A steel plant wastewater recovery intelligent control system and a control method thereof

Abstract

The application discloses a steel plant wastewater recovery intelligent control system and relates to the technical field of wastewater recovery systems, solving the problem of a large amount of manpower consumption and a long reaction time to abnormal conditions in the prior art through management means. The system comprises field instrument devices installed in each wastewater collection tank, the instrument data tested by the field instrument devices include flow and chloride ion concentration, the field instrument devices transmit the instrument data signals to a data transmission cabinet, the data transmission cabinet transmits the signals to a centralized control platform, the centralized control platform is calculated through a data operation module, the calculation result includes the average chloride ion content of the wastewater, and abnormal alarm and / or control are performed according to the calculation result and the instrument data. The circulating water discharge amount and the circulating water discharge water quality of all production units in the steel plant are controlled in real time, so that the production data of each production unit can be adjusted in time through the centralized control data, and the wastewater recovery index can be adjusted to, and the effect is achieved.

Description

A smart control system and control method for wastewater recycling in steel plants Technical Field

[0001] This invention relates to the field of wastewater recycling system technology, and in particular to an intelligent control system and control method for wastewater recycling in steel plants. Background Technology

[0002] Long-process steel enterprises typically involve multiple production steps, including coking, sintering, pelletizing, ironmaking, steelmaking, rolling, power generation, and other auxiliary facilities. When recycling production wastewater, the volume and quality of wastewater from each step often vary significantly. Therefore, a wastewater equalization tank is usually installed at the front end of centralized wastewater treatment, which presents the following problems:

[0003] 1. Centralized discharge from each unit leads to peak wastewater recovery and insufficient treatment capacity in centralized treatment.

[0004] 2. Due to the significant differences in the quality of the wastewater discharged from each unit, the water quality fluctuates greatly during centralized wastewater recycling and treatment. There may be instances where indicators such as conductivity, chloride ions, and total iron exceed the design specifications, increasing the load on the processes in the downstream water tank.

[0005] 3. In long-process steel enterprises, there are some special wastewaters in processes such as coking, sintering, and gas power generation. Under normal production conditions, these special wastewaters are treated within the unit. However, there are cases where special wastewaters flow into general wastewater collection tanks, which can damage membrane elements in subsequent wastewater treatment.

[0006] Currently, the main approach to controlling peak wastewater recovery is through management measures, such as limiting the discharge volume and time of each unit. This approach consumes a lot of manpower, has a long response time to abnormal situations, and has low processing capacity. Summary of the Invention

[0007] The purpose of this invention is to provide an intelligent control system for wastewater recycling in steel plants, which can monitor the amount and quality of circulating water discharged from all production units within the steel plant in real time, so that each production unit can adjust its production data in a timely manner through centralized control data. The wastewater quality is based on chloride ions and adjusted to the wastewater recycling index according to the water-salt balance.

[0008] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0009] A smart control system for wastewater recycling in a steel plant includes field instruments installed in various wastewater collection tanks. The field instruments test data including flow rate and chloride ion concentration. The field instruments transmit the instrument data signals to a data transmission cabinet, which then transmits the signals to a centralized control platform. The centralized control platform calculates the average chloride ion content of the wastewater using a data processing module. Based on the calculation results and instrument data, the platform performs abnormal alarms and / or controls.

[0010] Furthermore, the instrument data tested by the field instruments also includes pH value and conductivity. The centralized control platform compares the pH value and conductivity with preset values ​​and issues alarms and / or reminders based on the comparison results.

[0011] Furthermore, if the pH value deviation is ±0.5, or the conductivity or chloride ion concentration deviation exceeds +20%, the centralized control platform shuts off the power supply to the corresponding collection tank's water pump and issues an alarm, indicating abnormal water quality. If the conductivity or chloride ion concentration deviation exceeds -20%, the centralized control platform displays that the circulating water concentration ratio of this branch plant is low and reminds users to increase the concentration ratio.

[0012] Furthermore, the average chloride ion content of the wastewater is obtained based on the flow rate and chloride ion concentration of each wastewater collection tank, and the flow rate of each wastewater collection tank is adjusted according to the obtained average chloride ion content.

[0013] Furthermore, the flow rate of each wastewater collection tank is adjusted to ensure that the average chloride ion content of the wastewater is between 420 mg / L and 450 mg / L.

[0014] Furthermore, the calculation results of the data processing module also include the flow rate of each wastewater collection tank. If the flow rate exceeds the preset centralized wastewater treatment capacity, it is determined that there is a peak in wastewater recycling.

[0015] Furthermore, the instrument data tested by the field instrumentation devices also includes flow rate. When there is a peak in wastewater recovery, the centralized control platform controls and regulates the start and stop of the sewage pumps in each wastewater collection tank according to the liquid level of each wastewater collection tank.

[0016] This application also discloses a method for controlling wastewater recycling in steel plants, comprising the following steps.

[0017] First, calculate the total flow rate of each wastewater collection tank. If it is not greater than the preset centralized wastewater treatment capacity, it is determined to be in normal operation. If it is greater than the preset centralized wastewater treatment capacity, it is determined that there is a peak in wastewater recycling.

