The core desalination technology of the platform: a semi-permeable membrane driven by pressure, with recovery, salt rejection, energy and concentrate all derived by real engines.
- Active
- Available
Energy Recovery Devices ERD
Devices that transfer pressure energy from the RO concentrate stream back into the feed, reducing specific energy consumption without changing the separation.
Overview
Devices that transfer pressure energy from the RO concentrate stream back into the feed, reducing specific energy consumption without changing the separation.
How it works
Separation mechanism and feed window. Applies wherever the concentrate leaves at meaningful pressure. Its benefit falls as recovery rises, because the concentrate flow shrinks.
What the process produces. Not applicable — an ERD changes no stream composition. It changes only the energy required to reach the same product.
Energy. It IS an energy technology: it reduces electrical demand by reusing pressure that would otherwise be throttled away.
Process sequence
Where this technology normally sits in a treatment train. The steps either side of it are documented in the Library as separate entries.
- RO concentrate
- Energy recovery device
- Feed / booster side
Typical applications
- Seawater RO plants where concentrate pressure is high
- BWRO plants with an interstage recycle
- Any RO train where concentrate throttling wastes recoverable head
Main equipment
- Pressure exchanger or turbine-type ERD
- Booster pump
- Controls and bypass
Key design parameters
The parameters an engineer actually sets, and why each one drives the design. EngiMetric does not assume any of them.
| Parameter | Why it matters |
|---|---|
| Concentrate flow and pressure | Sets the recoverable energy. |
| Transfer efficiency | Vendor-published; the whole saving depends on it. |
| Bypass and control strategy | Determines behaviour when the flow is off-design. |
Advantages
- Can cut RO specific energy consumption substantially.
- No effect on product quality or water balance.
Limitations
- Only recovers head that the concentrate actually still holds.
- Vendor-specific efficiency data; no generic figure is meaningful.
Engineering considerations
- EngiMetric compares specific energy with and without energy recovery in the RO feed-pressure tool; the efficiency used is the one you supply.
- An ERD never changes the mass balance — permeate and concentrate flows are identical with or without it.
Status and EngiMetric support
Industry maturity and commercial status describe the technology itself. EngiMetric support and quantitative modeling describe what this platform does with it — and those two are read from the engineering registry at build time, so they cannot drift from the code.
- Engineering maturity
- Mature How established the technology is in the industry. Not an EngiMetric claim.
- Commercial status
- Commercial Where the technology sits in the market. Not an EngiMetric claim.
- EngiMetric support
- Active No execution-registry entry exists, so no support is claimed.
- Design engine
- No Whether the Plant Designer can carry this as a configured process step.
- Quantitative modeling
- Partial No engine exists, so EngiMetric states no figure for this technology.
Related tools
Every tool below exists and is live. EngiMetric does not duplicate a formula here — the calculation lives in the tool, and this page links to it.
- RO Feed Pressure & Specific Energy Calculator Required feed pressure and specific energy with and without energy recovery.
- RO Energy & Specific Power Calculator Hydraulic and motor power for the pump duty.
Sources and references
- Transfer efficiency — Manufacturer datasheet; entered by the engineer, never assumed.
EngiMetric does not publish a bibliography of external literature for catalogued technologies. Where a figure is required, it is entered by the engineer from a datasheet or a published reference, and it is labelled as an input.