Jorge Cristóbal

Prioritizing and optimizing sustainable measures for food waste prevention and management

Highlights • The waste hierarchy is not enough for prioritizing food waste prevention measures.• The methodology proposed prioritizes measures using LCA and mathematical programming.• The methodology identifies quick wins – actions with low cost and high impact avoided.• The relevance of the weighting set used in the prioritization is limited.• Targets for food waste prevention must be set at the level of environmental impact.

Towards more sustainable management of European food waste: Methodological approach and numerical application

Trying to respond to the latest policy needs, the work presented in this article aims at developing a life-cycle based framework methodology to quantitatively evaluate the environmental and economic sustainability of European food waste management options. The methodology is structured into six steps aimed at defining boundaries and scope of the evaluation, evaluating environmental and economic impacts and identifying best performing options. The methodology is able to accommodate additional assessment criteria, for example the social dimension of sustainability, thus moving towards a comprehensive sustainability assessment framework. A numerical case study is also developed to provide an example of application of the proposed methodology to an average European context. Different options for food waste treatment are compared, including landfilling, composting, anaerobic digestion and incineration. The environmental dimension is evaluated with the software EASETECH, while the economic assessment is conducted based on different indicators expressing the costs associated with food waste management. Results show that the proposed methodology allows for a straightforward identification of the most sustainable options for food waste, thus can provide factual support to decision/policy making. However, it was also observed that results markedly depend on a number of user-defined assumptions, for example on the choice of the indicators to express the environmental and economic performance.

Multi-objective optimization of the electricity production from coal burning

Abstract To minimize the environmental impact of electricity produced by clean coal combustion, several pollution control devices are proposed as Best Available Techniques (BATs). Reductions in particulate matter (PM), nitrogen oxides (NOx) and sulfur dioxide (SO2) emissions would reduce the global and local environmental impact but investment costs bottleneck their implementation. In this paper, a multi-objective optimization problem is formulated including economic, social and environmental metrics to support decision making in the selection of those pollution control technology devices that should be applied in practice. The design task is formulated as a bi-criteria mixed-integer nonlinear programming (MINLP) problem, the solution of which is defined by a set of Pareto points that represent the optimal trade-off between the two objective functions. Results show that investment strategies will differ when considering social or environmental objectives to be minimized.

Modelling and process integration of carbon dioxide capture using membrane contactors

Abstract A zero solvent emission process is proposed using a membrane device and an ionic liquid as a solvent; integrating a non-dispersive absorption-desorption process, gas compression, and transport to sequestration area analysis. The study is based on a model of a hollow fibre module formulated with a system of partial differential equations in axial and radial directions, depending of the Graetz (Gz), solvent selection (H) and Sherwood (S h ) numbers. Numerical absorption results showing carbon dioxide (CO 2 ) recovery costs are presented, comparing them with those obtained in an integrated conventional process where Monoethanolamine (MEA) is applied as absorbent liquid.