A system for on-demand hydrogen generation from a carrier liquid and disposal of solid byproducts.

Abstract

The present invention provides an apparatus for controlled generation of gas from a first fluid reagent and a second fluid reagent, the first fluid reagent and the second fluid reagent generating the gas and byproducts upon mixing, the apparatus comprising: a reactor cylinder (10); inlets (12a, 12b) configured to supply the first reagent (HC) and the second reagent (PS) to the reactor cylinder; a gas discharge circuit (18) connected to the reactor cylinder; a piston (14) inside the reactor cylinder, the piston being actuated from a first end of the reactor cylinder to move axially within the cylinder to compress any byproducts onto a second end of the cylinder and discharge any gas through the gas discharge circuit (18), wherein the gas discharge circuit is connected to the cylinder near the second end of the cylinder; and a shut-off device (22) at the second end of the cylinder, the shut-off device having a closed position sealing the second end of the cylinder and an open position completely releasing the second end of the cylinder so that any byproducts in the cylinder can be removed by the piston (14).

Description

Technical Field

[0001] This invention relates to hydrogen-supported compounds, and more specifically to hydrogen generated from liquid hydrogen supports. The generation system can be more generally applied to generate any gas by mixing fluid reagents, leaving solid byproducts. Background Technology

[0002] Hydrogen support compounds can transport large quantities of hydrogen in solid or liquid form, facilitating hydrogen transport. Such hydrogen supports can be from the silylated derivative family, and more specifically, the hydrogen-polysiloxane family, which have the general formula (HRSiO). n To extract hydrogen, a hydrogen support compound is mixed with a so-called proton source (usually water) in the presence of a catalyst, see, for example, patent applications WO02010094785 and WO2011098614. After hydrogen production, byproducts remain that need to be removed from the system and eventually recycled.

[0003] The challenge lies in extracting hydrogen from such components on demand while removing byproducts without hydrogen leakage, especially when the byproducts are solid. Patent application WO2012151582 discloses a hydrogen generation system based on a solid hydrogen carrier capable of removing solid byproducts. Summary of the Invention

[0004] The invention provides an apparatus for controlled generation of gas from a first fluid reagent and a second fluid reagent, the first fluid reagent and the second fluid reagent generating the gas and byproducts upon mixing, the apparatus comprising: a reactor barrel; an inlet configured to supply the first reagent and the second reagent to the reactor barrel; a gas discharge circuit connected to the reactor barrel; a piston inside the reactor barrel, the piston being actuated from a first end of the reactor barrel to move axially within the barrel to compress any byproducts onto a second end of the barrel and discharge any gas through the gas discharge circuit, wherein the gas discharge circuit is connected to the barrel near the second end of the barrel; and a shut-off device at the second end of the barrel, the shut-off device having a shut-off position sealing the second end of the barrel and an open position completely releasing the second end of the barrel so that any byproducts in the barrel can be removed by the piston.

[0005] The gas discharge circuit may include: a high-pressure gas circuit connected to the cylinder via a check valve; and a low-pressure gas circuit connected to the cylinder via an operating valve.

[0006] The piston may include a peripheral sealing ring offset from the piston end, such that when the piston is in a position where it compresses the byproduct onto the second end of the cylinder, the portion of the piston wall between the sealing ring and the piston end faces the inlet port of the gas discharge circuit.

[0007] A method for controlling the generation of a gas is also provided, the method comprising the steps of: generating the gas and a byproduct by mixing a first fluid reagent and a second fluid reagent in a reactor cylinder; collecting the generated gas by a gas discharge circuit connected to the cylinder; compressing the byproduct to an end of the cylinder by a movable piston while discharging the gas remaining in the cylinder through the gas discharge circuit, wherein the gas discharge circuit is radially connected to the cylinder near the end of the cylinder; fully opening the end of the cylinder; and discharging the byproduct through the end of the cylinder by the piston.

