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France is Europe's leading producer of flaxseed. This seed is rich in omega-3, energy, and protein for animals, but it also contains anti-nutritional factors such as mucilage. Thus, mucilage must be removed and could be used as a bio-admixture in cementitious materials development, reducing the environmental impact of cementitious materials. This study aims to valorize the usage of flaxseed mucilage (FM) in ordinary Portland cement. FM caused macroscopic and microscopic changes in the materials studied. The higher the concentration, the greater the changes were. The admixed samples showed an exponentially concentration-dependent delay in setting. FM degradation products induced by the cementitious conditions accentuated the delay. However, this delay in setting did not affect the hydrates' growth in the material. In fact, FM showed a "delay accelerator" behavior, meaning that once hydration began, it was accelerated as compared to a reference. Macroscopically, FM induced significant flocculation, increasing material porosity and carbonation. Consequently, bulk density and thermal conductivity were reduced. At the highest amount of FM admixture (0.75% w/w), FM allowed bridge formation between Ca(OH)2 crystals, which can improve the mechanical properties of mortars. Because FM is highly hygroscopic, it has the capability to absorb water and subsequently release it gradually and under controlled conditions into the cement matrix. Therefore, regulation of water diffusion from the mucilage may induce the self-healing properties responsible for mechanical properties similar to that of the reference in the medium to long term. [ABSTRACT FROM AUTHOR]

The development of new lightweight concrete based on the valorization of local materials and waste in construction is an environmental and sustainable approach. In this context, the studied composite is a sand concrete (dune and alluvial) lightened by wood shavings to improve its thermophysical properties. The objective is to investigate the orientation effect of an outside wall made with this material in an arid environment on the thermophysical properties of the wall, namely the time lag (Φ) and the decrement factor (f). The experimental study has been dedicated, first of all, to determine the optimal composition of sand concrete lightened by wood shavings, which the content is 60 kg/m3. This composition is a compromise between studied compactness and workability. Then, to study the thermal properties of the sand concrete without wood shavings (SC-W-WS) and sand concrete lightened by wood shavings (SC-WS). Finally, a numerical simulation using the EnergyPlus software was made to study the wall orientation effect designed in the Laghouat city (south of Algeria). The results obtained show that the substitution of sand by wood shavings has improved thermal properties of the wood sand concrete namely: the thermal conductivity, the specific heat and the thermal diffusivity. The simulation results are very interesting, because all orientations are right for the sand concrete lightened by wood shavings (SC-WS). Nevertheless, the north and the west orientations are wrong in the case of the sand concrete (SC-W-WS). However, the east orientation has the longest time lag, which is consistent with the literature. The advantage of these results is in favour of concrete having improved thermophysical properties.

The lubricating oil industry is widespread in the world, but getting rid of the used oils has become an environmental concern. Lubricating oils are used in industries and cars but potentially contaminate groundwater after use. This research uses montmorillonite clay to refine old oil treated with acetic acid. Compared to more conventional procedures, the suggested strategy for treating waste oil is more cost-effective due to the relatively inexpensive cost of the acid and the modest process conditions. Water content, sediment content, density, flash and fire points, viscosity, viscosity index, total acid and base number, pour points, and refractive index were among the physicochemical parameters of the treated oil that were examined as a result of this treatment. We analyzed the oils using Fourier transform infrared spectroscopy (FTIR) and atomic absorption spectrometry (AAS). New oil (10w 40), old oil, oil treated with acetic acid, and montmorillonite clay were all put through their paces in a battery of tests. The therapy's physical and chemical alterations were examined across all fields. The findings demonstrated the efficiency of montmorillonite clay due to the strength of the acid to separate the sludge and the lack of compounds hazardous to the environment. The process described here enables recycled oil to be reclaimed as base oil. [ABSTRACT FROM AUTHOR]