Circulating water system of petrochemical enterprise

Abstract

The utility model belongs to the technical field of cooling water circulation system, disclose a kind of circulating water system of petroleum chemical industry, including sequentially connected pump group, water supply pipeline, heat exchange equipment group, backwater pipeline, cooling equipment, pool mechanism and the circulating water system formed by the pump group;The heat exchange equipment group includes low pressure equipment group and high pressure equipment group, and the pipeline pump of secondary pressurization is high pressure equipment group to promote water pressure, so that the rated pressure of the pump group is the 70%-80% of the maximum water pressure required by the heat exchange equipment group;Loop pressure reducing orifice plate device is provided on backwater pipeline;At least two high pressure heat exchangers are connected in series on the branch close to pump.The utility model has the characteristics of partial pressure water supply and gradient utilization, can reduce energy waste, save cost, and is suitable for application in the cooling water system of petrochemical industry.

Description

Technical Field

[0001] This utility model belongs to the technical field of cooling water circulation systems, and relates to a circulating water system for petrochemical enterprises. Background Technology

[0002] In petrochemical enterprises, circulating water systems play a crucial role in providing cooling and other services to water-using equipment in various production units. However, existing circulating water system designs have several shortcomings: First, the head of the circulating water pumps is determined based on the water-using equipment at the most unfavorable point in the entire plant, resulting in excessively high free heads for other water-using equipment and energy waste. Second, previously, all circulating water pumps were industrial frequency pumps. Because the circulating water system was designed based on meteorological data from the hottest three months of the past five years, supply exceeds demand during winter operation, leading to energy waste. Third, the circulating water supply network lacks necessary throttling and flow monitoring measures, resulting in severe "water grabbing" in favorable supply areas and actual temperature differences between supply and return water deviating from design values, affecting system operating efficiency. These problems make the existing circulating water systems in petrochemical enterprises inefficient and energy-intensive, urgently requiring improvement. Utility Model Content

[0003] In order to overcome the shortcomings of the prior art, this utility model provides a circulating water system for petrochemical enterprises. The purpose is to optimize the supply pressure and flow rate of the circulating water pump set, and reduce the energy consumption of the circulating water system and improve the operating efficiency through "pressure-divided water supply" and "gradient utilization".

[0004] To achieve the above objectives, this utility model provides the following technical solution: a circulating water system for a petrochemical enterprise, comprising a pump group, a water supply pipeline, a heat exchange equipment group, a return water pipeline, a cooling device, a water tank structure, and the pump group connected in sequence to form a circulating water system; the heat exchange equipment group includes a low-pressure equipment group and a high-pressure equipment group, both connected in parallel between the water supply pipeline and the return water pipeline, with the low-pressure equipment group located between the high-pressure equipment group and the pump group; a pipeline pump for secondary pressurization is installed on the water supply pipeline between the low-pressure equipment group and the high-pressure equipment group; in the low-pressure equipment... A circuit pressure reducing orifice plate device is installed on the return water pipe between the pump group and the high-pressure equipment group; the low-pressure equipment group includes multiple low-pressure branches connected in series with low-pressure heat exchangers, each low-pressure branch is connected to the water supply pipe and the return water pipe at both ends respectively, and at least two low-pressure heat exchangers are connected in series on the low-pressure branch near the pump group; the high-pressure equipment group includes multiple high-pressure branches connected in series with high-pressure heat exchangers, each high-pressure branch is connected to the water supply pipe and the return water pipe at both ends respectively, and at least two high-pressure heat exchangers are connected in series on the high-pressure branch near the pipeline pump.

[0005] As a further optimization, the rated pressure of the pump set is 70%-80% of the maximum water pressure required by the heat exchange equipment set; the pipeline pump is a variable frequency pump, and its rated pressure is 20%-30% of the maximum water pressure required by the heat exchange equipment set; the pump set includes several fixed frequency pumps and several variable frequency pumps, and the rated flow rate output by all the fixed frequency pumps is 70%-80% of the maximum flow rate required by the heat exchange equipment set; the rated flow rate output by all the variable frequency pumps is 20%-30% of the maximum flow rate required by the heat exchange equipment set.

