WO2013007394A2

WO2013007394A2 - Mobile biodiesel production system

Info

Publication number: WO2013007394A2
Application number: PCT/EP2012/002965
Authority: WO
Inventors: Thomas RUMMER
Original assignee: Enerdice Gmbh
Priority date: 2011-07-14
Filing date: 2012-07-13
Publication date: 2013-01-17
Also published as: WO2013007394A3

Abstract

Disclosed is a mobile biodiesel production system being transportable by a standard 20' container and a method for producing biodiesel therewith.

Description

MOBILE BIODIESEL PRODUCTION SYSTEM

Field of the Invention The invention relates to a mobile biodiesel production system and a method for producing biodiesel.

Background of the Invention Biodiesel is prepared from oils and/or fats by transesterfication with methanol and the aid of a catalyst to form methyl esters of fatty acids. When the fatty acid methyl esters are sufficiently purified they can be used in unmodified diesel engines.

The requirements for biodiesel, as set forth in the international standard EN 14214, incorporated herein by reference in its entirety, are:

- Completely transesterified product.

- No residual glycerin, catalyst, alcohol and free fatty acids in the product.

- Only traces of water in the product.

- Low sulfur content.

Biodiesel which is produced from rape seed (RME (rape seed methyl ester)) as well as biodiesel which is produced from purely vegetable products (PME (vegetable methyl ester) are specified in the German standard DIN E 51606, incorporated herein by reference in its entirety. Biodiesel which is produced from vegetable and animal oil and fat (fat methyl ester (FME)) is specified in the German standard DIN V 51606, incorporated herein by reference in its entirety.

A great number of diverse processes and production systems for biodiesel have been disclosed. Most of the biodiesel production systems are large industrial manufacturing plants requiring transport of the raw material to their location.

Only few systems have been described which may be transported or relocated. US 6,979,426 B2, incorporated herein by reference in its entirety, discloses a modular biodiesel production unit preferably including a mixing unit, a reactor unit, a separation unit, a distillation unit, and a filtering unit incorporated onto a single platform or onto a housing for ease of relocatability. Other components can be combined therewith to provide a bio-diesel processing plant.

WO 2007/033425 Al , incorporated herein by reference in its entirety, describes a mobile recycling and bio-fuel production system for animal waste comprising a housing integrally formed with or attachable to a vehicle, the housing having an opening for receiving the organic waste; such as meat and fish waste; processing means of a grinding apparatus, enzymatic treatment vat and a centrifuge separator within a rendering facility to separate oil and fats; a bio-fuel production facility (14) for producing a bio-fuel to power the processing means and optionally the vehicle. WO 2009/089591 Al , incorporated herein by reference in its entirety, discloses a biodiesel manufacturing plant including a housing, preferably a container, such as a shipping container, 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. This document does not disclose the structure and the operation mode of the unit wherein the transesterification reaction takes place and glycerin is separated from the product, it only mentions the trade name and the manufacturer thereof.

It was an aim of the present invention to provide a compact biodiesel production system allowing an efficient method of producing biodiesel.

It was a further aim of the invention to accommodate the apparatus for the complete continuous biodiesel process (with the possible exception of storage containers and containers containing chemicals and reagents) in a housing which may be transported at least in a 40' container, preferably in a standard 20' container (length: 6.058 m x width: 2.438 m x height: 2.591 m or 2.895 m). Summary of the Invention

According to a first aspect of the invention, a biodiesel production system comprises a reactor and separator unit (R201) for transesterification of oil into biodiesel, comprising:

- a first chamber (R201-1), which is a transesterification reaction and homogenisation chamber comprising an agitator unit (R 201 -la) and provided with an inlet for oil to be transesterified ,

- a second chamber (R201-2) which is arranged downstream of the first chamber (R201 -1) and is a separator chamber for glycerin settling,

- a third chamber (R201-3) arranged downstream of the second chamber (R201-2) which is a transesterification reaction completing chamber comprising an agitator unit (R 201 -3a) and provided with a device for adding additional catalyst for completing reaction of un-reacted triglycerides,

- a fourth chamber (R201-4) which is arranged downstream of the third chamber (R201 -3) and is a separator chamber for further glycerin settling, and

- a fifth chamber (R201-5) which is which is arranged downstream of the forth chamber (R201-4) and is an outlet chamber provided with an outlet for crude biodiesel,

wherein the first, second, third, fourth and fifth chambers (R201-l ,....R201-5) are provided in a common housing.

A second aspect of the invention is a continuous process of producing biodiesel in the biodiesel system defined above which uses methanol and NaOH as a catalyst to transesterify oil, wherein in the first step the oil is reacted with methanol by mixing with an estimated stoichiometric amount of thereof for transesterifying the oil in the presence of 2 to 10% by weight NaOH catalyst, based on the weight of the methanol, in a first chamber of a reactor, then in a second chamber of the reactor glycerin is separated from the resulting fatty acid methyl ester mixture, which is subsequently reacted for a second time with about 8 to about 15 % of the amount of said mixture containing 2 to 10% by weight NaOH in methanol in a third reaction chamber and wherein then in a fourth chamber of the reactor residual glycerin is separated from the resulting more enriched fatty acid methyl ester mixture, to obtain crude biodiesel, wherein the temperature in the process is about 60°C and the pressure is at or slightly above, e.g. up to about 5% or about 10% or about 15%, based on the absolute pressure, above ambient pressure. According to a third aspect of the invention, a biodiesel production system comprises an oil expeller (EX101) for extracting crude oil from raw feedstock,

a de-gumming process reactor (R101) for removing at least one of gums, metal compounds and other impurities from the crude oil,

a reactor and separator unit (R201) for transesterification of the crude oil to methyl esters and for removing glycerin from the methyl esters,

a mixer (MX202) for adding phosphoric acid for neutralisation of the biodiesel, a blending tank (T205) for completing neutralisation reaction,

wherein the de-gumming process reactor (R101) and the blending tank (TK205) are formed by a first chamber and a second chamber, respectively, of twin chamber vessel

(CV101) which comprises the first and second chambers in a common housing.

According to a fourth aspect of the invention, a biodiesel production system comprises

an oil expeller (EX101) for extracting crude oil from raw feedstock,

a reactor and separator unit or vessel (R201) for transesterification of the crude oil to methyl esters and for removing glycerin from the methyl esters,

a blending tank (T205) for completing neutralisation reaction,

wherein the overall apparatus is designed to be transportable in a standard 20 ft. container and has a rectangular box shape appearance, where the height and width are almost the same and 60% of the overall length, and wherein the apparatus is configured to provide two main areas, one for process equipment and one for standard electrical equipment, divided by a staggered, sealed bulkhead wall (102, 103) spanning across the shorter side of the apparatus approximately l/3rd along the length of the apparatus, wherein the shorter main area houses the process equipment.

Brief Description of the Drawings In the following, embodiments of the invention shall be described with reference to the drawings, in which:

Fig. 1 shows a reactor and separator unit according to embodiments of the invention; Fig. 2 is a perspective view of a biodiesel production system according to embodiments of the invention;

Fig. 3 is another perspective view of a biodiesel production system according to embodiments of the invention;

Fig. 4 is still another perspective view of a biodiesel production system according to embodiments of the invention showing a pump module; Fig. 5 is a perspective view of a twin chamber combination vessel according to embodiments of the invention;

Fig. 6 is a perspective view of a crude oil tank according to embodiments of the invention; Fig. 7 is a perspective view of a buffer tank according to embodiments of the invention; Figs. 8 and 8a show process diagrams of embodiments of the invention; Fig. 9 is a reaction scheme of the transesterification reaction in biodiesel production.

Detailed Description

The process of transesterification of purified plant oil to produce biodiesel conducted in the biodiesel production system of the present invention is a continuous process comprising transesterification of purified plant oil with methanol aided by a catalyst to obtain a mixture of fatty acid methyl esters (biodiesel) and glycerin (or glycerol) (this reaction is depicted in Fig. 9), which is separated from the biodiesel, and neutralization and purification of the latter.

