See this web site and the pictures to see if this fits your needs. This type of pump has that churning type action of little duck feet and it is used in many industries.

Due to a number of carefully engineered features, the Megator Rotary Lobe Pump manages such a task whilst ensuring a low life cycle cost.

The gentle action of the two interacting rotors creates a fluid movement through the pump, with minimal damage to suspended particles. Various types of rotor materials can be used, combined with a wide range of materials for all other wetted parts, resistance to wear and corrosion are obtained.

The special design of the Megator Lobe pump allows dry running, as the standard mechanical/lip - seal system is constantly lubricated. The same lubrication acts as a seal detector, allowing the user to react swiftly in case of any leaks occurring.

Typical fluids handled with the Megator Lobe Pump are:

Sludge with high dry-matter content, mud slurries, chemicals, centrifuge feed fluid, meat offal, cement slurry, gypsum, sauces with vegetables, marmalade etc.
http://www.megator.co.uk/lobe_pump.htm

Johnson Pump UK Ltd.
Positive-displacement, rotary lobe pumps for food processing, industrial, chemical, biotechnology, and pharmaceutical markets.
Category: United Kingdom > England > East Sussex > Eastbourne > Industrial Pumps
www.johnsonpump.com

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Note added at 18 days (2006-11-29 04:48:47 GMT) Post-grading
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