Sand Filter, Carbon Filter, Fully Automatic Reverse Osmosis Precision Water Filtration Mechanical Equipment

Product description

This device is an integrated deep water purification system that uses a combination process of “pretreatment (sand filtration+carbon filtration)+reverse osmosis precision filtration” to convert raw water (such as tap water and groundwater) into high-purity water. It is widely used in industrial production, commercial services, and residential water purification fields. The following will explain the system composition, working principle, core advantages, and application scenarios:
1、 Core components and functions of the system
1. Sand Filter
Construction: Pressure bearing filter tank (mostly made of fiberglass and stainless steel), filled with quartz sand of different particle sizes (upper coarse sand, lower fine sand, forming a gradient filter layer), equipped with an automatic backwash device (electric valve+controller).
Core functions:
Physically intercepting suspended solids (SS) in raw water, such as sediment, rust, algae, colloidal particles, etc;
Reduce the turbidity of water (from 10-30NTU to below 1NTU) to alleviate the load for subsequent filtration;
Automatic backwashing: When the pressure difference of the filter layer is greater than 0.05MPa or timed (8-12 hours), the system automatically starts backwashing to restore the filtering capacity of the filter material.
2. Carbon Filter
Construction: The filter tank is filled with granular activated carbon (preferably coconut shell carbon, with a specific surface area of ≥ 1000m ²/g), which is controlled in conjunction with the sand filter.
Core functions:
Adsorption of organic matter (such as pesticide residues, industrial solvents, humic acid), odors, and pigments in water;
Efficient removal of residual chlorine (Cl ₂, HClO, etc. in tap water) to prevent oxidation and damage to the reverse osmosis membrane (membrane elements typically have a tolerance of less than 0.1mg/L to residual chlorine);
Assist in removing some heavy metal ions (such as lead and mercury) and volatile organic compounds (VOCs).
3. Precision Filter (Security Filter, Fine Filter)
Construction: A small filter made of stainless steel or PVC material, with a built-in 5 μ m PP melt blown filter element or folded filter element (as a “pre protection” for the reverse osmosis system).
Core functions:
Retain residual small particles (such as activated carbon powder and sand particles) after pre-treatment, ensuring that the particle diameter entering the reverse osmosis membrane is ≤ 5 μ m;
Prevent impurities from scratching the surface of the membrane or blocking the membrane pores, and extend the service life of the reverse osmosis membrane.
4. Fully automatic reverse osmosis device (RO System)
Core components:
High pressure pump (providing working pressure of 1.0-1.5MPa, made of 316 stainless steel, corrosion-resistant);
Reverse osmosis membrane module (roll type composite membrane, such as Dow BW30-4040, desalination rate ≥ 99.5%);
PLC control system (integrated touch screen, pressure sensor, conductivity meter, liquid level switch);
Automatic valve group (controlling the discharge and flushing process of water inlet, water production, concentrated water).
Core functions:
Utilizing the selective permeability of reverse osmosis membranes (allowing only water molecules to pass through, intercepting over 99% of salt, bacteria, viruses, and large molecular substances);

Fully automatic operation: supports one click start, low-pressure flushing (automatic flushing of membrane surface during startup/shutdown), water quality monitoring (automatic discharge of excess water conductivity), and fault alarms (such as high-pressure overload and membrane fouling);
Produce pure water (conductivity usually ≤ 50 μ S/cm, depending on the quality of the raw water).
2、 System workflow
Raw water pretreatment:
The raw water first enters the sand filter to remove large suspended particles and colloids, reducing turbidity; The effluent enters the carbon filter to adsorb organic matter, residual chlorine, and odors; Subsequently, fine impurities are intercepted through a precision filter to ensure that the water quality meets the inlet requirements of the reverse osmosis membrane (SDI ≤ 5, turbidity ≤ 1NTU).
Reverse osmosis deep purification:
The pre treated water is pressurized by a high-pressure pump to the working pressure of the reverse osmosis membrane and enters the membrane module:
Water molecules permeate through the membrane to form pure water, which enters the pure water tank or is directly transported to the water consumption point;
Salt and impurities are intercepted to form concentrated water (the discharge ratio is controlled by valves, and the recovery rate is usually 60% -75%).
Intelligent control and maintenance:
The PLC system monitors real-time parameters such as pressure, flow rate, and water conductivity, and automatically adjusts the operating status (such as concentration ratio and flushing frequency); When the membrane is contaminated (pressure difference increases) or the water quality does not meet the standard, it will automatically alarm and prompt maintenance, achieving unmanned operation.
3、 Core advantages
High purification efficiency: Sand filtration+carbon filtration pretreatment can remove more than 80% of suspended solids and organic matter, reverse osmosis membrane deep desalination, total desalination rate ≥ 95%, and stable water quality of the produced water;
High degree of automation: from pre-treatment backwashing to reverse osmosis operation and flushing, the entire process is automatically controlled, reducing manual operations and minimizing human errors;
Adequate membrane protection: Multi stage filtration (sand filtration → carbon filtration → precision filtration) provides “triple protection” for reverse osmosis membranes, extending their service life to 2-3 years (traditional systems typically take 1-2 years);
Strong adaptability: It can handle raw water of different qualities (such as high turbidity groundwater and chlorine containing tap water), and adapt to water quality fluctuations by adjusting parameters (such as pressure and recovery rate).
4、 Typical application scenarios
Industrial sector:
Small electronic factory (component cleaning water, conductivity ≤ 10 μ S/cm);
Food and beverage factory (ingredient water, in compliance with GB 19298-2014 “Packaging Drinking Water” standard);
Laboratory (analytical water, meeting the requirements of Class III water).
Business field:
Hotel/office building (direct drinking water system, produced water can be consumed directly);
Car wash shop (high-purity cleaning water to reduce residual body scale).
Civilian field:
Rural centralized water supply (treating high turbidity well water to improve drinking water safety);
Villa whole house water purification (replacing traditional water purifiers and providing whole house pure water).
summarize
This device achieves efficient conversion from raw water to pure water through the collaborative design of “pretreatment+reverse osmosis”, combining purification depth, automation level, and operational stability, making it an ideal choice for small and medium-sized water use scenarios. If higher purity water is required (such as medical injection water), a secondary reverse osmosis or EDI (Electrodeionization) system can be added on this basis to further reduce the conductivity to below 0.1 μ S/cm.