WO2023186702A1

WO2023186702A1 - Process and apparatus for recovering hydrogen from a hydrocarbon reservoir

Info

Publication number: WO2023186702A1
Application number: PCT/EP2023/057510
Authority: WO
Inventors: Johannes Fabian Bauer; Moh'd Amro
Original assignee: Technische Universität Bergakademie Freiberg
Priority date: 2022-04-01
Filing date: 2023-03-23
Publication date: 2023-10-05
Also published as: DE102022203277B3

Abstract

A process and an apparatus for recovering hydrogen from a hydrocarbon reservoir are provided. It is a feature of the process and the apparatus that a liquid comprising or consisting of water and at least one surfactant is injected into at least one first well of the hydrocarbon reservoir, the wells of the hydrocarbon reservoir are closed, there is an incubation period of at least two weeks, and, after opening of the at least one first well and/or of at least one second well of the hydrocarbon reservoir, a hydrogen-containing fluid is produced and hydrogen is recovered from the hydrogen-containing fluid. The process and the apparatus permit economic and efficient recovery of hydrogen on an industrial scale from a hydrocarbon reservoir, especially from an (already) depleted fossil hydrocarbon deposit.

Description

Process and system for obtaining hydrogen from a hydrocarbon reservoir

A process and a system for obtaining hydrogen from a hydrocarbon reservoir are provided. The method and the system are characterized in that a liquid which contains or consists of water and at least one surfactant is injected into at least a first borehole of the hydrocarbon reservoir, the boreholes of the hydrocarbon reservoir are closed, and incubated for a period of at least two weeks and after opening the at least one first borehole and/or at least one second borehole of the hydrocarbon reservoir, a hydrogen-containing fluid is conveyed and hydrogen is obtained from the hydrogen-containing fluid. The process and the system allow hydrogen to be extracted economically and efficiently on an industrial scale from a hydrocarbon reservoir, in particular from an (already) exhausted fossil hydrocarbon deposit. Liu, J.-F. et al. (The diversity of hydrogen-producing microorganisms in a high temperature oil reservoir and its potential role in promoting the in situ process, Applied Environmental Biotechnology, Vol. 2, pp. 25-34, 2016) examined hydrogen-producing microorganisms in the production water of an oil field as well as enrichment cultures Genes coding for [FeFe] hydrogenase using a clone library. The results showed that the [FeFe] hydrogenase genes in produced water are diverse and belong to Bacteroidetes, Firmicutes, Spirochaetes and uncultivated. The results suggest that hydrogen-producing microorganisms in oil reservoirs can play a positive role in promoting the in situ bioprocess through hydrogen production once common nutrients are available.

Veshareh, M.J. et al. (The light in the dark: ln-situ biorefinement of crude oil to hydrogen using typical oil reservoir, International Journal of Hydrogen Energy, Vol. 47, pp. 5101-5110, 2022) reveal that microorganisms such as microorganisms of the species Pseudothermotoga, isolated from hydrocarbon deposits, are capable of converting hydrocarbons into H2. The addition of glucose and the nonionic surfactant Tween 80 was found to increase ^ production from hydrocarbons 12-fold. However, adding glucose to increase the efficiency of the hydrogen yield has the disadvantage that the process becomes very expensive and therefore uneconomical, especially when producing hydrogen in very large quantities (i.e. on an industrial scale), since glucose is a relatively expensive energy source. Furthermore, this publication does not specify how hydrogen can be efficiently extracted from a fossil (exhausted) hydrocarbon deposit (e.g. a fossil mature oil deposit).

The processes described in the prior art have the disadvantage that they are not very economical, ie economical production of industrial quantities of hydrogen from a hydrocarbon source is not possible. Furthermore, the methods known in the prior art do not specify how to extract a fossil (extracted) hydrocarbon deposit (e.g. a mature fossil oil deposit) in an economical and efficient manner and industrially relevant quantities of hydrogen can be obtained.

Based on this, the object of the present invention was to provide a method and a system which do not have the disadvantages of the prior art. In particular, a process and a system should be provided that allow a more economical and efficient extraction of hydrogen on an industrial scale from a hydrocarbon reservoir, in particular from an (already) exhausted fossil hydrocarbon deposit.

The task is solved with the method with the features of claim 1 and the system with the features of claim 8. The dependent claims show advantageous developments.

According to the invention, a method for obtaining hydrogen from a hydrocarbon reservoir is provided, comprising the steps or consisting of the steps: a) using a hydrocarbon reservoir which has an oil-containing zone with a mobile water phase, the hydrocarbon reservoir having at least a first borehole which is located from a surface of the hydrocarbon reservoir extends over an upper region of the oil-containing zone, into an upper region of the oil-containing zone, or into a lower region of the oil-containing zone; b) injecting a liquid containing or consisting of water and at least one surfactant into the at least one first borehole of the hydrocarbon reservoir, the liquid being injected at a liquid temperature in the range of 40 ° C to <120 ° C; c) closing at least the at least one first borehole of the hydrocarbon reservoir; d) incubate for a period of at least two weeks; e) conveying hydrogen-containing fluid from the hydrocarbon reservoir through the at least one first borehole after opening the at least one first borehole, if the at least one first borehole extends from the surface of the hydrocarbon reservoir to over the upper region of the oil-containing zone of the hydrocarbon reservoir, and/or producing hydrogen-containing fluid from the hydrocarbon reservoir through at least one second borehole after opening the at least one second borehole, wherein the at least one second borehole of the hydrocarbon reservoir extends from a surface of the hydrocarbon reservoir to over an upper region of the oil-containing zone or extends into a lower region of the oil-containing zone; and f) recovering hydrogen from the hydrogen-containing fluid.

The process has the advantage that it allows economical and efficient extraction of hydrogen on an industrial scale from a hydrocarbon reservoir, in particular from an (already) exhausted fossil hydrocarbon deposit.

The economical and efficient production of hydrogen results, for example, from the fact that the injected liquid contains at least one surfactant. The oil dispersed in water enables microorganisms that reside in the water phase and are capable of converting hydrocarbons into hydrogen to effectively absorb the oil or hydrocarbons and thus produce hydrogen in an efficient manner.

