BIOPRODUCTS

This invention relates to a hybrid process, the object of which is the production of bioproducts which make up a single reaction system. More specifically, the invention is intended for the integrated production of bioproducts, by means of a biomass fermenting process that uses a reactor specially developed for this purpose. The two main methods for producing bioproducts with the use of microorganisms are: solid state fermentation - SSF - and submerged fermentation - SF. These methods differ from each other due to the ambient conditions they provide for the microorganisms and due to the manner of carrying out the process.

In solid state fermentation, the growth of the microorganisms occurs on solid substrates without the presence of free water (or with only very little free water).

In submerged fermentation, the microorganisms' cells are cultured in a culture liquid medium which supplies the nutrients necessary for their development.

One of the influential parameters that differentiates these methods is the water content of the reaction medium. In SSF, there is an absence or near-absence of free water. However, water is present in the form of a complex or complexes formed with the matrix of a solid raw material. That is, water can be present as a fine absorbed layer on the surface of the particles. In general, the conditions for carrying out this method imitate the conditions found in nature, making it possible for the method to be carried out without prior sterilisation because, due to the low moisture of the solid medium, contamination is not very likely. Consequently, the following can be referred to as the principal advantages of the solid state fermentation method with respect to submerged fermentation:

- for SSF, lower energy demand associated with sterilisation of the medium and recovery of bioproducts,

- the transfer of oxygen to the liquid phase does not limit the ferementation in SSF, it being possible for the fermentation to be carried out in the form of a static culture on a tray,

- with SSF, it is possible to operate with high concentrations of substrate,

- with SSF, output flows are obtained which have greater concentrations of bioproducts, due to the reduced quantity of water present in the reaction medium (compared to SF),

- in general, SSF does not require synthetic nutrients, and

- SSF generates a smaller quantity of liquid residue than SF.

In the specialised literature, various different geometries of reactors can be observed, for use in microbiological methods. These different reactors are operated differently and have different control means. The literature also includes modelling systems to describe the phenomena involved.

The proposals presented in the literature are an attempt to by-pass the limitations of the SSF method and thus make it more attractive. However, the complete dissipation of the metabolic heat generated in SSF has still constituted a challenge to be overcome.

Also found in the literature are reports on various different techniques for improving the integrated production of bioproducts using solid state fermentation.

Patent documents: US 6620614, WO 2008/067800 and WO 2008/102249, cited below, illustrate some of these methods. US 6,620,614 presents a fermenter for obtaining products in large volumes (approximately 1000 litres or more) such as, for example: fungi spores, bacterial biomass, enzymes and antibiotics, among others. The fermenter comprises a cylindrical or oval vessel, the shell of which is impermeable to air and water. Inside this, various plates are superimposed, spaced apart, these being permeable to air and vapour, where microorganisms which are not very competitive can be cultured. The nutrients necessary for culturing each microorganism, according to the objective of the fermentation, are supplied through the top and/or between the plates.

WO 2008/067800 presents a reactor which comprises a horizontal drum which essentially operates in what is commonly termed "plug flow". A stirring system is provided along the whole longitudinal shaft of the drum, forming a type of impeller, to ensure full mixing of the solid dry biomass and to release gas from the reaction chamber. The longitudinal shaft is supported in bearings located internally - close to the walls which form the ends of the vessel - and connected to an external motor.

WO 2008/102249 presents a bioreactor for continuous production of microorganisms and bioproducts by solid state fermentation, which comprises a vertical cylindrical vessel with an inlet for raw material and an outlet for recovery of products and containing: a vertical central tube which runs from the top to the bottom of the vertical shaft of the cylindrical vessel, radial arms connected to the vertical central tube or to the said vertical cylindrical vessel and means for making the said vertical central tube rotate or the vertical cylindrical vessel rotate about its central shaft. Horizontal trays provided with a central hole are fastened on the inside of the vertical cylindrical vessel. The radial arms are located in various different planes and aligned so as to prevent the displacement of the solid matrix through the bioreactor. However, the prior art does not provide reactors for carrying out solid state fermentation associated with submerged fermentation, whereby it would be possible to operate in various different ways, with or without stirring, in a single-batch system or by fed-batch means.

