Patent Description:
The present invention relates generally to transport of fluids and more particularly to efficient and effective ways to transport CO<NUM> and hydrocarbons that reduce energy consumption and shipping costs.

Transporting carbon dioxide (CO<NUM>) or liquid hydrocarbons over long distances can be difficult due to environmental concerns and the required temperature and pressure required to safely transport the fluids. One possible way to transport CO<NUM> or liquid hydrocarbons over long distance is through the usage of semi-pressurized and refrigerated ships or carriers. Such carrier is known from document <CIT>.

Shipping using these carriers, however, can be inefficient. For instance, the CO<NUM> or hydrocarbons are shipped from a first point to a second point, but the ship typically returns to the first point with an empty load, which raises shipping costs. Additionally, the shipping of CO<NUM> and liquid hydrocarbons requires energy to be consumed at high rates.

Accordingly, there is a need for an efficient and effective ways to transport CO<NUM> and hydrocarbons that reduce energy consumption and shipping costs.

The invention is defined by the accompanied independent claim <NUM> followed by dependent claims <NUM>-<NUM>.

In a first aspect, a loading and unloading station for simultaneous unloading of a first fluid from at least one storage tank in a vessel and loading of a second fluid into a storage tank of the same vessel is provided. The loading and unloading station includes a first connector for fluid connection to the at least one storage tank for unloading the first fluid, and a source of the second fluid. The loading and unloading station also includes a second connector for fluidly connecting the source of the second fluid with the at least one storage tank of the vessel for loading the second fluid into the at least one storage tank. The loading and unloading station further includes a first thermal linkage between the first fluid being unloaded and the second fluid being loaded that facilitates heat transfer between the first fluid and the second fluid at the loading and unloading station.

In another aspect of the loading and unloading station the first fluid can comprise liquefied petroleum gas (LPG) and the second fluid can comprise CO<NUM>. In a further aspect, the first thermal linkage can comprise a heat exchanger that transfers coldness of the LPG to the CO<NUM> resulting in cooling of the CO<NUM>. In another aspect, the loading and unloading station further comprises: a CO<NUM> capture unit configured to capture CO<NUM> produced from a carbon containing source and a CO<NUM> liquefaction unit that is fluidly connected to CO<NUM> capture unit and the source of the second fluid. The CO<NUM> liquefaction unit is configured to receive the captured CO<NUM> from the CO<NUM> capture unit, and to liquefy the captured CO<NUM> to desired storage conditions and transport conditions. In a further aspect, the CO<NUM> capture unit and the CO<NUM> liquefaction unit can be a single unit.

In another aspect, the loading and unloading station further comprises a hydrogen production unit fluidly connected to the at least one storage tank for unloading the LPG. The hydrogen production unit is configured to receive the LPG from the at least one storage tank for unloading the LPG and utilize the LPG as a feed stream for producing hydrogen. In a further aspect, the CO<NUM> capture unit is operatively connected to the hydrogen production unit, and further configured to capture CO<NUM> from synthetic gas produced in the hydrogen production unit.

In another aspect, the loading and unloading station further comprises an expansion device configured to receive at least a portion of the LPG from the at least one storage tank in the vessel. The expansion device is configured to reduce a pressure of the LPG prior to its delivery to an LPG unloading unit.

In a second aspect, a loading and unloading station for sequentially unloading CO<NUM> from at least one storage tank in a vessel and for loading LPG into a storage tank of the same vessel is provided. The loading and unloading station includes an LPG production unit, an LPG storage unit, where the LPG storage unit is in fluid communication with the LPG production unit. The loading and unloading station also includes a first connector for fluid connection to the LPG storage unit for loading the LPG into the storage tank of the vessel, and a second connector for unloading the CO<NUM> into a CO<NUM> storage unit. The loading and unloading station further includes at least one of: (A) a first thermal linkage that is configured to: transfer coldness from the CO<NUM> to facilitate liquefaction of the LPG through the first thermal linkage that is associated with the LPG production unit and the CO2 storage unit; and (B) a second thermal linkage that is configured to maintain temperature of the LPG storage unit through the second thermal linkage.

In a further aspect, the loading and unloading station further includes a CO<NUM> compression unit that compresses the CO<NUM> above a predetermined pressure, and a supercritical CO<NUM> unit that receives CO<NUM> from the compression unit, whereby a high pressure, cold CO<NUM> stream is put in thermal linkage with at least one of the LPG production unit and the LPG storage unit. In a further aspect, the supercritical CO<NUM> cycle includes an internal heat exchanger, an external heat exchanger, and a CO<NUM> turbine. The internal heat exchanger is configured to heat the high pressure, cold CO<NUM> stream and transfer the high pressure, cold CO<NUM> stream to the external heat exchanger. The external heat exchanger is configured to further heat the high pressure, cold CO<NUM> stream to create a high pressure, high temperature CO<NUM> stream, and configured to transfer the high pressure, high temperature CO<NUM> stream to the CO<NUM> turbine. The CO<NUM> turbine is configured to expand the high pressure, high temperature CO<NUM> stream to generate power. In a further aspect, the loading and unloading station further includes a heat source operatively connected to the external heat exchanger via a heat linkage. The heat source provides the energy for heating the high pressure, cold CO2 stream in the external heat exchanger. In a further aspect, the high pressure, high temperature CO<NUM> stream exiting the external heat exchanger has a temperature in a range of <NUM> to <NUM>. In another aspect, the CO<NUM> compression unit compresses the CO<NUM> to a pressure in the range of <NUM> to <NUM> bar.

