Automatic Quartz Sand Filter,activity Carbon Filter,softening and Primary Reverse Osmosis Precision Filter PLC Pure Water System

Product description

1、 Core components and functions of the system
1. Fully automatic quartz sand filter
Function: Through the interception effect of quartz sand filter material, large particle impurities such as suspended solids, sediment, rust, colloids, etc. in raw water are removed, reducing turbidity (usually from 20NTU to below 5NTU).
Automated design:
Equipped with a PLC control system, it can automatically execute the filtration → backwashing → forward washing process.
Backwash triggering conditions: pressure difference>0.05MPa or timed (such as once a day), backwash intensity 15-20L/(m ² · s), taking 5-10 minutes.
Filter material parameters: quartz sand particle size 0.5-1.2mm, filter layer thickness 1000-1500mm, filtration flow rate 5-10m/h.
2. Activated carbon filter
Function: Utilizing the adsorption capacity of activated carbon, remove residual chlorine, organic compounds (such as benzene and phenol), pigments, and odors from water, and reduce TOC (total organic carbon) to ≤ 2mg/L.
Key technical points:
Using coconut shell activated carbon (specific surface area ≥ 1200m ²/g), the adsorption efficiency of residual chlorine is greater than 99%.
Automatically monitor the residual chlorine in the inlet water. When the residual chlorine in the outlet water exceeds 0.1mg/L, the PLC triggers an alarm and prompts to replace the activated carbon (usually every year).
3. Softening device
Function: Remove calcium (Ca ² ⁺) and magnesium (Mg ² ⁺) ions from water through ion exchange resin, reduce hardness (such as from 300mg/L to below 5mg/L), and prevent reverse osmosis membrane fouling.
Automated regeneration:
Use time/flow triggered regeneration (such as every 100m ³ of water treated or once a week).
Regeneration process: backwashing (removing impurities from the resin layer) → salt absorption (NaCl solution concentration 8% -10%) → slow washing → forward washing, the entire process takes about 90 minutes.
4. First stage reverse osmosis (RO) system
Function: Driven by a high-pressure pump (0.8-1.5MPa), deep desalination is achieved through a reverse osmosis membrane to remove dissolved salts, bacteria, viruses, etc. The desalination rate is 95% -98%, and the conductivity of the produced water is ≤ 50 μ S/cm (when the TDS of the raw water is less than 2000mg/L).
Core components:
Membrane element: Roll type composite membrane (such as Dow BW30-400), with a single membrane production capacity of 1m ³/h and a service life of 3-5 years.
Concentrated water control: Automatically adjust the concentrated water valve to control the recovery rate of 60% -80%. The concentrated water can flow back to the pre-treatment front end (supported by some systems).
5. Precision filter (security filter)
Function: Installed in front of the RO membrane, with a filtration accuracy of 5 μ m, it intercepts small particles and colloids (such as silica particles) remaining after pretreatment, protecting the RO membrane from physical damage.
Filter type: PP melt blown filter, replacement cycle 1-3 months (when pressure difference>0.1MPa), supports quick replacement design.
6. PLC control system
Core functions:
Integrated human-machine interface (HMI), real-time display of parameters such as pressure, flow rate, conductivity, liquid level, etc.

Automatic linkage of various devices:
The backwashing and softening regeneration of sand/carbon filters should be staggered to avoid water flow impact.
The RO system dynamically adjusts based on the water tank level (low level start, high level stop) and water quality (automatic flushing when conductivity exceeds the standard).
Fault alarm: When the high-pressure pump is overloaded or the membrane pressure difference exceeds the limit, it will automatically shut down and sound an audible and visual alarm.

