WO2009089591A1

WO2009089591A1 - A biodiesel manufacturing system and apparatus

Info

Publication number: WO2009089591A1
Application number: PCT/AU2009/000051
Authority: WO
Inventors: Sandy Kelly; Laurence Baum
Original assignee: The Biofuel Partnership Limited
Priority date: 2008-01-16
Filing date: 2009-01-16
Publication date: 2009-07-23
Also published as: AU2009204648B2; MY163543A; CN101978027A; AU2009204648A1; CN101978027B

Abstract

A biodiesel manufacturing plant including a housing containing a power generation means, an oil expeller for mulching raw feedstock to extract raw oil from the feedstock, a mixer/reaction vessel in which the raw oil is mixed with a catalyst material and at least one separation means to separate methyl ester from other products.

Description

A BIODIESEL MANUFACTURING SYSTEM AND APPARATUS

Field of the Invention.

The present invention relates to alternative and sustainable fuel sources and particularly to a system and apparatus for the production of biodiesel.

Background Art.

Biodiesel refers to a diesel-equivalent processed fuel consisting of short chain alkyl (methyl or ethyl) esters, made by transesterification of vegetable oils or animal fats, which can be used (alone, or blended with conventional diesel fuel) in unmodified diesel-engine vehicles.

On August 31, 1937, G. Chavanne of the University of Brussels (Belgium) was granted a patent for a 'Procedure for the transformation of vegetable oils for their uses as fuels' (fr. 'Procede de Transformation d'Huiles Vegetales en Vue de Leur Utilisation comme Carburants¹) Belgian Patent 422,877. This patent described the alcoholysis (often referred to as transesterification) of vegetable oils using ethanol (and mentions methanol) in order to separate the fatty acids from the glycerol by replacing the glycerol with short linear alcohols. This appears to be the first account of the production of what is known as 'biodiesel' today.

The common international standard for biodiesel is EN 14214. There are additional national specifications. ASTM D 6751 is the most common standard referenced in the United States and Canada. In Germany, the requirements for biodiesel are fixed in the DIN EN 14214 standard and in the UK the requirements for biodiesel is fixed in the BS EN 14214 standard, although these last two standards are essentially the same as EN 14214 and are just prefixed with the respective national standards institution codes.

There are standards for three different varieties of biodiesel, which are made of different oils:

• RME (rapeseed methyl ester, according to DIN E 51606)

• PME (vegetable methyl ester, purely vegetable products, according to DIN E 51606)

• FME (fat methyl ester, vegetable and animal products, according to DIN V 51606)

The standards ensure that the following important factors in the fuel production process are satisfied:

• Complete reaction.

• Removal of glycerin.

• Removal of catalyst. • Removal of alcohol.

• Absence of free fatty acids.

• Low sulfur content.

Whilst the conventional methods and apparatus for the production of biodiesel are adequate, they are typically large, complex, fixed chemical processing facilities, requiring a large number of staff to operate the facility and also transport costs and like to move the biodiesel to the end user.

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country. Summary of the Invention.

The present invention is directed to a biodiesel manufacturing system and apparatus, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice. With the foregoing in view, the present invention in one form, resides broadly in a biodiesel manufacturing plant including a housing containing a power generation means, an oil expeller for mulching raw feedstock to extract raw oil from the feedstock, a mixer/reaction vessel in which the raw oil is mixed with a catalyst material and at least one separation means to separate methyl ester from other products.

The manufacturing plant of the present invention can take in most oil- bearing fruit — jatropha, palm, rapeseed, and the like — and process it to produce biodiesel fuel to the required European Standard. This means that the output of the plant can go straight into the tank of a modern diesel engine without modifying its settings. The process undertaken will typically be alcoholysis (often referred to as transesterification) according to the general reaction illustrated in Figure 1.

The output is ideal for smaller communities which want to use the fuel themselves. It is particularly suitable for a 100-hectare plantation, with production ranges between 1500 and 2000 litres per day - and the cost is a fraction of the rates normally charged for mineral diesel fuels.

