WO2017108957A1

WO2017108957A1 - Hydrogen generating electrolytic cell in alcoholic fermentation medium

Info

Publication number: WO2017108957A1
Application number: PCT/EP2016/082193
Authority: WO
Inventors: Masayuki Kawakami; Antonio Pedro LOURENCO
Original assignee: Mahle Metal Leve S/A; Mahle International Gmbh
Priority date: 2015-12-22
Filing date: 2016-12-21
Publication date: 2017-06-29
Also published as: BR102015032175A8; BR102015032175B1; BR102015032175A2

Abstract

The present invention relates to a hydrogen generating electrolytic cell (10) in a medium of alcoholic fermentation (100) comprising at least a first electrode (20) provided with a first charge and at least a second electrode (30) provided with a second charge opposite to the first charge, the electrodes (20, 30) each possessing at least a surface of contact (21, 31) with the medium of fermentation (100), the surfaces of electrolysis (21, 31) being disposed at a distance one from another and defining a volume of conduction of current (40), the cell (10) permitting hydrogen generation for greater efficiency in the process of fermentation.

Description

Description of patent of invention for ^xHYDROGEN GENERATING ELECTROLYTIC CELL IN ALCOHOLIC FERMENTATION MEDIUM' . [0001] The present invention relates to an electrolytic cell applicable to a process of fermentation, in particular for production of alcohol from sugars, provided with a constructional configuration promoting the efficient generation of hydrogen in the medium in fermentation, leading to a better yield for the process.

Description of the state of the art [0002] Alcohols are a class of chemical compounds characterised by containing at least one hydroxyl group (OH) and are widely utilised in industry. The most well known compound of this class is ethanol or ethyl alcohol. This may be found in alcoholic beverages, in cleaning products, in pharmaceutical products, and is widely utilised as a chemical solvent, and also finds application as fuel for automobiles, this currently being the most notable and intensive use thereof. [0003] The process of production of ethanol is generally undertaken commencing from sugarcane, however it may be undertaken from a variety of grains and sources of sugar, such as maize, cassava, other tubers, sorghum, wheat, barley, and molasses, syrup, cane bagasse, sweet potato, milk whey, etc.

[0004] The manufacture of ethanol is basically divided into 4 phases: crushing, liquefaction, fermentation and distillation. Crushing comprises the passage of the source of sugar through a processor. In this stage a juice is obtained having a high content of water and sugars . [0005] The fermentation part comprises the addition of a type of yeast rendering the transformation of the sugar present in the solution into ethanol. The action of enzymes realises this work. Following this process there is obtained the fermented must already containing part of the total volume thereof converted into ethanol .

[0006] The must then continues on to the final stage, the fractional distillation, giving rise to a solution, the composition whereof will be of ethanol and of water.

[0007] The stage which most directly affects the result of the production of ethanol and, consequently, that most studied, is the fermentation, also referred to as alcoholic fermentation, being the chemical process of transformation of the sugars, principally sucrose, glucose and fructose, into ethanol. In this process microbiological agents participate, being responsible for the conversion of the sugars into ethanol .

[0008] By virtue of being a widely known process in the state of the art, diverse documents may be found describing processes for the aforedescribed purpose. In general, the processes concentrate upon finding a species or a combination of species ideal for the production of ethanol by virtue of the fact that the process utilised involves a significant loss of the raw materials (sugars) , consequently reducing the efficiency of the process.

[0009] In the patent literature diverse documents may be found disclosing different processes for the production of ethanol. The United States patent US 4451566 of Donald B. Spencer describes methods and apparatus for the enzymatic production of ethanol from fermentable sugars. A sequence of enzymes for the catalysation of the conversion of the sugars into ethanol is held in a diversity of reaction zones. The solution of fermentable sugar passes sequentially through these zones and the alcohol is recovered in the final zone. In spite of providing a more efficient reaction than the usual process, this document provides an onerous and complex solution difficult to support. [0010] The international patent application WO 2007/064545 of Brian Burmaster describes a process for improving the yield of the ethanol, decreasing the fermentation time and reducing byproduct formation through controlling the redox potential of the fermenter. However, this process requires very specific and difficult to support monitoring, rendering the process expensive in spite of being more efficient.

