Raw Water tank Sand Filter, Carbon Filter, Fine Filter, Fully Automatic Reverse Osmosis with Pure Water tank

Product description

Raw water tank equipped with sand filter, carbon filter, fine filter and fully automatic reverse osmosis with pure water tank water treatment system
1、 System composition and process flow diagram
This system is an integrated water treatment solution that achieves the conversion of water quality from turbid water to pure water through a full process design of “raw water storage multi-stage filtration reverse osmosis desalination pure water storage”. The core components and processes are as follows:
plaintext
Raw water tank → Sand filter → Carbon filter → Fine filter → Fully automatic reverse osmosis device → Pure water tank → Water point
System architecture:
Preprocessing unit: three-stage filtration including sand filtration, carbon filtration, and fine filtration, to remove suspended solids, organic matter, residual chlorine, and fine particles;
Desalination unit: fully automatic reverse osmosis device for deep removal of dissolved salts;
Storage unit: Raw water tank and pure water tank, balancing water quality and quantity fluctuations.
2、 Technical principles and functions of each unit
1. Raw Water Tank
Function: Store raw water, buffer fluctuations in water quality and quantity (such as unstable raw water supply), and create stable conditions for subsequent treatment.
Design parameters:
Material: Q235B anti-corrosion coating or 304 stainless steel, designed with a capacity of 1-2 times the system’s water production (such as a 10m ³/h system with a 10-20m ³ water tank);
Supporting equipment: level gauge, inlet valve, drain valve, can be integrated with PLC automatic control (low level alarm, high level pump stop).
2. Sand Filter
Principle: Quartz sand (particle size 0.5-1.2mm) removes large impurities such as sediment and rust through physical interception, reducing turbidity to ≤ 5NTU.
Automated control:
Pressure difference triggers backwashing (>0.05MPa) or timed (8-12 hours), with a backwashing intensity of 15-20L/(m ² · s), lasting for 5-10 minutes;
The backwash water source comes from a pure water tank or raw water (depending on the water quality), saving water resources.
3. Carbon Filter
Principle: Coconut shell activated carbon (specific surface area ≥ 1000m ²/g) removes residual chlorine (removal rate>99%), organic matter, and off color odors through adsorption, protecting the RO membrane.
Key parameters:
Contact time 10-15 minutes, residual chlorine in effluent ≤ 0.05mg/L;
Activated carbon filling density is 800-1000kg/m ³, with a replacement cycle of 1-2 years.
4. Fine Filter
Principle: The 5 μ m PP melt blown filter element intercepts fine particles and colloids remaining after pretreatment, ensuring that the inlet SDI is ≤ 5 and preventing clogging of the RO membrane.
Maintenance logic: If the pressure difference is greater than 0.1MPa or the filter element needs to be replaced after 1-3 months of operation, the quick opening structure is easy to operate.

5. Fully Automatic RO Device
Principle: The high-pressure pump (0.8-1.5MPa) drives the raw water to pass through the RO membrane (pore size 0.0001 μ m), with a desalination rate of ≥ 95% and a produced water conductivity of ≤ 50 μ S/cm.
Automated design:
PLC control for start stop and flushing (low pressure flushing for 1 minute upon startup, chemical flushing for 5 minutes upon shutdown);
Real time monitoring of water conductivity and automatic discharge when exceeding the standard;
Concentrated water reflux control, with a recovery rate of 60% -80% (such as 6-8m ³/h for a 10m ³/h system and 2-4m ³/h for concentrated water).
6. Pure Water Tank
Function: Store RO produced water to meet the continuous demand of water points, made of 304/316L stainless steel, with inner wall electrolytic polishing (Ra ≤ 0.6 μ m).
Supporting equipment:
Liquid level control (low liquid level starts RO, high liquid level stops);
Air respirator, CIP cleaning system (regularly disinfected to prevent microbial growth);
The volume is designed to be 2-4 times the water production rate (such as a 10m ³/h system with a 20-40m ³ water tank).
3、 Comparison of Water Quality Treatment Effects
Turbidity (NTU), residual chlorine (mg/L), hardness (CaCO3, mg/L), conductivity (μ S/cm), TDS (mg/L) during the processing stage
Raw water ≤ 20 ≤ 1.0 ≤ 500 ≤ 2000 ≤ 1000
After sand filtration, ≤ 5 ≤ 0.5 ≤ 500 ≤ 1800 ≤ 900
After carbon filtration, ≤ 3 ≤ 0.05 ≤ 500 ≤ 1500 ≤ 750
After fine filtration, ≤ 1 ≤ 0.05 ≤ 500 ≤ 1500 ≤ 750
RO water production ≤ 0.5 ≤ 0.02 ≤ 5 ≤ 50 ≤ 30

