Evaluating radiation risks and resource opportunities associated with phosphogypsum in the Philippines
Reymar R. Diwa, Estrellita U. Tabora, Botvinnik L. Palattao, Nils Haneklaus, Edmundo P. Vargas, Rolando Reyes, Jennyvi D. Ramirez
Abstract
Abstract Phosphogypsum (PG) accumulates during wet-phosphoric acid production for fertilizers. In the Philippines, PG is partly (40%) utilized to produce gypsum walls and cement. This work assesses the radiological risks and resource opportunities associated with PG stacks in the Philippines. The conducted in situ radiometric survey measured the activity concentrations of 40 K, 238 U, and 232 Th at 270 locations. Besides, another 120 surface samples were collected. Pure PG exceeds the recommended radiation limits, but simple dilution with conventional materials can make PG available as an inexpensive secondary raw material for construction. PG further contains relevant concentrations of rare earths and Y (195 ppm).