Koji KUSHIDA

Development of High Quality Phosphate Fertilizer Production Technology that Uses Melting Process of Incinerator Ash of Sewage Sludge

Shoichi FUJITA , Toshiya KOMATSU , Shuji HIMENO


Phosphorus is valuable exhaustion resources. Using incinerator ash of sewage sludge as substitute of phosphate rock is important process for creating the Recycling-Based Society. In this study, we clarified the range of ash composition suitable for high quality slag fertilizer, and examined the heavy metals leaching from the slag fertilizer.

We determined the ash composition fulfilling the standard for P2O5 citrate soluble content. The results of content test indicate that fertilizer made from incinerator ash of sewage sludge fulfilled the standard of heavy metals content of Fertilizer Control Criteria. In addition, the results of citrate soluble leaching test indicate that the fertilizer components of P, Mg and K were selective leaching behavior, and the heavy metals of Cr and Pb were low leaching rate.