An Olive Tree Pruning Biorefinery for Co-Producing High Value-Added Bioproducts and Biofuels: Economic and Energy Efficiency Analysis

This work presents a conceptual design of an integrated biorefinery using olive tree pruning as feedstock. The biorefinery combines a state-of-the-art thermochemical technology for producing high value-added antioxidants with an energy self-sufficient biochemical platform for lignocellulosic ethanol production. These plants are integrated by exchanging energy and feedstock. The process and design parameters employed in the plant designs are based on the authors' own lab and pilot-scale data. The paper discusses the economic dilemma of using this feedstock for producing high valueadded products in small amounts versus producing large amounts of low-profit biofuels. The feasibility of this production strategy at medium scale is demonstrated via a technoeconomic analysis based on total production cost for each coproduct. Each plant is energy integrated, and the energy performance of the bioethanol plant is assessed by calculating the end-use-energy ratio. Both analyses are parameterized with respect to plant capacity (100-1500 t dry weight (dw)/day) and raw material price (20-100(sic)/ton dry weight).