W. Alex Marvin

Optimal Supply Chains for Biofuel Production

Abstract Both environmental and economic performances are critical in the development of the biofuel industry for it to truly be a sustainable alternative to petroleum-based transportation fuels. In this chapter, that challenge is examined for a 9-state region in the Midwestern United States by formulating and solving a supply chain optimization problem with the competing objectives of maximizing profit (as Net Present Value) and minimizing greenhouse gas emissions. Recent life cycle analysis literature on biofuels is leveraged to quantify the impact of each activity in the biofuel supply chain. The resulting multiobjective mixed integer linear program is solved using an e-constraint approach that yields the Pareto Frontier of efficient supply chain designs. This allows for the identification of supply chain decisions that greatly reduce greenhouse gas emissions for minimal economic losses.

Optimization of a Distributed Small Scale Biodiesel Production System in Greater London

Abstract In this paper, we explore the economic feasibility of a distributed network of biodiesel production facilities installed in Greater London area of the UK, in order to take advantage of the availability of waste cooking oil, concentrated demand for biodiesel and economies of “mass” produced capital equipment. The biodiesel facility location problem was formulated as a mixed integer linear program (MILP) with the objective to maximize system-wide net present value. Total capital investment was described as a function of installed capacity using a general piecewise linear function, allowing for the effect of capital cost reductions of mass produced capital to be addressed. This system of small scale distributed biodiesel production is shown to be economically feasible and could be seen as a possible step towards a more locally focused fuels and energy supply network.

Optimization and Analysis of Chemical Synthesis Routes for the Production of Biofuels

Abstract In this work we extend a recently proposed method to concurrently select biofuel blends which satisfy ASTM standards and their optimal synthesis routes by using thermochemistry based post-processing analysis to compare these routes. Gas phase thermochemistry, estimated from group additivity, was used to calculate the equilibrium extent of reaction for each synthesis step. Situations of reaction, phase, and site coupling were subsequently identified to overcome equilibrium limited steps and reduce the number of reaction systems required. This method can aid process designers in screening and ranking large numbers of potential biofuel candidates and synthesis routes simultaneously from an energetic, thermochemical, economic, or kinetic standpoint.