[0006] As a further optimization, a pressure reducing orifice plate device is provided on both the low-pressure branch and the high-pressure branch near the water supply pipeline.

[0007] As a further optimization, maintenance control valve assemblies and flow detectors are provided on the return water pipe between the low-pressure equipment group and the cooling equipment, and on the supply water pipe between the low-pressure equipment group and the pump group.

[0008] As a further optimization, each of the low-pressure branch and the high-pressure branch is equipped with a pressure sensor and a temperature sensor; the water supply pipe near the water outlet of the pump set is also equipped with the pressure sensor and the temperature sensor; the pressure sensor and the temperature sensor are both electrically connected to the control cabinet, and the control cabinet is electrically connected to the pump set and the pipeline pump, for controlling the pump set and the pipeline pump according to the collected pressure and temperature values.

[0009] Compared with existing technologies, the beneficial effects of this invention are as follows: By adopting a "divided pressure water supply" scheme, the pump set provides sufficient water pressure to cover the needs of low-pressure equipment, while providing secondary pressurization water supply to high-pressure equipment. This effectively reduces the high energy consumption problem of the unified water supply system, lowers energy waste, and reduces the equipment cost of the pump set. Utilizing a "gradient utilization" method, water-using equipment near the favorable water supply area is connected in series on branch lines, increasing the amount of reused water, improving the water reuse rate, and saving water resources. In summary, this system features divided pressure water supply and gradient utilization, reducing energy waste and saving costs, making it suitable for application in cooling water systems in the petrochemical industry. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the system structure of an embodiment of the present invention.

[0011] The correspondence between the technical features in the figure and the reference numerals is as follows: Pump group 1; Maintenance control valve assembly 11; Flow detector 12; Pressure sensor 13; Temperature sensor 14; Water supply pipeline 2; Heat exchange equipment group 3; Low-pressure equipment group 31; Low-pressure heat exchanger 311; Low-pressure branch 312; High-pressure equipment group 32; High-pressure heat exchanger 321; High-pressure branch 322; Branch pressure reducing orifice plate device 33; Return water pipeline 4; Cooling equipment 5; Water tank mechanism 6; Pipeline pump 7; Loop pressure reducing orifice plate device 8. Detailed Implementation

[0012] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some preferred embodiments of this utility model, and not all embodiments. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of this utility model, and are not intended to limit the protection scope of this utility model.

[0013] Example: Please refer to Figure 1 This utility model provides the following technical solution: a circulating water system for a petrochemical enterprise, comprising a pump group 1, a water supply pipeline 2, a heat exchange equipment group 3, a return water pipeline 4, a cooling equipment 5, a water tank mechanism 6, and the pump group 1 connected in sequence to form a circulating water system; wherein, the cooling equipment 5, the water tank mechanism 6, and the pump group 1 form a circulating water cooling area, which exchanges heat with the heat exchange equipment group 3 to cool and reduce the temperature of the heat exchange equipment group 3. The heat exchange equipment group 3 includes a low-pressure equipment group 31 and a high-pressure equipment group 32, both connected in parallel between the water supply pipe 2 and the return water pipe 4, with the low-pressure equipment group 31 located between the high-pressure equipment group 32 and the pump group 1. A pipeline pump 7 for secondary pressurization is installed on the water supply pipe 2 between the low-pressure equipment group 31 and the high-pressure equipment group 32. A loop pressure reducing orifice plate device 8 is installed on the return water pipe 4 between the low-pressure equipment group 31 and the high-pressure equipment group 32. The rated pressure of the pump group 1 is 70%-80% of the maximum water pressure required by the heat exchange equipment group 3. The pipeline pump 7 is a variable frequency pump, and its rated pressure is the maximum water pressure required by the heat exchange equipment group 3. The pressure is 20%-30% of the maximum water pressure; the low-pressure equipment group 31 includes multiple low-pressure branches 312 connected in series with low-pressure heat exchangers 311, each low-pressure branch 312 is connected to the water supply pipe 2 and the return water pipe 4 at both ends, and at least two low-pressure heat exchangers 311 are connected in series on the low-pressure branch 312 near the pump group 1; the high-pressure equipment group 32 includes multiple high-pressure branches 322 connected in series with high-pressure heat exchangers 321, each high-pressure branch 322 is connected to the water supply pipe 2 and the return water pipe 4 at both ends, and at least two high-pressure heat exchangers 321 are connected in series on the high-pressure branch 322 near the pipeline pump 7.

