Filtration covers a range of steps, from removing visible solids to separating dissolved salts. Picking the right level comes down to knowing what your water needs removed and how clean the result has to be. WesTech’s mobile filtration systems span that full range, so the goal is to match the method to the target and treat the water only as far as it needs.
Filtration Works Best After Clarification
Filtration polishes water that’s already had its bulk solids removed. When a stream carries heavy suspended solids, algae, or oil, clarification handles that load first, and filtration refines what remains. If your influent is already low in turbidity, you can start at the filtration step that matches your target. Either way, the cleaner the water reaching each filter, the longer that filter runs between cleanings.
Media and Pressure Filters: Solids and Targeted Metals
Granular media filters, including pressure filters, are the workhorses of the middle range. They capture suspended solids and reduce turbidity as water passes through a filter bed. With the right media and process, they also remove targeted metals. Aeration and oxidation ahead of the bed convert dissolved iron and manganese into particles the filter can catch, and similar approaches address metals such as arsenic. These filters suit drinking water pretreatment, cooling tower makeup, and process water that needs reliable solids and metals removal.
Disc Filters: Compact Solids Polishing
Disc filtration offers efficient liquid-solids separation in a small footprint and at low energy. It’s a strong choice when the priority is removing fine suspended solids from a large flow without a large filter house. On a mobile deployment, that compact footprint lets a capable polishing step fit on a single trailer.
Ultrafiltration: Fine Particulate and Pathogens
Ultrafiltration (UF) uses a membrane with pores around 0.01 micron, fine enough to remove particulate matter down to the scale of individual viruses. Because the membrane is a physical barrier, it produces consistent filtrate without depending on coagulant dosing. UF fits potable and process water duty, and it serves as pretreatment that protects downstream membranes from fouling.
Reverse Osmosis: Dissolved Solids and High Purity
Reverse osmosis (RO) reaches the finest level, separating dissolved salts and other total dissolved solids (TDS) that no particulate filter can catch. It’s the step for high-purity needs such as boiler feed water and low-TDS process water. RO usually follows ultrafiltration, which delivers the clean feed a reverse osmosis membrane needs to run efficiently.
Matching the Level to Your Target
The right level follows directly from the treatment goal:
- Suspended solids and turbidity call for media, pressure, or disc filtration
- Iron, manganese, or other targeted metals call for media or pressure filtration with the right pretreatment
- Fine particulate, pathogen-scale material, or membrane protection call for ultrafiltration
- Dissolved salts and high-purity water call for reverse osmosis
Many sites combine steps into a single train, filtering progressively finer until the water meets spec. A water analysis and a clear target tell you where to start and where to stop.
Start With the Water
The simplest way to choose is to work backward from the result you need. Define the effluent target, characterize the water, and the filtration level becomes clear. A mobile train can then be built to that specification, coarse where the solids are heavy and fine where purity is the goal, and deployed quickly to meet the need on site.
