A seawater RO skid is one part of a water-supply project. For an island, coastal hotel or remote facility, the enquiry should connect intake conditions with useful water at the point of demand. Define the responsibilities between packages early so missing interfaces do not emerge during installation.
1. Describe the intake and the demand profile
Provide the proposed intake location and arrangement, the available water analysis and the observed temperature range. Mark sampling dates and distinguish measurements from assumptions. Ask the site team about seasonal changes, storms and periods when the intake cannot operate. These observations belong in the enquiry even when a full intake study is not yet available.
Build a demand schedule that separates everyday use from peak occupancy, tank filling and other intermittent loads. State available power hours and required storage reserve. Identify who will confirm the intake design and who owns pretreatment. Ask the equipment supplier to list the inlet conditions that its proposal assumes.
2. Define useful-water quality and the concentrate route
Specify the intended use of product water and where its quality will be verified. Ask the responsible engineer to define any finishing treatment, storage and distribution requirements. Keep these items visible in the supply boundary: water leaving the RO skid and water delivered to a consumer are different verification points. Do not treat an equipment brochure as evidence that a complete site supply meets its intended use.
Concentrate carries constituents separated from the feed water, as described in Bureau of Reclamation research. Request its proposed flow and composition basis. Identify a responsible party for assessing the discharge route and local project requirements. The supplier's water balance should distinguish normal concentrate from cleaning effluent and pretreatment waste; they need not share the same handling route.
3. Compare energy, availability and handover on equal terms
When comparing an energy figure, ask which equipment is included and what feed conditions, recovery and operating point it represents. Record whether intake pumping, pretreatment and product-water distribution sit inside or outside that number. Request the assumptions in writing instead of ranking proposals by an isolated kWh/m³ value.
List maintenance access, corrosion exposure, consumable deliveries and the skills available on site. Ask how stored water or another supply covers planned downtime. Before purchase, request layout and interface drawings, electrical loads, control descriptions, spare-parts recommendations and a commissioning plan. Agree the flow and quality measurements, test conditions, training and handover records used for acceptance. The worksheet below creates a common starting point for that discussion.
Data to collect before comparing proposals
| Parameter / interface | Unit / format | Why it matters |
|---|---|---|
| Seawater analysis / salinity | Laboratory report; g/L or mg/L | Provide units, sample location, date and seasonal observations. |
| Temperature / intake availability | °C; hours and interruptions | State expected operating conditions and known access constraints. |
| Useful-water demand / storage | m³/day; m³ | Separate average demand, peaks and reserve storage. |
| Product-water use and target | Defined quality and test point | Identify finishing, storage and distribution responsibilities. |
| Concentrate / other waste streams | m³/h; proposed handling route | Identify who confirms the route and project requirements. |
| Energy comparison boundary | kWh/m³; included equipment | Ask for conditions and all equipment included in the figure. |
| Service and acceptance | Access plan; test protocol | Agree maintenance logistics, operator training and handover evidence. |
Technical references
- Bureau of Reclamation — Desalination concentrate research ↗
- BOKAWATER — Portable desalination machine ↗
Prepared with AI assistance from the references below and original project-planning checklists. General engineering guidance; project specifications require confirmation by the responsible engineer.