Singh Maneesh, Kapur P C
Tata Research, Development and Design Centre, 54B Hadapsar Industrial Estate, Pune 411013, India.
J Hazard Mater. 2008 Aug 30;157(1):106-13. doi: 10.1016/j.jhazmat.2007.12.117. Epub 2008 Jan 17.
Phosphochalks from fertiliser plants contain significant amount of calcium sulphate along with P(2)O(5) and fluorine. The presence of these impurities makes them unsuitable for most applications and, hence its availability in millions of tons. We demonstrate that it is possible to prepare calcium sulphoaluminate-aluminoferrite based special cements having strength values comparable to ordinary Portland cement (OPC) using these waste chalks. Such cements are insensitive to the presence of impurities in the raw mixture, clinker at low temperatures (1,230 degrees C) and the clinkers produced are soft and friable. An empirical technique has been developed to predict the phase composition of the clinkers given the chemical composition of the starting raw mixture. The proposed low temperature clinkering route appears to be a promising method for converting waste phosphochalks into construction grade cements.
化肥厂的磷钙石含有大量硫酸钙以及五氧化二磷和氟。这些杂质的存在使其不适用于大多数应用，因此有数百万吨的磷钙石无法得到利用。我们证明，使用这些废磷钙石可以制备出强度与普通硅酸盐水泥（OPC）相当的硫铝酸钙 - 铁铝酸盐基特种水泥。这种水泥对生料混合物中杂质的存在不敏感，在低温（1230摄氏度）下就能烧结，并且所生产的熟料柔软易碎。我们开发了一种经验技术，根据起始生料混合物的化学成分来预测熟料的相组成。所提出的低温烧结路线似乎是将废磷钙石转化为建筑级水泥的一种有前景的方法。
