Optimal experimental design in the evaluation of food packaging compliance with safety regulations

11th IFAC Symposium on Dynamics and Control of Process SystemsIncluding Biosystems DYCOPS-CAB 2016 — Trondheim, Norway, 6—8 June 2016The determination of diffusivity of compounds that can be transferred from packaging into food products is a keystone to ensure consumer’s safety. However, no clear guidelines exist as how the diffusion experiment should be designed in order to maximise the accuracy of the estimated parameter. With the perspective of optimal experimental design, a methodology to estimate the diffusivity of a migrating compound in a polymer is presented, both for global methods (that measure the overall concentration) and local methods (that measure the profile of concentration along the polymer thickness). To demonstrate the methodology, real experimental data (transfer of Uvitex OB from linear low-density polyethylene) are used, and the OED based methodology is benchmarked against other heuristics. It is seen that, although the OED methodology outperforms the rest of methodologies when good initial guesses are available, its performance becomes deteriorated when gross over- or underestimations of the true value are madeThe author would like to acknowledge the reviewers for very constructive comments that have contributed to improve this work. This work is funded by the People Program (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007-2013 under REA agreement 627475 (GREENCOST). The author belongs to the Galician Competitive Research Group GRC 2013-032, programme cofunded by FEDERS

H2020 Project ENERWATER – Quantification and reduction of energy expenditure in WWTP

Waste Water Treatment Plants (WWTPs) account for more than 1% of consumption of electricity in Europe, one of the largest shares of energy use among public industries. The aim of ENERWATER is to provide measuring tools to quantify the energy consumption of WWTPs and to elaborate the standards to compare and ultimately optimise the operation of WWTPs. The methodology is demonstrated on 50 WTTPs, whose energy consumption is thoroughly monitored. ENERWATER goals will be reached by i) defining the concept of energy efficiency in WWTP and the performance indicators suitable for its quantification; ii) standardising the methods for measuring energy consumption in order to ensure that comparable figures are obtained; iii) using data treatment tools to not only quantify but also diagnose the reasons for energy inefficiency and iv) proposing a global index that measures the energy efficiency of a WWTP. All these steps will eventually be part of a general methodology that can be the draft of a standard for measuring energy efficiency in WWTP. ENERWATER is a three-year activity that involves 9 partners (universities and companies) from 4 European countries (Germany, Italy, Spain and the United Kingdom). To ensure a fast transfer of results to the relevant actors, ENERWATER puts in contact research groups, SMEs, utilities, city councils, policy makers and industry beyond the project consortium. These actions should bring European Water Industry a competitive advantage in new products development and a faster access to markets by facilitating evidence of energy reduction, thereby fostering adoption on new technologies.This project is carried out with financial support from the H2020 Coordinated Support Action ENERWATER (grant agreement number 649819): www.enerwater.eu. Although the project's information is considered accurate, no responsibility will be accepted for any subsequent use thereof. The European Community accepts no responsibility or liability whatsoever with regard to the presented material, and the work hereby presented does not anticipate the Commission's future policy in this area. Authors belong to the Galician Competitive Research Group GRC 2013-032, programme co-funded by FEDER, and to the strategic aggregation CRETUS (Centre for Research in Environmental Technologies), AGRUP2015/0

Computer-Aided Design of Active Packaging/Food System for extended shelf life

Common dynamic models of active packaging are focused on the mass transfer of the antimicrobial agents. Nevertheless, the interaction of the antimicrobial agent with the food microorganisms is usually neglected, despite being critical to optimise the food safety and quality. In this work, we propose a dynamic model simulating the dynamics of carvacrol and its inhibition by Listeria monocytogenes in an active packaging system. Carvacrol is an antimicrobial agent allowed as a food additive and Listeria monocy- togenes is the major psychrotrophic pathogen in food. The model can be exploited to study different aspects of the food quality and safety, such for example the maximum load of Listeria before packaging and the concentration of carvacrol to guarantee food quality and safety standard

Energy efficiency in wastewater treatment plants: A framework for benchmarking method selection and application

Utilities produce and store vast amount of data related to urban wastewater management. Not yet fully exploited, proper data analysis would provide relevant process information and represents a great opportunity to improve the process performance. In the last years, several statistical tools and benchmarking methods that can extract useful information from data have been described to analyse wastewater treatment plant (WWTP) energy efficiency. Improving energy efficiency at WWTPs is however a complex task which involves several actors (both internal and external to the water utility), requires an exchange of different types of information which can be analysed by a broad selection of methods. Benchmarking method therefore must not only be selected based on whether they provide a clear identification of inefficient processes; it must also match the available data and the skills of those performing the assessment and objectives of stakeholders interpreting the results. Here, we have identified the requirements of the most common benchmarking methods in terms of data, resources, complexity of use, and information provided. To do that, inefficiency is decomposed so that the analyst, considering the objective of the study and the available data, can link each element to the appropriate method for quantification and benchmarking, and relate inefficiency components with root-causes in wastewater treatment. Finally, a framework for selecting the most suitable benchmarking method to improve energy efficiency in WWTPs is proposed to assist water sector stakeholders. By offering guidelines on how integrates and links data, methods and actors in the water sector, the outcomes of this article are expected to move WWTPs towards increasing energy efficiencyThis work was financially supported by ENERWATER Coordination Support Action, as part of European Union's Horizon 2020research and innovation programme under grant agreement No 649819. A. Hospido and M. Mauricio-Iglesias belong to a Galician Competitive Research Group (GRC) under reference ED431C-2021/37, a programme co-funded by the FEDER (EU)S

Benchmarking energy use in wastewater treatment plants

IWA Pi Conference, May 15th 2017, ViennaAcademic research on benchmarking energy efficiency predominately focuses on two main streams of alternatives techniques: parametric and nonparametric. Since there is no agreement on the consistency of their estimates, the purpose of this paper is to investigate whether parametric ordinary least squares (OLS) and nonparametric data envelopment analysis (DEA) generate consistent wastewater treatment plant (WWTP) efficiency estimates. Our findings confirm that energy efficiency is function of several variables, including operational and exogenous factors. For it, a two-stage DEA process was followed in order to observe the overall effect produced by operation size and environmental conditions on efficiency index estimated by DEA. Based on the results of our analysis, the simply DEA in the variable return to scale assumption may not reflect the real efficiency of a WWTP. On the contrary a good consistency between OLS and 2-stage DEA was found. Conclusion of this study is that WWTP efficiency estimates may be sensitive to the method employed, and the use of multiple approaches for robustness checking is recommende