[0018] When the system is judged to be operating normally, the average chloride ion content of the current wastewater recovery is calculated, and then the flow rate of each wastewater collection tank is adjusted to adjust the average chloride ion content of the wastewater recovery, thereby achieving the optimal range designed.

[0019] When a peak in the recovery is detected, the start and stop of the sewage pumps in each wastewater collection tank are controlled according to the liquid level of each wastewater collection tank.

[0020] Furthermore, .

[0021] In summary, the present invention has the following beneficial effects:

[0022] Through online monitoring instruments, the amount and quality of circulating water discharge from all production units within the steel plant can be monitored in real time. Each production unit can adjust its production data in a timely manner through centralized control data. The wastewater quality is automatically adjusted to the wastewater recovery index based on chloride ions and in accordance with the water-salt balance formula.

[0023] The entire system includes a comprehensive interlocking and alarm mechanism, reducing the risk of special wastewater flowing into the general wastewater pipe network and providing a fast response time to water quality anomalies. Under normal production conditions, the system can be automatically controlled, greatly reducing on-site manpower consumption. The reliance on wastewater equalization tanks is reduced, allowing for a suitable reduction in the construction scale of equalization tanks and lower infrastructure investment. Attached Figure Description

[0024] Figure 1 is a schematic diagram of the structure of a steel plant wastewater recycling intelligent control system according to the present invention;

[0025] Figure 2 is a schematic flowchart of a wastewater recycling and control method for steel plants according to the present invention. Detailed Implementation Methods

[0026] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. These embodiments do not constitute a limitation of the present invention. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this application.

[0027] A smart control system for wastewater recycling in a steel plant, as shown in Figure 1, includes field instruments installed in various wastewater collection tanks. Wastewater collection tanks are built in various areas of the plant, typically with 1-3 wastewater collection tanks per area (45 wastewater collection tanks are set up in the whole plant, with 2-3 wastewater collection tanks in the main production units and 1 wastewater collection tank in the auxiliary units). Each wastewater collection tank is typically equipped with 3 submersible pumps, 2 in use and 1 as a backup. An electric valve is installed at the outlet main pipe, along with corresponding field instruments and data transmission cabinets.

[0028] The field instrumentation includes radar level gauges, ultrasonic flow meters, pH meters, conductivity meters, and online chloride ion monitors. The corresponding instrument data measured include level, flow rate, pH value, conductivity, and chloride ion concentration.

[0029] Each wastewater collection tank is equipped with a separate data transmission cabinet. Instrument data is displayed in the centralized control system via the signal transmission cabinet. Field instruments transmit instrument data signals to the data transmission cabinet, which mainly includes photoelectric converters, switching power supplies, and power distribution units. The data transmission cabinet then transmits the signals to the centralized control platform. The real-time data in the centralized control system is refreshed every 5 seconds.

[0030] The centralized control platform calculates the average chloride ion content of the wastewater through the data processing module, and performs abnormal alarms and / or adjustments based on the calculation results and instrument data.

[0031] As shown in Figure 1, the centralized control platform compares the pH value and conductivity with preset values ​​and issues alarms and / or reminders based on the comparison results. If the pH value deviation is ±0.5, or the conductivity or chloride ion concentration deviation exceeds +20%, the centralized control platform shuts off the power supply to the water pump in the corresponding collection tank and issues an alarm to indicate abnormal water quality. If the conductivity or chloride ion concentration deviation exceeds -20%, the centralized control platform displays that the concentration ratio of the circulating water in this branch plant is low and reminds users to increase the concentration ratio.

[0032] The system can also be configured to not alarm for wastewater with high chloride ion content, such as blast furnace slag flushing water. By setting system parameters in advance, the system can automatically adjust the current wastewater recovery volume and quality to the optimal state.

[0033] As shown in Figure 1, the average chloride ion content of the wastewater is obtained based on the flow rate and chloride ion concentration of each wastewater collection tank, and the flow rate of each wastewater collection tank is adjusted according to the obtained average chloride ion concentration; wherein, the flow rate of each wastewater collection tank is adjusted so that the average chloride ion content of the wastewater is between 420 mg / L and 450 mg / L.

[0034] The calculation results of the data processing module also include the flow rate of each wastewater collection tank. If the flow rate exceeds the preset centralized wastewater treatment capacity, it is determined that there is a peak in wastewater recovery. When there is a peak in wastewater recovery, the centralized control platform controls and regulates the start and stop of the sewage pumps in each wastewater collection tank according to the liquid level of each wastewater collection tank.

[0035] As shown in Figure 2, this application also discloses a method for controlling wastewater recycling in steel plants, including the following steps.

[0036] S1: First, make a preliminary judgment on the data, compare the pH value and conductivity with the preset values ​​(the pH value of wastewater is set to 7-9, the conductivity is set to 1950 and the chloride ion is set to 450mg / l), and issue an alarm and / or reminder based on the comparison results;

[0037] When real-time data is compared with preset indicators, if the pH value deviation is ±0.5 and / or the conductivity or chloride ion concentration deviation exceeds +20%, the centralized control platform will shut down the power supply of the water pump in the corresponding collection tank and issue an alarm to indicate abnormal water quality.

