Raw water tank raw water pump multi-media filter activated carbon filter softener regeneration system heat exchanger temperature sensor pressure gauge sensor flowmeter，security filter heat exchanger a high pressure pumps a reverse osmosis device two high pressure pump two reverse osmosis device.
Continuous Electrolysis Unit (CEDI) Sodium Dioxide Dosing System Flowmeter Conductivity Sensor Temperature Sensor Pressure Sensor.
Online PH detector manual and automatic valve electrical cabinet.
The system is used for the purification of water preparation system, including: raw water tank, multi-media filter, activated carbon filter, softener, RO device, EDI device. The following key process steps are described
Purified water preparation system as a whole using PLC control, man-machine dialogue interface (HMI) for the touch screen, you can achieve independent operation. Include.
Automatic:Automatically contains normal water, cleaning, unqualified emissions, sterilization and so on. Normal water from the drinking water into the original water tank, after sand filter carbon filter, softening, RO and EDI, the output of the standard purified water, into the purified water tank. When the purified water is detected by the instrument is not qualified, the automatic discharge.
1. Raw water system: drinking water into the original water tank, after the original pump, the water hit the multi-media filter.
2. Pretreatment system: The pretreatment system consists of a multi-media filter and an activated carbon filter. The multi-media filter filters large particles and impurities in the water. Activated carbon filter.
3. Filter the polymer organic matter and residual chlorine. Under normal circumstances, the cumulative work 24H must be cleaned.
4. Softening system: softening system to remove calcium and magnesium ions, etc., to reduce the hardness of water. Under normal circumstances, continuous work 24H for cleaning and softening.
5. Heat transfer system: the activated carbon pasteurization, to provide temperature; in the cold weather, to meet the RO water temperature of 25 degrees.
6. RO system; remove all kinds of ions, reduce conductivity and TOC.
7. EDI system: to further remove the various ions, reduce the conductivity and TOC. Output qualified purified water.
The original water tank is the municipal water container, the material 304, the water tank volume is 1000L. The liquid level transmitter (LT3101) can send the signal to the PLC, we can through the PLC in the tank level high and low, control the pneumatic valve (AV3101) off and open. When the water in the original tank is contaminated, the drain valve (HV3102) can be opened for discharge.
(2)Raw Water Pump
The raw water pump (PU3101) runs continuously in the equipment. The pump is equipped with a frequency converter (VSD3101). The operation of the original pump is controlled by the inverter. When the anti-wash multi-media, activated carbon filter, the original pump (PU3101) running flow of about XXXT / hr. When the softener regeneration, the original pump flow will be increased accordingly to meet the needs of the system. The above functions are realized by the inverter automatic control. The valves (HV3103) and (HV3104) are always open when the system is running, and we can adjust the flow and pressure at the outlet of the original pump through these two valves. The sampling valve (SV3101) is only used for raw water sampling. The pressure gauge (PI3101) can show the outlet pressure of the original pump (PU3101).
During operation, the raw water enters the multi-media filter through the pneumatic valve (AV3102) and is discharged from the pneumatic valve (AV3106). When the backwash cycle time of the multi-media filter is reached (the backwash period is generally 24 hours, the HMI parameter can be set by itself). At this time, the multi-media enters the backwash mode, and the pneumatic valves (AV3104 and AV3103) will open. Wash time to reach (backwash time is generally 5min, in the HMI parameter settings can be set) to enter the wash mode. In this case, the multi-media enters the positive wash mode. The pneumatic valves (AV3102 and AV3105) will open. When the wash time is reached (the time of the washing is 5min, the HMI parameter can be set by itself), the device enters the running state.
The softening section is actually a set of two units consisting of two ion exchangers (filters) connected in series, each of which can handle 100% of the flow. In the softener filled with special cation exchange resin, calcium and magnesium ions will be sodium ions, but the total salt content of water unchanged.
Softener (F3201) as the main working softener and softener (F3202) as the softener. When the softener (F3201) resin is regenerated, the softener (F3202) acts as the main working softener and the softener (F3201) acts as a delicate softener. Softening resin regeneration can be set according to the length of time to set, can also be generated according to the amount of softened water control. When the time to reach the set point (the regeneration cycle is generally 24h, the HMI parameter settings can be set), the softener will automatically start the regeneration process to complete the regeneration process. When the regeneration set point is reached, the regeneration program of the main softener (F3201) is activated. During the regeneration of the main softener (F3201), the valve (AV3208) is opened and the valve (AV3202) is closed to allow the influent to flow into the refining softener (F3202), at which the softener will be the sole softener. This softening system and the overall purified water preparation device can be operated continuously. Upon completion of the regeneration, the main softener (F3201) to restore its function, continue normal operation. The regeneration process of the two softeners is interlocked so that the two softeners are not regenerated at the same time.
