Stabilization/solidification of mercury-contaminated waste ash using calcium sodium phosphate (CNP) and magnesium potassium

作者：Cho Jae Han; Eom Yujin; Lee Tai Gyu^*

来源：Journal of Hazardous Materials, 2014, 278: 474-482.

DOI：10.1016/j.jhazmat.2014.06.026

• Mercury
• CBPC
• Calcium sodium phosphate
• TCLP
• Compressive strength

This study examined the stabilization and solidification (S/S) of mercury (Hg)-contaminated waste ash generated from an industrial waste incinerator using chemically bonded phosphate ceramic (CBPC) technology. A magnesium potassium phosphate (MKP; MgKPO4 center dot 6H(2)O) ceramic, fabricated from MgO and KH2PO4, and a calcium sodium phosphate (CNP; CaNaPO4) ceramic, fabricated from CaO and Na2HPO4, were used as solidification binders in the CBPC process, and Na2S or FeS was added to each solidification binder to stabilize the Hg-contaminated waste ash. The S/S processes were conducted under various operating conditions (based on the solidification binder and stabilization reagent, stabilization reagent dosage, and waste loading ratio), and the performance characteristics of the S/S sample under each operating condition were compared, including the Hg leaching value and compressive strength. The Hg leaching value of untreated Hg-contaminated waste ash was 231.3 mu g/L, whereas the S/S samples treated using the MKP and CNP processes exhibited Hg leaching values below the universal treatment standard (UTS) limit (25 mu g/L). Although the compressive strengths of the S/S samples decreased as the sulfide dosage and waste loading ratio were increased, most of the S/S samples fabricated by the MKP and CNP processes exhibited good mechanical properties.

• 出版日期2014-8-15