Separability studies of construction and demolition waste recycled sand

Autor(es)

Ulsen, Carina ^[1] ; Kahn, Henrique ^[1] ; Hawlitschek, Gustav ^[1] ; Masini, Eldon A. ^[1] ; Angulo, Sergio C. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Engn, Min & Petr Dept, BR-05508030 Sao Paulo - Brazil

^[2] Inst Technol Res Sao Paulo, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: WASTE MANAGEMENT; v. 33, n. 3, p. 656-662, MAR 2013.
• Citações Web of Science: 20

Resumo

The quality of recycled aggregates from construction and demolition waste (CDW) is strictly related to the content of porous and low strength phases, and specifically to the patches of cement that remain attached to the surface of natural aggregates. This phase increases water absorption and compromises the consistency and strength of concrete made from recycled aggregates. Mineral processing has been applied to CDW recycling to remove the patches of adhered cement paste on coarse recycled aggregates. The recycled fine fraction is usually disregarded due to its high content of porous phases despite representing around 50% of the total waste. This paper focus on laboratory mineral separability studies for removing particles with a high content of cement paste from natural fine aggregate particles (quartz/feldspars). The procedure achieved processing of COW by tertiary impact crushing to produce sand, followed by sieving and density and magnetic separability studies. The attained results confirmed that both methods were effective in reducing cement paste content and producing significant mass recovery (80% for density concentration and 60% for magnetic separation). The production of recycled sand contributes to the sustainability of the construction environment by reducing both the consumption of raw materials and disposal of COW, particularly in large Brazilian centers with a low quantity of sand and increasing costs of this material due to long transportation distances. (C) 2012 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 10/15543-1 - Caracterização de agregados miúdos de alta qualidade produzidos a partir de resíduos de construção e demolição
• Beneficiário: Henrique Kahn
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 09/54007-0 - EMU: aquisição de equipamentos complementares e de apoio para facility de microscopia eletrônica de varredura
• Beneficiário: Henrique Kahn
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários