CN107473477A - A kind of desalted water production process unattended intelligent control system - Google Patents

Abstract

An unattended intelligent control system for the desalinated water production process, which relates to a desalinated water production system. The program control program of the desalted water ultrafiltration, reverse osmosis and mixed bed devices designed by the present invention realizes the automatic control of each device. The designed Statistical process control realizes the statistical calculation of each valve feedback time, flow change rate, flow change range, pump utilization rate and each device utilization rate. It can realize the prediction of the health status of valves and devices, balance the utilization rate of pumps and devices, design ultrafiltration, The reverse osmosis and mixed bed water tank liquid level control point realizes the automatic start-up control of each device, the designed alarm system notifies the operator to carry out maintenance, and finally realizes the unattended control of the desalinated water production process through the above method.

Description

An unattended intelligent control system for desalinated water production process

technical field

The invention relates to a desalinated water production system, in particular to an unattended intelligent control system for the desalinated water production process.

Background technique

In the process of industrial production, desalinated water is generally used for process production water, the purpose is to remove various anions and cations in the water, and avoid problems such as emulsification and scaling in the subsequent use process. The desalinated water production process generally includes three devices: ultrafiltration, reverse osmosis and mixed bed. The brief process is: the industrial raw water from outside the boundary directly enters the raw water tank, and after being pressurized by the raw water pump, it enters the steam heat exchanger and then enters After the laminated filter removes large particles of impurities in the water, it directly enters the ultrafiltration device to reduce the pollution index. The effluent enters the ultrafiltration water tank, is pressurized by the ultrafiltration water pump, and then sent to the security filter, and then enters the reverse osmosis device through a high pressure pump. The fresh water that removes more than 97% of the salt in the water directly enters the intermediate water tank, and after being pressurized by the intermediate water pump, enters the mixed bed to remove the remaining anions and cations in the water, and then obtains qualified desalted water, enters the desalted water tank, and finally boosts the pressure by the desalted water pump sent to the user. Since desalinated water is the main water used in other process sections, if desalinated water is not well controlled, it will seriously affect the production of other processes and cause economic losses. For desalinated water production control, the current main method is that the operator chooses to close or open the desalted water device according to the process conditions, which will cause the following problems: ① The operator must monitor the desalinated water production process at all times; ② Switching and using the device Due to human factors, the utilization rate of the device will be uneven; ③The operator cannot evaluate the health status of the device, and only when there is a problem with the device will it be repaired. In short, the traditional manual control is too simple to realize the intelligent production of the desalted water production process.

Contents of the invention

The purpose of the present invention is to provide an unattended intelligent control system for the desalinated water production process. The purpose of the invention is to design an unattended intelligent control method for the desalinated water production process to solve the above problems, thereby reducing manual operations and balancing The device utilization rate predicts the health status of the device and equipment to ensure the smooth and healthy operation of the desalinated water production process.

The purpose of the present invention is achieved through the following technical solutions:

An unattended intelligent control system for the desalinated water production process, the system includes a solenoid valve, a water flow transmitter, a water tank, a water pump, a heat exchanger, a steam regulating valve, and an ultrafiltration device; the ultrafiltration device includes three sets of devices , the control procedures of the three sets of devices are the same, and the process working status of the ultrafiltration device is divided into three states: operation, normal backwash and chemically enhanced backwash;

Including the following process:

(1) When ultrafiltration is running, only one step of filtration is performed;

(2) During normal backwashing, it is necessary to perform backwashing lower row, backwashing quick flushing upper row and quick flushing upper row;

(3) When chemically enhanced backwashing, it is necessary to perform drug feeding, soaking, rinsing and normal backwashing;

The reverse osmosis device is divided into the start state and the stop state; the process automatic control procedure is as follows:

(1) When starting up, it is necessary to perform low-pressure flushing and water production;

(2) When shutting down, it is necessary to perform shutdown high-pressure flushing and shutdown low-pressure flushing;

The whole process of the mixed bed device is divided into three process states of flushing, water production and regeneration; the process automatic control procedure is as follows:

(1) When flushing, open the water inlet valve, the washing drain valve, the instrument connection valve, the unqualified return valve and the intermediate water pump;

(2) When making water, open the water inlet valve, water outlet valve, instrument connection valve and intermediate water pump;

(3) When regenerating, it is necessary to perform water release, invalidation, backwash stratification, settlement, water release, metering check, regenerant injection, injection check, replacement, water release, air mixing, water filling, normal washing and standby;