The housing is preferably a container, normally a shipping container or the like. The container will typically be divided into a number of compartments in order to house particular components of the manufacturing plant. According to the preferred embodiment, the container will normally be divided into two compartments, the larger being approximately double the size of the smaller, thus delineating the hazardous area and separating it from the hot area.

The housing will preferably be rectangular and defined by a base wall, a plurality of sidewalls and a top wall. It is preferred that the housing has a non- corroding weatherproof tropical-grade shell. A particularly preferred material of construction for the housing is a relatively heavy duty plastic.

The housing is preferably fully sealable from the environment, but will normally be provided with at least some ventilation openings. It is preferred that ventilation driven by natural air flows is used. In order to provide such ventilation, openings may be provided in the base wall or a lower portion of the sidewalls in order to allow the escape of heavier than air gases. The housing is preferably also provided with lateral openings and events in upper regions in order to allow the escape of lighter than air gases. The container will normally be spaced above the ground surface or mount surface to promote natural flow under the container and circulation within the process area within the container.

Auxiliary circulation promotion means may be provided such as fans mounted to the power generation means for example. The fans may be associated with ducting in order to split and communicate the airflow between the compartments to provide a positive pressure to prevent any gas.

The container will normally be provided with Ming/securing/transport points or connections. These connections will preferably be accessible only from within the container, and therefore access into the interior of the container will usually be required before the container can be secured in position, or removed.

Lift points will normally be provided at at least some of the upper corners of the container, normally at each of the four upper coiners. Anchor points ^■will normally be provided at at least some of the lower corners of the container, normally at each of the four lower corners.

As stated above, the container is preferably mounted above ground level. Normally, the container will be mounted on a plurality of legs. A particularly preferred height will be 450 mm above the ground or mount surface. It is preferred that the legs used to mount the container are adjustable to allow for height adjustment of the container and also to provide levelling capabilities.

The container and/or the legs of the container will normally be mounted relative to a plinth or slab laid on the ground surface. The slab will preferably be or include concrete and will normally be reinforced.

The container may be mounted utilising sound and/or vibration absorbing material. There will normally be at least one access door to the interior of the container. It is preferred that the access door will have an at least partially clear portion in order that a user may be able to view interior of the container without opening the access door. It is further preferred that when sealed, the access door will not allow the ingress or egress of gases.

With regard to the configuration or layout of the components within the container, the power generation means will preferably be mounted at one end portion of the container with the oil expeller mounted below the power generation means. There will normally be a raw material hopper located on one lateral side of the container and communicating with the oil expeller, with a mulch exhaust on the opposite lateral side of the container. A raw oil catch tray will normally be located below the expeller. The catch tray will also typically be configured to function as a heavy gauge filter to remove larger particulate or plant matter which may escape the oil expeller. The raw oil catch tray will typically be in fluid communication with a raw oil holding tank.

The finished biodiesel holding tank will normally be located at a lower portion of the end of the container opposite to the power generation means. The compartment located towards the middle of the container, between the compartment containing the power generation means and the compartment containing the finished by a diesel holding tank, will preferably hold the chemical process equipment used to produce the finished biodiesel. According to a particularly preferred embodiment of the present invention, the raw oil from the oil expeller is preferably pumped into a first heater and then to the mixer where the catalyst is mixed and passes through a second heater, to a settling column. The settling columns preferably allow the methanol vapour to be collected in a holding tank. From the bottom of the settling tank, glycerine is drawn off and discharged to a collection tank external to the machine. The biodiesel is then pumped through further separation steps, at least one of which discharges to a methanol collector, normally to a zeolite column and then to the polishing filters, through a pH meter into the finished biodiesel holding tank. The plant of the present invention includes a power generation means, and the power generation means will normally be mounted at an upper portion of the interior of the container towards one end of the container.

The power generation means will normally include a diesel generating set or diesel power pack. Typically, the power generation means will produce hydraulic power or electricity which will then be used to power the other process components. The power generation means is preferably fully enclosed within a separate compartment within the container. This may assist with limiting contamination of the process and/or the raw oil or finished biodiesel.