[0011] The international patent application WO 2008/024331 of Vladimir Vlad describes a method for magnetic fermentation including subjecting a biological material to a static magnetic field to render the fermentation of the biological material into a fermented product. The fermentation reaction may occur in an alkaline or acid medium and the magnetic field may be positive or negative. Said method makes use of the static magnetic field to provide a more propitious environment for the cellular reproduction of the microorganisms. In spite of increasing the number of microorganisms in the alcoholic fermentation, and in this manner increasing the yield of the reaction, this process requires constant monitoring and total control of the reaction, rendering the process expensive. [0012] Finally, Brazilian patent application BR 11 2015 001644-8 presents a process for the production of alcohol from sugars in the must. The process disclosed utilises at least one pair of electrodes to promote the efficient generation of hydrogen, permitting the polarisation of the sucrose and increasing the efficiency of the process of fermentation. However, the efficiency provided by the electrolytic cell disclosed in BR 11 2015 001644-8 is still lower than would be desirable for a process of fermentation, specifically by virtue of the poor exploitation of the effective area of the electrodes. Objects of the invention

[0013] Having made reference to documents summarily defining that comprised by the prior art, an object of the present invention is to present an electrolytic cell to be applied in the process of fermentation, more particularly in a process of fermentation of sugars for the obtainment of alcohol, possessing a constructional configuration permitting the exploitation of the efficient area of the electrodes and, consequently, an increase in the generation of hydrogen and, therefore, a greater yield in the process of fermentation.

Brief description of the invention [0014] The present invention relates to a hydrogen generating electrolytic cell in a medium of alcoholic fermentation, the cell comprising at least a first electrode provided with a first charge and at least a second electrode provided with a second charge opposite to the first charge, wherein the electrodes each possess at least a surface of contact maintaining partial contact with the medium of fermentation, the surfaces of contact being disposed at a distance from one another and defining a volume of conduction of current . Summary description of the drawings

[0015] The present invention will be described hereinafter in greater detail on the basis of an example of embodiment represented in the drawings. The figures show:

[0016] Figure 1 is a perspective view of a fermentation dome comprising within the interior thereof the electrolytic cell of the present invention in a first preferential configuration;

[0017] Figure 2 is a perspective view of the electrolytic cell of the present invention in a first preferential configuration;

[0018] Figure 3 is a plan view of the electrolytic cell of the present invention in a first preferential configuration ;

[0019] Figure 4 is a side elevation of the electrolytic cell of the present invention in a first preferential configuration; [0020] Figure 5 is a detail of the cross-section D-D of the electrolytic cell of the present invention, as shown in figure 1, in a first preferential configuration . Detailed description of the drawings

[0021] The present invention discloses an electrolytic cell promoting an increase in the efficiency of the production of alcohol by means of the supply of hydrogen to the stage of fermentation of the solutions containing sugars, having the objective of maximum exploitation of the area of contact between the must and the electrodes and the maximum efficiency in the generation of hydrogen in the medium of fermentation. In this respect hydrogen, in the gaseous, ionic and metallic states thereof, is an important element for the maximisation of cellular catabolism and activity in the aerobic and anaerobic processes of yeasts, the present invention providing a manner of obtaining and supplying this element in an efficient manner . [0022] The electrolytic cell 10 of the present invention comprises at least a first electrode 20 provided with a first charge and at least a second electrode 30 provided with a second charge opposite to the first charge, such that a potential difference may be generated between the electrodes.

[0023] Each of the electrodes 20, 30 possesses at least a surface of electrolysis 21, 31, preferentially planar, being enabled to be cylindrical, smooth, corrugated or even of any type, said surface exercising at least partial contact with the medium of fermentation 100 or fermentation liquid.

[0024] The surfaces of electrolysis 21, 31 are disposed at a distance from one another, preferentially opposed, and define a volume of conduction of current which will generate the hydrogen in the medium of fermentation within the limits of that volume, in this manner permitting an increase in the efficiency of the process of fermentation through the release of hydrogen .

[0025] Figures 1 to 5 show the electrolytic cell 10 of the present invention in a first preferential configuration and applied to a fermentation dome 300 constituting a process of obtainment of ethanol from the must of any raw material such as, for example, maize, cassava, other tubers, sorghum, wheat, barley, and molasses, syrup, cane bagasse, sweet potato, milk whey, etc, as aforementioned. The cell 10, according to this first preferential configuration, must work totally submerged in the must wherein the generation of hydrogen will occur. In the dome illustrated, the must is added from the base of the dome, more specifically passing through the centre of the electrolytic cell 10. Alternatively, the filling of the dome may occur in a different manner.