When the liquid level of the logically interlocked raw water tank is high, the production water valve is closed, and when the liquid level is low, the production water valve is opened, the raw water pump and the ultrafiltration device are closed; when the liquid level of the ultrafiltration water tank is low, the ultrafiltration water pump and the reverse osmosis device are closed; When the liquid level of the infiltration water tank is low, turn off the intermediate water pump and the mixed bed device; when the liquid level of the desalted water tank is low, turn off the desalted water pump;

The ultrafiltration device is self-starting and self-stopping, and the ultrafiltration water tank is set with a position mark;

The reverse osmosis device is self-starting and self-stopping, and the position mark of the reverse osmosis water tank is set;

The mixed bed device is self-starting and self-stopping, and the position mark is set for the mixed bed water tank;

Statistical process control, collecting the feedback time of all switch valves, valve failure, flow change rate, flow change range, instrument failure, pump failure, single pump usage rate and water tank level of each device;

The alarm system is as follows:

(1) Man-machine interface alarm;

(2) Sound and light alarm;

(3) SMS alarm.

In the unattended intelligent control system for the desalinated water production process, the ultrafiltration device turns on the backwash water pump when chemically enhanced backwash feeds the medicine, adds the bactericide metering pump, the medicine feed pump, the backwash water inlet valve and the backwash water inlet valve. Wash the upper drain valve; close all pumps and valves when soaking; turn on the backwash pump, backwash water inlet valve and backwash upper drain valve during rinsing, and perform normal backwash steps during normal backwashing.

In the unattended intelligent control system for the desalinated water production process, when the reverse osmosis device is turned on, the water inlet valve is opened during low-pressure flushing, the produced water quick discharge valve, the concentrated water quick discharge valve, the ultrafiltration water pump and the reducing agent are added Metering pump; open the water inlet valve when making water, ultrafiltration water pump, high pressure pump, adding reducing agent metering pump and adding antiscalant metering pump; when shutting down, open the water inlet valve during high pressure flushing, open the produced water quick discharge valve, and concentrate water quickly Exhaust valve, ultrafiltration water pump, high-pressure pump, reducing agent metering pump and antiscalant metering pump; open the product water quick discharge valve, concentrated water quick discharge valve, flushing water inlet valve and low pressure flushing pump when shutting down for low pressure flushing.

In the unattended intelligent control system of the desalinated water production process, the upper drain valve and exhaust valve are opened when the mixed bed device discharges water; the alkali inlet valve, alkali outlet valve, water inlet valve and regeneration water pump are opened when it fails; Open the backwash inlet valve, backwash drain valve and intermediate water pump when backwashing is stratified; close all valves and pumps when settling; open the upper drain valve and exhaust valve when releasing water; open the acid inlet valve and alkali inlet valve when measuring and checking valve; open the acid inlet valve, alkali inlet valve, regeneration discharge valve, acid outlet valve, water inlet valve, alkali outlet valve, water inlet valve and regeneration water pump when regenerant is fed; close all valves and pumps when injecting and checking; replace Open the acid inlet valve, alkali inlet valve, regeneration drain valve, water inlet valve, water inlet valve and regeneration pump; when discharging water, open the upper drain valve and exhaust valve; when air is mixed, open the backwash drain valve, inlet valve and Exhaust valve; open the inlet valve, exhaust valve and intermediate water pump when filling water; open the inlet valve and drain valve during normal washing; instrument connection valve, unqualified return valve and intermediate water pump; close all valves and intermediate water pumps when not in use Pump.

In the unattended intelligent control system for the desalinated water production process, the operator screen alarm of the man-machine interface of the alarm system is divided into alarm history information and flow chart screen alarm, and the historical information provides detailed alarm records. The graph screen alarm gives an intuitive and accurate alarm location.

In the unattended intelligent control system for the desalinated water production process, the alarm system has sound and light alarm. When an alarm occurs, the DCS or PLC controller sends the alarm signal to the sound and light alarm through the I/O card through the wire. The device uses different alarm sounds to indicate different alarm levels, and prompts the operator.

In the unattended intelligent control system for the desalinated water production process, the alarm system's SMS alarm, equipment failure and other alarm information are sent to maintenance personnel through the alarm SMS platform.

Advantage and effect of the present invention are:

The unattended intelligent production of the desalted water production process can be realized through the automatic control program. At the same time, the statistical process control is adopted to realize the balanced use of each device and predict the health status of the equipment, so as to extend the service life of the device and carry out equipment inspection in advance.