4、 Application scenarios
Industrial production water
Electronics industry: chip cleaning water (conductivity ≤ 10 μ S/cm), matched with EDI to produce ultrapure water;
Pharmaceutical industry: Preparation of purified water (compliant with GMP standards) for use in formulations and equipment cleaning;
Food and beverage: water for beverage preparation and sterile filling, meeting the GB 5749-2022 standard.
Civil and Municipal Scenarios
Direct drinking water system in residential areas: water conductivity ≤ 50 μ S/cm, equipped with ultraviolet sterilization, supporting pipeline quality water supply;
Rural drinking water renovation: treating high hardness and high turbidity groundwater to solve scale and microbial problems.
Special fields
Laboratory: As a basic equipment for pure water (later compatible with ultrapure water machines);
Offshore platform: Pre treatment of seawater desalination (requiring sand filtration and carbon filtration to remove suspended solids and residual chlorine).
5、 System advantages and innovative design
Fully automated collaborative control
Linkage between raw water tank and RO device: When the liquid level in the raw water tank is low, the RO will automatically shut down to avoid pump idling;
The pure water tank level is interlocked with RO start stop to achieve closed-loop control of “water production storage water use”, reducing manual intervention.
Anti pollution and long-life design
Pre treatment three-stage filtration: sand filtration to remove large particles, charcoal filtration to remove organic matter, fine filtration to prevent membrane fouling, and RO membrane cleaning cycle extended to 6-12 months;
Install a drain valve in the raw water tank to regularly remove sediment at the bottom and reduce pre-treatment load.
Energy saving and environmental optimization
Variable frequency control of high-pressure pump: energy consumption of 1.5-2kWh/m ³, saving 20% energy compared to traditional systems;
Concentrated water recovery: When TDS<1000mg/L, it can be reused for green irrigation, and the water resource utilization rate can be increased to over 85%.
6、 Maintenance points and troubleshooting
1. Regular maintenance plan
Component maintenance content cycle
Clean and disinfect the raw water tank/pure water tank, and verify the liquid level sensor every quarter
Check the loss of filter material in sand/carbon filters, replenish/replace sand filters every six months, and replace carbon filters every year
Replace the filter element of the fine filter every 1-3 months
RO membrane element chemical cleaning (citric acid+sodium hydroxide) every 6-12 months
2. Common troubleshooting solutions
Possible causes and solutions for the fault phenomenon
RO water production decreases due to membrane fouling/low inlet water temperature for chemical cleaning/raising water temperature to above 15 ℃
Deterioration of water quality in pure water tank, insufficient disinfection of water tank/blockage of air respirator, strengthening of CIP cleaning/replacement of filter element
Sudden increase in pressure difference of fine filter, sudden pollution of raw water/clogged filter element, replacement of filter element/investigation of upstream water quality

7、 Selection and configuration suggestions
Design of Water Production and Tank Capacity
Small scale system: 1-10m ³/h, raw water tank 1-20m ³, pure water tank 2-40m ³;
Medium sized system: 20-50m ³/h, raw water tank 20-100m ³, pure water tank 40-200m ³;
Large scale system:>100m ³/h, multiple sets of equipment connected in parallel, water tank capacity configured at 1.5 times the water production capacity.
Targeted configuration of raw water quality
High hardness water (>500mg/L): After sand filtration, a softening device is added to prevent scaling of the RO membrane;
High organic matter water (COD>100mg/L): Ozone oxidation is added before the carbon filter to decompose large molecular organic matter;
Seawater/brackish water: RO pressure increased to 6-8 MPa, equipped with energy recovery device (such as PX pump).
Industry customized solutions
Pharmaceutical industry: The pure water tank is made of 316L stainless steel, with electrolytic polishing on the inner wall, which meets the requirements of GMP Appendix 1;
Electronics industry: RO water production is integrated with EDI to further remove ions and meet the demand for ultrapure water (resistivity ≥ 18M Ω· cm).
summarize
This water treatment system achieves deep purification and stable supply of water quality through the full process design of “storage filtration desalination storage”, and is suitable for industrial and civilian scenarios with high requirements for automation and water quality stability. Its core value lies in the efficient collaboration of multi-stage filtration and low operation and maintenance costs. Through water tank buffering and automatic control, it can flexibly adapt to fluctuations in raw water and water demand, making it a classic solution in the field of water treatment.