During the regeneration of the softener (F3202), the valves (AV3202, AV3206) are opened and the valves (AV3208, AV3212) are closed to allow the demineralized water flowing out of the main softener (F3201) to enter the RO system directly. After regeneration, the Refiner Softener (F3202) returns to its normal operating condition.
The chemicals used for regeneration are sodium chloride (salt). Need to be provided in solid (flaky or spherical). A nearly completely saturated (26%) salt solution was formed at the bottom of the salt box (TK3201) and the solution was injected into the corresponding softener during regeneration. Salt tank can be dissolved by automatic water to dissolve sodium chloride.
(5)Valves and Instrument of Multi Media Filter
The pressure gauge (PI3102) and (PIS3103) can show the inlet and outlet pressure of the multi-media filter when the system is running. When the inlet and outlet pressure difference increases by 10%, this means that we need to wash the filter. The valve (HV3107) is only used for the discharge of water inside the filter at a particular time. We can take a water sample from the valve (SV3102) to detect the turbidity of the water produced by the multi-media filter
Recycle, Back Washing and Absorbing Salt
The softener (F3202) operates separately when the softener (F3201) needs to be regenerated. When the valve (AV3202, AV3206) is turned off and the valve (AV3210, AV3203) is open, the softener (F3201) is backwashed when the softener (F3202) is running. The flushing time can be set on the HMI (rinse time is recommended 5 -10 minutes). (AV3213, AV320, AV3201, AV3205) open, adjust the valve (HV3220, HV3221, HV3222, HV3223) to make the brine flow to meet the demand. The resin and salt water contact time is usually set by the HMI (usually around 45 minutes).
(F3201) into the flushing state, the valve (AV3213, AV3201, AV3205) open, then softener (F3201) slow wash, the time can be set in the HMI (slow wash time recommended 5-10 minutes ). The purpose is to flush the pipeline and the remaining brine in the tank to protect the pipeline from salt water corrosion. (AV32013, AV3201) is turned off, the valve (AV3202, AV3205) is open, the softener (F3201) is quick-cleaned, the time can be set on the HMI itself (quick wash time is recommended 20-30 minutes) , The purpose is to rinse the softener (F3201) residual brine.
At the end of the rinse, the salt box is in a dry state and the valve (AV3213, AV3214) opens to the salt tank. After the salt level reaches the high level, the level switch (LSA3201) passes the signal to the PLC, and the PLC stops the valve (AV3213, AV3214). After the end of each regeneration in the salt box to add enough salt, in the next regeneration before the full dissolution, the formation of saturated salt water.
(7)Softener Manual Valves
The valves (HV3216, HV3220, HV3221, HV3222, HV3223) are not adjusted until they are run at the beginning of the commissioning. Valve (HV3214, HV3215) is used in certain circumstances, such as the softener regeneration, the tank has a residual pressure caused by salt flow is too small to open the pressure relief. The valves (HV3217, HV3218) are only used for the discharge of water inside the filter at a particular time.
(8)Pressure Sensors and Sampling
The pressure sensor (PT3201) can maintain the pressure of the filtered water by adjusting the frequency of the original pump (PU3101). We can take water samples from the valves (SV3201) and (SV3202) to detect the hardness of the water after the softener.
Note: The softener (F3202) needs to be regenerated when the valve is switched to the softener (F3201)
(9)Activated Carbon Filters
During operation, the raw water enters the multi-media filter through the pneumatic valve (AV3301) and is discharged from the pneumatic valve (AV3105). When the backwash cycle time of the multi-media filter arrives (the backwash period is generally 24 hours, the HMI parameter setting can be set by itself). At this time, the multi-media enters the backwash mode, and the pneumatic valves (AV3302 and AV3303) will open. Wash time to reach (backwash time is generally 5min, in the HMI parameter settings can be set) to enter the wash mode. In this case, the multi-media enters the positive wash mode. The pneumatic valves (AV3301 and AV3104) will open and the device will enter the running state when the wash time is reached (the washing time is usually 5min and the HMI parameter can be set by itself).