Description of drawings

Figure 1 Structural diagram of desalinated water control system;

Figure 2 Schematic diagram of the process flow of the desalted water preheating device;

Figure 3 Schematic diagram of the process flow of the desalted water ultrafiltration device;

Figure 4 Schematic diagram of the process flow of the desalted water reverse osmosis unit;

Figure 5 Schematic diagram of the process flow of the desalted water mixed bed device;

Fig. 6 Flow chart of the unattended program in the desalinated water production process;

Fig. 7 is the program flow chart of the ultrafiltration device;

Figure 8 is the program flow chart of the reverse osmosis device;

Figure 9 is the flow chart of the mixed-bed program installation.

detailed description

The present invention will be described in detail below in conjunction with examples.

The present invention provides following technical scheme:

1. Program-controlled design of the device

(1) Program-controlled design of ultrafiltration device

The main function of the ultrafiltration process is to reduce the pollutants in the raw water and reduce the pollution index to below 3. The entire process working state of the ultrafiltration device is divided into three states: operation, normal backwash and chemically enhanced backwash. The automatic control program design of each process work is as follows:

① When ultrafiltration is running, only one step of filtration is performed. This step needs to start the raw water pump, water inlet valve, and water production valve.

②During normal backwashing, it is necessary to perform three steps of backwashing lower row, backwashing quick flushing upper row and quick flushing upper row, and a timer is used to time the switching between steps. The specific process is as follows:

Step 1: Turn on the raw water pump for backwashing, add bactericide metering pump, backwash water inlet valve and backwash lower discharge valve;

Step 2: Turn on the raw water pump, backwash water pump, water inlet valve, backwash water inlet valve and backwash upper discharge valve when backwashing is fast flushing and upper row;

Step 3: Turn on the raw water pump, the water inlet valve and the backwash upper discharge valve when flushing the upper row quickly.

③ When chemically enhanced backwashing, it is necessary to perform three steps of feeding, soaking, rinsing and normal backwashing. The specific process is as follows:

Step 1: Turn on the backwash water pump when feeding the medicine, add the fungicide metering pump, the medicine feed pump, the backwash water inlet valve and the backwash upper discharge valve;

Step 2: Close all pumps and valves during soaking;

Step 3: Turn on the backwash pump during rinsing, backwash the water inlet valve and the backwash upper discharge valve, and perform the normal backwashing steps during normal backwashing.

(2) Program-controlled design of reverse osmosis device

The main function of the reverse osmosis process is to remove more than 97% of the salt in the raw water. The whole process of the device is divided into two working states: the start state and the stop state. The automatic control program design of each process work is as follows:

① When starting up, two steps of low-pressure flushing and water production need to be performed.

Step 1: Open the water inlet valve, the produced water quick discharge valve, the concentrated water quick discharge valve, the ultrafiltration water pump and the reducing agent metering pump when starting up the low pressure flushing;

Step 2: When making water, open the water inlet valve, ultrafiltration water pump, high pressure pump, adding reducing agent metering pump and adding antiscalant metering pump.

② When shutting down, it is necessary to perform shutdown high-pressure flushing and shutdown low-pressure flushing.

Step 1: Shut down the water inlet valve during high-pressure flushing, open the product water quick discharge valve, concentrated water quick discharge valve, ultrafiltration water pump, high pressure pump, adding reducing agent metering pump and adding scale inhibitor metering pump;

Step 2: Open the product water quick discharge valve, the concentrated water quick discharge valve, the flushing water inlet valve and the low pressure flushing pump when the machine is shut down for low pressure flushing.

(3) Program-controlled design of mixed bed unit

The main function of the mixed bed process is to remove the remaining anions and cations in the raw water and produce qualified desalinated water. The whole process is divided into three process states of flushing, water production and regeneration. The automatic control program design of each process work is as follows:

① When flushing, only one step is performed, which is to open the water inlet valve, the positive washing drain valve, the instrument connection valve, the unqualified return valve and the intermediate water pump.

②When making water, only one step is performed, which is to open the water inlet valve, water outlet valve, instrument connection valve and intermediate water pump.

③ When regenerating, it is necessary to perform fourteen steps: water release, invalidation, backwash stratification, settlement, water release, metering check, regenerant injection, injection check, replacement, water release, air mixing, water filling, normal washing and standby.