Furthermore, an economical and efficient production of hydrogen can result from discharging the liquid into an upper region of the oil-containing zone (ie into a gas cap region of the hydrocarbon reservoir, which is formed by an already existing (primary) gas cap and/or by a gas cap created during the process ( secondary) gas cap is or will be formed) or to inject into an upper region of the oil-containing zone. The at least one surfactant in the water causes oil in the oil-containing zone to be better dispersed in the injected water. The formation of the dispersion is efficient in the case of these injection sites because the injected liquid must pass by gravity through a long section of the oil-bearing zone before reaching the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir. Since no additional energy input is necessary for efficient mixing (e.g. by adding mixing energy), the process is also very economical. Apart from that, the liquid can be injected into a lower region of the oil-containing zone, where direct mixing with the hydrocarbons located in this zone takes place. In this alternative, it is advantageous to convey fluid through the at least one second borehole while injecting the liquid into the at least one first borehole of the hydrocarbon reservoir. This procedure has the advantage that a better dispersion of the injected liquid is achieved from the lower area of the oil-containing zone to the upper area of the oil-containing zone and the production of hydrogen becomes more efficient.

The hydrocarbon reservoir can be a fossil hydrocarbon reservoir, i.e. a deposit of fossil hydrocarbons, e.g. a fossil petroleum deposit or fossil natural gas deposit. The hydrocarbon reservoir is preferably an (already) exhausted fossil hydrocarbon deposit (e.g. an exhausted fossil petroleum deposit or fossil natural gas deposit), since in such deposits it is economically worthwhile to convert remaining hydrocarbons located in the deposit (mainly heavy oils and light oils) into hydrogen. Fossil oil deposits with a (primary) gas cap (e.g. fossil oil deposits that have not yet been extracted) are also suitable because the gas in the (primary) gas cap is located above the oil-containing zone of the carbon reservoir. On the one hand, hydrogen-containing gas can be conveyed (by special technical devices, e.g. a hydrogen filter) directly from the (primary) gas cap and/or from a (secondary) gas cap that forms during the method according to the invention. On the other hand, hydrogen-containing liquid (i.e. hydrogen dissolved in the reservoir water) can be obtained from a lower area of the oil-bearing zone in which there is little to no gas that differs from hydrogen. Deposits of fossil hydrocarbons usually already contain microorganisms that are capable of converting hydrocarbons into hydrogen. Adding such microorganisms to fossil hydrocarbon reservoirs is therefore not absolutely necessary, but can be advantageous in order to increase the efficiency of hydrogen conversion.

In a preferred embodiment of the method, for a period of at least one month, optionally at least half a year or Year, incubated before the at least one first borehole and / or the at least one second borehole of the hydrocarbon reservoir is opened and the hydrogen-containing fluid is pumped. The longer the incubation, the greater the amount of hydrogen obtained.

The hydrocarbon reservoir may include at least a third borehole extending from a surface of the hydrocarbon reservoir into a water zone of the hydrocarbon reservoir. The at least a third borehole allows water to be pumped from the water zone of the carbon reservoir (reservoir water) to the surface. The advantage here is that not only hydrogen located above the water zone can be pumped out of the carbon reservoir, but also (dissolved) hydrogen that is (already) in the water zone of the hydrocarbon reservoir. This allows the overall hydrogen yield to be increased. Apart from that, the at least a third well allows water samples to be taken from the water zone of the hydrocarbon reservoir and analyzed, which allows optimization of the reaction conditions for the reaction of hydrocarbon to hydrogen and can improve the efficiency of hydrogen production. For example, the water can be examined for its salt content in order to select the at least one surfactant in such a way that salt formation of the at least one surfactant is suppressed or completely prevented. In addition, the at least one third borehole basically allows water to circulate from the hydrocarbon reservoir to the surface of the hydrocarbon reservoir and back into the hydrocarbon reservoir, which ensures the already very good mixing of the injected liquid (and thus the ingredients contained therein) with the substances in the hydrocarbon reservoir can be further improved by the location of the injection of the liquid in the upper area of the oil-containing zone and the help of gravity. This allows the efficiency of hydrogen production to be increased even further, even if the process becomes a little less economical due to the additional energy input.

The amount of injected liquid can be determined empirically (e.g. through data on the nature of the water in the water phase) or via a simulation of the nature of the carbon reservoir. The upper region of the oil-bearing zone of the hydrocarbon reservoir may be a region of the oil-bearing zone extending a certain length from an uppermost point of the oil-bearing zone in a direction along gravity to a lowermost point of the oil-bearing zone, the lowermost point being the oil-containing zone represents the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir, the specific length being a maximum of 50%, preferably a maximum of 40%, particularly preferably a maximum of 30%, very particularly preferably a maximum length 20%, in particular a length of a maximum of 10%, of a total length of the oil-containing zone from the highest point of the oil-containing zone to the lowest point of the oil-containing zone. The smaller the distance of the upper region from the uppermost point of the oil-containing zone, the higher the injection of the liquid into the oil-containing zone of the hydrocarbon reservoir can take place and/or the delivery of hydrogen-containing fluid can take place. An injection at a higher point has the advantage that the water and the surfactant come into contact with the largest possible volume of the oil-containing zone purely through gravity, even without energy-intensive mixing, and oil is efficiently dispersed in water with the help of the surfactant. Microorganisms present in the hydrocarbon reservoir and capable of converting hydrocarbons to hydrogen can absorb and metabolize the dispersed oil more efficiently, resulting in a more efficient conversion of hydrocarbons to hydrogen.

The lower region of the oil-bearing zone of the hydrocarbon reservoir may be a region of the oil-bearing zone extending a certain length from a lowest point of the oil-bearing zone in a direction against gravity to an uppermost point of the oil-bearing zone, the lowest point being the oil-containing zone represents the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir, the specific length being a maximum of 40%, preferably a maximum of 30%, particularly preferably a maximum of 20%, very particularly preferably a maximum of 40% 10%, in particular a length of a maximum of 5%, of a total length of the oil-containing zone from the lowest point of the oil-containing zone to the highest point of the oil-containing zone. The smaller the distance of the lower area from the lowest point the oil-containing zone, the deeper the injection of the liquid can take place into the oil-containing zone of the hydrocarbon reservoir and/or the pumping of hydrogen-containing fluid can take place. Pumping at a deeper point has the advantage that hydrogen-containing fluid can be pumped close to the place where it is created. This prevents hydrogen in the hydrogen-containing fluid from being lost through possible conversion processes within the hydrocarbon reservoir before it is removed, resulting in more efficient recovery of hydrogen.

