عنوان مقاله [English]
In this study fertilizing potential of municipal solid waste (MSW) compost was investigated by the distribution behavior of heavy metals, nutrient elements and salinity content among the different size fractions. Therefore, 3 compost samples (each composed of 6 subsamples) were collected from Sanandaj MSW Composting Plant. Then, the samples were physically divided into seven fractions of different particle size including >2, 1.2-2, 0.8-1.2, 0.4-0.8, 0.2-0.4, 0.1-0.2 and <0.1 mm, using dry-sieving process. The bulk sample was reserved as control. The results showed that by decreasing of particle size, pH values decreased, however, other surveyed parameters increased. The highest concentration of EC, Zn, Cu, Cd, Pb, Ni, Cr, Mn, N, P, Ca and K was found in the finest fraction (<0.1 mm) with average values of 9.1 dSm-1, 714.4, 450.5, 4.2, 315.5, 55.1, 40.7, 468.5 ppm, 3.0, 1.5, 6.9 and 0.9 % respectively, whereas the lowest concentration were found in the coarsest fraction (>2 mm). Overall, the results suggest that the size fractions less than 0.4 mm with highly heavy metals and salinity content and size fractions more than 2 mm with high impurity (glass, 21.2 times over the permissible limit) were responsible for lowering the quality of the produced compost, thus, removal of selected fractions particle size could significantly improve the compost quality and allowed us to use and its safe recycle in agriculture.