In a third aspect, a system for simultaneous loading and unloading of CO<NUM> and a liquid hydrocarbon is provided. The system includes a vessel comprising at least one storage tank configured to transfer the CO2 or the liquid hydrocarbon, and configured to load and unload at least one of the liquid hydrocarbon and CO2. The system also includes a first station at which the liquid hydrocarbon is produced. The first station comprises a liquid hydrocarbon loading unit, a first conduit configured to selectively connect the liquid hydrocarbon loading unit, and a CO2 unloading unit. The first station also comprises a second conduit configured to selectively connect the CO2 unloading unit to the vessel, and at least one of: (a) a first thermal linkage configured to transfer coldness from the second conduit to the first conduit to facilitate liquefaction of the liquid hydrocarbon; and (b) second thermal linkage between the first conduit and second conduit configured to cause condensation of the liquid hydrocarbon in the first conduit. The system also includes a second station at which the CO2 is collected. The second station comprises a CO2 loading unit, a third conduit configured to selectively connect the CO2 loading unit to the vessel, a liquid hydrocarbon unloading unit, and a fourth conduit configured to selectively connect the liquid hydrocarbon unloading unit to the vessel. At the first station, the vessel is configured to simultaneously unload CO2 via the CO2 unloading unit and load the liquid hydrocarbon into the at least one storage tank. At the second station, the vessel is configured to simultaneously unload the liquid hydrocarbon via the liquid hydrocarbon unloading unit and load the CO2 into the at least one storage tank.

In another aspect of the system, the second station further includes a CO<NUM> capture unit configured to capture CO<NUM> produced from a carbon containing source, and a CO<NUM> liquefaction unit fluidly connected to CO<NUM> loading unit. The CO<NUM> liquefaction unit is configured to receive the captured CO<NUM> from the CO<NUM> capture unit, and to liquefy the captured CO<NUM> to desired storage conditions and transport conditions. The second station also includes a third thermal linkage between the CO<NUM> liquefaction unit and the fourth conduit, where the third thermal linkage is configured to help CO<NUM> liquefaction.

In another aspect of the system, the first station further comprises a CO2 storage unit fluidly connected to the CO2 unloading unit and configured to receive CO2 from the CO2 unloading unit. In this aspect, the first station also comprises, a CO2 compression unit fluidly connected to the CO2 storage unit and configured to receive CO2 from the CO2 unloading unit, where the CO2 compression unit is configured to compress CO2 above a predetermined pressure. In a further aspect, the system further includes a CO2 supercritical cycle fluidly connected to the CO2 compression unit, where the CO2 supercritical cycle is configured to receive CO2 from the CO2 compression unit and generate power. In a further aspect, the vessel further includes a boil-off compression unit, a non-condensable separation unit, and a boil-off liquefaction unit. The boil-off compression unit is fluidly connected to the at least one storage tank and configured to receive a boil-off stream from the at least one storage tank comprising CO2 and non-condensable gases such as nitrogen, and compress the boil-off stream. The non-condensable (e.g., nitrogen) separation unit is fluidly connected to the boil-off compression unit and configured to receive the compressed boil-off stream, and separate the non-condensable gases from the CO2. The boil-off liquefaction unit is fluidly connected to the non-condensable separation unit and configured to receive the separated CO2, liquefy the CO2, and transfer the liquefied CO2 back to the at least one storage tank.

Additional aspects, features, and advantages of the embodiments of the present application are set forth in the following detailed description with reference to the drawing figures.

The present application describes systems and methods for efficiently transporting liquid hydrocarbons and CO<NUM> and reducing overall energy consumption of the transport scheme. Further, the present systems and methods involve thermal linkage mechanisms between the liquid hydrocarbon facilities and the CO<NUM> facilities that allows for harnessing of the "coldness" of the CO<NUM>, during at least one of and preferably both the unloading and loading process and thus additional energy savings is realized.

In one or more embodiments, the present system comprises a liquid hydrocarbon/CO<NUM> transport scheme including a first location ("Point A") having a liquid hydrocarbon loading facility and a CO<NUM> unloading facility, a second location ("Point B") having a CO<NUM> loading facility and a liquid hydrocarbon unloading facility, and a vessel (e.g., marine vehicle, land-based vehicle, such as tanker truck or a tanker railway car) configured to alternatively transfer CO<NUM> and a liquid hydrocarbon feed between the first and second locations. The liquid hydrocarbon feed can be transported via the vessel from Point A to Point B for subsequent hydrogen production at Point B. The same vessel can then transport CO<NUM> that is captured from the hydrogen production at Point B back to Point A. In one or more embodiments, the facilities at both Points A and B can comprise one or more thermal linkages (e.g., heat exchangers, heat pipes) configured to provide heat/cold integration (e.g., heat transfer, cold transfer) between the CO<NUM> facilities and the liquid hydrocarbon facilities. This energy transfer at strategic locations of the transport scheme reduces the overall energy consumption and transport costs for CO<NUM>/liquid hydrocarbon storage and transportation.

The referenced systems and methods for transporting liquid hydrocarbons and CO<NUM> are now described more fully with reference to the accompanying drawings, in which one or more illustrated embodiments and/or arrangements of the systems and methods are shown. The systems and methods of the present application are not limited in any way to the illustrated embodiments and/or arrangements as the illustrated embodiments and/or arrangements. It should be understood that the systems and methods as shown in the accompanying figures are merely exemplary of the systems and methods of the present application, which can be embodied in various forms as appreciated by one skilled in the art. Therefore, it is to be understood that any structural and functional details disclosed herein are not to be interpreted as limiting the systems and methods, but rather are provided as a representative embodiment and/or arrangement for teaching one skilled in the art one or more ways to implement the systems and methods.

<FIG> displays a diagram of an exemplary system for CO<NUM> and liquid hydrocarbon transport, which utilizes heat/cold integration of the CO<NUM> and liquid hydrocarbon facilities in accordance with one or more embodiments. The system comprises a first location, "Point A" (denoted by the dotted line), which includes a CO<NUM> loading facility and a hydrocarbon unloading facility, a second location, "Point B," (denote by the dashed line) having a hydrocarbon loading facility and a CO<NUM> unloading facility, and a vessel <NUM> configured to alternatively transfer the liquid CO<NUM> and the liquid hydrocarbons between Points A and B. It should be understood that the hydrocarbon and CO<NUM> facilities at Points A and B comprise numerous containers, pipe, pipelines, connectors, gauges, and valves, for controlling the flow, temperature, and pressure of the CO<NUM> and hydrocarbon streams, for example, as would be understood by a person of ordinary skill in the art. For example, there can be one or more docking stations (loading and unloading stations) as Points A and B that contain equipment to allow a fluid connection to be established and flow regulated for either: (<NUM>) liquid CO<NUM> downloading and liquid hydrocarbons being uploaded or (<NUM>) liquid CO<NUM> uploading and liquid hydrocarbons downloading.

