Characterization of a mortar made with cement and slag vitrified from a MSWI ash-mix and CMP sludge

• Published in: Construction & building materials Vol. 38; pp. 22 - 30
• Main Authors: Shih, Ping-Yu, Lee, Po-Hua, Nian, Kai-Jie, Lee, Tzen-Chin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2013; Elsevier B.V
• Subjects: Analysis; Chemical mechanical polishing sludge; Compressive strength; Fly ash; Incinerators; MSWI fly-ash; Nano-particles; Slag–cement mortar; Thermal properties; United States; Slag–cement mortar; Chemical mechanical polishing sludge; Compressive strength; Nano-particles; MSWI fly-ash
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2012.07.083

► MSWI fly- and scrubber-ash and CMP sludge can be transformed into useful materials. ► MSWI ash-mix and CMP sludge were melted to form a non-toxic slag. ► The strength of the slag-blended cement mortar (SBCM) is superior to OPCM specimens. ► The test results overcame the weaker early strength of SBCM in current studies. ► SBCM exhibits the greater strength by nano-particle effect and Pozzolanic reaction. Fly- and scrubber-ash from a municipal solid waste incinerator (MSWI) were mixed uniformly according to their production weight proportions, and the resulting mixture was added to the half weight of the chemical mechanical polishing (CMP) sludge that was further melted to form a slag. The slag-blended cement mortar (SBCM) specimens were manufactured with 5, 10, 20 and 30wt.% cement replaced by slag powder, and the molded specimens were evaluated for their compressive strength. The test results revealed the compressive strengths of the SBCM specimens with 5, 10, and 20wt.% cement replacement were higher than those of ordinary Portland cement mortar (OPCM) specimens at all curing ages (1–90days). The test results exhibited good strength evolution and the stronger strength at early age is shown in the test, comparing with those of the studies using the mix with slag-only. This study also investigated the toxicity characteristic leaching procedure (TCLP) test. The test results indicate that the amount of leached heavy metals was far below the EPA’S regulatory threshold. Thus, the MSWI ash-mix and CMP sludge can potentially be recycled as resources.