Basic milling technology related to crude dilution control has not made significant advances in the last 25 years. Currently, there are no reliable methods of maintaining the oil to crude palm oil ration and in actual practice most mills do not alter dilution control with widely fluctuating mill throughputs. Crude palm oil that is discharged from the presses is highly viscous. Thus, separation of the oil from the solid and water is difficult without the addition of dilution water. Hot water is therefore added to the press liqour to dilute it. The dilution provides a barrier causing the heavy solid to settle to the bottom of the container while the lighter oil droplets rise through the sludge phase to the top when heat is applied. In practice it has been found that 38% to 40% of the crude oil will be the best for good separation the settling tank (Mongana Report, 1995). It has also been found that excessive use of water in the process will result in poor settling rate and can cause higher oil losses in the waste water.

Main Research: Fatah Yah Abd Manaf