In Part One of a two-part gasworld TV webinar series, sponsored by Evonik, air gases were the main topic of discussion. Forming the ‘backbone’ of the industrial gas sector, oxygen nitrogen, argon, and air separation units (ASUs) form an integral part of not just industry, but the sustenance of life itself.

Hosted by gasworld Global Managing Editor, Rob Cockerill, Part One explored all things additive manufacturing (AM) with guest Pierre Foret, Director of R&D at industrial gas company Linde, hydrogen production and its role in driving growth of large-scale ASUs with Stephen B. Harrison, Managing Director of sbh4, and medical oxygen production in the wake of a global pandemic with Bernard Zenou, President of NOVAIR.

Pierre Foret kicked off the webinar by discussing the topic of additive manufacturing (AM).

Calling AM a ‘very innovative way’ of making objects, Foret defined it as using a digital model to form an object by adding material layer by layer. The technology is able to utilise various different materials and energy sources.

“There is one specific technology that is dominating the scene for the last five years. The technology is called laser-powder bed-fusion and uses very fine metallic powder and a laser to create parts,” he said.

Stating that this technology is ‘revolutionising’ the way parts are being designed and produced, he explained that it allows for designs that are impossible to do with other methods.

He added, “The parts can be smarter, more efficient, lighter than some of our other applications.”

“The production is fast and the supply chain is much smaller because you don’t need to source many different parts from all over the globe. You can easily customise parts, which is one of the main reasons why additive manufacturing is so successful in medical industry.”

When asked about the size of the opportunity for AM in industry as a whole and also the gas business, Foret was enthusiastic, stating that the metal AM market in 2020 was worth more than $8bn.

“The market is expected to reach $20bn in 2025, and this is only the metal additive manufacturing market. There is also the polymer market, but the gases are less important in that area for the gases business.”

Foret then went on to say that the opportunities for the gas industry are multiple and that Linde wish to support the growth and industrialisation by developing innovative solutions.

“One example, we are launching this year a new process gas that we have developed with a leading company from the medical industry. This process reduces the formation of by-products during printing, less by-products means higher quality and faster printing.”

“I believe we should embrace this technology to rethink the way we design and produce parts that we use in our plants.”

Sharing his view on sustainability and additive manufacturing, Foret admitted that AM is not the solution to everything and that, avoiding ‘greenwashing’ the process, the technology offers advantages that can be harnessed when sustainably producing goods.

“We can build parts that are lighter and therefore use less material, less resources. We can produce parts that are smarter and better, making it more efficient and more sustainable.”

Hydrogen production and large-scale ASU growth

Next up was Harrison, who began by discussing the ramping up of hydrogen production, stating that ‘we’ are leaping ‘orders of magnitude’ from mega-scale to giga-scale projects and that scaling up needs to occur for hydrogen production from natural gas and coal.

Giving an example, he suggested the H2H Saltend project planned to support decarbonisation of the Humber industrial cluster in East Yorkshire proposes a 600 Mega Watt (MW) autothermal reactor to make hydrogen rich syngas.

“To enable 600 MW of hydrogen production the air separation unit would need to produce about 1200 tonnes of oxygen per day, that would make it one of the largest in the UK.”

Harrison also mentioned, through the production of hydrogen from natural gas, carbon dioxide (CO2) is generated. To offset these emissions focus will be placed on the production of ‘blue hydrogen’, which requires capturing the CO2 and storing it using carbon capture and storage (CCS).

“To qualify for the ‘blue’ hydrogen label, the captured CO2 must be sent to a CCS scheme where it is permanently stored underground in natural geological formations,” said Harrison.

He recognised that global CCS schemes, despite being established, have never been ‘optimised synergistically’ as an integrated process and that a paradigm shift is required for scaling up of blue hydrogen production, meaning that the entire system must be optimised in a holistic way.

Harrison also elaborated on large-scale ASU growth, saying coal and petcoke gasification must be considered as a pathway to making hydrogen-rich syngas.

He continued, “Gasification has been used for more than 100 years to produce syngas. Gasification like autothermal reforming POX, requires oxygen. The use of pure oxygen, instead of air, is beneficial for precise control of the oxidation chemistry and avoids costly flue-gas de-NOx systems.”

The process also makes the integration of CCS more cost-effective by avoiding large-scale nitrogen processing from the air.

When asked about challenges faced with dramatic ASU growth, Harrison emphasised financing and risk-mitigation, saying, “Raising the capital make major ASU investments will be a challenge.”

“Safety beats in the heart of industrial gases but there are inherent hazards, and the challenge is to minimise the risk.”

“These points might cast some minds back to the horrific ASU explosion that took place at the GTL plant in Bintulu, Malaysia in 1997.”

“Reflecting on these issues is a stark reminder that ASU design and operation must be left in the hands of industrial gases experts to ensure that the Giga-scale production of oxygen to make hydrogen is done safely.”

Medical oxygen and on-site generation

The final speaker, Zenou, brought a wealth of knowledge as President of NOVAIR, one of the first companies to introduce the oxygen generator as a source of medical oxygen to supply European hospitals.

With the Covid-19 pandemic causing widespread disruption across the health industry, the availability of medical oxygen became a hot topic. Giving his thoughts on the past 18 months, Zenou said that even though oxygen has been available, it is not necessarily available where it is needed due to lack of transport, logistical issues, and the sheer volume required by hospitals.

“It is the opportunity now to show how good this solution could produce onsite oxygen. The technology is quite mature, technology save the oxygen from the air has existed for around 20, 25, 30 years,” he said.

Assuring that the technology is safe and reliable for hospitals to use, Zenou said that pressure swing adsorption (PSA) technology is a relatively simple technique which could be used everywhere, with only electricity being required.

“PSA oxygen can produce from five to 50 cubic metres per hour, with a maximum of around 100 cubic metres per hour. This is the range of oxygen supply and this is exactly what hospitals and health facilities required.”

Zenou encouraged further adoption of on-site oxygen production saying that there are no disadvantages and that there is also an environmental element at play.

“When you produce on-site, you have prevented any transportation, it means that your contribution to that is very much to the planet. There are no emissions due to the transportation of the units of the product, this is an additional advantage,” he stated.

With the ongoing pandemic exposing failures in the global supply of medical oxygen, Zenou was asked if, since early 2020, we’re seeing real change in the medical market.

“I think that in the medical market we are, we have the pandemic situation where the need for oxygen is very high everywhere. The volume of oxygen needed by an Indian hospital is multiplied by a factor of six to eight, demand is extremely, extremely high.”

“We believe that the solution is this technique, this technology will be required for the future.”

This technology could be further developed following the news that NOVAIR recently received a €26m investment from a global investment group.

Zenou elaborated upon the news, saying, “We are planning for the future, a large demand, and we need to invest more in our production capacity.”

Stating that scaling up needs to occur in order to increase its oxygen production capacity at the company’s sites in France and Italy, he went on to say that each part of the system requires further investment.

“The oxygen generator is the heart of the system but it needs other equipment, it needs compressors, the filtration system, the monitoring system. It is continuously analyising because in our system we provide the means to analyse the quality of oxygen continuously onto the user, this ensure they have the good quality oxygen.”

If you enjoyed this week’s webinar focusing on air gases, don’t forget to register for Part 2 at

For more information on additive manufacturing, find previously published content here and here.