WO2020207869A1

WO2020207869A1 - Transport of fluids by means of a multi-functional transport container

Info

Publication number: WO2020207869A1
Application number: PCT/EP2020/059190
Authority: WO
Inventors: Marc Hanebuth; Dana Berlinde Habich; Markus Ungerer
Original assignee: Siemens Aktiengesellschaft
Priority date: 2019-04-10
Filing date: 2020-04-01
Publication date: 2020-10-15
Also published as: DE102019205129A1

Abstract

The invention relates to a method for transporting fluids by means of a transport container and to a transport container. When the transport container is being filled with a first fluid via a first feed line, this causes a second fluid that is present in the tank to be forced out of the tank via a second feed line, without mixing with the incoming fluid. The transport container has a tank, which is designed as a pressure vessel and a thermal insulation layer, wherein the pressure vessel is designed to withstand a pressure that is necessary to transport the second fluid of lower density in the same tank volume as the first fluid of higher density.

Description

description

Transport of fluids using multifunctional transport containers

The present invention relates to a method for the transport of fluids by means of a transport container and a transport container.

State of the art

As part of the energy transition, the primary goal is to reduce emissions of greenhouse gases, especially carbon dioxide.

With the generation of electricity from renewable energy sources as part of the energy transition, electricity is available in such large quantities in times of plenty of sun and strong wind that there is an oversupply of electricity. There are therefore already approaches to use this excess current to produce valuable products from carbon dioxide as the starting material. Such products of value also include synthetically produced fuels, for example hydrocarbons or alcohols such as. B. methanol.

There is an oversupply of electricity especially in countries with a lot of sun, countries on the Sun Belt and in desert regions or in countries with a lot of wind, e.g. B. Tierra del Fuego. Substances that contain carbon and substances that contain hydrogen are required as starting materials for valuable materials. Water, which is often available in the form of surface water or groundwater, can generally be used as the hydrogen source. It is also possible to desalinate seawater, extract water from the air or deliver it.

The availability of carbon dioxide is typically the greater challenge: In places where cheap electrical energy is available, there is usually a lack of it Point sources of carbon dioxide such as cement works for an economically viable extraction of pure carbon dioxide and vice versa. There is therefore the problem that for carbon dioxide utilization by means of excess electricity, both are not available at the same place. Either the carbon dioxide has to be transported to the place where electricity is generated from renewable energy sources or the excess electricity has to be delivered to a carbon dioxide source.

For the transport of carbon dioxide, closed pressure vessels are currently used, in which part of the mass of carbon dioxide is in liquid form, but a considerable part of the tank volume is filled with gaseous carbon dioxide. So far, gas manufacturers have used pressure vessels in which carbon dioxide is transported at a test pressure of 250 bar. This contains the carbon dioxide to be transported with a maximum density of 750 g / l. The test pressure arises from the fact that it is to be prevented that, if the contents of the pressure vessel are heated, the resulting expansion and accordingly the pressure in the vessel could become dangerously high. There is a pressure vessel regulation, according to which a maximum of 0.75 kg of carbon dioxide per liter of bottle volume may be filled. This fill factor ensures that the pressure in the carbon dioxide bottle only reaches the test pressure of 250 bar when it is heated to 65 ° C.

It can also be stated that the fuel produced from carbon dioxide utilization can rarely be fully used at the place of its manufacture. Especially where energy transmission using power lines is not an economic option for using excess electricity or electricity from renewable energy sources in general, it is important to find a solution to use this energy source anyway and to produce fuel made from carbon dioxide, for example and transport away. Where a power line is not an economical option As a rule, transporting fuel by means of a pipeline is not an option either.

Consequently, it is technically necessary to propose an improved solution which avoids the disadvantages known from the prior art. In particular, the proposed solution should enable the economical use of electricity from renewable energy sources for chemical carbon dioxide utilization.

These objects on which the present invention is based are achieved by a method according to patent claim 1. According to the invention, a transport container according to Pa tent claims 6 is used. Advantageous embodiments of the invention are the subject of the subclaims.

