1 Important Developments in the History of Ionic Liquids …
11
technique was granted in 2006 [62]. At the same time, a patent was obtained by
another company
13 [63] on liquids for compressing a gaseous medium. The claims
comprise liquids with a vapor pressure <10
−3 mbar, preferably ionic liquids. Another
patent for a modified ionic compressor followed in 2008 [64]. The first commercial
installation started in July 2005 in Austria.
14 The unit supported a fuel station for
natural gas and operated at 25 MPa with a capacity of 500 m
3 natural gas per hour
[53].
The ionic compressor is now part of some hydrogen fueling stations. The flagship
model that qualifies for the fueling protocol SAE J2601-A70 [65] is a five-stage ionic
compressor with a stage compression ratio of 1:2.8, an input pressure from 0.5 to
20 MPa, a maximum output pressure of 100 MPa, a stroke frequency of 5.8 Hz, a
maximum delivery rate of about 33.6 kg hydrogen per h (as single line, double line
is optional), and a specific energy consumption of 2.7 kWh per kg hydrogen. Noise
emission is lower than 75 dB at 5 m. The target fueling pressure is 70 MPa at 288 K
[66]. Compared with conventional piston pumps, energy consumption is reduced
by about 20%, and the equipment can run about 500 days without maintenance—a
factor of 10 longer. The costs for maintenance were also reduced by about 50% [53,
61]. In 2014, the compressor
15 entered production [61].
In a recently released brochure entitled The Driving Force, some reference projects
on hydrogen fuels describe the entire supply chain from production to the final
customer [67]. Ionic compressors supply hydrogen to a bus fleet in the towns of
Aberdeen, Scotland, and Hamburg, Germany, at the power-to-gas installation at the
Energiepark in Mainz, Germany, at the first hydrogen fueling station in the USA
(opened in October 2014) in Sacramento, California, and at Japan’s first commercial
hydrogen fueling station in Iwatami.
In a presentation from November 18, 2014, which was later displayed on the
web, Beckman outlined a corporate strategy in the hydrogen fueling business [68].
As a result of an infrastructure project with the government of California, ionic
compressors are working at nine different hydrogen fueling stations. Beckman gives
an estimate of 87 stations in California by the year 2020. An initiative for hydrogen mobility in Germany forecasts the construction of about 400 hydrogen fueling
stations in the country by 2023.
Notably, the corporate documents released on an ionic compressor do not explicitly specify an ionic liquid. That information is proprietary, but it can be assumed
that the best substance to be employed matches the above-mentioned criteria for an
operating fluid. It is also likely that the company uses additives that improve the
performance.
The Ph.D. thesis by Nasrin Arjomand Kermani completed at the Technical University of Denmark (DTU) and published in 2017 gives an indication of potential ionic
liquid candidates [69]. In her work on the design of an ionic compressor, Arjomand
13 Proionic GmbH.
14 Wien Energie GmbH.
15 Model IC90 v 1.3, Linde GmbH.
11
technique was granted in 2006 [62]. At the same time, a patent was obtained by
another company
13 [63] on liquids for compressing a gaseous medium. The claims
comprise liquids with a vapor pressure <10
−3 mbar, preferably ionic liquids. Another
patent for a modified ionic compressor followed in 2008 [64]. The first commercial
installation started in July 2005 in Austria.
14 The unit supported a fuel station for
natural gas and operated at 25 MPa with a capacity of 500 m
3 natural gas per hour
[53].
The ionic compressor is now part of some hydrogen fueling stations. The flagship
model that qualifies for the fueling protocol SAE J2601-A70 [65] is a five-stage ionic
compressor with a stage compression ratio of 1:2.8, an input pressure from 0.5 to
20 MPa, a maximum output pressure of 100 MPa, a stroke frequency of 5.8 Hz, a
maximum delivery rate of about 33.6 kg hydrogen per h (as single line, double line
is optional), and a specific energy consumption of 2.7 kWh per kg hydrogen. Noise
emission is lower than 75 dB at 5 m. The target fueling pressure is 70 MPa at 288 K
[66]. Compared with conventional piston pumps, energy consumption is reduced
by about 20%, and the equipment can run about 500 days without maintenance—a
factor of 10 longer. The costs for maintenance were also reduced by about 50% [53,
61]. In 2014, the compressor
15 entered production [61].
In a recently released brochure entitled The Driving Force, some reference projects
on hydrogen fuels describe the entire supply chain from production to the final
customer [67]. Ionic compressors supply hydrogen to a bus fleet in the towns of
Aberdeen, Scotland, and Hamburg, Germany, at the power-to-gas installation at the
Energiepark in Mainz, Germany, at the first hydrogen fueling station in the USA
(opened in October 2014) in Sacramento, California, and at Japan’s first commercial
hydrogen fueling station in Iwatami.
In a presentation from November 18, 2014, which was later displayed on the
web, Beckman outlined a corporate strategy in the hydrogen fueling business [68].
As a result of an infrastructure project with the government of California, ionic
compressors are working at nine different hydrogen fueling stations. Beckman gives
an estimate of 87 stations in California by the year 2020. An initiative for hydrogen mobility in Germany forecasts the construction of about 400 hydrogen fueling
stations in the country by 2023.
Notably, the corporate documents released on an ionic compressor do not explicitly specify an ionic liquid. That information is proprietary, but it can be assumed
that the best substance to be employed matches the above-mentioned criteria for an
operating fluid. It is also likely that the company uses additives that improve the
performance.
The Ph.D. thesis by Nasrin Arjomand Kermani completed at the Technical University of Denmark (DTU) and published in 2017 gives an indication of potential ionic
liquid candidates [69]. In her work on the design of an ionic compressor, Arjomand
13 Proionic GmbH.
14 Wien Energie GmbH.
15 Model IC90 v 1.3, Linde GmbH.