CN204281425U - A kind of marine circulating cooling system system water process regulator control system - Google Patents

Abstract

The utility model relates to the technical field of seawater circulating cooling water treatment, in particular to a water treatment control system for a seawater circulating cooling system, comprising a seawater circulating cooling system, a control cabinet (21) and a microcomputer management control system (22). The pipelines of the system are sequentially connected to the sump (5), the seawater circulation pump (6), the heat exchanger (10) and the seawater cooling tower (11). The outlet of the seawater circulation pump (6) is provided with a circulating water sewage system, and each system is connected to the flow, liquid level, conductivity monitoring instrument in the control cabinet and PLC, and the PLC is connected to the microcomputer system to realize unified management and control. The utility model can realize the automatic management and control of water replenishment, sewage discharge and chemical dosing of the seawater circulation cooling system, can effectively guarantee the water balance, concentration multiple control and water treatment effect of the seawater circulation cooling system, and ensure the safe and stable operation of the seawater circulation cooling system.

Description

A water treatment control system for a seawater circulation cooling system

technical field

The utility model relates to the technical field of seawater circulation cooling water treatment, and mainly relates to a water treatment control system of a seawater circulation cooling system.

Background technique

Seawater circulating cooling technology is an environmentally friendly new technology. After more than 30 years of development abroad, it has entered the stage of large-scale application. With the aggravation of the shortage of coastal water resources in my country and the maturity of seawater circulation cooling technology, coastal enterprises have gradually increased the use of seawater and invested in the construction of seawater circulation cooling projects. Among them, my country's coastal power plants have built more than 10 units with an installed capacity of more than 1000 MW, and there are no less than 10 units under construction or to be built.

Facing the urgent needs of coastal enterprises for seawater circulating cooling technology, my country's seawater circulating cooling technology has achieved major technological breakthroughs after more than ten years of continuous scientific and technological research, and has completed hundred-ton, thousand-ton, 10,000-ton, 100,000-ton Ton level demonstration project. And form a series of seawater treatment pharmaceutical products, basically have the technical conditions for large-scale promotion and application. In contrast, the research on water treatment management technology of seawater circulating cooling system is still weak and lagging behind. Both on-site technical monitoring and parameter adjustment control are still manual, and automatic control and computer management have not been realized. There is still a lot of uncertainty and randomness in the precision control, which poses a great hidden danger to the safe and stable operation of the seawater circulating cooling technology.

In order to solve the relevant problems in the on-site management of cooling water, the research and application in this area are very active at home and abroad. It mainly includes on-line monitoring of process parameters, automatic dosing, automatic sewage discharge, water balance control, etc. From a technical point of view, the technical application of water treatment management and control in fresh water circulating cooling systems at home and abroad has been basically mature, while there are few reports on the application in seawater cooling systems. Including the most advanced 3D-TRASAR management system developed by Nalco in the world, there is no precedent for seawater cooling system.

Utility model content

The technical problem solved by the utility model is: due to the high salt content of seawater, corrosive and scaling ions are much higher than that of fresh water, the control of the concentration multiple of seawater circulating water and the use of water treatment chemicals are very different from the prior art , some detection and monitoring technologies will be greatly disturbed or restricted in seawater systems. Therefore, on the existing basis, how to learn from the advanced experience at home and abroad, integrate the existing technology, combine the characteristics of seawater, optimize the design of the management and control system, realize the operation management of seawater circulating water treatment, and ensure the safe and stable operation of the seawater circulating cooling system. very urgent.

Aiming at the prior art, the utility model provides a water treatment control system of the seawater circulation cooling system, which realizes the automatic management and control of water replenishment, sewage discharge and drug dosing of the seawater circulation cooling system, and effectively guarantees the water balance, concentration ratio control and The water treatment effect ensures the safe and stable operation of the seawater circulating cooling system.

Specifically, for the deficiencies in the prior art, the utility model provides the following technical solutions:

A water treatment control system of a seawater circulation cooling system, comprising a seawater circulation cooling system, a control cabinet 21 and a microcomputer control system 22, characterized in that the pipelines of the seawater circulation cooling system are sequentially connected to a sump 5, a seawater circulation pump 6, a heat sink The exchanger 10 and the seawater cooling tower 11 are provided with a seawater replenishment system and a dosing system at the inlet of the sump 5, and a circulating water sewage system is provided at the outlet of the seawater circulation pump 6, and the seawater replenishment system, the dosing system and the circulating water sewage The systems are all equipped with flow, liquid level or conductivity measuring devices connected to the monitoring instruments of the control cabinet 21, and are all equipped with delivery pumps or electric valves connected with the programmable logic controller of the control cabinet 21.

