Hydro-ejectors (POLYVAC)

Hydro-ejectors are ejectors where the driving fluid is a liquid (generally water).
They enable :

achieve a vacuum level close to the vapour pressure of the motive medium,
withstand very high counter-pressures,
combine several functions in a single unit: vacuum, compression, condensation and gas cleaning.

Thanks to these characteristics, LVI SYSTEMS has developed the POLYVAC range of universal vacuum units adapted to the most demanding industrial environments:

POLYVAC H Series: ATEX pollution-proof version, ideal for hazardous areas.
POLYVAC V Series: anti-corrosion & anti-pollution version, designed for corrosive gases and aggressive solvents.

By combining them with steam ejectors, it is possible to go down to 1 mbar abs and draw in large gas flows.

Details Hydro-ejectors (POLYVAC)

The advantages of our hydro-ejectors:
- Reliable operation (static equipment in contact with the process).
- Capable of extracting dust-laden, corrosive or toxic gases and high-temperature liquids.
- Scrubbing malodorous or dangerous gases with an appropriate engine fluid.
- Can be operated with motor fluids identical to the aspirated fluid.
- Recovery of condensed vapours in the separator tank, with pressurised discharge without an extraction pump.
- Compact design, small footprint and ready-to-connect delivery.
Our POLYVAC hydro-ejectors can be configured to meet your specific requirements:
- Combined with a steam ejector or ROOTS depressor for higher flow rates and vacuum down to 0.5 mbar abs.
- Air ejector for a final vacuum of 30 to 3 mbar abs at reduced flow rate.
- Suction non-return valve.
- Centrifugal pump with magnetic or external drive.
- Heat exchangers (BEM-type tube bundles, removable plates, immersed or external heat exchangers).
- Complete instrumentation (measurement, safety, automation).
- Automatic condensate drain valves.
- Secondary wash column on vent.
- Hydraulic guard for enhanced safety.
POLYVAC H Series

Principle: a high-efficiency liquid jet ejector draws in non-condensable gases, condenses or neutralises vapours, and recycles the liquid via a centrifugal pump.

Typical applications: chemical industries, ATEX zones, processes requiring washing of toxic or malodorous gases.

POLYVAC V Series

Example 1: POLYVAC II VF
Inlet gases: air + acid vapours (HCl, HBr, Br, etc.), solvents (THF, diethyl ether, toluene, acetone, methylene chloride, methanol, ethanol, ethyl acetate).
Suction flow: 250 m³/h
Suction pressure: 5 mbar abs
Steam consumption: 18 kg/h at 5.5 bar eff.

Example 2: POLYVAC III VF
Inlet gases: air + acid (HCl) + solvent (xylene).
Suction flow: 100 m³/h
Suction pressure: 30 to 1013 mbar abs.