[0008] The method may further include the following additional steps: collecting the generated gas through a check valve; and releasing the remaining gas in the cylinder by means of a low-pressure gas circuit connected to the cylinder near the end of the cylinder after the byproduct is compressed and before the end of the cylinder is opened.

[0009] The first reagent can be a liquid hydrogen carrier, and the second reagent is a liquid proton source, thereby producing a hydrogen gas.

[0010] The hydrogen carrier can be a liquid silylated derivative.

[0011] The hydrogen carrier can be a liquid dihydropolysiloxane, thereby producing a solid byproduct that is essentially composed of silicates. Attached Figure Description

[0012] Other advantages and features of the invention will become more apparent from the following description of specific embodiments of the invention, which are provided for illustrative purposes only and are illustrated in the accompanying drawings, in which:

[0013] ■ Figures 1A to 1F An embodiment of an apparatus for generating hydrogen from a liquid hydrogen carrier while leaving solid byproducts is shown in different stages of the generation cycle. Detailed Implementation Plan

[0014] Figure 1A This is a schematic diagram of an embodiment of an apparatus for on-demand hydrogen production from the reaction of two reagents, both of which can be provided in liquid form. The apparatus has a byproduct removal mechanism capable of handling solid byproducts, wherein hydrogen leakage is negligible.

[0015] The apparatus includes a reactor cylinder 10 having corresponding valve-operated inlets 12a and 12b for two reagents, namely a hydrogen carrier HC and a proton source PS. The inlets are radially arranged (e.g., centrally located) within the cylinder wall.

[0016] The piston 14, arranged inside the cylinder, is configured to move axially between the two ends of the cylinder. In the accompanying drawings, the piston is actuated from the right end of the cylinder by a conventional device not shown.

[0017] Gas venting circuit 16 is radially connected to the wall of the cylinder near its left end. The venting circuit may include a high-pressure circuit having a hydrogen storage tank hpH2 connected to the cylinder via a check valve 18. The venting circuit also preferably includes a low-pressure circuit having a hydrogen storage tank 1pH2 connected to the cylinder via an operating valve 20.

[0018] The terms "high pressure" and "low pressure" are intended to be relative, not quantitative. The actual pressure in a high-pressure tank can vary significantly during operation and depends on the application, but it is generally greater than the pressure in a low-pressure tank. The pressure in a low-pressure tank can actually be near atmospheric pressure.

[0019] The left end of the cylinder 10 is closed by a removable cover, such as a piston 22, which is configured such that when the cylinder is moved to the left, the corresponding end of the cylinder remains open without obstruction.

[0020] Figure 1A This corresponds to the initial stage of the device's operating cycle, in which the cylinder is empty and ready to receive reagents HC and PS. Control valves 12a, 12b, and 20 are all closed.

[0021] Figure 1B Corresponding to the second stage, the reaction stage, valves 12a and 12b open, allowing reagents HC and PS to enter the cartridge. In this cartridge, the reagents mix and react to produce hydrogen (H2). As the hydrogen is produced, it is discharged through check valve 18 into the high-pressure circuit, where it can either fill tank hpH2 or be consumed directly. The reaction produces a solid byproduct, which initially fills cartridge 10.

[0022] exist Figure 1C In this configuration, cylinder 10 is filled with the byproduct, shown here as a pile of powder. In practice, the byproduct can be in the form of a porous and fragile cake. The reagent feed is shut off by valves 12a and 12b. The actual saturation threshold can be defined as the maximum amount of byproduct that can be efficiently processed in subsequent steps, which in practice is less than the volume of the cylinder.

[0023] exist Figure 1D In the process, piston 14 moves inward toward the opposite end of cylinder 10. As piston 14 moves, it compresses the byproducts onto closing piston 22 and discharges the remaining hydrogen in the cylinder into storage tank hpH2 through check valve 18.