The power generation means will normally, by its very nature, produce heat during operation. Waste heat from the power generation means may preferably be used to it is partially heat the raw oil or to provide heat to other process equipment.

The power generation means is normally associated with a pump in order to move the raw oil, intermediate products and finished biodiesel into, out of and through the process steps. A screw pump is preferred and normally more than one screw pump will be provided.

The system includes an oil expeller. The oil expeller is designed to pulp the raw feedstock and to produce the raw oil. Any configuration of oil expeller can be used. The preferred oil expeller is adjustable to control the clearance allowed for the feedstock. The adjustable nature of the expeller also allows the control of where by movement of the engaging parts.

The expeller will normally have a central shaft which rotates and about which is mounted a pulping body which engages with a surrounding sheet to grind or pulp with the feedstock to release the raw oil. The expeller shaft is typically driven by an electrical or hydraulic motor powered from the power generation means.

The present invention typically include a raw oil collection tank. Interposed between the outlet of the expeller and the raw oil collection tank is typically a separation or filtration means, normally including a weir and a mesh filter. The raw oil collection tank is typically located below the expeller.

According to a particularly preferred embodiment the tank has a capacity of approximately 600 L. It is of course anticipated that different size tanks may be provided for different sized plants. The raw oil collection tank is preferably vented to the interior of the process area of the container by means of a circuitous vent member. This vent member will typically be provided with a flash arrestor, normally a gauze flash arrestor. Normally, the circuitous vent member will rise to a level above the interior floor of the container, normally to a height of approximately 300 mm above the floor. The raw oil will typically be extracted from the raw oil holding tank by a pump means. Normally, the raw oil outlet from the raw oil collection tank will be located above the base of the tank, a preferred position being approximately 50 mm above the base of the tank. Normally, the raw oil collection tank will also have a drain valve positioned at a lower portion in order to permit removal of condensation or to allow the tank to be drained.

Upon leaving the raw oil collection tank, the oil will typically be passed through a heater, normally a heat exchanger. The heat exchanger will normally be located immediately adjacent the discharge side of the pump. The heat exchanger will preferably supply enough energy to the oil to raise the raw oil temperature to approximately 45°C.

The heat will normally be provided from heated water which may be heated by diverting the flow of coolant from the power generation means .

The catalyst used in transesterification process of the present invention will also be stored within the container of the preferred embodiment. Normally, the catalyst will be stored in one or more catalyst tanks. These tanks are preferably able to be filled from outside the container and normally, an inlet will be provided for this purpose. The catalyst tanks will also preferably be ventilated by providing a circuitous vent member again typically with an associated spark arrestor. The catalyst and the raw oil will normally be mixed in the mixer after heating the raw oil. The catalyst used normally be an anhydrous mixture of the methanol and sodium or potassium hydroxide in proportions of approximately 12:1 by mass, for example Sodium Methylate. This mixture will normally be injected into a disturbed flow of raw oil in the mixer by means of a dosing pump. The mixer will preferably be appropriate configured to thoroughly mix the catalyst and raw oil.

A further heater will typically be provided immediately adjacent to mixer such that the fluid exiting the mixer can be heated to approximately 9O⁰C. Again, the heater will normally utilise waste heat recovered from the power generation means by means of hot air derived from passing a current of air across the exhaust pipe. An additional benefit of using the waste heat is the cooling of the exhaust from the power generation means (to approximately 15O⁰C.)

The mixer may have integrated heating means provided to maintain the heat of the mixture whilst in the mixer. This can be achieved by wrapping the mixer in a heated water j acket, for example.

As the temperature of the mixture is raised progressively above 60°C, the methanol gases vaporise off the mixture in a controlled fashion. This gas will typically be condensed and collected in a vessel connected to an anti- siphon/degassing column. Removing the gas at this process location will preferably permit all subsequent process vessels to be gas tight.

