VATIS UPDATE Article

Scientists from the Institut de Science des Matériaux de Mulhouse (IS2M), France, have successfully converted the wastewater from olive oil production into a green biofuel. To create oil, olives are crushed and mixed with water in mills. The oil is then separated out of this mixture, and dirty water and solid residue discarded. The wastewater created can pollute waterways, reduce soil fertility and trigger extensive damage to ecosystems.

In Mediterranean countries, where 97% of the world’s olive oil is produced, close to 8 billion gallons of the polluting wastewater is produced each year. Mejdi Jeguirim from IS2M and colleagues have taken a different approach, developing a method to convert olive mill wastewater (OMW) from a polluter into sustainable products such as biofuel, biofertiliser, and safe water for use in agricultural irrigation.

According to the American Chemical Society, the researchers ­embedded OMW into cypress sawdust, another waste product common in the Mediterranean. This mixture was then rapidly dried and the evaporated water collected to be used to safely irrigate crops. The OMW sawdust was then subjected to pyrolysis, where organic material is exposed to high temperatures in the absence of oxygen.