Assessment of the Energetic Potential of Different Fast- Growing Species in the Bogotá River Basin

Abstract

Biofuels are an important alternative to diversify the national energy system improving the sustainable level for supply the energy requirements of the country. Energy crops have become the new trend for several types of biofuels. Nevertheless, in Colombia this sector uses as raw materials first generation crops, despite the agricultural land available to implement fast-growing species. In a general way, there is a lack of information related to the energetic potential of native and foreign species in Colombia. Almost all previous works have been focused on residual biomass from agricultural sectors. This work includes a general evaluation in order to determine species stablished in Colombia and species not yet reported with potential to be energetically valorized. This evaluation was carried out using the Colombia’s Biodiversity Information System database (SIB by its Spanish acronym) and previous worldwide works of energetic crops reported in similar latitudes. In addition, physicochemical information such as the percentage of hemicelullose, dry matter, ashes, and apparent humidity was obtained. Eleven (11) families of crops were selected and compiled in twenty two (22) species and then were classified having into account soil type and crop requirements. The cultivation areas were calculated analyzing the Geographic Information System including the information related to crop requirements, protected zones, urban zones and fresh water sources. Specifically, in Cundinamarca were identified species related to families Fabaceae, Pinaceae and Poaceae. The species Arundo donax L. (Pinaceae family) has the higher specific area for this group of species with a value of around 213.000 hectares in the department of Cundinamarca which corresponds thirty five (35) percentage of the total area in the basin. Nevertheless, the energy potential calculated as a function of available areas and physicochemical properties is in the range of 18,000 TJ/year less than other species evaluated in this work. The technologies identified to carry out the energetic valorization of the crops are a function of their content of lignin, cellulose and hemicellulose. In this sense, families with a lignin content around 25 % (Salicaceae and Pinaceae) could be used as raw materials to gasification and pyrolysis processes and families with cellulose and hemicellulose content around 48 and 64 % (Myrtaceae and Poaceae) could be valorized through fermentation processes after a pretreatment of the biomass obtained in the Bogota´s river basin. In this case Furans could be a high value product. From them, high octane fuels can be obtained. In a general way, there is a huge potential in the department of Cundinamarca to implement energetic crops in, which can avoid food competition, contribute to sustainable development and improve the quality of life of the citizens.