The at least one first borehole and/or at least one second borehole in the hydrocarbon reservoir can be or will be arranged vertically at least in some areas, the vertical arrangement referring to an arrangement along gravity and wherein a vertical arrangement means an arrangement which is of a strictly vertical arrangement at a maximum angle of 20°.

Furthermore, the at least one first borehole and / or at least one second borehole in the hydrocarbon reservoir can be or will be arranged horizontally at least in some areas, the horizontal arrangement referring to an arrangement perpendicular to gravity and wherein a horizontal arrangement means an arrangement that is influenced by a strictly horizontal arrangement at a maximum angle of 20°.

The at least one surfactant in the liquid used can be contained in the liquid in an amount of at least 5 g/l. In carbonate hydrocarbon reservoirs, a higher concentration may be necessary due to adsorption (e.g. at least 10 g/l). Furthermore, it is advantageous to prevent the at least one surfactant from adsorbing on the formation material of the hydrocarbon reservoir. In principle, advantageous concentrations of the at least one surfactant can be determined from simulations and/or from core tests and/or literature reports on the nature of the hydrocarbon reservoir.

It is preferred that the at least one surfactant in the liquid used is contained in the liquid in a maximum amount that allows growth of Microorganisms capable of converting hydrocarbons into hydrogen are not affected.

The at least one surfactant in the liquid used can be selected from the group consisting of anionic surfactants, cationic surfactants, zwitterionic surfactants (amphoteric surfactants), non-ionic surfactants and combinations thereof, with the at least one surfactant preferably being selected from the group consisting of zwitterionic surfactants, nonionic surfactants and combinations thereof. Non-ionic surfactants or zwitterionic surfactants are preferred because they have lower toxicity towards microorganisms than anionic or cationic surfactants. Consequently, these surfactants can be used in a higher concentration without being toxic to microorganisms that convert hydrocarbons into hydrogen. Non-ionic surfactants are particularly preferred because they can be used regardless of the nature of the water in the hydrocarbon reservoir. For example, in hydrocarbon reservoirs with a high salt content in the water phase, non-ionic surfactants do not show any salt formation, which can weaken the effect of the at least one surfactant.

The liquid used in the process can be injected at a pressure in the range from 20 to 350 bar, preferably 25 to 300 bar. This pressure range represents an optimum because it cannot be injected above a fracking pressure and injection below a reservoir pressure is not possible.

According to the invention, the liquid used in the process is at a liquid temperature in the range from 40 ° C to <120 ° C, preferably a liquid temperature in the range from 40 ° C to 115 ° C, particularly preferably a liquid temperature in the range from 50 ° C to 110 ° C, in particular a liquid temperature in the range from 60 °C to 110 °C. The higher the temperature, the stronger the growth of microorganisms is initially stimulated (ie after the process has started), which convert hydrocarbons into hydrogen, which can increase the yield of hydrogen in a certain period of time and thus the efficiency of hydrogen production. Above a temperature of 120°C, no microbacterial activity is expected in the hydrocarbon reservoir. The liquid used in the process may also contain a carbohydrate source which promotes the growth of microorganisms capable of converting hydrocarbons into hydrogen. This embodiment can be advantageous for stimulating the growth of these microorganisms initially (ie after starting the process), whereby the yield of hydrogen can be increased in a certain period of time and thus the efficiency of hydrogen production. Furthermore, there is the possibility that these microorganisms metabolize the carbohydrate source into hydrogen, which can also increase the overall yield of hydrogen produced via the process.

The carbohydrate source is preferably selected from the group consisting of industrial sugar, molasses and combinations thereof. The advantage of using such carbohydrate sources is that they are inexpensive and available in large quantities. For example, if glucose were used as a carbohydrate source, the process would be significantly less economically feasible because glucose is a relatively expensive carbohydrate source.

The carbohydrate source can be present in the liquid used in a maximum amount of 100 g/l. A quantity of more than 100 g/l is disadvantageous because the viscosity of the liquid used would be very high in this case, which would make the injection of the liquid more energy-intensive (e.g. due to higher pressure losses) and more prone to errors (e.g. danger of clogging the at least one first Borehole, at least a second borehole, production lines and/or pumps).

The liquid used in the process may also contain a source of amino acids that promote the growth of microorganisms capable of converting hydrocarbons into hydrogen. This embodiment is advantageous if the water within the oil-containing zone of the hydrocarbon reservoir is poor in amino acids essential for the microorganisms capable of converting hydrocarbons into hydrogen. The liquid used in the process may further contain at least one type of microorganism, optionally several types of microorganisms, which are suitable for converting hydrocarbons into hydrogen. This embodiment is advantageous if the hydrocarbon reservoir has no or only a very low concentration of microorganisms that are suitable for converting hydrocarbons into hydrogen. However, this embodiment can also be advantageous if the hydrocarbon reservoir already has a high amount of such microorganisms, since in this case too, a further increase in the amount of microorganisms (or the addition of other types of microorganisms that convert hydrocarbons into hydrogen at a higher conversion rate ) can increase the efficiency of converting hydrocarbons into hydrogen.

The at least one type of microorganism is preferably a microorganism selected from the group consisting of thermophilic microorganisms, particularly preferably selected from the group consisting of thermophilic bacteria, most preferably selected from the group consisting of Bacteroidetes, Firmicutes, Spirochaete, Clostridia and Syntrophus. These microorganisms have proven to be particularly efficient in converting hydrocarbons into hydrogen.

Furthermore, the at least one type of microorganism can be present in the liquid used in the process in an amount of at least ^{10 10} cells/l, preferably at least 10 ¹¹ cells/l, very particularly preferably at least 5-10 ¹¹ cells/l. A limiting factor here can be a reduction in permeability in the area around the at least one first borehole.

In the method, while injecting the fluid into the at least one first borehole of the hydrocarbon reservoir, fluid may be produced through the at least one second borehole. This procedure has the advantage that better dispersion of the injected liquid is achieved.