Preferably, in the above-mentioned water treatment control system of the seawater circulation cooling system, each monitoring instrument of the control cabinet 21 is connected to a programmable logic controller, and the programmable logic controller is connected to the microcomputer management control system 22 through a bus.

Preferably, in the above-mentioned water treatment control system of the seawater circulation cooling system, the seawater replenishment system includes a frequency conversion seawater pump 1 connected to the seawater, a replenishment electric valve 2, a seawater replenishment flow meter 3 and a first liquid pump installed in the sump 5 The level sensor 4, the frequency conversion seawater pump 1 and the replenishment electric valve 2 are connected to the programmable logic controller of the control cabinet 21, the seawater replenishment flow meter 3 and the first liquid level sensor 4 are connected to the flow and liquid level of the control cabinet 21 Monitor instrumentation connections.

Preferably, in the water treatment control system of the above-mentioned seawater circulation cooling system, a sewage branch line and a return water branch connecting the seawater circulation pump outlet and the sump inlet are provided at the outlet of the seawater circulation pump 6, and the circulating water sewage system includes The seawater conductivity sensor 7 installed in the water branch, the blowdown electric valve 8 and the blowdown flow meter 9 installed in the blowdown branch line, the blowdown electric valve 8 is connected to the programmable logic controller of the control cabinet 21, and the seawater conductivity sensor 7 and sewage flow meter 9 are connected with the conductivity and flow monitoring instrument of control cabinet 21.

Preferably, in the water treatment control system of the seawater circulating cooling system, the dosing system includes a dosing system for seawater scale and corrosion inhibitors and a dosing system for seawater bacteria and algae inhibitors.

Preferably, in the above-mentioned seawater circulation cooling system water treatment control system, the seawater scale and corrosion inhibitor dosing system includes a first storage tank 13 with a second liquid level sensor 12 installed, a medicament delivery pump 14 and a metering pump installed 16 and the dosing tank 15 of the third liquid level sensor 17, the medicament delivery pump 14 and the metering pump 16 are connected with the programmable logic controller of the control cabinet 21, the second liquid level sensor 12 and the third liquid level sensor 17 is connected with the liquid level monitoring instrument of control cabinet 21.

Preferably, in the above-mentioned water treatment control system of the seawater circulation cooling system, the inlet of the chemical delivery pump 14 is connected to the first storage tank 13, and the outlet includes a first branch pipeline and a second branch pipeline, and the first branch pipeline is connected to the charging tank 13. The medicine tank 15 is connected, and the second branch pipeline merges with the outlet pipeline of the metering pump 16 and is jointly connected with the return water branch.

Preferably, in the above-mentioned water treatment control system of the seawater circulating cooling system, before the second branch pipeline at the outlet of the agent delivery pump 14 merges with the outlet pipeline of the metering pump 16, it is set to open in the concentration operation stage of the basic dosing, and in the normal operation stage. The closed first valve 14a is provided with a second valve 16a that is closed at the beginning of the basic dosing concentration operation stage and opened at the normal operation stage before the outlet line of the metering pump 16 merges with the second branch line.

Preferably, in the above-mentioned water treatment control system of the seawater circulating cooling system, the seawater bacteria and algae inhibitor dosing system includes a second storage tank 19 equipped with a fourth liquid level sensor 18 and a dosing pump 20, and the dosing pump 20 is connected to the programmable logic controller of the control cabinet 21, and the fourth liquid level sensor 18 is connected to the liquid level monitoring instrument of the control cabinet 21.

Preferably, in the above-mentioned water treatment control system of the seawater circulation cooling system, all flow measuring devices, liquid level measuring devices, conductivity measuring devices, delivery pumps and electric valves that are in direct contact with seawater, concentrated seawater or pharmaceuticals are all made of seawater-resistant Corrosion and acid-alkali-resistant materials, the pipeline is made of corrosion-resistant non-metallic engineering materials.

