Closed circulating water pressure-stabilizing water supplementing system

Abstract

The utility model relates to a closed circulating water pressure-stabilizing water replenishing system, and belongs to the technical field of circulating cooling water equipment. According to the technical scheme, a desalting water pool (1) is connected with a water inlet pipeline at the bottom of a surge tank (4) through a make-up pump set (2) and an electric make-up valve (3), a water outlet pipeline at the bottom of the surge tank (4) is connected with an inlet pipeline of a circulating water pump set (13), and the circulating water pump set (13), equipment to be cooled (16) and an air cooler (17) form a closed loop. The pressure stabilizing device has the advantages that the pressure stabilizing tank and accessory devices of the pressure stabilizing tank are used for keeping the pressure of circulating water stable under the water supplementing condition of a closed circulating water system, continuous operation of the circulating water system can be guaranteed through the accident bypass valve under the fault or accident state of the pressure stabilizing tank or a nitrogen pressure stabilizing system, and safe production is guaranteed.

Description

Technical Field

[0001] The utility model relates to a closed circulating water pressure-stabilizing water replenishing system, belonging to the technical field of circulating cooling water equipment. Background Art

[0002] In the process of metallurgy, equipment manufacturing and other industrial production, a large amount of process cooling water is used to cool down metallurgical products. The process cooling water system is generally divided into two types: open system and closed system. The open system generally uses industrial production water supplied by the water company as the water source, which can be used as industrial water after simple treatment. It is often used in industrial turbid ring cooling water system. The closed system generally uses demineralized water as industrial cooling water. The demineralized water uses reverse osmosis filters and other devices to remove suspended matter, colloids and inorganic cations, anions and other impurities in the water. The advantages are less impurities and high water purity, which can ensure that the water quality in the closed system meets the standards and the heat exchange tube bundle is not blocked. It is generally used in industrial clean ring cooling water systems.

[0003] The circulating water pump of the commonly used closed circulating water system uses a variable frequency motor as the water pump power, and the frequency of the frequency converter is automatically or manually adjusted according to the system pressure to ensure the stability of the system pressure. At the same time, it is equipped with water replenishment devices such as a water replenishment tank and a water replenishment pump to replenish the system. However, in actual application, when the system is replenished with water, the water replenishment pump is started, the pressure of the circulating water system increases, and the circulating water pump frequency converter is not adjusted in time or over-adjusted. The pressure of the circulating water system is often unstable, resulting in reduced cooling effect or over-cooling of metallurgical products, which may cause peeling of the product surface or cracks inside the product, seriously affecting product quality and causing losses to the company. Utility Model Content

[0004] The utility model aims to provide a closed circulating water pressure-stabilizing and water-making system, which can maintain the circulating water pressure stable during water making up by utilizing a pressure-stabilizing tank and its accessory devices, and can also ensure the continuous operation of the circulating water system by utilizing an accident bypass valve when the pressure-stabilizing tank or the nitrogen pressure-stabilizing system fails or an accident occurs, thereby ensuring safe production. At the same time, since the nitrogen inside the pressure-stabilizing tank has a certain pressure, the water supply at the inlet of the circulating water pump maintains a certain pressurization effect, and the motor frequency is reduced by a frequency converter to reduce the power load of the circulating water pump group, thereby saving electric energy, creating benefits for the company, and effectively solving the above-mentioned problems existing in the background technology.

[0005] The technical scheme of the utility model is: a closed circulating water pressure-stabilizing water supply system, comprising a desalted water tank, a water supply pump group, an electric water supply valve, a pressure-stabilizing tank, a circulating water pump group, equipment to be cooled and an air cooler, wherein the front end of the water supply pump group is connected to the water suction port of the desalted water tank through a pipeline, and the rear end of the water supply pump group is connected to the front end of the electric water supply valve through a pipeline; a water inlet pipeline is provided at the bottom of the pressure-stabilizing tank, which is connected to the rear end of the electric water supply valve, and a water outlet pipeline is also provided at the bottom of the pressure-stabilizing tank, which is connected to the inlet pipeline of the circulating water pump group; the outlet main pipe of the circulating water pump group is connected to the equipment to be cooled through a pipeline, the rear end of the equipment to be cooled is connected to the air cooler through a pipeline, and the rear end of the air cooler is connected to the inlet pipeline of the circulating water pump group through a pipeline, so as to form a closed loop.