The invention now proposed can meet these requirements by means of equipment specially developed for this purpose.

This invention relates to equipment for obtaining bioproducts, using a hybrid process, the object of which is the production of bioproducts which make up a single reaction system. More specifically, the invention is intended for the integrated production of bioproducts by means of a biomass fermenting process which uses a reactor specially developed for this purpose.

With the use of the above-mentioned reactor, it is possible to attain higher outputs than with the processes carried out in various different reaction vessels and there is lower generation of residue during the process.

According to the invention, there is provided equipment for obtaining bioproducts, wherein the equipment comprises: a reactor comprising multiple compartments for culturing microorganisms; a stirring system, for stirring the contents of the compartments; and wherein at least two of the compartments are separated by a dividing wall provided with a communicating gate valve, which can be moved or removed as required.

Accordingly, the invention provides a reactor, which can be in the form of a drum, which can be internally modified so that different stages of a reaction or fermentation process can be carried out with different internal configurations. The communicating gate valve also allows for different cultures to be kept separate and then combined, which can be useful if different microorganisms are required in an end product but require different initial cultivation conditions. Preferably, the stirring system can be configured to stir with a pendular movement, and optionally so as to sweep from 0% to 75% of the height of the reactor. The stirring system can be configurable to stir either continuously or intermittently. Accordingly the stirring system provides a stirring action as required. However, the pendular motion allows for instruments protruding into the top of the reactor to be avoided by the stirring. Also, the stirring can cause less attrition to the reactor contents than using a rotational stirrer for example.

Stirring with a pendular movement provides operational advantages. For example, there may be sensors measuring temperature in different positions of the reactor (e.g. different points of the solid bed), with wires inside the longitudinal shaft of the stirring system. A rotational movement could create a stress in the wires, and possibly rupture the wires. Stirring with a pendular movement reduces the stress applied to any such wires, for example. Additonally, during product extraction at the end of the solid state fermentation, there is an optional process which involves the use of UV light from a UV lamp in order to kill the microorganisms without denaturing thermally unstable biproducts such as enzymes. A rotational movement could result in the stirring system striking such a lamp, and possibly breaking the lamp. Stirring with a pendular movement reduces the possibility of damaging any such lamp, for example.

The stirring system can comprise an assembly of impeller blades. The impeller blades have different widths. The stirring system can further comprise a longitudinal shaft, and the impeller blades can be fastened to the longitudinal shaft, the shaft passing through the full length of the reactor. In a preferred configuration, the shaft is supported within the reactor by the gate valve. The impeller blades can be spaced apart about the shaft at an angle of 120° to each other. The assembly 100 of impeller blades can be formed by three plates in each compartment, the plates having different shapes and dimensions. An outer blade of the blade assembly can be a plate that is wider than the plates of the other two blades, an intermediate blade of the blade assembly can be a plate which is narrower than the plate of the outer blade, and an inner blade of the plate assembly can be a plate that is narrower than the plates of the other two blades. At least one of the outer and intermediate blades (and preferably both) can have a "U" shaped profile, being hollow in a central part of the plate, and optionally also comprises slots for allowing movement of the blade around thermocouples protruding into the reactor. The inner blade can have a solid profile, and optionally also comprises slots for allowing movement of the blade around thermocouples protruding into the reactor.

Accordingly, the stirring is achieved with a blade assembly of special construction, which is designed to give a thorough stirring performance and thereby assist in mass and heat transfer throughout the reactor contents.

The equipment can further comprise an aeration system formed by a porous plate located adjacent to, or mounted on, the internal surface of the reactor. The aeration system can be located in the lowest part of the reactor. As a result, the aeration is provided at point from which it is evenly dispersed throughout the entire tank contents.

The equipment can further comprise a dispersal system, the dispersal system comprising liquid sprinklers for supplying system nutrients and raw material for culturing microorganisms, and/or sampling nozzles for taking samples for determining the control of the process. The sprinklers can be controllable to operate the reactor in fed-batch mode. This allows for the reactor to keep the moisture content of the system in the desired range for producing the bioproducts desired.

