Abstract
The present invention relates to a method for cultivating a microorganism capable of utilizing an organic feedstock, comprising the steps of: (i) cultivating the microorganism in one or more bioreactors (1); (ii) capturing CO.sub.2 from the one or more bioreactors (1) and reducing the CO.sub.2 to an organic feedstock in a reduction unit (3); and (iii) feeding at least a part of the organic feedstock from the reduction unit (3) into one or more bioreactors (1).
Claims
1. Method for cultivating a microorganism capable of utilizing an organic feedstock, comprising: cultivating the microorganism in one or more bioreactors; (ii) capturing CO.sub.2 from the one or more bioreactors and reducing the CO.sub.2 to an organic feedstock in a reduction unit; and (iii) feeding at least a part of the organic feedstock from the reduction unit into one or more bioreactors.
2. The method according to claim 1, wherein the organic feedstock is chosen from the group consisting of formic acid, methanol, ethylene, ethanol, 1-propanol, methane, acetic acid and carbon monoxide.
3. The method according to claim 1, wherein the organic feedstock is formic acid.
4. The method according to claim 1, wherein the microorganism is chosen from the group consisting of yeast, filamentous fungi, bacteria and heterotrophic algae.
5. The method according to claim 1, further comprising: (iv) electrolyzing water into H.sub.2 and O.sub.2 in an electrolysis unit, and feeding at least a part of the H.sub.2 into the reduction unit for reducing the CO.sub.2 to the organic feedstock.
6. The method according to claim 5, further comprising: (v) feeding at least a part of the O.sub.2 into the one or more bioreactors.
7. The method according to claim 5, further comprising: (v) feeding at least a part of the H.sub.2 into the one or more bioreactors.
8. The method according to claim 1, wherein the microorganism capable of utilizing an organic feedstock comprises at least one polynucleotide coding for a compound of interest or at least one polynucleotide coding for a compound involved in the production of a compound of interest by the cell.
9. The method according to claim 1, comprising monitoring fermentation process comprising: (vi) selecting at least one process parameter of the fermentation, for which current measured values are determined during the course of the fermentation process; (vii) comparing a respective current measured value of the at least one selected process parameter with a corresponding estimated value of a model parameter estimated by a process model for said at least one process parameter; (viii) comparing a variance between the respective current measured value and the corresponding estimated value for the at least one selected process parameter with a predetermined threshold value; and (ix) changing at least one defined model parameter employed in the process model when the predetermined threshold value is exceeded by the variance: wherein (vii) to (ix) with a respective changed model parameter are executed until the variance is placed below a predetermined threshold value; and optionally wherein in case that, after a predetermined number of repetitions of (vii) to (ix) the threshold value is met by the variance, the method is discontinued and a warning is generated as output.
10. A System for cultivating a microorganism capable of utilizing an organic feedstock, said system comprising one or more bioreactors for cultivating said microorganism, a CO.sub.2 capturing unit for capturing CO.sub.2 from the one or more bioreactors, a CO.sub.2 reduction unit for reducing the CO.sub.2 to organic feedstock, and one more conduits to introduce the organic feedstock into one more bioreactors.
11. The system according to claim 10, further comprising an electrolysis unit for electrolysis of water and a conduit to introduce H.sub.2 from the electrolysis unit to the CO.sub.2 reduction unit.
12. The system according to claim 10, further comprising one or more conduits for introducing H.sub.2 and/or O.sub.2 into the one or more bioreactors.
13. The system according to claim 10, further comprising one or more inlets introducing substrate into the one or more bioreactors and one or more outlets for product formed in the one or more bioreactors.
14. The system according to claim 10, further comprising a computer implemented system for a fermentation simulation tool for simulating a fermentation method, said computer implemented system comprising at least one processor, a user interface, a control system interface configured to adjust one or more process parameters of the fermentation method, a memory comprising computer readable medium storing instructions for simulating the fermentation method, wherein the instructions for simulating the fermentation method configure the processor to: (vi) selecting at least one process parameter of the fermentation method, for which current measured values are determined during the course of the fermentation method; (vii) comparing a respective current measured value of the at least one selected process parameter of the fermentation method with a corresponding estimated value of a model parameter estimated by a process model for this at least one process parameter; (viii) comparing a variance between the respective current measured value and the corresponding estimated value for the at least one selected process parameter with a predetermined threshold value; and (ix) changing at least one defined model parameter employed in the process model when the predetermined threshold value is exceeded by the variance: wherein (vii) to (ix) with a respective changed model parameter are executed until the variance is placed below a predetermined threshold value; and optionally wherein in cases that, after a predetermined number of repetitions of steps (vii) to (ix) the threshold value is met by the variance, the method is discontinued and a warning is generated as output on the user interface.
