RO pre-engineering: permeate / recovery mass balance, TDS concentration, conservative recovery and an Envora UF–softening–antiscalant train. No membrane model, kWh/m³ or CAPEX.
Calculator
Qfeed = Qpermeate / recovery. Reject = feed − permeate. TDS, hardness and SDI add a mass balance, conservative recovery and Envora pretreatment notes.
Disclaimer: Calculations use general engineering relations and are for preliminary assessment only. They are not sufficient for design, quotation, equipment selection or investment decisions. Contact Envora Global for detailed hydraulic, chemical and process design.
RO sizing divides desired product (permeate) flow by recovery: feed = permeate / recovery, reject = feed − permeate. That first number sizes the high-pressure pump suction, pretreatment skid and concentrate line at feasibility level.
If TDS or conductivity is entered, a mass balance estimates permeate and concentrate salinity; the concentration factor 1/(1−Y) frames scaling risk. Hardness, silica, SDI and iron, when filled, trigger an Envora pretreatment order — UF, softening, iron removal and antiscalant dosing.
Two-pass assumes ~85% on pass 2 for boiler or high-purity duty; overall recovery is Y1×Y2. Flux and an 8″ 37 m² area give a rough element count. Osmotic pressure is a NaCl van’t Hoff order of magnitude only — vendor projection, kWh/m³, HP pump and CAPEX stay with Envora design.
Water-treatment engineers, EPC bid teams and investors who need rough RO capacity and pretreatment for process, potable, boiler, cooling or reuse trains.
Permeate (m³/h) is required. Default recovery is 70%; TDS, hardness or silica may suggest a more conservative default. Blank fields are ignored. Blank rejection = 98%, flux = 20 LMH, area = 37 m².
Mass balance; two-pass assumes 85% on pass 2. Osmotic pressure is a NaCl van’t Hoff sketch. kWh/m³, HP pump, membrane model, CIP and CAPEX are out of scope. Final design is an Envora projection.
Recovery typically falls as feed TDS, hardness and silica rise (about 50–75%). Scaling indices, SDI and antiscalant dose are finalized from site data. The tool may suggest a lower default from those inputs.
No. It returns flows, a TDS estimate, a rough osmotic order of magnitude and a sketch element count. Exact kWh/m³, HP pump, membrane model and CAPEX come from vendor projection and Envora hydraulics.
High SDI or turbidity calls for Envora UF (potable / seawater trains) to protect membranes. Hardness and silica drive antiscalant and ion-exchange softening. Iron must be removed before RO. The water-analysis tool screens the full ion set.
Discharge, evaporation or further recovery (second pass / ZLD) is a separate study. The recovery-savings tool shows annual volume and tariff impact.
Boiler feed and low-conductivity process water often need a second pass; the tool warns if single-pass permeate is still high. EDI / ion exchange is added after RO in Envora design.
Envora Global’s engineering team prepares a project-specific pre-assessment covering water characterization, P&IDs, equipment lists, OPEX/CAPEX and turnkey delivery.