The continuous transesterification process according to an aspect of the invention which is conducted in reactor and separator unit of the biodiesel production system according to the first aspect of the present invention uses methanol as the transesterification agent. It is a two- step procedure catalyzed by NaOH. The process is described in further detail below. In other aspects of the invention, any type of catalysis, such as alkali, acid or enzymatic catalysis, and procedure, such as a one-step or two-step procedure, known in the art for transesterification of oils and fats with methanol, and any transesterification process equipment suitable for a continuous process mode including separation of glycerin and, as the case may be, methanol may be used.

In some embodiments of these other aspects, the transesterification process is a one-step or two-step procedure catalyzed by NaOH conducted in any suitable equipment. The reactor and separator unit according to the first aspect of the invention is designed such that the transesterification reaction proceeds in two separate stages, with settling of products after each reaction stage. After a first stage glycerin is continuously withdrawn from the bottom phase, while after a second stage glycerin is intermittently withdrawn. All glycerin may be flowed by gravity into an external collection tank.

The catalyst used is NaOH, which may be mixed into an external catalyst tank. The methyl ester product may be pumped out of the reactor to be processed for methanol removal, and then to the final biodiesel purification. It should be mentioned that during the reaction/separation stages in the reactor and separator unit (or cauldron) typically methanol is dissolved in both the glycerin and methyl ester phases. The methanol in the glycerin phase can be collected externally to the system, but this is not a subject matter of the present invention. The methanol in the methyl ester phase may be separated in a flash tank, recovered in a separate methanol collection tank, and later recycled back into the external catalyst tank.

The process may further be preceded by (a) prior step(s) of

- extracting crude oil from a plant material, removing impurities therefrom and collecting the purified oil in a buffer/collection tank;

in which case only purified oil is transesterified in the transesterification step(s) described above.

The process including both of the above-described parts of the process (transesterification and extraction/purification of crude oil) will be named hereinafter "continuous biodiesel production process", the process describing only the transesterification and neutralization and purification step(s) will be named "continuous transesterification process". The part of the biodiesel production process which comprises extraction of crude oil, removal of impurities and collection of the purified oil will be named "extraction process". The total of the se process will be named "complete biodiesel production process (or apparatus)".

According to the first aspect of the invention a biodiesel production system comprises

- a first chamber, which is a transesterification reaction and homogenisation chamber comprising an agitator unit and provided with an inlet for oil to be transesterified;

- a second chamber which is arranged downstream of the first chamber and is a separator chamber for glycerin settling; the second chamber may include a coalescer for enhancing separation of glycerin from crude biodiesel and is provided with a drainage outlet at the bottom of the chamber for removing glycerin and other substances which are heavier than the crude biodiesel from the reactor and separator unit, and with a skimmer which is arranged near the top of the chamber to remove soaps and/or emulsions lighter than the crude biodiesel;

- a third chamber arranged downstream of the second chamber which is a transesterification reaction completing chamber comprising an agitator unit and provided with a device for adding additional catalyst for completing reaction of un-reacted triglycerides,

- a fourth chamber which is arranged downstream of the third chamber and is a separator chamber for further glycerin settling; the fourth chamber may include a coalescer for enhancing separation of glycerin from crude biodiesel and is provided with a drainage outlet at the bottom of the chamber for removing glycerin and other substances which are heavier than the crude biodiesel from the reactor and separator unit, and with a skimmer which is arranged near the top of the chamber to remove soaps and/or emulsions lighter than the crude biodiesel, and

- a fifth chamber which is which is arranged downstream of the forth chamber and is an outlet chamber provided with an outlet for crude biodiesel,

wherein the first, second, third, fourth and fifth chambers are provided in a common housing. In some embodiments, the first chamber of the reactor and separator unit is arranged at one end of the same with respect to its longitudinal direction, and the third chamber is arranged at the other, opposite end of the reactor and separator unit with respect to its longitudinal direction, the second and fourth chambers are arranged between the first chamber and third chamber in an intermediate portion of the reactor and separator unit, and the fifth chamber is arranged within the first chamber and adjacent to the fourth chamber.

In some embodiments, a part the first chamber extends over the whole width of the reactor and separator unit, the third chamber extends over the whole width of the reactor and separator unit, the second chamber and the fourth chamber are arranged side-by-side, wherein the combined widths of the second and fourth chambers correspond to the whole width of the reactor and separator unit and the fifth chamber is arranged within the first chamber and adjacent to the fourth chamber and having a width corresponding approximately to the width of the fourth chamber.

Generally, the flow through the reactor and the separator unit is in the longitudinal direction thereof from the first chamber to the second chamber and from the second chamber to the third chamber and then in the opposite direction back to the fourth chamber and from there back into the fifth chamber, the flows in the second and forth chambers being in the same direction.

After completion of the transesterification procedure, the crude biodiesel is usually purified further.

A wide variety of refining procedures for biodiesel are known, partly dependent on the transesterification procedure employed. In some embodiments, all of them can be used, as long as they conform to the transesterification procedure employed and lend themselves to a continuous process mode.

When a NaOH catalyzed transesterification procedure has been implemented, the process equipment for the further purification of the crude biodiesel, through which the crude biodiesel is passed, may comprise the following in the given order of passage of the crude biodiesel:

a flash tank, wherein hot methanol which had been heated on the way from the reactor and separator unit is evaporated (optionally by the aid of a vacuum) and leaves through the top of the tank to be condensed in a buffer tank;

a static mixer for adding phosphoric acid for neutralisation of the biodiesel; a blending tank for completing neutralisation reaction, which may be the upper chamber of the twin chamber combination vessel described with reference to Fig. 5, an ion exchange purification vessel, where residual glycerin, soaps, free fatty acids, un-reacted oil, waxes, salts, water and methanol are removed,

- a water separator, and finally

a polishing filter, to remove any remaining particulate impurities,

from where the biodiesel exits the system to an external collection tank.

The biodiesel production system of the first aspect as well as the third and fourth aspect of the present invention may further comprising an oil expeller for extracting crude oil from raw feedstock, a crude oil tank for collecting crude oil from the expeller, a de-gumming process reactor for removing at least one of particulate impurities, gums, metal compounds and other impurities from the crude oil, a centrifuge, and a buffer tank for holding oil which is fed to the reactor and separator unit. Oil expellers are well-known to the average person skilled in the art. The oil expeller which may be part of the biodiesel production apparatus or system of the invention may be any compact commercially available oil expeller.

The raw feedstock is selected from a plant or vegetable material, preferably, but without being limited thereto, rape seed, copra, and jatropha.

The oil expeller normally includes a heated dosing screw which receives the raw feedstock from an external source, e.g. from a hopper. A hydraulic motor drives the internal screw and feeds directly into the expeller. A hydraulic radial piston motor mounted directly onto the expeller may drive the expeller's internal tapered compacting screw which compacts the feed stock in the heated headstock of the expeller extracting of the residual oil in the feedstock.

In preferred embodiments, the extracted crude oil then drops through an open cavity in the bottom of the expeller and through the opening in the top surface of a crude oil buffer tank which collects the crude vegetable oil. The husk/waste matter from the expelling process is ejected from the expeller and may slide down the shoot provided by the design of the top/side walls of a preferably provided buffer tank, as shown in Fig. 4, for external collection. The preferred crude oil buffer tank has a double walled design the cavity of which is filled with the coolant of the power generator set (Gen Set) (both described hereinafter) to maintain a temperature of 60-65° C of the process oil. The level and temperature of the liquid is monitored and controlled using integral instrumentation.

The preferred crude oil buffer tank is a vessel having a rectangular shape with a flat bottom to allow that the crude vegetable oil is agitated sufficiently so as to ensure an even distribution of impurities and sediment. There is an internal tube with holes/nozzles located along its length, through which re-circulated crude vegetable oil is fed by means of a pump mounted to the tank assembly. There exists various methods and associated process equipment parts suitable for removing the impurities from the extracted crude oil in a biodiesel producing process using alkali catalysts, see , e.g. the above-cited US 6,979,426 B2, WO 2007/033425 Al , and WO

2009/089591 Al . All of these methods and process equipment parts may be used in the present invention as long as they are suitable to be used together with alkali catalysis.