Step 1: Open the upper drain valve and exhaust valve when releasing water;

Step 2: Open the alkali inlet valve, alkali outlet valve, water inlet valve and regeneration water pump when failure occurs;

Step 3: Open the backwash inlet valve, backwash drain valve and intermediate water pump when backwashing is stratified;

Step 4: Close all valves and pumps when settling;

Step 5: Open the upper drain valve and exhaust valve when releasing water;

Step 6: Open the acid inlet valve and alkali inlet valve during metering calibration;

Step 7: Open the acid inlet valve, alkali inlet valve, regeneration discharge valve, acid outlet valve, water inlet valve, alkali outlet valve, water inlet valve and regeneration water pump when regenerant is being fed;

Step 8: Close all valves and pumps during injection calibration;

Step 9: Open the acid inlet valve, alkali inlet valve, regeneration drain valve, water inlet valve, water inlet valve and regeneration pump during replacement;

Step 10: Open the upper drain valve and exhaust valve when draining water;

Step 11: When the air is mixed, open the backwash drain valve, intake valve and exhaust valve;

Step 12: Open the water inlet valve, exhaust valve and intermediate water pump when filling water; open the water inlet valve when washing, and wash the drain valve;

Step 13: When washing, the instrument takes over the valve, the unqualified return valve and the intermediate water pump;

Step Fourteen: Close all valves and pumps when not in use.

2. Logic interlocking design

Close the production water valve when the liquid level of the raw water tank is high, open the production water valve and close the raw water pump when the liquid level is low; close the ultrafiltration water pump when the liquid level of the ultrafiltration water tank is low; turn off the intermediate water pump when the liquid level of the reverse osmosis water tank is low ; Turn off the desalted water pump when the liquid level in the desalted water tank is low.

3. Design of automatic start-stop device

Automatic start-stop design for three sets of ultrafiltration device, reverse osmosis device and mixed bed device. The three sets of devices correspond to three sets of ultrafiltration water tanks, reverse osmosis water tanks and desalinated water tanks respectively. Four position marks are set for the liquid level of each water tank, namely sp0, sp1, sp2 and sp3, and satisfy sp0>sp1>sp2>sp3. When the liquid level of any water tank is less than sp1 and greater than sp2, start the first set of corresponding devices; when the liquid level is less than sp2 and greater than sp3, start the second set of corresponding devices; when the liquid level is less than sp3, start the third set of corresponding devices; otherwise When the liquid level is greater than sp2, close one set of corresponding devices; when the liquid level is greater than sp1, close another set of corresponding devices; when the liquid level is greater than sp0, close the last set of corresponding devices.

4. Pump and device standby automatic switching design

When the pump and device have a backup, when any of them fails, it can be automatically switched to the backup through logical judgment to ensure uninterrupted production.

5. Statistical Process Control Design

Calculate the sum

Calculate mean

Calculate standard deviation

Make statistics on the feedback time of each valve switch and calculate its average value and standard deviation , for the calculated , Automatic comparison with the data of the health status can predict the health status of valves and equipment. If the predicted health status is abnormal, an alarm will be issued to prompt maintenance. Statistics on the usage rate of pumps, valves and devices, and calculate the total number of usage , to automatically balance their usage, preventing a single device from being used too much while another is used too little.

6. Alarm design

① Man-machine interface alarm. Divided into alarm history information and flowchart screen alarm, historical information provides detailed alarm records, and flowchart screen alarm provides intuitive and accurate alarm location.

②Sound and light alarm. By designing different alarm sounds to indicate different alarm levels, prompting the operator.

③SMS alarm. Alarm information such as equipment failure can be sent to maintenance personnel through the alarm SMS platform.

