Biogas Upgrading

Upgrade to Carborex®MS

With a Carborex®MS your biogas will be upgraded to pure methane. The biomethane can be supplied to the national gas grid, or be compressed to Natural Gas to be used as vehicle fuel. DMT’s Carborex®MS in Poundbury, UK, was the first commercial biogas upgrading system in the UK, and the first in Europe in 2012. DMT is now the largest producer of biogas upgrading facilities in the world with membrane technology. In 2016 we have installed our biggest plant in the USA.

  • 99,5% methane recovery
  • Highest uptime
  • Easy & Intelligent interface
About the products Market solutions
Upgrade to Carborex®MS

This is a great contribution to the creation of circular economies and energy independence. Out of waste streams, clean gas can be provided to houses as well as fuel for transport and mobility. Biomethane is fossil-free and considered the energy of the future. What is biogas?

Biogas upgrading

DMT has developed a technology for biogas upgrading using membranes, Carborex®MS IThe technology separates CO2 from the valuable methane by using innovative membrane technology. This process has the advantages of being a dry process, no chemicals involved and having low energy consumption and it is easy to operate. The whole system is built on a skid or in a container, which results in a small footprint and an easily transportable system. The Carborex®MS is, therefore, a cleantech solution with low operational costs (OPEX).

Carborex®MS – Biogas Upgrading

The repurpose of organic waste plays a key part in reducing our dependence on fossil fuels and solving a growing environmental problem. With our challenge to create a clear and prosperous future, DMT Environmental Technology has proven its expertise in biogas upgrading and compressing or liquefying biomethane.

Pre-Treatment and Compression

As mentioned before, biogas consists mainly of methane and carbon dioxide. However, there are still some other components that must be removed before entering the membranes. In many cases, biogas contains H2S, mercaptans and terpenes, which all must be removed. The gas also contains water, which, preferably, is removed before entering the membranes. As a solution, the Carborex MS contains a pre-treatment section where these components are removed. The next step to pure biomethane is to compress the gas by up to 16 bar by a compressor. The pressure optimizes the separation of methane and carbon dioxide by increasing the permeability of the membrane.


The membranes inside the Carborex®MS are built up of hundreds of hollow fibres, which look like spaghetti. The hollow fibres are non-porous and made of polymers. The separation of methane and carbon dioxide occurs because of the difference in diffusivity rates of the two. The molecular structure of carbon dioxide allows this molecule to pass through the polymer material faster than molecules of methane. Biogas enters the membrane inside the hollow fibres. The separation results in a carbon dioxide rich stream at the permeate side of the membrane and a methane-rich stream at the retentate side of the membrane.

Multistage vs. Single Stage

One membrane contains hundreds of hollow fibers. Depending on the raw biogas inlet flow, the number of membranes inside the Carborex®MS varies. We call one set of membranes a stage. While a two-stage membrane configuration can reach a methane recovery of up to 97%, the most common configuration is a three-stage membrane configuration which reaches 99,5% methane recovery. Fundamental in most biogas upgrading projects.

On the permeate side of the membrane, thanks to intelligent recycle loops, the methane concentration in the carbon dioxide stream can be reduced to less than 0.5%.

Terminology regarding membrane separation technology:
Permeate: Gas that has traveled through the porous membrane
Retentate: Gas that is retained and collected at the end of the membrane fiber
Selectivity: Ability of a membrane to predictably meet required separation performance expectations

Easy Operation

The Carborex®MS is a modular, easily transportable system with a small footprint. The whole system is started up with one simple touch of the start button. The system is robust, stable and requires very little maintenance. Because it is a dry process, no after-treatment of waste streams is required.

End Products

The upgraded biomethane from the Carborex®MS can be used for several purposes. Since biomethane is a replacement for natural gas, it can be injected into the natural gas grid. If no gas grid is available, the gas can be used as a transportation fuel. In this case, the gas is compressed to 250 bar as Bio-CNG or liquefied (-198 degrees Celsius) as Bio-LNG.

Liquefied Natural Gas (LNG)

Liquefied Natural Gas, from the liquefaction of high-quality biomethane, is the only biofuel better for the environment than its fossil counterpart. Research shows that Bio-LNG is the most cost-effective fuel available today for the reduction of carbon dioxide emissions and, therefore, an ideal investment for reaching climate goals. By combining clean combustion, easy transportation, flexibility and higher security (both in terms of reserve capacity and stability of price), Bio-LNG is gaining worldwide status as the fuel of the future.

Renewable Fuels

Producing natural gas in a sustainable way can be done by upgrading biogas. Biogas is a gas produced by the fermentation of biological waste products. The two main components of this resulting gas are methane (CH4) and carbon dioxide (CO2). Upgrading means that the methane is separated from the carbon dioxide, resulting in a very pure methane gas flow. Unlike biodiesel and bioethanol, this biomethane has better properties than its fossil counterpart natural gas.

Jan Kruit, Area Sales Manager

Jan Kruit, Area Sales Manager

Jan has been with DMT since 2009. At the forefront of the European biogas market, Jan’s focus is on key account and commercial partner development. He has a background in chemical engineering and product development.

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