The continuous modular system for olive oil extraction.

A lift conveyor with acid-proof rubber belt (1) transports olives from the hopper to the washing machine. During the final part of the run, leaves are removed from the olives by a centrifugal fan with special profile self-cleaning paddles (2). In the hydro-pneumatic washing machine (3) a bubbling air jet avoids olives coming in contact with metal and being crushed: an exclusive feature of Pieralisi washing machines.

After passing through a vibrating drip grate, the olives are gathered in a hopper (4) and from here - by means of a screw elevator (5) - are fed into the crusher (6) where a hammer with heavy metal plates and a grate provide for the perfect breaking of the oil pockets and the carefully gauged crushing of the stones. Plates and grate are interchangeable.

The pulp obtained falls into the 2-overlapping stage (capacity 0.7 ton each) kneader (7); homogeneous heating and helicoidal plates ensure perfect processing. The heating is obtained with controlled temperature water circulating in the hollow of the kneader: max. surface and max. exchange capacity (5,700 sq cm/100 kg of olives); possibility of changing temperature in the different stages.

The pulp is dropped from one stage to the other through airtight hatches that can be opened from the outside.

A single-screw pump (8), which ensures constant feeding and absence of emulsion, conveys the pulp to the centrifugal extractor (9), where the three phases - oil, husks and waste water - are separated. The oil, after undergoing preliminary straining in a vibro-filter (10), is pumped to the separator (11) for elimination of the still-existing solid particles and water.

A heating plant with waste husk or Diesel oil stove produces the hot water needed for heating the kneader, controlling automatically and continuously the different temperatures. A control panel (12), with safety and interlocking equipment, completes the system.

NOTES:

• All the parts in contact with the pulp are made of stainless steel.
• The kneader stages are made of stainless steel.
• The centrifugal extractor and separator drums are made of hardened and tempered stainless steel with high mechanical resistance.
• The centrifugal extractor screw is protected by tungsten carbide facing applied by the continuous process.
• All continuous modular plants can also operate on the two-phase system.