[0006] The top of the pressure regulating tank is connected to the rear end of the air supply regulating valve and the front end of the exhaust regulating valve through two pipelines respectively. The front end of the air supply regulating valve is connected to the nitrogen inlet through a pipeline, the rear end of the exhaust regulating valve is connected to the outdoor nitrogen discharge port, and the rear end of the air supply regulating valve is connected to the front end of the exhaust regulating valve.

[0007] An electric water outlet valve and a check valve are provided between the water outlet pipeline of the pressure stabilizing tank and the inlet pipeline of the circulating water pump group.

[0008] An emergency bypass valve is provided between the rear end of the water replenishment pump group and the inlet pipeline of the circulating water pump group, and the two are connected to each other through a pipeline.

[0009] The pressure stabilizing tank is a pressure vessel. A nitrogen pressure transmitter, a guided wave radar water level gauge and a safety valve are arranged on the top of the pressure stabilizing tank. The safety valve is arranged on the pipeline between the pressure stabilizing tank and the outdoor nitrogen discharge port. An emergency drain valve is arranged at the bottom of the pressure stabilizing tank.

[0010] The body of the pressure-regulating tank is provided with a magnetic flap water level gauge, the upper and lower ends of the magnetic flap water level gauge are connected to the pressure-regulating tank through flanges respectively, and the magnetic flap water level gauge is provided with low alarm contacts and high alarm contacts at 25% and 75% of the height of the pressure-regulating tank respectively.

[0011] A circulating water pressure transmitter and a pipeline filter are provided between the circulating water pump group and the equipment to be cooled.

[0012] The beneficial effects of the utility model are as follows: by utilizing the pressure stabilizing tank and its accessory devices, the closed circulating water system can maintain the circulating water pressure stable under the condition of water replenishment, and the accident bypass valve can be used to ensure the continuous operation of the circulating water system in the case of failure or accident of the pressure stabilizing tank or the nitrogen pressure stabilizing system, thereby ensuring safe production; at the same time, since the nitrogen inside the pressure stabilizing tank has a certain pressure, the water supply at the inlet of the circulating water pump maintains a certain pressurization effect, and the motor frequency is reduced by the frequency converter to reduce the operating power load of the circulating water pump group, thereby saving electricity and creating benefits for the company. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1It is a structural schematic diagram of the utility model;

[0014] In the figure: desalted water pool 1, water supply pump group 2, electric water supply valve 3, pressure regulating tank 4, magnetic flap water level gauge 5, low alarm contact 5-1, high alarm contact 5-2, nitrogen pressure transmitter 6, guided wave radar water level gauge 7, safety valve 8, emergency drain valve 9, emergency bypass valve 10, electric outlet valve 11, check valve 12, circulating water pump group 13, circulating water pressure transmitter 14, pipeline filter 15, equipment to be cooled 16, air cooler 17, air supply regulating valve 18, exhaust regulating valve 19, nitrogen inlet 20, outdoor nitrogen discharge port 21. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solution and advantages of the utility model implementation case clearer, the technical solution in the implementation case of the utility model will be clearly and completely described in combination with the drawings in the implementation case. Obviously, the implementation case described is a small part of the implementation case of the utility model, rather than all the implementation cases. Based on the implementation case in the utility model, all other implementation cases obtained by ordinary technicians in this field without making creative work are within the protection scope of the utility model.

[0016] A closed circulating water pressure-stabilizing and water-making system comprises a desalted water tank 1, a water-making pump group 2, an electric water-making valve 3, a pressure-stabilizing tank 4, a circulating water pump group 13, equipment to be cooled 16 and an air cooler 17, wherein the front end of the water-making pump group 2 is connected to the water suction port of the desalted water tank 1 through a pipeline, and the rear end of the water-making pump group 2 is connected to the front end of the electric water-making valve 3 through a pipeline; a water inlet pipeline is provided at the bottom of the pressure-stabilizing tank 4, which is connected to the rear end of the electric water-making valve 3; a water outlet pipeline is also provided at the bottom of the pressure-stabilizing tank 4, which is connected to the inlet pipeline of the circulating water pump group 13; the outlet main pipe of the circulating water pump group 13 is connected to the equipment to be cooled 16 through a pipeline, the rear end of the equipment to be cooled 16 is connected to the air cooler 17 through a pipeline, and the rear end of the air cooler 17 is connected to the inlet pipeline of the circulating water pump group 13 through a pipeline, so as to form a closed loop.