In preferred embodiments of the invention, the removal of the impurities in the crude oil involves passing the crude oil through a filter, adding phosphoric acid (e.g. 75% by wt., technical grade) and mixing the mixture in a static mixer to precipitate gums, metal compounds and other impurities, then adding water to the crude oil stream via a tee or a mixer and conditioning the process oil/acid/ water combination in a de-gumming process reactor for completing hydration and agglomeration and formation of large gum particles, which are then removed together with the other particulate impurities in a centrifuge. The amount of gums depends on the quality and type of oil. Gums contain non-hydratable phosphatides (NHP) and hydratable phosphatides (HP) which have been hydrated by the previous addition of acid and precipitate from the crude oil when water is added.

The de-gumming process reactor provides for a controlled specific agitation from a suitably designed impeller specifically selected to create an equivalent residence time of 30 minutes based on the shaft speed to allow the conditioning process to take place. The de-gumming process reactor may be part of a combination twin vessel wherein the de-gumming process reactor and the blending tank are formed by a first chamber and a second chamber, respectively, of the twin chamber vessel which comprises the first and second chambers in a common housing. The twin chamber vessel may be provided with a mixing unit for agitating the content of the first and second chambers including a mixing motor, a common shaft rotatably driven by the mixing motor and passing at least partially into each of the first and second chambers of the twin vessel and a first stirring element and a second stirring element, each being fixed to the rotatably driven common shaft and arranged in one of the first and second chambers, respectively.

The conditioned process oil may now be pumped into a centrifuge where the particulate impurities are removed. From there, the purified process oil, which, however, still contains water, is fed into a process oil buffer/collection tank which is described in detail hereinafter with reference to Fig. 7, preferably by gravity feeding so as to obviate the necessity for a pump and concomitant energy costs.

Before entering the equipment for the continuous transesterification procedure, any purified process oil will be pumped through a water separator.

A power generator set (hereinafter: Gen Set) may provide power to the biodiesel production system. The power generator set (Gen Set) may include an internal combustion engine for providing mechanical power to the oil expeller, and a closed loop fluid circulating system which is a circulating 80% water : 20% ethylene glycol fluid that is conveying heat produced in the generator set.

The closed loop fluid circulating system of the generator set may be coupled to at least two of the reactor and separator unit (which is hold at about 60°C), the buffer tank, the crude oil tank and the twin chamber combination vessel (upper chamber hold at about 70 °C, lower chamber hold at about 60 °C) for transferring heat and holding the same on an elevated temperature approximately (generally in a range of 50-75°C). Used hydraulic fluid may be sent back to the Gen Set. The atmosphere in the biodiesel production system is normal ambient atmosphere.

The closed loop fluid circulating system of the generator set according to the invention reduces energy costs thereof. In preferred embodiments of the invention a pump module comprising at least the majority of and preferably all the process pumps is provided in the centre of the apparatus, which greatly contributes to the compactness of the biodiesel production system.

The material of the part of the equipment which is in contact with the process oil or biodiesel is preferably high-grade stainless steel.

The main and preferred features, individually and also in combination of two or all, by which the compactness of the system can be increased, are the compact integrated reaction and separation chamber of the invention, the arrangement of all pumps in the centre of the system of the invention, and the twin chamber combination vessel of the system of the invention.

In preferred embodiments of the invention, an apparatus comprising the system is designed to be transportable in a standard 20 ft. container and has a rectangular box shape appearance, where the height and width are almost the same and 60% of the overall length, and wherein the apparatus is configured to provide two main areas, the first main area for housing process equipment and the second main area having a length of about 1/5 to about 1/3 of the length of the apparatus for standard electrical equipment the two main areas being divided by a staggered, sealed bulkhead wall.

A highly preferred embodiment of the complete biodiesel production system or apparatus of the invention is described in the following.

In this embodiment, the overall apparatus may have a rectangular box shape appearance, where the height and width are almost the same and approximately 60%, more general about 50% to 75% of the overall length.

The apparatus may be configured to provide two main areas, one for process equipment and one for standard electrical equipment, divided by a staggered, also possible a straight, sealed bulkhead wall spanning across the shorter side of the apparatus approximately 1/5 to 1/3 of the length, more general 30% to 45% of the length of the apparatus. The shorter main area may house the standard electrical equipment, and the longer main area may house the process equipment. However, it is not excluded the opposite. Also, both main areas might have the same length. The twin chamber vessel may be located centrally along the height of the apparatus near an external side / wall of the apparatus,

The two-phase reaction and separation unit may be situated above the expeller across essentially the full width of the apparatus.

Housed in the centre of the apparatus may be a pump module that contains all or at least a part of the process pumps, rather than as in-lined arrangement.

The apparatus may be constructed from aluminum extruded profiles and covered with a laminated paneled door system, the apparatus equipment is housed within and upon the main structure as well as upon additional extruded beams located within and connected to the main structure, and the apparatus is designed to be transportable in a standard 20 ft. container, wherein provisions for above/crane lifting as well as forklift lifting are provided within the structure.

A rotating tubular feeding screw system may be located directly above of the expeller press, for feeding of the same, wherein the feeding screw is provided to be stored during transport, swung through 90 degrees to enable attachment to external feeding device, and anchored to main frame during use.

The expeller press may be located low in the apparatus yet above the crude oil collector tank to enable gravity feed of extracted oil, i.e. the crude oil collector tank may be located underneath the expeller press. The centrifuge may be located approximately 60 to 105 cm above the apparatus floor and situated above the collection tank to enable gravity feed of process oil, and adjacent to twin phase vessel and on an external side / wall to allow easy access from outside for cleaning and for collection of waste products at an external connection, with water separators are located centrally inside the apparatus with level meters visible from the monitoring/work area. The two-phase reaction and separation unit or vessel may be situated above the expeller across essentially the full width of the apparatus, and the Gen Set may be located on the side opposite of the crude oil collection tank across essentially the whole width of the apparatus.

A control box for controlling apparatus and Gen Set functions may be situated above the Gen Set.

The de-gumming process reactor and the blending tank may be formed by a first chamber and a second chamber, respectively, of a twin chamber vessel which comprises the first and second chambers in a common housing.

A continuous process of producing biodiesel in the biodiesel production system of the first aspect of the invention uses methanol and NaOH as a catalyst to transesterify oil, wherein in the first step the oil is reacted with methanol (MeOH) by mixing with an estimated stoichiometric amount thereof for transesterifying the oil in the presence of 2 to 10% by weight NaOH catalyst, based on the weight of the methanol, in a first chamber of a reactor, then after transport into a second chamber of the reactor glycerin is separated from the resulting fatty acid methyl ester mixture, which is subsequently reacted for a second time with about 8 to about 15 % of the amount of said mixture containing 2 to 10% by weight NaOH in methanol in a third reaction chamber. In a fourth chamber of the reactor residual glycerin is separated from the resulting more enriched fatty acid methyl ester mixture. The temperature in the process is about 60°C and the pressure is at or slightly above, e.g. up to about 5% or about 10% or about 15%, based on the absolute pressure, above ambient pressure.

Following completion of the transesterification reaction, the crude biodiesel may be heated to approximately 142°C and then fed into a flash tank. Heating may be accomplished in two stages. Firstly, the crude biodiesel may exchange heat with the hot biodiesel stream exiting the flash tank. Secondly, if required, an electric heater may heat the crude biodiesel further.

Upon entering the flash tank the methanol vaporizes and leaves through the top of the tank. There it may be condensed and collected in a buffer tank. The condensing medium comes from the chiller. The chilling medium used in the condenser is then used to cool hydraulic fluid from and then circulated back to the chiller. The fluid is sent to the hydraulic header tank for later use.

The flash tank may be operated at reduced pressure. In this case it is connected to a vacuum pump, which allows for lower operation temperature, while still vaporizing methanol out of the methyl ester phase. Inevitably, some of the methanol will remain in the gas phase after the condenser. Therefore, an absorber may be installed as an end-of-pipe waste gas treatment before the gas is sent to the atmosphere.

Collected methanol may be pumped from collection tank to the recovered methanol tank and later pumped back to the external catalyst tank.

The hot biodiesel collected in the flash tank may be utilized as a heat source for the crude biodiesel stream. After being cooled, the biodiesel may be pumped to the neutralization static mixer and into the blending tank.

