Treat the ionic profile, not one conductivity number
High total dissolved solids describes a concentration, but process selection depends on which ions are present, how they vary and what finished-water composition is permitted and intended.
Direct answer
Obtain a charge-balanced ionic analysis with representative ranges, temperature, pH and supporting scaling and fouling indicators. Define the intended product-water specification and jurisdiction-specific product category before deciding how much dissolved material should be removed or retained. A membrane route may be appropriate, but its pretreatment, pressure, recovery, energy, cleaning and concentrate duties must be calculated from the actual feed. Product conditioning or controlled blending may also require review, monitoring and legal confirmation. Compare proposals on net compliant product water, complete mass balance, operating limits and residual management rather than a generic salt-rejection percentage.
System focus 01
Conductivity or TDS alone cannot show whether calcium carbonate, sulfate, silica or another constituent will constrain recovery, nor does it establish taste or legal product composition. Request major cations and anions, alkalinity, hardness, silica, relevant trace constituents, pH and temperature on representative samples. Check the ionic balance and laboratory units before using the data in a design model. Then state the desired product-water range, treatment claims and destination markets for qualified review. Keep naturally derived constituents, intentionally added minerals and blended streams traceable rather than using an undefined final TDS target.
System focus 02
High dissolved solids can increase scaling potential, but the required pretreatment depends on the ionic combination, concentration factor and membrane selection. Suspended solids, organics, iron, manganese, oxidants and biological activity may create separate risks. Ask the process designer to show the purpose and limits of filtration, softening, dosing, pH adjustment or other proposed stages. Chemical selection should include compatibility, storage, dosing control, safe handling and residual implications. A generic cartridge filter does not replace a complete pretreatment assessment, and an antiscalant name does not prove that every recovery scenario is acceptable.
System focus 03
Request the selected membrane type, array, design flux, permeate and concentrate flows, recovery, predicted pressure, temperature basis and product quality over the agreed feed range. Predictions are engineering models whose assumptions should remain attached to the quotation. Review pump, energy-recovery or staging concepts where relevant, plus flush, preservation and cleaning provisions. The declared product flow should be measured at a named point and should not conceal internal recycle or auxiliary use. Consider how membrane aging, cleaning and feed variation are managed operationally without turning a conservative allowance into an unsupported lifetime guarantee.
System focus 04
Very low-mineral permeate may require project-specific conditioning for the intended product, equipment compatibility or sensory objective. Options can include controlled blending or addition through a validated process, but the permitted approach and final description must be reviewed locally. Specify ingredient or blend-water identity, dosing control, interlocks, monitoring and traceability. The final water then enters a hygienic storage and filler-feed system with defined turnover and cleaning. Conductivity can support control but may not uniquely identify every constituent, so the release plan should retain appropriate laboratory checks and controlled formulations.
System focus 05
A high-TDS feed produces a more concentrated residual stream whose volume and composition follow the complete mass balance. Identify possible discharge, reuse or further-treatment routes only after site water demand, materials, soil or sewer constraints and local permission are reviewed. Reuse in cooling, cleaning or another service can transfer salts or chemicals into equipment and wastewater, so compatibility and accumulation need evaluation. Acceptance should record feed composition, temperature, flows, pressures, conductivity and relevant product results after stabilization. Ongoing trends should trigger investigation before operation moves outside the declared design envelope.
High-TDS proposal matrix
Require each supplier to state the feed case, net product result and residual boundary behind the proposed equipment.
| Decision area | Confirmed input | Supplier return | Review question |
|---|---|---|---|
| Feed chemistry | Ionic analysis, ranges and temperature | Design envelope and missing-data list | Are scaling species and variation represented? |
| Product objective | Composition, category and destination review | Permeate and conditioning basis | Is the final water, not only membrane output, defined? |
| Pretreatment | Fouling risks and site chemical constraints | Stage purpose, dose and monitoring | Does each stage address a documented mechanism? |
| Membrane duty | Net demand and operating schedule | Array, recovery, pressure, flows and utilities | Are assumptions and recycle streams visible? |
| Residual route | Site services and local review boundary | Concentrate quantity, quality and tie-in | Can the proposed route receive this stream? |
| Acceptance | Sampling and instrument requirements | Test method, stabilization and records | Will evidence reflect the declared feed condition? |
Treatment and product decisions remain conditional on confirmed chemistry, local requirements, selected equipment and the approved residual-management route.
Buyer questions
Use these answers as a project-planning starting point. Final equipment and performance remain subject to the confirmed brief.
There is no universal threshold. The ionic composition, product target, local category rules, sensory objective, treatment alternatives, residual route and economics all matter. Use a complete analysis and project-specific process review.
No. Actual permeate depends on feed composition, temperature, pressure, recovery, membrane condition and the complete process. Product conditioning, storage and sampling also affect the finished-water evidence.
Potential uses require a site-specific water-quality, material, health, wastewater and regulatory review. Reuse can concentrate salts or treatment chemicals elsewhere, so it should not be assumed from flow volume alone.
Conductivity is a useful trend and control signal, but different ionic mixtures can produce similar readings. Laboratory analysis remains necessary where individual constituents, source changes or product specifications must be confirmed.
Capacities, process routes, layouts, utilities and equipment shown on this site are decision frameworks and reference examples. They are not a final specification, performance guarantee or offer. Confirmed scope and performance are defined in the signed technical and commercial agreement.
Allot Tech project desk
Share the source water, bottle, target output, pack format, factory status and destination. We will use them as the basis for a project-specific configuration discussion.