While the vessel <NUM> is represented in <FIG> as a marine vessel (e.g., ship or tanker), in other embodiments the vessel can be a land-based vehicle (e.g., tanker truck or tanker car for a train), or other type of carrier configured for transporting LPG and CO<NUM>. Further, while the liquid hydrocarbon represented in the figures and described in the following description is liquefied petroleum gas (LPG), in other embodiments other types of liquid hydrocarbons can be utilized such as liquefied natural gas (LNG). As exemplified in <FIG>, the vessel <NUM> can have one or more storage containers (storage tanks) <NUM> for storing the CO<NUM> and/or the liquid hydrocarbon (e.g., LPG).

As known in the art, a typical LNG marine carrier has four to six storage tanks located along the center-line of the marine vessel. Surrounding these storage tanks is a combination of ballast tanks, cofferdams and voids so as to, in effect, provide the marine vessel a double-hull type design.

Inside each storage tank, there are typically three submerged pumps. There are two main cargo pumps which are used in cargo discharge operations and a much smaller pump which is referred to as the spray pump. The spray pump is used for either pumping out liquid LNG to be used as fuel (via a vaporizer), or for cooling down cargo tanks. It can also be used for "stripping" out the last of the cargo in discharge operations. All of these pumps are contained within what is known as the pump tower which hangs from the top of the tank and runs the entire depth of the tank. The pump tower also contains the tank gauging system and the tank filling line, all of which are located near die bottom of the tank.

In membrane-type marine vessels, there is also an empty pipe with a spring-loaded foot valve that can be opened by weight or pressure. This structure represents an emergency pump tower. In the event both main cargo pumps fail the top can be removed from this pipe and an emergency cargo pump lowered down to the bottom of the pipe. The top is replaced on the column and then the pump is allowed to push down on the foot valve and open it. The cargo can then be pumped out safely.

All cargo pumps typically discharge into a common pipe which runs along the deck of the vessel; it branches off to either side of the vessel to the cargo manifolds, which are used for loading or discharging. All cargo tank vapor spaces are linked via a vapor header which runs parallel to the cargo header. This also has connections to the sides of the ship next to the loading and discharging manifolds.

Thus, when the vessel comprises an LNG carrier, the fluid, in this case either LPG or CO<NUM> or other suitable fluid (liquid or gas) passes through cargo manifolds for the loading and unloading of the respective cargo (e.g., in this case and according to one embodiment, LPG or CO<NUM>).

With continued reference to <FIG>, beginning at Point A, an LPG stream can be produced at an LPG production unit <NUM> via fractionation of and subsequent liquefaction of gas condensates and a petroleum stream. It will be appreciated that any number of conventional techniques can be used to produce the LPG stream. The produced LPG stream can then be transported via line <NUM> (e.g., conduit, piping) to an LPG storage facility <NUM> (such as a tank), where the LPG is stored at an appropriate temperature and pressure to maintain the LPG at liquid phase. As used herein in reference to the figures, the numbered "lines" (e.g., line <NUM>) refer to a conduit or piping configured to transfer fluids, including hydrocarbons and/or CO<NUM>, between the various production, processing, and storage units of the CO<NUM> and hydrocarbon facilities.

In one or more embodiments, LPG storage facility <NUM> is maintained at a temperature between approximately -<NUM> and ambient temperature and at a pressure between approximately <NUM> bar and <NUM> bar. However, these values are only exemplary and other storage conditions can be used depending upon the type of storage facility, etc..

When the vessel <NUM> is ready for loading at Point A, the LPG stream is withdrawn from the LPG storage facility <NUM> via line <NUM> and transferred to an LPG loading facility <NUM>. The LPG stream is then transferred from the loading facility <NUM> via line <NUM> to the vessel <NUM>. In at least one embodiment, the system can further comprise a gaseous LPG line <NUM> that transfers back a portion of the LPG from the vessel to the LPG loading unit <NUM>, the LPG storage facility <NUM>, and/or the LPG production unit <NUM>. Line <NUM> is used to control the pressure in the vessel because in instances in which the system cannot accommodate the overpressure, excess LPG could be flared.

Once the LPG is loaded onto the vessel <NUM> (e.g., into the cargo tanks through the cargo manifolds), the vessel <NUM> transports the LPG from Point A (origin) to Point B (destination). The vessel <NUM> is selectively configured to maintain the LPG at a selected pressure and temperature for LPG transport, and is also configured to maintain a selected pressure and temperature for liquefied CO<NUM> transport, as discussed in further detail below.

Once the vessel <NUM> carrying the LPG has reached Point B, the LPG is unloaded from the vessel <NUM> through line <NUM> to LPG unloading unit <NUM>. After unloading, the LPG stream is then conveyed from unloading unit <NUM> to the LPG storage facility <NUM> via line <NUM>. The LPG storage facility <NUM> can be, for example, a large volume facility to control in-country LPG distribution or could be of smaller capacity, built as a buffer for the LPG unloading before transfer to an industry or network. Similar to the loading process at Point A, in one or more embodiments, the LPG storage facility <NUM> (unloading LPG storage facility) at Point B includes a gaseous LPG return line <NUM> that connects back to the vessel <NUM> to control the pressure in the LPG storage facility <NUM> and to flare or expel any excess pressure buildup in the system.

