Olive Oil Extraction with Three-Phase Decanter Centrifuge
Complete Cold-Press Production Line Achieves Target Extraction Rate for Fresh Extra Virgin Olive Oil
Project Background
An olive oil producer required a complete extraction system capable of processing freshly harvested olives into food-grade extra virgin olive oil. The facility needed to handle the entire workflow—from olive receiving and washing through to oil separation and purification—within a compact footprint while maintaining the cold-press temperature requirements that preserve oil quality.
Customer Requirements
- Complete turnkey olive oil extraction line from raw olive intake to finished oil output
- Cold-press capability with paste temperature maintained below 27°C throughout processing
- Three-phase separation to recover oil, pomace, and vegetation water separately
- Food-grade construction with stainless steel contact surfaces meeting hygiene standards
- Compact layout suitable for their available production space
- Target throughput matching their daily harvest volumes during the picking season
ZK SEPARATION Solution
We provided a complete olive oil extraction line built around the LWS350 three-phase decanter centrifuge. The system covers every step from olive receiving through to clarified oil output, designed specifically for cold-press extra virgin olive oil production.
Process Flow
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Olive Receiving & Washing
Fresh olives are unloaded into the receiving hopper. A scraper elevator lifts the fruit to the winnowing machine where leaves and stems are removed by airflow. The olives then pass through a vibratory washer with recirculating water and spray rinse before moving to the next stage.
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Crushing
Clean olives enter the hammer mill crusher, where rotating hammers break down the fruit—pits included—into a paste with particle sizes below 5mm. This releases the oil from the plant cells and prepares the material for malaxation.
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Malaxation
The olive paste enters a jacketed malaxer tank where slow-turning paddles stir the material for approximately 30 minutes. Hot water circulating through the jacket maintains paste temperature between 22-28°C. This controlled mixing allows small oil droplets to coalesce into larger globules that separate more readily in the centrifuge.
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Three-Phase Centrifugal Separation
Malaxed paste is pumped to the LWS350 three-phase decanter. The centrifuge separates the incoming slurry into three streams: solid pomace (discharged through the screw conveyor end), vegetation water (light liquid phase), and crude olive oil (heavy liquid phase). Water addition is adjusted based on olive variety and moisture content.
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Oil Clarification
The crude oil stream passes through a vibrating screen to remove any carried-over solids, then enters a disc stack separator for final clarification. The result is clear extra virgin olive oil ready for storage or bottling.
Project Overview
- Customer Industry Olive Oil Production
- Application Fresh Olive Oil Extraction
- Decanter Model LWS350
- Processing Capacity 1.5 m³/h paste
- Bowl Diameter 350 mm
- Operating Speed 4000 RPM
- Centrifugal Force 3180 G
- Main Motor Power 15-22 kW
- Separation Type Three-Phase
Production Line Installation
The complete extraction line was installed in the customer's processing facility. The layout places equipment in sequence following the process flow, minimizing material handling distances and allowing operators to monitor each stage from a central position.
Production Line in Operation
Performance Results
- Throughput: The line processes olive paste at 1.5 m³/h, matching the customer's daily harvest volumes during the picking season
- Extraction Rate: Oil recovery meets the target yield based on the olive variety and ripeness—the customer confirmed results aligned with their expectations
- Oil Quality: Cold-press temperature control keeps paste below 27°C, preserving the polyphenols and flavor compounds that define extra virgin grade
- Phase Separation: Clean three-phase split with minimal oil loss to the pomace or water streams
- Pomace Handling: Dry pomace at the screw discharge can be collected for secondary processing or disposal without additional dewatering
- CIP Capability: The line supports clean-in-place procedures between batches and at end of day, reducing manual cleaning labor
LWS350 Three-Phase Decanter Features
Three-Phase Separation Design
The LWS series decanter uses a dual weir system to separately discharge the oil phase and water phase while the scroll conveys solids to the opposite end. This allows operators to adjust the oil-water interface position without stopping the machine.
Food-Grade Construction
All product contact surfaces are stainless steel with smooth, drainable geometry. Tri-clamp connections and sanitary seals meet food industry hygiene requirements for olive oil production.
Variable Differential Speed
The back-drive system allows differential speed adjustment during operation. This flexibility helps optimize separation when processing olives with varying oil content or moisture levels throughout the harvest season.
Compact Footprint
At 3600×1280×1050mm, the LWS350 fits into smaller production spaces while still delivering the throughput capacity needed for medium-scale olive oil operations.
Integrated Control System
PLC control with touchscreen HMI allows operators to monitor bowl speed, differential, feed rate, and torque. Preset recipes can be stored for different olive varieties or processing conditions.
Low Oil Loss
The bowl length-to-diameter ratio and internal geometry are configured for olive paste characteristics, maximizing oil recovery to the liquid discharge while keeping the pomace dry enough for handling.
Customer Feedback
"We ran the line through our first harvest season and it performed as expected. The oil comes out clean, the pomace is dry enough to handle, and we hit our target extraction rate. Setup took some adjustments to dial in the right water addition and differential speed for our olives, but the ZK technical team helped us through the commissioning. The CIP system saves us about an hour of cleanup time compared to our old manual process."
— Production Manager, Olive Oil Processing Facility