The beneficial effects of the utility model are: the utility model is designed according to the characteristics of the seawater itself to replenish water, discharge and dosing process of the seawater circulation cooling system, and realize the automatic management and control of the water balance, the concentration multiple and the dosing and sewage discharge of the seawater circulation cooling system, greatly Improve the system operation management level and control accuracy, guarantee the seawater circulating cooling water treatment effect, make the seawater circulating cooling technology more advantageous in terms of water saving, technology, economy, and marine environment, and bring my country's seawater circulating cooling technology to a new level , to provide strong technical support for large-scale industrial promotion and application.

Description of drawings

Figure 1 is a schematic diagram of the water treatment control system of the seawater circulation cooling system.

In the figure: 1. Frequency conversion seawater pump, 2. Electric water replenishment valve, 3. Seawater replenishment flow meter, 4. First liquid level sensor, 5. Reservoir, 6. Seawater circulation pump, 7. Seawater conductivity sensor, 8. Sewage electric valve, 9. Sewage flow meter, 10. Heat exchanger, 11. Seawater cooling tower, 12. Second liquid level sensor, 13. First storage tank, 14. Drug delivery pump, 14a. First valve, 15 .dosing tank, 16. metering pump, 16a. second valve, 17. third liquid level sensor, 18. fourth liquid level sensor, 19. second storage tank, 20. dosing pump, 21. control cabinet, 22. Microcomputer management control system.

Fig. 2 is the control situation of the concentration ratio of the seawater circulating cooling system in embodiment 1.

Fig. 3 is the variation of the concentration of seawater scale and corrosion inhibitors with time in Example 1.

detailed description

The utility model is based on the fact that the technical application in the water treatment management control of the fresh water circulation cooling system is basically mature in the prior art, but there are few application reports in the seawater cooling system. The inventor provides the utility model after diligent research. In a preferred embodiment, the seawater circulating cooling system at least includes a seawater replenishment system, a circulating water sewage system, a chemical dosing system, a sump, a seawater circulation pump, a heat exchanger, and a seawater cooling tower.

Among them, the water replenishment system is composed of a frequency conversion seawater pump on the water intake pipeline, a water replenishment electric valve, a seawater replenishment flowmeter, a liquid level sensor installed in the sump, and a pipeline. The frequency conversion seawater pump, the water replenishment electric valve and the PLC (programmable logic controller), the seawater replenishment flowmeter and liquid level sensor are connected to the corresponding flow and liquid level monitoring instruments in the control cabinet, and the corresponding instruments are then connected to the PLC.

Among them, the circulating water sewage system is composed of a seawater conductivity sensor installed in the return water branch after the seawater circulating pump, a sewage discharge electric valve installed in the sewage branch pipeline, a sewage discharge flowmeter and pipelines, and the sewage discharge electric valve is connected with the PLC in the control cabinet. The seawater conductivity sensor and the sewage flow meter are connected to the corresponding conductivity and flow monitoring instruments in the control cabinet, and the corresponding instruments are then connected to the PLC.

Among them, the dosing system includes the dosing system of seawater scale and corrosion inhibitors and seawater bacteria and algae inhibitors. The metering pump installed on the tank consists of a liquid level sensor and pipelines. The chemical delivery pump is connected to the storage tank and the dosing tank. The outlet of the metering pump is connected to the circulating water return branch, and the chemical is added to the sump, the metering pump and the control cabinet. PLC connection, the liquid level sensor is connected to the corresponding liquid level monitoring instrument in the control cabinet, and the corresponding instrument is connected to the PLC; Composed of pumps and pipelines, the dosing pump is connected to the storage tank to directly add the medicine to the sump through the dosing pipeline, the dosing pump is connected to the PLC in the control cabinet, and the liquid level sensor is connected to the corresponding liquid level monitoring instrument in the control cabinet. The corresponding instrument is then connected to the PLC.

The water balance and concentration ratio of the seawater circulation cooling system are controlled by adjusting the seawater replenishment volume, the sump level and the sewage volume. Monitor the conductivity of the circulating water, supplemented by regular correction of the concentration ratio of the chlorine meter, set the conductivity corresponding to the control concentration ratio N (1.5~3.0) as the control point, and set the conductivity change range as 100~5000us/cm , optimized to 500-3000us/cm, automatic control of the sewage electric valve, maintaining the concentration multiple of the seawater circulating cooling system in continuous and stable operation under the condition of N±0.2.

