EnviTec relies on SEPURAN® Green membranes in Germany’s largest biogas plant

Source: press release, 6 July 2021

SEPURAN® Green membranes
SEPURAN® Green membranes (photo: Evonik)

At the EnviTec Biogas AG BioEnergie Park Güstrow (Germany), biogas will be liquefied into 9,000 tons of biomethane per year (Bio-LNG) beginning in the fall of 2022. The project of the biogas all-rounder based in Lohne and Saerbeck (Germany) is exemplary for supplying bio-LNG onsite as another immediately available renewable energy source in Germany. The climate-neutral fuel is made available for heavy-duty transport via the filling station networks of service station operators such as Liqvis and Liquind. In Germany’s largest biogas plant so far, plant operator EnviTec Biogas relies on Evonik’s patented SEPURAN® Green membrane technology for efficient biogas upgrading.

Liquefying biomethane and bio-CO2
In the future, the approximately 500 GWh biogas processing plant in Güstrow will process 150,000 metric tons of predominantly agricultural waste into high-purity bio-LNG. In addition, the carbon dioxide (bio-CO2) separated from the biogas will be liquefied and made usable and storable as a natural raw material.

With the multi-million conversion of the 31-hectare BioEnergie Park in Güstrow, EnviTec is relying on the proven SEPURAN® Green technology: “We interconnect the membranes using Evonik’s patented 3-stage process for maximum efficiency in biogas upgrading, replacing the already obsolete pressurised water scrubbing technology,” says Olaf von Lehmden, CEO of EnviTec Biogas AG. “For more than 10 years, we have been working with Evonik to implement biogas projects worldwide in various plant sizes and can look back on a success story that now includes more than 60 references.”

Since the product launch in 2011, Evonik has developed its membrane technology with selected partners into a new quality standard in biogas upgrading. The Group is making an outstanding contribution in the decentralised provision of biomethane as a climate-friendly energy source.

Biomethane – proven technology, locally available
Biogas can be easily upgraded to biomethane and used locally in liquid (bio-LNG) form as a climate-friendly fuel. The decentralised provision of bio-LNG shortens the transport distances of the fuel and reduces transport costs. The use of regionally available substrates makes it possible to provide the fuel from the region for the region. Furthermore, new jobs are created along the local value chain.

Compared to other alternatives in transport in the context of climate-neutral mobility, biomethane is already successfully in use today, accessible in relevant quantities, and makes a significant impact in the defossilisation of freight transport.

The environmental benefits of biomethane as a climate-friendly fuel are obvious. Vehicles powered by bio-LNG:

  • Reduce CO2 emissions by around 90% compared with fossil diesel and gasoline engines.
  • Release approximately 99% fewer particulate matter.
  • Reduce nitrogen oxide emissions by around 90%.
  • Emit around 50% less noise than a comparable diesel engine (source: Zukunft Erdgas e.V.).

The defossilisation of transport in general, heavy-duty transport in particular, is an important approach to achieving the German government’s climate target – i.e., reducing German greenhouse gas emissions by 55% by 2030 compared with 1990 levels. “In this context, biomethane, as an established and available renewable fuel alternative, could become one of the key technologies for the climate-friendly transport turnaround in Germany. The technology is already being used successfully in numerous commercial vehicles,” says Volker Wehber, head of the global SEPURAN® Green business at Evonik.

Biomethane – proven technology, locally available
The highly selective SEPURAN® Green hollow-fibre membranes from Evonik remove the carbon dioxide from the raw biogas with ease and efficiency, turning it into high-purity biomethane. The membranes are made of specially developed Evonik high-performance polymers that are highly resistant to pressure and temperature.

Compared with other biogas upgrading processes, such as pressurised water scrubbing, pressure swing adsorption, or amine scrubbing, Evonik’s membrane technology has significant advantages: it requires comparatively little energy and does not need any auxiliary materials or chemicals. It produces no waste or wastewater that would otherwise have to be treated and disposed of.