ARISTA-Neiker-TecnaliaThe Basque Institute for Agricultural Research and Development, Neiker-Tecnalia, has confirmed the capacity of Chlamydomonas acidophila microalgae to absorb ammoniacal nitrogen present in the effluent generated in the digestion of organic waste coming from the agri-food sector.

This algal strain, their research shows, can grow in organic waste liquids and assimilate the ammonium, which prevents the gas from being volatilized in the form of ammonia (NH3) and contaminating the atmosphere.

The decomposition process of agri-food waste in oxygen-free conditions produces effluent that has a high content of ammoniacal nitrogen – between 2 and 5 grams per liter. Significant quantities of this waste are produced on farms and biogas plants, among other facilities, so finding suitable methods for managing it and preventing the ammonia from being volatilized keeps it from ending up in aquifers and surface waters.

Chlamydomonas acidophila microalgae display characteristics suited to growing and reproducing in a medium that contains up to 50% of the liquid that comes from the decomposition of agri-food waste, as Neiker-Tecnalia researchers have been able to confirm, and have the capacity to develop in very acidic mediums (pH 2-3) and tolerate, to a high degree, the presence of heavy metals and high organic loads.

Neiker-Tecnalia, the public body that reports to the Sub-Ministry for Agriculture, Fisheries and Food Policy of the Government of the Basque Autonomous Community, is currently developing various lines of research devoted to identifying and subsequently assessing microalgae strains that are of commercial and environmental interest.