In one or more embodiments, the LPG stream can be subsequently conveyed from the storage facility <NUM> to a nearby LPG pipeline <NUM> via line <NUM>, or alternatively to another industrial facility. In at least one embodiment, after conveyance to the LPG pipeline <NUM>, the LPG stream can be fed via line <NUM> to a nearby hydrogen production facility <NUM>, where the hydrogen production facility uses the LPG stream as a feedstock to produce hydrogen. The hydrogen production unit <NUM> can be based on steam reforming, partial oxidation, auto-thermal reforming or any other technology known to those skilled in the art that can produce hydrogen from hydrocarbon feedstocks. In such units, the hydrogen is separated from the synthetic gas and fed to a hydrogen network or is consumed in a nearby industry (line <NUM>). The hydrogen production unit <NUM> can also be operatively connected to a CO<NUM> capture unit <NUM>. The CO<NUM> capture unit <NUM> is configured to capture the CO<NUM> from the synthetic gas of the hydrogen production unit <NUM> (via line <NUM>) that is usually conveyed at high pressure. In at least one embodiment, a second CO<NUM> capture unit can be present that captures CO<NUM> from a furnace flue gas (i.e., a low-pressure CO<NUM> stream) in an embodiment in which the hydrogen production unit <NUM> utilizes a steam LPG reforming process to make hydrogen. In at least one embodiment, these two CO<NUM> capture units can be combined in one single unit treating the high-pressure and the low-pressure CO<NUM> streams.

In at least one embodiment, the CO<NUM> from the hydrogen production unit <NUM> can be captured from a high-pressure reformer and the CO<NUM> capture rate can be adapted to match the maximum CO<NUM> capacity that can be transported in the LPG/CO<NUM> vessel back to Point A. In an embodiment in which CO<NUM> is needed in a local or nearby industry, the CO<NUM> capture unit can be designed and operated to capture the CO<NUM> such that a portion is transported in the vessel, and another portion is saved for use in the nearby industry (line <NUM>).

In one or more embodiments, the CO<NUM> capture unit <NUM> can be utilized to capture CO<NUM> produced from carbon containing source. For example, as shown in <FIG>, in one or more embodiments the CO2 capture unit <NUM> can be utilized to capture CO2 produced from the hydrogen production unit <NUM> and/or a nearby pipeline (line <NUM>). In other embodiments, the CO2 captured by the capture unit <NUM> can be produced from the reforming of hydrocarbons such as LPG, or from the combustion of fossil fuels or biomass. In at least one embodiment, the CO2 capture unit <NUM> can capture CO2 directly from the air. In the exemplary embodiment of <FIG>, the CO2 is produced from the hydrogen production unit that is fed with hydrocarbons (LPG or natural gas), in addition to cases where the CO2 can be captured far from the port from various sources and then transferred to the port via pipeline.

With continued reference to <FIG>, CO<NUM> captured by CO<NUM> capture unit <NUM> can then be transferred via line <NUM> to a CO<NUM> liquefaction unit <NUM> where the CO<NUM> is conditioned and liquefied to desired storage conditions and/or CO<NUM> transport conditions. In one or more embodiments, the liquefied CO<NUM> is then fed to a CO<NUM> storage facility <NUM> via line <NUM> to gather the necessary volume for loading and transport in the vessel <NUM>.

In at least one embodiment, the CO<NUM> capture unit <NUM> and the CO<NUM> liquefaction unit <NUM> can be a single unit, such as a CO<NUM> purification unit based on cold or cryogenic separation or distillation. Many configurations for CO<NUM> capture and liquefaction are known in the art for capturing CO<NUM> by separation or liquefaction as exemplified in <FIG> and as shown and described in <NPL>, doi:<NUM>/en7053484, which is hereby incorporated by reference. In such an instance, the thermal linkage <NUM> as shown in <FIG> can be operatively connected between the combined capture and liquefaction unit and the cold LPG stream at line 103A and/or the LPG storage unit <NUM>. For instance, in an embodiment in which the CO<NUM> liquefaction unit <NUM> is integrated with the CO<NUM> capture unit <NUM> as shown in <FIG>, the thermal linkage <NUM> and/or <NUM> (as shown in <FIG>) can be provided between the LPG and one or many of the internal heat exchangers or external heat exchangers H1, H2, H3, H4, H5 and H6, and/or the streams in-between them as shown in <FIG>. LPG coldness configuration can be thermally linked to any or multiple streams or heat exchangers in the CO<NUM> liquefaction unit that are at a temperature higher than the LPG stream temperature, which is generally between -<NUM> and ambient temperature.

In one or more embodiments, the thermal linkages <NUM> and <NUM> can be any mechanism known in the art for establishing thermal communication between the CO<NUM> liquefaction unit <NUM> and the LPG stream at line <NUM>/103A and/or the LPG storage unit <NUM>. For example, the thermal linkages <NUM> and/or <NUM> can comprise a heat exchanger or a thermal transfer loop that transfers the coldness of the LPG stream to the CO<NUM> liquefaction unit <NUM> such that it can contribute to the reduction of the temperature of the CO<NUM> stream and its liquefaction energy and thus functioning as a cold sink. Due to the low temperature of LPG stream, line <NUM>/103A and/or the LPG storage unit <NUM> can act as cold sink for the CO<NUM> liquefaction unit <NUM>. The thermal transfer loop can contain transfer fluid having a low freezing point, for example, and the transfer fluid can be circulated within the thermal transfer loop using a pump or other practical means. Thermal transfer of the coldness from the LPG (line <NUM>/103A and or the LPG storage unit <NUM>) to the CO<NUM> liquefaction unit <NUM> via the thermal transfer loop (thermal linkages <NUM> and <NUM>) can be accomplished in various ways known in the art, including via heat exchanger fins or coils, heat pipes, along with a suitable heat exchanger fluid for example high normal boiling point temperature hydrocarbons such as pentane, hexane, or water ethylene glycol mixtures.

In one or more embodiments, the CO<NUM> liquefaction unit <NUM> can be independent of the CO<NUM> capture unit <NUM>, as shown in <FIG>. In such an embodiment, the CO<NUM> liquefaction unit can be based on an external refrigeration system or a closed loop system such as the system presented in <FIG> and shown and described in <NPL>, which is hereby incorporated by reference. Alternatively, the CO<NUM> liquefaction unit can be based on an open loop system such as the Linde Hampson system (pictured in <FIG> and shown and described in Youngkyun Seo et al. , which is hereby incorporated by reference) and or another similar system. In the case of closed loop systems such as the example shown in <FIG>, the thermal linkage <NUM> and/or <NUM> (as shown in <FIG>) can be provided between the LPG and one or many of heat exchangers HX1, HX2, Flash cooler I, Flash cooler II, and/or the streams in-between them, and or line <NUM> as shown in <FIG>. In the case of an open system such as in <FIG>, thermal linkage <NUM> and/or <NUM> (as shown in <FIG>) can be provided between the LPG and one or many of heat exchangers: Heat exchanger I, Heat exchanger II, and/or the streams in-between them and/or line <NUM> as shown in <FIG>.

