PALM OIL PROCESSIN

GEPF 4707

ASSOC. PROF. DR. MOHD HALIM SHAH BIN ISMAIL

Palm Oil Industry in Malaysia

One of The World's Largest Palm Oil Exporter

Malaysia currently accounts for 39 % of world palm oil production and 44% of world exports.

Being one of the biggest producers and exporters of palm oil and palm oil products.

Malaysia has an important role to play in fulfilling the growing global need for oils and fats sustainably.

Oil palm (Elaeis guineensis) was first introduced to Malaysia as an ornamental plant in 1870.

Now become the cornerstone of the country’s agricultural sector, with a planted area of 3.3 million hectares (1999), which has grown every year.

In Malaysia, the oil palm planted is mainly the hybrid tenera which yields about 4.0 tonnes of palm oil per hectare and 0.6 tonne palm kernel meal (PKM).

Harvesting of oil palm bunches commences 30 months after planting reaches maturity in three years and has an economic life of about 25 years.

The fruit is about the size of a small plum and grows in large bunches weighing 10kg-20kg.

A bunch can have up to 2000 individual fruits.

The material bred from these palms is referred to as Dura Deli . It is very stable and uniform in Oil and kernel content.

An average content of the fresh fruit bunch (FFB) is 25% oil, 5.5% kernel, 6% shell, 9% fibre, 25% empty bunch (EB) and the balance is moisture.

In recent years another parent has been introduced to produce the material referred to as Tenera.

THE PALM

The same Dura Dali palm is used to produce the Tenera palm seed but it is pollinated with pollen from a selected Pisifera palm (the selected Pisifera when self pollinated produce fruit with a small kernel and little shell).

The resultant Tenera material produces fruit with more oil than Dura material, the same kernels as Dura but less shell than Dura.

THE PALM

Each fruit consists of a hard kernel (seed) inside a shell (endocarp) which surrounded by a fleshy mesocarp.

The mesocarp contains about 49% palm oil and the kernel about 50% palm kernel oil.

FFB Grading1.Unripe Bunches

2.Ripe Bunches3.Over Ripe Bunches4.Empty Bunches5.Dura Bunches6.Long Stalk Bunche7.Old Bunches8.Dirty Bunches9.Damage Bunches10.Abnormal Bunches11.Small Bunches

Unripe BunchThe Bunch which has purplish

color fruits and without detached fruit let

Unripe BunchThe bunch which has reddish orange

color fruits and has less than 10 detached fruitlets.

Ripe BunchThe bunch which is reddish orange

with at least 10 detached fruit lets and more than 50 % of the fruit still attached to the bunch

Over Ripe BunchThe bunch which is darkish red with

more than 50 % of detached fruitlets but at least 10% of the fruits still attached to the bunch

Empty Bunch

The bunch which has more than 90% of its fruits have detached from it

Dura BunchThe bunch which has the following

characteristicsCharacteristics Value

Shell Thickness 2 – 8 mm

Shell Fruit Ratio

25 - 50 %

Mesocarp Fruit Ratio

20 – 60 %

Kernel Fruit Ratio

4 – 20 %DURA(Thick Shell)

Tenera Bunch

TENERA(Thick

Mesocarp)

Long Stalk Bunch

The bunch has stalk longer than 5 cm in length measured from the lowest level of the bunch stalk

Old Bunch

The bunch which has been harvested and left at the field more than 48 hours. It is normally dry and blackish in color

Dirty Bunch

The bunch which more than half of its surface covered with mud, sand, other dirty particles and mixed with stone or other foreign materials.

Damaged Bunch

The bunch which has more than 30% of its fruits damaged by pest, such as rats etc

Abnormal BunchThe bunch which has more than

50% parthenocarpic fruits and has abnormal size and density.

Small BunchThe bunch which has small fruits and

weight less than 2,3 Kg.

WHY FRUIT GRADING ARE

SO IMPORTANT ?

Harvesting is normally a 6 to 8 day cycle. It is important that the fruit must not be harvested before it is ripe, that is until the process of photosynthesis, which converts the carbohydrates into fat, is well in advance.

The oil content of unripe mesocarp may be in the order of 35% whereas the oil content of ripe mesocarp is usually between 50% and 55%.

The harvesting of under ripe fruit can cause losses in the order of 8% of the possible yield.

HARVESTING

The FFA content of the oil in the bunch before harvesting may be in the order of 0.1% whilst the FFA of the oil in the same bunch when it is received at the mill will never be less than 1%, normally in the order of 3%, and is frequently above 3% under bad conditions.

A low FFA content is the first characteristic to which edible oil refiners pay attention.

A premium of 1% of the sale price is paid for every one percent, should the FFA content be below 5% and the refining loss will be 1.25% to 1.80% per 1% of FFA.