[0026] Figure 2 illustrates the said electrolytic cell 10 in perspective. It may be observed that the said cell 10 is formed by an assembly of electrodes 20, 30 disposed in concentric layers in the form of an annular configuration. Such electrodes possess, in a preferential however not obligatory manner, a rectangular cross-sectional profile, small width and great length, such as elongated plates and are associated in pairs, in a manner being concentric, spaced and in opposition, forming an assembly of concentric layers or rings spaced at a small distance, as illustrated in detail in figure 5.

[0027] The spacing between the electrodes may vary between 1 and 80 mm, wherein in a second configuration the spacing may vary between 3 and 42 mm, wherein in a third preferential configuration the spacing may vary between 9 and 24 mm, wherein in a fourth preferential configuration the spacing may vary between 12 and 36 mm. It must be noted that the spacing between the electrodes may have a fixed value or, alternatively, it may have a variable value.

[0028] Inter alia various factors, one whereof will determine the constructional configuration of the cell and the internal volume of the electrolytic cell 10 in relation to the total working volume of the tank. In this manner, the internal volume of the electrolytic cell 10 varies between 0.1 % and 30 % of the total working volume of the tank. In a second preferential configuration, the internal volume of the electrolytic cell 10 varies between 0.7 % and 10 % of the total working volume of the tank. In other words, the area of the electrolytic cell may vary between 1 m² and 1000 m². This will depend on the volume of the reactor. In this manner, for a reactor of 100 m³ to 120 m³ the area of the electrolytic cell varies between 50 m² and 80 m².

[0029] In a preferential configuration, the closer are located the concentric rings to the centre the length thereof naturally becomes diminished, consequently, in order that the area referring to the surface of contact may be maintained equal between the electrodes, the height of the rings increases the more internal the rings are generating a geometry of the "vortex" type, as may be observed in figure 4. The said circumstance may be attributed to the phenomenon of corrected area. In a second preferential configuration, the electrodes may present constant heights or another type of variation. However, the use of a geometric profile of an electrolytic cell making use of the corrected area has as advantage thereof the fact of increasing the durability of the electrodes and ensuring greater efficiency of the system.

[0030] The association between the pairs of electrodes is realised by nuts and bolts of nylon 160, in conformity with figure 2. The electrodes 20 are preferentially composed of metal alloys resistant to electrochemical corrosion such as, for example, austenitic stainless steels with chromium, nickel and molybdenum, stainless steel 304, 316, 316L, titanium (promoting an effect of reduction of stresses) , and carbon or any material having a coating of carbon (presenting the advantage of ensuring good thermal conductivity) . [0031] The number of pairs of electrodes 20, 30 to be utilised to form the electrolytic cell 10 varies in conformity with the rate of production of ethanol to be adopted, there may be implemented, in terms of example, from eighteen to twenty central electrodes and twelve external electrodes.

[0032] In this preferential configuration each electrode 20, 30 comprises a through orifice 200 formed in a transverse manner in the surface thereof, such that on disposing the electrodes 20, 30 concentrically to one another to form the rings, the orifices 200 are also disposed concentrically configuring an elongated cavity 250 to receive a rod or similar. Considering that each electrode 20, 30 is associated with another for the formation of concentric pairs, and that this association occurs in opposition, the electrolytic cell 10 will possess two substantially opposed cavities 250, in conformity with figure 3. Additionally, the diameter of the orifice 200 formed in each electrode 20, 30 varies intermittently between the sequentially adjacent electrodes 20, 30 for the association of the insulating element 60, as will be seen hereinafter.

[0033] Furthermore, each electrode 20, 30 forming a pair of the ring or layer of the electrolytic cell possesses an orifice 200 of diameter differing from that of its pair. Exemplifying, a first ring or layer formed by a first and a second electrodes 20, 30 will possess a first electrode having a first diameter and a second electrode having a second diameter differing from the first, for association of the insulating element 60, as will be seen hereinafter.

[0034] As is shown in figure 4, the pairs of electrodes 20, 30 are borne upon a support base 50 composed of an assembly of feet 51 and insulators 52. Associated with the insulators 60 there are also separate structures 53 assisting in the definition of a precise spacing between the electrodes, acting as a spacer of the toothed type and a positioner.

[0035] Figure 4 furthermore discloses the presence of a first and a second conductor 70, 71 disposed transversely along the disposition of the electrodes 20. These conductors 70, 71 are connected electrically to a source of energy and are responsible for energising the electrodes 20 such as to configure a potential difference between the same and to permit the generation of hydrogen in the medium of fermentation 100 or must. It should be noted that the current utilised may be direct or alternating, the necessary adjustments being realised as a function thereof. Usually a current of from 0.2 to 40 amperes is utilised or, alternatively, from 0.5 to 36 amperes. Additionally, 1 to 6 volts per cm² or, alternatively, 1.2 to 3.6 V/cm² is applied in a preferential, however not obligatory, configuration.

