PHOSPHATE FERTILIZER, AND METHOD FOR PRODUCING PHOSPHATE FERTILIZER

• Main Authors: NAKAMURA HIROSHI, IWATA TAKASHI, HASHIMOTO MITSUFUMI, KARIBE HAJIME, SAKAMOTO YOSHIAKI, IMAI TOSHIO, NISHIMURA YASUMASA, TODA MASAYA, HIRABAYASHI KATSUKI, NOMURA KOJI, MIURA KEIICHI, MINOWA NOBUTAKA
• Format: Patent
• Language: English; French; German
• Published: 30.04.2014
• Subjects: CHEMISTRY; DISPOSAL OF SOLID WASTE; FERTILISERS; FERTILISERS PRODUCING CARBON DIOXIDE; INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; MANUFACTURE THEREOF; METALLURGY; ORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C, e.g. FERTILISERS FROM WASTE OR REFUSE; PERFORMING OPERATIONS; PHOSPHATIC FERTILISERS; RECLAMATION OF CONTAMINED SOIL SOIL; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

Provided are a phosphate fertilizer that has a high ratio of citric acid-soluble phosphate and can contribute to phosphorus resource saving and energy saving in fertilizer production, and a production method for a phosphate fertilizer. The phosphate fertilizer is obtained by firing a mixed raw material containing: sewage sludge and/or a sewage sludge-derived material; and a calcium source. In addition, the phosphate fertilizer has a content of CaO of 35 to 60 mass%, a content of SiO 2 of 5 to 35 mass%, a content of P 2 O 5 of 5 to 35 mass%, and a content of components except for CaO, SiO 2 , and P 2 O 5 of 30 mass% or less. Further, the production method for a phosphate fertilizer includes: a mixing step of mixing sewage sludge and/or a sewage sludge-derived material with a calcium source and optionally with a silica source to obtain a mixed raw material; and a firing step of firing the mixed raw material by using a firing furnace at 1,150 to 1, 350°C to obtain the phosphate fertilizer as a fired product.