(10)Valves and Instrument of Activated Carbon Filter
The pressure gauge (PI3104) and (PIS3105) can show the inlet and outlet pressure of the activated carbon filter when the system is running. When the inlet and outlet pressure difference increases by 10%, this means that we need to wash the filter. The valve (HV3301) is only used for the discharge of water inside the filter at a particular time. We can take the water from the valve (SV3301) to detect the residual chlorine value of the activated carbon filter.
The water from the raw water pump is passed through the valve (HV3401) and heated to 25 ° C in the heat exchanger (HE3401), which is then conveyed to the multi-media filter. The water temperature control at 25 ℃ or so can make the system the maximum water production.
(12)Multi Media, Activated Carbon and Pasteurizatio
If the filter needs pasteurization, the valve (AV3405) should be closed first. The water level of the original water tank will be activated when the water level of the water tank is 1/3, the water inlet valve (AV3101) will be closed, the valve (AV3102, AV3106, AV3207, AV3207, AV3301, AV3305 and AV3404) will be opened. The water circulates in the original water tank, quartz sand and activated carbon filter. Through the heat exchanger (HE3401) gradually in the process of circulation reached 85 ℃, the cycle time is about 90 to 120 minutes. The temperature of circulating water can be monitored through the temperature transmitter (TT3402). Heat exchanger inlet temperature of 80 ℃, the temperature transducer (TT3401) will put the timing signal output to the PLC. Finish the original pump (PU3101) and close the pneumatic valve (AV3402). The cooling process can be cooled by cooling water or allowing the system to circulate naturally. After hot water cooled to 50 ℃ below, (AV3304) to open the drain valve.
(13)Valves and Instrument of Sterilization System
If the filter needs to be pasteurized, first turn off the valve (AV3405). (AV3102, AV3106, AV3207, AV3208, AV3301, AV3305 and AV3404) are turned on when the original water tank is in the water tank volume of 1/3. The water circulates in the original water tank, quartz sand, activated carbon filter. Through the heat exchanger (HE3401) in the process of circulation gradually reach 85 ℃, the cycle time is about 90 to 120 minutes. The temperature of the circulating water can be monitored by the temperature transmitter (TT3402). The inlet temperature of the heat exchanger reaches 80 ° C and the temperature transmitter (TT3401) will output the signal to the PLC. The pump (PU3101) continues to run and the pneumatic valve (AV3402) is closed. At this time into the cooling discharge state, in the cooling process can be cooled by external cooling water, or let the system natural circulation cooling. After the hot water is cooled below 50 ° C, the valve (AV3304) can open the drain.
Main Machine Operation Instructions
The water flowing from the softener (F3301) enters the safety filter (F3401), which is used to remove any remaining coarse particles that may affect the RO element. This filter is fitted with a 5 μm filter with length high accuracy.
The pressure gauge (PI3401) and the pressure gauge (PI3402) can show the inlet and outlet pressure of the filter (F3401). When the pressure difference between the two pressure gauges reaches one kilogram, we need to replace the filter cartridge as soon as possible. The water flowing out of the safety filter drops the inlet pressure to a set value before reaching the primary RO high pressure pump (PU3401) to ensure the stability of the RO high pressure pump suction side. The pneumatic valve (AV3405) is used to isolate (close) the reverse osmosis phase.
The pressure on the outlet side of the safety filter can be measured by the pressure gauge (PI3402) and can be compared with the inlet pressure indicated by the pressure gauge (PI3401) to check the condition of the filter element. The sampling valve (SV3401) is used to collect water samples from the filter outlet side.
(2)High Pressure Pump of Primary RO
The pressure and flow of water before entering the primary RO unit can be measured by means of a flow meter (FI3401) and a pressure gauge (PI3403). The high-pressure pump is controlled by the inverter (VSD3401), and the inverter can be adjusted according to the high-pressure pump outlet pressure or the RO outlet flow rate. According to the system design a RO production water should be maintained at about XXXm3 / hr. The primary RO water flow can be measured by the flow meter (FE3403). Level 1 RO concentration should be kept at about XXXm3 / hr. The RO flow rate of the primary RO can be measured by a flow meter (FI3402). Water is pumped into the primary RO unit in high pressure by means of vertical, multistage, speed controlled centrifugal pumps (PU3302).
The valve (HV3406) always opens when the system is running, and we can use this valve to adjust the flow and pressure at the outlet of the high-pressure pump. We can take water samples from valves (SV3402A, SV3402B, SV3402C, SV3402D, SV3402E, SV3403) to detect the water quality of each pressure vessel or total water.