The equipment can be adapted to operate in a hybrid manner, so as to perform both solid state fermentation and submerged fermentation processes. A process of using the equipment can include stages of operation as both solid state fermentation and submerged fermentation. Each compartment can be provided with an individually controllable thermal covering. The thermal covering can be a jacket through which water or steam can be circulated. Optionally, the thermal covering can operate so as to keep the temperature in the range of from 15°C to 80°C. As such, the thermal conditions of each compartment can be individually controlled, so as to provide different culturing conditions for different microbes in different compartments, for example.

According to another aspect of the invention, there is provided a process for obtaining bioproducts, the process comprising a step of using the equipment according to any one of the preceding aspect.

Accoridng to another aspect of the invention, there is provided a process for obtaining bioproducts, characterised in that the process comprises the following stages: supplying, in a reactor comprising multiple compartments (K), microorganisms and nutrients, optionally actuating a stirring system, to mix the contents of the reactor, and adding liquid and opening a gate valve which separates two compartments of the reactor, to allow the transfer of mass between the compartments.

The process can comprise additional stages, according to the particular microorganisms being cultured, including the addition of additional nutrients and/or other raw materials for the fermentation process.

The invention provides equipment for obtaining bioproducts, characterised in that it comprises the following principal components: a cylindrical drum formed by various compartments (K), provided with individual thermal coverings, by means of circulation of water or steam through a drum-covering jacket 20, so as to keep the temperature in the range between 15°C and 80°C and to make possible the simultaneous culturing, in separate conditions, of up to three different microorganisms; a stirring system, which acts by pendular movement, comprising an assembly 100 of impeller blades of special format, fastened to a longitudinal shaft 1 10 which passes through the full length of the drum, which blades are of various different widths and are spaced apart about the shaft at an angle of 120°, an aeration system, formed by a porous plate 30 located close to the internal surface in the lower part of the drum; an upper dispersal system formed by sprinklers (50), with which the moisture content in each compartment (K) can be controlled and means for controlling the operational conditions of the bioproduct production process, for example, temperature.

The equipment for obtaining bioproducts can be characterised in that the cylindrical drum formed by up to three compartments (K), are separated by a dividing wall 10 provided with a communicating gate valve 1 1 , which can be moved or removed when necessary.

The equipment for obtaining bioproducts can be characterised in that the stirring system (M) of the reaction medium uses an assembly 100 of impeller blades, which act by pendular movement so as to sweep from 0% to 75% of the height of the reactor, continuously or intermittently, depending on the requirement of each type of process.

The equipment for obtaining bioproducts can be, characterised in that the said assembly 100 of impeller blades is formed by three plates, of different shapes and dimensions, fastened about a longitudinal shaft 1 10 which passes through the full length of the drum, the outer blade 101 , the plate of which is wider, being positioned at 120° with respect to the horizontal, having a "U"-shaped profile, hollow in its central part and provided with grooves N in its closed portion so that it does not interfere with the thermocouples 90 fitted for control of the temperature in the region close to the centre of the equipment, the intermediate blade 102, the plate of which is narrower, also having a "U"-shaped profile, hollow in its central part and provided with grooves N in its closed portion so that it does not interfere with the thermocouples 90 and the inner blade 103, having the plate much narrower and fully closed, being located at 360° with respect to the horizontal and also being provided with grooves N so that it does not interfere with the thermocouples 90.

The equipment for obtaining bioproducts can be characterised in that the aeration system comprises a porous plate 30 situated in the lower part of the drum, close to the internal surface, which carries out the diffusion of the air with a high surface area, without loss of internal volume of the vessel.

The equipment for obtaining bioproducts can be characterised in that the dispersal system is formed by liquid sprinklers 50 and sampling nozzles 51 , by means of which system nutrients and raw material, necessary for culturing the microorganisms, are supplied and samples are taken for controlling the process.

The equipment for obtaining bioproducts can be characterised in that, with the dispersal system, comprising sprinklers 50 fitted in the upper part of the reactor, the processes can be carried out by fed-batch means, whether for supplying nutrients or only water, contributing to keeping the moisture content of the system in the ideal range for producing the bioproducts desired.

The equipment for obtaining bioproducts can be characterised in that the sprinklers 50 are of a format ensuring that the liquid added reaches the material in the compartment (K) uniformly and in sufficient quantity.

