Waste management of biomass has become a critical issue in terms of global warming and contamination of Earth resources. The slash and burn of maize wastes or the uncontrolled burning of forestry wastes cause wildfires, smog and greenhouse gases. Another problem is the proper digestate handling from biogas plants. This biomass has a very high water content, which reduces dramatically the energetic efficiency of incineration plants when burned. Also, the amount produced is too high to use it as organic fertilizer. A biorefinery is proposed in this project that will take advantage of these lowcost materials to produce high quality activated carbon (AC). AC is used in a many applications that require high surface areas.