Referring again the <FIG>, in at least one embodiment, CO<NUM> can be conveyed to the CO<NUM> loading facility <NUM> through a pipeline and can be pre-conditioned. In such an embodiment, a CO<NUM> liquefaction process at unit <NUM> is still needed, however its configuration could be different from the various liquefaction units presented above. For example, <FIG> shows an optimized process configuration for pipeline CO<NUM> liquefaction as shown and described in <NPL>, which is hereby incorporated by reference. In such a configuration, thermal linkage <NUM> and/or <NUM> of the present system (as shown in <FIG>) can be provided between the LPG (line <NUM>/103A and or the LPG storage unit <NUM>) and one or many of heat exchangers HX21, HX22, HX23, HX24, and or the streams in-between them as shown in <FIG>.

Referring again to <FIG>, when the vessel <NUM> is ready to be loaded with CO<NUM>, the CO<NUM> loading facility <NUM> withdraws the CO<NUM> from the CO<NUM> storage facility <NUM> via line <NUM> and transfers it to the vessel <NUM> via line <NUM>. In at least one embodiment, a gaseous CO<NUM> return line to the CO<NUM> liquefaction unit <NUM> and/or CO<NUM> storage facility <NUM> can be utilized to control the pressure in the vessel <NUM> during loading of the CO<NUM>. If transported over long distances, the CO2 can be transported through pipelines in supercritical state. In such case, the supercritical CO2 would be liquefied before transferred to the vessel <NUM>.

In one or more embodiments, the vessel <NUM> can be configured to allow for simultaneous loading of CO<NUM> and unloading of LPG, and conversely, simultaneous loading of LPG and unloading of CO<NUM>. In such in an embodiment, at Point B the vessel <NUM> is configured to unload LPG through line <NUM> and simultaneously load the CO<NUM> through line <NUM>. In at least one embodiment in which there is simultaneous loading and unloading, the LPG unloading line <NUM> and/or line <NUM> can be in thermal linkage <NUM> with the CO<NUM> liquefaction unit <NUM> such that the coldness of the LPG stream can contribute to the reduction of the temperature of the CO<NUM> stream and its liquefaction. As expressed herein, "thermal linkage" refers to one or more heat exchangers; heat transfer through a heat pipe or through an intermediate fluid loop; heat transfer through an intermediate solid material that is heated by the hotter stream and cooled by the colder stream; or other means known to a person skilled in the art that allow for the heat transfer (or cold transfer) between two streams.

In at least one embodiment, during the unloading of LPG at Point B, all or a portion of LPG unloading line <NUM> can be fed to an expansion device <NUM> before transfer to the LPG unloading unit <NUM> via line 103A. The feeding of at least a portion of the unloaded LPG to the expansion device <NUM> reduces the pressure of the LPG as well its temperature. In one or more embodiments, line 103A is in thermal linkage (e.g., via thermal linkage <NUM>) with one or more of the following: the CO<NUM> liquefaction unit <NUM>, the CO<NUM> loading stream <NUM>, the CO<NUM> vapor stream connecting the vessel <NUM> to the CO<NUM> storage facility <NUM> or CO<NUM> liquefaction unit <NUM>, and/or the LPG storage unit <NUM>. In one or more embodiments, the thermal linkage <NUM> between line <NUM> and one or more of the above lines or units can allow the low temperature, low pressure LPG stream in line 103A to maintain its temperature. In such an embodiment, the higher temperature LPG stream (line <NUM>) can be compressed and re-liquefied before it is fed to storage.

Once CO<NUM> loading is completed, the vessel <NUM> can transport the CO<NUM> from Point B to Point A. Alternatively, the vessel <NUM> can transport all or a portion of the CO<NUM> to another land-based, on-shore or off-shore unloading point. In at least one embodiment, the CO<NUM> can be transported as a slurry which is a mix of solid CO<NUM> in suspension in liquid CO<NUM> to maximize the CO<NUM> intake and avail latent heat to curb the heat losses and boil-off of the CO<NUM> during transport.

In one or more embodiments, the vessel <NUM> can have a dedicated compression and liquefaction unit to condense the LPG boil-off during transport and another compression and liquefaction unit for the CO<NUM> boil-off liquefaction. Alternatively, the vessel <NUM> can use the same boil-off liquefaction unit for both CO<NUM> and LPG. <FIG> shows a typical LPG/CO<NUM> transport scheme having a vessel with a boil-off compression and liquefaction unit <NUM> in accordance with one or more embodiments.

A typical boil-off re-liquefaction unit for CO<NUM> is shown at <FIG> and is shown and described in <NPL>, which is hereby incorporated by reference. In certain configurations, there is no separation of the incondensable compounds from the CO<NUM>. However, as shown in <FIG>, in one or more embodiments, incondensable compounds can be separated from the CO<NUM> stream during transport on vessel <NUM>.

As exemplified in <FIG>, in one or more embodiments, the system of the present application discloses a boil-off liquefaction unit comprising a nitrogen separation unit or non-condensable separation unit <NUM>, which reduces the non-condensable gases content in the liquid CO<NUM> and reduce the energy spent for the boil-off re-liquefaction. As shown in <FIG>, the non-condensable separation unit <NUM> is shown as a nitrogen (N<NUM>) separation unit. However, it should be understood that in one or more embodiments, non-condensable gases other than nitrogen can also be separated from the CO2 in separation unit <NUM>, including but not limited O2, CO or methane. In one or more embodiments, when the vessel is transporting CO<NUM>, a boil-off stream <NUM> in the vessel is compressed in a boil-off compression unit <NUM> and fed through line <NUM> to a non-condensable separation unit <NUM> where nitrogen and other incondensable compounds are separated from the CO<NUM> stream. The separated nitrogen (N<NUM>) and incondensable compounds are removed from the separation unit <NUM> via line <NUM>. The separated CO<NUM> stream is then transferred to the boil-off liquefaction unit <NUM> where it is liquefied before being fed back to storage container <NUM> of the vessel <NUM> through line <NUM>. Accordingly, using the boil-off liquefaction and compression units and the non-condensable separation unit, the present system can purify the CO<NUM> while it is being transported on the vessel <NUM>.

