Utilizing coal fly ash as a landfill barrier material

Journal Article · Tue Dec 31 04:00:00 EST 1996 · Waste Management

DOI:https://doi.org/10.1016/S0956-053X(96)00108-0· OSTI ID:544129

Nhan, C T; Graydon, J W; Kirk, D W ^[1]

---

1. Univ. of Toronto, Ontario (Canada). Dept. of Chemical Engineering and Applied Chemistry

The chemical barrier properties of a composite of coal fly ash, lime dust and bentonite were studied as a potential barrier material for a landfill. An experimental study was performed to measure the hydraulic and chemical barrier properties of the material using both water and a synthetic municipal solid waste (MSW) leachate. The composite material was found to have a hydraulic conductivity of 4.3 {+-} 1.6 {times} 10{sup {minus}8} m/s with water. More importantly, the composite material had chemical barrier properties for metal ions in the leachate liquid. Results show that the principal retarding mechanism for the heavy metal ions was precipitation. In accelerated tests, for the metal ions studied, the retardation order was Pb > Zn > Fe. The migrating front of the heavy metals (Fe, Zn and Pb) under landfill conditions is estimated to be less than 0.10 m in 15 years assuming a constant pH of 6. The coal fly ash barrier appears to be an effective chemical barrier for MSW landfill leachate.

• OSTI ID: 544129
• Journal Information: Waste Management, Journal Name: Waste Management Journal Issue: 7 Vol. 16; ISSN WAMAE2; ISSN 0956-053X
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
CHEMICAL PROPERTIES
FLY ASH
LEACHING
LINERS
SANITARY LANDFILLS
WASTE MANAGEMENT
WASTE PRODUCT UTILIZATION