Effects of Phosphogypsum and Calcined Phosphogypsum Content on the Basic Physical and Mechanical Properties of Portland Cement Mortar

Abstract

Abstract Phosphogypsum (PG) is an industrial by-product from the wet manufacturing process of phosphoric acid production in the phosphating industry on rock phosphate. Indiscriminate dumping of PG results in soil, water, and air pollution and serious environmental damage (chemical and radioactive contamination). The application of PG as an additive in cement mortar was evaluated in this article. The properties of PG at 800°C in a muffle furnace and the effects on the mechanical behavior of cement have been studied in this article. The effect of using PG as a partial replacement for cement has been investigated by compressive and flexural strength tests. Water absorption, mortar consistency, dry bulk density, and water retention were also tested. Meanwhile, the internal structural characteristics of samples were determined though scanning electron microscopy analysis. By evaluating properties of mixture cement paste, according to the results of the study, it was determined that a cement mortar addition of 30 % calcined PG gave the optimum results. The mortar with calcined PG of 800°C has the characteristics of low density, light weight, and stable performance. Utilizing PG to produce cement mortar improves the mechanical property, while the environmental impact is negligible.