The dosing process of seawater treatment chemicals: when the seawater scale and corrosion inhibitors are concentrated and run after basic dosing, the liquid level of the seawater scale and corrosion inhibitor storage tanks is monitored by the liquid level sensor, and the chemical delivery pump is controlled in proportion to the system volume Dosing; seawater bacteria and algae inhibitors monitor the liquid level of the seawater bacteria and algae inhibitors storage tank through the liquid level sensor when the basic dosage starts to concentrate, and control the dosing pump to add in proportion to the system volume; seawater scale and corrosion inhibition In the normal operation stage, the agent is used to measure the sewage volume of circulating water by the sewage flowmeter, and the metering pump is controlled to automatically add proportionally according to the sewage volume; Calculate the amount of seawater algae inhibitor based on the concentration of each time, and control the automatic dosing of the dosing pump by monitoring the liquid level of the seawater algae inhibitor storage tank.

The microcomputer management control system of the water treatment control system of the seawater circulation cooling system is connected with the PLC in the control cabinet through the bus to realize the integrated control of the water treatment operation management of the seawater circulation cooling system.

All the sensors, flowmeters, electric valves involved in the water treatment control system of the seawater circulation cooling system, and the seawater, concentrated seawater, and components in direct contact with the chemicals are all made of seawater corrosion-resistant materials, acid and alkali resistant materials, and the chemical pipelines are made of corrosion-resistant materials. Non-metal engineering materials.

The utility model and its beneficial technical effects will be described in detail below in conjunction with the accompanying drawings and various embodiments.

Example 1

In a kind of preferred embodiment of the present utility model, comprise following structure:

As shown in Figure 1, the seawater circulation cooling system at least includes a seawater replenishment system (1-4), a sump 5, a seawater circulation pump 6, a heat exchanger 10, a seawater cooling tower 11, a circulating water sewage system (7-9), Dosing system (12-20).

As shown in Figure 1, the water replenishment system includes a frequency conversion seawater pump 1 on the water intake pipeline, a water replenishment electric valve 2, a seawater replenishment flow meter 3, a first liquid level sensor 4 installed in the sump 5 and pipelines, a frequency conversion seawater pump 1 and water replenishment The electric valve 2 is connected to the PLC in the control cabinet 21, the sea water replenishment flowmeter 3 and the first liquid level sensor 4 are connected to the corresponding flow and liquid level monitoring instruments in the control cabinet 21, and the corresponding instruments are connected to the PLC, and the PLC communicates with the microcomputer through the bus The management and control system 22 is connected, and the amount of seawater replenishment is monitored by the first liquid level sensor 4 to monitor the liquid level of the sump 5, and the electric valve 2 and the frequency conversion seawater pump 1 are adjusted and controlled.

As shown in Figure 1, the circulating water sewage system includes a seawater conductivity sensor 7 installed in the backwater branch after the seawater circulating pump 6, a sewage electric valve 8 installed in the sewage branch line, a sewage flow meter 9 and pipelines, and the sewage electric valve 8 is connected to the PLC in the control cabinet 21, the seawater conductivity sensor 7 and the sewage flowmeter 9 are connected to the corresponding conductivity and flow monitoring instruments in the control cabinet 21, and the corresponding instruments are connected to the PLC, and the PLC manages the control system 22 through the bus and the microcomputer Connection, the concentration ratio is regularly corrected by monitoring the conductivity of the circulating water and supplemented by the analysis of the concentration ratio of the chlorine meter, such as setting the conductivity 60000us/cm corresponding to the control concentration ratio N=2.0 as the control point, and setting the conductivity change interval 2000us/cm, when the conductivity of the circulating water exceeds 60000us/cm, the sewage electric valve 8 is automatically opened, and when the conductivity of the circulating water is lower than 58000us/cm, the sewage electric valve 8 is automatically closed, and the concentration factor of the seawater circulation cooling system is maintained at 2 Continuous and stable operation under the condition of ±0.2.

