Evaluation of the Physico-Mechanical Properties of Concretes Containing Pet and Crushed Sand

The practice of sustainability in construction occupies an increasing prominent position in order to preserve the environment. Considering the environmental impacts caused by waste generation, the use of PET bottle flaks and crushed sand in partial substitution of conventional sand used in concretes is proposed. The aim of this work was to formulate concrete compositions with 1:3 and 1:4 mixtures containing varied water/cement factors and 5, 10, 15 and 20% content of PET wastes and gravel powder. The raw materials were characterized by physico-chemical tests. The formulations were subjected to slump tests and the hardened concrete to absorption, void index and simple compressive strength, with curing of 7 and 28 days, tests. The granulometric analysis allowed the calculation of the fineness modulus, which was 1.50, 3.25 and 0.64 for the crushed sand, gravel and PET respectively. The decrease in the strength with the increase in the PET content in the composite was observed, though, in some mixtures the values indicate the possibility of using this concrete in structural elements.</jats:p

Evaluation of Incorporation of Special Vitreous Residues in Mass for Porcelain Stoneware: Physical and Mechanical Properties

This study aimed to technological alternatives for reuse of vitreous residues from fluorescent lamps, which cause damage to the environment. It was prepared mass to white ceramic with and without lamps residues replacing partially feldspar in proportions of 5% and 10%. Samples were molded and fired at 1000 ° C, 1100 ° C, 1150 ° C, 1200 ° C and 1250 ° C. Physical and mechanical tests were: water absorption, linear shrinkage and rupture by flexural modulus. Samples with 10% of residues reached stability at temperature less than 1250 ° C in all determined properties, confirming the feasibility of these residues in ceramic masses. To optimize the study, it was prepared other samples in proportions of 15% and 20% of waste, at the same level of burning and testing. Results obtained ratified the possibility of using these residues as a flux in ceramic slurries.</jats:p

Catalytic Hydrolysis of Pretreated Sugarcane Bagasse over Acid-Activated Vermiculite Catalysts

Aiming at obtaining glucose, we studied the chemical pretreatment (NaOH + H2SO4) and the hydrolysis of sugarcane bagasse using as catalyst the acid-treated vermiculite clay. Samples of the bagasse before and after the treatment were characterized as to the fiber content and XRD. It has been found that the chemical pretreatment showed satisfactory results providing a decrease of 40% in the lignin content and of 43% in the hemicellulose content, regarding to the bagasse in natura. Catalytic tests in aqueous solution were performed at 200°C, to evaluate the use of vermiculite treated as a catalyst for the hydrolysis of sugarcane bagasse. The reaction product was filtered and the supernatant was analyzed by high performance liquid chromatography. A yield of 6.18% in glucose was achieved.</jats:p

Reuse of Special Glass Waste Like a Flux in Masses for White Ceramics

The accumulation of garbage in urban centers is, undoubtedly, one of the major environmental problems of today. The high costs of implementation and maintenance of collection systems and garbagess treatment, have often,taken to failure of government attempts to resolve this issue.</jats:p

Characterization of Ceramic Composite Waste of Granite, Marble and Caulim for Production of Coating Plates

The mining industry generates large amounts of waste resulting in a very strong environmental impact. Its reuse in ceramic matrix composites are used as coating for floors that have high strength properties with low porosity due to the addition of a structuring polyester resin . This perspective, this work aims at the use of waste generated in the exploration and kaolin processing industries , and solid waste from the cutting of ornamental marble and granite , studying their properties in anticipation of production of coating plates . The residues were benefited by using the process of dry grinding in mill gauges and passed through sieve 0.074 mm ( No. 200 ABNT ) . Were performed on composites testing technology ( water absorption , apparent porosity , bulk density and flexural strength ) and microstructural ( Scanning Electron Microscopy - SEM) . The results showed that the composites showed water absorption ≤ 0.5 having no direct relationship with the porosity , which showed strength within the required standards ( ABNT 13,816 ) for coating plates . Variations in composition ( resin / residue ) showed that composites with higher strength and increased amount of waste resin showed less porous structure , a fact which can be attributed to a better adherence of these residues to the polymer resin and a process of mixing the components more efficient , showing the viability of its production having demonstrated satisfactory properties.</jats:p

Evaluation of the Thermic Behavior of the Coal as a Byproduct through the Low Temperature Conversion Process – LTC of the Sewage Sludge

Brazil follows the global trend to seek viable alternative energy sources that can improve the quality and secure supply of energy with environmental sustainability, allied to the necessity of facilitating a fitting end to the sludge treatment plants sewage. The biomass present in SS is emerging as an alternative to the country's energy matrix, through the Low Temperature Conversion process – LTC of the sludge in the production of biofuel (biooil and coal). This article aims to characterize the coal obtained through the Low Temperature Conversion and evaluate the thermal behavior. In this study physical and chemical studies were made: elemental analysis (CHNO), calorific power, Thermogravimetry (TG) at a heating rate of 10°C min-1 under synthetic air atmosphere, and spectroscopic. The thermogravimetric study found a thermal stability at 300oC. In the spectroscopy in the infrared (IR) regionit was observed bands related to the presence of water, organic matter and silicon oxides in the SS samples analyzed.</jats:p