[0024] exist Figure 1EIn this process, the byproducts have been compressed into agglomerates that essentially occupy the entire volume between pistons 14 and 22 in the cylinder. Ideally, the pressure applied by piston 14 is sufficient to collapse all the pores in the byproduct agglomerates, thus expelling all the gaseous hydrogen contained in the byproducts. In practice, such pressure may be unattainable, and the piston actuator is configured to apply a pressure below the component's burst limit.

[0025] At this location, under the pressure of the high-pressure storage tank hpH2, the cylinder still contains hydrogen in the residual volume inside and around the byproduct agglomerates. This residual volume is negligible. At this stage, the cylinder can be opened to vent the byproduct agglomerates, thereby releasing a certain amount of hydrogen into the outside air. This hydrogen can be harmlessly discharged through appropriate ventilation.

[0026] Preferably, by using a low-pressure gas circuit including valve 20 and low-pressure hydrogen tank 1pH2, the amount of residual hydrogen released into the outside air is significantly reduced. Therefore, in Figure 1E During this phase, valve 20 opens, thereby releasing the high-pressure residual hydrogen in the cylinder into the low-pressure tank lpH2. Check valve 18 prevents the hydrogen in the high-pressure tank hpH2 from returning to the cylinder when the pressure in the cylinder drops and equalizes with the pressure in the low-pressure tank lpH2.

[0027] For the proper operation of the hydrogen emission process, the gas emission loop should remain connected to the portion of the can containing residual hydrogen throughout the by-product compaction process. Preferably, the inlet port of the emission loop should not be in direct contact with by-product agglomerates, as some by-products may eventually pass through and clog the port. As shown in the figure, in Figure 1E In this configuration, the discharge loop port can be positioned facing the wall portion of the piston rather than the byproduct agglomerates. To allow the release of residual hydrogen, any sealing rings of the piston are offset from the end of the piston beyond the discharge loop port, as shown for a single sealing ring 24, allowing residual hydrogen to flow into the discharge loop through the gap between the piston and the cylinder.

[0028] exist Figure 1F In the process, valve 20 closes when the cylinder end is opened by shifting the closing piston 22 to the left. By further moving the piston 14 to the left to a position flush with the cylinder end, the byproduct agglomerates are discharged from the cylinder.

[0029] To return to Figure 1AThe configuration is such that a new hydrogen production cycle begins, piston 22 moves back to close the cylinder end, and piston 14 moves back to the opposite end of the cylinder. Thus, moving piston 14 creates a vacuum in the cylinder, preventing the generated hydrogen from mixing with air in each cycle. Alternatively, valve 20 can be opened as piston 14 moves back, thereby filling the cylinder with low-pressure hydrogen. If the pressure in low-pressure tank 1pH2 is higher than atmospheric pressure, this pressure may even push the piston. Yet another alternative is to push piston 14 back with hydrogen contained in high-pressure tank hpH2 by operating a valve (not shown) that bypasses check valve 18.

[0030] If the hydrogen is not consumed during operation, each cycle increases the hydrogen pressure in tanks hpH2 and lpH2. The pressure in tank hpH2, originating from the primary hydrogen production process, builds up much faster than the pressure in tank lpH2, which in principle originates from the residual hydrogen left after the compression of byproducts. In practice, tank hpH2 can reach pressures of tens of bar, while the pressure in tank lpH2 can be around 1 bar. Therefore, the high-pressure tank hpH2 is suitable for storing hydrogen, while the low-pressure tank lpH2 can be used for immediate low-pressure applications, such as supplying hydrogen fuel cells.

[0031] As previously mentioned, the hydrogen carrier reagent HC can be from the hydrogen-methyl-polysiloxane family, with the general formula (HRSiO). n It can be provided in liquid form. Among other possibilities, the proton source reagent PS might simply be water. However, the resulting byproducts are difficult to recycle.

