Applications
(For water treatment UV equipment, applicable to both low-pressure and medium-pressure UV systems, practical technical guidelines)
Core principle of UV disinfection: Microorganisms need to receive sufficient effective UV dose (Dose = UV Intensity × Exposure Time). All optimizations focus on increasing effective UV dose.
1. Optimization of Hydraulic Conditions (Highest Priority)
Control flow velocity to ensure water residence time
Excessively high flow velocity leads to insufficient exposure time and inadequate UV dose. Long-term operation above rated flow is prohibited.
Recommendation: Actual operating flow ≤ nominal treatment flow of the equipment.
Optimize reactor structure to avoid water flow short-circuiting
Short-circuiting allows partial water to pass through rapidly without adequate irradiation. Install baffles and flow deflectors to ensure uniform water distribution around UV lamps.
Maintain full pipe flow
Air pockets and liquid level fluctuations inside the reactor must be eliminated. Air bubbles block UV radiation and cause light shielding effect.
2. Water Pre-treatment (Turbidity is the Primary Influencing Factor)
Suspended solids, colloids and color absorb and scatter UV light, greatly reducing UV transmittance (UVT).
Inlet turbidity control: NTU ≤ 5; strict applications require NTU ≤ 1.
Install pre-filtration devices: bag filters, precision filters, quartz sand filters.
Reduce water color, iron and manganese ions. Metal ions scale on quartz sleeves and block UV rays.
Key point: Higher UV transmittance (UVT) brings significantly better disinfection performance. Enhanced pre-treatment is mandatory for opaque liquids.
3. Optimization of Lamps and Optical System
Regular cleaning of quartz sleeves
Mineral deposits and biofilm formed in water adhere to sleeves and block UV transmission.
Adopt online cleaning or offline acid cleaning for low/medium-pressure UV systems periodically.
Use well-matched UV lamps and ballasts
Parameter mismatch is forbidden. Lamp aging causes UV output decay; replace lamps once reaching service life.
Proper lamp selection
Clear water with high UVT: low-pressure UV lamps with high energy efficiency.
High-turbidity water or hard-to-inactivate microorganisms: medium-pressure UV lamps with broad-spectrum wavelengths and stronger penetration.
Ensure quartz sleeves are intact without cracks or abrasion.
4. Electrical Control & Operation Strategy
Stable power supply for ballasts. Voltage fluctuation results in reduced UV output.
Avoid frequent start-stop cycles: repeated startup accelerates lamp light decay.
Thermal insulation under low ambient temperature: low temperature weakens UV radiation of low-pressure lamps.
5. Auxiliary Process Solutions
Increase lamp power density
Deploy reasonable quantity of lamps within the reactor. Blind power increase is not allowed; lamp power must match reactor dimension.
Series connection of multiple units
If single unit cannot deliver required UV dose, connect two or more UV sterilizers in series to accumulate UV dosage.
Control water temperature: extreme high or low temperature impairs microorganism inactivation and lamp performance.
6. Routine Maintenance for Long-term Stable Efficiency
Regular inspection: Monitor readings of UV intensity sensors. Clean sleeves immediately once intensity drops.
Replace expired lamps on schedule. Visible light emission does not equal effective UV output.
Regular venting to remove air bubbles inside the reactor.
Concise Summary (Directly applicable for technical proposals)
Five core measures to improve disinfection efficiency:
① Stabilize flow rate and extend effective water exposure time;
② Apply pre-filtration to raise water UV transmittance (UVT);
③ Clean quartz sleeves regularly to eliminate light-blocking scaling;
④ Ensure matching parameters between lamps and ballasts, replace aged lamps timely;
⑤ Optimize flow channels to eliminate flow short-circuit and air bubble interference.
