| 摘要 |
PROBLEM TO BE SOLVED: To provide a phosphate fertilizer having high quality even at a low firing temperature, and a production method thereof.SOLUTION: A phosphate fertilizer is obtained by firing a preparation raw material comprising: at least one kind selected from sludge, dried sludge, carbonized sludge, sewage sludge incineration ash, and sewage sludge molten slag; and a magnesium source. The content ratio of MgO is 10 to 25 mass%. A production method of the phosphate fertilizer comprises: a preparation step of mixing the sludges and the magnesium source thereby obtaining the preparation raw material; and a firing step of firing the raw material at 950 to 1100°C using a firing furnace thereby obtaining the phosphate fertilizer as a fired product. |
