Introduction

Mill wastewater, when properly treated, can be used to produce a gas mix rich in hydrogen, CO2, methane, CO and other gases, useful for energy purposes. This patent is about the development of a process for olive mill wastewater treatment, allowing to produce a gas mix rich in hydrogen and methane.

Technical features

The patent registered by ENEA is about the development of a process for olive mill wastewater (OMW) treatment, allowing to produce a gas mix rich in hydrogen and methane: specifically, approximately 18 m3 of hydrogen have been produced from 1 m3 of vegetable water during laboratory tests. During this process, the OMW are first filtered and then conveyed into a catalytic reactor, where the gas mix is produced through a reforming reaction. If a membrane reactor is used, ultra-pure hydrogen can be directly separated obtaining higher reaction yields. The energy needed for the reforming process, heavily affecting the management costs, can be supplied by burning olive pomaces and the gases so produced, and by the thermal recoveries of process facilities.

Possible Applications

• Small- and medium-sized olive mills.

Advantages

• Reduction of phenols content of OMW;
• Producing fuel gases;
• Use of wide-application and low-cost components and technologies;
• Low management costs;
• Thermal recovery;
• Application to other biomass types.