The equipment used in the control system includes ultra-filtration production water solenoid valve XV01, production water flow transmitter FI01, raw water tank T1, raw water pump P01A/B/C, raw water flow transmitter FI02, heat exchanger E1, steam regulating valve TV01 , Outlet heat exchanger raw water temperature transmitter TIC01, filter device A/B/C, ultrafiltration water flow transmitter FI03A/B/C, ultrafiltration water tank T2, ultrafiltration water tank liquid level transmitter LI02, ultrafiltration Water pump P02A/B/C, reverse osmosis device A/B/C, reverse osmosis water flow transmitter FI04A/B/C, reverse osmosis water tank T3, reverse osmosis water tank liquid level transmitter LI03, intermediate water pump P03A/B/ C. Mixed bed device A/B/C, mixed bed water flow transmitter FI05A/B/C, desalted water tank T4, desalted water tank liquid level transmitter LI04, desalted water pump P04A/B, desalted water flow transmitter FI06 Among them, the ultrafiltration device A/B/C also includes valve inlet solenoid valve V1ACL, water production solenoid valve V2ACL, backwash inlet solenoid valve V3ACL, backwash upper row solenoid valve V4ACL, backwash lower row solenoid valve V5ACL, plus Bactericide metering pump P1A/BCMCL, backwash water pump P2A/BCMCL, drug feed pump P3A/BCMCL, reverse osmosis unit A/B/C also includes water inlet solenoid valve V1AFS, produced water fast discharge solenoid valve V2AFS, concentrated water fast discharge Solenoid valve V3AFS, flushing water inlet solenoid valve V4AFS, high-pressure pump P1AFS, antiscalant metering pump P2AFS, reducing agent metering pump P1A/BCMFS, low-pressure flushing pump P2A/BCMFS, mixed bed device A/B/C also included Water solenoid valve V1AHC, water outlet solenoid valve V2AHC, backwash water inlet solenoid valve V3AHC, backwash drain solenoid valve V4AHC, forward wash drain solenoid valve V5AHC, water inlet solenoid valve V6CMHC, acid inlet solenoid valve V7AHC, alkali inlet solenoid valve V8AHC, Regenerative liquid discharge solenoid valve V9AHC, intake solenoid valve V10AHC, exhaust solenoid valve V11AHC, instrument takeover solenoid valve V12AHC, unqualified return water solenoid valve V13AHC, acid inlet solenoid valve V1CMHC, acid outlet solenoid valve V2CMHC, water inlet solenoid valve V3CMHC , Alkali inlet solenoid valve V4CMHC, alkali outlet solenoid valve V5CMHC, water inlet solenoid valve V6CMHC, regeneration water pump P1A/BCMHC. The production water passes through the solenoid valve XV01, the flow rate is detected by FI01, and enters T1, the liquid level is detected by LI01, pumped into it by pump P01A/B/C, the flow rate of the heat exchanger E1 is detected by FI02, and the raw water temperature of the heat exchanger is adjusted by Controlled by valve TV01, it enters the ultrafiltration device A/B/C, and the ultrafiltered water is sent to T2, the flow rate is detected by FI03A/B/C, the liquid level is detected by LI02, and then pumped into the water by pump P02A/B/C Reverse osmosis device A/B/C, the water after reverse osmosis is sent to T3, the flow rate is detected by FI04A/B/C, the liquid level is detected by LI03, and then pumped into the mixed bed A/B/B by pump P03A/B/C C. After the mixed bed, qualified desalted water is produced and sent to T4. The flow rate is detected by FI05A/B/C, the liquid level is detected by LI04, and finally pumped out by pump P04A/B according to the user's demand, and the flow rate is detected by FI06. .

On the DCS or PLC platform S001, unattended intelligent control system S002 is designed, and the I/O card S003 is connected with the on-site regulating valve S004, solenoid valve S005, solenoid valve status S006, pump S007, pump status S008, flow rate Transmitter S009, liquid level transmitter S010, temperature transmitter S011 and sound and light alarm S012, equipment alarms are sent to maintenance personnel through the SMS alarm platform S013.

Example:

1. Program-controlled design of ultrafiltration device

Ultrafiltration consists of three sets of devices, and the control procedures of the three sets of devices are the same. Here, one set is used as an example to illustrate. The entire process working state of the ultrafiltration device is divided into three states: running CL001, normal backwashing CL003 and chemically enhanced backwashing CL007. The automatic control program design of each process work is as follows:

(1) When ultrafiltration is running, only one step of filtration is performed. This step needs to start the raw water pump P01A/B/C, the water inlet valve V1ACL, and the water production valve V2ACL.

(2) When backwashing CL003 normally, it is necessary to perform backwash lower row CL004, backwash fast flush upper row CL005 and quick flush upper row CL006. Turn on the raw water pump P01A/B/C when backwashing the lower row CL004, add fungicide metering pump P1A/BCMCL, backwash the inlet valve V3ACL and backwash the lower discharge valve V5ACL; turn on the raw water pump P01A when backwashing the upper row CL005 /B/C, backwash water pump P2A/BCMCL, water inlet valve V1ACL, backwash water inlet valve V3ACL and backwash upper discharge valve V4ACL; open raw water pump P01A/B/C, water inlet valve V1ACL when fast flushing upper row CL006 And backwash the upper drain valve V4ACL.

(3) When chemically enhanced backwashing CL007, it is necessary to perform drug feeding CL008, soaking CL009, rinsing CL010 and normal backwashing CL003. When feeding CL008, turn on the backwash pump P2A/BCMCL, add the fungicide metering pump P1A/BCMCL, feed the drug pump P3A/BCMCL, backwash the water inlet valve V3ACL and backwash the upper discharge valve V4ACL; when soaking CL009, all pumps and Valve; when rinsing CL010, turn on backwash pump P2A/BCMCL, backwash inlet valve V3ACL and backwash upper drain valve V4ACL, and perform normal backwash CL003 steps when backwashing CL003 normally.

