Behavior of stabilized fly ashes in solid waste landfills

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

DOI:https://doi.org/10.1016/S0956-053X(96)00096-7· OSTI ID:544185

Shimaoka, Takayuki; Hanashima, Masataka ^[1]

---

1. Fukuoka Univ. (Japan). Dept. of Civil Engineering

In Japan, the fly ash generated by incineration of municipal solid waste has come to be handled as general waste under special management in recent years. At the same time, direct landfilling or ocean dumping of fly ash is legally prohibited. To avoid the possibility of causing damages affecting human health or life environment, fly ash must be subjected to intermediate treatment, and must be stabilized, encapsulated and made hygienic by removing pollutants. Four methods can be given for fly ash intermediate treatment: (1) cement solidification, (2) treatment by chemicals, (3) acid and other solvents and (4) melting and solidification. On the other hand, various phenomena affecting fly ash occur on the landfilled waste layer, such as generation of organic acid and carbon dioxide gas due to decomposition of solid waste. Fly ash solidified by cement is deteriorated by water-soluble sulfate and organic acid and carbon dioxide gas produced by decomposition of organic substances in the municipal solid waste. This may result in a reduced strength of hazardous substances and re-melting of fly ash solidified by cement. Furthermore, encapsulated hazardous heavy metals may be eluted from fly ash treated by chemicals due to the change in chemical environments in the landfilled solid waste layer according to stabilization of the landfilled solid waste. In this present study, the large-sized landfill model lysimeter is filled with cement-solidified fly ash or chemically treated fly ash treated together with municipal solid waste to obtain correct information on the changes in the physical and chemical properties of the cement-solidified fly ash, and temporal concentration of hazardous substances contained in seepage leachate or leachate in the landfilled solid waste layer, thereby clarifying the long-term stability of the disposed fly ash.

• OSTI ID: 544185
• Journal Information: Waste Management, Journal Name: Waste Management Journal Issue: 5-6 Vol. 16; ISSN WAMAE2; ISSN 0956-053X
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
54 ENVIRONMENTAL SCIENCES
CHEMICAL COMPOSITION
CHEMICAL PROPERTIES
FLY ASH
JAPAN
MUNICIPAL WASTES
PHYSICAL PROPERTIES
SANITARY LANDFILLS
SOLID WASTES
STABILIZATION
WASTE PROCESSING