Description
DESCRIPTION OF THE FIGURES
[0079] In the embodiment of FIG. 1, the substrate sugar is introduced via conduits 13 into bioreactor 1. The bioreactor 1 provides the conditions allowing fermentation of microorganisms capable of utilizing organic feedstock. The produced product, like the microorganism or a compound of interests produced by the microorganisms, leaves the bioreactors 1 via conduits 14. CO.sub.2 formed in the bioreactors 1 is introduced into a CO.sub.2 capture unit 2 via conduits 15. In reduction unit 3 the CO.sub.2 is reduced towards organic feedstock, utilizing H.sub.2. The organic feedstock is introduced into bioreactors 1 via conduits 10, enabling fermentation of the microorganisms that are capable to utilize the organic feedstock. Preferably the amount of organic feedstock introduced into bioreactors is less than the amount of substrate sugar. The advantage is that CO.sub.2 is not released into the environment, and the amount of sugar needed for the fermentation process can be reduced. The H.sub.2 needed for reduction of CO.sub.2 into organic feedstock can be introduced into reduction 3 and can be sourced from a supplier. Preferably, the electrolysis unit 4 electrolyzes water into H.sub.2 and O.sub.2. The H.sub.2 can be introduced into reduction unit 3 via conduit 11. The O.sub.2 can be introduced into bioreactor 1. Alternatively, air can be introduced into bioreactor 1 for aerobic processes.
[0080] In the embodiment of FIG. 2, in addition to the embodiment of FIG. 1, a second bioreactor 1′ is present. The electrolysis unit 4 electrolyzes water into H.sub.2 and O.sub.2. The H.sub.2 can be introduced into reduction unit 3 via conduit 11. Advantageously, H.sub.2 can be introduced in a bioreactor 1′ for fermentation of microorganisms capable of utilizing H.sub.2. This is advantageous in that H.sub.2 cofeeding reduces the amount of sugar needed, and can reduce the amount of CO.sub.2 formed by the microorganisms in bioreactor 1′.
[0081] FIG. 3 shows a calculation of required substrate and O.sub.2, the produced ethanol and yeast, and the emitted CO.sub.2, in a conventional system.
[0082] In the embodiment of FIG. 4, aerobic bioreactor 1 produces yeast via outlet 14, using sugar via inlet 13 and O.sub.2 via inlet 12. The O.sub.2 is produced by electrolysis unit 4. The electrolysis unit 4 produces H.sub.2 that is introduced in reduction unit 3 via conduit 11. CO.sub.2 from the aerobic bioreactor 1 is captured in unit 2, via conduit 15. The CO.sub.2 is reduced to formic acid in reduction unit 3 and introduced into yeast bioreactor 1 via conduit 10.
[0083] In operation, the embodiment of FIG. 4 allows production of the same amount of yeast as in FIG. 3. However, no CO.sub.2 is released into the environment, and the amount of sugar and O.sub.2 needed for yeast fermentation is significantly reduced.
[0084] In the embodiment of FIG. 5, an aerobic fermentation for production of yeast in bioreactor 1 is combined with anaerobic ethanol fermentation for production of ethanol in bioreactor 1′. O.sub.2 produced by electrolysis unit 4 is introduced into aerobic yeast bioreactor 1 via conduit 12. H.sub.2 produced by electrolysis unit 4 is introduced into anaerobic ethanol bioreactor 1′ via conduit 12′ and into reduction unit 3 via conduit 11. CO.sub.2 is only captured from aerobic yeast bioreactor 1 via conduit 15. Formic acid is introduced in aerobic yeast bioreactor 1 only via conduit 10, and any surplus formic acid is collected for external use.
[0085] In operation, the embodiment of FIG. 5 allows the production of ethanol without production of CO.sub.2. Further the amount of sugar needed for production of ethanol is reduced due to feeding the H.sub.2. The aerobic yeast fermentation produces the same amount of yeast using a reduced amount of sugar. No CO.sub.2 is released into the environment. The O.sub.2 needed for fermentation is totally derived from the electrolysis unit. Hence, FIG. 5 shows a system allowing a CO.sub.2 neutral fermentation process.
