Leaching behaviour of elements and evaluation of pre-treatment methods for municipal solid waste incinerator residues in column leaching tests

Abstract

Two new pre-treatment methods (water-washing/carbonation and carbonation/phosphate stabilization) of municipal solid waste (MSW) incinerator residues were evaluated by column leaching tests under aerobic conditions and anaerobic conditions (which were changed to aerobic conditions after 10 months). A mixture of bottom ash and fly ash (5: 1 ratio) was pre-treated using each method. Shredded incombustible residues (SIR) were added to each ash preparation in proportions similar to the ratios present in landfills. For comparison, landfill wastes typical of Japan, namely, a mixture of bottom ash, chelating-pre-treated fly ash, and SIR, were also examined. Leachate samples were collected periodically and analysed over a 15-month period. When compared with chelating pre-treatment, both water-washing/carbonation and carbonation/phosphate stabilization reduced the leaching of Pb, Al, and Cu by about one to two orders of magnitude. Moreover, the initial concentrations of Ca and Pb in leachates from column of water-washing/carbonation were 56-57% and 84-96% less than those from the column of carbonation/phosphate stabilization. Therefore, water-washing/carbonation was considered to be a promising approach to obtain early waste stabilization and to reduce the release of heavy metals to near-negligible levels. The leaching behaviour of elements was also discussed.

Keywords

Municipal solid waste incinerator residues pre-treatment water washing carbonation phosphate stabilization heavy metals column leaching tests leaching behaviour wmr 661-8

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References

Allison, J.D. , Brown, D.S. , & Novo-Gradac, K.J. (1991) MINTEQA2/PRODEFA2, A Geochemical Assessment Model for Environmental Systems: Version 3.0 User’s Manual. Environmental Research Laboratory, U.S.EPA: Athens, GA .

Cernuschi, S. , Giugliano, M. , & De Poli, I. (1990) Leaching of residues from MSW incineration . Waste Management & Research, 8, 419-427 .

Environment Agency, Japan . (1973) Testing Methods for Metals in Industrial Wastes. Notification No. 13 of the Environment Agency, February 17, 1973, in Japanese .

Fruchter, J.S. , Rai, D. , & Zachara, J.M. (1990) Identification of solubility-controlling solid phases in a large fly ash field lysimeter . Environmental Science & Technology, 24, 1173-1179 .

Johnson, C.A. & Furrer, G. (2002) Influence of biodegradation processes on the duration of CaCO3 as a pH buffer in municipal solid waste incinerator bottom ash . Environmental Science & Technology, 36, 215-220 .

JSAC (1994) Water Analysis 4th edition., The Japan Society for Analytical Chemistry, Hokkaido branch, Japan (in Japanese).

Kamiishi, H. & Takahashi, T. (1998) Stabilisation of chelating-pre-treated fly ash (in Japanese) . Proc. 9th Annual Conference of the Japan Society of Waste Management Experts, Nagoya, Japan, pp. 791-793 .

Kim, S.Y. , Matsuto, T. , & Tanaka, N (2002) Solubility and adsorption characteristics of Pb in leachate from MSW incinerator bottom ash . Waste Management & Research, 20, 373-381 .

Kim, S.Y. , Matsuto, T. , & Tanaka, N (2003) Evaluation of pre-treatment methods for landfill disposal of residues from municipal solid waste incineration . Waste Management & Research, 21, 416-423 .

10.

Meima, J.A. & Comans, R.N.J. (1997) Geochemical modelling of weathering reaction in municipal solid waste incinerator bottom ash . Environmental Science and Technology, 31, 1269-1276 .

11.

Ministry of the Environment, Japanese White Paper on the Environment, 2003.

12.

Noma, Y. , Kita, A. , Takanobe, K. , & Kodama, M. (1989) Long term stability of EP fly ash with chelating agent (in Japanese) . Proc. 1st Annual Conference of the Japan Society of Waste Management Experts, Tokyo, Japan, pp. 173-176 .

13.

Sakanakura, H. (1999) Study on stabilisation of heavy metal in municipal solid waste incinerator residues by chelating agents (in Japanese). PhD thesis, Hokkaido University, Sapporo, Japan, pp 2 and 45-48

14.

Tanaka, N. (2000) Construction and Management of MSW Landfill, 1st edition, pp. 137-138. Gihoudo Publications, Japan .

15.

Tanaka, Y. (1995) Recent performance on the treatment of heavy metals by chelating methods (in Japanese) . Sangyo to Kankyo 24, 77-79 .

16.

Yuki, O. , Kawaguchi, S. , Ohno, K. , Moriyama, N. , & Urushiyama, E. (1997) Long term stability of chelating-pre-treated fly ash in column leaching tests (in Japanese) . Journal of Japan Waste Management Association, 50, 134-137 .