[0014] The working principle includes that by adopting the "pressure-dividing water supply" scheme, the water pressure of pump group 1 is sufficient to cover the demand of low-pressure equipment, and the water supply of high-pressure equipment group 32 is pressurized for a second time, which effectively reduces the high energy consumption problem of the unified water supply system of pump group 1, reduces energy waste, and also reduces the equipment cost of pump group 1.

[0015] By utilizing a "gradient utilization" method, water-using equipment located near the favorable water supply area is converted to series water supply on branch lines. This increases the amount of water reused, improves the water reuse rate, and saves water resources. Furthermore, the pressure in the return water pipe 4, after secondary pressurization by the pipeline pump 7, is increased. By installing a loop pressure-reducing orifice plate device 8, the outlet water pressure of the low-pressure equipment area is lowered, preventing obstruction of the water output from the low-pressure equipment. This ensures a more balanced and efficient flow in the return water pipe 4, delivering water more quickly to the cooling equipment 5 and improving cooling efficiency.

[0016] Even better, pump group 1 is divided into variable frequency pumps and fixed frequency pumps to improve the adjustment capability and adapt to different ambient temperatures in winter and summer. Pump group 1 includes several fixed frequency pumps and several variable frequency pumps. The rated flow rate output of all fixed frequency pumps is 70%-80% of the maximum flow rate required by the heat exchange equipment group 3; the rated flow rate output of all variable frequency pumps is 20%-30% of the maximum flow rate required by the heat exchange equipment group 3. The fixed frequency pumps are sufficient to cover the flow requirements in winter, and with the adjustment function of the variable frequency pumps, they can have a wider adjustment range, meeting the needs even under high-temperature conditions in summer. Furthermore, the combined use of fixed frequency pumps and variable frequency pumps reduces costs.

[0017] To reduce the high pressure of the water supply in the favorable water supply area and maintain the system head balance, pressure-reducing orifice plate devices 33 are provided on both the low-pressure branch 312 and the high-pressure branch 322, near the side of the water supply pipe 2. More preferably, such as Figure 1 The equipment on the left side of the low-pressure branch 312 and the high-pressure branch 322 mentioned above is a key target and should be monitored more closely. This branch is equipped with various monitoring devices such as pressure, temperature and flow, as well as regulating valves.

[0018] In a preferred embodiment, a maintenance control valve assembly 11 and a flow detector 12 are provided on the return water pipe 4 between the low-pressure equipment group 31 and the cooling equipment 5 and on the supply water pipe between the low-pressure equipment group 31 and the pump group 1, so as to facilitate maintenance and flow monitoring.

[0019] To enhance the system's monitoring capabilities, monitoring components are installed. Each of the low-pressure branch 312 and the high-pressure branch 322 is equipped with a pressure sensor 13 and a temperature sensor 14. The water supply pipe 2 near the water outlet of the pump set 1 is also equipped with the pressure sensor 13 and temperature sensor 14. Both the pressure sensor 13 and temperature sensor 14 are electrically connected to a control cabinet, which is electrically connected to the pump set 1 and the pipeline pump 7. The control cabinet is used to control the pump set 1 and the pipeline pump 7 based on the collected pressure and temperature values. The control of the pump set 1 may include controlling the number of fixed-frequency pumps and the power of the variable-frequency pumps. The control of the pipeline pump 7 may include the switching on / off state and the power of the pipeline pump 7.

