WO2004061059A2

WO2004061059A2 - Recovering oil from palm mesocarp fibres

Info

Publication number: WO2004061059A2
Application number: PCT/SG2004/000002
Authority: WO
Inventors: Kee Seng Goh; Cheng Huat Goh; Eng Yau Ma; Liang Lee; Chee Heong Ng; Tiam Aik Tan; Taran Tej Singh
Original assignee: EONCHEM TECHNOLOGY Sdn Bhd; LIM KIAN HIN
Current assignee: EONCHEM TECHNOLOGY Sdn Bhd; LIM KIAN HIN
Priority date: 2003-01-06
Filing date: 2004-01-06
Publication date: 2004-07-22
Anticipated expiration: 2005-07-06
Also published as: MY148525A; WO2004061059A3; MY137253A

Abstract

The invention discloses a process and apparatus to extract remaining oil from mesocarp fibres of oil palm after initial extraction of oil. The process includes the following steps: reducing the moisture content of the mesocarp fibres to below 10 % by weight; subjecting the mesocarp fibres to a solvent in an enclosed chamber at a temperature between 45 to 55°C to yield a miscella and deoiled mesocarp fibres; removing the miscella containing oil, solvent and moisture; removing the solvent from the deoiled mesocarp fibres produced; separating oil, solvent and moisture respectively from the miscella. The solvent used is food grade hexane. Content of hexane in the extracted palm oil is below 0.1 % by weight. Remaining oil content of the deoiled mesocarp fibres is below 0.5 % by weight.

Description

RECOVERING OIL FROM PALM MESOCARP FIBRES

FIELD OF INVENTION

The present invention relates to a process of recovery of residual palm oil from palm fibres, more particularly mesocaφ palm fibres. More particularly, the invention is directed to a solvent extraction process whereby residual palm oil in mesocaφ fibres of palm fruits is recovered.

BACKGROUND ART Among plants producing edible oils, the oil palm yields the most oil per hectare.

With the recent introduction of African Weevil Eloeidobiuss Kamerancius in 1981, especially in Malaysia the yield per hectare has increased. A typical palm fruit is a drupe, oval in shape and contains a kernel, which is the true seed. The kernel is surrounded by the fruit wall (pericaφ) made up of the hard shell (endocaφ), oil bearing tissues (mesocaφ) and the skin (exocaφ).

The prior art process for the extraction of palm oil uses basic technology developed some 30 years ago in Africa. The palm oil milling process known in the art comprises the major steps of digestion of fruit bunches (FFB), oil extraction, oil clarification, sludge separation and kernel separation. There are two main products derived from the palm oil milling process namely palm oil and kernels. There are several methods of oil extraction which are known in the art. They are generally classified as the wet process, using a wash liquid to free the oil in palm fruit and the dry process for example batch type hydraulic press, a semi continuous type hydraulic press and a continuous type screw press, etc. Each process has its advantages and disadvantages. The wet process ensures that there is no nut breakage but results in the accumulation of unacceptably large quantities of fibres in the wash liquid/oil mixture. Additional efforts have to be expanded to remove the fibres from the said mixture. The continuous screw press (a dry process) gives high throughput, and operates at comparatively low energy cost, but tends to result in a high amount of nut breakage when the operating conditions are not ideal. Nut breakage in the screw press process is not desired as it would result in deterioration of crude palm oil quality as well as higher costs of maintenance of presses. The kernel is obtained by separation from the nut by a cracking process. Other by-products such as fibres, shells, and empty bunches are also produced.

In the prior art, after crude palm oil is extracted from digested palm fruit by pressing, the mesocaφ fibre still contains about 5% oil, which cannot be ideally further extracted by increased pressure as the excessive pressure would result in higher quantities of broken kernel, deterioration of crude palm oil quality as well as higher cost of maintenance of presses. The fibres containing 5% oil is usually used as fuel, burnt in the steam boilers in the palm oil mills, thereby losing useful palm oil. Any further excess palm fibres from the mill are disposed off as mulches. Basically the mesocaφ fibres will be produced as by-products and used as fuel. If the quantities of broken kernel from pressing are intended to be lower, a lower pressure in the oil presses must be used. But this approach results in higher (10-12%) residual oil in the fibres. There is a need to produce an efficient method of extracting the residual palm oil in the mesocaφ fibres without increasing the quantity of broken nuts. Trials have been done using hexane extraction but it was not successful or commercially viable. Typically the rate of usage of hexane was 22 litres per tonne FFB. Such a rate of wastage of hexane is not commercially viable or economical. For this reason, no attempts have been seriously made to extract the remaining 5% oil from the mesocaφ fibres. Industry did not know how to extract the residual palm oil from the mesocaφ fibres with a minimum acceptable loss of hexane in the extraction process. SUMMARY OF INVENTION

