Análise comparativa entre as características químicas do gesso e do fosfogesso após beneficiamento térmico

Abstract

The phosphogypsum residue, generated in the production of fertilizers, represents a problem for both the industries that have few disposal options and those who are affected by the environmental impact caused by their incorrect disposal in piles. The use of phosphogypsum in total or partial replacement of gypsum in civil construction would mean the reduction of the environmental impact, possible reduction of the cost of production and transportation and reduction of gypsum deposits exploitation. The present work has the objective of analyzing the chemical characteristics of phosphogypsum, in natura and after thermal processing, for use as civil construction gypsum. For this purpose, chemical characterization and mechanical tests were carried out with phosphogypsum and a commercial gypsum powder, and the results were compared with previous studies. Despite showing a very low mechanical resistance in comparison to the commercial gysum plaster, from the results obtained it was possible to observe that the thermal processing of the phosphogypsum resulted in a material of chemical composition similar to that of the commercial gypsum powder, proving to be an essential process for the use of phosphogypsum in civil construction.