Contribution à la valorisation de déchets protéiniques et d'emballages plastiques dans une matrice cimentaire. Elaboration et caractérisation de matériaux isolants à Haute Qualité Environnementale

AMIENS-BU Sciences (800212103) / SudocSudocFranceF

Panel and planar experimental shear behavior of wood panels laminated softwood oriented OSB conditioned at different environments

Panel shear strength along the thickness and planar shear along the length of wood panels laminated softwood oriented OSB 10 mm thick, conditioned at different moisture contents (anhydrous medium, ambient temperature and humid medium) was measured on standardized test specimens, cut in half lengthwise panel (L) and half in the perpendicular or transversal direction (T) using two different experimental devices. The measurement results are characterized by a scatter characteristic of these fibrous materials. The cutting direction has little effect on the shear strength which shows an increase with increase in moisture content up to an optimum moisture at ambient temperature to decrease thereafter. Specimens conditioned at ambient moisture showed highest shear strength and moisture saturated specimens are less resistant toward the shear in both cases treated. The ratio between the two is about 2. In addition, the planar shear strength is very large compared to that measured in the case of panel shear for different environments.Keywords : oriented strand board – panel shear strength- planar shear strength - environment – moisture conten

Physical Properties of Composites Manufactured with Two Wastes from Food-Processing Industry

International audienceThe sheer amount of waste being produced nowadays by the food processing industry makes it imperative to identify alternative procedures to recycle them. This paper describes an innovative use of protein waste with consumed plastic bottles within composite materials for building applications. The aim of this study was to investigate this two wastes association on the lightening of the composites. The effect of the protein waste introduction on the physical properties of the concrete manufactured with PET aggregates in the hardened state is studied: total and surface porosity, mechanical strengths, dynamic elasticity modulus and thermal conductivity. The optimal formulation of the basic composite, with PET aggregates, is: S/C = 2.8, W/C = 0.45 and a volume percentage of PET aggregates equal to 35%. The hemoglobin powder was introduced after water in the optimal PET composite. Various H/C mass ratios were used: 0.5, 1 and 2%. The influence of the mixing time after hemoglobin addition was also studied. Relative changes in composites properties due to protein introduction are experimentally investigated. For example a decrease in mechanical strengths and in thermal conductivity was observed. The results obtained allowed the elaborated composites to be functionally classified. So they show that the simultaneous valorization of two kinds of waste of the food process industry may be technically feasible and very interesting for the environment

Partial Discharge in Capacitor Model at Low Temperature

The partial discharge plays an important role in the ageing and the rupture process of solid or mixed insulation systems. Ithas been recognized that the failure of this insulation can be joined to the presence of partial discharge often in inclusionssparkling. Liquid filled cavities can be considered as the most likely defects that can exist in capacitors. In this paper wedescribe the partial discharge evolution at low temperatures in all-PP film capacitors according to the time and the appliedvoltage. We distinguish two regimes of discharges for all the range of temperature and the low temperatures encourage thebreakdown of capacitors at weak voltage, we assign this phenomenon to the increase of the viscosity of filling liquid

Partial discharge in capacitor model at low temperature

International audienc

Electrostatic separation of peeling and gluten from finely ground wheat grains

Sieving and air classification are not efficient enough for the extraction of the high-nutritional-value constituents of wheat. The aim of this article is to validate a simple electrostatic separation method of peeling and gluten, which are two such nutriments contained in finely ground wheat grains. The electrostatic separator is composed of metallic grounded belt conveyer and a rotating roll electrode connected to a high voltage supply. The electrostatic behavior of peeling and gluten powders was characterized using surface potential decay and direct charge measurements. These first set of experiments pointed out the conductive behavior of these powders: in contact with a grounded electrode, they lose their charge in less than 10s. In a second set of experiments, mixtures of 50% peeling and 50% gluten powders were processed by electrostatic separation. Experimental design methodology was used to model the outcome of the separation process as function of two control variables: the high-voltage applied to the roll electrode and the speed of the belt conveyor electrode. In this way, it was possible to determine the optimal operational conditions for the recovery of high-purity peeling and gluten fractions