As shown in Figure 1, the seawater scale and corrosion inhibitor dosing system includes a first storage tank 13, a second liquid level sensor 12 installed on the first storage tank 13, a dosing tank 15, and a metering device installed on the dosing tank 15. The pump 16, the third liquid level sensor 17 and the pipeline, the medicament delivery pump 14 is connected to the first storage tank 13 and the dosing tank 15, the outlet of the metering pump 16 is connected to the circulating water return branch, and the medicament is added to the sump 5 for metering. The pump 16 is connected to the PLC in the control cabinet 21, the second liquid level sensor 12 and the third liquid level sensor 17 are connected to the corresponding liquid level monitoring instruments in the control cabinet 21, and the corresponding instruments are connected to the PLC, and the PLC is managed and controlled by the microcomputer through the bus The system 22 is connected; the seawater bacteria and algae inhibitor dosing system includes the second storage tank 19, the fourth liquid level sensor 18 installed on the second storage tank 19, the dosing pump 20 and the pipeline, and the dosing pump 20 is connected to the second storage tank 19. Dosing the medicament directly into the sump 5 through the dosing pipeline, the dosing pump 20 is connected to the PLC in the control cabinet 21, the fourth liquid level sensor 18 is connected to the corresponding liquid level monitoring instrument in the control cabinet 21, and the corresponding instrument is then Connect with PLC, PLC is connected with microcomputer management control system 22 through bus line. Dosing process of sea water treatment chemicals:

As shown in Figure 1, when the seawater scale and corrosion inhibitors start concentrated operation after basic dosing, the liquid level of the first chemical storage tank 13 is monitored by the second liquid level sensor 12, and the chemical delivery pump 14 is controlled, which is proportional to the system volume Dosing; when the seawater bacteria and algae inhibitor starts to concentrate and run after the basic dosing, the liquid level of the second storage tank 19 of the agent is monitored through the fourth liquid level sensor 18, and the dosing pump 20 is controlled to dosing in proportion to the system volume; seawater During the normal operation stage, the scale and corrosion inhibitors measure the sewage volume of circulating water through the sewage discharge flow meter 9, control the metering pump 16, and automatically add proportionally according to the sewage volume; The drug cycle (frequency), the amount of seawater bacteria and algae inhibitors are calculated each time the concentration is added, and the drug dosing pump 20 is controlled to automatically add the drug by monitoring the liquid level of the second storage tank 19 of the drug. The relationship between the liquid level of the monitoring agent and the dosage of seawater scale and corrosion inhibitors or algae inhibitors is as follows: Dosing amount of agent = liquid level difference of storage tank before and after adding × cross-sectional area of storage tank × agent density.

As shown in Figure 1, all the sensors, flow meters, electric valves used in the water treatment management and control system of the seawater circulation cooling system are in direct contact with seawater, concentrated seawater, and chemicals. Stainless steel, titanium alloy, polytetrafluoroethylene, etc., and the chemical pipeline is made of corrosion-resistant non-metallic engineering materials, such as ABS, PVC, UPVC and other engineering plastics.

Engineering Example

The utility model is further illustrated below in conjunction with the example of my country's first chemical industry Tianjin Tanggu seawater circulation cooling project.

(1) Water balance control parameters of seawater circulating cooling system

The seawater circulating water volume is 2500m ³ /h, the system volume is 800m ³ , the concentration ratio is controlled at 2.0, the evaporation loss is about 40m ³ /h, the sewage loss is about 40m ³ /h, the supplementary water volume is about 80m ³ /h, and the wind blowing loss is negligible.

(2) Control mode of seawater circulation cooling system

The water supply system monitors the water level of the sump, and the high and low level alarm control; the sewage system monitors the conductivity of the circulating water and automatically controls the electric valve switch; the dosing system monitors the sewage volume and automatically adds scale and corrosion inhibitors in proportion; the bacteria and algae inhibitors are based on the volume of the system Intermittent automatic dosing every 3 days.

(3) Process normal control index of seawater circulating cooling system

The concentration factor is 2±0.2, the conductivity is 50,000-60,000 us/cm (display), the sewage conductivity setting interval difference is 100-300us/cm, the output frequency of the flow transmitter is 1 time/10L-20L sewage, and the metering pump Stroke and speed are set at 40% to 80%.