There will normally be at least one separation means to separate the methyl ester from the other materials present in the reaction mixture. The separation steps will normally include degassing, settling and glycerine separation, final methanol separation, filtration, and final polishing. The settling and glycerine separation step will preferably include the removal of the methyl ester, normally by drawing off, and the discharge of the glycerine from the product mixture to an external collection vessel. The methyl ester is preferably drawn off to a flow stabilising column for the final methanol separation process. The final methanol/methyl ester separation will preferably take place in a methanol separator. The methanol separation of will preferably be a mechanical device that allows the methanol to flash vaporise from the product mixture by using differential pressure rather than heat. The methanol is preferably driven by airflow to a condensation column and from there to a collection vessel.

The methyl ester is preferably collected within the methanol separator and passed to the flow stabilisation column where it joins the methyl ester which was separated from the settling and glycerine separation step.

The methyl ester is then preferably moved via the pump means through the filtration and polishing steps. The methyl ester is preferably passed through a series of filters of ever decreasing cross-section to provide a preferable ultimate filtration size of approximately 1 micron. The methyl ester may also be pumped through a zeolite column and/or an activated carbon column to adsorb remaining contaminants.

A pH adjustment system may be provided to ensure that the product biodiesel has a pH of approximately 7. The adjustment system may be configured to add amounts of sulphuric acid in order to comply with the requisite European standard.

Following the above steps, the biodiesel fuel is then preferably discharged into the biodiesel holding tank. According to be particularly preferred embodiment, the holding tank is approximately 2000 (m)litres in capacity and is located in a lower portion of the container. Typically, the ventilation will be provided for the holding tank by circuitous vent again, provided with spark arrestors and extending to approximately 300 mm above the top of the holding tank.

The plant of the present invention is typically provided with a comprehensive hydraulic control system. Typically, all the hydraulic or electrical motors provided and driven by the power generation means will be located outside the process area. Control wiring and valve operated servos are preferably low voltage with the wiring being shielded and communicating with a control panel through a gas tight gland.

The control panel is preferably also located outside of the process area. The feedstock used according to the present invention can include most oil bearing fruit or plants for example, jatropha, palm, rapeseed, and the like. Other feedstocks can be used with an appropriate adjustment of the process conditions or parameters.

Brief Description of the Drawings. Various embodiments of the invention will be described -with reference to the following drawings, in which:

Figure 1 is a schematic of a general transesterification reaction used in the system of a preferred embodiment of the present invention. Figure 2 is a view from above (top wall removed) of a particularly preferred configuration of the container of the present invention.

Figure 3 is a perspective view from above of the container illustrated in Figure 2.

Figure 4 is an isometric view of the container illustrated in Figures 2 and 3.

Detailed Description of the Preferred Embodiment. According to a particularly preferred embodiment, a portable biodiesel manufacturing plant 10 is provided. According to the preferred embodiment, the system has the following features: Generating Set or Power Plant

The proposed generating set is the Kubota SQ-3200, with operating parameters of: • Engine Speed: 1500 rpm

Power : 2OkVA

Voltage: 415 volt

Phase: 3 phase

Generator: 4 pole

Insulation: Class H

*ine is a Kubota V2203-EBG with the following dimensions:

Design: 4 cylinder in line, 4 stroke cycle, water cooled

Injection Indirect

Bore: 87 mm

Stroke: 92.4 mm

Displacement: 2,197 cc

The generating set is fully enclosed, with a sound footprint meeting all current legislation and is contained in an upper part 11 of one end of the container of the illustrated embodiment. The characteristics are as follows: • Consumption 5.3 litres per hour • Fuel tank 62 litres

• Starting Electric

• L x W x H 1,675 x 780 x 970 mm

• Weight 730 kgs • Sound level 63 dB (A)

In addition to the standard generating set, coolant from the jacket cooling system will be passed via a thermostat to a heater around the oil system.