The invention discloses a process and apparatus to extract remaining oil from mesocaφ fibres of oil palm after initial extraction of oil. The process includes the following steps: reducing the moisture content of the mesocaφ fibres to below 10% by weight; subjecting the mesocaφ fibres to a solvent in an enclosed chamber at a temperature between 45 to 55°C to yield a miscella and deoiled mesocaφ fibres; removing the miscella containing oil, solvent and moisture; removing the solvent from the deoiled mesocaφ fibres produced; separating oil, solvent and moisture respectively from the miscella. The deoiled mesocaφ fibres contain bound moisture and oil. The mesocaφ fibres are subjected to a temperature between 100°C to 110°C and a pressure of 0.993 to 0.997 bar (absolute) in a fibre cooker to reduce the moisture content to below 10%. Then the mesocaφ fibres are cooled to a temperature between 50°C to 60°C before introduction into a band extractor enclosed chamber. In the enclosed chamber the mesocaφ fibres are moved in a forward linear direction on a reticulated moving conveyor and are subjected to a plurality of continous sprays of solvent and mixtures of solvent and palm oil in a counter-current manner. The sprayer at forwardmost position sprays solvent and sprayer at the most distal position sprays a mixture of solvent and palm oil and the sprayers from the forwardmost position to distal position spray an increasing ratio of oil to solvent.

Besides using the band extractor, a rotary cell extractor can be also used. In the rotary cell extractor, the mesocaφ fibres are moved in a forward rotary direction in a plurality of rotary cells which are subjected to a plurality of continous sprays of solvent, and mixtures of solvent and palm oil in a counter-current manner. During the forward rotary movement of cell, the fibres are washed continuously with miscella of decreasing of oil content and finally with solvent in a counter-current manner by means of a plurality of sprayers. The miscella richest in oil from either the band extractor or the rotary cell extractor is sent to a miscella holding tank. The rich miscella from the holding tank is pumped to the distillation section. The distillated crude palm oil is then pumped to storage tank.

The deoiled mesocaφ fibres obtained from the extractor are transported to an agitation chamber known as toaster. Within the agitation chamber the deoiled mesocaφ fibres are moved forward preferably in a downward direction. The temperature within the chamber is maintained at 100°C to 110°C and is subjected to counter flow of open steam of 107°C at 0.3 barg wherein the solvent in the doiled mesocaφ fibres is vapourised. This process is known as the desolventisation process. The deoiled/desolventised fibre after oil the extraction is transported back to mill by means of chain conveyor or other suitable to be used as boiler fuel. The solvent vapours formed in toaster as well as in the distillation sections are to be condensed. Solvent and water vapours condensed in condensers are combined in a receiver and the solvent is separated from water by decantation and recycled to the extractor. Uncondensed solvent from the condensers is led to a contact cooler in an absoφtion section. Thereafter the uncondensed vapours are passed through an absorber.

The solvent gets absorbed in a spindle oil. Absorbed solvent is passed through evaporator and released and taken to another condenser where it is condensed and combined with solvent recovered from other sections. Uncondensed gasses are removed from the absoφtion section through a vent. The solvent used is food grade hexane. Content of hexane in the extracted palm oil is below 0.1% by weight. Remaining oil content of the deoiled mesocaφ fibres is below 0.5% by weight.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the above.

DETAILED DESCRIPTION

The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, wherein:

Figure 1 shows the flow chart of the solvent extraction plant.

Figure 2 shows the mass balance for 15 tons/hr or 360 tons/day (24 hours).

Figure 3A and B shows the flow sheet for solvent extraction plant.

Figure 4 shows a diagrammatic plan view of a rotary cell extractor. Figure 5 shows a diagrammatic side sectional view of the rotary cell extractor.