2. Program-controlled design of reverse osmosis device

The entire process working state of the reverse osmosis device is divided into the starting state FS001 and the stopping state FS001. The automatic control program design of each process work is as follows:

(1) When starting FS001, it is necessary to perform low-pressure flushing FS002 and water production FS003. Open water inlet valve V1AFS, water production quick discharge valve V2AFS, concentrated water quick discharge valve V3AFS, ultrafiltration water pump P1A/B/C and reducing agent metering pump P1A/BCMFS when starting low-pressure flushing FS002; open water inlet when water production FS003 Valve V1AFS, ultrafiltration water pump P1A/B/C, high pressure pump P1AFS, reducing agent metering pump P1A/BCMFS and scale inhibitor metering pump P2AFS.

(2) When shutting down FS004, it is necessary to perform shutdown high-pressure flushing FS005 and shutdown low-pressure flushing FS006. When shutting down and flushing FS005 with high pressure, the water inlet valve V1AFS, open the produced water quick discharge valve V2AFS, concentrated water quick discharge valve V3AFS, ultrafiltration water pump P1A/B/C, high pressure pump P1AFS, add reducing agent metering pump P1A/BCMFS and add scale inhibitor Agent metering pump P2AFS; when the low-pressure flushing FS006 is shut down, open the product water quick discharge valve V2AFS, the concentrated water quick discharge valve V3AFS, the flushing water inlet valve V4AFS and the low-pressure flushing pump P2A/BCMFS.

3. Program-controlled design of mixed bed unit

The entire process of the mixed bed device is divided into three process states: flushing HC001, water production HC002 and regeneration HC003. The automatic control program design of each process work is as follows:

(1) When flushing HC001, open the water inlet valve V1AHC, the positive washing drain valve V5AHC, the instrument connection valve V12AHC, the unqualified return valve V13AHC and the intermediate water pump P03A/B/C

(2) When making water HC002, open the water inlet valve V1AHC, the water outlet valve V2AHC, the instrument connection valve V12AHC and the intermediate water pump P03A/B/C.

(3) When regenerating HC003, it is necessary to perform water release HC004, invalidation HC005, backwash stratification HC006, sedimentation HC007, water release HC008, metering check HC009, regenerant HC010, injection check HC011, replacement HC012, water release HC013, air mixing HC014, irrigation HC015, washing HC016 and standby HC017. Open the upper drain valve V6AHC and exhaust valve V11AHC when discharging HC004; open the alkali inlet valve V8AHC, alkali outlet valve V5CMHC, water inlet valve V6CMHC and regeneration water pump P1A/BCMHC when HC005 fails; open the backwash inlet when backwashing stratification HC006 Valve V3AHC, backwash drain valve V4AHC and intermediate water pump P03A/B/C; close all valves and pumps when sinking HC007; open upper drain valve V6AHC and exhaust valve V11AHC when draining HC008; open acid inlet valve V1CMHC when metering and checking HC009 And alkali inlet valve V4CMHC; open acid inlet valve V7AHC, alkali inlet valve V8AHC, regeneration discharge valve V9AHC, acid outlet valve V2CMHC, water inlet valve V3CMHC, alkali outlet valve V5CMHC, water inlet valve V6CMHC and regeneration water pump P1A when regenerant HC010 is in /BCMHC; close all valves and pumps when injecting and checking HC011; open acid inlet valve V7AHC, alkali inlet valve V8AHC, regeneration drain valve V9AHC, water inlet valve V3CMHC, water inlet valve V6CMHC and regeneration pump P1A/BCMHC when replacing HC012; Open the upper drain valve V6AHC and exhaust valve V11AHC when discharging water HC013; open the backwash drain valve V4AHC, intake valve V10AHC and exhaust valve V11AHC when the air is mixed with HC014; open the intake valve V1AHC, exhaust valve V11AHC and Intermediate water pump P03A/B/C; when HC016 is being washed, open the water inlet valve, and when washing HC016, open the drain valve; instrument connection valve, unqualified return valve and intermediate water pump P03A/B/C; close all valves and pumps when HC017 is not in use.

4. Logic interlocking design

When the liquid level LI01 of the raw water tank T1 is high, close the production water valve XV01, and when the liquid level LI01 is low, open the production water valve XV01, close the raw water pump P01A/B/C and close the ultrafiltration device; the ultrafiltration water tank T2 liquid level LI02 is low Turn off the ultrafiltration water pump P02A/B/C and the reverse osmosis device; turn off the intermediate water pump P03A/B/C and the mixed bed device when the liquid level LI03 of the reverse osmosis water tank T3 is low; turn off the desalted water pump when the liquid level LI04 of the desalted water tank T4 is low P04A/B.