Separation unit <NUM> can be based on membrane technology, adsorption technology or any other technology known in the art that can separate nitrogen and incondensable compounds from the CO<NUM> stream. Preferred embodiments for separation unit <NUM> comprise membrane technology and/or cryogenic separation. In this latter case, unit <NUM> can be a cryogenic unit that simultaneously liquefies the CO<NUM> and reject the incondensable compounds, such as the separation unit (presented in <FIG>) and shown and described in <NPL>, which is hereby incorporated by reference.

In an embodiment in which the CO<NUM> is transported from Point B to Point A, upon reaching Point A the CO<NUM> is transferred out of the vessel via line <NUM> to CO<NUM> unloading unit <NUM>, which then conveys the CO<NUM> into an intermediate CO<NUM> storage facility <NUM> via line <NUM>. After temporary storage at facility <NUM>, the CO<NUM> can be conveyed through line <NUM> to a CO<NUM> compression station (unit) <NUM>, where the CO<NUM> stream is compressed to a predetermined CO<NUM> utilization pressure or CO<NUM> pipeline pressure. In one or more embodiments, at least a portion of the compressed CO<NUM> can then be transported out of station <NUM> through line <NUM> and into a CO<NUM> pipeline <NUM>.

In one or more embodiments, point A can also comprises a supercritical CO<NUM> cycle <NUM> that is operatively connected to the CO<NUM> compression station <NUM> and/or the CO<NUM> pipeline <NUM>. At least a portion of the compressed CO<NUM> from station <NUM> can be fed to the supercritical CO<NUM> cycle <NUM> via line <NUM>.

In one or more embodiments, CO<NUM> withdrawn from the CO<NUM> storage facility <NUM> (generally operated between approximately -<NUM> and ambient temperature) is compressed in the CO<NUM> compression station <NUM> to a CO<NUM> pipeline pressure. The CO<NUM> pipeline pressure can be in the range of approximately <NUM> bar to approximately <NUM> bar, and in at least one embodiment, above <NUM> bar. In certain embodiments, at least a portion of the CO<NUM> can then be conveyed to utilization plants, sequestered underground in aquifers or geological formations, or used for enhanced oil recovery or reservoir pressurization.

In at least one of the embodiment, the CO<NUM> compression unit <NUM> compresses the CO<NUM> to a pressure above the CO<NUM> pipeline pressure (typically <NUM> to <NUM> bar) and provides at least a portion of the CO<NUM> to a supercritical CO<NUM> unit <NUM> via line <NUM> where the CO<NUM> is used as a motive fluid to produce power. An exemplary a supercritical CO<NUM> unit (e.g., supercritical CO<NUM> bottoming cycle) in accordance with one or more embodiments is provided in <FIG>.

With reference to <FIG>, in the supercritical CO<NUM> unit <NUM>, a high pressure cold CO<NUM> stream is put in thermal linkage with LPG facilities (thermal linkages <NUM> and <NUM> as shown in <FIG>) before being further heated in internal heat exchanger <NUM>. The CO<NUM> stream can then be transferred via line <NUM> to an external heat exchanger <NUM> in heat linkage <NUM> with a heat source <NUM>. Heat source <NUM> can be waste heat available in adjacent plants or heat from the utility area of the LPG production facility or any heat available from a nearby industry, for example. This heat linkage <NUM> can allow the temperature of the CO<NUM> stream exiting the external heat exchanger <NUM> at line <NUM> to reach approximately <NUM> to <NUM>. This high-pressure, high-temperature CO<NUM> stream (in line <NUM>) can then be conveyed to CO<NUM> turbine <NUM> where it is expanded to generate mechanical work and eventually electricity. In one or more embodiments, the CO<NUM> stream exiting the CO<NUM> turbine <NUM> via line <NUM> has a pressure that is just above the CO<NUM> pipeline pressure and has a temperature between approximately <NUM> and approximately <NUM>. The CO<NUM> stream in line <NUM> can then be fed back to the internal heat exchanger <NUM> where it is cooled, while heating the incoming high-pressure CO<NUM> stream from line <NUM>, and then exits heat exchanger <NUM> through line <NUM> to feed the CO<NUM> pipeline <NUM>.

In certain embodiments, other configurations for supercritical CO<NUM> cycle <NUM> can be used as are known in the art, including configurations in which there are multiple stages of compression. The system of the present application as described also allows for the heat linkage with the heat source <NUM> and thermal linkages with the LPG facilities with any of these other supercritical CO<NUM> cycle configurations that are known to those skilled in the art. In at least one embodiment, the CO<NUM> compression station <NUM> can be a multistage compression system in which a portion of the CO<NUM> is compressed to the CO<NUM> pipeline pressure and conveyed to the CO<NUM> pipeline <NUM> through line <NUM> while a remaining portion of the CO<NUM> stream is compressed to a higher pressure and fed to the supercritical CO<NUM> cycle <NUM> through line <NUM>.

In an embodiment in which the vessel <NUM> is configured to allow simultaneous loading of LPG and unloading of CO<NUM> at Point A, a thermal linkage <NUM> can exist between the CO<NUM> unloading line <NUM> and the LPG loading line <NUM> or LPG line <NUM>. The thermal linkage <NUM> allows for heat transfer between the LPG stream (typically maintained at temperature between ambient and approximately -<NUM>) and the CO<NUM> stream (typically maintained between the CO<NUM> triple point temperature [approximately -<NUM>] and +<NUM>). This heat transfer allows the LPG stream to be further cooled and stored in the vessel <NUM> at lower temperature as compared with the LPG storage facility <NUM>. Further, in at least one embodiment, the additional coldness of the LPG stream can be used for maintaining the temperature of the LPG stream at the LPG unloading location (Point B) and/or for additional energy transfer. In at least one embodiment, CO<NUM> unloading line <NUM> can be in thermal linkage with gaseous LPG line <NUM> (thermal linkage <NUM>), which allows for the condensation of the gaseous LPG, reducing the load on the LPG production unit <NUM> and/or the LPG storage facility <NUM>.

