Overview
As innovative equipment in modern industrial filtration, multi-column automatic backwashing filters achieve an efficient operation mode of "non-stop filtration + online cleaning" through the collaborative design of multi-unit parallel structure and intelligent backwashing system. Their core advantage lies in breaking through the intermittent working bottleneck of traditional filters ("filtration-shutdown-cleaning"): by alternating backwashing of multiple filter columns, the system ensures 24/7 continuous operation, especially suitable for scenarios with strict continuity requirements in water treatment, chemical, food & beverage, etc. Compared with traditional single-column filters, this equipment improves maintenance efficiency by 80% and flow stability by 90%, becoming a key device to ensure fluid cleanliness in high-load production processes.
Core Working Principle and Structural Innovations
I. Multi-Column Parallel Operation Mechanism
The equipment typically consists of 3-8 filter columns in parallel, each (built-in) with cartridges (materials PP, stainless steel, or glass fiber). It realizes grouped backwashing via a PLC control system: when the pressure difference of a column reaches the set threshold (e.g., 0.2MPa), the system automatically switches it to backwashing, while the rest maintain normal filtration. During backwashing, high-pressure water (or gas) flushes reversely from the inner to outer side of the cartridge, combined with pulse vibration to remove impurities. Each backwashing takes only 1-3 minutes, with the entire system flow fluctuation ≤5%.
II. Intelligent Control and Fluid Optimization
1. Backwashing Trigger Logic:
- Pressure difference trigger: Monitored in real time by inlet/outlet pressure sensors, automatically starting backwashing when the pressure difference exceeds the preset value;
- Time trigger: Forced backwashing at set cycles (e.g., every 8 hours) to prevent microbial growth or viscous impurity deposition.
2. Fluid Distribution Technology:
Equipped with constant-pressure (diversion valve groups) to ensure balanced flow among columns (deviation ≤3%), avoiding single-column overload. The flow guide plate design reduces fluid turbulence, stabilizing filtration precision at 1-200μm.
Analysis of Typical Application Scenarios
1. Municipal and Industrial Water Treatment
In a circulating water system of an industrial park, multi-column filters (10μm precision) replaced traditional sand filters, with a treatment capacity of 500m³/h. Their automatic backwashing stabilizes turbidity below 1NTU without shutdown, reducing 3 maintenance personnel compared to traditional equipment. In seawater desalination pretreatment, 316L stainless steel columns resist chloride corrosion, extending the backwashing cycle to 72 hours and doubling the RO membrane life.
2. Chemical and Petroleum Refining
The quench oil filtration system of an ethylene plant uses multi-column filters (50μm stainless steel cartridges), removing polymer impurities through online backwashing and avoiding frequent replacements of traditional filters, saving ¥1.5 million annually in cartridge costs. For reaction liquids containing catalyst particles, their gradient filtration structure achieves a catalyst recovery rate of over 99%.
3. Food & Beverage and Pharmaceuticals
In the milk clarification process of a dairy factory, multi-column filters (0.45μm sterile-grade cartridges) enable continuous production. Combined with a CIP online cleaning system, they achieve a microbial interception rate >99.9% and filtrate turbidity <0.3NTU. A biopharmaceutical enterprise uses it to treat fermentation broth, recycling backwashing water to the pretreatment tank and reducing water consumption by 40%.
Performance Advantages and Industry Value
1. Continuous Operation and High-Efficiency Maintenance
The multi-column design breaks the "filtration-shutdown" cycle. For example, when handling 200m³/h flow, traditional single-column filters need 2 daily shutdowns for cleaning (30 minutes each), while multi-column systems operate 365 days non-stop, increasing production capacity by 12%.
2. Intelligence and Energy Saving
- Backwashing water consumption is only 1-3% of the treated water volume, 50% lower than traditional filters;
- Models integrated with IoT modules can remotely monitor pressure difference and flow data, providing 72-hour advance fault warnings and reducing unplanned shutdowns by 60%.
3. Flexible Adaptability and Long Life
Cartridge materials include PP, stainless steel, PVDF, etc., adapting to acid, alkali, and high-temperature media (e.g., 120℃ heat-conducting oil). 316L stainless steel columns have a service life of over 10 years, reducing replacement costs by 3 times compared to carbon steel equipment.
Selection and Maintenance Guidelines
I. Key Selection Factors
- Flow Matching: Configure at 1.2 times the maximum treatment flow. For example, select a 120m³/h model for a 100m³/h system, reserving flow redundancy for backwashing;
- Precision Grading: 5-50μm for pretreatment, 0.22-1μm for precision filtration (e.g., electronic-grade water), and 10-100μm for high-viscosity fluids (e.g., syrup);
- Material Selection: 316L stainless steel for chloride-containing media, FDA-certified PP for food-grade scenarios, and metal sintered cartridges for high-temperature oils.
II. Maintenance Optimization Strategies
1. Daily Inspection:
- Check the sealing of backwashing valve groups weekly to ensure no leakage;
- Analyze backwashing water quality monthly. If turbidity remains >10NTU, inspect cartridge damage.
2. In-Depth Maintenance:
- Perform integrity tests (e.g., bubble point tests) on cartridges quarterly;
- Replace solenoid valve diaphragms annually to prevent control failure due to aging.
Industry Development Trends
With the advancement of Industry 4.0, multi-column filters are developing toward intelligence and modularization:
- AI Predictive Maintenance: Analyzing pressure difference-flow curves via machine learning to predict cartridge life in advance, reducing maintenance costs by 30%;
- Nano-Coating Application: Superhydrophobic coatings on cartridges reduce pollutant adhesion by 50%, extending backwashing cycles to 1.5 times that of traditional cartridges;
- Integrated Design: Integrated with UV sterilization and activated carbon adsorption modules to form an "filtration-purification-disinfection" integrated system, suitable for municipal direct drinking water projects.
Conclusion
Multi-column automatic backwashing filters redefine industrial filtration efficiency standards through technological breakthroughs of "continuous operation + intelligent maintenance". From municipal water supply to high-end manufacturing, their multi-column parallel structure innovation and automatic control solve the efficiency bottleneck of traditional filtration in high-load scenarios. In the future, with the surging demand for high-purity fluids in semiconductors, hydrogen energy, and other fields, this equipment will further integrate intelligent monitoring and green material technologies, becoming core equipment to promote industrial process efficiency and low-carbonization.