(4) Operation of water treatment in the seawater circulation cooling system

The control of the concentration multiple of this seawater circulating cooling project is mainly through the continuous monitoring of the conductivity of the circulating water in the system, and at the same time, the method of random analysis and detection of chlorine radicals is used to correct the conductivity meter alarm setting point (pollution discharge point) and alarm interval (difference in the conductivity control interval) ), control the automatic opening or closing of the electric valve to maintain the stable operation of the system concentration multiple, and realize water balance control in combination with water replenishment control and sewage discharge control.

The seawater circulating cooling project was successfully switched from the original fresh water circulating cooling system to the seawater circulating cooling system. The field test results of continuous inspection and monitoring for nearly 100 days during the test are shown in Figure 2. In order to ensure the safe operation of the system, according to the site conditions, the concentration ratio is controlled to increase slowly at the initial stage of the concentration operation, and then transition to normal operation after a week of low concentration ratio operation. The field operation results show that the concentration ratio of the system in this seawater circulation cooling project is stable, basically maintained at 1.8-2.2, and the electrical conductivity is maintained at around 55000us/cm (shown), which is controlled within the expected range of 50,000-60,000us/cm , The sewage conductivity setting interval difference is 100-200us/cm, which is also within the expected range of 100-300us/cm. The operation results further show that it is effective and feasible to continuously monitor the conductivity of circulating water, realize automatic sewage discharge, and control the concentration multiple of the system, which provides a strong guarantee for the safe and stable operation of the system.

Seawater chemical water treatment is the key core technology of seawater circulating cooling technology, mainly to solve the problems of corrosion, scaling and fouling organisms in the system. "Three points of medicine and seven points of management", it can be seen that advanced system regulation technology is an important guarantee to ensure the effect of water treatment. In this seawater circulation cooling automatic dosing system, water treatment chemicals are added in proportion to the amount of sewage to maintain the normal concentration of the system and meet the actual operation requirements. The field test results of continuous monitoring for nearly 100 days during the test are shown in Figure 3. According to the experimental research plan formulated as expected, the system enters the concentrated operation stage, and the scale and corrosion inhibitors are operated for about 10 days at a high dose. When the concentration ratio reaches about 2.0, it enters the normal operation stage. According to the actual operation situation on site, the control indicators of each chemical agent have been adjusted accordingly in different periods, but the chemical dosing is added in proportion to the sewage, so the chemical concentration is always close to the control index.

(5) Water treatment operation effect of seawater circulating cooling system:

Carbon steel corrosion control: the average corrosion rate of the 33-day test piece is 0.0331mm/a, the average corrosion rate of the 83-day test piece is 0.0197mm/a, and the average corrosion rate of the 83-day test tube is 0.0188mm/a;

Scaling control in sea water: The thermal resistance of fouling in the year of monitoring heat exchanger test is about 1.5×10-4m ² K/W, and the measured value of adhesion speed in 83 days is 10.59mcm, which belongs to the "very good" range in the evaluation level;

Seawater bacteria and algae control: the number of heterotrophic bacteria <5×10 ⁵ cfu/mL (summer), <1×10 ⁵ cfu/mL (winter), the number of iron bacteria <300cfu/mL, the number of sulfate-reducing bacteria < 100cfu/mL.

Obviously, the seawater circulating cooling water treatment has a good operation effect, and the indicators of seawater corrosion, scaling, and bacteria and algae control have all reached the technical indicators specified in the "Code for Design of Seawater Circulating Cooling Water Treatment" (GB/T 23248-2009), a breakthrough The "Code for Design of Industrial Circulating Cooling Water Treatment" (GB 50050-2007) water quality standard required by the fresh water circulating cooling system requires restricted areas. In my country, the technological innovation of replacing fresh water with seawater as industrial circulating cooling water has been realized.

The above is a detailed description of the utility model in conjunction with Fig. 1 and engineering examples, but the utility model is not limited to the above-mentioned specific implementation, and the above-mentioned specific implementation is only illustrative, rather than restrictive. Under the enlightenment of the utility model, those skilled in the art can also make many deformations without departing from the gist of the utility model, and these all belong to the protection scope of the utility model.

