An installation for transport and storage of hydrogen and its mixtures as a response to mobility and urban energy independence.
The subject of the research in this paper is the analysis of transport and storage systems, especially for hydrogen and hydrogen mixtures in their compressed or liquid state, mainly from the producers (e.g. photovoltaic farms) to the final users, which are usually gas/hydrogen retail or wholesale distribution stations, power plants e.g. The end users are usually retail or wholesale gas/hydrogen distribution stations, power plants e.g. hydrogen cells switched on during the peak of power consumption, plants using gas-hydrogen permanently as an alternative, cheap and ecological source of energy for obtaining electricity and heat, stations reducing gas-hydrogen pressure and further distribution. What is particularly important, it is possible to use the described dedicated solution in individual residential houses, or stations for the production of liquid hydrogen.
The hydrogen transport and storage system according to the first variant of its execution shown in Fig. 1 consists of a horizontally positioned tubular element 1 placed above the ground, one end of which is connected to a hydrogen supplier A, which is an aboveground storage tank (tank-type), and the other end of this tubular element 1 is connected to a pump 2 that injects hydrogen at a pressure of 700/bar into a curved tubular element 3 connected to a controllable non-return valve 4 (of the open-close type), connected to a first underground vertical tubular element 5 with a height of H1 = 10 m, which, through a horizontal tubular element 6 of length L
= 100 m, is connected to a second vertical tubular element 7 with a height of H2 = 10 m so that both vertical tubular elements 5 and 7 and the horizontal tubular element 6 forms a tubular “U-profile”. The upper end of the vertical tubular element 7 is connected to a controllable one-way valve 8 (of the open-close type) protruding above the ground surface, connected to an arched tubular element 9, by which hydrogen is supplied to customer B, a retail hydrogen distribution station for refuelling hydrogen vehicles, for example. In addition, a 230V mains-powered heating and cooling device 10 is adjacent to the outer surface of the tubular elements 5, 6, 7 and 9, which maintains the hydrogen temperature throughout the network at 20° C. Furthermore, in this variation of the design, each of the tubular elements 5, 6 and 7 had a diameter of ϕ = 5 cm.
The installation for the transport and storage of hydrogen together with natural gas according to the second variant of its design shown in Fig. 2 is similar in construction to the installation described in the first example (Fig. 1), the difference being that, in the latter design, the lower ends of the vertically and parallel positioned tubular elements 5 and 7 are connected to each other by an inclined tubular element 6 so that an acute angle α = 70° is formed between the tubular element 5 and the inclined tubular element 6, the height of the vertical tubular element 5 being H1 = 300 m, the height of the vertical tubular element 7 being H2 = 100 m and the length of the inclined tubular element 6 being L=3000 m. Besides, in this second variation of the network design, hydrogen with natural gas by pump 2 was injected into the curved tubular element 3 at a pressure of 1000 bar, and the tubular element 9 was equipped with an additional pump 11 for pumping hydrogen with natural gas, mounted between a controllable one-way valve 8, and the consumer B of this hydrogen was the municipal/local gas system. In turn, tubular elements 1, 3, 5, 6, 7 and 9 are made of austenitic steel, with both vertical tubular elements 5 and 7 having a diameter of ϕ = 18 cm, while the connecting obliquely located tubular element 6 has a diameter of ϕ = 15 cm.
The compressed hydrogen transport and storage system according to the third variant of its design shown in Fig. 3 has a similar construction to the system described in the first example, the difference between these variations is that in this third variation the compressed hydrogen supplied from two independent suppliers A and A’ via pipe elements 1, pumps 2, curved pipe elements 3, controllable one-way valves 4 and vertical tubular elements 5 and 5′ were injected into a common horizontal tubular element 6 connected to these vertical tubular elements 5 and 5′ also connected to two vertical tubular elements 7 and 7′ from where, through valves 8 and curved tubular elements 9, it was delivered to two independent consumers B and B’. In this example of implementation, consumer B’ was a (not shown) Hampson-Linde condenser, housed in what acted as a Dewar vessel, a “U-profile” element located below ground and connected to a compressed hydrogen network. The result is liquefied hydrogen used, for example, in reciprocating engines, as fuel for refuelling aircraft just before they take off, as fuel for refuelling all types of launchers and in other technological processes requiring liquefied hydrogen.
