Mining, Metallurgy & Exploration, https://doi.org/10.1007/s42461-019-0082-6
This investigation of the petromineralogical studies of the late Paleocene–middle Eocene phosphatic nodules in the Dati-Dib area of Solan District is an attempt to study and observe the mineralogical characters, distribution pattern, texture and optical behavior of phosphate-bearing minerals and associated gangue in order to interpret the mode of their formation and depositional environment of the basin. The findings obtained from thin-section, X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM with EDX) studies indicate that the minerals’ different forms, textures and distributions in phosphatic nodules might be due to environmental vicissitudes in oxidizing to reducing conditions followed by replacement processes. Various separation methods and flowsheets are used to separate phosphate from gangue minerals in phosphate nodules. Based on the phosphate and gangue minerals present in the nodules, low-temperature roasting at 400 to 600 °C, combined with dry magnetic separation and high-intensity electrostatic separation, are used to separate phosphate from organic matter, sulfide minerals and quartz. The most important fertilizers produced are single and triple superphosphates (SSP, TSP) and ammonium phosphates (MAP, DAP).