Abstract

The proposal of this work is to study materials, which initially were classified as disposable, in building construction as new alternative materials. In this way, this research studied the partial replacement of Portland cement in mortars by the following pozzolans: sugar cane bagasse ash (SCBA), rice husk ash (RHA), metakaolin (MK) and silica fume (SA). Theses composites were compared with a control mixture, which no Portland cement replacement, in the following tests: compressive strength, consistency, water capillarity and water immersion.   The replacements percentages carried out were 5, 10, 15, 20, 25 and 30% for SCBA, RHA and metakaolin, and 5, 10 and 15% for silica fume by weight. The compressive strength test was performed at curing times of 3, 7, 28 and 90 days, whereas water capillarity and water immersion were carried out at 28 days. In the early ages, few mixtures showed resistance above the reference, but with 90 days, six mixtures passed the control. All mixtures with pozzolans presented less water absorption by immersion and capillarity. Sustainably, the use of SCBA, RHA, MK and SA is viable.

Abstract

Greater focus on sustainability across numerous industries has led to an uptick in the demand for increasingly environmentally-friendly materials. Biochar has recently come into the arena as a material that is created from biomass that has undergone pyrolysis. The benefits of this material include inputs easily found in nature (ie. pine wood), high biodegradability, and high relative strength. When combined with epoxy resin, it was hypothesized that this composite would create a stronger, more environmentally-friendly material than either component by itself. Through the use of ABAQUS, a finite element analysis software, representative volume elements (RVEs) were created in order to test several configurations, load magnitudes & types, variations of biochar, and mass percentages to determine the most stress-resistant material. Through analysis of the maximum and minimum von Mises Stress percentages experienced by each RVE, 4 assignable sections of spruce-fir and pine sawdust biochar collectively produced the smallest von Mises Stress percentages, indicating a low likelihood of plastic characteristics after applied stress. Across all RVEs, the median number of assignable sections (4) for biochar had the lowest von Mises Stress percentages, indicating that maintaining elastic properties is best done through a hybrid of epoxy resin and biochar. In terms of the best type of stress, hydrostatic stress gave more favorable results (decreased von Mises percentages). Differences between the reaction force from varying pressures was proportional, indicating similar behavior at different stress values. Future applications include interdisciplinary applications of epoxy resin in green-transportation, green-construction, or crack prevention across other environmentally conscious disciplines.

Abstract

This study aimed to determine the feasibility of using the residue from the burning of eucalyptus wood (RBE), resulting from energy generation in industrial furnaces, as solid biofuel (briquettes) for sustainable and economically viable energy generation. For this, the physicochemical characterizations of this material were made by X-ray fluorescence (XRF), X-ray diffraction (XRD) and thermogravimetry (TG/DTG), as well as the ash superior calorific power (SCP) was determined. The physico-chemical analyzes indicated that although the chemical composition of the ash is mostly composed of calcium carbonate, a considerable amount of residual organic matter can be found, on average 7.18%. The superior calorific power value obtained for the ash was 19.73 MJ/Kg. When molded into briquettes, the ash was subjected to the ignition process and the combustion process was maintained naturally during the total burning of the solid, indicating the viability of the system.