The extraction of hydrogen from the hydrogen-containing fluid may include or consist of one of the following steps: Produced hydrogen-containing fluid (preferably hydrogen-containing gas) is reacted in a catalytic or non-catalytic process of steam reforming and water gas shift reactions, with the resulting CO2 preferably being fed into the at least one first borehole of the hydrocarbon reservoir and /or is injected into at least a second well of the hydrocarbon reservoir; or

Produced hydrogen-containing fluid (preferably hydrogen-containing gas) is passed through at least one hydrogen filter, wherein the at least one hydrogen filter is preferably arranged in the at least one first and/or in the at least one second borehole, in particular at a hydrocarbon reservoir-side end thereof .

In the method, after injecting the liquid into the at least one first borehole, a mixture of water vapor and carbon monoxide can be injected into the at least one first and/or into the at least one borehole.

Furthermore, in the method, the at least one first borehole and/or the at least one second borehole can be controlled for selective injection and/or selective production.

In addition, in the process, at least a portion of the hydrogen-containing gas produced can be used for methanol synthesis.

Apart from this, the substances produced in the process of producing hydrogen can be used to generate heat and/or electricity.

In addition, in the method, exhaust gases from power plants and/or other surface processes can be injected into the at least one first borehole and/or the at least one second borehole.

In the method, fluid can be conveyed from the at least one first borehole and/or the at least one second borehole and examined for microorganisms present therein. A selection of microorganisms can take place that have a particularly high efficiency in the Show conversion of hydrocarbons into hydrogen. These microorganisms can in turn be specifically added to the liquid that is injected into the at least one first borehole of the hydrocarbon reservoir, the microorganisms optionally being propagated and/or activated beforehand. This can increase the efficiency of the process.

According to the invention, a system for obtaining hydrogen from a hydrocarbon reservoir is further provided, comprising or consisting of: a) a hydrocarbon reservoir which has an oil-containing zone with a mobile water phase, the hydrocarbon reservoir having at least one first borehole which extends from a surface of the hydrocarbon reservoir extends to an upper region of the oil-containing zone, to an upper region of the oil-containing zone, or to a lower region of the oil-containing zone, b) a liquid source with a liquid that contains or consists of water and at least one surfactant; c) a first conveying means connected to the at least one first borehole, the system being adapted to close and open the at least one first borehole, the first conveying means being adapted to transfer liquid from the liquid source into the at least one first to inject borehole; d) a second production means which is connected to the at least one first borehole and/or to at least one second borehole, wherein the at least one second borehole of the hydrocarbon reservoir extends from a surface of the hydrocarbon reservoir to over an upper region of the oil-containing zone or into extends a lower region of the oil-containing zone, wherein the system is suitable for closing and opening the at least one first borehole and/or the at least one second borehole, wherein the second conveying means is suitable for supplying a hydrogen-containing fluid from the hydrocarbon reservoir support financially; e) a means for obtaining hydrogen from a hydrogen-containing fluid; f) a control unit configured to cause the first delivery means to supply liquid from the liquid source at a liquid temperature in the range of 40 ° C to <120 ° C into the at least one first borehole, to close the at least one first borehole and the at least one second borehole (preferably to close all boreholes of the hydrocarbon reservoir of the plant) and after a period of at least two weeks to cause the second funding means to open the at least one first borehole and / or the at least one second borehole and to promote a hydrogen-containing fluid, and to cause the means for producing hydrogen to produce hydrogen from the hydrogen-containing fluid win.

The plant has the advantage that it allows economical and efficient extraction of hydrogen on an industrial scale from a hydrocarbon reservoir, in particular from an (already) exhausted fossil hydrocarbon deposit.

The hydrocarbon reservoir of the plant can be a fossil hydrocarbon reservoir, i.e. a deposit of fossil hydrocarbons, e.g. a fossil petroleum deposit or fossil natural gas deposit. The hydrocarbon reservoir is preferably an (already) exhausted fossil hydrocarbon deposit (e.g. an exhausted fossil petroleum deposit or fossil natural gas deposit), since in such deposits it is economically worthwhile to convert remaining hydrocarbons located in the deposit (mainly heavy oils and light oils) into hydrogen. Fossil oil deposits with a gas cap (e.g. fossil oil deposits that have not yet been extracted) are also suitable because the gas in the gas cap is located above the oil-containing zone of the carbon reservoir.

The control unit of the system can be configured to cause the second funding means to open the at least one first borehole and/or the at least one second borehole and to supply hydrogen-containing fluid only after a period of at least one month, optionally at least half a year or year support financially.

The hydrocarbon reservoir of the facility may include at least a third well extending from a surface of the hydrocarbon reservoir extends into a water zone of the hydrocarbon reservoir. The at least a third borehole allows, among other things, water to be pumped from the water zone of the carbon reservoir (deposit water) to the surface.

The control unit of the system can be configured to determine the amount of injected liquid empirically (e.g. through data on the nature of the water in the water phase) or to determine the nature of the hydrocarbon reservoir via a simulation.

The upper region of the oil-bearing zone of the hydrocarbon reservoir of the plant may be a region of the oil-bearing zone which extends a certain length from an uppermost point of the oil-bearing zone in a direction along gravity to a lowermost point of the oil-bearing zone, the lowermost Point of the oil-containing zone represents the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir, the specific length being a maximum of 50%, preferably a maximum of 40%, particularly preferably a maximum of 30%, very particularly preferably a length of a maximum of 20%, in particular a length of a maximum of 10%, of a total length of the oil-containing zone from the highest point of the oil-containing zone to the lowest point of the oil-containing zone.

The lower region of the oil-bearing zone of the hydrocarbon reservoir of the plant may be a region of the oil-bearing zone which extends a certain length from a lowest point of the oil-bearing zone in a direction against gravity to an uppermost point of the oil-bearing zone, the lowest Point of the oil-containing zone represents the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir, the specific length being a maximum of 40%, preferably a maximum of 30%, particularly preferably a maximum of 20%, very particularly preferably a length of a maximum of 10%, in particular a length of a maximum of 5%, of a total length of the oil-containing zone from the lowest point of the oil-containing zone to the highest point of the oil-containing zone. The at least one first borehole and/or at least one second borehole in the hydrocarbon reservoir of the plant can be arranged vertically at least in some areas, the vertical arrangement referring to an arrangement along the force of gravity and wherein a vertical arrangement means an arrangement which is of a strictly vertical arrangement at a maximum angle of 20°.