The biodiesel coming from the flash tank may be neutralized in a static mixer with the addition of phosphoric acid which is usually pumped from external tank. From there, the mixture may be flowed into the blending tank where the neutralization reaction is completed. The flow rate of acid may be regulated by a pH meter installed in the system.

The neutralized biodiesel may be then pumped to a resin bed column, in which almost all of the remaining water is removed. The dried biodiesel may be then pumped to a final water filter and the polishing filter, and may be then collected in an external tank.

The contents of the resin bed may be sent to the external biodiesel collection tank.

The resin bed may be regenerated as follows:

The resin bed may be then flushed with methanol from the external recovered methanol tank using pump. The total flushing volume should be about 660 L or more, and is expected to take 1 hour to complete. The resin bed may be then drained by pumping the methanol left in the bed back to the external catalyst tank. This usually takes about 10 min.

The resin bed after draining residual MeOH may be then circulated with clean biodiesel product to ensure that bed is ready for the next batch of operation. It should be noted that the conditioning phase takes two steps to accomplish. The first step goes through an internal circulation loop (via P208-F203-HEX202-HE201 -FTK201 -TK205, see Fig. 8) using product with higher MeOH content while the second step is an external on-spec product circulation at a higher rate.

The continuous process of producing biodiesel may also include steps preceding the transesterification.

Oil seeds may be fed manually into an extractor. From there crude oil may fall by gravity through a wire mesh into the crude oil tank for temporary storage. A wire mesh may be installed to prevent large solids from entering the crude oil tank. Manual feeding of oil may also be possible through a nozzle at the top of the tank.

The crude oil may be heated, e.g. by hydraulic fluid from the Gen Set circulation line. Also, the crude oil may be continuously circulated, through a pump, back to promote mixing and homogenization of the crude oil.

The preheated oil (at about 50-75°C) in the crude oil tank may be pumped by a crude oil pump to a crude oil filter whereby fine particles are removed from the oil. Depending on the crude oil quality, the oil can either bypass a de-gumming process and be sent directly to the de-gummed oil buffer tank or be sent to a crude oil/H₃P0₄ mixer.

For crude oil with high a phosphatide content (P>10 ppm), phosphoric acid (75% H3P04) that may be stored in an external tank is injected by a pump and intensively contacted with oil in the crude oil/H₃P0₄ mixer to precipitate gums, metal compounds and other impurities.

Acid is usually added to chelate iron, calcium, and magnesium away from the NHP1 complex. Once the iron, calcium, and magnesium are removed from the NHP complex the phosphatide becomes hydratable. This same acid solution may be also used later in the process to neutralize the basic crude biodiesel.

Gums typically contain hydratable phosphatides (HP) and non-hydratable phosphatides (NHP). HP's are those gums which will precipitate from the crude oil when water is added. There may be some phosphorous containing compounds that remain in the oil after water hydration. These materials are referred to as NHP and are removed with acid pre-treatment followed by centrifugation. Both the phosphoric acid and water flow rates may be fixed, as set during commissioning, with manually adjustable valves.

Following mixer water from an external water tank may be pumped into the conditioned oil stream. This water may be used to remove HP's from the crude oil. The crude oil, pre-treated with phosphoric acid and water may be sent to the reactor where the full reaction to remove impurities may be achieved.

From the reactor the mixture may be pumped to a self-discharging centrifuge for product separation.

After passing through the centrifuge, the pre-treated oil may be drain into the de-gummed oil buffer tank by gravity.

After centrifugation, there may be 0.5-1.0% dissolved water in the de-gummed oil stream. To remove this water, an oil/water separator may be installed prior to the cauldron.

From the buffer tank de-gummed oil may be pumped through an oil/water separator and into a cauldron or reactor and separator unit, which may be a multi-stage mixer-settler. Prior to reaching the reactor and separator unit (cauldron), catalyst may be added in-line to the oil stream. The catalyst may be located in an external catalyst tank, and may be pumped to an in-line connection point and to a second mixing stage of the cauldron to ensure high conversion of oil to methyl esters. Before entering the equipment for the continuous transesterification procedure, any purified process oil will be pumped through a water separator.

Preferred embodiments of the invention will now described in connection with the drawings.

Fig. 1 shows the two-stage reaction and separation vessel or unit R201 containing several chambers is a double walled vessel, the enclosed cavity between the walls is to be circulated with coolant pumped from the diesel power unit to maintain the temperature of the liquid within the vessel.

The transfer from one chamber to the next is via transfer pipes and is controlled with descending depths from one chamber to the next. The descending chamber depths are controlled by the height and location of the transfer pipe penetrating a dividing wall. All chambers are separated from any other by way of a fully sealed dividing wall. Chamber R201-1 and R201-3 located at either end of the rectangular shaped vessel, respectively, and are mixing/reaction chambers, both containing an above, lid mounted, motor driven agitator/impeller, equipped with VSD (variable speed drive) and designed specifically for the profile and depth of each chamber and ensuring that equivalent residence times for each stage of the process are met whilst allowing for a continuous feed. Chambers R201-2 and R201 -4 have flow in the same direction and have a sloped bottom in the direction of flow, so they can collect the separated glycerin. Having chamber R201 -2 and R201 -4 flow in the same direction allows the vessel bottom to have a single side view profile. To enable Chamber R201 -2 and R201 -4 to flow in the same direction a longer transfer pipe from Chamber R201-3 to chamber R201-4 is required to move the liquid to the far end of chamber R201-4 rather than through a dividing wall as with all other transfer pipes. Both chambers R201-2 and R201 -4 have installed profiled, full width and height coalescers to aid the separation process in order to achieve the required glycerin separation levels of the process within the specified time and flow rate.

A further chamber R201-5 is the outlet chamber. It usually has a level sensor that allows control of the outlet flow rate. Chamber R201-5 also protects chamber R201-4 from any unwanted turbulence the outlet could cause allowing for an undisturbed separation phase. Chamber R201-3 has an additional feed of catalyst to enable an enhanced reaction. A space is allocated between the liquid level and the lid to allow the evaporated methanol to escape the liquid and occupy this volume where an outlet with a specific mist eliminator is located to draw off and then scrub the methanol from the air before exhausting to the atmosphere.

Chambers R201 -2 and R201 -4 have outlets located at the far end of the chamber in the bottom surface, they are connected with transparent outlet tubes, these are connected through standard pipe work to solenoid valves that are timed to open and close at specified intervals to allow the removal of the separated glycerin from the vessel to an external collection tank. The transparent outlets are for observation and set-up of the timing of the intervals for the solenoid valves.

Chamber R201-2 has located at the far end of the chamber a soap collector, this is effected by having an internal chamber within chamber R201-2 that is set marginally above the liquid transfer pipe, any soap gathering above the baffle height of the internal soap chamber will flow over and into the baffle to be drawn off each day to an external waste tank. The vessel has a combination of a stainless steel fixed, and polycarbonate transparent removable lid. The fixed portion supports the above mounted agitation devices, whilst the removable transparent lid enables observation during commissioning as well as access for maintenance and cleaning of the vessel chambers. Each chamber contains an individual drain allowing for a total drain of the vessel. The reaction and separation unit is hold at about 60°C during operation. The lid of the reaction and separation vessel or unit contains a overpressure valve for relieving methanol in the case the pressure exceeds a certain threshold not far beyond ambient pressure.

With reference to Figs. 2 to 4, now the arrangement of a complete biodiesel production system and its components in one embodiment will be described.

The overall apparatus has a rectangular box shape appearance, where the height and width are almost the same and 60% of the overall length. Whereas the chemical process takes place with two specific and completely separate phases broken into a clearly defined Phase 1 (oil extraction and purification) and Phase 2 (transesterification to and purification of biodiesel), yet the apparatus does not follow this in-line step by step in-line process configuration.

The apparatus is configured to provide two main areas, one for process and one for standard electrical equipment, divided by a staggered, sealed bulkhead wall 102, 103 spanning across the shorter side of the apparatus at approximately 1/5 to 1/3 of the length of the apparatus.