[0086] In the embodiment of FIG. 6, an aerobic yeast production in bioreactor 1 is combined with anaerobic ethanol production in bioreactor 1′. O.sub.2 produced by electrolysis unit 4 is introduced into aerobic yeast bioreactor 1 via conduit 12. H.sub.2 produced by electrolysis unit 4 is introduced into reduction unit 3 via conduit 11. CO.sub.2 is only captured from anaerobic ethanol bioreactor 1′ via conduit 15. Formic acid is introduced in aerobic yeast bioreactor 1 only via conduit 10.
[0087] In operation, the embodiment of FIG. 6 only produces the amount of formic acid required for the aerobic yeast fermentation in bioreactor 1. Any surplus CO.sub.2 from both bioreactors 1 that is not needed for production of formic acid is released. This embodiment allows a reduction of sugar needed for fermentation of yeast, while it minimizes the energy needed for electrolysis of water in electrolysis unit 4.
[0088] In the embodiment of FIG. 7, aerobic bioreactor 1 produces yeast via outlet 14, using sugar via inlet 13 and O.sub.2 via inlet 12. Anaerobic bioreactor 1′ produces ethanol via outlet 14′ using sugar via inlet 13′. CO.sub.2 from both the aerobic yeast bioreactor 1 and anaerobic ethanol fermentation bioreactor 1′ is captured in unit 2, via conduits 15. The CO.sub.2 is reduced to formic acid in reduction unit 3 and introduced into both the aerobic yeast bioreactor 1 and anaerobic ethanol fermentation bioreactor 1′ using conduits 10. Any surplus formic acid is collected via an outlet on conduit 10. Electrolysis unit 4 electrolyzes water into H.sub.2 and O.sub.2. The H.sub.2 is introduced in reduction unit 3 via conduit 11. The O.sub.2 is introduced in the aerobic yeast fermentation bioreactor 1. Any surplus O.sub.2 leaves the system via conduit 16.
[0089] In operation, the embodiment of FIG. 7 reaches ethanol and yeast production using minimal amounts of sugar. All CO.sub.2 is captured and reduced to formic acid. The microorganisms grown in the bioreactors are capable in utilizing formic acid. In the embodiment of FIG. 8, CO.sub.2 from both the aerobic yeast bioreactor 1 and anaerobic bioreactor 1′ is captured in unit 2, via conduits 15. The CO.sub.2 is reduced to formic acid in reduction unit 3 and introduced into both the aerobic yeast bioreactor 1 and anaerobic bioreactor 1′ using conduits 10. Electrolysis unit 4 electrolyzes water into H.sub.2 and O.sub.2. The H.sub.2 is introduced in reduction unit 3 via conduit 11. The O.sub.2 is introduced in the aerobic yeast fermentation bioreactor 1. Any surplus O.sub.2 leaves the system via conduit 16.
[0090] In operation, the embodiment of FIG. 8 reaches ethanol and yeast production using minimal amounts of sugar. The amount of CO.sub.2 that is captured and reduced to formic acid is adapted to the amount needed for the production of formic acid. Any CO.sub.2 surplus is emitted. The microorganisms grown in the bioreactors only need to be capable in utilizing formic acid. In this embodiment, the electricity is reduced to what is needed for the minimal electrolysis of water for formation of formic acid.
[0091] FIG. 9 shows a calculation of required substrate and O.sub.2, the produced penicillin and yeast, and the emitted CO.sub.2, in a conventional system.
[0092] FIG. 10 shows an embodiment of the invention wherein CO.sub.2 from both the aerobic yeast bioreactor 1 and aerobic penicillin bioreactor 1′ is captured in unit 2 via conduits 15. The CO.sub.2 is reduced to formic acid in reduction unit 3 and introduced into both the aerobic yeast bioreactor 1 and aerobic penicillin bioreactor 1′ using conduits 10. Electrolysis unit 4 electrolyzes water into H.sub.2 and O.sub.2. The H.sub.2 is introduced in reduction unit 3 via conduit 11. The O.sub.2 is introduced in the aerobic yeast fermentation bioreactor 1 and the aerobic penicillin bioreactor 1′. The yeast in bioreactor 1 is capable of utilizing formic acid. The penicillium in bioreactor 1′ is capable of utilizing formic acid.
[0093] In operation, the embodiment of FIG. 10 produces the same amount of penicillium and yeast as in comparative FIG. 9, while the amount of sugar needed to produce the same yield is reduced from 63.3 kt to 48.6 kt, and the amount of externally supplied O.sub.2 is reduced from 31.8 kt to 16.1 kt.
