Energy Recovery Devices

iSave 21 Plus / iSave 40

The iSave21 Plus and iSave40 are compact systems comprising an isobaric pressure exchanger, a high-pressure booster pump, and an electric motor. These systems prioritize longevity and efficiency, with all components designed to deliver consistent high efficiency while requiring minimal maintenance.The isobaric pressure exchangers draw on the technology used in Danfoss APP pumps, while the high-pressure booster pumps employ the vane pump principle, resulting in a lightweight and compact design.The vane pumps, which are fixed displacement pumps, enable flow control based on the revolutions of the driving shaft. Meanwhile, the electric motor facilitates speed control for both the pressure exchanger and the booster pump, effectively preventing overspin and overflushing.To operate the iSaves, VFD is necessary to enable the motor to apply a constant torque across a wide range of speeds. The accompanying sectional drawings visually illustrate the key components of the iSave21 Plus and iSave40

iSave 50-70

Energy Recovery Devices (ERD) are used in reverse osmosis (RO) systems to recycle the energy held in discharged brine from the membranes. This, iSave 50 and iSave 70 are designed for use with low viscosity and corrosive fluid such as sea water. The Danfoss iSave Energy Recovery Devices all consist of an isobaric pressure exchanger and a positive displacement pump combined into one compact unit. The high-pressure booster pump is based on the vane pump principle enabling a very light and compact design. The vane pumps are fixed displacement pumps in which the flow is proportional to the number of revolutions (rpm) of the driving shaft – enabling flow control. Speed control is made by a VFD. The iSave design ensures lubrication of the moving parts by the fluid itself. All parts included in the iSave 50 & 70 are designed to provide long service life with a constant high efficiency and minimum service required.