The use of phosphogypsum for soil bricks manufacturing as an alternative for its sustainable destination

This research studies soil-compacted bricks using phosphogypsum (PG) in their dosage. Laboratory tests were performed to assess these bricks’ physical characteristics. To obtain the bricks, two dosages were used: 4 and 7% of phosphogypsum (PG) concentration. Bricks with no phosphogypsum (PG) in their mixture were also assessed as a benchmark. The brick’s physical characteristics were obtained by bricks dried by the sun and in an oven at 900 °C for 96 h. The results of the laboratory tests were analyzed through statistical analysis to explore the differences between the means for each studied condition (dosage and drying method). We found no statistically significant difference between the mean strength of bricks with 4% phosphogypsum (PG) in their dosage and bricks with no PG. Beyond 4% of the phosphogypsum (PG) dosage, the brick’s strength presented a reduction. For all dosages, bricks dried in the oven showed higher strength than bricks dried in the sun. However, according to the Brazilian Technical Standards, all studied bricks presented enough strength to be used in regular construction. Therefore, phosphogypsum (PG) for brick manufacturing can be an alternative disposal method, which can help mitigate the civil construction environmental impacts.