Description of the invention

In the method according to the invention, a transport container is refueled with a first fluid via a first feed line, as a result of which this first fluid displaces a second fluid present in the tank via a second feed line from the tank or refueling with a second fluid via the second feed line, whereby this second fluid displaces a first fluid present in the tank from the tank via the first supply line. When the fluid present in the trans port container is displaced, no mixing with the inflowing fluid should take place. This method has the advantage that two different fluids, for example carbon dioxide and a synthetically produced fuel, can be transported to and from the same transport container and correspondingly the same transport vehicle, in particular to locations with renewable energy sources. Such a method for the delivery of the educt and delivery of the product becomes economical in that transport routes without goods to be transported are avoided. Another advantage of the process is the simultaneous loading and unloading of different fluids: When refueling with the one fluid is pushed out at the same time by displacement, the second fluid is discharged. In particular, the fluids have different densities: the fluid with the lower density is loaded and unloaded in particular through an opening higher up, while the fluid with the higher density is preferably loaded and unloaded through an opening further down on the transport container . In accordance with the invention, the first fluid has carbon (compounds) and hydrogen (compounds).

In the method according to the invention, the first fluid is in particular an energy-rich fluid and the second fluid is in particular a low-energy fluid which, when used, e.g. Combustion, the first fluid is produced.

In the method according to the invention, the first fluid has, for example, a fuel, for the production of which at least one starting material is used which results as a product of value from the electrochemical conversion of carbon dioxide. The second fluid has in particular carbon dioxide, preferably pure carbon dioxide. Carbon dioxide is preferably transported as the second fluid, which is present in a purity of at least 95%, better 99%, even better 99.5%. Examples of fuels are for example ethanol, methanol or i-octane. In general, all synthetically producible fuels can be used, for example hydrocarbons or alcohols, which have carbon dioxide as a starting material. Accordingly, in one embodiment of the invention the method comprises a first fluid which is carbon, e.g. in the form of carbon compounds, hydrogen and / or hydrogen compounds.

In the method, the tank volume of the transport container should preferably be used as completely as possible in both directions, that is to say for the delivery of the first fluid and the removal of the second fluid. If you put a certain fuel, the carbon and hydrogen is based on the assumption that carbon dioxide is converted stoichiometrically during its production, it can be determined mathematically what density the carbon dioxide should have during its transport.

A particularly advantageous combination of fluids for the method is methanol as the fuel, that is to say as the first fluid, and pure carbon dioxide as the second fluid. Accordingly, in the method, the second fluid is preferably brought to a density between 800 g / 1 and 1300 g / 1, in particular to a density between 900 g / 1 and 1200 g / 1, preferably to a density between 950 g / 1 and 1150 g / l or particularly preferably to a density between 980 g / l and 1100 g / l. This second fluid can be compressed before the transport container is refueled or during the refueling of the transport container. In an exemplary embodiment of the method, the second fluid is cooled before refueling, in particular to a temperature below 8 ° C, in particular below 6 ° C, below 0 ° C, below -5 ° C, below -10 ° C, below -15 ° C or even below -20 ° C. Depending on the target molecule of the first fluid, i.e. the fuel to be transported back, the required density and accordingly the temperature at which the second fluid, e.g. the carbon dioxide must be transported in order to correspond stoichiometrically to the amount of fuel.

An example calculation is given for the particularly preferred combination of carbon dioxide and synthetically produced methanol as fuel: If methanol has a density of 790 g / 1, a molar mass of 32.04 g / mol and contains one carbon atom per molecule, you need accordingly

24.66 mol of carbon dioxide per liter of tank volume. With a molar mass of 44 g / mol carbon dioxide, this means that the density of the transported carbon dioxide in the tank volume should be 1,086 g / 1.

In principle, when using liquid carbon dioxide, higher densities than those customary in the prior art 750 g / 1 possible. For example, liquid carbon dioxide can assume densities of more than 1,000 g / l, the actual value depending on the temperature and pressure, which dependence is shown in FIG.

The transport container according to the invention, which is expediently used in the method, has a tank which is designed as a pressure vessel, has a first feed line with a shut-off device for refueling and emptying a first fluid and a second feed line with a shut-off device for refueling and Emptying of a second fluid and a safety valve. In addition, the transport container has a thermal insulation layer and is designed so that it withstands a pressure that is necessary to transport the second lower density fluid in the same tank volume as the first higher density fluid and the first and second supply lines are arranged so that simultaneous refueling via the first supply line and emptying via the second supply line and vice versa can be carried out. For example, the feed line for the fluid with the lower density is higher than the feed line for the fluid with the higher density. It is particularly advantageous if the supply lines are attached to the floor and to the ceiling of the transport container, thereby avoiding disruptive residual contents of the fluid previously refueled. According to the invention, the first fluid has carbon (compounds) and hydrogen (compounds).

