Engineering Properties of Wade Sand-Lime- Cement-Phosphogypsum Building Brick Grade

Abstract-This study concerns the analysis of wade sand-natural hydraulic lime-cement-phosphogypsum (WS-NHL-C-PG) solid bricks grade MW. In Tunisia, for several years, a set of phosphoric acid production factories have produced a waste product such as phosphogypsum (PG) in large quantities (approximately 10 million tons per year). Currently, in Sfax (Center-East of Tunisia), the PG is stored into piles in the vicinity of the factory, by dry or wet process. The storage of PG, even though presenting a low radioactivity, causes pollution to the water table and to the soil (due to the infiltration of acid and heavy metals). After treatment, the Tunisian PG was presented in the full bricks with different mass percentages of 60, 70 and 80%. The study involved physical, chemical, mechanical and environmental tests on the obtained bricks. The obtained results showed that WS-NHL-C-PG bricks successfully satisfied the standard requirements of bricks grade MW. Notwithstanding the techno-economic virtues, phosphogypsum-based bricks comply with the criteria for environmentally friendly products manufactured with industrial by-product and the manufacturing process is totally energy conservative