[0032] The preferred hydrogen support will be a dihydropolysiloxane family, having the general formula (H₂SiO). n Because their byproducts are essentially the corresponding silicates, which can be readily recycled back into the hydrogen support. In other possibilities, this compound also reacts with water as a proton source.

[0033] Dihydropolysiloxanes exist only in solid form and are difficult to produce industrially. However, patent application EP18305549 discloses a method for the industrial production of dihydropolysiloxanes in liquid form, which makes them particularly suitable for the system of the present invention.

[0034] The system disclosed herein is applicable to generating gas from any fluid reagent, leaving behind solid byproducts. Although the device is specifically designed to handle solid byproducts, it can also be used to handle liquid byproducts in a very similar manner. For liquid byproducts, in stage 1E, piston 14 can be actuated in a controlled manner such that it stops when the liquid byproduct reaches the port of the gas discharge circuit located at the highest point of the cylinder. In this case, the amount of residual hydrogen will be close to zero, especially if the liquid byproduct is a fluid sufficient to fill all the volume of the cylinder up to the gas discharge port.

Claims

1. An apparatus for controlled generation of a gas from a first fluid reagent and a second fluid reagent, wherein the first fluid reagent and the second fluid reagent generate the gas and byproducts upon mixing, the apparatus comprising: • Reactor cylinder (10); • Inlet (12a, 12b), the inlet being configured to supply the first fluid reagent and the second fluid reagent to the reactor shell; • Gas exhaust circuit (18), which is connected to the reactor shell; The device is characterized in that it comprises: • Piston (14), inside the reactor tube, actuated from a first end of the reactor tube to move axially within the reactor tube to compress any byproducts to a second end of the reactor tube and discharge any gas through the gas discharge circuit (18), wherein the gas discharge circuit is connected to the reactor tube near the second end of the reactor tube; and • Shut-off device (22), located at the second end of the reactor tube, having a closed position that seals the second end of the reactor tube and an open position that completely releases the second end of the reactor tube so that any byproducts in the reactor tube can be removed by the piston (14).

2. The apparatus according to claim 1, wherein the gas emission circuit comprises: • High-pressure gas circuit, which is connected to the reactor cylinder via a check valve; and • Low-pressure gas circuit, which is connected to the reactor cylinder via an operating valve (20).

3. The apparatus of claim 1, wherein the piston includes a peripheral sealing ring (24) offset from one end of the piston, such that when the piston is in a position that compresses the byproduct onto the second end of the reactor tube, the portion of the piston wall between the sealing ring and the end of the piston faces the inlet port of the gas discharge circuit.

4. A method for controlling the generation of gas, the method comprising the following steps: • The gas and byproducts are generated by mixing a first fluid reagent and a second fluid reagent in the reactor tube (10); • The generated gas is collected through a gas exhaust loop (18) connected to the reactor cylinder; The method is characterized by comprising the following steps: • The byproduct is compressed to the end of the reactor tube by a movable piston (14), while the gas remaining in the reactor tube is discharged through the gas discharge circuit, wherein the gas discharge circuit is radially connected to the reactor tube near the end of the reactor tube. • Fully open the end of the reactor tube; and • The byproduct is fed out through the end of the reactor tube using the piston.

5. The method according to claim 4, further comprising the following additional steps: • The generated gas is collected via a check valve; and • After the byproducts are compressed and before the end of the reactor tube is opened, the gas remaining in the reactor tube is discharged through a low-pressure gas circuit connected to the reactor tube near the end of the reactor tube.

6. The method of claim 4, wherein the first fluid reagent is a liquid hydrogen carrier and the second fluid reagent is a liquid proton source, and the gas produced therefrom is hydrogen.

7. The method according to claim 6, wherein the liquid hydrogen carrier is a liquid silylated derivative.

8. The method according to claim 6, wherein the liquid hydrogen carrier is a liquid dihydropolysiloxane, thereby producing a solid byproduct composed of silicates.

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