According to the calculation of the density at which the carbon dioxide should preferably be transported in order to correspond stoichiometrically to the amount of fuel resulting from it, the tank of the transport container must be designed as a pressure vessel: In particular, the tank is designed for a pressure of up to 100 bar to withstand, for example up to 90 bar, up to 80 bar, up to 70 bar, up to 65 bar, up to 60 bar, up to 55 bar, up to 50 bar, up to 40 bar, up to 30 bar or up to 20 bar. The safety valve ensures that carbon dioxide can be emitted before a pressure builds up in the tank that is above the test pressure and could therefore become dangerous.

The carbon dioxide should therefore not get too warm, because otherwise the tank would have to withstand even higher pressures. An advantageous compromise between the pressure and temperature of the fluid must be found for the transport: For this, the transport container preferably comprises a cooling device with a coolant supply line and a coolant discharge line for guiding a cooling medium, in particular with a temperature control unit. The fluid, in particular the carbon dioxide, can preferably be filled in already cooled, or it can be cooled down during the refueling process, to a target temperature of below 8 ° C, in particular below 6 ° C, below 0 ° C, below -5 ° C, below -10 ° C, below -15 ° C or below -20 ° C, cf.

Figure 2. Preferably, already cooled carbon dioxide is filled into the tank. The transport container furthermore comprises an insulation layer which, although not completely preventing the tank contents from heating up, does slow it down considerably. Above all, the insulation layer is particularly useful at times when no active cooling can take place through the operation of the cooling device, e.g. when reloading. Providing the transport container with a cooling device is, however, more effective and economical than an expensive reinforcement of the insulation. The temperature control unit includes a temperature measurement and temperature control unit which activates an active cooling process as soon as the measured temperature of the tank contents rises above a limit value. This means that the tank temperature can be kept permanently below the ambient temperature.

Alternative cooling media can be used in different embodiments of the invention: In a particularly advantageous embodiment of the invention, the transport container comprises an overflow valve and a shuttle valve, which are arranged and designed to incorporate part of the second fluid, in particular the carbon dioxide, as the cooling medium to direct the cooling device. In this way, a temperature control could be implemented which, when the temperature of the tank contents rises and the pressure in the tank increases as a result, guides the fluid through the overflow valve into the cooling device, where it acts as a coolant and contributes to the active cooling of the tank contents. It is known that the enthalpy of vaporization of carbon dioxide is exceptionally high. The carbon dioxide produced can thus be used as a cooling medium by being passed through the cooling device.

Alternatively, the transport container comprises a shuttle valve which is designed to direct ambient water as a cooling medium into the cooling device. Ambient water is to be understood as meaning, for example, sea water or river water when the transport container is transported by container ship or inland ship.

In a further alternative embodiment of the invention, the transport container comprises means for connecting the cooling device to an on-board cooling system. Such a design from the cooling device is advantageous when the transport container is transported on a land vehicle, in particular a road vehicle, for. B. a truck or semi-trailer.

A combination with the embodiment with overflow valve for cooling by overflowing carbon dioxide is particularly advantageous in order to bridge times in which no active cooling by an on-board cooling system or by ambient water is possible. This is the case, for example, when reloading or for short-term interim storage.

In a very advantageous embodiment of the transport container, it has at least one flow obstacle, in particular a plurality of plate-shaped flow obstacles arranged vertically in the tank, the first feed line being arranged at the bottom of the tank and the second feed line device is arranged on the ceiling of the tank. Alternatively, meander-shaped internals are also conceivable. The internals in the tank are designed in such a way that the flow through narrow volumes in which there is a characteristic flow profile, cf. Figure 1, forms in which a mixing of the two displacing fluids is minimized: A slight mixing of the two fluids does not represent a major disadvantage, but a larger amount should not mix, since otherwise an expensive separation could be required. The proportion of mixed fluids is below 5%, in particular below 1%. A proportion of a hydroxide in the carbon dioxide can be up to 1%. A proportion of carbon dioxide in the fuel should be well below 1%, better still below 0.1%. But the carbon dioxide would not redeem so easily either.