5. Self-start and self-stop design of ultrafiltration device

The ultrafiltration water tank T2 is set with four position marks, namely sp0, sp1, sp2 and sp3. When LI02 is at sp1, it will give a signal to open a set of ultrafiltration devices. When LI02 is at position sp2, it will give a signal to open a set of ultrafiltration devices. Signal, when LI02 is in sp3, it gives a signal to open a set of ultrafiltration device. When the liquid level LI02 returns to sp2, a signal to close a set of ultrafiltration devices is given. When the liquid level LI02 returns to sp1, a signal to close a set of ultrafiltration devices is given. When the liquid level LI02 returns to sp0, a signal to close a set of ultrafiltration devices is given. A set of ultrafiltration unit signals.

6. Self-start and self-stop design of reverse osmosis device

The reverse osmosis water tank T3 is set with four position marks, namely sp0, sp1, sp2 and sp3. When LI03 is at sp1, it will give a signal to open a set of reverse osmosis equipment. When LI03 is at position sp2, it will give a signal to open a set of reverse osmosis equipment. Signal, when LI03 is in position sp3, it gives a signal to open a reverse osmosis device. When the liquid level LI03 returns to sp2, a signal to close a set of reverse osmosis devices is given, when the liquid level LI03 returns to sp1, a signal to close a set of reverse osmosis devices is given, and when the liquid level LI03 returns to sp0, a signal to close a set of reverse osmosis devices is given A reverse osmosis unit signal.

7. Self-start and self-stop design of mixed bed unit

The mixed bed water tank T4 is set with four position marks, namely sp0, sp1, sp2 and sp3. When LI04 is at sp1, it will give a signal to start a mixed bed device. When LI04 is at position sp2, it will give a signal to start a mixed bed device. Signal, when LI04 is in position sp3, it gives a signal to start a set of mixed bed device. When the liquid level LI04 returns to sp2, a signal to close a set of mixed bed devices is given, when the liquid level LI04 returns to sp1, a signal to close a set of mixed bed devices is given, and when the liquid level LI04 returns to sp0, a signal to close a set of mixed bed devices is given A set of mixed bed unit signals.

8. Statistical Process Control Design

Collect the feedback time S014, valve fault S015, flow change rate S016, flow change range S017, instrument fault S018, pump fault S019, single pump utilization rate S020 and water tank liquid level S021 of all devices. Summarize the collected data ,average value and standard deviation Calculation, valve feedback statistics S023, flow signal statistics S024, pump usage statistics S025, device usage statistics S026 and water tank liquid level statistics S027, equipment and device health status prediction S028, equalization calculation S029 based on statistical results, The results of health status prediction S028 are sent to the alarm module S030. The alarm system S030 is designed with screen alarm S031, sound and light alarm S032 and SMS alarm S033. The equipment and device equalization calculation results S029 are sent to the automatic start-stop switching module S034 to start and stop the pump. Switch S035 or device program control S036 to start.

9. Alarm design

(1) Man-machine interface alarm. The operator screen alarm is divided into alarm history information and flowchart screen alarm. The historical information provides detailed alarm records, and the flowchart screen alarm provides intuitive and accurate alarm locations.

(2) Sound and light alarm. When an alarm occurs, the DCS or PLC controller S001 sends the alarm signal to the sound and light alarm device S012 through the I/O card S003 through the wire, and different alarm sounds are designed to indicate different alarm levels and prompt the operator.

(3) SMS alarm. Alarm information such as equipment failure can be sent to maintenance personnel through the alarm SMS platform.

Claims (7)

