Model simulations for describing water transport in a landfill with bottom ash from a municipal solid waste incinerator (MSWI): model validation and scenarios

Abstract

In the present study the water movement in a bottom ash landfill from a municipal solid waste incinerator (MSWI) was investigated. The pore regime of such landfills consists of macropores (with diameter > 50 [.mu]m), which make up about two-thirds of the total porosity and micropores. The program MACRO, which describes flow through porous media and takes both macro- and micropore flows into account, was applied. The model was calibrated with a time series from the landfill Riet, near Winterthur in Switzerland. In the present study the model was recalibrated at a time series for 1 year. With this scenario the influence of an expected reduction or increase of the porosity on leachate behaviour of such landfills over a long time (> 100 years) was studied (‘long-term behaviour’). It has been shown that reliable information about water percolation can only be provided by obtaining more information about the hydraulic structure of such landfills. In particular, the number of macropores and the porosity exert great influence on the water movement.

Keywords

Bottom ash landfill hydraulic structure micro- and macropores porosity validation scenarios simulation percolation water movement wmr 645-1

References

Beven, K. & Germann, P. (1981): Water flow in soil macropores. A combined flow model . Journal of Soil Science, 32, 15-29 .

Brooks, R.H. & Corey, A.T. (1964): Hydraulic Properties of Porous Media. Hydrology paper Nr. 3; Colorado State University, Fort Collins, Colorado .

Darcy, H. (1856): Les fontaines publiques de la ville de Dijon. Dalmont, Paris.

Gerke, H.H. & van Genuchten, M.T. (1993): A dual-porosity model for simulating the preferential movement of water and solutes in structured porous media . Water Resources Research 29(2), 305-319 .

Hartmann, F. (2000): Modellrechnungen zur Beschreibung der Wasserbewegung durch eine Müllschlackendeponie unter besonderer Berücksichtigung der Porenstruktur. Dissertation Nr. 13732 ETH Zürich/EAWAG Dübendorf.

Hartmann, F. , Bader, H.-P. , Scheidegger, R. , & Baccini, P. (2001): Water transport in a bottom ash landfill from a Municipial Solid Waste (“MSW”) incinerator . The Journal of Solid Waste Technology and Management, 27(2), 76-81 .

Jarvis, N.J. & Larsson, M. (1998): The MACRO Model (Version 4.1)-Technical Description. Swedish University of Agricultural Sciences, Department of Soil Sciences, Uppsala, Sweden .

Johnson, C. A. , Richner, G. A. , Vitvar, T. , Schittli, N. , & Eberhard, M. (1998): Hydrological and geochemical factors affecting leachate composition in municipal solid waste incinerator bottom ash. Part I: the hydrology of landfill Lostorf, Switzerland . Journal of Contamination Hydrology, 33, 361-376 .

Johnson, C. A. , Schaap, M. G. , & Abbaspour, K. C. (2001): Model comparison of flow through a municipal solid waste incinerator ash landfill . Journal of Hydrology, 243, 55-72 .

10.

Kräuchi, P. & Gubler, R. (1992): Kehrichtschlacke als Strassenbaumaterial. Diplomarbeit ETH Zürich.

11.

Lanz, C. (1995): Wasserhaushalt einer Kehrichtschlackendeponie. Diplomarbeit ETH Zürich.

12.

Lichtensteiger, T. (1996): Müllschlacken aus petrologischer Sicht. Geowissenschaften Nr.5, Verlag Ernst&Sohn.

13.

Mualem, Y. (1976): A new model for predicting the hydraulic conductivity of unsaturated porous media . Water Resources Research 2(3), 513-522 .

14.

Rawls, W.J. & Brakensiek, D.L. (1989): Estimation of soil water retention and hydraulic properties. In: Unsaturated Flow in Hydrological Modeling, Morel-Seytoux, H.J. (ed.). Kluwer, Dordrecht, The Netherlands .

15.

Richards, L.A. (1931): Capillary conduction of liquids through porous media . Physics 1: 318-333 .

16.

Scheffer, F. , Schachtschnabel, P. , Blume, H.-P. , Brümmer, G. , Hartge, K.-H. , & Schwertmann, U. (1989): Lehrbuch der Bodenkunde, 12. Auflage. Enke, Stuttgart, Germany .

17.

Schroeder, P. , Lloyd, C. , Zappi, P. , & Aziz, N. (1997): The Hydrologic Evaluation of Landfill Performance (HELP) Model: Engineering Documentation for Version 3. United States Environmental Protection Agency, Washington DC, USA .

18.

Schumacher, W. (1864): Die Physik des Bodens. Wiegandt & Hempet, Berlin, Germany .

19.

Simunek, J. , Huang, K. , van Genuchten, M.T. , & Sejna, M. (1998): Hydrus- 1D, Version 2.0, Code for simulating the One Dimensional Movement of Water, Heat, and Multiple Solutes in Variably Saturated Porous Media. US Salinity Laboratory, USDA, ARS; Riverside, CA, USA .