The flow obstacles inside the tank prevent this kind of mixing during loading and unloading.

The flow properties inside the tank, in particular along the flow obstacles, can also be advantageously influenced by coating the inside volume of the tank, in particular all surfaces of the flow obstacles. An advantageous functional inner surface coating of the tank must be selected depending on the media to be transported and the tank material used. The inner coating ensures residue-free emptying, so that fewer residues of the previously refueled medium adhere to the inner tank surface and thus less mixing of the different media occurs. Accordingly, a hydrophilic coating should be selected for non-polar media and a hydrophobic coating for polar media.

The transport container has, in particular, external dimensions that correspond to those of an ISO container. This has the advantage that it can be transported flexibly on container ships, land transport means such as trucks, semi-trailers or rail transport means. In a particularly advantageous embodiment of the invention, the transport container has external dimensions that correspond to those of an ISO container. In particular, the transport container is loaded onto a container ship, barge or land transport, in particular a road or rail transport. Road transport means a truck or a semi-trailer. This offers the advantage of flexible transport by ship, train or truck. The connections for refueling and emptying, i.e. the first and second inlet, also advantageously correspond to an ISO standard.

According to the invention, the proposed method for utilizing carbon dioxide can be integrated into a large cycle in which carbon dioxide, in particular pure carbon dioxide, is reduced to a density of at least 800 g / L, in particular at least 900 g / L, at least 950 g / L or at least 980 g / L is compressed, is transported in a variant of a transport container according to the invention, is electrochemically converted into at least one product of value at the destination, this product of value is fed to a fuel production as an educt and the fuel produced therefrom is transported in a further transport container according to the invention.

When refueling, the carbon dioxide or the fuel is displaced by the other transported goods.

Alternatively, the transport container can also be used for comparably different transport goods that are not connected to one another in the context of carbon dioxide utilization, for example working gases in general, synthesis gas and other fuels. Figure description

Examples and embodiments of the present invention will be described by way of example with reference to Figures 1 to 4 of the attached drawing:

Figure 1 shows a schematic cross-sectional drawing of a

Transport container 1 with flow obstacles 6,

FIG. 2 shows a density-temperature diagram for coals

substance dioxide C02 at different pressures,

Figure 3 shows a cross section through a Transportbehäl ter 1 with cooling device 10 and

FIG. 4 shows a cross section through a transport container 1 with the configuration that can be supplied as a cooling medium from the charged carbon dioxide CO2 to the cooling device 10 via a changeover valve 14.

In FIGS. 1, 3 and 4 each is a schematic

Drawing of a cross section through a transport container 1 is shown as it corresponds to exemplary embodiments of the invention. This has a pressure-tight tank container 4, which is completely surrounded by thermal insulation 5. The tank container 4 has at least two supply lines 2, 16 via which the fueling and emptying takes place. The tank 4 can have a functional inner surface coating 15, which is selected in particular so that it prevents excessive adhesion of the media to be transported and thus fewer residues of the previously filled medium remain in the tank and mix with the newly filled fluid. In the case of more non-polar fluids, a hydrophilic coating 15 would be selected, and in the case of more polar media, a hydrophobic coating 15 would be selected. In principle, a hydrophilic coating would be a suitable inner surface coating 15 for carbon dioxide. In addition, the coating 15 of the tank inner volume has the advantage that when the tank is being refueled and simultaneously displaced previously fueled fluids less flow-related turbulence and mixing of the two media occur.

In addition to the inner tank coating 15, the flow obstacles 6 in particular contribute to the formation of an advantageous flow profile 7: In FIG. 2, vertical plates are installed as flow obstacles 6 in the inner volume of the tank. A grid of vertical plates standing perpendicular to one another is also conceivable, in order to make the areas through which the flow is to flow even narrower and more tubular or tubular. This is particularly advantageous when the densities of the two fluids differ greatly from one another.

