Edible Oil Extraction Plant

Brief Overview
 

Capacity:

550 T/D

Technology:

Krupp Extechnik

Built:

1975

Shut Down:

2002

Raw Materials:

- rap seed
- sunflower seed
- soya bean

Products Produced:

Edible Oil

Utilities Consumption:

- 52.7 kWh/ton of oil
- Steam 8t/hr
- Water – closed circle 900 cbm
- Solvent is C6H14 Isohexane
- Consumption 3 kg/dry cake
- Manpower 3 man/shift

Documentation:

Available
 

Process Description

Extraction
The principle is to extract oil from seed press cake or soya bean by organic solvent (isohexane). Raw materials for extraction contents oil, plant netting, water, and air. Solvent "pusshes out“ the air from raw materials, fill up the cavities, dissolves the oil. Solution of oil and solvent sticks on the particles and its concentation comes into balance with concentation of the free solution around the particles. This concentration balance moves countercurrent – wise by bringing more and more diluted solution up to clear solvent. Such diffusion operation takes place in extractor.

Extractor (CS, only head and conveyors SS)
It is two floor cylinder (diameter 6.25 m x 7.23 m high). Each floor has perforated bottom made out of lamells with conical slots (0.8 mm). Rotor has 18 chambers into them is the seed press cake feeded by three screw conveyors (varispeed). Chambers rotates simultaneously in both floors. Material moves from top to the lower chamber after one revolution of the top chamber. There is a scruber above each chamber which sparys solution or clear solvent. (clear solvent at the last quarter of lower chamber only). There are two discharge screw conveyers 2 meters under the extractor bottom. From there material (solvent content 25-30%) moves to toaster. Solvent is feeded into extractor continuously and solution is pumped out continuously too. Solution at the extractor exit contents about 20% of oil.

Oil – solvent separation
- Separation of impurities
- Destilation of solvent
- Condensation of solvent vapor and water
- Water-solvent separation

Impurities separation
In two levels-sedimentation tanks and hydrocyclones.

Solution destilation
In three levels-falling film evaporator, rising film evaporator, stripping column (all CS). All units are evacuated by water sealed vacuum pump.

Vapour condensation
In heat exchangers and two colums (Raschig rings) sprayed by mineral oil for solvent vapour absorption.

Water-solvent separation
Separation by differnt densities in tank.