[0017] The top of the pressure-surge tank 4 is connected to the rear end of the air supply regulating valve 18 and the front end of the exhaust regulating valve 19 through two pipelines, the front end of the air supply regulating valve 18 is connected to the nitrogen inlet 20 through a pipeline, the rear end of the exhaust regulating valve 19 is connected to the outdoor nitrogen discharge port 21, and the rear end of the air supply regulating valve 18 is connected to the front end of the exhaust regulating valve 19.

[0018] An electric water outlet valve 11 and a check valve 12 are provided between the water outlet pipe of the pressure stabilizing tank 4 and the inlet pipe of the circulating water pump group 13 .

[0019] An emergency bypass valve 10 is provided between the rear end of the water replenishment pump group 2 and the inlet pipeline of the circulating water pump group 13, and the two are connected to each other through a pipeline.

[0020] The pressure stabilizing tank 4 is a pressure vessel. A nitrogen pressure transmitter 6, a guided wave radar water level gauge 7 and a safety valve 8 are arranged on the top of the pressure stabilizing tank 4. The safety valve 8 is arranged on the pipeline between the pressure stabilizing tank 4 and the outdoor nitrogen discharge port 21; an emergency drain valve 9 is arranged at the bottom of the pressure stabilizing tank 4.

[0021] The body of the pressure-stabilizing tank 4 is provided with a magnetic flap water level gauge 5, the upper and lower ends of which are connected to the pressure-stabilizing tank 4 through flanges respectively, and the magnetic flap water level gauge 5 is provided with a low alarm contact 5-1 and a high alarm contact 5-2 at 25% and 75% of the height of the pressure-stabilizing tank 4 respectively.

[0022] A circulating water pressure transmitter 14 and a pipeline filter 15 are provided between the circulating water pump group 13 and the equipment to be cooled 16 .

[0023] In practical applications, the daily water level control of the surge tank 4 is controlled by the guided wave radar water level gauge 7, and the low alarm contact 5-1 and the high alarm contact 5-2 of the magnetic flap water level gauge 5 serve as interlocking control backup devices to ensure safety of the surge tank 4 when the guided wave radar water level gauge 7 fails.

[0024] Assuming normal production status, the water level in the surge tank 4 is about 50%, the water supply pump group 2 is not started, the electric water outlet valve 11 is normally open, and the electric water supply valve 3, the emergency drain valve 9 and the emergency bypass valve 10 are closed. The surge tank 4 monitors the changes in the pressure in the tank through the nitrogen pressure transmitter 6, and feeds back the pressure signal to the PLC. The PLC controls the continuous adjustment of the air supply regulating valve 18 and the exhaust regulating valve 19 through the PID control function to maintain the pressure in the tank at about the set value of 0.35MPa. When the guided wave radar water level meter 7 monitors the water level to drop to 40%, the water level signal is fed back to the PLC, and the PLC interlocks to start the single pump of the water supply pump group 2 for water supply, and the start signal of the water supply pump group 2 interlocks the electric water supply valve 3 to open synchronously. At this time, the water level in the pressure-stabilizing tank 4 rises, and the nitrogen is compressed, causing the pressure in the pressure-stabilizing tank 4 to gradually increase. The pressure signal is fed back to the PLC, and the PLC continuously controls the exhaust regulating valve 19 to increase the opening, and the air supply regulating valve 18 to decrease or even close the opening, so that the pressure in the pressure-stabilizing tank 4 is maintained at around 0.35MPa. After the water level rises to 65%, the water supply pump group 2 stops pumping, and the stop signal of the water supply pump group 2 interlocks the electric water supply valve 3 to close synchronously.

[0025] When the water replenishment of the single pump of the water replenishment pump group 2 is insufficient due to a small amount of leakage in the circulating water system, the water level of the surge tank 4 is reduced to 30%. At this time, the two pumps of the water replenishment pump group 2 are running at the same time to meet the water replenishment requirements. After the water level rises to 65%, the water replenishment pump group 2 stops pumping, and the stop signal interlocking electric water replenishment valve 3 of the water replenishment pump group 2 is closed synchronously. When the two pumps of the water replenishment pump group 2 are running at the same time and still cannot meet the water replenishment requirements of the surge tank 4, the water level of the surge tank 4 drops to 25%, and the low-reporting contact 5-1 of the guided wave radar water level gauge 7 and the magnetic flap water level gauge 5 simultaneously triggers the low water level alarm, and the electric water replenishment valve 3 and the electric water outlet valve 11 are closed through the PLC interlock, and the accident bypass valve 10 is opened at the same time. The water replenishment pump group 2 directly supplies desalted water to the circulating water system to prevent nitrogen from entering the circulating water system due to the low water level of the surge tank 4, causing cavitation.

