The K2OCaOSiO2 crystal material and gentle effective Characteristic potassic fertilizer

摘要

PROBLEM TO BE SOLVED: To obtain a slightly water-soluble new material suitable for a slow acting potash fertilizer by preparing a K2O-CaO-SiO2 crystal material. ;SOLUTION: The crystal material has a crystal structure of K2-2CaO-2SiO2 and is obtained by sintering a feedstock containing K2O, CaO and SiO2 in a molar ratio of 1:2:2 in the air. The amount of water-soluble K2O (water soluble rate) is 16.4% and the amount of citric-soluble K2O (citric soluble rate) is 98.7%. The slow acting potash fertilizer is based on crystals of K2-2CaO-2SiO2 and may partially contain a K2O-containing glass body. The feedstock is prepared by subjecting blast furnace slag or blast furnace pig iron to desiliconization, dephosphorization and desulfurization and adding a source of potassium to the resulting slag. The feedstock having a composition capable of crystallizing K2-2CaO-2SiO2 is melted at about 1,300-1,500°C and slowly cooled to crystallize the whole, or a part is crystallized by slow cooling in the early stage and then the remainder is vitrified by rapid cooling.;COPYRIGHT: (C)2000,JPO