As with the thermal linkages <NUM> and <NUM> at Point B, the thermal linkages <NUM> and <NUM> can comprise one or more heat exchangers or thermal transfer loops that can contain transfer fluid having a low freezing point, for example. The transfer fluid can be circulated within the thermal transfer loop using a pump or other practical means. Thermal transfer between the LPG lines (lines <NUM> and <NUM>) and the CO<NUM> line <NUM> via the thermal transfer loop(s) (thermal linkages <NUM> and <NUM>) can be accomplished in various ways known in the art, including via heat exchanger fins or coils, heat pipes, along with a suitable heat exchanger fluid for example high normal boiling point temperature hydrocarbons such as pentane, hexane, or water ethylene glycol mixtures.

In at least one embodiment, two vessels <NUM> can be used for simultaneously loading/unloading of the liquid hydrocarbon (e.g., LPG) and the CO2, and the vessels can be linked together via one or more thermal linkages. For example, a first vessel can arrive and start unloading the LPG at point B, and a second vessel can arrive few hours or a day later (depending on the amount of fluid to unload) to unload its LPG cargo as well. As the second vessel is unloading the LPG, the storage tanks of the first vessel can undergo purging and conditioning for receiving CO2. As such, via a thermal linkage between the second vessel and the first vessel, the coldness of the LPG being offloaded from second vessel can be used to cool the CO2 stream being loaded on to the first vessel or to provide coldness to the CO2 liquefaction unit that is connected to first vessel.

In an embodiment in which the vessel <NUM> is not configured for simultaneous loading/unloading, the coldness of the CO<NUM> stream can contribute to the liquefaction of the LPG at LPG production unit <NUM> via thermal linkage <NUM> and/or maintain the temperature of the LPG at the LPG storage facility <NUM> through thermal linkage <NUM>. Thermal linkages <NUM> and <NUM> can connect the LPG production unit <NUM> and/or the LPG storage facility <NUM> with one or more of line <NUM>, line <NUM>, line <NUM> and/or CO<NUM> storage facility <NUM>. While <FIG> shows thermal heat linkage <NUM> as being operatively connected to LPG storage unit <NUM>, in at least one embodiment, thermal linkage <NUM> can be operatively connected to the LPG production unit <NUM> and/or LPG line <NUM>. As with the thermal linkages <NUM> and <NUM> at Point B, the thermal linkages <NUM> and <NUM> can comprise one or more heat exchangers or thermal transfer loops that can contain transfer fluid having a low freezing point, for example. The transfer fluid can be circulated within the thermal transfer loop using a pump or other practical means. Thermal transfer between the LPG facilities (LPG production unit <NUM>, LPG production unit <NUM>) and the CO<NUM> facilities (supercritical CO<NUM> cycle <NUM>, CO<NUM> storage <NUM>) liquefaction unit <NUM> via the thermal transfer loop (thermal linkages <NUM> and <NUM>) can be accomplished in various ways known in the art, including via heat exchanger fins or coils along with a suitable heat exchanger fluid, for example high normal boiling point temperature hydrocarbons such as pentane, hexane, or water ethylene glycol mixtures. It should also be understood that other thermal linkages of the systems of the present application can be arranged in a similar fashion or by other practical means as would be understood by those skilled in the art.

As discussed above, once the vessel has loaded the LPG load at Point A (and CO<NUM> has been unloaded), it can transport it from Point A to Point B. Alternatively, the vessel can transport all or a portion of the LPG load to another land-based, on-shore, or off-shore unloading point. The vessel <NUM> is configured to meet and maintain the pressure and temperature requirements for LPG during transport as well as for liquefied CO<NUM> during transport. For instance, the vessel can be configured to transport CO<NUM> between its triple point temperature (approximately -<NUM>) and +<NUM>, and at pressures between approximately <NUM> bar and approximately <NUM> bar. In at least one embodiment, the vessel is configured to transport the CO<NUM> close to its triple point conditions, somewhere between the triple point temperature and -<NUM> and at a pressure between <NUM> and <NUM> bar. The vessel can have a dedicated refrigeration and liquefaction unit to condense the LPG boil-off along the way or can use the same boil-off liquefaction unit for CO2 and LPG.

As discussed above, the vessel <NUM> can have one or more storage containers (storage tanks) <NUM> for storing the CO2 and/or the liquid hydrocarbon (e.g., LPG). In one or more embodiments, the vessel <NUM> can have at least one dedicated storage container for the LPG (or other liquefied hydrocarbon stream) and at least one dedicated storage container for CO<NUM>. In one or more embodiments, the storage containers for LPG and CO<NUM> can be semi-pressurized and refrigerated. In at least one embodiment, a common storage container can be used to transport the LPG (or other liquefied hydrocarbon stream) and the CO2 in the respective directions of the transport scheme. In embodiments in which a common storage container is used, conditioning on the storage tank (e.g., depressurization, purging of the previously fluid, CO2 or LPG) must be performed when switching from one fluid to another.

It should be understood that at the various loading and unloading facilities, such as at Points A and B as shown in <FIG>, the vessel <NUM> is configured to selectively connect to the various loading and unloading facilities using one or more detachable connectors <NUM> (e.g., selectively connectable pipes or tubing) configured to provide a fluid connection for transferring or receiving the liquefied hydrocarbon and/or CO<NUM> streams to and from the vessel. In one or more embodiments, each connector <NUM> can comprise two parts. A first part of the connector <NUM> selectively attached to the pipe/tubing of the loading and unloading facilities. Likewise, a second part of the connector <NUM> can be selectively attached to the pipe/tubing of the storage tank of the vessel. The first part and the second part of the connector <NUM> can be mate together the form a sealed connection between the pipe/tubing of the storage tank of the vessel and the pipe/tubing of the loading or unloading facilities.