The equipment for obtaining bioproducts can be characterised in that it acts in a hybrid manner, both by means of the solid state fermentation (SSF) process and by means of the submerged fermentation (SF) process.

The invention also provides a hybrid process for obtaining bioproducts, using the equipment described above, characterised in that it comprises the following stages: supplying, in each compartment of the reactor, the raw material, microorganisms and nutrients necessary, controlling the moisture content, temperature of the reaction medium and operational conditions, depending on the microorganism and raw material used; actuating the stirring system, whenever necessary, to mix the layers of materials, promote the mixing of solid and liquid and promote the progressive dissipation of the heat coming from the metabolism of the microorganisms cultured; waiting for the period necessary for obtaining enzymes, of one single type or in a customised manner by the simultaneous culturing of different microorganisms; opening the gate valve which separates the compartments to allow the transfer of mass between at least two compartments; actuating the stirring system to mix the layers of materials and promote the mixing of solid and liquid; waiting for the period necessary for the reaction and formation of products to take place, controlling the temperature of the reaction medium and the operational conditions, depending on the microorganism and raw material used and unloading

The reactor now proposed makes it possible for microorganisms to be cultured in various different growth conditions, in various different raw materials and for formulations to be executed "in situ", for obtaining an enzyme preparation which is optimised and customised for each application desired. The invention is described below, by way of example only with reference to the accompanying drawings, in which:

Fig. 1 shows, in schematic form, a sectional side view of a section of the equipment of the invention;

Fig. 2 shows a cross section of a compartment of the reactor;

Fig. 3 shows a top view of the section of the reactor shown in Fig. 1 ;

Fig. 4 shows a sectional view of the compartment dividing wall and the respective communicating gate valve; and

Fig. 5 shows in detail the forms and dimensions of the impeller blades used in the equipment of the invention. With the equipment of the invention, it is possible to obtain bioproducts both through both the solid state fermentation (SSF) process and through the submerged fermentation (SF) process. This is, therefore, a hybrid process which can be carried out simultaneously in one single piece of equipment. In general, the equipment can comprise the principal components discussed below.

The equipment can have a drum, which is preferably cylindrical for ease of mixing. The drum can have multiple compartments K, prefereably up to three compartments K. Each compartment K can be provided with individual thermal coverings (i.e. allowing control of each compartment according to different desired thermal conditions). As such multiple (preferably up to three) different microorganisms can be cultured at the same time, in separate conditions (i.e. each different microorganism can be cultured in a different compartment K).

The equipment can have a stirring system, which preferably acts by pendular movement. The stirring system can comprise an assembly 100 of impeller blades. Preferably, as discussed in more detail below, with reference to Fig. 5, the blades have a special format. The blades can be fastened to a longitudinal shaft 1 10, which can pass through the full length of the drum. The blades can be of various different widths and can be spaced apart about the shaft at an angle of 120° to each other.

The equipment can have an aeration system, preferably formed by a porous plate 30. The porous plate 30 can be located close to the internal surface in the lower part of the drum.

The equipment can have an upper dispersal system, preferably formed by sprinklers 50. The sprinklers 50 can be operated to adjust and control the moisture content in each compartment K.

The equipment can have a means for control of the operational conditions of the process for producing bioproducts. Figs 1 , 2 and 3 show a section of the equipment of the invention comprising two compartments K1 and K2: Fig. 1 is a sectional side view , Fig 2 is a cross section of any compartment K and Fig. 3 is a top view of this section of the equipment.

As can be seen with the aid of Fig. 1 , the compartments K1 and K2 that make up the reactor R are separated by a dividing wall 10. The dividing wall is provided with a communicating gate valve 1 1 , which can be moved or removed when necessary. When in place and fully closed, the gate valve 1 1 prevents any material transfer between the two compartments K1 and K2. However, transfer between the compartments K1 and K2 becomes possible when the gate valve 1 1 is opened or removed.

