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On August 8, 2018, Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) gave a public demonstration of its newly developed ammonia-to-hydrogen fuelling technology. What are the ramifications of this technology, you may well ask.
As the world looks for renewable and non-carbon-content fuels, hydrogen is by far the most likely candidate to supplement mains-charged, short-range electric vehicles. Already, Toyota and Hyundai have many years of hydrogen-fuel experimentation behind them and both Japan and South Korea are committed to a hydrogen-fuel future.
Recent announcements from the Ministry of Trade, Industry, and Energy (MTIE) in Seoul could push South Korea to the front of the fuel cell vehicle (FCV) pack.
According to an April 25, 2018, MTIE press release: “Vice Minister Lee Inho signed a memorandum of understanding with leaders from hydrogen-related industries to establish special purpose companies (SPCs) that will embark on an infrastructure development project for hydrogen fueling stations in Korea.”
Hyundai Motor Company President Chung Jin-haeng was among the attendees at the signing ceremony.
A May 2, 2018, Hydrogen Fuel News article reported:“The (South Korean) Government expects to see some 15,000 fuel cell vehicles on the road by 2022.
“These vehicles will be supported by 310 hydrogen stations that will all be open to the public by that time.”
On June 25, 2018, according to BusinessKorea, the South Korean Government and private-sector companies including Hyundai, Hyosung Heavy Industries and SK Gas will invest A$240 million this year and A$500 million next year. By 2022, A$3.4 billion will be invested in hydrogen car production facilities, hydrogen bus production, hydrogen storage containers for buses and stack plant expansion.
Where ammonia fits in
Hydrogen (H2) produces only water when combined with oxygen (O2) in a fuel cell, thus eliminating the NOx, HC and CO2 emissions that come from internal combustion engines.
The problems with hydrogen as a substitute for today’s liquid hydrocarbon fuels are its volatility and low density. Moving and storing gaseous hydrogen is a difficult and space consuming process.
Scientists and engineers agree that transporting and storing hydrogen is best done with the gas in a liquid or solid form and investigations include liquifying it or storing it in a recoverable compound. It’s even suggested that tiny hydrogen atoms could be stored inside solid structures.
Liquifying hydrogen for transport fuel purposes is unlikely ever to be viable, because enormous pressure vessels are required to liquify it and store it at temperatures around -253C.
The most likely ‘vehicle’ for hydrogen transport and storage is in the form of ammonia (NH3). Ammonia is a gas that can itself be used as a fuel, but currently needs very high combustion temperature conditions and can still produce NOx emissions. A much cleaner, more futuristic approach is to use ammonia as
the source of hydrogen as a fuel.
The idea is to produce ammonia cleanly, move it to where it’s needed and then convert the NH3 to N2 and H2. Transporting ammonia globally is easy with current technology.
The tricky bit is at the end of the transport process: converting the ammonia into hydrogen and nitrogen and that’s where the new CSIRO process comes into the picture.
Ammonia vapour from a storage tank is delivered to the conversion module, where one set of tubes cracks the ammonia into hydrogen and nitrogen in a reaction aided by a ruthenium catalyst. A second set of tubes with vanadium membranes performs the separation of hydrogen from nitrogen.
Fuel cells can be ‘poisoned’ by contaminants and, in the case of hydrogen sourced from ammonia, there’s an almost unbelievable purity requirement. The International Standards Organisation Standard 14687-2 specifies hydrogen fuel quality for polymer electrolyte/proton exchange membrane (PEM) fuel cells in mobile
Under this Standard any residual ammonia is restricted to an allowable limit of just 0.1 parts per million!
The August demonstration was a moment of truth for the CSIRO technology and the trail was a success, with the Toyota Mirai and Hyundai Nexo performing publicly on the CSIRO-derived hydrogen fuel.
The CSIRO project was aided by the South Korean Government, which has a keen interest in developing commercial-scale hydrogen fuel distribution in that country.Australian-produced ammonia could be the feedstock for that initiative.
Check out the ABC report:
Where to from here
The principal aim of the hydrogen fuel cell
is to provide an alternative propulsion unit, while eliminating traditional vehicle engine emissions. However, there’s little point if the exercise
of producing ammonia as a hydrogen ‘carrier’ causes emissions.
Ammonia is used extensively around the world for various purposes, including fertilisers.Annual global production is in excess of 800,000 tonnes.
Ammonia’s chief attraction is its ease of liquefaction, transport and storage, using established technology. However, the century-old Haber-Bosch process
for producing ammonia from hydrocarbon sources is responsible for two-percent of global CO2 emissions.
Alternative, ‘green’ ways of producing ammonia are being implemented around the globe. In Australia, Yara, the world’s biggest producer of ammonia, has
announced that it intends to build a demonstration plant to produce ammonia using solar power, near its existing world-scale plant in the Pilbara,
in Western Australia.
Yara hopes to begin production of carbon-free ammonia in 2019.
Hyundai launched its FCV program in 2000 and released the Tucson FCV in 2014. The company’s fifth-generation product, the Nexo, was released in South Korea
in March 2018 and is on sale in Europe and the USA.
Australia sees South Korea’s commitment to hydrogen fuel as an important trigger for ammonia exports. Last year, South Australia issued a report on green
hydrogen that included possible supply for South Korea’s future fleet of fuel cell transit buses.
The CSIRO plans to install at least two next-generation ammonia to hydrogen fuelling systems, one in Australia and one at an international location.