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180F7000 Danfoss iSave 21 Energy Recovery Device

Type: iSave 21
Orientation: Horizontal
Including Electric Motor: Yes
Rated Flow: 350.0 l/min
Minimum Speed: 500 rpm
Maximum Speed: 1500 rpm
High Pressure Connections: 2" Victaulic
Low Pressure Connections: 2" Victaulic
Including Pressure Exchanger & Booster Pump: Yes
Housing Material (Excl. motor): Super Duplex Stainless Steel

Availability: See "Additional Information" below

Category Details

Danfoss has introduced two reverse osmosis energy recovery devices.

The iSave 21 with a brine flow of 7-21 m3/h and the iSave 40 with a brine flow of 22-40 m3/h are available now. More sizes are under development.

The Danfoss iSave consists of an isobaric pressure exchanger (PE), a high pressure positive displacement booster pump (BP) and an electric motor. 
The isobaric pressure exchangers are based on the technology used in the Danfoss APP pumps, and the high-pressure booster pumps are based on the vane pump principle enabling a very light and compact design. The design of iSave 21-40 ensures lubrication of the moving parts by the fluid itself. 
All parts included in the iSave 21-40 are designed to provide long service life with a constant high efficiency and minimum service required.
The vane pumps are fixed displacement pumps in which the flow is proportional to the number of revolutions of the driving shaft – enabling flow control.
The electric motor provides speed control of both the pressure exchanger and the high pressure booster pump on the same shaft – preventing over spin / over flushing.
The iSaves need a VFD that allows the motor to apply a constant torque from low speed to maximum speed.

Danfoss iSave 21

  • Flowrange: 7-21 m3/h (31-92 gpm)
  • Pressure: 10-82 bar (145-1,189 psi)
  • Efficiency: up to 93% (including high-pressure booster pump)
  • Length: 98.1 cm (38.6 inch)
  • Weight: 90 kg (198.4 lb)

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