BRIEF PROCESS DESCRIPTION

1.1 Physical Refinery Plant

The main objectives of physical refining process are to remove Free Fatty Acid (FFA), colour and odour of the CPO, which is the raw material of the process. The plant has three main sections that are responsible for the three consecutive steps of the physical refining process namely degumming, bleaching and deodorization.

Degumming

(i) Degumming step is commonly known as pre-treatment step of the

physical refining process. It aims to remove gums and other impurities that are contained in the CPO.

(ii) Prior to degumming, the incoming CPO is heated from 50oC to 90oC.

(iii) Then the heated CPO is mixed with phosphoric acid in a dynamic mixer and further drawn into degumming reactor with retention time of 20 minutes.

(iv) During the retention in the degumming reactor, sparging steam will assist further heating of the oil.

(v) The degummed oil with temperature of 95oC will then be fed to the bleacher for the bleaching step.

Bleaching

(i) Prior to bleaching step, the degummed oil is mixed with bleaching

earth in the oil/earth mixer. The bleaching earth is proportioned by an automatic feeding system.

(ii) The degummed oil mixed with bleaching earth is then drawn into bleacher where the bleaching process takes place for about 30 - 50 minutes at 100oC – 105oC.

(iii) The output from the bleacher known as Bleached Palm Oil (BPO) is passed through the Niagara Filter in order to separate the spent bleaching earth and other impurities from the oil. BPO from the Niagara Filter is then pumped into filtered oil tank as a temporary storage before further processing.

(iv) Usually, the BPO from the filtered oil tank will pass through a second filter, called Polishing Filter before it is passed to the deodorizer.

Deodorization

(i) Deodorization is the most crucial step in refining process. It is a steam distillation process that occurs at high temperature and high vacuum.

(ii) BPO from the polishing filter is heated up to 260oC under vacuum. Steam and water are adjusted in order to maintain a vacuum of approximately 5 torr.

(iii) Direct steam functions to readily remove the free fatty acids, aldehydes and ketones residuals that cause the undesirable odors and flavours.

(iv) The fatty acid vapour is pulled out from the column by the vacuum system and trapped in the fatty acid condenser and then further cooled in the fatty acid cooler and discharged to the fatty acid storage tank as palm fatty acid distillate (PFAD).

(v) The bottom product of deodorizer is Refined Bleached Deodorized Palm Oil (RBDPO) with temperature approximately 260oC. The RBDPO is pumped through plate heat exchanger to exchange the heat with feed CPO before it undergoes final cooling and pumped to the storage tank with temperature 50 - 80oC.

1.2 Dry Fractionation Plant

Fractionation aims to separate the liquid part of RBDPO which is olein (RBDPL) from the solid part of the RBDPO namely stearin (RBDPS). The feed raw material for the fractionation plant is RBDPO that would produce olein as major product and stearin as by product. There are three stages included in the dry fractionation process.

Homogenization

The feed RBDPO is initially heated in a plate heat exchanger. This is to melt all solid oil particles in the feed RBDPO in order to obtain a homogenize oil.

Crystallization

(i) The heated RBDPO is then fed into the crystallizer. (ii) The RBDPO is cooled by the cooling coil which in turn is circulated

by the cooling water. The temperature of the cooling water is set to follow a defined cooling curve programmed in the temperature controller. The temperature of the RBDPO in the crystallizer will decrease according to the defined cooling curve of the cooling water and this is how the RBDPO is cooled in order to allow the crystal nuclei formation. The temperature of cooling water circulated in the cooling coils is adjusted by a control valve that

regulates the amount of hot water, cool water or chilled water that enter the water inlet to the crystallizer based on the temperature indicated by the defined cooling curve.

Membrane filtration

(i) Solid oil crystals (stearin) is separated from the liquid oil (olein) in

a membrane filter press which is an automatic filter with side plate shifting. There are 3 membrane filter press available in this plant.

(ii) The olein is pumped to the olein storage tank. (iii) On the other hand, the stearin separated by the membrane filter

press is melted in the stearin melting tank before it is stored or packaged.

(iv) Any remaining olein in the stearin can be recovered by squeezing the stearin cake.

1.3 Kernel Crushing Plant

Kernel Crushing Plant aims to extract oil from the palm kernel. The products are known as crude palm kernel oil (CPKO) and palm kernel expeller (PKE) as a byproduct. The method of extracting is by crushing the palm kernel through series of expellers. The oil is filtered through Niagara filter before being stored at the final oil tank.