A pump module 5 that contains all the process pumps is housed in the centre of the apparatus rather than in an in-line arrangement. The central location allows for distribution of the process liquids while maintaining short line lengths between pumps 5 and equipment but still allowing for a partially plumbed module to be completed off-line in the assembly process and a compact space efficient design within the apparatus.

The apparatus is constructed from aluminum extruded profiles and covered with a laminated paneled door system. The apparatus equipment is housed within and upon the main structure 100 as well as additional extruded beams located within and connected to the main structure 101. The apparatus is designed to be transportable in a standard 20' container. Provisions for above/crane lifting 101 as well as forklift lifting are provided within the structure. At on-site installation the apparatus is to be set on legs housed within the apparatus during transportation to allow natural airflow around and under apparatus. A floor system comprises wire grids to protect against access from underneath, as well as a flooring grid in the central working/observation area 5, 7 to provide natural air flow through the apparatus. There may be provided a door system which is designed to be fully open during apparatus operation. The door system may hinged along top horizontal edge and hinged to a horizontal position in order to provide shade/shelter to operators, integral supports provided to keep doors in open horizontal position. The door system can be opened to provide natural air flow though complete apparatus. All important equipment is located such to provide access from either, the central work / observation area 5, 7 or the external walls. All additives are located externally, all production including by-products are delivered to external tanks by way of a connection at the apparatus external walls. No additive or final product holding tanks are located within in the apparatus. As shown in Fig. 2, a rotating tubular feeding screw system 1 is located directly above of an expeller press EX101 , for feeding of the same. The feeding screw 1 is stored during transport, swung through 90 degrees to enable attachment to external feeding device and anchored to main frame 100 during use. The expeller press EX101 is located low in the apparatus yet above a crude oil collector tank TK101 to enable gravity feed of extracted oil. The crude oil collector tank TK101 is located underneath the expeller press EX101.

As can be seen from Fig. 3 a self contained partially plumbed pump / solenoid valve module 5 containing all process pumps and additive solenoid valves is located centrally in apparatus. The pump / solenoid valve module 5 located centrally in the apparatus and at the end of the work area gives full access for installation and maintenance with little impact on the rest of the equipment. Particle filters 7 are located near external sides /walls to enable easy access for installation and filter changing. Referring back to Fig. 2, twin chamber vessel CV101 is located centrally along the height of the apparatus near an external side / wall, to enable maintenance of vessel agitating systems without complete vessel removal.

As also shown in Fig. 2, a centrifuge CS101 is located approximately 70 cm above the apparatus floor and situated directly above the collection tank TK201 to enable gravity feed of process oil, also adjacent to twin phase vessel CV101 and on an external side / wall to allow easy access from outside for cleaning and for collection of waste products at an external connection. Water separators are located centrally inside the apparatus with level meters visible from the monitoring/work area 5, 7.

A two-phase reaction and separation unit or vessel R201 is situated above the expeller EX101 across the full width of the apparatus.

As shown in Fig. 4, the a power generator set (Gen Set) GS 101 is located on the side opposite of the crude oil collection tank TK101 directly underneath a control box 13, across the whole width of the apparatus, i.e. the control box 13 is situated directly above the Gen Set GS 101.

A cooling unit 14 of a chiller which is provided for cooling the methanol vapour from the vacuum flash tank FTK201 is located in the direct neighbourhood of the control box 13. Static components which require little regular maintenance are located away from the external sides / walls and in less accessible areas off the central work area 5, 7, these include, but are not limited to heat exchangers, electric heaters, condensing tank, flash tank FTK201 , ion exchange vessel and static mixers.

Heat exchangers are vertically mounted giving all-round clearance to aid function. A condensing tank may be located below the outlet of the feeding heat exchanger to benefit from gravity to continue the flow or cooled/condensed methanol through system to external collection. A partially plumbed motor operated control valve module for methanol recovery process may be located centrally off the work area 5, 7. Main process plumbing utilizing the JIC fitting to give a robust connection with the ability to have equipment changed without compromising the integrity of the connection. In Fig. 5 is shown a vertically arranged twin chamber mixing/conditioning vessel CV101 , sharing a single outer body and single motor MIXl Ola driven centre shaft MIXlOlb. The vessel is divided by a single fully sealed plate R/TK approximately half way up the cylinder to separate the vessel into two chambers, Rl Ol and TK205, the de-gumming process reactor RlOl and the blending tank TK205. The single centre shaft MIXlOlb is provided with two agitator systems, MIXlOlc, MIXl Old, one in each chamber RlOl and TK205, respectively, specifically designed to prepare each phase of the process liquid to meet the process requirements.

The process liquids in each chamber RlOl and TK205 are from different phases of the process baring no similarities. The upper chamber TK205 contains crude biodiesel where in the lower chamber Rl Ol the process liquid is still in the vegetable oil state. The orientation of the chambers is such that if the mechanical seal between the two chambers was to fail and process oil from the top chamber (that of the latter stage of the process) was to enter into the liquid in the lower chamber, no adverse affect would occur on the process and minimum yield would be lost.

The lower chamber RlOl has two strategically located hand holes enabling a single operator to complete all assembly and future maintenance of the lower chamber agitation device. Both upper and lower chambers T 205, Rl Ol have drain facilities, the upper chamber T 205 can be fully drained, this is effected by a vertical tube sealed to the upper chamber TK205 base that drops vertically down before turning 90 degrees to the horizontal position and exiting out of the side wall of the lower chamber. The lower chamber R101 has a nozzle located near the bottom of the vessel for standard drainage. Additional features are included to allow simple and robust installation of, but not limited to, temperature, level, and pressure instrumentation for both upper and lower chambers.

As shown in Fig. 6 a main feedstock oil collection/buffer tank TK101 is a double walled, TK101-2, TK101-3, tank allowing a heated liquid to be pumped through the cavity to heat / maintain the temperature of the liquid housed within, it is provided to house an internally mounted tube TK101-5 submerged in the process oil with specifically located holes/nozzles. The centre tube TK101 -5 is fed by a pump T lOl -l located as part of the tank assembly at one end of the vessel. The centre tube TK101 -5 takes the process oil from the vessel and re-circulates the liquid at a high rate through the same to create a form of agitation that negates the ability for sediment to settle at the bottom of the tank and ensures an even removal of sediment from the feedstock during the normal process procedure, thus removing the need for a more common design of circular tank with a rotary agitation device and cone shaped bottom for regular cleaning or sediment drainage.

One of the walls and the top surface of the vessel has been specifically shaped / designed to integrate with the above mounted expeller EX101 to form a chute TK101 -4 that guides the extracted waste material from the expelling/pressing process to an external conveyor or collection device. The centre tube TK101-5 design does not make necessary additional mechanical agitation devices e.g. a motor driven impeller. The cavity of crude oil tank wall T 101-2, TK101-3 being circulated with and heated coolant directly from the diesel engine of Gen Set GS101 omits the need for additional heating sources, e.g. electrical heaters, thus requiring no additional energy from the Gen Set GS 101 as well as creating a space efficient design. Additional features are included to allow simple and robust installation of, but not limited to, temperature, level, and pressure instrumentation.

Buffer Tank TK201 which is shown in Fig. 7 is a rectangular shaped, double walled, TK 201 - 3, tank with the cavity having an inlet and outlet positioned to allow flow of the engine coolant to circumnavigate the chamber and allow for even distribution and transfer of the heat into the process oil in order of maintaining the temperature of the process oil contained within. It also contains a labyrinth of pipes TK201 -4 in the lower portion of the vessel with an inlet and outlet through the side wall of the vessel.

During the daily maintenance period or other required shut down events, process oil from the conditioning chamber R101 of the twin combination vessel CV101 can be pumped through these pipes with the purpose of absorbing heat from the process oil contained within, to enable the conditioning phase to continue without loss of temperature, removing the need for additional heating sources e.g. an electrical heater that take further power consumption from the Gen Set 101 as well as causing additional cost weight and packaging issues.

Referring now especially to the diagrams of Figs. 8 and 8a, a description of a highly preferred process embodiment will be given.