[0026] When the water supply pump group 2 continues to supply water due to the pump failure of the water supply pump group 2, when the water level reaches 75%, the high alarm contact 5-2 of the guided wave radar water level gauge 7 and the magnetic flap water level gauge 5 simultaneously triggers the high water level alarm, and the emergency drain valve 9 is opened through the PLC interlock to drain water until the water level drops to 65%, and then the emergency drain valve 9 is closed. The purpose is to prevent the desalted water from entering the nitrogen pipeline due to the excessively high water level in the pressure regulating tank 4.

[0027] The utility model utilizes the PID technology in the PLC control system, and realizes the closed circulating water system to maintain the circulating water pressure stable under the condition of water replenishment through the pressure stabilizing tank 4 and its auxiliary devices. It can also use the accident bypass valve 10 to ensure the continuous operation of the circulating water system and ensure safe production when the pressure stabilizing tank 4 or the nitrogen pressure stabilizing system fails or has an accident. At the same time, since the nitrogen inside the pressure stabilizing tank 4 has a certain pressure, the water supply at the inlet of the circulating water pump maintains a certain pressurization effect, and the motor frequency is reduced by the frequency converter to reduce the operating power load of the circulating water pump group 13, thereby saving electricity and creating benefits for the company.

Claims

1. A closed circulating water pressure stabilizing water replenishment system, characterized by: The invention comprises a desalted water pool (1), a water supply pump group (2), an electric water supply valve (3), a pressure regulating tank (4), a circulating water pump group (13), equipment to be cooled (16) and an air cooler (17), wherein the front end of the water supply pump group (2) is connected to the water suction port of the desalted water pool (1) through a pipeline, and the rear end of the water supply pump group (2) is connected to the front end of the electric water supply valve (3) through a pipeline; a water inlet pipeline is provided at the bottom of the pressure regulating tank (4) and is connected to the rear end of the electric water supply valve (3); a water outlet pipeline is also provided at the bottom of the pressure regulating tank (4) and is connected to the inlet pipeline of the circulating water pump group (13); the outlet main pipe of the circulating water pump group (13) is connected to the equipment to be cooled (16) through a pipeline, the rear end of the equipment to be cooled (16) is connected to the air cooler (17) through a pipeline, and the rear end of the air cooler (17) is connected to the inlet pipeline of the circulating water pump group (13) through a pipeline, so as to form a closed loop.

2. A closed circulating water pressure stabilizing and water replenishing system according to claim 1, characterized in that: The top of the pressure regulating tank (4) is connected to the rear end of the air supply regulating valve (18) and the front end of the exhaust regulating valve (19) respectively through two pipelines; the front end of the air supply regulating valve (18) is connected to the nitrogen inlet (20) through a pipeline; the rear end of the exhaust regulating valve (19) is connected to the outdoor nitrogen discharge port (21); and the rear end of the air supply regulating valve (18) is connected to the front end of the exhaust regulating valve (19).

3. A closed circulating water pressure stabilizing and water replenishing system according to claim 1, characterized in that: An electric water outlet valve (11) and a check valve (12) are provided between the water outlet pipe of the pressure stabilizing tank (4) and the inlet pipe of the circulating water pump group (13).

4. A closed circulating water pressure stabilizing and water replenishing system according to claim 1, characterized in that: An emergency bypass valve (10) is provided between the rear end of the water replenishment pump group (2) and the inlet pipeline of the circulating water pump group (13), and the two are connected to each other via a pipeline.

5. A closed circulating water pressure stabilizing and water replenishing system according to claim 2, characterized in that: The pressure stabilizing tank (4) is a pressure vessel. A nitrogen pressure transmitter (6), a guided wave radar water level gauge (7) and a safety valve (8) are provided on the top of the pressure stabilizing tank (4). The safety valve (8) is arranged on a pipeline between the pressure stabilizing tank (4) and an outdoor nitrogen discharge port (21). An emergency drain valve (9) is provided on the bottom of the pressure stabilizing tank (4).

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