In addition, in this design variation, the height of the vertical tubular element 5 is H1 = 500 m, the height of the vertical tubular element 5′ is H1′ = 300 m, the height of the tubular element 7 and 7′ is H2 = 500 m, and the tubular element 6 has a length of L=10000 m, while the diameter of the tubular elements 5, 5′, 6, 7 and 7′ is ϕ = 30 cm. In the variation of the design of this network, a heating and cooling device 10 is attached to the outer surfaces of the tubular elements 5, 5′, 6, 7, 7′ and 9, and hydrogen at a temperature of 20°C was injected by pumps 2 at a pressure of 800 bar.
The compressed hydrogen transportation and storage system according to the fourth variant of its design shown in Fig. 4 is similar in construction to the system described in the first example, the difference being that in this variant of the design, a device 12 for equalizing the hydrogen pressure in the system is placed between the pump 2 and the controlled non-return valve 4. This device is a tubular element 3, one end of which is connected to pump 2 and the other branched end, via controllable one-way valves 4′, is connected to two equalization tanks 13 of low pressure of not less than 100 bar placed underneath each other, whereby the expansion tanks 13 via pipe elements 3′ with one-way valves 4′ are connected to an expansion tank 14 of medium pressure, of not less than 500 bar, located below the ground surface, which in turn is connected via pipe element 3′ and controllable one-way valve 4 to the vertical pipe element 5 of the “U-profile” element of the installation.
The installation of an additional device 12 for equalizing the pressure in this variant of the design of the system according to the invention has the effect of maintaining a constant gas pressure level in the pipeline at 700 bar in the event of this pressure mixing in the system as a result of the intake of hydrogen by the consumer or consumers B, B’.
In another implementation example not shown in the figure, an installation according to the invention similar to the installation described in example 1 was used for the transport and storage of ammonia.
In all variants of the design of the installation for transporting and storing hydrogen and its mixtures, tubular elements 5, 5′, 6, 7 and 7′ are embedded in previously drilled vertical and horizontal (corridor) holes in the ground, while the installation according to the invention can also be placed in existing mining boreholes, which makes it possible to revitalise them. Furthermore, the tubular elements 5, 5′, 6, 7 and 7′ of the system according to the invention are made of materials designed for contact with specific gases, among other things, resistant to hydrogen embrittlement. These are multilayer composite tubes made of different materials, preventing even single hydrogen atoms from diffusing. In turn, the temperature in the system was maintained by commonly used heating and cooling units or heat exchanger units. The heating/cooling equipment used in the solution according to the invention is a typical device used to heat/and/or cool gas, such as a GHP Chiller pump or other device using water/glycol circulation, which stabilises the gas temperature according to its type and pressure, whereby the device is selected individually according to the type of installation and compressor/pump used.
In other examples of implementation not shown in the figure, the vertical tubular elements and the horizontal tubular element were located in different configurations (at different angles) following the principle of communicating vessels (U-tube).
It is clear that the horizontal section of the installation according to the invention may have several independent connections to suppliers and customers, and that the diameters, heights and lengths of its individual tubular elements are not limited to those shown in the manufacturing examples and may depend on the distance between supplier and customer, technical possibilities, ground layers, etc., whereby the minimum depth of placement of the tubular U-profile must be greater than the permafrost boundary and the weight of the top soil layer above the U-profile must balance at least the planned gas pressure in its tubular elements, whereby in the installation according to the invention the transported and stored gas is compressed to a pressure in the range from 100 – 1000 bar.
Besides, the interconnection of several installations according to the invention makes it possible to create a hydrogen network supplying hydrogen and hydrogen mixtures from one supplier to several even very distant customers, including another city or region, as well as supplying this gas from several suppliers to one customer, as schematically shown in Fig. 5.
In a further manufacturing example shown in fig.6, the installation according to the invention had a construction similar to that of the installation shown in the first manufacturing example (fig.1 ), the difference between the two is that in this example the U-profile is replaced by a U-tube element 5” curved in its lower part 15, one upper end of which through a one-way valve 4 is connected to the tubular element 3, while the other upper end of the tubular element 5” through a one-way valve 8 is connected to the tubular element 9, while the heating and cooling device 10 is adjacent to the outer surfaces of the tubular elements 5” and 9, the U-tube element 5” has a diameter of Ø = 100 cm and length L1 = 300 cm and is placed in a hollow in the ground 3.5 m deep and 300 cm in diameter, which was backfilled with soil after the insertion of the tubular element 5” and the heating and cooling device 10.
Prof. Piotr Zawada, PhD. – Head of the Department of Managerial Economics at the Faculty of Socio-Economic of UKSW.
Jerzy Jurasz – author of inventions and innovative and technological solutions, the creator of 3 patent applications in the field of health water production, high-pressure fluid processing, and hydrogen transport and storage.