The solvent extraction process consists of a first phase of preparing the palm fibres followed by second phase of solvent extraction of the palm oil in the mesocaφ fibres. The first phase in general term involves the reduction of moisture content of palm fibres extruded from the screw press. The mesocaφ fibres produced by the palm oil mill after being subjected to the screw press contains 30-40% moisture. For efficient solvent extraction the moisture content has to be reduced to 8-10%. This is achieved by heating the fibres in a fibre cooker/dryer (10) at a temperature between 100-110°C under reduced pressure, using jacketed steam. The reduced pressure in the dryer (10) is preferably maintained 0.995bar absolute. The steam pressure in the jacket is maintained at 8-10barg and at a temperature of 175-184°C. The temperature of the incoming fibres before feeding onto the fibre cooker/dryer (10) is approximately 45°C. The heated fibres are then cooled in a cooler (12) to a temperature of 55°C. The heating of the mesocaφ fibres also facilitates the rupture of the oil bearing cells within the fibres. This rupture of cells is desired as it enables the solvent to penetrate the oil bearing cells for better extraction of oil.

The dried fibres now containing 10% or less oil are then transferred to the second phase.

The solvent extraction which is the second phase consists of 5 main processes: i) Extraction process ii) Miscella Distillation process iii) De-oiled Fibre De-solventisation process iv) Condensation process v) Absoφtion process The dried fibres from the preparatory section are conveyed by Redler conveyor to a band extractor (14). Other types of material handling equipment can be easily adapted. A rotary valve regulates the feed rate of material. Level indicators are provided on receiving hopper (16) to control low and high level of the materials in the hopper (12). The extractor (14) operates at temperature of 45-55°C and pressure between 0.993-0.997bar absolute. The extractor (14) has a slow moving reticulated band conveyor (18) inside a totally enclosed chamber (20). The band conveyor (18) is lined with perforated sheet, covered with stainless steel wire mesh for easy percolation of miscella. The band conveyor (18) moves on a rail provided inside the extractor (14). A series of sprayers (22) are located above the band conveyor (18) for spraying miscella and hexane on top of the moving material bed of fibres (30) in the extractor (14). The solvent is sprayed in 8-11 stages. Each stage of sprayer has a trough (24), heaters (26) and pumps (28) underneath. The heaters (26) consist of circulating steam jackets. The jacket steam in heaters (26) is at a pressure of up to 5 barg and temperature of 159°C. During the movement of the material bed through the extractor (14) the fibres are washed continuously with miscella of decreasing concentration and finally with fresh solvent in a counter-current manner by means of sprayers (22) arranged in a line over the bed (30). The miscella percolates through the bed (30), passes through the perforated screen of the conveyor (18) and collects in various troughs (24) located underneath the band conveyor which ultimately flows to the miscella holding tank (32). By the end of extraction cycle, oil in the fibres is reduced to less than 0.5% by weight. The fibres after the extraction process from the band conveyor (18) fall into a de-oiled fibre hopper (34) and conveyed to the desolventising section by an air tight de-oiled fibre conveyor (36). instead of using a band extractor, a rotary cell extractor (100) can be used to extract the remaining oil in the mesocaφ fibres. The detail description of the rotary cell extractor (100) is described below. The dried palm fibres from the preparatory section are conveyed by Redler conveyor to an rotary cell extractor (100). A rotary valve regulates the feed rate of material through a receiving hopper (102). The extractor (100) operates at temperature of 45-55°C and pressure of 0.995bar absolute. The extractor (100) has a slow moving rotary conveyor consisting of number of stages of moving compartments, a of stationary stainless steel grating (104) fitted between the compartments and miscella troughs (106), inside a totally enclosed chamber (108). The feed (124) consisting dried palm fibres from the fibre cooker are fed to an empty compartment which is positioned underneath the feed hopper during the rotary motion of the conveyor. Miscella that is richest in oil is sprayed into the compartment immediately adjacent to the compartment into which the palm fibres are fed. A series of progessively leaner miscella sprays (110) is sprayed counter-currently into the compartments filled with fibres, via a plurality of sprayers. The miscella circulated in each compartment percolates through the fibres and then passes through the grating (104) acting as a screen, into trough beneath and recycled back to the top of preceding compartments with the help of pumps (112) fixed under each trough (106). Each sprayer has a heater (114) consisting of steam jackets. The jacket steam in the heaters (114) is at a pressure of up to 5 barg and temperature of 159°C. During the forward rotary movement of the compartments filled with fibres, within the chamber (108), the fibres are washed continuously with miscella of decreasing concentration of oil and finally with fresh solvent (122) in a counter-current manner by means of sprayers (110). The miscella at each stage percolates through the fibres (116), passes through the perforated grating (104) and collects in respective troughs (106) located underneath the grating. The miscella richest in oil concentration flows to a miscella holding tank (118). By the end of extraction cycle which is one revolution of rotary compartments, oil in the fibres is reduced to less than 0.5% by weight. The fibres after the extraction process from extractor (100) fall into a de-oiled fibre hopper (120) and are conveyed to the desolventising section by an air tight de-oiled fibre conveyor (126) as explained in the embodiment for utilizing the band extractor (14).

