Inactivate bacteria, viruses, and protozoa using ultraviolet light without adding chemicals, generating disinfection byproducts, or affecting water chemistry.
UV disinfection uses germicidal ultraviolet light (primarily 254 nm wavelength) to damage the DNA and RNA of microorganisms, rendering them unable to reproduce. Unlike chlorine, UV does not add chemicals to water, does not create harmful disinfection byproducts (THMs, HAAs), and does not affect taste or odour. It is ideal for wastewater discharge, water reuse, and as a final barrier in multi-barrier treatment systems. UV dose is measured in mJ/cm2 – typical wastewater requires 20-40 mJ/cm2 for 4-log reduction.
No chlorine, no byproducts, no residual chemicals. Purely physical disinfection process.
Effective against bacteria, viruses, Giardia, Cryptosporidium – chlorine-resistant cysts are easily inactivated.
Disinfection occurs within seconds of exposure. No contact tank required unlike chlorine.
Online UV intensity sensors confirm dose delivery. Failed lamps trigger immediate alarm.
Step-by-step breakdown of the treatment process from influent to effluent.
Suspended solids reduce UV effectiveness. 10-50 µm pre-filtration ensures target transmittance >65% UVT.
Low-pressure (monochromatic 254 nm) or medium-pressure (polychromatic 200-300 nm) lamps selected based on target organisms.
CFD-modelled reactor geometry ensures all flow receives required dose. Baffles eliminate short-circuiting.
Water flows past quartz-sleeved UV lamps. Dose calculated as UV intensity (mW/cm2) – residence time (s) = mJ/cm2.
Online UV intensity monitors measure actual dose. Automatic sleeve wiping or chemical CIP prevents fouling.
Explore the equipment components that make this process effective.
SS316L reactor with quartz sleeves, UV lamps, intensity sensors.
Cartridge or bag filter ensuring UVT >65% for effective UV transmission.
Online sensor measuring actual UV intensity for dose verification.
Automatic mechanical or chemical cleaning of quartz sleeves.
Final disinfection before river or sea discharge meeting bacterial standards.
Disinfect treated water before reuse for irrigation, cooling, or process washing.
Primary or secondary disinfection for potable water without chlorine taste.
Reduce combined chlorine and provide supplemental disinfection.
This treatment stage is engineered to achieve specific contaminant removal targets while providing stable, predictable performance across variable inlet conditions. Design parameters are calculated from wastewater characterisation data, regulatory requirements, and site-specific constraints including footprint, energy availability, and operator capability.
Design validated by CFD modelling and pilot testing to confirm performance guarantees.
Equipment selected for 20-year design life with minimal wearing parts and easy access.
Automated dosing and feedback control minimise reagent consumption and sludge production.
Online monitoring and data logging demonstrate continuous consent compliance.
| Design Flow | 10 – 5,000 m³/h (application specific) |
| Inlet Variability | Designed for 1:3 peak-to-average flow ratio |
| Removal Efficiency | 85 – 99% depending on target contaminant |
| Hydraulic Retention | Calculated from kinetic constants and safety factors |
| Power Consumption | 0.5 – 5.0 kWh/100 m³ (process dependent) |
| Chemical Dose | Auto-controlled based on online analysers |
| Sludge Production | 0.2 – 1.5 kg DS/kg contaminant removed |
| Materials | SS304, SS316L, or carbon steel with coating |
No treatment stage operates in isolation. This process is designed to receive conditioned influent from upstream stages and deliver effluent quality suitable for downstream processes. Hydraulic and organic loading rates are balanced across the complete treatment train to prevent bottlenecking and ensure overall plant efficiency. Our engineers model the complete flowsheet to optimise Capital expenditure and Operating expenditure across the plant lifecycle.
Screening, equalisation, and pre-treatment protect this stage from damage and overload.
Effluent quality ensures downstream biology, filtration, or disinfection performs optimally.
Reject streams, filtrate, and centrate are routed back to appropriate upstream points.
Our engineers design and commission complete treatment systems including all equipment, automation, and commissioning support.
Our expertise spans multiple industries with sector-specific water treatment solutions.