Reducing emissions from internal combustion engines has been a major environmental concern. Up to now, most of the focus has been on exhaust gases.

However, crankcase gas has now come into focus as an area where further emission reductions can, and should, be made.

ApplicationPureVent is a compact centrifugal oil mist separator that, when connected to medium-speed diesel engines, removes 98–99.9% of oil from crankcase gases.

Recovered oil can then be re-circulated to the oil sump and used again for engine lubrication.

Two installation options are available:

• Open design for diesel engines releasing oil-free crankcase gas directly into the atmosphere.

• Closed design for gas engines re-circulating clean gas to the turbocharger, thereby reducing the atmospheric emissions further and eliminating turbocharger fouling.

Benefits • High separation efficiency. Provides 98–99.9% separation

efficiency at 40–150 m3/h.

• Stable pressure conditions. No pressure drops or clogging associated with filter cleaning solutions. The continuous outflow at constant flow stabilizes pressure in the crankcase.

• Recovered oil can be re-circulated to oil sump.

• No hazardous waste. Elimination of oily filter disposal costs.

• Long maintenance intervals. Two-year service intervals eliminate the frequent maintenance requirements associated with filter replacement.

PureVentCentrifugal oil mist separator for cleaning crankcase gas

The PureVent centrifugal oil mist separator removes 98–99.9% of oil from crankcase gases.

Operating principleThe PureVent centrifugal separator consists of a disc stack made of com-posite lightweight polymer material, which is enclosed in an aluminium housing. Connected to this is an electric motor that drives the disc stack. A frequency converter unit controls the separator motor.

Uncleaned crankcase gas enters through the inlet at the bottom of the unit and passes into the rotating disc stack.

The oil mist is separated in the disc stack; the oil drops are collected on the separator housing inner wall and drained at the oil outlet.

For gas engines, the cleaned air can be re-circulated to the engine turbo-charger. This closed system enhances engine performance and safeguards the engine since it eliminates risk of turbo -charger fouling or oil accumulation in the intercooler. Most importantly, a closed crankcase ventilation system eliminates all emissions of crankcase gas.

PureVent connected to an engine. The dotted line represents the collected oil that can be re-circulated to the engine.

Open crankcase ventilation system(for liquid fuel engines)

Closed crankcase ventilation system(for gas engines)

Clean gas outlet

Frequency converter controlled electric motor

Separator disc stack

Separator housing

Drain oil outlet

Crankcase gas inlet Flexible mounting

PureVent working principle.

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Pump curve.

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Separation efficiency vs. flow.

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Grade efficiency at 180 m3 per hour.

Operations • Maintenance intervals

– Major Service every 16000 hours or five years, whichever comes first.

• System manual includes detailed information in electronic format or paper copy:– Operating instructions– Alarms and fault finding– Service and spare parts

Technical data

Performance Capacity Max. 800 m3/hInlet gas temperature Max. 80°CNominal flow 150 m3/hCleaning efficiency at nominal flow 98%Sound level 78 dB (A)

Dimensions and weights Size (height x length x width) 698 x 342 x 401 mmWeight 39 kg

Ambient conditions (operation) Surrounding temperature +5 to +50°CElectric cabinet +5 to +45°CHumidity Must not be exposed to water

Electrical system Operating voltage Three phase 380–480 VACFrequency 50 or 60 HzPower consumption Max 1.5 kW

Separator Rotation speed 7200 rpmNumber of discs 185Housing Aluminium castingStart time 15 secondsStop time 60 secondsMounting angle Max. 3° from vertical line

EMD00108EN 1009 Alfa Laval reserves the right to change specifications without prior notification.

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How to contact Alfa LavalUp-to-date Alfa Laval contact details for all countries are always available on our website at www.alfalaval.com

Gas outlet

Oil outlet

x 114

x 1

1

x 8

9

Gas inlet

ConformityThe mark of conformity confirms that the equipment complies with European Economics Area (EEA directives).

Connections