid level of drainage pump two (302). At this time, part of the turbid circulating water in the drainage manifold (4) will flow back into the hot well tank (1) along the manifold bypass pipeline (5) and the hot well tank bypass return pipeline (9), so that the water level in the hot well tank (1) rises. When it rises to a certain set liquid level before the starting liquid level of drainage pump three (303), the cut-off valve (7) is closed. At this time, the water level in the hot well tank (1) will drop again until the set liquid level at which the cut-off valve (7) opens. In this way, the water level in the hot well tank (1) is in dynamic balance.

9. The method for regulating the liquid level of the hot well tank according to claim 8, characterized in that: When the cut-off valve (7) cannot be opened due to a fault, under the original working mode of the water pumps, the balance of the water level in the hot well tank is achieved by starting and stopping drainage pump two (302).

Images