The extracted fibres retain solvent and this solvent has to be recovered. The retention varies from 25% to 30% of weight of fibre. The basic principles involved in desolventisation includes indirect/direct heating of fibres with steam to a temperature well above the boiling point of solvent and and removal of the solvent in vapour phase. Vapour of solvent is then sent to condensers via scrubber (40) where solvent is condensed and recycled to the extractor (14) together with solvent recovered from miscella distillation further down the process line. The equipment used in the desolventisation is known as the de-solventiser-toaster or an agitation chamber (38). The operating temperature is between 100-110°C and the operating pressure is between 0.993-0.997 bar (absolute). The temperature of the jacket steam is between 170°C-184°C and the steam pressure is between 8-10 barg. The extracted deoiled / desolventised fibre is transported back to the mill section by means of chain conveyor, to be used as boiler fuel or for other downstream uses.

The mixture of oil and solvent obtained from the extractor (14) is known as miscella and it normally contains 10% to 15% of oil in solvent. The rich miscella from the extractor is collected in a tank from where it is pumped to the distillation section. It is kept under vacuum by means of a series of steam ejector. The miscella is sent to a economizer (42) where the miscella is heated to 80° C. Then the heated miscella is passed through evaporator (44) and thus a part of the solvent in the miscella vaporizes immediately. The solvent vapour is led to the condensers (46, 48). The concentrated miscella is sent to a first miscella heater (50), heated between 90-100°C and sent to a first evaporator (54) for flashing solvent from miscella. The miscella from 1st evaporator is then passed through a second heater (52), heated between 100-110°C and sent to a second evaporator (56) for further separation of solvent by flashing. The oil from evaporator (56) is atomized in a stripping column (58), for final removal of the last traces of solvent from oil. Stripped crude palm oil is then pumped to storage tank and vapour from the equipments is condensed in a condenser (60).

The solvent vapours formed both in the toaster (38) as well as in the distillation sections are to be condensed. This condensation section consists of three shell and tube condensers (46, 48, 60). The miscella distillation, desolventisation and solvent absoφtion sections are appropriately connected to respective condensers depending on the pressure required in each section. Solvent and water vapours condensed in all the condensers are combined in a receiver (62). The solvent is separated from water by decantation and recycled to the extractor (14).

To minimize solvent losses due to economical and fire hazard reasons the uncondensed solvent from the condensers (46, 48, 60) is led to a contact cooler (64) in the absoφtion section, which is sprayed with cooling tower water counter-currently. Thereafter the uncondensed vapours are passed through an absorber (66) packed with pall rings sprayed counter-currently with spindle oil which absorbs the solvent. The operating temperature of the absorber is 25°C and the pressure is 0.985bar (absolute). The solvent gets absorbed in the spindle oil and the spindle oil is then passed through an evaporator (68) maintained at 90°C. Absorbed solvent from the spindle oil is thus released and taken to the condenser (60) where it is condensed and combined with solvent recovered from other sections. Uncondensed gases are removed from the absoφtion section through a vent.

The preferred parameters for the present invention are shown in Table 1. These parameters include all the equipment in the solvent extraction plant. Table 2 shows the range of parameters for the present invention.

The solvent used in this present invention is hexane (extraction grade) suitable for food industry and commercially available from Shell Chemicals. Hexane (extraction grade) is manufactured to the high standards required by the oil-seed extraction industry. Its composition complies with FAO/WHO and UK MAFF specifications for polycylic aromatics and heavy metals. It does not contain detectable quantities of chlorinated compounds.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.

TABLE 1 : PREFERRED PARAMETERS FOR THE PRESENT INVENTION

Section / Item Vessel J Steam Cooling Water Te o I

Temp Pressure Pressur e deg C " bar(abs) barg In Out

A. Preparatory Section :

1. Feed - Wet Palm Fibre 45 - - - -

2. Fibre Cooker / Dryer Clθ~) 105 0.995

3. Fibre Cooker (steam ) 184 . 10 - "

Open Steam 107 0.3

4. Fibre Cooler C IZ) 55 0.995 - - •

8. Main Plant :

1. Extractor < ι4, ι∞^") 50 0.995 - - -

- Circulation Heaters steam 159 - 5 - - .

