Characterization of biogas and biomethane trace compounds: A critical review of advances in in situ sampling and preconcentration techniques.

Worldwide, the valorization of biogas, landfill gas and biomethane is gaining momentum as circular economies and energy transitions are triggered. Nevertheless, to sustainably integrate those gases into today's energy mix, their quality must be controlled regarding their major, minor and trace constituents to preserve the integrity of infrastructures wherein they are burned, transported or stored. Field gas sampling is the first and most critical step in the analytical chain to characterize the composition of such gases.

Novel field-portable high-pressure adsorbent tube sampler prototype for the direct preconcentration of trace compounds in gases at their working pressures: application to biomethane.

In Europe, renewable energy gases such as biomethane are aimed at substituting natural gas provided their stringent compliance to natural gas quality standards stipulating maximal levels of several chemical trace compounds (TC). Preconcentration is generally required to detect TC and inasmuch as biomethane is compressed for injection in the natural gas grid, preconcentration is commonly either done by collecting the bulk pressurized gas in a high-pressure cylinder or by first depressurizing it to collect a bulk volume in a gas sampling bag. Such whole gas samples are then transported to the lab and transferred to a preconcentration unit, entailing contamination and TC loss risks.