Feedstock, generally, rape seed, copra, jatropha, but not limited to is fed to a heated dosing screw from an external source, e.g. from a. hopper, as shown by the arrow. A hydraulic motor RM101 drives the internal screw and feeds directly into the expeller EX101. The hydraulic radial piston motor RM101 mounted directly on the expeller drives the expeller internal tapered compacting screw which compacts the feed stock in the heated headstock of the expeller, extracting of the residual oil in the feedstock. The extracted oil then drops through the open cavity in the bottom of the expeller and through the opening in the top surface of Buffer Tank T 101. The husk/waste matter from the expelling process is ejected from the expeller and slides down the shoot provided by the design of the top/side walls of the buffer tank, for external collection.

Buffer Tank TK101 collects the crude vegetable oil and has a double walled design where the cavity is filled with the Gen Set GS 101 coolant and maintains a temperature of the process oil of 60-65°C. The level and temperature of the liquid is monitored and controlled using integral instrumentation.

Buffer Tank TK101 is a rectangular shaped vessel with a flat bottom to ensure that the crude vegetable oil is agitated sufficiently to provide for an even distribution of impurities and sediment. There is an internal tube with holes/nozzles located along its length which is fed by re-circulated crude vegetable oil through a pump mounted to Tank assembly TK101.

When the crude vegetable oil reaches the required level in the buffer tank T 101 A, pump PI 01 which is located on a pump module 5 in the centre area of the apparatus and, pumps the oil through the a heat exchanger HEX102, then through the particle filter F101 and into a static mixer MX101.

As the main stream passes through the static mixer MX101 , phosphoric acid (75% H₃P0₄, TG) is added from an external tank T 102 and mixed through the static mixer MX101. The purpose of this additive is to precipitate gums, metal compounds and other impurities. Acid is added to chelate iron, calcium, and magnesium away from the NHP complex. Once the iron, calcium, and magnesium are removed from the NHP complex, the phosphatide becomes hydratable.

The phosphoric acid is pumped into the main stream from an external source using pump PI 02, with its flow controlled to match with the main process flow rate. It is controlled in two specific flow rates using an oversupply and recirculation design on plumbing and flow control valves set to achieve flow rate requirements.

Prior to entry into the de-gumming process reactor or conditioning tank R101 which is the lower chamber in a combination twin vessel CV101 (which also includes a blending tank TK205 which will be described later, and which is, for the sake of better understanding, shown two times in the Fig. 8) water is added into the main stream at a controlled rate via a tee, or a mixer MX102, in the main line. This water addition enhances hydration,

agglomeration and formation of large gum particles. Similarly, the amount of warm water depends on experience and type of oil and quality for efficient agglomeration.

The water is pumped into the main stream from an external source using pump PI 03, with its flow controlled to match with the main process flow rate. It is controlled in two specific flow rates using an oversupply and recirculation design on plumbing and flow control valves set to achieve flow rate requirements. To ensure that there is no emulsification of the additive water being fed from and external tank and the process oil due to differing temperatures, the water passes through a heat exchanger that is positioned in the process oil line from the original collection tank TK101 and prior to the first process pump PI 01. Due to the very low flow rate of the water additive the heat taken from the original process oil is minimal and thus does not affect the process.

The process oil/acid/water combination is conditioned in the combination vessel by means of a controlled specific agitation from a suitably designed impeller. Due to the single shaft design within the Combination Vessel the impeller has been specifically selected to create an equivalent residence time of 30 minutes based on the shaft speed to allow the conditioning process to take place. The amount of phosphatides/gums depends on the quality and type of oil. Gums contain hydratable phosphatides (HP) and nonhydratable phosphatides (NHP). HP's are those gums which will precipitate from the crude oil when water is added. Pump PI 06 pumps the now conditioned process oil into the centrifuge CS101 where the phospholipids, gums, metal compounds and other impurities are removed and the process oil is gravity fed from the centrifuge into the buffer/collection tank TK201 positioned directly below, removing the need for an additional pump and thus reducing the apparatus' overall power consumption and minimizing space used.

A buffer tank TK201 has a double walled construction with the cavity being circulated with coolant from the running diesel engine. This serves to maintain the temperature of the conditioned vegetable oil held within the buffer tank. The level and temperature of the liquid is monitored and controlled using the integral instrumentation. As it is shown in Fig. 8a, the power generator set (Gen Set) GS101 which includes an internal combustion engine for providing mechanical power to the oil expeller EX101 has a closed loop fluid circulating system which is circulating fluid that is conveying heat produced in the generator set GS 101. The closed loop fluid circulating system of the generator set GS 101 is coupled to the reactor and separator unit R201 , to the buffer tank TK201 and to the crude oil tank TK101 for transferring heat and holding the same on an elevated temperature.

Reverting to Fig. 8, a pump P201 is provided to take the process oil from the buffer tank TK201 and pumps it through a water separator F202. After exiting the water separator F202 the process oil is mixed in-line with a catalyst solution (pre-mixture of sodium hydroxide and methanol / sodium methylate(NaOCH₃) solution) via a tee in the main process line. The NaOH /NaOCH₃ and MeOH catalyst is allocated and controlled in each of the reactors in stoichiometric proportion depending on the requirements at each stage based on the type and quality of oil used. Recycled methanol from regeneration is used in the catalyst solution.

The catalyst is pumped into the main stream using a pump P202 from an external source, with its flow controlled to match with the main process flow rate which is controlled in two specific flow rates using an oversupply and recirculation design in plumbing and flow control valves set to achieve the process flow rate requirements.

The composition continues into a reactor and separator unit R201. In a first chamber 1 , a specifically selected motor driven impeller, matched to the chamber profile and volume ensures that a complete reaction is achieved. The impeller design corresponding to specific rpm ensuring an effective residence time to be achieved which suits the process flow rate and feedstock. During this time, the NaOH-MeOH catalyst mixture with excess MeOH reacts quickly with the neutral oil at a controlled reaction condition, depending on feed oil quality, to homogenize the reactants and minimize mass transfer limitation especially in this first stage reaction. The mixture will pass through a separator chamber 2 to settle most of the glycerin heavy phase and discard it continuously.

A second chamber 2 has a specifically designed coalescer to enhance the phase separation of the transesterification process. It is designed to enable a continuous flow process to achieve the required level of separation of glycerin from the crude biodiesel within a given time based on flow rate. The glycerin being heavier than the process crude biodiesel settles on the bottom of the chamber 2 where it is drained off through the bottom surface outlets. Soaps and emulsions may form on the top and bottom layers during separation. The soaps/un-reacted oil being lighter rise to the surface and are collected for drain off via an (adjustable) pipe opening down to an external collection tank.

The crude biodiesel then travels into a third chamber 3 where additional catalyst is added from external catalyst solution tank T 202 to enhance the reaction phase, and the second reaction takes place to complete reaction of remaining triglyceride un-reacted in chamber 1. The specifically selected impeller corresponding to a specific rpm matched to the chamber profile and volume ensures that the required residence time is achieved to enable the complete reaction to take place. The crude biodiesel then enters a fourth chamber 4, the second phase separation chamber, and with the aid of a specially designed coalescer a second phase of glycerin separation is achieved, once again being drained off intermittently via the bottom surface glycerin outlet.

The process oil now enters chamber 5. This is an outlet chamber that has integral level instrumentation and allows the control of the outlet without any disturbance to the phase separation in chamber 4.

Pump P204 pumps the crude biodiesel through heat exchanger HEX202 where it absorbs heat from the exiting flash tank process oil which raises its temperature prior to entering the electrical heater where the final heating of the crude biodiesel is achieved.

The heated crude biodiesel at specific pressure now enters the vacuum Flash Tank FTK205 through a suitably selected 'Full Cone Tangential Nozzle' for uniform liquid / gaseous fluids distribution, allowing for the specific amount of methanol to be flash evaporated from the crude biodiesel.

After heating and entry into the flash tank FTK201 via a full cone tangential nozzle, the process oil drops down into the collection part of the tank, and the escaped vaporized methanol is drawn up the column by means of the Vacuum Pump VP201. It then exits the column and passes through the heat exchanger HEX201 where it is cooled using the chilled water from the chiller unit C201.