The walls of the drum which forms the reactor R body are covered externally with a reactor jacket 20. The jacket can act as a means of cooling or heating. Areas of the jacket 20 around th different compartments K can be controlled independently. This can be achieved either by providing multiple individual jackets 20 (i.e. at least one for each compartment K) or by providing a single jacket 20 with individually controllable areas (again, at least one for each compartment K)

Internally and close to the lower wall of the drum, there is the reactor

R aeration system. This is formed by a porous plate 30 which preferably runs the length of the drum. The plate 30 communicates with the outside environment by means of air or oxygen injection nozzles 40.

One or more of the following can be provided in the upper part of the drum, as shown in Fig. 1 : the dispersal system, optionally formed by liquid sprinklers 50; sampling nozzles 51 , through which system nutrients and raw material - necessary for culturing the microorganisms - can be supplied and through which samples can be taken (e.g. for use in controlling the process); passages 60 for outlet of gases; and means of access 70 for inserting (for example) instruments for controlling the operational conditions of the fermentation process.

One or more of the following can be provided in the lower part of the drum, as shown in Fig. 1 : drains 80 for drawing off products and solids in suspension; and means of access 90 for fitting (for example) thermocouples for temperature control.

The stirring system of the reaction medium is preferably formed by an assembly 100 of impeller blades. The blades can be fastened to a longitudinal shaft 1 10 that passes through the full length of the drum. Preferably, the shaft 1 10 is supported both internally in the communicating gate valve 1 1 , which is provided in the dividing wall 10 between the compartments K, and in the ends of the drum. The shaft 1 10 is connected to suitable actuation means (not shown in the figures).

The above-mentioned assembly 100 of impeller blades is preferably formed by three blades in a given compartment K. The three blades are further preferably of the form discussed below in connection with Fig. 5, having various different widths and being spaced apart about the shaft at an angle of 120° to each other.

Fig. 2 shows in greater detail the drum-covering reactor jacket 20 and its inlet point E and outlet point S for cooling or heating liquid to pass through. In other embodiments, the heating may be achieved electrically (e.g. by resistive heating in the jacket 20), rather than by passing a heating fluid through the jacket 20. Fig. 2 also shows the porous plate 30 as being situated in the lower part of the drum, close to the internal surface, and the aeration system provided with air/oxygen injection nozzles 40. By providing the porous plate 30 and air/oxygen injection nozzles 40 in the bottom of th drum, the air/oxygen introduced can bubble right the way through any liquid medium in the drum, achieving the best possible mass transfer to the culture medium. Fig. 2 also shows the dispersal system, comprising special sprinklers 50. The sprinklers 50 are designed and positioned to distribute liquid evenly across the drum.

Fig. 3 shows a top view of the section of the reactor R shown in Fig. 1. From Fig. 3 is is possible to visualise the way in which the various different systems and their components are distributed along the drum which forms the reactor R.

The dividing wall 10, which separates the compartments K, is provided with a movable gate valve 1 1 , as mentioned above and shown in detail in Fig. 4. This option of dividing the reactor R into separate compartments, or combining previously separate compartments, represents one of the advantages of the equipment. This is because it makes it possible, in one single piece of equipment, to culture various different microorganisms simultaneously, in separate operational conditions, and subsequently combine them into a single mixed culture system. As such, different bioproducts can be simultaneously produced by means of a hybrid process using the equipment, the different bioproducts being intended for making up a single reaction system.

The equipment of the invention, in its preferred embodiment, provides for the fitting of three compartments, making it possible to culture up to three different microorganisms at the same time.

The stirring system of the reaction medium preferably uses an assembly 100 of impeller blades. As mentioned above, the blades can act by pendular movement (e.g. swinging back and forth, as opposed to continuously rotating around the shaft 1 10) so as to sweep from 0% to 75% of the height of the reactor, in a continuous or intermittent manner, according to the requirement of each type of process. The impeller blades improve mixing of any layers of solid and liquid materials located in the regions closest to the centre of the equipment with the layers of more distant materials. The impeller blades preferred for the invention have been developed with a specific shape to promote the mixing of the layers of solids and provide better heat transfer between the layers. This also assists the outlet of the hot gases coming from the metabolism of the microorganisms.

Fig. 5 shows in detail the shapes and dimensions of the impeller blades preferred for use in the equipment.

