R.J.M. Hermkens, H. Colmer, H.A. Ophoff
Papers # 2018 Las-Vegas
To investigate the suitability of PE pipes for the transport of hydrogen on a specific industrial site, three topics were investigated. These topics are: the chemical resistance of PE to hydrogen, the permeation rate of hydrogen through PE and the electrofusion of PE pipes exposed to hydrogen. It can be concluded that the tested PE100-RC pipes on the premises of Groningen Seaport are suitable for the transport of hydrogen at pressures of up to 2 bar. However, during design and maintenance, the specific characteristics of hydrogen that distinguish it from methane need to be taken into account.
At Groningen Seaports, hydrogen gas is produced as a by-product on a local chemical site. To encourage reuse of this kind of energy-rich waste, the hydrogen is used as a fuel for scheduled buses in the northern part of the Netherlands (Groningen).
A special pipeline is installed to transport the hydrogen from the production facility to the filling station where the buses are fueled with the hydrogen. It is important that the long-term safety and security of this pipeline can be guaranteed. Moreover, the construction and maintenance process must be carried out cost-effectively. Polyethylene with raised crack resistance (PE100-RC) was selected as a potential piping material. As there is little experience with the combination of this PE piping material and hydrogen gas, a study was carried out before construction work started. This study considered safety and material aspects, as well as maintenance issues for this particular pipeline at this specific location. Factors such as installation modes of the pipe and various possible maintenance activities during the operational phase were considered. A number of important material parameters, such as the permeation rate and the fusibility after prolonged exposure to hydrogen gas, were investigated for the selected PE100-RC material. The results of the study and additional insights into the construction of this pipeline are presented.
In the near future, the available volume of hydrogen gas is set to increase. This is especially so if the surplus renewable energy generated by photovoltaic cells or wind turbines is used to produce hydrogen gas. This could result in additional opportunities beyond the new applications mentioned above. The existing natural gas network offers new and economically interesting opportunities to store and transport this excess renewable energy in the form of hydrogen gas. However, a possible drawback is the volume of hydrogen gas emitted from the oldest natural gas networks as a result of permeation, since this may prove to be higher than for modern PE materials. As such, permeation tests on these old (first-generation) PE pipes will also be investigated in the near future.