The cooled vapor changes from gas to liquid and via a descending plumbing arrangement the liquid and remaining gas vapor are taken into the condensing tank TK204 where the gas continues by means of the vacuum through the vacuum pump and into a methanol scrubbing / absorbing device.

The liquid methanol collected in TK204 is pumped using P207 from the vessel to a connection point on the apparatus for connection to an external collection device. TK.204 has integral level instrumentation to ensure that a minimum tank volume is maintained to provide for a stable vacuum being maintained in the methanol extraction system.

A further pump P205 then pumps the hot crude biodiesel from the flash tank through the previously mentioned heat exchanger HEX202 and into static mixer MX202 where a stream of phosphoric acid is added to control the pH level of the crude biodiesel.

The phosphoric acid is supplied by the same stream as previously described in Block 1 . The quantity of phosphoric acid is determined by means of analysis of the product in two specific points of the process, one immediately after the mixing through MX202 and the second in a mixing tank TK205 that has a specific impeller to ensure that an equivalent residence time is met to allow the harmonious blending of the acid and product, so as to ensure an accurate dosing and pH control. After mixer MX202 the product continues into the previously mentioned TK205 for blending and, as mentioned, pH analysis.

A pump P208 now pumps the product into the top of the ion exchange purification vessel F203 where on entry the liquid passes through a nozzle liquid distributor. This nozzle ensures that the liquid is dispersed evenly across the cross section of the vessel and evenly over the top layer of the housed resin. The liquid then passes through the resin where residual glycerin, soaps FFA/un-reacted oil/waxes, salts, water and methanol are removed.

The product exits the ion exchange vessel and continues through the water separator F205 to remove additional water to bring the biodiesel water content within specification (e.g. less than 500 ppm) before passing through a so-called polishing filter F206 to remove any remaining particle impurities before exiting the apparatus to an external collection tank.

After the daily production is complete the ion exchange resin requires full regeneration. This process starts with the draining of the ion exchange vessel F203 shown in Fig. 8, and standard process operation to take the occupying process liquid through to the external connection point and into an external collection tank as this process oil is part of the daily biodiesel production. On completion of the 'timed' drainage with the use of a pump and solenoid valve, the drainage of methanol flush stage F203 of the regeneration can begin. This is effected by using pump P209 to pump a required volume of pure clean liquid methanol through the ion exchange vessel F203 within a given time. This 'dirty' liquid methanol is pumped directly into the external catalyst tank where it is blended in to be used as catalyst in the following day's process. The vessel is completely drained by means of a timed process as in the initial drainage to complete the methanol flush phase.

On completion of the methanol flush stage the liquid free ion exchange resin vessel is ready for resin conditioning phase of the resin regeneration process. This is achieved by means of utilizing the apparatus' integral methanol extraction/recovery system, as previously outlined, to remove the excess methanol contained within the ion exchange resin. This phase uses multiple three way solenoid valves to open selected lines within the standard machine equipment, while closing others to create a closed 'loop' through the methanol

extraction/recovery system, TK205 and F203. This loop using the 2 integral process pumps, P205 and P208, cycles the process oil through the methanol extraction system removing high content methanol before passing through the ion exchange resin, thus conditioning the resin by continually absorbing and removing methanol with each pass. After passing the required number of bed volumes of low methanol biodiesel through the resin it is once again in a condition where it can be used for the daily production. The actual required bed volume of low methanol content biodiesel can be checked from time to time via sampling, to check if the methanol content is within required product specification. This may actually reduce the time of regeneration.

The final stage of the resin regeneration process, conditioning phase 2, consist of having a continuous low methanol content biodiesel passed through the resin as in the conditioning phase 1. In this case, however, it is possible to count this production as daily usable product due to its already low methanol content. The product must however be 'blended' with 'in specification' biodiesel to ensure that the combined product meets the methanol content allowable in biodiesel, e.g. to specification EN 14214.

The engine coolant system which is shown in Fig. 8a is provided to incorporate additional plumbing to carry the heated engine coolant to the cavity of three separate vessel/tanks within the 'hot side' of the cooling system. This means that on the exit from the engine rather than passing directly to the cooling pack of the engine the heated coolant is pumped to the cavity of the double walled reaction separator vessel R201 , the block 2 buffer tank TK201 and also the block 1 buffer/collection tank TK.101 in order to utilize the heat so as to maintain the process oil required temperature.

The coolant lines to each vessel / tank are opened and closed with the aid of solenoid valves, and controlled by means of analyzing the temperatures of the process liquids held within the vessel/tanks.

Since the diesel engine of the Gen Set GS101 runs continuously, it is possible to maintain the process oil temperature even during shut down, maintenance and cleaning of process equipment without the need for ramp up times or additional power consuming devices such as electric heaters etc.

In the event the temperatures within the tanks are maintained but the coolant still requires cooling prior to circulation back into the diesel engine the standard cooling pack is in line and able to reduce the coolant temperature as required. During normal operation of the diesel engine, i.e. when the cavities are 'not' being circulated, the diesel engine has its own independent expansion tank. Upon opening of the solenoid valves to the vessel/tanks the cavity within the reactor/separator R201 becomes not only the heating 'jacket' for the liquid within, but also acts as an additional expansion tank for the engine coolant due to the increase in volume of coolant in the system.

Heat exchanger HEX101 is positioned in the hydraulic line and chiller line. The hot side contains the hydraulic fluid on the 'tank' / 'return' line of the radial piston motor and the cold side contains the chilled water from a process chiller. The hydraulic fluid must be cooled prior to circulation through the radial piston motor and it is a requirement to introduce external cooling in order to maintain a small volume header tank. The cooling line however has a dual function.

Heat exchanger HEX 102 is positioned on the outlet line from TK101. The hot side contains process vegetable oil from TK101 while the cold side is that of the additive water from the Block 1 process requirement. The low flow rate / volume of the water enable it to be heated without detrimental effect to the hot side process oil. The temperate in TKlOl will account for the slight temperature loss after the heat exchanging process thus enabling the success of this heat transfer without adverse affects on the process.

Heat exchanger HEX201 is positioned on the outlet of the flash tank FTK201 and the chiller line. The hot side contains the flashed methanol vapor and the cold side the chilled water from the process chiller. This cooling of the methanol vapor is essential in the methanol recovery process.

Heat exchanger HEX202 is positioned on the outlet line of P204 and the outlet line of the flash tank FT 201. The cold side contains the process oil from the reactor/separator unit R201 and the hot side, the heated process oil from the flash tank. The heat transfer within HEX202 is beneficial to both components as it is important to raise the temperature of the inlet process oil in order to reduce the power consumption of the additional electric heater HE201. On the hot side, however, it is important to reduce to the temperature of the process oil in order to protect the pump P205. This heat transfer therefore meets both requirements making this an essential part of the heat management. During shut down and start up after each day's production it is essential that the temperature of the de-gumming process reactor or conditioning chamber R101 be maintained. This is managed by means of a recirculation line that takes the process oil from the conditioning chamber and cycles it through a labyrinth of pipes running through the lower portion of the TK201. As TK201 is controlled by the constantly running engine coolant, it is possible to maintain the heat of the conditioning chamber process oil without the need for an additional power consuming heating source. This is managed and controlled by means of solenoid valves and integral pumps.

Insulation is utilized on process plumbing lines, tanks and vessels where required to aid in the maintenance of or dissipation of heat in order to meet the process temperature requirements.

Claims

1. A biodiesel production system, comprising a reactor and separator unit (R201 ) for transesterification of oil into biodiesel, comprising:

- a first chamber (R201-1), which is a transesterification reaction and homogenisation chamber comprising an agitator unit (R 201-1 a) and provided with an inlet for oil to be transesterified;

a second chamber (R201-2) which is arranged downstream of the first chamber (R201-1 ) and is a separator chamber for glycerin settling;

- a third chamber (R201 -3) arranged downstream of the second chamber (R201 -2) which is a transesterification reaction completing chamber comprising an agitator unit (R 201 - 3 a) and provided with a device for adding additional catalyst for completing reaction of un- reacted triglycerides;

a fourth chamber (R201 -4) which is arranged downstream of the third chamber (R201 - 3) and is a separator chamber for further glycerin settling; and

a fifth chamber (R201-5) which is which is arranged downstream of the forth chamber (R201-4) and is an outlet chamber provided with an outlet for crude biodiesel,

2. The biodiesel production system as claimed in claim 1, wherein the first chamber (R201-1) of the reactor and separator unit (R201) is arranged at one end thereof with respect to its longitudinal direction, and the third chamber (R201 -3) is arranged at the other, opposite end of the reactor and separator unit (R201 ) with respect to its longitudinal direction, the second and fourth chambers (R201 -2, R201 -4) are arranged between the first chamber (R201 - 1) and third chamber (R201-3) in an intermediate portion of the reactor and separator unit (R201), and the fifth chamber (R201-5) is arranged within the first chamber (R201 -1) and adjacent to the fourth chamber (R 201-4).

