Assessment of industrial wastes in mortar layers deposited on stainless steel sheets of sinks

Abstract

Metal sinks are broadly produced with stainless steel sheets. These steel sheets are thin and may easily bend under mechanical forces. Wood or a mortar layer is used to strengthen the steel sink. In the last decade mortars have been used to replace wood. The mortar mixture is poured on the backside of the metal sink. After setting and hardening, the mortar prevents the sink metal sheet from bending.Since the concern with the cost of raw materials and with the environment, some industries are trying to use industrial waste as raw materials in mortar production. Actually, one of the biggest challenges the mankind needs to face nowadays is how to assure a continuous industrial development and improve the environment. This issue has been discussed in many global summits around the world in order to reduce the amount of industrial wastes. For the time being, political leaders have failed in find an appropriate compromise between industrial development and environmental protection. Despite all the discussion about sustainable development there is a lack of political will to create new regulations about reasonable use of raw materials, recycling and reutilization of wastes. Most of the countries have tough environmental protection laws so that the factories are supposed to adopt suitable treatment and disposal procedures for their industrial wastes. Nevertheless, AbstractThis work deals with the properties of alternative mortars destined to strengthen metal sheets of sinks. The performance of these mortars was compared to that of a basic mortar made of cement, sand, and water, named standard mortar (SM). One of these mortars, named alternative mortar 2 (AM2), and composed of cement, textile residue, polyurethane, polypropylene fibers and water, was developed recently to replace the current one, named alternative mortar 1 (AM1), composed of cement, sand, polystyrene, polypropylene fibers and water. These mortars were manufactured and aged in a room in atmospheric environment for 7, 14, 28, 60 and 90 days, either with or without initial drying in a furnace. After cure of 90 days the flexion strength stress of the SM, AM1 and AM2 mortars was 5.21, 3.84, and 1.42 MPa, respectively. The SM and AM1 mortars were constituted of C-S-H phases, Ca(OH) 2 , SiO 2 , AFm and AFt (monossulphate/ ettringite) phases. The AM2 mortar presented, apart from the compounds mentioned above, CaCO 3 . This compound is from the textile residue that is composed essentially of CaCO 3 and Ca(OH) 2 . The reduction in flexion strength of AM1 mortar, compared to SM mortar, is caused by the polystyrene whereas the lowering mechanical strength of the AM2 is due to both polyurethane and textile residue. Even so, its mechanical strength is acceptable because the flexion strength stress required for the industrial application is 1.0 MPa. Keywords: mortar, industrial waste, sink, stainless steel. Resumo O objetivo desse trabalho foi estudar as propriedades de argamassas alternativas usadas para reforço de chapas metálicas de pias de cozinha. O desempenho de...

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