[0038] If the conductivity or chloride ion concentration deviation exceeds -20%, the centralized control platform will display that the concentration ratio of the circulating water in this branch plant is low, prompting a reminder to increase the concentration ratio.

[0039] S2: Through parameter settings and data calculations, the platform can automatically adjust the volume and quality of recycled wastewater. The plant's general wastewater treatment capacity is 1600 m³ / h, the peak discharge volume is approximately 2000 m³ / h, and the average wastewater recovery volume is 1400 m³ / h. Through automatic system adjustment, the overall wastewater recovery fluctuation is maintained between 1450-1600 m³ / h. During normal production, except for the uncontrollable peak discharge in summer, the system operates normally at other times.

[0040] The water quality of the entire plant is uniformly based on chloride ions, with the optimal water quality index of chloride ions set at 450 mg / L. The chloride ion concentration in the wastewater collection tank is between 350 mg / L and 550 mg / L, while the chloride ion concentration in the blast furnace slag flushing water is between 2000 mg / L and 3000 mg / L. Through intelligent system adjustment, the overall water quality is stabilized at 420 mg / L to 450 mg / L.

[0041] By implementing the intelligent wastewater recycling control system, we can avoid peak wastewater recycling levels, ensure the overall stability of wastewater quality, and significantly reduce the risk of special wastewater from steel companies flowing into general wastewater collection ponds through a robust alarm mechanism.

[0042] Specifically, first calculate the flow rate of each wastewater collection tank. If it is not greater than the preset centralized wastewater treatment capacity, it is determined to be in normal operation. If it is greater than the preset centralized wastewater treatment capacity, it is determined that there is a peak in wastewater recycling.

[0043] When the system is determined to be operating normally, the average chloride ion content of the recovered wastewater is calculated. Then, the flow rate of each wastewater collection tank is adjusted to regulate the average chloride ion content of the recovered wastewater, thereby achieving the optimal design range.

[0044]

[0045] When a peak in wastewater recovery is detected, the system uses radar level gauges to obtain the water levels in each wastewater collection tank and controls the start and stop of the sewage pumps in each tank. If the peak wastewater recovery value is too high and the automatic flow adjustment cannot meet the requirements, an early warning will be issued, and relevant personnel will manually intervene upon receiving the warning.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within the scope of its essence and protection. Such modifications or equivalent substitutions should also be considered to fall within the protection scope of the present invention.

Claims

1. A smart control system for wastewater recycling in steel plants, characterized in that: This includes field instruments installed in each wastewater collection tank. These field instruments measure data including flow rate and chloride ion concentration. The field instruments transmit this data to a data transmission cabinet, which then transmits it to a centralized control platform. The platform uses a data processing module to calculate the average chloride ion content of the wastewater. Based on the calculation results and instrument data, the platform performs alarms and / or controls for any anomalies. The average chloride ion content is determined by the flow rate and chloride ion concentration of each wastewater collection tank, and the flow rate of each tank is adjusted accordingly based on this average chloride ion content. The wastewater recovery control method includes the following steps: First, calculate the flow rate of each wastewater collection tank. If it is not greater than the preset centralized wastewater treatment capacity, it is determined to be in normal operation. If it is greater than the preset centralized wastewater treatment capacity, it is determined that there is a peak in wastewater recovery. When it is determined to be in normal operation, calculate the average chloride ion content of the current wastewater recovery, and then adjust the flow rate of each wastewater collection tank to adjust the average chloride ion content of the wastewater recovery, thereby achieving the optimal range designed. When it is determined that there is a peak in recovery, control the start and stop of the sewage pumps in each wastewater collection tank according to the liquid level of each wastewater collection tank.

2. The intelligent control system for wastewater recycling in a steel plant according to claim 1, characterized in that: The instrument data tested by the field instruments also include pH value and conductivity. The centralized control platform compares the pH value and conductivity with preset values ​​and issues alarms and / or reminders based on the comparison results.

3. The intelligent control system for wastewater recycling in a steel plant according to claim 2, characterized in that: If the pH value deviation is ±0.5, or the conductivity or chloride ion concentration deviation exceeds +20%, the centralized control platform will shut down the power supply to the corresponding collection tank's water pump and issue an alarm, indicating abnormal water quality. If the conductivity or chloride ion concentration deviation exceeds -20%, the centralized control platform will display that the circulating water concentration ratio of this branch plant is low and remind users to increase the concentration ratio.

4. The intelligent control system for wastewater recycling in a steel plant according to claim 1, characterized in that: The flow rate of each wastewater collection tank is adjusted to ensure that the average chloride ion content of the wastewater is between 420 mg / L and 450 mg / L.

5. The intelligent control system for wastewater recycling in a steel plant according to claim 1, characterized in that: The calculation results of the data processing module also include the flow rate of each wastewater collection tank. If the flow rate exceeds the preset centralized wastewater treatment capacity, it is determined that there is a peak in wastewater recycling.

6. The intelligent control system for wastewater recycling in a steel plant according to claim 1, characterized in that: 。

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