Agronomic properties and heavy metals content in soil reclaimed from municipal solid waste landfill development of a knowledge-based system for foundry waste recycling

Landfill soils reclaimed from municipal solid waste landfill were characterized for agronomic properties and heavy metals. The samples were collected from Khon Kaen Municipality engineered landfill, Khon Kaen, Thailand, approximately aged 10-15 years, and screened with a 6.3-mm sieve. Chemical properties analysis was undertaken by appropriate procedure, and heavy metals were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). The landfill soil characteristics measured include pH, electrical conductivity (EC), cation exchange capacity (CEC), organic matter (OM), total N, available P, K, Mg and Ca; results obtained were 8.1, 4.2 dS/m, 4.4 cmol/kg, 4.9%, 0.27%, 23.2 mg/kg, 1.24 g/kg, 10.5 g/kg and 0.43 g/kg, respectively. The heavy metal contents in landfill soil included 2.0 As, 3.25 Cd, 3.3 Co, 38.0 Cr, 166.0 Cu, 1533.0 Fe, 0.72 Hg, 412 Mn, 22.0 Ni, 157.0 Pb, 1.0 Se, 44.0 Sn and 662 Zn mg/kg, respectively. These heavy metal concentrations were within permissible limits for land application described by Thailand and US EPA. This result indicated that municipal solid waste landfill had potential for recovery soil, and its use for soil amendment

Effects of residues from municipal solid waste landfill on corn yield and heavy metal content

The effects of residues from municipal solid waste landfill, Khon Kaen Municipality, Thailand, on corn (Zea mays L.) yield and heavy metal content were studied. Field experiments with randomized complete block design with five treatments (0, 20, 40, 60 and 80% v/v of residues and soil) and four replications were carried out. Corn yield and heavy metal contents in corn grain were analyzed. Corn yield increased by 50, 72, 85 and 71% at 20, 40, 60 and 80% treatments as compared to the control, respectively. All heavy metals content, except cadmium, nickel and zinc, in corn grain were not significantly different from the control. Arsenic, cadmium and zinc in corn grain were strongly positively correlated with concentrations in soil. The heavy metal content in corn grain was within regulated limits for human consumption