2. De-Solventiser (Fibre outlet) ζ i v^") 110 0.995 10 . .

De-Solventisei" (Steam) 184 - 10 - -

Open Steam 107 0.3

3 D. T. Vapour Scrubber C4< 90 0 995 <_ - -

4 Distillation Section a) Miscella Tank C 3z^"> 55 0 995 - - - b) Economiser C 4a-

Shell side :

- Vapour inlet 105 0.995 - - ^'.

- Vapour outlet 70 0.990 - - -

Tube side :

- Miscella inlet 55 2 5 - - .

- Miscella outlet 80 2 2 - - - c) 1st Miscella Heater <T5Ό)

Shell side :

- Steam 159 - 5 -

Tube side :

- Miscella inlet 80 2.2 - -

- Miscella outlet 95 2.0 - . _ d) 1st Miscella Evaporator <SH- 95 0.600 - - - e) 2nd Miscella Heater <TSz)

Shell side :

- Steam 159 - 5 - .

Tube side :

- Miscella inlet 95 0.600 - - -

- Miscella outlet 110 0.400 - .

J f) 2nd Miscella Evaporator CS&j 110 0.400 - I - . g) Final Oil Stripper C S&} 115 0.130 Steam Limpets 184 10 CONTINUATION OF TABLE 1

Vessel Steam Cooling Water Temp

Section / Item

Temp Pressure Pressure deg C deg C bar(abs) barg In Out

5. Condesation Section a) Prime Condensor - 1 4 Shell side :

Vapours inlet 95 0.130

Tube side •: Cooling Water 3.0 30 35

b) Second Condensor- 2 C4-9^") Shell side :

Vapours inlet 85 0.400

Tube side ^• 3 0 30 35 Cooling Water c) Dex Condensor - 3 Ciθ~) Shell side :

Vapours inlet 70 0.990

Tube side : Cooling Water 3.0 30 35

a) Receiver fc ) 40 0.260

6. Recuperation Section : a) Contact Cooler C6 -) 34 0.990 30 33

b) Absorber C W) 25 0.985 c) Evaporator - oil outlet f>% 90 0.400 Evaporator Limpet heater 159 TABLE 2: RANGE OF PARAMETERS FOR THE PRESENT (NVENTION j Section /Item Vessel Steam Cooling Wafer Temo

Temp Pressure Pressur e de C barfabs) barg In Out

A. Preparatory Section :

1. Feed - Wet Palm Fibre 40-50 - - - -

2. Fibre Cooker / Dryer Ci 100-110 0.993-0.997 - - -

3. Fibre Cooker (steam ) 175-184 - 8-10 - .

Open Steam 105-115 0-2-0.5

4. Fibre Cooler C \X~) 50-60 0.993-0.997 - - -

8. Main Plant :

1. Extractor C l*, loθ ) 45-55 0.993-0.997 - - -

- Circulation Heaters steam 152-159 - 4-5 - -

2. De-Solventiser (Fibre outlet) C - 8) 100-110 0.993-0.997 - - .

De-Solventiser (Jacket Steam) 170-184 - 8-10 - -

Open Steam 105-115 0.2-0.5

3. D. T. Vapour Scrubber CArO ) 85-95 0.993-0.997 - -

A Distillation Section a) Miscella Tank - 50-55 0.993-0.997 - . - b) Economiser - )

Shelf side :

• Vapour inlet 100-110 0.993-0.997 - - '_ -

• Vapour outlet 65-75 0.988-0.992 • - -

Tube side :

- Miscella inlet 50-60 2.3-2.7 - - -

- Miscella outlet • 75-85 2.0-2.4 - - - c) 1st Miscella Heater CS<X)

Shell side :

- Steam 152-159 - 4-5 - -

Tube side :

- Miscella inlet 75-8S Z0-2.4 • -

- Miscella outlet 90-100 1.8-2.2 - - - d) 1st Miscella Evaporator CS^" - 90-100 0.575^0.625 - - - ^"

* e) 2nd Miscella Heater CSX)

Shell side :

- Steam 152-159 - 4-5 - -

Tube side :

- Miscella inlet 90-100 0.550-0.650 - - -

- Miscella outlet 100-110 0.37 O.425 • - • f) 2nd Miscella Evaporator C X) | 100-110 0.375^.425 - - - g) Final OS Stripper C S S~) 105-115 0.100-0.150 . .

- Steam Limpets I 1 75-184 - 8-10 - - CONTINUATION OF TABLE 2

Claims

1. A process to extract remaining oil from mesocarp fibres of oil palm after initial extraction of oil characterised in that the process includes the steps of i) reducing the moisture content of the mesocaφ fibres to below 10% by weight; ii) subjecting the mesocaφ fibres from step (i) to a solvent in an enclosed chamber (20, 108) at a temperature between 45 to 55 °C to yield a miscella and deoiled mesocaφ fibres; iii) removing the miscella containing oil, solvent and moisture from step

(ϋ); iv) removing the solvent from the deoiled mesocaφ fibres produced in step

(ϋ); v) separating oil, solvent and moisture respectively from the miscella in step (iii); and wherein the deoiled mesocaφ fibres contain bound moisture and residual oil.

2. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed in claim 1 wherein in step (i) the mesocaφ fibres are subjected to a temperature between 100°C to 110°C and a pressure of 0.933 to 0.997bar absolute.

3. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed in claims 1 and 2 wherein the mesocaφ fibres are cooled to a temperature between 50°C-60°C before introduction into the enclosed chamber (20, 108).

4. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed in claim 1 wherein in step (ii) the mesocaφ fibres are moved in a forward linear

direction on a reticulated moving conveyor (18) and are subjected to a plurality of continous sprays of solvent, and mixtures of solvent and palm oil in a

counter-current manner wherein the said palm oil is that which is extracted by

the solvent.

5. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed

in claim 4 wherein sprayer (22) at forwardmost position sprays solvent and

sprayer (22) at the most distal position sprays a mixture of solvent and palm oil

and the sprayers (22) from the forwardmost position to distal position spray an

increasing ratio of oil to solvent.

6. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed in claim 1 wherein in step (ii) the mesocaφ fibres are moved in a forward rotary

direction in a plurality of rotary cells and are subjected to a plurality of

continous sprays of solvent, mixtures of solvent and palm oil in a counter- current manner wherein the said palm oil is that is extracted by the solvent.

7. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed

in claim 6 wherein during the forward rotary movement of cell compartments filled with fibres, the fibres are washed continuously with miscella of decreasing concentration of oil and finally with solvent in a counter-current manner by means of a plurality of sprayers (110).

8. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed in claim 1 wherein in step (iv) the deoiled mesocaφ fibres are moved forward

in an agitation chamber (38) wherein the solvent in the deoiled mesocaφ fibres

is vapourised while simultaneously the temperature within the chamber (38) is

maintained at 100°C to 110°C and are subjected to counter flow of open steam

of 107°C at 0.3barg.

9. A process to extract remaining oil from mesocaφ fibres of oil palm as claimed

in claims 1 to 8 wherein the solvent is food grade hexane.

10. An assembly of apparatus to extract remaining oil from mesocaφ fibres of oil

palm after the initial extraction of oil characterised in that the assembly of

apparatus includes i) an apparatus to reduce moisture content of the mesocaφ fibres from

35% to a maximum of 10 % by weight;

ii) an extractor comprising of an enclosed chamber (20, 108), either an

endless reticulate conveyor (18), or a plurality of rotary cells and a plurality of troughs, heaters, pumps and sprayers; iii) an enclosed agitation chamber (38) with an upward flow of open steam at 107°C at 0.3barg and a plurality of steam jackets within and outside the enclosed chamber where the steam is at a temperature of between 175°C to 184°C and a pressure of 8 to 10 barg.

11. An assembly of apparatus as claimed in claim 10 wherein the apparatus to reduce moisture content of the mesocaφ fibres includes a chamber (10) with a plurality of internal and external steam jackets and wherein the steam within the steam jackets is between 175°C-184°C and at a pressure of 8-10barg.

12. An apparatus as claimed in claim 1 wherein the solvent is food grade hexane.

13. Palm oil extracted utilizing the process as claimed in any of the claims 1 to 8.

14. Palm oil extracted from mesocaφ fibres wherein the content of hexane in the extracted palm oil is below 0.1 % by weight.

15. Mesocaφ fibres from oil palm produced utilizing the process as claimed in any of the claims 1 to 8 wherein the remaining oil content of the fibres is below 0.5% by weight.

16. Mesocaφ fibres from oil palm utilizing the assembly of apparatus as claimed in any of the claims 10 to 12 wherein the remaining oil content of the fibres is below 0.5% by weight.