BIO Gas - Bring It On

Christian Riemann, BASF SE, Germany

“Green energy” has been playing an increasingly important role, politically, in recent years. It is no coincidence that the number of biogas plants built over the last 10 years has also increased rapidly. Produced for decades on farms and landfills, biogas has now become an interesting feed for natural gas grids. Biogases are mostly burned in combustion engines to generate power and heat.

Unfortunately, biogases are often generated in remote locations and the produced heat cannot be utilized. This reduces the efficiency of the process by around half. In such cases, injection of the collected biogas into the natural gas grid, and burning the gas wherever it is needed, can be a more lucrative alternative.
Before injection into a grid, however, the raw biogas has to be turned into a clean bio-methane which meets the local grid specification. Unfortunately, the gas treating process must be customized to fit the particular type of raw biogas.

As “biogas” is an umbrella term, and encompasses very different types of gases (landfill, sewer gases and fermentation gases).  Most interest is currently centred on fermentation gases as these gases are “tailor made” and therefore can maintain a certain gas quality. This is an important advantage for standardized gas treating unit designs. This is an ongoing story - biogas is an interesting prospect