Around the exhaust system, a heat recovery system is mounted to provide further heating of the raw oil. At the front of the engine, two B-form pulleys will each drive a Mono screw type pump through an electrically operated clutch. Each pump will be regulated to handle flow rates of approximately 250 litres per hour.

Power is provided by a diesel powered hydraulic power pack. The engine water cooled high speed diesel engine running at approximately 2600 rpm. Power is generated by a bank of three hydraulic pumps providing power to:

o the process pumps o the expeller motor o the electrical alternator The electrical alternator is sized to meet the requirement of the three heating elements (15kW) and driven by a hydraulic motor running at 1500 rpm.

To accommodate the increase in electrical current arising from the fluctuation of hydraulic motor speed, a consequence of the viscosity degradation due to the heat build up in the hydraulic oil, the alternator is specified to a low temperature rise (4O⁰C). There is also a hydraulic oil cooling matrix mounted outside the engine radiator.

The electrical system comprises a simple distribution board with a three phase isolator, an isolating switch and the thermostat contactor.

The air flow to the radiator is partially deflected to provide a flow that permits the necessary pressure differential that will draw air through the Chantrelle.

The raw material feedstock will typically undergo breakdown in physical size and/or chemical availability of the target material. A "squidger" may be used initially. The squidger is an adaptation of the wood chipping machine used extensively to render down trees to more easily disposed wood drippings. The squidger is hydraulically powered and turns a circular plate fitted with cutting blades, and is enclosed in a sheet metal housing.

The material exiting the squidger may then proceed through a macerator. The purpose of the macerator is to crack the feedstock in order to permit the expeller to expend less energy in cracking the feedstock and thereby use its energy more efficiently in expelling the oil.

The macerator preferably comprises a pair of intermeshed gears mounted between face plates. One gear, the driven gear is located in bush type bearings mounted as friction fit in the end plates. The gear is driven by a hydraulic motor by way of a reduction gear arrangement that permits the macerator gears to run at half the motor speed.

The macerator gears are typically hardened steel and are sufficiently long to cover the whole width of the expeller intake. The idler gear will normally be mounted in similar bush bearings as the driven gear, however, the bushes are mounted in an adjustable sliding block in each face plate in order to permit the distance between the gear axes to be adjusted.

The side face plates are preferably secured to two plates parallel to the axes of rotation. Above the sides, there is normally a tapered chute arrangement to accept the loaded feedstock. Under the macerator, there is a sheet metal chute to guide the broken feedstock to the expeller. Expeller

The purpose of the Expeller is to extract the oil from within the feedstock.

The Expeller' s has a tapered screw arrangement. It is driven by a hydraulic motor through a flexible direct coupling and an adjustable positive pressure device.

The shaft speed is controlled by a speed controller on the hydraulic motor which is constrained to operate in the range 0 - 120 rpm.

The shaft comprises two sections, a parallel section that provides a positive feed, and a tapered section that permits a controlled compression of the feedstock. The shaft is a composite structure of glass filled nylon laid upon a steel shaft.

The shaft rotates within a tapered bore, machined in a series of plates bound together by an array of tie rods in high tensile steel.

At the discharge end of the Expeller, the shaft discharges the compressed feedstock into a choke arrangement that is adjustable to permit a variation in throughput that has a resultant controlling influence on the pressure within the expeller.

The plates have clearance channels to relieve the oil. The oil is discharged into the hot oil tank. Hot Oil Collection Tank

After passing through a weir and a mesh filter, the clear oil is collected in a plastic tank mounted below the expeller 12. The tank has a capacity of approximately 600 litres. The tank is vented to the interior of the process area by means of a goose necked vent with a gauze flash arrestor. The goose neck will stand 300 mm above the floor.

