Can waste foundry sand fully replace structural concrete sand?

Abstract

Foundry sand (FS) waste creates a serious solid waste management problem worldwide due to the high volumes produced, necessitating alternatives to landfilling. A possible route is its use in concrete; however, the current consensus is that FS can only be used for modest sand replacements, based mostly on evidence on concrete with clay-bound FS (greensand). Conversely, this study assessed salient properties of structural concrete with chemically bound FS (polymeric resin binder), for which there is very little information. Concrete mixes were prepared in which FS replaced regular concrete sand partially or fully. The results showed that unlike greensand, the tested chemically bound FS could replace regular concrete sand fully, giving highly workable mixes with good mechanical properties (compressive, splitting and flexural strengths and static modulus of elasticity) similar to those of mixes with regular concrete sand; the effect of FS content on these properties was not statistically significant. Durability in terms of water absorption, carbonation and alkali-silica reaction tests was not adversely affected. The possibility of using high contents of this type of FS in concrete (as opposed to greensand) gives promise for an additional outlet route for large quantities of this waste material with clear economic and environmental benefits.

Performance of Foundry Sand Concrete under Ambient and Elevated Temperatures

“…The already published literature such as Bhardwaj et al [37], Bradshaw et al [38], and Mavroulidou et al [39] and other researchers such as [13,14,15,17,25,26,27] performed many tests on concrete comprising WFS as a partial replacement of sand at ambient temperatures. Since the elevated temperature is a catastrophic phenomenon, the behavior of WFS concrete should be evaluated under elevated temperatures.…”

A Review on the Usage of Recycled Sand in the Construction Industry

“…They stated that up to 60% replacement level of fine aggregates to waste foundry sand, the strength parameters are improved better than that of the conventional geopolymer concrete. Scanning electron microscope (SEM) image of concrete of compressive strength of 46 MPa containing 100% chemically bonded foundry sand (FS), as reported by Mavroulidou and Lawrence [41], is shown in Figure 4.…”

Spent sulfuric acid plant catalyst: valuable resource of vanadium or risky residue? Process comparison for environmental implications

“…Different applications require different chemical compositions and unique properties. However, some common features such as high specific surface area and the presence of an active compound (usually metals, for example Co, Mo, Ni, V, W, Pt, Pd) doped on a support phase (e.g., SiO 2 , Al 2 O 3 , TiO 2 ) (Marafi et al 2017;Cecilia et al 2018). Catalysts have different life cycles (1-2 years for desulfurization, 3-5 years for nitrogen reduction), which can be shortened by factors such as the formation of coke, precipitation of metal salts, or adsorption of organic compounds.…”

“…Two methods that have been considered for this were deoiling or decoking and metal extraction or recovery (Al-Sheeha et al 2013;Wiecka et al 2020). Using unprocessed spent catalysts in the production of new catalysts or using them as additives to other useful materials also has been explored through the years (Furimsky and Biagini 1996;Trochez et al 2015;Marafi et al 2017). However, it is not always possible to remove oil, coke, or metals from the catalyst.…”