Hydrogen and its use in cement production has been adding a dash of colour to the industry news in recent weeks. Last week, Lafarge Zementwerke, OMV, Verbund and Borealis signed a memorandum of understanding (MOU) to plan and build a full-scale unit at a cement plant in Austria to capture CO2 and process it with hydrogen into synthetic fuels, plastics or other chemicals. This week, Air Products and ThyssenKrupp Uhde Chlorine Engineers (TUCE) signed a strategic agreement to work together in ‘key regions’ to develop projects supplying green hydrogen. Both of these developments follow the awarding of UK government funding in February 2020 to support a pilot project into studying a mix of hydrogen and biomass fuels at Hanson Cement’s Ribblesdale integrated plant.
As the title of this column suggests there is an environmental colour code to describe how hydrogen is made for industrial use. This is a bit more codified than when grey cement gets called ‘green’ but it pays to remember what the energy source is. So-called ‘green’ hydrogen is produced by the electrolysis of water using renewable energy sources such as hydroelectric or solar, ‘Grey’ hydrogen is made from steam reforming using fossil fuels and ‘Blue’ hydrogen is similar to grey but has the CO2 emissions from the fuels captured and stored/utilised. Price is seen as the main obstacle to wider uptake of hydrogen usage as a fuel in industry although this is changing as CO2 pricing mounts in some jurisdictions and the connected supply chain is developed. A study by BloombergNEF from March 2020 forecasted that green hydrogen prices could become cheaper than natural gas by 2050 in Brazil, China, India, Germany and Scandinavia but it conceded that many barriers would have to be overcome to get there. For example, hydrogen has to be manufactured making it more expensive than fossil fuels without government policy support and its, “lower energy density also makes it more expensive to handle.”
The three recent examples with respect to the cement industry are interesting because they are all exploring different directions. The Lafarge partnership in Austria wants to use hydrogen to aid the utilisation side of its carbon capture at a cement plant. The industrial suppliers, meanwhile, are positioning themselves in the equipment space for the technology required to use hydrogen on industrial plants. Secondly, ThyssenKrupp has alkaline water electrolysis technology that it says it has used at over 600 projects and electrochemical plants worldwide. Air Products works with industrial gas production, storage and handling.
Finally, the Hanson project in the UK will actually look at using hydrogen as a partial replacement for natural gas in the kiln combustion system. A Cembureau position paper in mid-2019 identified that the challenges to explore in using hydrogen in cement production included seeing how its use might affect the physical aspects of the kiln system, the fuel mass flows, temperature profile, heat transfer and the safety considerations for the plant. Later that year a feasibility study by the Mineral Products Association (MPA), Verein Deutscher Zementwerke (VDZ) and Cinar for the UK government department that is funding the Hanson project concluded that a hydrogen flame’s high heat in a burner alone might not make it suitable for clinker formation. However, the study did think that it could be used with biomass to address some of that alternative fuel’s “calorific limitations” at high levels. Hence the demonstration of a mixture of both hydrogen and biomass.
That’s all on hydrogen but, finally, if you didn’t log into yesterday’s Virtual Global CemProducer 2 Conference you missed a treat. One highlight was consultant John Kline’s presentation on using drones to inspect refractory in some hard to reach places. Flying a camera straight into a (cool) pyro-processing line was reminiscent of a science fiction film! Global Cement has encountered the deployment of unmanned aerial vehicles in quarry and stockpile surveys previously but this was a step beyond.