Furthermore, the at least one first borehole and / or at least one second borehole in the hydrocarbon reservoir of the system can be or will be arranged horizontally at least in some areas, the horizontal arrangement referring to an arrangement perpendicular to gravity and wherein a horizontal arrangement means an arrangement which deviates from a strictly horizontal arrangement at a maximum angle of 20°.

The at least one surfactant in the liquid of the liquid source can be contained in the liquid in an amount of at least 5 g/l.

In a preferred embodiment, the at least one surfactant in the liquid of the liquid source is contained in the liquid in a maximum amount that does not impair the growth of microorganisms that are suitable for converting hydrocarbons into hydrogen.

The at least one surfactant in the liquid of the liquid source can be selected from the group consisting of anionic surfactants, cationic surfactants, zwitterionic surfactants, non-ionic surfactants and combinations thereof, wherein the at least one surfactant is preferably selected from the group consisting of zwitterionic surfactants, non-ionic surfactants and combinations thereof.

The control unit of the system can be configured to cause the conveying means to inject liquid from the liquid source at a pressure in the range of 20 to 350 bar, preferably 25 to 300 bar.

According to the invention, the control unit of the system is configured to cause the conveying means to draw liquid from the liquid source in the event of a liquid temperature in the range from 40 ° C to <120 ° C, preferably a liquid temperature in the range from 40 ° C to 115 ° C, particularly preferably a liquid temperature in the range from 50 ° C to 110 ° C, in particular a liquid temperature in the range from 60 ° C to 110 °C.

The liquid of the liquid source of the plant may also contain a source of carbohydrates which promotes the growth of microorganisms capable of converting hydrocarbons into hydrogen.

The carbohydrate source may be selected from the group consisting of industrial sugar, molasses and combinations thereof.

In addition, the carbohydrate source can be present in the liquid of the liquid source in an amount of a maximum of 100 g/l.

The liquid of the plant's liquid source may also contain amino acids that promote the growth of microorganisms capable of converting hydrocarbons into hydrogen.

The liquid may further contain at least one type of microorganism, optionally several types of microorganisms, capable of converting hydrocarbons into hydrogen.

The at least one type of microorganism can be a microorganism selected from the group consisting of thermophilic microorganisms, particularly preferably selected from the group consisting of thermophilic bacteria, most preferably selected from the group consisting of Bacteroidetes, Firmicutes, Spirochaete, Clostridia and Syntrophus.

In addition, the at least one type of microorganism can be present in the liquid of the liquid source in an amount of at least 10 ¹⁰ cells/l, preferably at least 10 ¹¹ cells/l, most preferably at least 5-10 ¹¹ cells/l. A limiting factor here can be a reduction in permeability in the area around the at least one first borehole. The means for obtaining hydrogen from hydrogen-containing fluid (e.g. hydrogen-containing gas) may be suitable for producing hydrogen-containing fluid (e.g. hydrogen-containing gas) in a catalytic or non-catalytic process of steam reforming and water gas shift reaction - nen to react, wherein the system is preferably configured to inject the resulting CO2 into the at least one first borehole of the hydrocarbon reservoir and / or into at least one second borehole of the hydrocarbon reservoir.

Furthermore, the means for obtaining hydrogen from hydrogen-containing fluid (e.g. hydrogen-containing gas) can contain or consist of at least one hydrogen filter, wherein the at least one hydrogen filter is preferably arranged in the at least one first and/or in the at least one second borehole , particularly at a hydrocarbon reservoir-side end thereof.

The system can be suitable for injecting a mixture of water vapor and carbon monoxide into the at least one first and/or into the at least one borehole after injecting the liquid. The control unit is preferably configured to cause the first funding means to carry out this injection.

The system can be suitable for this purpose, preferably the control unit of the system is configured to control the at least one first borehole and/or the at least one second borehole for selective injection and/or selective production.

The system can be suitable for using at least a portion of the hydrogen-containing gas produced for methanol synthesis. This allows the necessary reinjection amount to be reduced.

In addition, the system can be suitable for using materials produced during hydrogen production to generate heat and/or electricity.

Apart from that, the system can be suitable for exhaust gases from power plants and/or other surface processes into the at least one first borehole and/or the at least one second borehole. After gasification, the hydrocarbon reservoir has good flow properties for future injections. Another advantage is that the yield of hydrogen (and also methane) can be increased and unwanted exhaust gases from power plants and/or other surface processes can be stored in the hydrocarbon reservoir.

The system can be suitable for conveying fluid from the at least one first borehole and/or the at least one second borehole and for examining it for microorganisms present therein. Furthermore, the system can be suitable for selecting microorganisms that show a particularly high efficiency in the conversion of hydrocarbons into hydrogen. The system can further be configured, preferably caused by a control unit of the system, to add these microorganisms to the liquid that is injected into the at least one first borehole of the hydrocarbon reservoir, wherein the system is optionally configured to propagate and/or increase the microorganisms beforehand activate. This can increase the efficiency of the system.

The system according to the invention is preferably designed to carry out the method according to the invention. The control unit of the system can be configured to initiate the necessary steps to be carried out.

The use of the system according to the invention for producing hydrogen from a hydrocarbon reservoir is also proposed.

The subject matter according to the invention will be explained in more detail using the following figures and the following example, without wishing to limit it to the specific embodiments shown here.

Figure 1 shows schematically an example of a method according to the invention. The hydrocarbon reservoir 1 here has a first borehole 2 and a second borehole 3. In this example, a liquid is injected via the first borehole 2 of the hydrocarbon reservoir into an upper region of an oil-containing zone 5 with a water phase of the hydrocarbon reservoir 1 Contains or consists of water and at least one surfactant. The drill holes 2, 3 are then closed and incubated for at least two weeks. During the incubation of at least two weeks, hydrogen is formed in the water phase within the oil-containing zone 5. After incubation, the second borehole 3 is opened and hydrogen-containing fluid is conveyed to the surface of the hydrocarbon reservoir 1 via the second borehole 3, which is located in a lower region of the oil-containing zone 5 directly above a water zone 6 of the hydrocarbon reservoir 1. In this case, the first borehole 2 and the second borehole 3 are arranged horizontally in the oil-containing zone 5 of the hydrocarbon reservoir 1, which allows better development of the hydrocarbon reservoir 1, ie enables more efficient production of hydrogen.