Pressure gauge (PI3306), pressure transmitter (PT3305) can reflect the high-pressure pump outlet pressure.
(4)Primary Reverse Osmosis Device
All the installation pipes in the system are made of stainless steel. The reverse osmosis unit is used to remove ions from the softened water and operate according to the principle of reverse osmosis. The filtered water enters the membrane module (pressure vessel RO3401A, RO3401B, RO3401C, RO3401D, RO3401E) through the frequency conversion pump (PU3401) in high pressure. Part of the water through the RO membrane components at the same time the dissolved solids in the water and other impurities remain in the concentrated water. Water through the RO membrane element is called fresh water (osmotic water). In normal operation, the membrane in the reverse osmosis unit may be blocked due to mineral scale, biomass, colloidal particles and insoluble organic matter. During the course of the process, the membrane surface accumulates dirt until it leads to normal osmotic water production, reduced normal salt removal, or both.
When the parameters are as follows, the membrane module should be cleaned: the normal infiltration water flow is reduced by 10-15%, the normal salt pass rate is increased by 5-10%; the normal pressure drop (water pressure minus the concentrate pressure) rises 10-15%.
The water conversion coefficient WCF can be adjusted by means of a concentrate control valve (HV3409). Some of the concentrated water is discharged to the RO pump before. The relative yield of permeated water (corresponding to WCF) should normally be about 70% of the raw water entering the system. The conductivity meter (CT3402) in the reverse osmosis unit is used to monitor the quality of the permeate. When the water conductivity is higher than the set value, the valve (AV3410) is open, the valve (AV3411) is closed, and the primary RO is not qualified for water discharge. When the water is finished, the valve (AV3411) is opened and the valve (AV3410) is closed. In this case, the valve should be closed and closed. Conductivity meter (CT3301) is used to monitor the conductivity of raw water, when the original water conductivity exceeds the set value, the system will alarm.
The valve (AV3407) is opened when the system is turned on and the flush time is set for about 2 minutes. Purpose To rinse the RO membrane side, fill the pipe and pressure vessel with water. At this point the system only to start the original pump, high pressure pump when the valve (AV3407) closed.
(6)High Pressure Pump of Secondary RO
The pressure and flow rate of water before entering the secondary RO unit can be measured by means of a flow meter (FE3403) and a pressure gauge (PE3407). The high-pressure pump is controlled by the inverter (VSD3302). According to the system design two RO production water should be maintained at about XXXm3 / hr. The secondary RO water flow can be measured by a flow meter (FIT3102). In order to ensure the water production, the secondary RO high pressure pump (PU3303) can be connected with the secondary RO flow meter (FE3404) or the secondary RO high pressure pump (PU3303) outlet pressure transmitter (PE3408), pressure transmitter (PE3407) Used to monitor the secondary RO high pressure pump inlet pressure, the pressure does not meet the requirements, the system will issue a shutdown alarm. Water is pumped into the secondary RO unit in high pressure by means of vertical, multistage, speed controlled centrifugal pumps (PU3402).
(RO3302) contains XXX RO components in each film shell, the same type and type of each component.
The valve (HV3412) always opens when the system is running, and we can use this valve to adjust the flow and pressure at the outlet of the secondary high-pressure pump. We can take water from the valve (SV3404) to detect the water quality of the water.
(7)Secondary Reverse Osmosis Device
The secondary reverse osmosis unit is used to further remove the ions in the primary fresh water and operate according to the principle of reverse osmosis. The water filtered through the primary RO enters the membrane module (pressure vessel RO3302) in high pressure through the frequency control pump (PU3402). Part of the water through the RO membrane components at the same time the dissolved solids in the water and other impurities remain in the concentrated water. Before passing through the valve (HV3413) into the primary high-pressure pump (PU3402). The water conversion coefficient WCF can be adjusted. The conductivity meter (CT3403) of the secondary reverse osmosis unit is used to monitor the quality of the permeate. If the conductivity exceeds the pre-set value, the alarm will be displayed on the electrical cabinet, and the valve (AV3315) will open and the valve (AV3316) will close and the system will enter the flush program and be closed.
The pressure of the secondary RO effluent is monitored by the pressure sensor (PE3411). If the secondary RO water pressure is too high, EDI module will be damaged. If the secondary RO water pressure is too low, you cannot meet the requirements of the follow-up system, so here will set the alarm. If the pressure is higher than the set upper limit or below the set lower limit, an alarm will be issued and the system will be shut down.
