Submit a representative dissolved-constituent analysis
Provide salinity and individual constituents relevant to the membrane review, together with temperature, oil, solids and upstream chemicals. Include analytical uncertainty and changes between operating cases. A single total-dissolved-solids value can conceal important scaling or compatibility issues. Ask the supplier to identify required additional testing before it commits to a membrane arrangement, rather than filling missing chemistry with assumptions that are not visible in the equipment offer.
Define the product-water requirement explicitly
Obtain the quality and quantity required by the receiving process, including any blending or polishing boundary. Ask which constituents the selected arrangement is expected to control and what remains outside its scope. Freshwater quality is not one universal specification. A water suitable for one reuse destination may not meet the requirements of another, so the supplier response should reference the actual project criteria and accepted analytical methods.
Review pretreatment and protection assumptions
Identify the feed condition accepted by the membranes and the upstream separation, filtration and conditioning needed to achieve it. Request the supporting scope and operating assumptions. If pretreatment is excluded, assign responsibility for demonstrating the accepted membrane-feed condition. Do not compare a bare membrane package with a complete treatment train as equivalent equipment, and do not assume that removing visible oil alone makes every produced-water stream suitable for membrane desalination.
Examine recovery and concentrate together
Ask for a feed, product and concentrate balance for the accepted chemistry and temperature. Review how scaling risks, pressure requirements and operating limits affect the proposed recovery. Identify where concentrate can go and which handling costs remain outside the equipment offer. A higher recovery figure is not automatically preferable if it depends on unsupported assumptions or creates a residual stream that the site cannot accept or manage.
Agree evidence, cleaning and replacement scope
Request the calculation basis, representative trials where needed and the limits of performance evidence. Identify cleaning equipment, chemicals, membrane references, operating documents and acceptance responsibilities. State how changes in feed chemistry will be reviewed after purchase. Keep replacement pricing and projected membrane life separate from contractual performance commitments, and ask for the conditions behind any estimate rather than treating it as a guarantee for all future operating cases.
Use a feasibility gate before a firm equipment comparison
Ask each supplier to identify accepted chemistry, missing inputs and the reason its proposed train is technically supported. Separate feasibility work from final configuration approval and agree what evidence closes each uncertainty. Compare net product-water output, concentrate handling and complete pretreatment at the same boundary. Where the feed is unsuitable for the proposed membrane route, review alternative treatment or reuse destinations instead of accepting a standard RO skid solely because its nominal capacity matches the desired water rate.
Put these items side by side in the bid review
| Purchase item | Question to resolve | Evidence to request |
|---|---|---|
| Chemistry | Are scaling constituents and variation reviewed? | Accepted analytical basis |
| Recovery | What concentrate is produced? | Complete water and solute balance |
| Scope | Who establishes membrane-feed quality? | Pretreatment responsibility register |
Suggested wording for the quotation request
Please review reverse-osmosis feasibility for the attached produced-water analyses and product-water requirements. Identify missing chemistry, accepted feed limits, pretreatment, membrane configuration and recovery assumptions. Provide product and concentrate balances, utilities, cleaning scope and disposal interfaces. State the evidence required for configuration approval and site acceptance, replacement membrane references and commercial exclusions. Distinguish preliminary calculations from performance commitments for the ordered treatment train.
Compare the complete treatment duty rather than one advertised removal percentage. Keep representative water analyses, flow variation, required outlet quality and residual destinations together in the purchase specification. Identify what each proposed stage removes and what remains in the treated water, recovered oil and waste streams. Agree utility assumptions, operating responsibilities and configuration-specific evidence before ordering. Installation, chemical handling, sampling and maintenance must follow the accepted project design, supplier instructions and approved site procedures. Equipment selection does not itself authorize discharge, reuse or disposal.
For the wider equipment scope, consult the Produced Water Treatment: Oil Removal vs Salt Removal. Use the RFQ checklist to collect the supporting documents before requesting a configuration-specific quotation.
Buyer questions
Is total salinity enough to specify a produced-water RO plant?
No. Individual constituents, oil, solids, temperature, chemical carryover and variation also need review.
Should the highest proposed recovery win the bid?
Not automatically. Assess technical limits, net product quality, energy, cleaning and the management of the resulting concentrate.
Background and supplier contact
Produced-water desalination design research offers related background, not certification of the equipment in a quotation. Applicability must be checked for the project and destination.
Explore the oilfield wastewater treatment system, browse all technical resources, or visit Vance Petroleum for company information. Request a treatment proposal with the water analysis, treatment flow and required outlet quality.