Figure 2 shows schematically another example of a method according to the invention. The hydrocarbon reservoir 1 here has a first borehole 2, a second borehole 3 and a further second borehole 4. In this example, a liquid which contains or consists of water and at least one surfactant is injected via the first borehole 2 of the hydrocarbon reservoir into an upper region of an oil-containing zone 5 with a water phase of the hydrocarbon reservoir 1. Drill holes 2, 3, 4 are then closed and incubated for at least two weeks. During the incubation of at least two weeks, hydrogen is formed in the water phase within the oil-containing zone 5. After incubation, the second borehole 3 and the further second borehole 4 are opened and hydrogen-containing fluid is supplied via the two second boreholes 3, 4, which are located in a lower region of the oil-containing zone 5 directly above a water zone 6 of the hydrocarbon reservoir 1 the surface of the hydrocarbon reservoir 1 is promoted. In this case, the first borehole 2 and the two second boreholes 3, 4 are arranged vertically in the oil-containing zone 5 of the hydrocarbon reservoir 1, which is associated with a somewhat lower efficiency in the production of hydrogen.

Figure 3 shows schematically another example of a method according to the invention. The hydrocarbon reservoir 1 has a first borehole 2 here. In this example, the first borehole 2 of the hydrocarbon reservoir over an upper region of an oil-containing zone 5 with a water phase Hydrocarbon reservoir 1, ie in a gas cap area 8 of the hydrocarbon reservoir, which is or is formed by an already existing (primary) gas cap and / or by a (secondary) gas cap created during the process, a liquid is injected which contains water and at least one surfactant or consists of it. The first borehole 2 is then closed and incubated for at least two weeks. During the incubation of at least two weeks, 8 hydrogen is formed in the gas cap area. After incubation, the first borehole 2 is opened and hydrogen-containing fluid (here: hydrogen-containing gas) is conveyed to the surface of the hydrocarbon reservoir 1 via the first borehole 2. In this case, the first borehole 2 is arranged horizontally in the gas cap area 8 of the hydrocarbon reservoir 1, which allows better development of the hydrocarbon reservoir 1, ie enables more efficient production of hydrogen.

Figure 4 shows schematically another example of a method according to the invention. The hydrocarbon reservoir 1 here has a first borehole 2 and a second borehole 3. In this example, a liquid which contains or consists of water and at least one surfactant is injected via the first borehole 2 of the hydrocarbon reservoir into an upper region of an oil-containing zone 5 with a water phase of the hydrocarbon reservoir 1. The drill holes 2 and 3 are then closed and incubated for at least two weeks. During the incubation of at least two weeks, hydrogen is formed in the gas cap area 8 of the hydrocarbon reservoir 1. After incubation, the second borehole 3 is opened and hydrogen-containing fluid (here: hydrogen-containing gas) is conveyed to the surface of the hydrocarbon reservoir 1 via the second borehole 3, which is located in the gas cap area of the hydrocarbon reservoir 1. In this case, the first borehole 2 and the second borehole 3 are arranged horizontally in the oil-containing zone 5 of the hydrocarbon reservoir 1 or in the gas cap area 8 of the hydrocarbon reservoir, which allows better development of the hydrocarbon reservoir 1, ie enables more efficient production of hydrogen. Example 1 - Injection into and extraction from the oil-containing zone with a water phase

The following is an application example for a depleted petroleum deposit. A bore completion of the variant shown in Figure 1 is assumed.

The following steps would then be required:

1. Providing a hydrocarbon reservoir having a water zone and an oil-bearing zone having a mobile water phase located on the water zone, the hydrocarbon reservoir having a first wellbore extending from a surface of the hydrocarbon reservoir to an upper portion of the oil-bearing zone and a second Has a borehole that extends from a surface of the hydrocarbon reservoir to a lower region of the oil-bearing zone.

2. Injecting a liquid containing or consisting of water and at least one surfactant into the at least one first borehole. The optimal amount of liquid for the reactions can be calculated in advance. For this purpose, it is advantageous to set up a digital image (“twin”) of the hydrocarbon reservoir. What is necessary is a water volume that corresponds to approx. 5-10% of the porosity of the hydrocarbon reservoir (i.e. the gas volume of the hydrocarbon reservoir). The selection of the at least one surfactant can be based on the in the hydrocarbon reservoir present formation material or the composition of the water phase. This also applies to other components of the liquid such as the choice of carbohydrates, the choice of amino acids and / or the choice of certain types of microorganisms that are used to convert hydrocarbons to hydrogen are suitable.

3. Plugging the at least a first and at least a second well of the hydrocarbon reservoir.

4. Incubate for a period of at least two weeks. 5. Production of hydrogen-containing fluid through the at least a second borehole of the hydrocarbon reservoir. A hydrogen-containing liquid can be conveyed or a hydrogen-containing gas can be conveyed, whereby hydrogen can be enriched in the hydrogen-containing gas by in-situ filtering of the hydrogen-containing gas.

Example 2 - Injection into and delivery from the gas cap area

The following is an application example for a depleted petroleum deposit. A bore completion of the variant shown in Figure 3 is assumed.

The steps are as follows:

1. Providing a hydrocarbon reservoir that has a mobile water phase in the oil-containing zone, the hydrocarbon reservoir having a first borehole that extends from a surface of the hydrocarbon reservoir to over an upper region of the oil-containing zone, i.e. extends into a gas cap region of the hydrocarbon reservoir, which is or will be formed by an already existing (primary) gas cap and/or by a (secondary) gas cap created during the process.

2. Injecting a liquid containing or consisting of water and at least one surfactant into the at least one first borehole. The optimal amount of liquid for the reactions can be calculated in advance. For this purpose, it is advantageous to build a digital image (“twin”) of the hydrocarbon reservoir. What is necessary is a water volume that corresponds to approximately 5-10% of the porosity of the hydrocarbon reservoir (ie the gas volume of the hydrocarbon reservoir). The selection of the at least one surfactant can be based on the in the hydrocarbon reservoir present formation material or the composition of the water phase. This also applies to other components of the liquid such as the choice of carbohydrates, the choice of amino acids and / or the choice of specific types of microorganisms that are suitable for converting hydrocarbons to hydrogen.

