Papers by Keyword: Residue

Abstract: This paper discusses an environmentally-friendly destination for the residual ashes resulting from the firing of biomass (wood wastes) at the Engie Brasil Cogeneration Power Plant located in Lages, Santa Catarina, Brazil. The study proposes reusing the residue as a substitution for crushed stones in the production of concrete. Environmental, physical, and chemical analyses were performed for characterization of the ashes. Specimens prepared with ash and subjected to testing presented a compressive strength of around 18.63 Mpa (2700 psi), which is in compliance with the ACI-213R and ASTM C330-5 specifications. With pretreatment and proper mixing ratios, biomass ashes may be employed as an aggregate in the manufacture of lightweight structural concrete.

Abstract: EVA (poly (ethylene-co-vinyl acetate)) is a copolymer widely used in the Brazilian footwear industry, where approximately 18% of the EVA remains as waste, principally after the cutting out of insoles. EVA wastes cannot be recycled or reused for the original purpose, but it may be possible to add them to Portland cement to produce concrete for non-structural applications in constructions. This work presents an analytical technique based on the interpretation of X-ray images to assess the spatial distributions of these wastes within concrete test specimens. Evaluation was made of the feasibility of using this technique to study the incorporation of the wastes. Test specimens of concrete were produced according to Brazilian technical standard ABNT-NBR 5738, using a sand/gravel/cement ratio of 3:2:1, where EVA replaced part of the gravel content (10, 20, 50, and 70% of the total gravel volume). Analysis of front projection X-ray images of the specimens showed that the waste was homogeneously incorporated throughout the entire material, as required for concrete. The results of compressive strength tests showed that for samples containing up to 20% of EVA waste, the compression resistance remained almost unchanged, while incorporation of 50 or 70% of waste led to decreases of up to 64% in the resistance.

Abstract: The ceramic industry is one of the most important productive chains of the State of Pará, generating both money and employment. Kaolin has many industrial applications and new uses are constantly surveyed. Although the extraction and processing of kaolin contribute to the economy growth, the activity also provokes serious environmental issues. Being aware of the environmental problem caused by the inadequate decomposition of kaolin residues from the beneficiation process of these minerals, which pollute and attack the environment, this paper aims the chemical, physical and mineralogical characterization of the kaolin residue from the post-treatment disposal provided by CADAM S/A company. The main oxides in the residues were SiO₂ and Al₂O₃. In the X-ray diffraction analysis it was verified that the kaolin residue is basically formed by kaolinite and quartz, in the particle size analysis it was observed that the medium size of the particle was of 1,77 μm.

Abstract: The waste generated in granite processing has caused great social and environmental concern due to the release of its solid effluents into landfills and other places. The recycling and reuse of waste from different industrial processes as new raw materials has been the object of various researches. The use of hydrocyclone in the treatment of residues can represent a very efficient tool for separation and purification of the granite residue. This work aims to characterize and analyse the technological properties of the granite sawdust residues submitted to the hydrocyclone process in comparison with the same residue without going through the hydrocyclone process. The results indicate that the material resulting from this process presented different characteristics from the material without the process, mainly in terms of granulometric distribution and technological properties.

Abstract: The dimension stone industry produces large amount of residue. An alternative to reduce this environmental liability is to apply as glaze in coating ceramic. This research is about the wettability between glaze and red ceramic, applying the sessile drop method. The waste and additives were mixed, pressed, and put over red ceramic plate previously sintered. The system was heated until the melting point of the glaze and the contact angle decreasing was measured in function of the temperature, and in a function of the time at 750 °C and 800 °C. The minimum contact angle value was near 6 ° at 994 °C in the testing changing the temperature, and presents 19 ° and 10 °, respectively, at 750 °C and 800 °C, when the time was varied. The longitudinal section of the samples was analyzed using optical microscopy, showing physical wettability in all testing. This glaze presents good wettability on red ceramic with potential as coating ceramic.

Abstract: Zirconia ceramic stabilized with 3% yttria (3Y - TZP) is the most used ceramic dental materials. During the machining of zirconia blocks in the laboratory to prepare the various types of prostheses, much of the material is lost in powder form, which is subsequently discarded. This study investigates the possibility to recycling of zirconium oxide powder obtained during milling of dental crowns and bridges. Uniaxial and isostatic pressed samples were prepared, sintered and compared to the commercial material. The results indicated that the isostatic pressed samples shows good physical and mechanical properties, comparable to the commercial material, demonstrating the viability to use this recycle material in the same process.

Abstract: The properties of ceramic materials can be greatly influenced when a residue is added to its composition. This article aims to study the incorporation of waste oil well drilling fluid in the standard bulk for fabrication of red ceramic. The success of the merger can reduce costs in the production of ceramic pieces and reduce the environmental impacts caused by waste. The results reveals that the use of the residue for the manufacture of the ceramic products is possible (tiles, massive bricks and hollow bricks) replacing clay up to 40%, according the requirements of the norm and in the literature for the technological properties of the final product.

Abstract: Hydrocracking of Venezuelan heavy oil with no catalyst, dispersed Mo catalyst and Mo/Al₂O₃ catalyst were carried out to investigate the effect of Mo/Al₂O₃ catalyst component on the composition of residue hydrocracked product. Experimental data revealed that both dispersed Mo catalyst and Mo/Al₂O₃ catalyst improved the conversion of Venezuelan heavy oil and inhibited the formation of coke, but the two types of catalyst have the opposite effects on generation of light products. Besides, the activity metal suppressed the formation of isomerization product while the acidity support enhanced it.

Abstract: Thousands of tons of tar residue are gained as by-products in the production of toluene diisocyanate (TDI) using heavy solvent. It is very necessary to recycle the residue. In view of residue composition’s diversity, high purity isophthalic acid (IPA) was obtained as product by hydrolysis of diethyl isophthalate (DEIP) in the residue. Multiple factors which affected the yield of isophthalic acid were investigated. Suitable reaction conditions for industrial production were summarized: the tar residue was grinded to 100 mesh, mass ratio (NaOH: material) was 0.3:1, react in water for 3 hours at 90°C.

Abstract: In this paper, wollastonite nanopowder were successfully synthesized by the surfactants modified-calcined method using calcium silicate residue of potassium feldspar after extraction of potassium and alumina. The effects of modifier and calcined temperature on the phase composition, morphology and microstructure were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the phase of samples with different modifier processing is wollastonite-2M, while CTAB as modifier can avoid preferred orientation growth. The obtained wollastonite powder is spherical in morphology and well dispersed with the particle size of approximately 150nm.