In the example of a transport container shown in FIG

1, the supply and discharge lines 2 and 16 are each provided with shut-off valves 3 and 8; these must be suitable for withstanding the intended pressure in the tank container 4. In addition, the bottom of the tank 17 and the top of the tank container 18 are marked, the terms bottom 17 and top 18 being based on the orientation of the transport container 1 as it would be positioned on a means of transport: The bottom 17 of the tank container 4 is positioned its lowest point, at which or in its vicinity the first feed line

2 connects to the tank container 4. The ceiling 18 of the tank 4 represents its highest point, at which or in the vicinity of which the second supply line 16 connects. The heavier fluid, i.e. the fluid with a higher density, would be pumped into the tank container 4 via the lower supply line 2 and would then displace the fluid with the lower density via the supply line 16 from the tank 4 accordingly.

In principle, meandering flow obstacles are also conceivable, which divide the volume as it were into a long tube through which the flow would flow lengthways. Such a configuration would have the advantage that the two feed lines 2 and 16 are not necessarily placed at different heights of the tank must be, since the stratification is then not vertical in the total th tank 4.

In the figure 1, a third supply or discharge line with a valve 9 is shown, which represents a safety valve that opens at a predeterminable overpressure in the tank 4 to allow a quantity of the fluid to be transported to escape to the specified Ensure maximum pressure and not exceed it.

The diagram in Figure 2 shows how the density in kg / m ³ of carbon dioxide C02 with a changed temperature, given in ° C, behaves in a range between -55 ° C to 30 ° C. This is shown for different pressures of 5 bar, 10 bar, 20 bar, 40 bar, 60 bar and 80 bar. A density-temperature-pressure range that can be realized by the transport container 4 presented in front of it is shaded. When using liquid carbon dioxide, higher densities are possible for transport than the 750 g / l customary in the prior art. Liquid carbon dioxide can have densities of over 1,000 g / 1, the actual value still depending on the temperature and pressure.

In the figure 3, a cooling device 10 is additionally shown with a supply line 11 and discharge line 12 for a coolant. It is particularly expedient to cool the fluid of lower density, which has to be transported in compressed form, even before refueling and to maintain this lower transport temperature by means of the cooling device 10 of the transport container 1. The insulation layer 5 also slows down the heating of the fluid to be transported during the trans ports. Especially during loading times or with shorter interim storage, it is possible that no active cooling can be operated via a cooling device 10. Then the insulation layer 5 is of particular importance. In particular, a control unit for temperature regulation is also provided in the cooling device 10 in order to set and maintain a desired temperature inside the tank. When Coolants, cooling water or other cooling media can be used. In particular, in the case of transport containers 1 that are transported via inland or container ships, ambient water such as sea water or river water can be passed into the cooling device 10. When transporting overland means of transport such as trucks or semi-trailers, the cooling device 10 could also be connected to an on-board cooling system.

A particularly advantageous embodiment of the cooling device 10 is shown in FIG. 4, in which the coolant supply line 11 is connected to the tank 4 via an additional connecting line 19 and an overflow valve 13. The connec tion line 19 is designed by overpressure in

To supply fluid escaping inside the tank via the overflow valve 13 to the cooling device 10. The connecting line 19 is e.g. Connected via a shuttle valve 14 to the coolant supply line 11. The overflow valve 13 can take over the function of the safety valve 9, but can also be provided in addition to this. The overflow valve 13 can branch off from the supply line 16 or also be arranged at another point of the tank 4. The overflow valve 13 is designed to remove part of the carbon dioxide when the pressure increases, for example by increasing the temperature of the internal tank volume, and to supply it to the cooling device 10, where the extraordinarily high enthalpy of vaporization of carbon dioxide itself is used to cool the remaining tank volume. At the same time, the pressure in the tank 4 is already reduced by the withdrawal. This configuration is very advantageous in order to avoid times when active cooling is not possible, e.g. B. when reloading or short-term storage to bridge.

In summary it is stated:

In the method according to the invention, a transport container 1 is used for the transport of carbon dioxide or, in general, a fluid of low density, in particular a gas. Due to a correspondingly high pressure, which the Transportbehäl ter withstands and the lowest possible temperature, which is granted by the cooling device 10 and an insulation layer 5, this fluid can be transported benefits in the liquid state, so in the highest possible density.

For the transport of different fluids there and back, a loading and unloading process for the same transport container is described, which enables the same tank to be used for another fluid of the same density without an expensive cleaning step in between, which during the refueling process the previously refueled fluid from the container repressed. Advantageously, this fluid has a higher density and is a product of value from the utilization of the transported fluid, for example a synthetically produced fuel, for the production of which educts are used that result from the electrochemical conversion of the supplied carbon dioxide, the electrochemical carbon dioxide utilization is operated in particular using excess electricity from regenerative energy sources.

