Steelmaking slag for fertilizer raw material, manufacturing method of steelmaking slag for fertilizer raw material, manufacturing method of fertilizer and fertilization method

摘要

An object of the present invention is to supply various types of elements as plant fertilizers easily and at low cost without runoff due to water flow, even in acidic soils in areas with high rainfall and areas with high river flow. SOLUTION: The steelmaking slag for fertilizer raw material according to the present invention is, by mass%, P2O5: 2% to 8%, MnO: 3% to 10%, boron: 0.005% to 0.05%, Total iron: 7% to 15%, CaO: 38% to 48%, SiO2: 22% to 30%, sulfur: 0.1% to 0.6%, MgO: 1% to 8%, Al2O3: containing 0.5% or more and 3% or less, the proportion of soluble P2O5 in P2O5 is 50% or more, the proportion of semisoluble MnO in MnO is 80% or more, and slag basicity However, it is more than 1.5 and 2.2 or less, and bulk specific gravity is 1.9 or more and 2.8 or less. 【Selection chart】 None