摘要:
[PROBLEM] To recover phosphorus accumulated in a sewage-treatment plant or the like at a low cost in such a manner as to facilitate the utilization of the thus recovered phosphorus. To efficiently utilize the recovered phosphorus as a fertilizer. [SOLUTION] Phosphorus in waste water, which is a phosphorus source, is adsorbed by a phosphorus recovery material formed of an amorphous calcium silicate-based material and thus recovered. After adding the phosphorus recovery material to the waste water that is a phosphorus source, it is preferred to adjust the pH value of the waste water to 7.0 or higher. Also, it is preferred that the waste water that is a phosphorus source is decarbonated by reducing the pH value thereof to 6.0 or lower and then the phosphorus recovery material is added. As the phosphorus recovery material, an aggregate of an amorphous calcium silicate hydrate and Ca(OH) 2 and having a Ca/Si molar ratio of 0.8-20 inclusive is preferred. The aggregate may be obtained by solid-liquid separation and drying. Alternatively, a slurry or paste containing the aggregate may be used. The recovered phosphorus recovery material can be used as a fertilizer.
摘要:
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.
摘要翻译:提供了具有高柠檬酸可溶性磷酸盐比例的磷酸盐肥料,可以有助于磷肥资源节约和节约化肥的生产,以及磷肥的生产方法。 通过焙烧含有污水污泥和/或污水污泥来源的材料的混合原料获得磷酸盐肥料; 和钙源。 另外,磷酸肥料的CaO含量为35〜60质量%,SiO 2的含量为5〜35质量%,P 2 O 5的含量为5〜35质量%,除了 对于CaO,SiO 2和P 2 O 5为30质量%以下。 此外,磷酸肥料的制造方法包括:将污水污泥和/或污水污泥来源的材料与钙源和任选的二氧化硅源混合以获得混合原料的混合步骤; 以及通过使用1150〜1 350℃的烧成炉对混合原料进行烧成,从而得到作为烧成品的磷酸盐肥料的烧成工序。
摘要:
[PROBLEM] To recover phosphorus accumulated in a sewage-treatment plant or the like at a low cost in such a manner as to facilitate the utilization of the thus recovered phosphorus. To efficiently utilize the recovered phosphorus as a fertilizer. [SOLUTION] Phosphorus in waste water, which is a phosphorus source, is adsorbed by a phosphorus recovery material formed of an amorphous calcium silicate-based material and thus recovered. After adding the phosphorus recovery material to the waste water that is a phosphorus source, it is preferred to adjust the pH value of the waste water to 7.0 or higher. Also, it is preferred that the waste water that is a phosphorus source is decarbonated by reducing the pH value thereof to 6.0 or lower and then the phosphorus recovery material is added. As the phosphorus recovery material, an aggregate of an amorphous calcium silicate hydrate and Ca(OH) 2 and having a Ca/Si molar ratio of 0.8-20 inclusive is preferred. The aggregate may be obtained by solid-liquid separation and drying. Alternatively, a slurry or paste containing the aggregate may be used. The recovered phosphorus recovery material can be used as a fertilizer.