The permeate from the secondary reverse osmosis unit enters the deionization module (EDI 3401). Fresh water from the EDI module passes through the valves (AV3420, AV3423) through two pipelines into the pure water tank. The flow direction in the two pipelines is the same. If the conductivity of fresh water exceeds the set value. An alarm is displayed on the electrical cabinet, the system enters the flush program and is closed.
The EDI module generates a small amount of hydrogen ions and hydroxide ions for regeneration of the ion exchange resin in the module. The high pH and low pH values generated in the EDI module can control microbial growth at very low levels during operation.
The conductivity and temperature of fresh water can be continuously monitored by the conductivity meter (CE3404). If the conductivity of fresh water is below the set value, the valve (AV3420, AV3423) opens and fresh water flows into the pure water tank. If the conductivity is higher than the set value, the valve (AV3422) opens and the valve (AV3420, AV3423) is closed. The flow of fresh water can be measured by a flow meter (FE3406). The flow rate of concentrated water is measured by a flow meter (FIS3405). The flowmeter (FIS3405) has a low limit switch and the concentrated water flow rate is below the set value. The alarm then shuts down the power supply to the EDI system.
When the pure water tank full level, the pure water tank in the liquid level transmitter will send a signal to the control cabinet. The valve (AV3420, AV3423) will turn off and the valve (AV3421) will open and the system will run in cycle mode. At this point the efficiency of the system cycle operation is about 70-80% of normal operation.
(10)Manual Valves and Pressure Gage of EDI System
Manual valves (HV3416, HV3417) are located in the EDI module import and export, these valves can adjust the operating pressure and flow of EDI systems, these valves are always open and we can adjust these valves when the system tests. And the valve (HV3418) can adjust the EDI water flow meter (FIS3405) and the pressure (PI 3412). Valves (HV3419) can be adjusted for EDI fresh water flowmeters (FE3406) and pressure (PI 3413).
You can select various operating modes on the HMI (see the program flow chart for each procedure step).
Cycle flush: When the system is running in batch mode, there will be a period of time the system does not generate pure water. If the water in the pipeline remains stationary, it increases the risk of microbial growth. In order to minimize this risk, the system will automatically switch to the cycle mode after the pure water tank is full. The valves (AV3420, AV3322, AV3323) are closed and the water is circulated through the valve (AV3421). If the conductivity monitored by the Conductivity Meter (CE3404) rises above the set value (can be set via HMI) during the cycle, the water is automatically discharged from the valve (AV3422). When the level in the pure water tank is reduced, the system returns to normal operation mode.
The intermittent flush mode is used to replace the cycle flush mode, and the system can be set to rinse at a certain time interval. In this mode, the system is automatically started after an adjustable set of idle periods and has been rinsed for 15 minutes through the valve (AV3414) and the flushing water is drained into the drainage system. The system then returns to standby mode.
Rinse: The concentrated salt side of the reverse osmosis pressure vessel (RO3301-RO3301B), where the mineral salt is deposited. Because the softened water will remain in the pressure vessel when the system is suddenly closed, so any of the particles will precipitate onto the membrane and the dissolved salt will crystallize from the softened water. This will have a negative impact on the system performance and even damage the film. In order to avoid the occurrence of such things, the system has a rinse function, the reverse osmosis device switch automatically flush the membrane side of the water.
If the "RO fresh water conductivity is too high" and other alarm or in the "intermittent rinse mode" when running after a pre-set idle period, the system will start the washing process. The reverse osmosis unit will be flushed through the valve (AV3414). Finally, the system pressure is released through the valve (AV3415).
Quality: In order to ensure good microbial quality in the water, the entire system remains active even after the tank level is full. At this stage, the system is continuously circulated to ensure that the piping between the purified water preparation system and the tank can be continuously flushed.
(12)Sodium Hydroxide Adding Device
The purpose of the addition of sodium hydroxide is to remove it by converting carbon dioxide (CO2) to bicarbonate (HCO3-) under high pH conditions. This compact pump is installed on the medicine box. Sodium hydroxide was injected through a dosing pump (PU3403). The sodium hydroxide dosing device also includes a microprocessor-controlled electromagnetic pump (PU3403) with a suction assembly and a liquid level switch (LSA3401) and a sodium hydroxide jar (TK3302) linked to it, Control the pH transmitter (PHT3301) on the control panel. Dosing rate can be adjusted by external signal, the target pH value of 7.8-8.2. The pH transmitter mounted on the control panel allows continuous control of the dosing procedure.