3. The biodiesel production system as claimed in claim 1 or 2, wherein a part of the first chamber (R201 -1) extends over the whole width of the reactor and separator unit (R201), the third chamber (R201-3) extends over the whole width of the reactor and separator unit (R201), the second chamber (R201-2) and the fourth chamber (R201-4) are arranged side-by- side the combined widths of the second and fourth chambers (R201-2, R201 -4) spanning the whole width of the reactor and separator unit (R201), and the fifth chamber (R201-5) is arranged within the first chamber (R201-1) and adjacent to the fourth chamber (R 201 -4) and having a width corresponding essentially to the width of the fourth chamber (R201 -4).

4. The biodiesel production system as claimed any of claims 1 to 3, wherein the flow through the reactor and the separator unit (R201) is in the longitudinal direction of the same from the first chamber (R201-1) to the second chamber (R201-2) and from the second chamber (R201-2) to the third chamber (R201-3) and then in the opposite direction back to the fourth chamber (R201-4) and from there back into the fifth chamber (R201-5), the flows in the second and forth chambers being in the same direction.

5. The biodiesel production system as claimed in any of claims 1 to 4, wherein the second chamber (R201-2) includes a coalescer (R201-2a) for enhancing separation of glycerin from crude biodiesel and is provided with a drainage outlet (R201-2b) at the bottom of the chamber for removing glycerin and other substances which are heavier than the crude biodiesel from the reactor and separator unit (R201), and a skimmer (R201-2c) which is arranged near the top of the chamber to remove soaps and/or emulsions lighter than the crude biodiesel, and/or the fourth chamber (R201-4) includes a coalescer for enhancing separation of glycerin from the crude biodiesel and is provided with a drainage outlet at the bottom of the chamber for removing glycerin and other substances which are heavier than the crude biodiesel from the reactor and separator unit (R201) and a skimmer near the top of the chamber to remove at least one of soaps and emulsions lighter than the crude biodiesel.

6. The biodiesel production system as claimed in any of claims 1 to 5, further comprising a flash tank, wherein hot methanol which had been heated on the way from the reactor and separator unit is evaporated optionally by the aid of a vacuum and leaves through the top of the tank to be condensed in a buffer tank;

a mixer (MX202) for adding phosphoric acid for neutralisation of the biodiesel:

a blending tank (T205) for completing neutralisation reaction,

an ion exchange purification vessel, where residual glycerin, soaps, free fatty acids, unreacted oil, waxes, salts, water and methanol are removed,

- a water separator, and

- a polishing filter, to remove any remaining particulate impurities, from where the biodiesel exits the system to a collection tank.

7. The biodiesel production system as claimed in claim 6, further comprising an oil expeller (EX101) for extracting crude oil from raw feedstock, a crude oil tank (T 101) for collecting crude oil from the expeller (EX101), a de-gumming process reactor (Rl Ol) for removing at least one of particulate impurities, gums, metal compounds and other impurities from the crude oil, a centrifuge (CS 101), and a buffer tank (TK202) for holding oil which is fed to the reactor and separator unit (R201).

8. The biodiesel production system as claimed in claim 7, wherein the de-gumming process reactor (RlOl) and the blending tank (TK205) are formed by a first chamber and a second chamber, respectively, of twin chamber vessel (CVlOl) which comprises the first and second chambers in a common housing.

9. The biodiesel production system as claimed in claim 8, wherein the twin chamber vessel (CVlOl) is provided with a mixing unit (MIX101) for agitating the content of the first and second chambers including a mixing motor (MIXlOla), a common shaft (MIXl Olb) rotatably driven by the mixing motor and passing at least partially into each of the first and second chambers (RlOl , TK205) of the twin vessel (CVlOl) and first (MlXlOlc) and second stirring elements (MIXlOld), each being fixed to the rotatably driven common shaft

(MIXlOlb) and arranged in each of the first and second chambers.

10. The biodiesel production system as claimed in any of claims 1 to 9, further comprising and a power generator set (GS101) for providing power to the biodiesel production system, wherein the power generator set (GS101) includes an internal combustion engine for providing mechanical power to the oil expeller (EX101) and has a closed loop fluid circulating system the circulating fluid of which is conveying heat produced in the generator set (GS101), and wherein the closed loop fluid circulating system of the generator set (GS101) is coupled to at least two of the reactor and separator unit (R201), to the buffer tank (TK201), the conditioning chamber / de-gumming process reactor (RlOl) and to the crude oil tank (TK101) for transferring heat and holding the same on an elevated temperature.

1 1. The biodiesel production system as claimed in claim 9 or 10, wherein a pump module (5) comprising at least the majority of the process pumps is provided in the centre of the apparatus.

12. The biodiesel production system as claimed in any one of claims 1 to 1 1 , wherein an apparatus comprising the system is designed to be transportable in a standard 20 ft. container and has a rectangular box shape appearance, where the height and width are approximately the same and 60% of the overall length, and wherein the apparatus is configured to provide two main areas, the first main area for housing process equipment and the second main area having a length of about 1/5 to about 1/3 of the length of the apparatus for standard electrical equipment, the two main areas being divided by a staggered, sealed bulkhead wall (102, 103).

13. A continuous process of producing biodiesel in the biodiesel system of any of claims 1 to 12, which process uses methanol and NaOH as a catalyst to transesterify oil, wherein in the first step the oil is reacted with methanol by mixing with an estimated stoichiometric amount of thereof for transesterifying the oil in the presence of 2 to 10% by weight NaOH catalyst, based on the weight of the methanol, in a first chamber of a reactor, then in a second chamber of the reactor glycerin is separated from the resulting fatty acid methyl ester mixture, which is subsequently reacted for a second time with about 8 to about 15 % of the amount of said mixture containing 2 to 10% by weight NaOH in methanol in a third reaction chamber and then in a fourth chamber of the reactor residual glycerin is separated from the resulting more enriched fatty acid methyl ester mixture to obtain crude biodiesel, wherein the temperature in the process is about 60°C and the pressure is at or slightly above, e.g. up to about 5% or about 10% or about 15%, based on the absolute pressure, above ambient pressure.

14. The continuous process of claim 13, wherein the crude biodiesel is heated to approximately 142°C, then fed into a flash tank, thereafter neutralized in a static mixer with the addition of phosphoric acid, from there flowed into a blending tank to complete the neutralization reaction, then pumped to a resin bed column to remove a major part of the remaining water, then pumped to a final water filter and a polishing filter, and finally collected in a tank.

15. A biodiesel production system, comprising

an oil expeller (EX101) for extracting crude oil from raw feedstock,

a de-gumming process reactor (R101) for removing at least one of gums, metal compounds and other impurities from the crude oil, a reactor and separator unit (R201) for transesterification of the crude oil to methyl esters and for removing glycerin from the methyl esters,

wherein the de-gumming process reactor (R101) and the blending tank (TK205) are formed by a first chamber and a second chamber, respectively, of a twin chamber vessel (CV101) which comprises the first and second chambers in a common housing.

16. The biodiesel production system as claimed in claim 15, wherein a pump module (5) comprising a least a majority of the process pumps is provided in the centre of the apparatus.

17. A biodiesel production system, comprising

an oil expeller (EX101) for extracting crude oil from raw feedstock,

a blending tank (T205) for completing neutralisation reaction,

18. The biodiesel production system as claimed in claim 17, wherein a pump module (5) comprising a least a majority of the process pumps is provided in the centre of the apparatus.