Energy recovery devices for reverse osmosis applications

3-in-1 energy recovery device

The 3-in-1 Energy Recovery Device (ERD) optimized for sea water reverse osmosis applications. With iSave you get pressure exchanger, booster pump and motor integrated into one compact unit for high efficiency and short pay-back time.

The small footprint of iSave makes it a popular solution when the space is limited. When fitted with iSave, the Danfoss APP pumps produce more fresh water per square meter than any other system in the market.

iSave can be used in almost any SWRO application – land-based or marine, new or retrofit. The 3-in-1 design allows fast commissioning, continuous monitoring of performance and easy regulation to accommodate seasonal changes. Other isobaric devices have been known to cause over-spin and over-flushing that lead to poor process control and low efficiency. This is avoided with the active control possibilities offered by the iSave technology.

iSave captures hydraulic energy from the high pressure reject stream of the SWRO process and transfers the energy back into the system, drastically reducing the energy consumption regardless of flow rate and size of your SWRO system. Besides substantial energy savings, the iSave ERD also cuts capital expenditure by reducing high-pressure pump size, number of pipes and components thanks to its integrated design.

Superior energy recovery in SWRO

Danfoss iSave is a patented, high-efficiency Energy Recovery Device (ERD) that guarantees constant membrane feed in SWRO applications of any size – on land, at sea or on the move.

Features and benefits

Extensive application know-how
Competitive efficiency rates
Compact – pressure exchanger, pump and motor in one unit
Easy and service-friendly design
Simple and reliable with high uptime
Short pay-back time

Product range

iSave 21 Plus

iSave 21 Plus is a powerful ERD for smaller plants with a water capacity of 110 to 350 m3 per day. iSave 21 Plus is designed for high reliability, low maintenance and reduced lifecycle costs.

iSave 40

The iSave 40 consists of an isobaric pressure exchanger, a high-pressure positive displacement booster pump and an electric motor. Max. differential pressure: 5 barg/72 psig. Speed: 600 – 1200 rpm.

iSave 50

iSave 50 is designed for use with low viscosity and corrosive fluid such as sea water. Max. differential pressure: 5 barg/ 72 psig. Speed: 525-650 rpm

iSave 70

iSave 70 is designed for use with low viscosity and corrosive fluid such as sea water. Max. differential pressure: 5 barg/ 72 psig. Speed: 625-875 rpm.

Related products

APP pumps

The APP pumps are designed for SWRO in land-based and marine applications, offering the highest efficiency rates in the industry. The compact design, long service intervals and reliability of the APP makes it a first choice for small and medium-sized desalination plants

APP S 674 pumps

The APP S 674 pumps are designed for SWRO offshore applications, offering the highest efficiency rates in the industry – comes with API 674 and ATEX certification.

STEMAN Sensors s.r.o.

Hradní 27/37
710 00 Ostrava 10
IČO: 03674690
DIČ: CZ03674690

+420 596 220 199
+420 702 165 774