When DME is produced from sustainable raw materials, renewable and recycled carbon, it has a significantly lower greenhouse gas footprint than LPG and carbon-rich fossil fuels such as fuel oil and coal. It can be used alone or mixed with LPG to reduce emissions for homes, businesses and industry not connected to the gas grid. In Europe alone, this is a huge market - about 20 million tonnes of LPG are used for energy applications in Europe every year.
From fossil to circular carbon
One of the technologies developed by TNO is SEDMES (Sorption Enhanced DME Synthesis) by which CO2 and (green) hydrogen can be converted into DME in one step. The CO2 can be captured directly from outdoor air, or captured from biogenic residual streams from companies on site, after which it is converted with high efficiency.
The traditional conversion method is limited by being an equilibrium reaction. One-step conversion is possible but yields a yield of at most 10%. Because water is removed by adsorption during the process in SEDMES, efficiencies as high as 85% are achieved. The result is a robust one-step process, immediately a much purer product and maximum yield. Meanwhile, TNO has developed a mobile pilot unit built where industry can learn about the technology.
Billion people 'off-grid'
And that caught the attention of Dimeta, a joint venture established in 2022 between Dutch SHV Energy and US-based UGI International. Dimeta aims to produce renewable and recycled dimethyl ether (DME), as a sustainable low-carbon liquid gas, on a large scale to accelerate decarbonisation.
The company has calculated that one billion people worldwide live 'off-grid', or in homes that do not have a gas connection. They rely on oil and coal for heating and cooking. In Europe, for remote places, this is usually propane and butane gas. Furthermore, in all kinds of business sectors that rely on LPG, DME is an alternative that leads to significantly less CO2-emissions. This also applies to road transport.
Dimeta and TNO are collaborating in several projects to scale up sustainable technologies at industrial scale and to produce advanced biofuels and renewable fuels of non-biological origin. As part of the BUTTERFLY consortium, to demonstrate flexible, efficient and low-cost production of renewable DME and synthetic natural gas. In the POWERED consortium to develop technology for the production of DME from wind power and other renewable energy sources.
Key link in decarbonisation
"SHV Energy and TNO have been working together for some time," says Lizzie German, Investment and Technology Manager of Dimeta. "This is how we learned of the SEDMES technology, which is extremely valuable for us as a supplier of DME. We aim to produce around 300,000 tonnes a year by 2027. We are building a plant in the UK to be operational by 2025 and there are plans for production in the US."
"There is a great need for renewable energy to reduce greenhouse gas emissions. DME can make an important contribution to this through use in households, agricultural businesses. industry and transport. In Europe, it is a clean replacement for the widely used propane and butane. Industry will have to work on decarbonisation in the coming years and DME is a key link in that. And the technologies TNO is developing will help us succeed in that market."
Efficient and cheap
Expert Jan-Willem Könemann of TNO foresees DME taking off in the coming years, especially now that it has been shown to be efficient and relatively cheap to produce.
"The core of the story to meet the climate goals is always both using renewable energy and reusing raw materials. DME fits into that very nicely with the SEDMES technology. We have to get rid of fossil, but the question is then how we continue to make all those products that have traditionally been carbon-based. Then you quickly talk about the combination of CO2 and hydrogen."
"Thus, many more products and applications can be imagined with DME. It can replace diesel and LPG but also serve as a building block for many valuable chemicals that are now fossil-based. DME can be further dewatered to ethylene, a raw material for many materials we use in our daily lives. If we eventually run out of fossil carbon sources for our products, we should definitely commit to CO2 as feedstock for DME. At TNO, we are constantly working to improve the technologies needed for this," said Jan-Willem Könemann.
The transition to a post-fossil society is creating scarcity of carbon resources for many products we use every day. Purpose of FutureCarbonNL, a consortium of companies, business organisations, research institutions and the Ministry of Economic Affairs, is to realise a leading carbon-tech sector in the Netherlands. The aim is to develop conversion technologies that reduce CO2 and exploit CO as a circular raw material, to use electricity, hydrogen or (solar) light to make new products such as materials, fuels or (animal) food. TNO has long been developing new technologies that will help make the Netherlands a global leader in Carbon capture and utilisation (CCU).
Webinar: CO2 reduction and green carbon in industry from waste streams
Sign up for the webinar on 21 June 2023 where TNO experts will present three unique technologies that convert carbon and CO2 into sustainable products. Click here For programme and registration.
This article previously appeared on www.tno.nl