Wastewater from pig farms could soon be treated with algae, resulting in reduced waste and a potential feed source, according to research conducted by Navid Moheimani, PhD, director of the Murdoch University Algae R&D Centre, Perth.
Untreated wastewater from pig farms contains extremely high levels of ammonia, which can be hazardous to humans, animals and the environment. Findings indicate that microalgae grown on the wastewater can remove ammonia and other nutrients. In addition, the microalgae’s ability to reduce the pathogen load in the wastewater means that the treated water can be reused.
Moheimani and his team have identified three different types of microalgae that can grow on untreated anaerobic pig wastewater. The algal biomass produced is potentially a protein-rich food source for pigs and other animals, although he said extensive testing would be required.
The discovery is a world first and offers a potentially cost-effective means of remediating pig farm-waste water while reducing the potential for groundwater contamination. Anaerobic digestion in lagoons or ponds on farms is currently the most common method used to process wastewater on pig farms.