Claims (10)

1. a seawater circulation cooling system water treatment control system, comprising seawater circulation cooling system, control cabinet (21) and microcomputer management control system (22), it is characterized in that, the pipeline of described seawater circulation cooling system is connected with sump successively (5), seawater circulation pump (6), heat exchanger (10) and seawater cooling tower (11), are provided with seawater replenishment system and dosing system at the inlet of sump (5), at the outlet of seawater circulation pump (6) A circulating water sewage system is provided, and the seawater replenishment system, the dosing system and the circulating water sewage system are all equipped with flow, liquid level or conductivity measuring devices connected to the monitoring instrument of the control cabinet (21), and are equipped with The delivery pump or electric valve connected to the programmable logic controller of the control cabinet (21). 2. The seawater circulation cooling system water treatment control system according to claim 1, wherein, each monitoring instrument of the control cabinet (21) is connected with a programmable logic controller, and the programmable logic controller is connected with a microcomputer through a bus The management control system (22) is connected. 3. The seawater circulating cooling system water treatment control system according to claim 1 or 2, wherein the seawater replenishment system comprises a frequency conversion seawater pump (1) connected to seawater, a replenishment electric valve (2), a seawater replenishment flowmeter (3) and the first liquid level sensor (4) installed in the sump (5), the frequency conversion seawater pump (1) and water supplement electric valve (2) are connected with the programmable logic controller of the control cabinet (21) , the seawater replenishment flow meter (3) and the first liquid level sensor (4) are connected with the flow and liquid level monitoring instruments of the control cabinet (21). 4. The seawater circulation cooling system water treatment regulation and control system according to claim 1 or 2, wherein, at the outlet of the seawater circulation pump (6) is provided with a sewage discharge branch line and a return water branch connecting the seawater circulation pump outlet and the sump inlet , the circulating water sewage system includes a seawater conductivity sensor (7) installed in the backwater branch, a blowdown electric valve (8) and a blowdown flowmeter (9) installed in the blowdown branch line, and the blowdown electric valve (8) It is connected with the programmable logic controller of the control cabinet (21), and the seawater conductivity sensor (7) and the blowdown flow meter (9) are connected with the conductivity and flow monitoring instrument of the control cabinet (21). 5. The water treatment control system of the seawater circulating cooling system according to claim 1 or 2, wherein the dosing system comprises a dosing system for seawater scale and corrosion inhibitors and a dosing system for seawater bacteria and algae inhibitors. 6. The seawater circulating cooling system water treatment control system according to claim 5, wherein the seawater scale and corrosion inhibitor dosing system comprises a first storage tank (13) equipped with a second liquid level sensor (12) , medicament delivery pump (14) and the dosing tank (15) that metering pump (16) and the 3rd liquid level sensor (17) are installed, described medicament delivery pump (14) and metering pump (16) and control cabinet ( 21), the second liquid level sensor (12) and the third liquid level sensor (17) are connected with the liquid level monitoring instrument of the control cabinet (21). 7. The seawater circulation cooling system water treatment control system according to claim 6, wherein the inlet of the medicament delivery pump (14) is connected to the first storage tank (13), and the outlet includes the first branch pipeline and the second branch pipeline. pipeline, the first branch pipeline is connected with the dosing tank (15), and the second branch pipeline merges with the outlet pipeline of the metering pump (16) and is jointly connected with the return water branch. 8. The water treatment control system of the seawater circulation cooling system according to claim 7, wherein, before the second branch pipeline at the outlet of the medicament delivery pump (14) merges with the outlet pipeline of the metering pump (16), a basic dosing The first valve (14a), which is opened at the beginning of the enrichment operation stage and closed at the normal operation stage, is set on the outlet line of the metering pump (16) before it merges with the second branch pipeline. Stage open second valve (16a). 9. The seawater circulating cooling system water treatment control system according to claim 5, wherein the seawater bacteria and algae inhibitor dosing system comprises a second storage tank (19) equipped with a fourth liquid level sensor (18) and A dosing pump (20), the dosing pump (20) is connected with the programmable logic controller of the control cabinet (21), and the fourth liquid level sensor (18) is connected with the liquid level monitoring instrument of the control cabinet (21) connect. 10. The seawater circulating cooling system water treatment control system according to claim 1, wherein all flow measuring devices, liquid level measuring devices, conductivity measuring devices, delivery pumps and electric valves are in direct contact with seawater, concentrated seawater or medicaments The parts are made of seawater corrosion-resistant or acid-alkali-resistant materials, and the pipelines are made of corrosion-resistant non-metallic engineering materials.