It should also be understood that while the above description generally refers to the vessel transporting LPG and CO<NUM> between "Point A" and "Point B," in certain embodiments the vessel <NUM> can transport the liquid hydrocarbon stream and/or the CO<NUM> to locations other than Point A and Point B, such as other land-based, on-shore, or off-shore locations. Transportation to the other locations can be in lieu of transportation to Point A and/or Point B or in addition to transportation to Point A and/or Point B.

<FIG> provide a high-level diagram of an embodiment of the CO<NUM> and liquid hydrocarbon transport scheme, including exemplary thermal linkages (including heat exchangers B2 and CX2) in the transport scheme in accordance with one or more embodiments. In particular, <FIG> displays a high-level scheme showcasing some of the integration options and levels of temperatures and pressures expected in the different flows.

In at least one embodiment, the same logic for co-transport of CO<NUM> with hydrocarbons as shown in <FIG> can be followed and can include the heat integration at both ends of the transport scheme. In one or more embodiments, the LPG as shown in <FIG> and <FIG> can be replaced by liquefied natural gas (LNG). In such an embodiment, CO<NUM> and LNG can be transported in the same vessel and can have heat integration at both terminals (i.e., Points A and B). A primary difference in such an embodiment is that LNG is transported at a temperature lower than CO<NUM>, so LNG coldness is used at the destination terminal (i.e., Point B) to liquefy the CO<NUM> and maintain the temperature of the CO<NUM> storage facility. On the LNG loading side (Point A), the CO<NUM> coldness is used to assist the liquefaction of the LNG. The CO<NUM> feeding the supercritical CO<NUM> cycle would remain the same in all cases.

In at least one embodiment, LPG can be replaced by other hydrocarbon-based substances (preferably between C1 to C7 hydrocarbons individually or as mixture) such as ethylene, dimethyl ether (DME), or any other hydrogen carrier with the optionality to transport back the CO<NUM>. In addition, in at least one embodiment LPG can be replaced by liquefied ammonia.

Accordingly, as described in the above description, the present systems and methods allow for heat transfer and energy recovery between the unloading and/or neighboring facility and the coldness of the transported goods (e.g., CO<NUM> and LPG). In addition, the present systems and methods allows for an effective re-liquefaction of the CO<NUM> boil-off and CO<NUM> purification while removing the non-condensable gases (e.g., nitrogen). Further, the present systems and methods allow for the reduction of the CO<NUM> transport costs by allowing the usage of the same vessel that is carrying hydrocarbons such as LPG or ammonia to transport the CO<NUM> on its way back to load additional hydrocarbons instead of returning empty, which saves considerable CO<NUM> transport costs. The present systems and methods also teach coldness integration with the unloading terminal and/or nearby facilities which reduces the overall energy intensity at the unloading terminal.

The present systems and methods also overcomes shortcomings in the field. In particular, there is a lack of efficient or proven ways to transport liquid hydrogen (i.e., liquid hydrocarbons) over long distances and other hydrogen carrier options such as ammonia or methylcyclohexane are expensive. Further, current technologies do not link the energy recovery of the coldness of LPG and CO<NUM> at both terminal (e.g., in the present scheme, Point A and Point B). Finally, the present systems and methods allows for heat/cold integration in different parts of the transport chain and purifies the CO<NUM> feed while it is being transported in the vessel, thereby saving overall energy consumption and reducing the CO2 transport costs. As such, the present systems can be a significant part of the overall Carbon Capture and Sequestration (CCS) chain.

It should be understood that although much of the foregoing description has been directed to systems and methods for efficiently transporting liquid hydrocarbons and CO<NUM>, the system and methods disclosed herein can be similarly deployed and/or implemented in scenarios, situations, and settings far beyond the referenced scenarios. It should be further understood that any such implementation and/or deployment is within the scope of the system and methods described herein.

It is to be further understood that like numerals in the figures represent like elements through the several figures, and that not all components and/or steps described and illustrated with reference to the figures are required for all embodiments or arrangements. Further, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. It will be further understood that the terms ""including," "comprising," or "having," "containing," "involving," and variations thereof herein, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It should be noted that use of ordinal terms such as "first," "second," "third," etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

Claim 1:
A loading and unloading station for sequentially unloading CO<NUM> from at least one storage tank in a vessel and for loading LPG into a storage tank of the same vessel, comprising:
an LPG production unit (<NUM>);
an LPG storage unit (<NUM>), the storage unit (<NUM>) being in fluid communication with the LPG production unit (<NUM>);
a first connector (<NUM>) for fluid connection to the LPG storage unit (<NUM>) for loading the LPG into the storage tank of the vessel;
a second connector (<NUM>) for unloading the CO<NUM> into a CO<NUM> storage unit (<NUM>);
a CO<NUM> compression unit (<NUM>) that compresses the CO<NUM> above a predetermined pressure;
a supercritical CO<NUM> unit (<NUM>) that receives CO<NUM> from the compression unit (<NUM>), wherein the supercritical CO2 unit (<NUM>) is characterised by
an internal heat exchanger (<NUM>), an external heat exchanger (<NUM>), and a CO2 turbine (<NUM>), wherein the internal and external heat exchangers (<NUM>, <NUM>) are configured to heat a high pressure, cold CO2 stream to form a high pressure, high temperature CO2 stream, and wherein the CO2 turbine (<NUM>) is configured to expand the high pressure, high temperature CO2 stream to generate power; and
thermal linkages (<NUM>, <NUM>) that put the high pressure, cold CO<NUM> stream from the supercritical CO<NUM> unit (<NUM>) and the CO<NUM> compression unit (<NUM>) in contact with the LPG production unit (<NUM>) and the LPG storage unit (<NUM>), including:
(A) a first thermal linkage (<NUM>) that is configured to transfer coldness from the cold CO<NUM> stream to facilitate liquefaction of the LPG in the LPG production unit (<NUM>) and (B) a second thermal linkage (<NUM>) that is configured to maintain temperature of the LPG storage unit (<NUM>).