In practice, the assembly 100 of impeller blades comprises three plates, of different shapes and dimensions. The plates can be fastened about a longitudinal shaft 1 10 which preferably passes through the full length of the drum. The plates are preferably spaced apart from one another at an angle of 120°.

The outer blade 101 , the plate of which is the widest (i.e. which extends the furthest radial distance from the shaft), is positioned at 120° to the horizontal (in a frame of reference defined for the sake of this part of the description - in use the position of the blade will change). It has a substantially "U"-shaped profile. That is, the blade plate has a empty portion or hollow in its central part, such that the remaining solid (in contrast to the empty or hollow portion) plate forms a "U" with respect to the shaft 1 10. The blade is also provided with one or more grooves N in its solid portion. The grooves N are positioned such that the blade does not interfere with the thermocouples 90 fitted for control of the temperature in the region close to the centre of the equipment. That is, as the blade moves towards and past the thermocouples 90, the thermocouples are aligned with and pass through the grooves N.

The intermediate blade 102, the plate of which is narrower than the outer blade 101 , also has a substantially "U"-shaped profile, as described for the outer blade 101 . It is positioned at 120° to the outer blade 101 - i.e. the intermediate blade 102 is positioned at 240° with respect to the horizontal in the frame of reference defined above. It is also provided with grooves N so that it does not interfere with the thermocouples 90. Finally, the inner blade 103 is narrower than the intermediate blade 102 and is fully closed - that is, there is no empty or hollow portion, the blade is solid throughout. The inner blade 103 is located at 360° with respect to the horizontal in the frame of reference defined above, and is also provided with grooves N so that it does not interfere with the thermocouples 90.

By operating an assembly of the impeller blades described above with a pendular movement, progressive dissipation of the heat coming from the metabolism of the microorganisms cultured in the bioreactor, layer to layer of solid, is made possible. As a result, the growth of the microorganisms themselves is not impaired by excess heat and the bioproducts produced are not denatured due to an increase in temperature.

In a preferred embodiment, the thermal conditioning of the equipment is carried out by means of circulation of water or steam through the drum-covering reactor jacket 20, so as to keep the temperature in the range between 15°C and 80°C.

The dispersal of air/oxygen (0 ₂ ) necessary for metabolism takes place by means of the aeration system comprising the porous plate 30 that is shown situated in the lower part of the drum, close to the internal surface, in Fig. 1. This makes it possible for the diffusion of the air/oxygen to occur over a high surface area (improving the mass transfer characteristics of the vessel), without loss of internal volume of the vessel.

In addition, with the dispersal system, preferably comprising sprinklers 50 fitted in the upper part of the reactor, the processes can be carried out in fed-batch form. This is the case whether the sprinklers 50 are used for for supplying nutrients or only water. The dispersal system thus contributes to keeping the moisture content of the system in the ideal or desired range for producing the bioproducts desired. The sprinklers 50 are distributed, and of a format, designed to ensure that the liquid added reaches the material in the compartment uniformly and in sufficient quantity.

Other advantages of the equipment of the invention will become evident as its operation is described. Advantages of the integrated process are the reduction of operational costs and the maximisation of utilisation of the resources available. So, one possibility for operation of the equipment of the invention is to carry out the process of obtaining bioproducts in an integrated manner, in accordance with the following four principal stages:

1 - production of enzymes in a solid culture medium, in a customised manner,

2 - reaction of the enzymes on the solid substrates in a submerged medium,

3 - production of intermediate products, and

4 - production of end products of interest.

In this way, the equipment finds application in various different areas of technology, especially to the pharmaceutical, petroleum, gas and energy industries, e.g. for production of biopolymers and biofuels.

A preferred manner of carrying out the process will be described below, in accordance with its principal process routes. The skilled reader will understand that the specific conditions used in the process will vary, depending on the microorganism used and products of interest.

When setting the equipment up, solid residues known in the art and generally used as fermentation raw materials (such as agro-industrial residues and lignocellulosic materials, amongst others) are introduced into the equipment. This can be achieved via sampling nozzles 51 , located on the upper part of the reactor, for example. The microorganisms can also be added together with the solids. Ultraviolet (UV) lamps can also be fitted in these nozzles to prevent contamination.

