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The potential improvement in methane recovery and reaction kinetics from different mixes of potato peel (PP) and pig manure (PM) in a single stage anaerobic co-digestion/mono-digestion process was investigated in a laboratory study. The highest methane yield of 231 mL/g [TCOD.sub.added] was observed in the 50:50 mix of potato peel and pig manure. Compared to the mono-digested substrates, co-digestion of PP and PM at 75:25, 50:50, and 25:75 synergistically improved methane yield by 17%, 25%, and 11%, respectively. The co-digested mixes also produced methane at a faster rate, with the fastest methane production rate occurring at the 50:50 mix. Thus, co-digestion of potato peel and pig manure enhanced the methane yield and reaction kinetics. Hence, co-digestion rather than mono-digestion should be actively considered when a carbon rich waste (such as potato peel) and nutrient rich waste (such as pig manure) are available within reasonable proximity. Key words: anaerobic digestion, mono-digestion, co-digestion, methane yield, reaction kinetics. L'amelioration potentielle de la recuperation du methane et de la cinetique de reaction a partir de differents melanges de pelures de pomme de terre (PP) et de fumier de porc (FP) dans un processus de co-digestion anaerobie/mono- digestion en une seule etape a ete etudiee dans le cadre d'une etude en laboratoire. Le rendement de la production de methane le plus eleve, soit 231 mL/g de demande chimique totale en oxygene ajoutee, [TCOD.sub.added], a ete observe dans le melange 50:50 de PP et de FP. Par rapport aux substrats mono-digeres, la co-digestion de PP et de FP a 75:25, 50:50 et 25:75 a ameliore de maniere synergique le rendement en methane de 17, 25 et 11 %, respectivement. Les melanges co-digeres ont egalement produit du methane a un rythme plus rapide, le taux de production de methane le plus rapide se produisant au melange 50:50. Ainsi, la co-digestion des PP et du FP a ameliore le rendement en methane et la cinetique de reaction. Par consequent, la co-digestion plutot que la mono-digestion devrait etre activement envisagee lorsqu'un dechet riche en carbone (comme la PP) et un dechet riche en nutriments (comme le FP) sont disponibles a proximite raisonnable. [Traduit par la Redaction] Mots-cles : digestion anaerobie, mono-digestion, co-digestion, rendement de la production de methane, cinetique de reaction., Introduction The increase in world population and economic growth has led to a corresponding increase in energy consumption and organic waste generation. Energy demand is projected to further increase by [...]

The Canadian Society for Civil Engineering in its Vision 2020 statement identified sustainability in infrastructure as a core element for the civil engineering profession. However, what is sustainable infrastructure and more importantly, how can it be assessed? This paper uses stormwater infrastructure as its primary example to explore these issues, reviews issues with stormwater infrastructure in Canada, and critically examines current sustainability assessment methods. Two groups of problems are identified. The first group concerns issues related to economic, institutions, population growth, ecological, and health and safety. The second group examines the uncertainties in impact prediction associated with climate change effects as well as health impacts on the user. Sustainability evaluation methods (ranking, sustainability indicators, footprint, metabolism, extended metabolism, life cycle assessment), performance assessment tools, infrastructure report card, and the public infrastructure engineering vulnerability committee protocol for climate change assessment are then reviewed. Current methods of assessing infrastructure mostly focus on the functional aspects of the system with resource use reduction as the primary objective. However, they do not explicitly concentrate on resiliency and long-term sustainability, nor do they consider the associated health implications and change management capabilities for long-term sustainability. A new comprehensive framework would be required to assess broad, emerging issues related to infrastructure. Key words: stormwater, urban water, infrastructure, climate change, sustainability assessment, gap analysis, resource minimization, public health, change management. Dans son enonce Vision 2020, la Societe canadienne de genie civil a identifie la durability des infrastructures comme element essentiel a la profession d'ingenieur civil. Mais qu'est-ce que la durability des infrastructures et, plus important encore, comment peut-elle etre evaluee? Cet article utilise l'infrastructure des egouts pluviaux comme exemple principal pour etudier ces questions, il etudie les problemes des infrastructures d'egouts pluviaux au Canada et examine en detail les methodes devaluation actuelles de la durabilite. Deux series de problemes sont identifiees. La premiere concerne les questions reliees a l'economique, aux institutions, a la croissance de la population, a l'ecologie, ainsi qu'a la sante et securite. La seconde serie examine les incertitudes dans la prevision des impacts reliees aux effets du changement climatique ainsi que les impacts sur la sante des utilisateurs. Les methodes devaluation de la durabilite (classement, indicateurs de durabilite, empreinte, metabolisme, metabolisme etendu, evaluation du cycle de vie), les outils devaluation du rendement, le bulletin de rendement des infrastructures et le protocole du Comite sur la vulnerabilite de l'ingenierie des infrastructures publiques sur Devaluation des changements climatiques sont ensuite examines. Les methodes actuelles devaluation des infrastructures portent principalement sur les aspects fonctionnels du systeme, dont le premier objectif est la reduction de l'utilisation des ressources. Toutefois, elles ne portent pas explicitement sur la resilience et la durabilite a long terme, et ne considerent pas les implications connexes sur la sante ni les capacites de gestion des changements pour la durabilite a long terme. Un nouveau plan d'ensemble serait requis pour evaluer les grandes questions emergentes reliees aux infrastructures. [Traduit par la Redaction] Mots-cles: eau de ruissellement, eau en milieu urbain, infrastructure, changement climatique, evaluation de la durabilite, analyse des ecarts, minimisation des ressources, sante publique, gestion du changement., 1. Introduction The Canadian Society for Civil Engineering (CSCE) in its Vision 2020 statement identified sustainability in infrastructure as a core element for the civil engineering profession. However, what is [...]