1. An unattended intelligent control system for a desalinated water production process, characterized in that the system includes a solenoid valve, a water flow transmitter, a water tank, a water pump, a heat exchanger, a steam regulating valve, and an ultrafiltration device; The filtration device includes three sets of devices, and the control procedures of the three sets of devices are the same. The process working status of the ultrafiltration device is divided into three states: operation, normal backwash and chemically enhanced backwash; Including the following process: (1) When ultrafiltration is running, only one step of filtration is performed; (2) During normal backwashing, it is necessary to perform backwashing lower row, backwashing quick flushing upper row and quick flushing upper row; (3) When chemically enhanced backwashing, it is necessary to perform drug feeding, soaking, rinsing and normal backwashing; The reverse osmosis device is divided into the start state and the stop state; the process automatic control procedure is as follows: (1) When starting up, it is necessary to perform low-pressure flushing and water production; (2) When shutting down, it is necessary to perform shutdown high-pressure flushing and shutdown low-pressure flushing; The whole process of the mixed bed device is divided into three process states of flushing, water production and regeneration; the process automatic control procedure is as follows: (1) When flushing, open the water inlet valve, the washing drain valve, the instrument connection valve, the unqualified return valve and the intermediate water pump; (2) When making water, open the water inlet valve, water outlet valve, instrument connection valve and intermediate water pump; (3) When regenerating, it is necessary to perform water release, invalidation, backwash stratification, settlement, water release, metering check, regenerant injection, injection check, replacement, water release, air mixing, water filling, normal washing and standby; When the liquid level of the logically interlocked raw water tank is high, the production water valve is closed, and when the liquid level is low, the production water valve is opened, the raw water pump and the ultrafiltration device are closed; when the liquid level of the ultrafiltration water tank is low, the ultrafiltration water pump and the reverse osmosis device are closed; When the liquid level of the infiltration water tank is low, turn off the intermediate water pump and the mixed bed device; when the liquid level of the desalted water tank is low, turn off the desalted water pump; The ultrafiltration device is self-starting and self-stopping, and the ultrafiltration water tank is set with a position mark; The reverse osmosis device is self-starting and self-stopping, and the position mark of the reverse osmosis water tank is set; The mixed bed device is self-starting and self-stopping, and the position mark is set for the mixed bed water tank; Statistical process control, collecting the feedback time of all switch valves, valve failure, flow change rate, flow change range, instrument failure, pump failure, single pump usage rate and water tank level of each device; The alarm system is as follows: (1) Man-machine interface alarm; (2) Sound and light alarm; (3) SMS alarm. 2. The unattended intelligent control system for a desalinated water production process according to claim 1, wherein the backwashing pump is turned on when the chemically enhanced backwashing of the ultrafiltration device is fed in, and the bactericide metering pump is added to enter Medicine pump, backwash water inlet valve and backwash upper discharge valve; all pumps and valves need to be closed for soaking; backwash water pump, backwash water inlet valve and backwash upper discharge valve are turned on during rinsing, and normal backwash is performed during normal backwash wash step. 3. The unattended intelligent control system for desalinated water production process according to claim 1, characterized in that, when the reverse osmosis device is turned on, the water inlet valve is opened when the reverse osmosis device is turned on for low-pressure flushing, the produced water is quickly discharged, and the concentrated water is quickly drained. Exhaust valve, ultrafiltration water pump and adding reducing agent metering pump; open the water inlet valve, ultrafiltration water pump, high pressure pump, adding reducing agent metering pump and adding antiscalant metering pump when making water; water inlet valve when high pressure flushing when shutting down, Open the product water quick discharge valve, concentrated water quick discharge valve, ultrafiltration water pump, high pressure pump, reducing agent metering pump and scale inhibitor metering pump; open the product water quick discharge valve and concentrated water quick discharge valve when shutting down for low-pressure flushing, Flush the inlet valve and low-pressure flushing pump. 4. An unattended intelligent control system for desalinated water production process according to claim 1, characterized in that, when the mixed bed device discharges water, the upper drain valve and exhaust valve are opened; when it fails, the alkali inlet valve is opened, and the outlet valve Alkali valve, water inlet valve and regenerated water pump; open the backwash water inlet valve, backwash drain valve and intermediate water pump when backwashing is stratified; close all valves and pumps when settling; open the upper drain valve and exhaust valve when releasing water; metering Open the acid inlet valve and alkali inlet valve during calibration; open the acid inlet valve, alkali inlet valve, regeneration discharge valve, acid outlet valve, water inlet valve, alkali outlet valve, water inlet valve and regeneration water pump when regenerant is fed; inject calibration Close all valves and pumps when nuclear; open the acid inlet valve, alkali inlet valve, regeneration drain valve, water inlet valve, water inlet valve and regeneration pump when replacing; open the upper drain valve and exhaust valve when releasing water; when air is mixed, Open the backwash drain valve, intake valve and exhaust valve; open the intake valve, exhaust valve and intermediate water pump when filling water; open the intake valve and drain valve for forward washing; instrument connection valve, unqualified return water valve and intermediate water pumps; close all valves and pumps when not in use. 5. The unattended intelligent control system for a desalinated water production process according to claim 1, wherein the operator screen alarm of the man-machine interface alarm of the alarm system is divided into alarm history information and flow chart screen alarm, The historical information provides detailed alarm records, and the flowchart screen alarm provides intuitive and accurate alarm locations. 6. The unattended intelligent control system for desalinated water production process according to claim 1, characterized in that, the alarm system has an audible and visual alarm, and when an alarm occurs, the DCS or PLC controller passes through the I/O card The alarm signal is sent to the sound and light alarm through the wire, and the different alarm levels are indicated by different alarm sounds, and the operator is prompted. 7. The unattended intelligent control system for desalinated water production process according to claim 1, characterized in that, the SMS alarm of the alarm system, alarm information such as equipment failure, is sent to maintenance personnel through the alarm SMS platform.