Engineering guide
How We Size a UV or Ozone Water Treatment System
Equipment capacity is the result of the treatment duty—not the starting point. Puritor begins with the water, flow, target and operating conditions, then selects UV, ozone or an integrated treatment train.
Sizing inputs by technology
Different processes require different design information
The fields below define the first engineering review. Missing information does not stop the discussion; it identifies what should be tested or confirmed next.
UV Disinfection
UV systems are selected around delivered UV dose at the design flow and the actual transmission characteristics of the water.
- Normal and peak flow rate
- UV transmittance (UVT) or water clarity
- Required UV dose or microbial target
- Suspended solids, iron, hardness and fouling risk
- Pressure, chamber orientation and connection size
- Monitoring, cleaning and control requirements
Ozone Treatment
Ozone output alone is not a design basis. Dose, mass transfer, contact time and ozone demand determine the useful treatment capacity.
- Flow and operating schedule
- Water analysis and ozone demand
- Oxidation or disinfection objective
- Target applied dose and residual, if known
- Feed gas, ozone concentration and cooling
- Injection, contact and off-gas arrangement
Integrated Treatment
Combined trains separate the oxidation duty from final polishing or disinfection and coordinate the interfaces between each process.
- Upstream filtration or pretreatment
- Contaminants and target results by stage
- Ozone contact and downstream removal
- Activated carbon or other polishing steps
- Final UV disinfection requirement
- Instrumentation, interlocks and control philosophy
Process selection
The water problem determines the treatment route
These are typical starting points, not automatic prescriptions. Final selection depends on water analysis, performance targets and operating constraints.
Clear water + microbial target
Good UV transmission, controlled solids and a requirement for final microbial inactivation.
Typical starting point: UV
Color, odor or oxidizable compounds
The process needs oxidation, contact time and managed gas-to-water transfer before final polishing or discharge.
Typical starting point: Ozone
Multiple contaminants + final disinfection
Oxidation and downstream removal are followed by a separate disinfection barrier.
Typical starting point: Integrated train
Reference process logic
A treatment train, not a collection of unrelated machines
One common integrated concept is shown below. Each step is included only when the water analysis and treatment objective justify it.
Alternative trains may omit, reorder or add stages. Hydraulic conditions, by-products, residual management and the final water use must be reviewed before configuration.
Supporting equipment
Components are selected with the core process
Supporting equipment is specified to make the treatment system operable, measurable and safe. It does not replace the core process selection.
Oxygen Supply & Flow Control
Oxygen concentrators, PSA units, flow measurement and regulation for the required ozone concentration.
Injection & Contact
Venturi injection, static mixing and contact arrangements matched to pressure, flow and dose.
Dissolved Ozone & ORP
Water-side monitoring for residual verification, process control and commissioning.
Ozone Destruction
Managed off-gas collection and destruction where the contact system and site conditions require it.
What to send
A useful first project brief
Send what is already available. Puritor can identify the missing design inputs before recommending equipment.
What Puritor returns
Engineering output for the next decision
Start with the water—not a generator capacity
Send the flow, water source, available analysis and treatment objective. We will identify the appropriate process and the next engineering step.