Oil will be extracted from the tank by a Mono pump, drawing by way of fuel grade flexible hoses from approximately 50 mm above the base of the tank. The tank will have a drain valve positioned at the bottom to permit condensation to be run off. Primary Oil Heater

The oil will be passed through a marine type heat exchanger within the generating set immediately upon discharging from the pump. This heat exchanger will supply approximately 5kW of energy to the oil raising the oil temperature to approximately 45°C. Heat from the jacket water will be provided by diverting the flow of coolant between the radiator and the engine water jacket by means of a tee- piece and a thermostat, consistent with marine practice. Catalyst Tank

The catalyst tank 17 is an intrinsic part of the separating bulkhead and holds 300 litres of premixed catalyst. The tank is filled from the exterior of the plant of the present invention by hand pump from 200 litre drums, and ventilated by a swan necked vent with spark arrestor. Mixer

The oil is supplied to the mixer from the Primary Oil Heater. In the mixer the catalyst, a mixture of Methanol and Sodium or Potassium Hydroxide in the proportions of 12:1 by mass, is injected into a disturbed flow of raw oil by means of a dosing pump supplied by Prominent Fluid Controls Ltd. Within the mixer, there is an array of wheels, which is another proprietary plant feature that ensures ideal mixing. In an alternative embodiment, the mixer combines the raw vegetable oil with the sodium methylate/methanol reagent.

The flows of the catalyst and raw vegetable oil are controlled to provide the necessary ratio of mixing. The oil enters the mixer at not less than 65°C.

The catalyst enters the mixer by way of a non-return valve. The mixing is achieved through a combination of shear plane and turbulent mixing. Secondary Oil Heater

Upon emerging from the mixer, the fluid is heated to approximately

90°C by means of waste heat recovered from the generator exhaust. The waste heat is collected by heating water in a tube stack by allowing the exhaust gas to pas through the tubes. This has the added advantage of cooling the exhaust to approximately

150°C.

There is approximately 16 kW of available energy in the exhaust.

Heating is achieved by wrapping the mixer in a water jacket. Degassing

As the temperature is raised progressively above 60⁰C, the methanol gasses off in a controlled fashion. This gas is condensed and collected in a vessel connected by hose to an anti-siphon/degassing column, thus permitting all the subsequent vessels to be gas tight. Settling and Glycerine Separation

The settling and separation is undertaken using the HydraShear 13, a patented technology built and developed in Australia by Machining and Hydraulics. This patented system permits the methyl ester to be drawn off and the glycerine to be discharged to an external collection vessel. The methyl ester is drawn off to a flow stabilising column through the final methanol separation process, from which it continues through the remaining polishing and filtration. Final methanol separation The Methanol Separator 14 is a mechanical device that permits the methanol to flash off by using differential pressure rather than heat. The methanol is driven by a draught of air to the condensing column and thence to the collecting vessel. The methyl ester is collected within the separator chamber and passed to the flow stabilising columns 16. Filtration

From the methanol separator, the methyl ester is pumped by the second Mono screw pump through two columns 15 containing zeolite and activated carbon that permits all remaining contaminants to be adsorbed.

In a pre Mixer stage the Zeolite is mixed with Perlite in a proportion that will optimise the absorption of water. In the post-Chantrelle phase, the Zeolite is used without any additive.

The FAME generally leaves the Chantrelle at a pH of 8.5. This is reduced by passing it through the ion exchange medium and subsequently by dosing the FAME with an appropriate quantity of Phosphoric Acid to provide a biodiesel with a pH of 7.0 ⁺/- 0.2, which is well within the desired parameters.

Post neutralisation, the polishing filters are 5μm paper element filters.

The product after this process is biodiesel. Polishing

From the zeolite columns the biodiesel is passed through a series of filters of ever decreasing cross section to provide an ultimate filtration of one micron. Holding Tank

From the holding tank, the biodiesel passes through a pH meter to ensure that the fuel complies with EN 14214, and has a pH of 7. In the unlikely event that it fails so to comply, the fuel will have minute amounts of Sulphuric Acid added to comply.

The neutral fuel is then discharged to a holding tank of approximately 2,000 litres capacity located in the floor of the machine and perforated with large diameter holes.

Ventilation is by swan-necked vents with spark arrestors extending some 300 mm above the tank top. Bonding The structure is generally of a suitable plastic as are all component containers and vessels. Hoses are of fuel grade flexible material with plastic or metal fittings.

