Building activity is currently demanding noticeable amounts of natural inert materials, such as gravel and sand, usually provided by natural sediments. The extraction of sediments can modify river-profiles and their equilibrium as well as quarrying activities could induce environmental problems. The use of recycled aggregates is promoted by the EU which has provided guidelines for common strategies for a correct re-use of construction and demolition (C&D as proposed by Poon et al., 2001) (DG ENV. E. 3, 2000). As for the Italian situation, currently the legislation (D.L. 152/06) is encouraging the re-use of C&D inert materials but the re-utilisation of these materials is hampered by the scarcity of suitable plants for processing, as a result this resource is used as a lower quality materials for low grade application (i.e. road sub-base). In this study, different grain-size fractions, obtained by a grain-size sorting, from a C&D processing plant in Rovigo (NE Italy), were investigated through X-ray fluorescence (XRF) and X-ray diffractometry (XRD) analyses, in order to evaluate their chemical and mineralogical composition, assisting in the development of improved recycling methodologies. The results indicate that, through an opportune crushing and sorting operation for C&D material, it is possible to obtain grain-size fractions with roughly homogenous chemical and mineralogical composition on each fraction. The homogeneity of the materials can be considerably improved if a careful differentiation takes place during the initial stages of C&D production (Poon, 1997; Poon et al. 2001). The finer fractions could be used for hydraulic mortar preparation only if the fraction of bricks, tiles and terracotta is prevalent, providing material with pozzolanic attitude (Baronio et al., 1997; Corinaldesi et al., 2002; Zendri et al., 2004). These fine recycled fractions were used in high grade application as starting materials for ceramics, requiring industrial treatment such as sintering process, Preliminary results have shown that there is a real possibility to use this materials for preparing suitable ceramic mixing. Next step testing will be testing for using the coarse fractions as aggregates for preparing concrete.
Chemical-mineralogical characterisation of construction and demolition waste and hypothesis for their reuse
TOFFANO, Alice;MARROCCHINO, Elena;VACCARO, Carmela
2008
Abstract
Building activity is currently demanding noticeable amounts of natural inert materials, such as gravel and sand, usually provided by natural sediments. The extraction of sediments can modify river-profiles and their equilibrium as well as quarrying activities could induce environmental problems. The use of recycled aggregates is promoted by the EU which has provided guidelines for common strategies for a correct re-use of construction and demolition (C&D as proposed by Poon et al., 2001) (DG ENV. E. 3, 2000). As for the Italian situation, currently the legislation (D.L. 152/06) is encouraging the re-use of C&D inert materials but the re-utilisation of these materials is hampered by the scarcity of suitable plants for processing, as a result this resource is used as a lower quality materials for low grade application (i.e. road sub-base). In this study, different grain-size fractions, obtained by a grain-size sorting, from a C&D processing plant in Rovigo (NE Italy), were investigated through X-ray fluorescence (XRF) and X-ray diffractometry (XRD) analyses, in order to evaluate their chemical and mineralogical composition, assisting in the development of improved recycling methodologies. The results indicate that, through an opportune crushing and sorting operation for C&D material, it is possible to obtain grain-size fractions with roughly homogenous chemical and mineralogical composition on each fraction. The homogeneity of the materials can be considerably improved if a careful differentiation takes place during the initial stages of C&D production (Poon, 1997; Poon et al. 2001). The finer fractions could be used for hydraulic mortar preparation only if the fraction of bricks, tiles and terracotta is prevalent, providing material with pozzolanic attitude (Baronio et al., 1997; Corinaldesi et al., 2002; Zendri et al., 2004). These fine recycled fractions were used in high grade application as starting materials for ceramics, requiring industrial treatment such as sintering process, Preliminary results have shown that there is a real possibility to use this materials for preparing suitable ceramic mixing. Next step testing will be testing for using the coarse fractions as aggregates for preparing concrete.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
