Phosphogypsum is a waste of the phosphoric acid production, which is a principal constituent of the modern fertilizer. Many attempts of its development in various domains were indicated by several authors. Phosphogypsum is used in building materials in many countries (Japan, Australia ...) especially in the fabrication of plaster after elimination of awkward impurity contained in phosphogypsum or after adaptation of industrial process to obtain a phosphogypsum more pure. Concerning Tunisia, the natural gypsum of good quality exists in many regions. This gypsum is employed among others to manufacture plaster for which consumption at the national level is less than 0.1 million tons per year. The purification of phosphogypsum for use in the plaster industry is not competitive for Tunisia. A future potential of employment of phosphogypsum not purified as a construction material comes to light in the fabrication of bricks and of blocks produced by static press process. This paper presents results of a study of physical and mechanical properties of bricks of tunisian phosphogypsum raw or mixed up with other materials obtained by static press. These results show that certain mixing processes have the minimal criteria of strength allowing an eventual development of phosphogypsum in the building sector, to be considered in Tunisia.
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