AU component elements are grounded by bonding straps to ensure zero resistance, and the whole structure grounded through the container securing anchors. Electrical system

All electric motors are located outside the process area. Control wiring and valve operating servos are low voltage with the cabling shielded and led to the control panel through a gas tight gland. All lights and warning indicators are LED's or LCD's where appropriate. The control panel is located outside the process area. Ventilation

Where possible, natural flow is encouraged. The tanks that comprise the floor of the machine are perforated with large diameter holes to permit heavy gases to sink out of the machine. Vents are located on both sides of the machine at the top in way of the process area.

The container itself will be mounted on legs some 450 mm above a concrete plinth ensuring a natural flow of air under the machine encouraging the circulation of air within the process area. Air from the engine driven cooling fan will be ducted and split to provide the necessary airflow to positively vent the methanol vapours and to provide a positive flow of ventilating air. As this fan is not driven by any electrical device, the risk of spark is eliminated.

In a particularly preferred embodiment, a "cauldron" may be provided to function as both the hot oil tank and glycerin separator.

In essence, it is typically a large oil tank inside which are three heating elements. The oil is heated to HO⁰C, with a lower limit of 100⁰C. The glycerin separation tank is inserted inside the hot oil tank and secured with a collar of angle cross section to provide a gas tight joint. The glycerin separation tank comprises four chambers with a linear reduction in volume across a series of weirs.

The top of the tank is closed by a sealed lid. The bottom of the tank has a manifold that permits the glycerin to be run off as desired. The Container The container is constructed from plastic with securing points accessible only from the interior. Lifting points are located at the four top corners and anchoring points are located at the four lower corners.

The container will be mounted 450mm above the ground with adjusters in the anchor legs to permit the unit to be levelled.

On either side of the expeller, a chute will be situated, on the input side to permit loading and on the opposite side to facilitate discharge.

The engine will be mounted in its sound absorbing container on a mounting platform with rubber infill seals surrounding the unit to provide suitable aesthetics.

The access door will be gas tight with a clear view panel. Access to the container will be by two steps.

The machine is capable of handling most feedstocks currently used. Installation The plant of the present invention requires only the simplest of preparation - level concrete plinth approximately 3 m x 6 m x 150 mm. Road access would assist, but is not essential. Servicing

The servicing regime is minimal, however certain items are essential. • The engine manufacturers recommendations are to be followed rigidly. Oil changes must be undertaken every 250 hors without fail

• The coolant should be blended in accordance with the manufacturer's recommendations

• Filters on the oil feed from the expeller must be cleaned daily • The zeolite column must be cleaned daily, and replaced every 10,000 litres.

• The filter elements in the polishing system must be cleaned every day.

• The oil tank should be drained of any condensation or water prior to starting every morning

• The fuel holding tank should be drained of moisture daily • The expeller shaft should be changed every 1750 hours.

The Process 1. Load feedstock 2. Feedstock macerated a. Through Squidger if Coconut or Macadamia in shell b. Through Macerator

3. Expel oil from feedstock a. Collect oil b. Remove mulch

4. Heat oil

5. Filter oil

6. Mix oil with catalyst 7. Separate glycerine and other by-products from Fatty Acid Methyl Ester

8. Remove excess methanol

9. Filter/ion exchange to reduce pH

10. Neutralisation to bring pH to 7 ⁺/. 0.2

11. Filter to polish 12. Deliver biodiesel

In the present specification and claims (if any), the word "comprising" and its derivatives including "comprises" and "comprise" include each of the stated integers but does not exclude the inclusion of one or more further integers.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

Claims

1. A biodiesel manufacturing plant including a housing containing a power generation means, an oil expeller for mulching raw feedstock to extract raw oil from the feedstock, a mixer/reaction vessel in which the raw oil is mixed with a catalyst material and at least one separation means to separate methyl ester from other products.