[0020] The advantages of this embodiment are as follows: First, by adopting a "pressure-divided water supply" scheme, the circulating water pump group 1 is divided into variable frequency pumps and fixed frequency pumps, and secondary pressurization water supply is provided to the high-pressure water-using equipment, effectively reducing the high energy consumption problem of the unified water supply system and reducing energy waste. Second, by using a "gradient utilization" method, important water-using equipment with large heat exchange is managed and controlled, and water-using equipment with suitable conditions is converted to series water supply, increasing the amount of reused water, improving the water reuse rate, and saving water resources. Third, by using monitoring and adjustment components to monitor various parameters of the circulating water in real time, and adjusting relevant equipment based on the data, combined with structured modeling to determine the parameters of each piece of equipment, the optimized design and precise control of the circulating water system are realized, improving the system's operating efficiency and stability. Fourth, this system has a simple structure, is easy to install and maintain, and can effectively solve the problems existing in the circulating water systems of petrochemical enterprises.

[0021] In summary, this system features pressure-divided water supply and gradient utilization, which can reduce energy waste and save costs, making it suitable for use in cooling water systems in the petrochemical industry.

[0022] The parts of this utility model not described in detail are prior art; for those skilled in the art, the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The scope of this utility model is defined by the appended claims and their equivalents.

Claims

1. A circulating water system for a petrochemical enterprise, comprising a pump set (1), a water supply pipeline (2), a heat exchange equipment group (3), a return water pipeline (4), a cooling equipment (5), a water tank structure (6), and the pump set (1) connected in sequence to form a circulating water system; characterized in that: The heat exchange equipment group (3) includes a low-pressure equipment group (31) and a high-pressure equipment group (32) connected in parallel between the water supply pipe (2) and the return water pipe (4), and the low-pressure equipment group (31) is located between the high-pressure equipment group (32) and the pump group (1); a pipeline pump (7) for secondary pressurization is installed on the water supply pipe (2) between the low-pressure equipment group (31) and the high-pressure equipment group (32); a loop pressure reducing orifice plate device (8) is provided on the return water pipe (4) between the low-pressure equipment group (31) and the high-pressure equipment group (32); the low-pressure equipment group (31) includes multiple low-pressure heat exchangers (311) connected in series. The low-pressure branch (312) of the pump group (1) is connected to the water supply pipe (2) and the return pipe (4) at both ends, and at least two low-pressure heat exchangers (311) are connected in series on the low-pressure branch (312) near the pump group (1); the high-pressure equipment group (32) includes a plurality of high-pressure branch (322) connected in series with high-pressure heat exchangers (321), and at both ends of the high-pressure branch (322) are connected to the water supply pipe (2) and the return pipe (4) at both ends, and at least two high-pressure heat exchangers (321) are connected in series on the high-pressure branch (322) near the pipeline pump (7).

2. The petrochemical plant recirculating water system of claim 1, wherein: The rated output pressure of the pump set (1) is 70%-80% of the maximum water pressure required by the heat exchange equipment set (3); the pipeline pump (7) is a variable frequency pump, and its rated output pressure is 20%-30% of the maximum water pressure required by the heat exchange equipment set (3); the pump set (1) includes several fixed frequency pumps and several variable frequency pumps, and the rated flow rate output by all the fixed frequency pumps is 70%-80% of the maximum flow rate required by the heat exchange equipment set (3); the rated flow rate output by all the variable frequency pumps is 20%-30% of the maximum flow rate required by the heat exchange equipment set (3).

3. The petrochemical plant recirculating water system of claim 1, wherein: On both the low-pressure branch (312) and the high-pressure branch (322), a branch pressure reducing orifice plate device (33) is provided on the side near the water supply pipe (2).

4. The petrochemical plant recirculating water system of claim 1, wherein: Maintenance control valve assembly (11) and flow detector (12) are provided on the return water pipe (4) between the low-pressure equipment group (31) and the cooling equipment (5) and on the supply water pipe (2) between the low-pressure equipment group (31) and the pump group (1).

5. The petrochemical plant recirculating water system of claim 2, wherein: Each of the low-pressure branch (312) and the high-pressure branch (322) is equipped with a pressure sensor (13) and a temperature sensor (14); the water supply pipe (2) near the water outlet end of the pump group (1) is also equipped with the pressure sensor (13) and the temperature sensor (14); the pressure sensor (13) and the temperature sensor (14) are both electrically connected to the control cabinet, which is electrically connected to the pump group (1) and the pipeline pump (7) and is used to control the pump group (1) and the pipeline pump (7) according to the collected pressure and temperature values.

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