Solidification–stabilization of organic and inorganic contaminants using portland cement: a literature review

Abstract

The treatment of hazardous wastes using cement-based solidification–stabilization (S–S) is of increasing importance as an option for remediating contaminated sites. Indeed, among the various treatment techniques, S–S is one of the most widely used methods for treating inorganic wastes. To enhance the application of S–S and to further develop this technology for site remediation, particularly for organic contaminants, it is important to have a better understanding of the mechanisms involved in the process. The primary objective of this review is to survey the current knowledge in this subject, focusing on (i) cement chemistry, (ii) the effects of inorganic (heavy metals) and organic compounds on cement hydration, and (iii) the mechanisms of immobilization of different organic and inorganic compounds. For heavy metals, cement-based S–S technology has been shown to be effective in immobilizing the contaminants, even without any additives. In applying cement-based S–S for treating organic contaminants, the use of adsorbents such as organophilic clay and activated carbon, either as a pretreatment or as additives in the cement mix, can improve contaminant immobilization in the solidified–stabilized wastes. The concept of degradative solidification–stabilization, which combines chemical degradation with conventional solidification–stabilization, seems promising, although further study is required to assess its technical and economic feasibility.Key words: cement, contaminated soil, immobilization, organics, precipitation, adsorption.

Mechanical and Leaching Behavior of a Stabilized and Solidified Anthracene-Contaminated Soil

“…Portland cement is commonly utilized as binder in S-S remediation (Liu et al, 2012 andParia andYuetl, 2006). By using cement, heavy metals are converted to stable forms and are entrapped in the solid cementation matrix of the stabilized contaminant soil (Paria and Yuetl, 2006).…”

“…By using cement, heavy metals are converted to stable forms and are entrapped in the solid cementation matrix of the stabilized contaminant soil (Paria and Yuetl, 2006). Strength, permeability and leaching properties of S-S treated soils have been extensively studied by Yilmaz et al (2003), Antemir et al (2010), Kogbara and AlTabbaa (2011) and Du et al (2012) among others.…”

Assessment of the operating windows of a combined solidification/stabilization and granulation treatment applied to industrial soil in the context of brownfield regeneration

“…Similarly to Ba, the increase of Mo leaching, of up to 42% of that of the as received material for the crushed pellets, was ascribed to the effect of the cement, which leached Mo in notable concentrations, even higher than the limit imposed for disposal in inert waste landfills. Furthermore, the treatment appeared to exert a mobilizing effect also for Cr and Cu, which, besides the addition of the cement, was correlated to the increase in eluate pH, which may have led to the formation of more soluble phases containing these metals, such as hydroxides [13]. Moreover, Cu leaching concentrations were found to be comparable to those observed for the eluates of the untreated industrial soil and in both cases they proved higher than the limits established for the reuse of waste materials in simplified procedure (Italian Ministerial Decree 186/06).…”

Comparison of mechanical and leaching behaviours of pulverised fuel ash/low-grade magnesium oxide-cement blended stabilised/solidified baghouse dust

“…The right choice and effective use of binders in S/S is important since they physically and chemically trap contaminants. Portland cement and lime have been widely used as primary binders while ground granulated blast furnace slag (GGBS), pulverised fuel ash (PFA), natural pozzolans, low grade magnesium oxide and silica fume are widely used as secondary binders (Alsheyab & Khedaywi, 2013;Arribas, Santamaría, Ruiz, Ortega-López, & Manso, 2015;Chang, Lin, Ko, & Liaw,1999;Chen, Tyrer, Hills, Yang, & Carey, 2009;del Valle-Zermeño, Giro-Paloma, Formosa, & Chimenos, 2015;Fernandez, Macias, Guerreo, Lorenzo, & Goni, 2000;Gervais & Ouki, 2000, 2002, Lampris, Stegemann, & Cheeseman, 2008, 2009a, 2009bParia & Yuet, 2006;Pasetto & Baldo, 2010;Poon, Lio, & Tang, 2001; Rodrfguez-Piñero, Pereira, de Elvira Francoy, & Vale Parapar, 1998;Salihoglu & Pinarli, 2008;Serjun et al, 2015;Shi & Spence, 2004;Stegemann & Zhou, 2009).…”