| Environnement, ingénierie & développement |  |
N°75 - décembre 2017
1. Éditorial n°75 Déchets Sciences et Techniques
Ce numéro 75 confirme par son contenu la diversité des sujets de recherche développés dans le domaine des déchets et de l’ingénierie environnementale. Depuis la production d’une protéase fongique à partir de déchets agro-industriels à la sélection de sites d’enfouissement de déchets, en passant par des travaux et des réflexions sur le recyclage des DEEE, de poudre de verre, et la comparaison de la performance de foyers de cuisson, chaque lecteur pourra trouver dans ce numéro un thème d’intérêt !Et c’est bien la richesse de notre revue que d’ouvrir les consciences de ses lecteurs et auteurs vers différents horizons qui les sortent de leur domaine de spécialité mais les accompagnent dans un dessein commun : celui de respecter et protéger notre planète pour eux-mêmes et pour les générations futures.Les Objectifs de Développement Durable (ODD) doivent désormais jalonner notre route au quotidien. Ceci afin que les générations futures puissent connaitre des conditions de vie au moins aussi bonnes que les nôtres, mais aussi pour que les populations aujourd’hui les plus défavorisées arrivent, espérons-le, à accéder rapidement à de meilleures conditions de vie sur notre planète si fragile. En cette période de l’année propice aux bonnes résolutions, essayons chaque jour de nous demander ce que nous avons fait dans ce sens, à l’atteinte de quel ODD nous avons contribué. Ainsi, les nombreux petits colibris que nous sommes […]
2. Substitution du ciment CPA par la poudre de verre dans les mortiers à hautes performances
Low ratios water/binder reduce the permeability of the concrete. Moreover, the additions of ends contribute to the improvement of the compactness by their effect on the granular filling. In this research we evaluated the effect of finely crushed glass powder as a cementitious addition (Krati and Kansal, 2016), (Zeghichi et al., 2012) on the physico-mechanical properties of cement-based mortars without addition CEM I (CPA). The cement CPA was substituted by glass powder (GP) with the percentages of 10% and 20% by fixing once the ratio W/C (Water / Cement) and then the ratio W/B (Water / Binder) equal to 0.35, the set of results was compared with the reference mortar without GP. The results obtained show a beneficial behavior of the glass powder on the mechanical characteristics and the durability of the various mortars studied.
3. Modalités de sélection des sites d’enfouissement technique en Algérie et leur prise en charge par les instruments d’aménagement du territoire et d’urbanisme
Landfilling has always been the most common form of treatment in Algeria.The technical nature of this activity has increased considerably since the promulgation of law 01-19-2001 on waste management. Thus, we have passed from the uncontrolled discharge, which is practiced for a long time, to controlled discharge and then to the technical landfill (TL). This latter must allow the final disposal of solid waste in a safe manner, minimizing environmental and public health impacts.The search for suitable sites must not only meet the technical and environmental criteria (waterproofing of the soil and treatment of liquid and gaseous effluents), but also, territorial and urban planning orientations. As a result, territorial and urban planning instruments must provide for a land portfolio for future landfill centers.The aim is to limit the proliferation of uncontrolled dumps and other wild dumps.This work aims first to understand the scope of these instruments and their objectives through a critical reading. Second, to evaluate the management of technical landfill center by these instruments in the case of Algiers agglomeration.
4. Le recyclage est-il l’unique solution pour une gestion durable des DEEE ? Étude de l’incidence du contexte réglementaire et des politiques publiques sur les filières développées en France
20 to 50 million tons of waste electrical and electronic equipment (WEEE) in the world are produced, which could lead risks for the public health and the environment (CNIID and les Amis de la Terre, 2010). One of the peculiarities of the WEEE is their composition at the same time of toxic products and valuable products, in particular precious metals and rare earth. The WEEE requires a particular treatment to avoid the burying. The recycling is a key lever to limit the production of WEEE in the world. It allows the sustainable re-use of present materials in quantity limited on Earth (Grosse, 2010). It has for advantage the capacity to move back of a few years the risk of the end of natural resources, but cannot stop it. It remains necessary to develop other ways in parallel to slow down this problem. The prevention remains a priority for the policy concerning waste. The re-use is a fundamental lever to limit the impacts of the WEEE and the consumption of natural resources. However, in practice the recycling seems to prevail in France and goes away from other recommendations regarding prevention.
5. Analyse des impacts économico-environnementaux du changement d’usage d’un foyer de cuisson traditionnel par un foyer de cuisson amélioré optimisé à charbon de bois dans les ménages de la ville de Kinshasa
This study is oriented to the economic and environmental impacts of the substitution in Kinshasa traditional cookstoves by improved clean cookstoves. We selected two traditional cookstoves (TCS), the TCS D27 and the TCS D23 and two improved cookstoves (ICS), the ICS 16/8/NC and the ICS 16/8/C. The test was carried out under the cooking controlled test (CCT) protocol, which is a laboratory test under strictly controlled conditions. All tests were carried out using the meal much preferred by the average and poor households of Kinshasa. To cook a dry meal of 1150g of beans and 1250g of rice, it takes 2429g of charcoal for a traditional cookstove TCS D27 and 1847g for traditional cookstove TCS D23. However, this only requires 1198g of charcoal for an improved cookstove ICS 16/8/NC and 1081g for an improved clean cookstove ICS 16/8/C. This represents fuel savings ranging from 37% to 55%. A household of 10 people in Kinshasa would spend up to $ 48.61 per month to purchase fuel with a TCS D27 while it will only need $ 22.01 per month for the same culinary tasks using an ICS 16/8/C.
6. Optimisation à l’aide d’un plan d’expériences de la production d’une protéase fongique sur milieu à base de déchets agro-industriels
The production of neutral protease was carried out by the cultivation of Aspergillus oryzae Ahlburg (Cohen) 1042.72 in submerged fermentation using orange waste resulting from juice processing as a basal medium enriched with agro-industrial wastes. Optimization of the enzyme synthesis was achieved using the statistical method of Plackett-Burman design with N = 8 experimentsand N-1 factors; five real (corn-steep liquor, pH, salt, decommissioned dates, whey) and two errors. The results were modeled using a linear regression of the type: β0 + β1X1 + β2X2 + β3X3 + β4X4 + β5X5 + e The statistical results (correlations and significance level) made it possible to select the factors allowing the maximum production of protease (2016 U) obtained on a medium containing orange waste enriched in corn-steep liquor in 72 h and at pH 6. A large production is therefore obtained on a cheap medium.