2、 System Process and Water Quality Standards
1. Complete processing flow
plaintext
Raw water → Fully automatic quartz sand filter (to remove large particles) → Activated carbon filter (to remove residual chlorine/organic matter) → Softening device (to remove hardness) → Precision filter (5 μ m) → Primary reverse osmosis (desalination) → Pure water tank → Water point
2. Progressive effect of water quality
Turbidity (NTU), residual chlorine (mg/L), hardness (CaCO3, mg/L), conductivity (μ S/cm) during the processing stage
Raw water ≤ 20 ≤ 1.0 ≤ 500 ≤ 2000
Sand filtration+carbon filtration ≤ 5 ≤ 0.1 ≤ 500 ≤ 1800
Softened ≤ 5 ≤ 0.1 ≤ 5 ≤ 1800
RO water production ≤ 1 ≤ 0.05 ≤ 1 ≤ 50
3. Scope of compliance
The produced water meets the GB/T 11446.3-2013 electronic grade water III standard or GB 5749 hygiene standard for drinking water (adjustable according to demand).
3、 Application scenarios and advantages
1. Typical application areas
Industrial pure water:
Electronic industry: Cleaning water for circuit boards (conductivity ≤ 10 μ S/cm).
Food and beverage: production water (such as beer brewing, in accordance with GB 5749).
Chemical industry: process water (such as coating preparation, reducing ion interference).
Civilian water purification:
Direct drinking water system in the community (producing water for direct consumption).
Commercial water purification equipment (centralized water supply for schools and hospitals).
Special Scenario:
Groundwater iron and manganese removal (with manganese sand filter pretreatment).
High hardness water softening (such as boiler water in northern regions).
2. System advantages
Advantageous technology implementation
Fully automated operation of PLC linkage with various equipment, without the need for manual intervention, reducing the risk of human error.
Stable and reliable water quality with multi-stage filtration and real-time monitoring to cope with fluctuations in raw water quality (such as increased turbidity during the rainy season).
Low operation and maintenance cost sand filter/carbon filter automatic backwash, softening automatic regeneration, RO membrane life extended to 5 years (under routine maintenance).
Energy saving design with variable frequency control for high-pressure pumps, with an average energy consumption of 1.5 kWh/m ³, saving 20% energy compared to traditional systems.

4、 Maintenance and troubleshooting
1. Regular maintenance plan
Component maintenance content cycle
Check the loss of filter material in quartz sand filter and replenish quartz sand every six months
Activated carbon filter replacement of activated carbon filter material every year
Softening resin testing resin exchange capacity, supplementing or replacing resin every 2-3 years
Chemical cleaning of RO membrane components (acid descaling/alkaline organic matter removal) every 6-12 months
Clean the dust in the control cabinet of the PLC control system and check the wiring terminals quarterly
2. Common faults and solutions
Possible causes and solutions for the fault phenomenon
RO water production decreases due to membrane fouling/insufficient pressure of high-pressure pump, chemical cleaning of membrane/checking of pump group pressure
Softened water with excessive hardness, resin failure/insufficient regenerated salt content, resin replacement/adjustment of regenerated salt concentration
Activated carbon filter odor filter material adsorption saturation/sudden increase in organic matter in raw water Replace activated carbon/strengthen front-end pretreatment
5、 Selection and configuration suggestions
1. Select based on water production rate
Small scale system: 1-10m ³/h, suitable for laboratories and small factories, with equipment power of 5-15kW.
Medium sized system: 20-50m ³/h, suitable for residential areas and food factories, requiring a 50-100m ³ pure water tank.
Large scale system:>100m ³/h, using multiple sets of RO in parallel, equipped with a central monitoring platform.
2. Raw water enhanced pretreatment configuration
High turbidity raw water (>10NTU): Add flocculation dosing device (PAC/PAM)+sedimentation tank.
High sulfate raw water (SO ₄² ⁻>500mg/L): The softener uses sulfate type resin or adds scale inhibitors.
Seawater/high salt well water (TDS>3000mg/L): Upgrade to secondary reverse osmosis or combine with EDI electro deionization.
3. Intelligent upgrade
Connect to the Internet of Things (IoT) platform to achieve remote monitoring (such as viewing operational data and fault warnings through mobile apps).
Configure a concentrated water recovery system to increase the total water utilization rate to over 85% through concentrated water RO (in scenarios with high environmental requirements).
summarize
The pure water system controlled by this PLC achieves efficient purification from raw water to pure water through a combination of “fully automatic pretreatment+primary RO desalination”, suitable for scenarios with high requirements for automation and water quality stability. Its core value lies in the intelligent control of the entire process, efficient multi-level filtering collaboration, and convenient operation and maintenance management, making it an ideal solution for industrial production and civilian water purification. Users can flexibly adjust the pretreatment process and RO configuration according to the quality of raw water and water demand, in order to achieve the best cost-effectiveness.