2. A biodiesel manufacturing plant as claimed in claim 1 utilising alcoholysis or transesterification.

3. A biodiesel manufacturing plant as claimed in claim 1 or claim 2 wherein the housing is a self-contained shipping container.

4. A biodiesel manufacturing plant as claimed in any one of the preceding claims wherein the container is divided into at least two compartments, the larger being approximately double the size of the smaller, delineating a hazardous area and separating it from a hot area.

5. A biodiesel manufacturing plant as claimed in any one of the preceding claims wherein the housing has at least some ventilation openings but is folly sealable from the environment where required.

6. A biodiesel manufacturing plant as claimed in claim 5 wherein ventilation driven by natural air flows is used by providing openings in a base wall or a lower portion of sidewalls in order to allow the escape of heavier than air gases and lateral openings and events in an upper region in order to allow the escape of lighter than air gases.

7. A biodiesel manufacturing plant as claimed in claim 6 wherein in use, the container is spaced above the mount surface to promote natural flow under the container and circulation within the container.

8. A biodiesel manufacturing plant as claimed in any one of the preceding claims wherein the container is provided with lifting/securing/transport points accessible only from within the container.

9. A biodiesel manufacturing plant as claimed in any one of the preceding claims wherein components of the plant are located within the housing as follows: a. A power generation means is mounted at one end portion of the container; b. an oil expeller is mounted below the power generation means; c. a raw material hopper is located on one lateral side of the container and communicating with the oil expeller; d. a mulch exhaust on the opposite lateral side of the container to the raw material hopper; e. a raw oil catch tray is located below the oil expeller; f. a raw oil holding tank in fluid communication with the raw oil catch tray; g. a finished biodiesel holding tank is located at a lower portion of the end of the container opposite to the power generation means; and h. a compartment located towards the middle of the container, between the power generation means and the finished biodiesel holding tank holding the chemical process equipment used to finish the biodiesel.

10. A biodiesel manufacturing plant as claimed in any one of the preceding claims wherein, the raw oil from an oil expeller is pumped into a first heater and then to a mixer where a catalyst is mixed and passes through a second heater, to a settling column allowing the methanol vapour from the top and from the bottom of the settling tank, glycerine is drawn off, the main process material which is not bottoms or tops is then pumped through further separation steps, at least one of which discharges to a methanol collector, through a pH adjustment step into a finished biodiesel holding tank.

11. A biodiesel manufacturing plant as claimed in any one of the preceding claims including a power generation means fully enclosed within a separate compartment within the housing.

12. A biodiesel manufacturing plant as claimed in claim 11 wherein any waste heat from the power generation means is used to provide heat to other process equipment or streams.

13. A biodiesel manufacturing plant as claimed in any one of the preceding claims including an oil expeller to pulp the raw feedstock and to produce the raw oil through physical liberation of the raw oil.

14. A biodiesel manufacturing plant as claimed in claim 13 including a mixer to mix a catalyst with the raw oil wherein the raw oil is in a receptive condition through heating or disturbance.

15. A biodiesel manufacturing plant as claimed in claim 14 wherein the mixer has integrated heating means provided to maintain the heat of the mixture whilst in the mixer.

16. A biodiesel manufacturing plant as claimed in claim 15 including at least a glycerine separation step and a methanol separation step.

17. A biodiesel manufacturing plant as claimed in claim 16 wherein the glycerine separation step includes the removal of methyl ester and the discharge of glycerine from the product mixture.

18. A biodiesel manufacturing plant as claimed in claim 16 or claim 17 wherein methanol separation takes place in a mechanical device that allows the methanol to flash vaporise from the product mixture by using differential pressure rather than heat.

19. A biodiesel manufacturing plant as claimed in any one of claims 16 to 18 wherein any methyl ester undergoes filtration to provide an ultimate filtration size of approximately 1 micron and polishing to adsorb any remaining contaminants.

20. A biodiesel manufacturing plant as claimed in any one of claims 16 to 19 wherein a pH adjustment system is provided to ensure that the product biodiesel has a pH of approximately 7.