Supply Chain Modelling for the Economic and Life Cycle Analysis and Optimisation of Bioethanol First-generation Production Processes
Year: 2010
Type: dissertation
Abstract: In the last decade, we have been assisting to a global redefinition of the world energy system. Firstly motivated by severe concerns about environmental health and global warming, it found its real impetus in a more complex question. Although commonly considered as tightly related to oil depletion, it is rather a multifaceted interconnection of different issues, which could be generally labelled as the supply security question, and of which the oil shortage represents a contributing part. Thus, asking when oil runs out is not the only question and definitely not the main concern related to energy supply. As wisely stated by the Sheikh Ahmad Zaki Yamani about thirty years ago, “the Stone Age did not end for lack of stone, and the Oil Age will end long before the world runs out of oil”. In our opinion, this intriguing prediction represents the hot-spot of the question: how vital is it for policy makers to accelerate the end of the oil age and how that might be achieved? After a fierce debate centred on the most viable way to manage the transition, renewable energy sources were eventually indicated as a realistic alternative to the conventional fossil sources. In particular, biomass conversion into biofuels was promoted as the best suitable option within the transport sector. At the governmental level, ambitious policies were conceived to drive the transition toward the new frontier. For example, the EU commission was determinant in pushing its Members through the imposition of minimum blending quotas of biomass-based fuels within the conventional fossil-derived ones. The latest EU guidelines also fixed new environmental standards setting at 35% the minimum Greenhouse Gas (GHG) emissions savings to be performed by biofuels with respect to the fossil-based ones they are meant to substitute. Among the possible choices to reach the targets, bioethanol is currently acknowledged as the most appropriate solution for a short-term gasoline substitution, although during its history has known some discredits and oppositions by both the public opinion and part of the academic community. The core of the question stands in weather the ethanol production is actually capable to give the right answer in terms of energy supply security (as global warming mitigation and market penetration). Therefore, decision makers should be driven by specific tools capable of steering the design of the novel biofuels systems considering production costs and environmental impact minimisation (or profits and financial sustainability maximisation) as undisputed paradigms. They should also adopt wider approaches which go beyond the limited company-centric view of the business and extends the scope of the analysis at the entire Supply Chain (SC). Very limited work was found in literature addressing the use of quantitative methodologies for the strategic design of biofuels infrastructures. Therefore, the research project was thought to cover this lack of knowledge through the development an original methodology to embody the Supply Chain Management (SCM) tools application and mathematical programming within a biofuels SCs optimisation framework. Accordingly, the aim of this Dissertation was to contribute in providing for modelling tools capable of steering the design of first generation bioethanol SCs through a full set of optimisation features. The work focused on the development of Mixed-Integer Linear Programming (MILP) models to assist the policy-making on biofuels industry at strategic and tactical level. The final objective was to deliver a suitable design and planning tool based on the approaches commonly applied to SC strategic design and planning under economic, financial and environmental criteria. Agricultural practice, biomass supplier allocation (domestic or foreign), production site location and capacity assignment, logistic distribution and transport characterisation were simultaneously taken into account within the same modelling framework. This also included different features for spatially explicit siting of supply networks nodes, capacity planning and a stochastic formulation was implemented to handle the effect of market uncertainty. Finally, with concerns to the environmental impact of cultivation practice a further aspect was deepened by assessing and minimising the global warming effect of fertiliser application in cropping biomass. The economics of the entire network was assessed by means of Supply Chain Analysis (SCA) techniques, whereas the environmental performance of the system was evaluated in terms of GHG emissions, by adopting a Well-to-Tank (WTT). The emerging Italian corn-based ethanol was chosen as a demonstrative real world case study so as to assess the actual model capabilities in steering strategic policies on different interest level.
Author: Andrea Zamboni
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W126312953