[0036] Figure 5 reveals the cross-section D-D shown in figure 3. The cross-section illustrated shows the interior of one of the conductors 70, 71. It may be observed that the conductors 70, 71 possess a substantially cylindrical format. Each conductor is disposed within the interior of one of the elongated cavities formed by the orifices 200 of the electrodes 20, in this manner totalling two conductors 70, 71 disposed in opposition, in conformity with figure 3.

[0037] Each conductor 70, 71 is concentrically associated with a multiplicity of substantially tubular insulating elements 60. These insulators 60 are disposed within the interior of the orifices 200 of greatest diameter of the electrodes 20, such that the conductor 70, 71 passes through the middle of the insulator 60, not making contact with the electrodes 20. In this manner, the electrical contact between the electrodes 20 and the conductor 70, 71 is rendered intermittent .

[0038] In this respect, it must be recalled that, as hearinbefore clarified, each electrode 20 forming a pair of the ring or layer of the electrolytic cell possesses an orifice 200 of diameter differing from that of the pair thereof. Consequently, each pair of electrodes 20 or, moreover, each ring or layer formed by a pair of electrodes 20, will be energised by solely one conductor 70, 71. In this manner, considering that the conductors 70, 71 are energised such as to generate a potential difference between both thereof as aforementioned, each layer of the electrolytic cell will present a potential difference in relation to the adjacent layers. [0039] Given the small distance between the layers and the presence of must 150 filling this distance, contact is closed between the adjacent electrodes through the must. In this respect, the cell of the present invention excels in efficiency when compared with the solutions divulged in the state of the art, by virtue of the fact that the entire medium of fermentation present between the rings of adjacent electrodes 20, 30 will generate hydrogen. [0040] By virtue of the fact that the preferential configuration proposed permits the rings to be formed of rectangular plates, the working surface of contact of the present invention greatly surpasses that comprised by, for example, electrolytic cells of the state of the art, and the intermittency provided by the utilisation of the dual electrical contacts 70, 71 utilises an extremely small space, economising an even greater area of contact and, consequently, bringing the advantages of efficiency proposed by the present invention .

[0041] As aforementioned, the present invention furthermore provides for the increased height of each plate of electrodes 20 as the radius of each ring formed by the electrodes 20 diminishes such as to adhere to the geometry of the assembly of insulators 60. In this manner the working area for promoting the generation of hydrogen in the medium of fermentation is rendered even greater.

[0042] Additionally, the impulsion of must within the dome 300 may be of a forced nature (by means of hydraulic pumps) or by convection/buoyancy. In terms of forced pumping, the electrodes 20 may comprise corrugated surfaces with the objective of increasing the turbulence between the said surfaces and preventing deposits arising from the fermentation of the must.

[0043] An example of preferred embodiment having been described, it shall be understood that the scope of the present invention covers other possible variations being limited solely by the content of the claims appended, therein included the possible equivalents .

Claims

1. Hydrogen generating electrolytic cell (10) in a medium of alcoholic fermentation (100), the cell (10) comprising at least a first electrode (20) provided with a first charge and at least a second electrode (30) provided with a second charge opposite to the first charge, the electrolytic cell (10) being characterised in that the electrodes (20, 30) each possess at least one surface of contact (21, 31) maintaining partial contact with the medium of fermentation (100), the surfaces of contact (21, 31) being disposed at a distance from one another and defining a volume of conduction of current (40) .

2. Electrolytic cell (10) according to claim 1, characterised in that it is totally submerged in the medium of fermentation (100) .

3. Electrolytic cell (10) according to claim 2, characterised in that the electrodes (20, 30) possess substantially semicircular or circular geometry.

4. Electrolytic cell (10) according to claim 2, characterised in that the electrodes are each electrically associated with a pair of conductors.

5. Electrolytic cell (10) according to claim 2, characterised in that it is borne by a support base (50) comprising a foot (51) associated with an insulating structure (52).

6. Electrolytic cell (10) according to claim 1, characterised in that it is partially submerged in the medium of fermentation (100) .

7. Electrolytic cell (10) according to claim 1, characterised in that the electrodes (20, 30) possess substantially rectangular geometry.

8. Electrolytic cell (10) according to claim 1, characterised in that, independently of the distance to the centre, all the electrodes present the same area of contact with the medium of fermentation.