FREE FATTY ACID (FFA)

The rise in the FFA content from harvest to mill will make possible the harvesting of riper fruit with higher oil content and recovery of higher quality oil with a lower FFA.

The riper the fruit the more vulnerable it is to damage during transport and handling.

Of all different stages of processing, the harvesting of the palm tree and the transport of fruit to the edible oil refiner has the most effect on quality.

FREE FATTY ACID (FFA)

• SterilisationThis is the first operation in the processing line of palm oil.

This involves the steaming of the harvested fresh fruit bunch (FFB) to loosing the fruit from the bunch and burst open the oil cell.

• StrippingThis is the next stage after sterilisation and it involves the removal of the fruit from the bunches using a stripper.

• DigestionThis process is the next stage after stripping and this involves the pounding of the fruits which have been removed from the bunch.

• ClarificationFinal stage in the processing of palm oil. Dirt, moisture and other impurities is removed from the crude palm oil by this process.

Stages of Processing

OIL PALM PROCESSING

Flowchart of Processing CPO

FFB Reception

The FFB bunches loaded on trucks, cages or trailer are weighed on arrival at the mill and on departure when empty by weighbridge of 50 ton capacity and automatically recorded, that is computerised.

After weighing-in process of the truck, cage or trailer, the PFB are dumped into the inclined hopper at the ramp that will hold 900 mt PFB ( 2 lines of 15 bays x 30 mt PFB ).

FFB ReceptionModern mills in Malaysia are equipped with the

following in the reception area of the mill: A. Load cell (pitless) 50 tons weigh bridge of

3.3m W x 15m L and computerised. B. Larger loading ramp with double door

hoppers of 30mt capacity per bay. C. FFB Cage and bogie with capacities of 5, 7

and 10 mt of wheel spanned of 800mm gauge.

D. FFB loading into cages by conveyor system E. Straight line railway system with Cage

transfer carriage located at both ends of the railtrack system to facilitate easier operation of the 2-door sterilizer and shunting of the cages can be handled easily with the capstan and Bollard.

FFB Reception

On opening the hopper door ( 2 doors to a bay ) the bunches drop into the 7mt cages with bogies placed beneath it.

The loaded PFB cages are then conveyed by the transfer carriage on the rail track and pushed into the sterilizer, by a winch and ballard system for sterilization.

Reception Station

Sterilization The sterilizer process is done in 5, 7 and

today 10 tons capacity FFB cages which are pushed into long cylindrical steel vessel with special doors and subjected to steam at approximately 3 BAR.

One of the effects of sterilisation is to inactivate the fruit enzyme.

Once this enzyme has been inactivated the rise of the FFA is virtually stopped.

The objective after harvesting is to sterilize the fruit as quickly as possible with the minimum of handling and damage.

Sterilization

In addition to arresting the development of the FFA content, the sterilizing of the fruit also facilitates:

a. The purification of the palm oil by

coagulating nitrogenous and mucilaginous matter and thus preventing the formation of emulsions during verification of the crude oil.

b. The extraction of the crude palm oil by freeing the fruits from the bunch stalks and by breaking the oil cells in the mesocarp.

Sterilization

Majority of mills today has programmable automatic control systems to cater for proper sterilization of 90-minute cycle.

Sterilisation is a simple process but it is essential, for the proper operation of the mill so that it is done correctly.

This operation is the largest user of steam in the mill.

Sterilisation Station

Threshing Station

Pressing Station

Clarification Station (Screening)

Clarification Station (Clarifying)

Clarification Station (Oil Recovery)

Clarification Station (Purifying)

Clarification Station (Moisture Removal)

Storage of CPO

Kernel Recovery Station (Depericarping)

Kernel Recovery Station (Nut Cracking)

Kernel Recovery Station (Winnower)

Kernel Recovery Station (Hydro Clay Bath)

Kernel Storage

The two oils have very DIFFERENT composition.

Palm oil contains mainly palmitic (C16:0) and oleic acids (C18:1), the two most common fatty acids in nature, and is about 50% saturated.

While palm kernel oil contains mainly lauric acid (C12:0) and is more than 80% saturated.

This point is important because the two oils are often confused by nutritionists.

In palm oil, most of the fatty acids are C16 and higher, while in palm kernel oil, they are C14 and lower.

Palm oil has iodine value (IV) 50 minimum, while palm kernel oil has 21 maximum.

Semi-solid in temperate climates, palm kernel oil can be fractionated into solid and liquid fractions known as stearin and olein respectively.

Palm Oil Properties

These are then physically refined, bleached and deodorized or chemically neutralized, bleached and deodorized to give the RBD and NBD grades used in the food industry (Pantzaris and Ahmad, 2001).