3. Closing the at least one first borehole of the hydrocarbon reservoir.

4. Incubate for a period of at least two weeks.

5. Production of hydrogen-containing fluid through the at least one first borehole of the hydrocarbon reservoir. A hydrogen-containing gas can be conveyed, whereby hydrogen can be enriched in the hydrogen-containing gas by in-situ filtering of the hydrogen-containing gas. The gas cap area can be a secondary gas cap, i.e. in this case the gas cap area would only have been created during the process by the activity of the microorganisms (e.g. bacterial activity).

Example 3 - Injection into an oil-containing zone with a water phase and delivery from the gas cap area

The following is an application example for a depleted petroleum deposit. A bore completion of the variant shown in Figure 4 is assumed.

1. Providing a hydrocarbon reservoir having a mobile water phase in the oil-bearing zone, the hydrocarbon reservoir having a first wellbore extending from a surface of the hydrocarbon reservoir to a lower portion of the oil-bearing zone and a second wellbore extending from a Surface of the hydrocarbon reservoir extends over an upper region of the oil-containing zone, i.e. extends into the gas cap region of the hydrocarbon reservoir.

2. Injecting a liquid containing or consisting of water and at least one surfactant into the at least one first borehole. The optimal amount of liquid for the reactions can be calculated in advance. Here- For this, it is advantageous to build a digital image (“twin”) of the hydrocarbon reservoir. What is necessary is a water volume that corresponds to approx. 5-10% of the porosity of the hydrocarbon reservoir (ie the gas volume of the hydrocarbon reservoir). The selection of the at least one surfactant can be based on the in the hydrocarbon reservoir or the composition of the water phase. This also applies to other components of the liquid such as the choice of carbohydrates, the choice of amino acids and / or the choice of certain types of microorganisms that are used to convert hydrocarbons to hydrogen are suitable.

4. Incubate for a period of at least two weeks.

6. Production of hydrogen-containing fluid through the at least a second borehole of the hydrocarbon reservoir. A hydrogen-containing gas can be conveyed, whereby hydrogen can be enriched in the hydrogen-containing gas by in-situ filtering of the hydrogen-containing gas. The gas cap area is a secondary gas cap, ie the gas cap area was only created by bacterial activity.

1: hydrocarbon reservoir;

2: first drill hole;

3: second drill hole;

4: another second borehole;

5: oily zone (with water phase);

6: water zone; and

7: Caprock or sealing rock of the hydrocarbon reservoir;

8: Gas cap area (formed by primary and/or secondary

gas cap).

Claims

Claims Method for obtaining hydrogen from a hydrocarbon reservoir, comprising the steps or consisting of the steps: a) using a hydrocarbon reservoir which has an oil-containing zone with a mobile water phase, the hydrocarbon reservoir having at least a first borehole extending from a surface of the Hydrocarbon reservoirs extend to an upper region of the oil-bearing zone, to an upper region of the oil-bearing zone, or to a lower region of the oil-bearing zone; b) injecting a liquid containing or consisting of water and at least one surfactant into the at least one first borehole of the hydrocarbon reservoir, the liquid being injected at a liquid temperature in the range of 40 ° C to <120 ° C; c) closing at least the at least one first borehole of the hydrocarbon reservoir; d) incubate for a period of at least two weeks; e) conveying hydrogen-containing fluid from the hydrocarbon reservoir through the at least one first borehole after opening the at least one first borehole, if the at least one first borehole extends from the surface of the hydrocarbon reservoir to over the upper region of the oil-containing zone of the hydrocarbon reservoir, and/or conveying hydrogen-containing fluid from the hydrocarbon reservoir through at least one second borehole after opening the at least one second borehole, the at least at least a second well of the hydrocarbon reservoir extends from a surface of the hydrocarbon reservoir to over an upper region of the oil-bearing zone or extends to a lower region of the oil-bearing zone; and f) recovering hydrogen from the hydrogen-containing fluid. Method according to the preceding claim, characterized in that the upper region of the oil-containing zone is a region of the oil-containing zone extending over a certain length from an uppermost point of the oil-containing zone in a direction along gravity to a lowermost point of the oil-containing zone extends, the lowest point of the oil-containing zone representing the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir, the specific length being a maximum of 50%, preferably a maximum of 40%, particularly preferably a maximum of 30%, very particularly preferably a length of a maximum of 20%, in particular a length of a maximum of 10%, of a total length of the oil-containing zone from the highest point of the oil-containing zone to the lowest point of the oil-containing zone. Method according to one of the preceding claims, characterized in that the lower region of the oil-containing zone is a region of the oil-containing zone which extends over a certain length from a lowest point of the oil-containing zone in a direction against gravity to an uppermost point of the oil-containing Zone extends, the lowest point of the oil-containing zone representing the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir, the specific length being a maximum of 40%, preferably a maximum of 30%, particularly preferably a maximum of 20%. , very particularly preferably a length of a maximum of 10%, in particular a length of a maximum of 5%, of a total length of the oil-containing zone from the lowest point of the oil-containing zone to the highest point of the oil-containing zone. 4. The method according to any one of the preceding claims, characterized in that the at least one surfactant i) is contained in the liquid in an amount of at least 5 g/l; and/or ii) is contained in the liquid in a maximum amount that does not impair the growth of microorganisms capable of converting hydrocarbons into hydrogen; and/or iii) is selected from the group consisting of anionic surfactants, cationic surfactants, zwitterionic surfactants, non-ionic surfactants and combinations thereof, wherein the at least one surfactant is preferably selected from the group consisting of zwitterionic surfactants, non-ionic surfactants and Combinations of these.

5. The method according to any one of the preceding claims, characterized in that the liquid i) is injected at a pressure in the range from 20 to 350 bar, preferably 25 to 300 bar; and/or ii) is injected at a liquid temperature in the range from 40 °C to 115 °C, particularly preferably a liquid temperature in the range from 50 °C to 110 °C, in particular a liquid temperature in the range from 60 °C to 110 °C .

