Optimum Utilization of Jatropha Seedcake Considering the Energy, Water and Food Nexus

Biofuel production has attracted significant attention from researchers and policymakers as a carbon-neutral source of energy. However, corresponding intensive land and water requirements have hindered the advancement of the biofuel industry. Consequently, second-generation biofuels from non-edible biomass have been promoted as suitable alternatives. In this context, the Jatropha curcas has proved to be a promising feedstock for various types of biofuels due to its competences over other oil-bearing crops, and its suitability to grow in non-arable lands with minimal water and energy requirements. In addition to utilising Jatropha oil as a source of energy, Jatropha seedcake has been used to produce energy and food-related products. Although, there are several processing pathways of seedcake which have been investigated, there are no conclusions on the optimum overall pathway. Meanwhile, the Energy-Water-Food (EWF) Nexus approach has recently become an important tool to ensure efficient and optimum management of the three vital resources by considering the inter-dependencies amongst them. It can also guide decision making in terms of identifying optimal processing and utilisation pathways. Therefore, this study presents an analysis of different production routes, and defines the optimum utilisation of Jatropha seedcake, by ensuring that the highest possible net energy, water and food are achieved. Required data are obtained via Aspen Plus’ simulation of potential processes, while MATLAB is used to develop the mathematical optimisation model. The model produced 77 different solutions, with gasification being the dominant pathway in most of the given solutions, followed by livestock feed and fertilizers production.