Sizing turns a duty into a specification. From your flow range, dose target and chemistry we fix the pump capacity and turndown, the day- and bulk-tank volumes, the line and injection sizes, and the materials of construction — the decisions that make a dosing system accurate, reliable and safe to run. This is how we size and select the equipment for a system we design and build.
Five inputs fix the whole specification.
Good sizing needs the duty envelope, not a single design point. We need the flow range (min–max), the dose range (from stoichiometry or jar test), the reagent and its strength, the back-pressure at the injection point, and the accuracy the consent demands. From those, every component falls out — and the spread between minimum and maximum duty sets the all-important turndown.
Capacity on peak duty, turndown on the full range.
Size pump capacity on the peak duty and check that the required turndown sits inside the pump's accurate range. Dilution buys turndown when the spread is too wide.
Day tank for control, bulk tank for delivery interval.
Storage is sized on consumption and delivery logistics, with safety margin and material compatibility.
Every wetted part rated for the reagent at working concentration and temperature.
| Reagent | Tank / pipe | Seals / diaphragm | Watch |
|---|---|---|---|
| Sulphuric acid | PP, PVDF, PE | PTFE, FKM | Dilution exotherm |
| Sodium hydroxide | PE, SS316 | EPDM, PTFE | Crystallisation when cold |
| Ferric chloride | GRP, PE, rubber-lined | EPDM, Hypalon | Very corrosive to steel |
| Sodium hypochlorite | PE, PVC | EPDM, Hypalon | Off-gassing → degassing head |
| Lime slurry | PE, lined steel | NR (hose pump) | Abrasive, settling, scaling |
| Polymer | PE, SS316 | low-shear (peristaltic/PC) | Shear damage |
Sized so the dose disperses and reacts where intended.
Injection and mixing geometry is sized on the mixing & injection page — get this wrong and even a perfectly sized pump under-performs.
Sized components feed the full process design and P&ID for the system we build.
Give us the flow range, dose target, reagent and injection pressure. We will size the pump and turndown, the storage, the lines, injection and mixing, and select compatible materials — then build it.
Our expertise spans multiple industries with sector-specific water treatment solutions.