The process of fractionation can be carried out either before or after the refining, according to conditions.

The major fatty acids in palm kernel oil are C12 (lauric acid) about 48%, C14 (myristic acid) about 16% and C18:1 (oleic acid) about 15%.

Palm Oil Properties

No other fatty acid is present at more than 10% and it is this heavy preponderance of lauric acid, which gives palm kernel oil and coconut oil, their sharp melting properties, meaning hardness at room temperature combined with a low melting point (Pantzaris and Ahmad, 2001).

This is the outstanding property of lauric oils, which determines their use in the edible field and justifies their usually higher price compared with most other oils.

Because of their low unsaturation, the lauric oils are also very stable to oxidation.

Palm Oil Properties

Next slide shows the fatty acid composition of palm kernel oil, its similarity to coconut oil and their differences from palm oil, the co-product of palm kernel oil and typical non-lauric fat.

Even after full hydrogenation, the melting point of palm kernel oil does not rise much above mouth temperature and fractionation gives a stearin which is even sharper melting.

Palm Oil Properties

Percentage of Fatty Acid Composition in Palm Kernel, Coconut & Palm Oil

Sharp melting fats leave a clean, cool, non-greasy sensation on the palate, impossible to match by any of the common non-lauric oils.

This figure shows the melting behavior in terms of solid fat content (SFC) values of palm kernel oil (PKO), palm kernel stearin (PKS) and hydrogenated palm kernel stearin of melting point 35ºC (HPKS 35), together with cocoa butter (CB) and palm oil (PO) for comparison.

Palm oil contains about 1% minor components. The major constituents are carotenoids, vitamin E and sterols (Basiron and Chan, 2004).

The carotene concentration is around 500 to 700 ppm. Carotene has been concentrated from palm oil successfully.

The concentrate is rich in pro-vitamin A which is normally destroyed during processing.

The major carotenes in the carotenoid concentrate are alpha and beta-carotenes and they can be diluted to various concentrations, from 1% to 30%.

Palm Oil Properties

The vitamin E content in palm oil is unique in that it is about 600 to 1,000 ppm. It is present as tocotrienols (70%) rather than tocopherols (30%).

It confers on the oil a natural stability against oxidation and a longer shelf-life as well as a potent ability to reduce low density lipoprotein-cholesterol and anti-cancer properties.

Palm oil also contains 250 to 620 ppm sterols. Beta-sitosterol is the major constituent at 60%. It is potentially hypocholesterolemic.

Palm Oil Properties

Flow Diagram of Palm Oil Extraction

Refining Process for Crude Palm Oil

Composition of Fresh Ripe Fruit & Mesocarp (%) – Dry Basis

Power Plant Operation In A Typical Palm Oil Mill

The operation of power plants within a palm oil mill is not so complex.

These plants are normally staffed by local steam drivers and engineers.

Next figure shows the case of a typical 60 tons FFB (fresh fruit bunches) per hour mill operating 20 h a day.

A total of 23% by weight EFB (empty fruit bunches) or 13.8 tons of EFB per hour is sent back to the estate to be used as mulch in the fields.

Power Plant Operation In A Typical Palm Oil Mill

The fuel produced from the waste comes from:

Shell amounting to 6%, out of which about 30% is dry enough to be used as boiler fuel, or 1 ton/h and Fibre amounting to 14% or 8.4 ton/h

Schematic Diagram Of A Typical Power House In Palm Oil Mill

The power requirement of the mill is 15e17 kW per ton FFB or 1020 kW for a 60 tons FFB per hour mill.

This is typically met by a non-condensing turbine using steam with a pressure of 21-bar gauge and exhausting at 3-bar gauge.

The size of the generator is about 1.2 MW.

When the mill is not in service, a diesel generator takes over to supply security lighting and domestic supply.

Power House In Palm Oil Mill

Two units are usually installed: one of 800 kW and another of 250 kW.

In a mill break down which may last a while, the large diesel generator will be operated to supply power to some plants in the nut station, effluent plant, water works, lighting etc.

The diesel generating sets are not required if the mill is close to the national electricity board grid and is connected to it.

Power House In Palm Oil Mill

New schemes for grid-connected power plants under the small renewable energy programme involve the construction of boilers burning EFB and producing up to 10 MW of power, which can be sold to the national electricity board.

It is envisaged that such a plant will serve several mills.

Another concept is to produce methane gas from POME, and burning the gas in boilers, gas engines or gas turbines.

It has been shown that such plants can meet the power and steam needs of the mills and still allow power export.

Power House In Palm Oil Mill

Analysis of Steam Distribution in

25 tonne/hour Palm Oil Mill

ANY QUESTIONS

?