Any water content can be supplied via the dispersal system, for example by means of the special sprinklers 50, designed to maximise the sweeping area (i.e. the dispersal of the liquids by the sprinklers) of the liquids injected. In some situations, the dispersal system can also be used for supplying a solution with nutrients for the microorganisms used in the process.

The stirring system formed by the assembly 100 of impeller blades can be actuated to ensure the homogeneity of the mixture of the liquid and solid phases. Depending on the type of reaction which it is wished to promote, the stirring system can be actuated intermittently or continuously.

The oxygen for the microorganisms can be supplied by means of the injection nozzle 40 of the aeration system, for example via the porous plate 30. The plate 30 maximises the dispersal of the air and/or oxygen through the bed where the raw material and microorganisms are.

This first stage mentioned above for production of enzymes in the solid culture medium, can be of a duration that varies between 12 and 240 hours and the products obtained are enzymes for application in industrial processes.

The second stage of the process starts with the addition of liquid, via the dispersal system for example, so as to convert the solid state fermentation (SSF) process to the submerged fermentation (SF) process. The gate valve 1 1 which interconnects the compartments K of the reactor is opened during this second stage, promoting the transfer of mass between the compartments. In this way, bioproducts which have been synthesised in one compartment can react either with the non-reacted raw material of the adjacent compartment or of the very compartment in which it has been generated.

The impeller blade stirring system can be actuated, if necessary, to mix the layers which are closest to and those which are furthest from the central shaft, for keeping the solids in suspension in the liquid.

The introduction of these added materials into the process is expected to initiate (biological) reactions in the reactor R. At this stage, the temperature is kept in the range between 30°C and 80°C, for a period which can vary, for example, from 4 to 96 hours depending upon the process. In general, this stage takes place without the addition of oxygen, but oxygen can be added if required for a particular process.

The object of the third stage mentioned above is to obtain intermediate products. However, this is not an obligatory stage, if for example, such intermediate products are not required. If the third stage is implemented, a new quantity of raw material can be added through the sampling nozzles 51. The raw material can then be subjected to the reaction with the enzymes generated in the initial stage of the process. Preferably, the stirring of the system is continued, so as to ensure the effective mixing of the materials. In general, this stage takes place without aeration (although aeration can be provided if required for the particular process), for a period which can vary, for example from 4 to 96 hours, depending upon the particular process.

The fourth principal stage comprises the addition of different microorganisms from the one used originally. A new quantity of raw material can also be added. The reactor can continue to use stirring so that the products generated at the earlier stages can be consumed by the new microorganisms. As such, new products of interest can be generated. At this stage, there may be a need for aeration of the reaction medium, which can be supplied as needed. It can be desirable to keep the temperature in the range from 15°C to 80°C for this stage, but that will depend upon the specifics of the process. In general, this stage can last for approximately 8 to 240 hours, but again that will depend on the particular process.

The products generated can be drawn from the reactor through the drains 80. Preferably, the drains 80located in the lower part of the reactor, to assit with emptying the reactor as completely as possible. Therefore, the process of obtaining bioproducts by means of the hybrid process described herein, can comprise, in summary form, the following stages:

- supplying, in each compartment of the reactor, the raw material, microorganisms and nutrients necessary; controlling the moisture content, temperature of the reaction medium and operational conditions, depending on the microorganism and raw material used,

- actuating the stirring system, whenever necessary, to mix the layers of materials, to promote the mixing of solid and liquid and to promote the progressive dissipation of the heat coming from the metabolism of the microorganisms cultured,

- waiting for the period necessary for obtaining enzymes, of one single type or in a customised manner by the simultaneous culturing of different microorganisms,

- opening the gate valve which separates the compartments to allow the transfer of mass between at least two compartments,

- actuating the stirring system to mix the layers of materials and promote the mixing of solid and liquid,

- waiting for the period necessary for the reaction and formation of products to take place; controlling the temperature of the reaction medium and the operational conditions, depending on the microorganism and raw material used and

- unloading the reactor and recovering the products of interest.

The invention has been described on the basis of its preferred embodiment. However, it becomes evident that persons skilled in the art will be able to introduce changes and alterations without abandoning the inventive concept disclosed here, which concept is limited by the following claims.