| 摘要 |
PROBLEM TO BE SOLVED: To provide a phosphate fertilizer or the like which has high phosphorous solubility in an aqueous citric acid solution and high silicic acid solubility, and can contribute to the saving of phosphorus or the saving of energy in the production of the fertilizer; and to provide a method for producing phosphate fertilizer.SOLUTION: The phosphate fertilizer is produced by firing a mixed raw material comprising sewage sludge and/or a material derived from the sewage sludge and at least, as calcium sources, livestock feces and/or a material derived the livestock feces. The phosphate fertilizer has a CaO content of 25-55 mass%, a Ca/P molar ratio of 2.0-7.5, and an AlOcontent of 19 mass% or less. A method for producing the phosphate fertilizer is also provided. |