6. The method according to any one of the preceding claims, characterized in that the liquid further contains a carbohydrate source which promotes the growth of microorganisms which are suitable for converting hydrocarbons into hydrogen, the carbohydrate source preferably i) being selected from the group consisting of industrial sugar, molasses and combinations thereof; and/or ii) is present in the liquid in an amount of a maximum of 100 g/l. 7. The method according to any one of the preceding claims, characterized in that the liquid further contains at least one type of microorganism, optionally several types of microorganisms, which is/are suitable for converting hydrocarbons into hydrogen, the at least one type of microorganism preferably i) is a microorganism selected from the group consisting of thermophilic microorganisms, particularly preferably selected from the group consisting of thermophilic bacteria, most preferably selected from the group consisting of Bacteroidetes, Firmicutes, Spirochaete, Clostridia and Syntrophus; and/or ii) is present in the liquid in an amount of at least ^{10 10} cells/l, preferably at least 10 ¹¹ cells/l, very particularly preferably at least 5-10 ¹¹ cells/l.

8. Plant for obtaining hydrogen from a hydrocarbon reservoir, comprising or consisting of: a) a hydrocarbon reservoir which has an oil-containing zone with a mobile water phase, the hydrocarbon reservoir having at least a first borehole extending from a surface of the hydrocarbon reservoir to over a upper region of the oil-containing zone, to an upper region of the oil-containing zone, or to a lower region of the oil-containing zone, b) a liquid source with a liquid that contains or consists of water and at least one surfactant; c) a first conveying means connected to the at least one first borehole, the system being adapted to close and open the at least one first borehole, the first conveying means being adapted to transfer liquid from the liquid source into the at least one first to inject borehole; d) a second production means which is connected to the at least one first borehole and/or to at least one second borehole, wherein the at least one second borehole of the hydrocarbon reservoir extends from a surface of the hydrocarbon reservoir to over an upper region of the oil-containing zone or into extends a lower region of the oil-containing zone, wherein the system is suitable for closing and opening the at least one first borehole and/or the at least one second borehole, wherein the second conveying means is suitable for supplying a hydrogen-containing fluid from the hydrocarbon reservoir support financially; e) a means for obtaining hydrogen from a hydrogen-containing fluid; f) a control unit configured to cause the first production means to inject liquid from the liquid source at a liquid temperature in the range of 40 ° C to <120 ° C into the at least one first well, the at least one first well and the at least close a second well and, after a period of at least two weeks, cause the second funding means to open the at least one first well if this extends from the surface of the hydrocarbon reservoir to above the upper region of the oil-bearing zone of the hydrocarbon reservoir, and / or to open the at least one second borehole and to produce a hydrogen-containing fluid, and to cause the hydrogen-containing means to recover hydrogen from the hydrogen-containing fluid. Plant according to claim 8, characterized in that the upper region of the oil-bearing zone is a region of the oil-bearing zone which extends over a certain length from an uppermost point of the oil-bearing zone in a direction along gravity to a lowest point of the oil-bearing zone , where the lowest point of the oil-bearing zone is the end of the hydrocarbon reservoir or a Represents the beginning of a water zone of the hydrocarbon reservoir, wherein the specific length is a length of a maximum of 50%, preferably a length of a maximum of 40%, particularly preferably a length of a maximum of 30%, very particularly preferably a length of a maximum of 20%, in particular a length of a maximum 10%, a total length of the oil-bearing zone from the uppermost point of the oil-bearing zone to the lowest point of the oil-bearing zone. Plant according to one of claims 8 or 9, characterized in that the lower region of the oil-containing zone is a region of the oil-containing zone which extends over a certain length from a lowest point of the oil-containing zone in a direction against gravity to an uppermost point the oil-containing zone, the lowest point of the oil-containing zone representing the end of the hydrocarbon reservoir or a beginning of a water zone of the hydrocarbon reservoir, the specific length being a maximum of 40%, preferably a maximum of 30%, particularly preferably a maximum of 40% 20%, very particularly preferably a length of a maximum of 10%, in particular a length of a maximum of 5%, of a total length of the oil-containing zone from the lowest point of the oil-containing zone to the highest point of the oil-containing zone. Plant according to one of claims 8 to 10, characterized in that the at least one surfactant i) is contained in the liquid in an amount of at least 5 g/l; and/or ii) is contained in the liquid in a maximum amount that does not impair the growth of microorganisms capable of converting hydrocarbons into hydrogen; and/or iii) is selected from the group consisting of anionic surfactants, cationic surfactants, zwitterionic surfactants, non-ionic surfactants and combinations thereof, whereby the at least At least one surfactant is preferably selected from the group consisting of zwitterionic surfactants, non-ionic surfactants and combinations thereof. Plant according to one of claims 8 to 11, characterized in that the control unit is configured to cause the conveying means to inject liquid from the liquid source i) at a pressure in the range of 20 to 350 bar, preferably 25 to 300 bar; and/or ii) at a liquid temperature in the range from 40 °C to 115 °C, particularly preferably a liquid temperature in the range from 50 °C to 110 °C, in particular a liquid temperature in the range from 60 °C to 110 °C . Plant according to one of claims 8 to 12, characterized in that the liquid further contains a carbohydrate source which promotes the growth of microorganisms capable of converting hydrocarbons into hydrogen, the carbohydrate source preferably i) being selected from the group consisting of industrial sugar, molasses and combinations thereof; and/or ii) is present in the liquid in an amount of a maximum of 100 g/l. Plant according to one of claims 8 to 13, characterized in that the liquid further contains at least one type of microorganism, optionally several types of microorganisms, which is / are suitable for converting hydrocarbons into hydrogen, the at least one type of microorganism preferably i) is a microorganism selected from the group consisting of thermophilic microorganisms, particularly preferably selected from the group consisting of thermophilic bacteria, most preferably selected from the group consisting of Bacteroidetes, Firmicutes, Spirochaete, Clostridia and Syntrophus; and or ii) present in the liquid in an amount of at least ^{10 10} cells/l, preferably at least 10 ¹¹ cells/l, very particularly preferably at least 5-10 ¹¹ cells/l. Use of the system according to one of claims 8 to 14 for producing hydrogen from a hydrocarbon reservoir.