Comparison Of Chemical Properties And Application As Acid Soil Amendment Of Pretreatment Center Slag And Other Slags

Abstract

Chemical properties of Pretreatment center slag (PTC-slag) were analyzed and compared to those of converter slag (C slag) and blast f!-lrnace slag (BF slag). PTC slag had a high EC value as well as citric acid soluble P and contained more Ca, Si, P, K, and Na but less Mg and Fe than C slag. Compared to BF slag, PTC slag contained more Fe, Ca, Mg, P, Mn, and Na but less Si, AI, and K. Although neutralizing value of PTC slag was lower than that of C slag, its ability to neutralize soil acidity was markedly higher. A pot experiment using Andisol from T ochigi Prefecture and komatsuna plant was carried out to evaluate PTC slag as liming material as well as P fertilizer. PTC slag, C slag, and dolomite were applied as liming materials and combined with super phosphate (SP). Addition of SP of 2.5 and 5.0°A, phosphate absorption coefficient (PAC) to PTC slag significantly improved the yield of komatsuna. This result, however, only apply for PTC slag adjusting soil pH to 6.5. Addition of the same dosage of SP to PTC slag adjusting soil pH to 7.5 did not give significant effect. On the other hand, addition of SP of 2.5 and 5.0% PAC to C slag or dolomite dignificantly improved the yield for both C slag or dolomite adjustingthe soil pH to 6.5 and 7.5.