For this purpose, the transport container 1 comprises built-in components which serve as flow obstacles 6 and do not prevent the two fluids from being mixed 100%, but suppress them noticeably. Particularly preferred is the combination of fluids in which the first fluid, that is to say the fluid with a higher density, represents an energy carrier which in particular comprises carbon and hydrogen, for example methanol. A low-energy reaction product is transported in as the second fluid in order to ensure a closed circuit for the energy transport, which in particular has high-purity carbon dioxide.

Claims

1. A method in which a transport container is refueled with a first fluid via a first line (2), whereby this first fluid is a second fluid in the tank (4) via a second supply line (16) from the tank (4) is displaced or a second fluid is refueled via the second feed line (16), whereby this second fluid displaces a first fluid present in the tank (4) out of the tank (4) via the first feed line (2) , the displacement of the fluid present in the transport container in each case taking place without mixing with the incoming fluid, the first fluid having carbon (compounds) and hydrogen (compounds).

2. The method according to claim 1, wherein the second fluid has carbon dioxide and the first fluid has a fuel, for the production of which at least one educt is used, which educt results as a product of value from the electrochemical conversion of the carbon dioxide.

3. The method according to any one of the preceding claims 1 to 2, in which the second fluid is cooled before refueling, in particular to a temperature below 8 ° C, in particular below 6 ° C, below 0 ° C, below -5 ° C, below -10 ° C, below -15 ° C or below -20 ° C.

4. The method according to any one of the preceding claims 1 to 3, wherein the second fluid in the tank with a density of between 800 g / L and 1300 g / L, in particular between 900 g / L and 1200 g / L, between 950 g / L and 1150 g / L or between 980 g / L and 1100 g / L.

5. Transport container (1) for fluids having a tank (4) which is designed as a pressure vessel, a first line (2) with a shut-off device (3) for refueling and emptying a first fluid and a second line (16 ) with a shut-off device (8) for the kung and emptying of a second fluid as well as a safety valve (9), also having a thermal Isolati onsschicht (5), the pressure vessel is designed to withstand ei nem pressure, which is necessary to transport the second fluid of lower density in the same tank volume as the first fluid of higher density and the first and second feed lines being arranged in such a way that simultaneous refueling via the first feed line (2) and emptying via the second feed line (16) and vice versa can be carried out, the first fluid being carbon (compounds) and hydrogen (compounds).

6. Transport container (1) according to claim 5, wherein the tank (4) for a pressure up to 100 bar, up to 90 bar, up to 80 bar, up to 70 bar, up to 65 bar, up to 60 bar, up to 55 bar, up to 50 bar , up to 40 bar, up to 30 bar or up to 20 bar.

7. Transport container (1) according to one of the preceding Ansprü che 5 or 6, comprising a cooling device (10) with a coolant supply line (11) and a coolant discharge line (12) for guiding a cooling medium, in particular with a temperature control unit.

8. Transport container according to one of the preceding claims 5 to 7, comprising an overflow valve (13) and a Wechselven valve (14), arranged and configured to direct part of the second fluid as a cooling medium in the cooling device (10).

9. Transport container (1) according to one of the preceding Ansprü che 5 to 8, comprising a shuttle valve, which is ausal tet to direct ambient water as a cooling medium in the device (10) Kühlvorrich.

10. Transport container (1) according to one of the preceding Ansprü che 7 to 9, comprising means for connecting the Kühlvorrich device (10) to an on-board cooling system. 11. Transport container (1) according to one of the preceding claims 5 to 10 comprising at least one flow obstacle (6).

12. Transport container (1) according to claim 11 with a plurality of plate-shaped Strö flow obstacles (6) arranged vertically in the tank (4), wherein the first supply line (2) on the ground

(17) of the tank (4) is arranged and the second supply line (16) is arranged on the ceiling (18) of the tank (4). 13. Transport container (1) according to one of claims 5 to 12, with a functional inner surface coating (15) of the tank (4).

14. Transport container according to one of claims 5 to 13, whose outer dimensions correspond to those of an ISO container, loaded onto a container ship or a Landtransportmit tel, in particular road transport such as semi-trailers or rail transport.