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Cleaner Production
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• Working conditions improved in the animal feed production units.
• Annual recovery of oil, ghee, fats, and animal fodder amounted to
$90,705.
• Capital investment costs reduced by about $87,720.
• BOD loads in the final effluent reduced by 85%.

Final remarks
The following achievements were obtained as a result of applying the
cleaner production technique:

• Conservation of natural resources.
• Avoidance of end-of-pipe treatment.
• Reduction of capital costs.

Tanta Company has applied the “win–win” strategy where the environ-
ment, the consumer, and the worker were protected while improving the
industrial efficiency, profitability, and competitiveness.

Oil and soap sector: Waste minimization at edible
oil company
This case study will present different steps for the oil extraction process at
Sila Oil Company, located in Fayoum, Egypt, highlighting the different cleaner
production techniques that could be implemented in some or all of these steps.
The CP techniques that were utilized in this case study are good house-
keeping, equipment modification, input material change, and on-site recycling.
Finally, it was noticed that cleaner production techniques not only result in
substantial financial savings due to reduction in energy and raw material
consumptions, but also result in better quality products within a more envi-
ronmentally friendly process (SEAM 1999c).

Process description
Extraction of oil from oil-bearing seeds consists mainly of four major steps:

• Pre-treatment of the raw material: During this step the oil-bearing
seeds are cleaned, dried, and de-hulled. Then clean seeds are weighted
and passed to a de-stoner and a magnet to remove stones and metals,
then prepared for oil extraction and cooking.
• Extraction of oil: There are three main methods for extracting oil from
seeds, which are: hydraulic pressing, expeller pressing and solvent
extraction. In this process 50% of the crude oil content is extracted
using expellers, while the seed cake containing 30% oil is sent to sol-
vent extraction unit where the seed cake is mixed with hexane to pro-
duce a solvent oil mixture (miscella), and an extracted meal (2% oil
content), which is sent to a desolventizing, toasting, drying, and cooling
unit. Crude oil is extracted from miscella by a three stage evaporation