The industrial production of the phosphoric acid is important and makes itself in a big number of countries. The by-product descended of this industry, residuary gypsum called phosphogypsum, poses a major environmenta...The industrial production of the phosphoric acid is important and makes itself in a big number of countries. The by-product descended of this industry, residuary gypsum called phosphogypsum, poses a major environmental problem. The aim of this work is to identify and to value the potentialities of valorization of the by-product phosphogypsum produce in Morocco, for a use in the domain of agriculture. They can contain 1% to 6% of free acids. The idea is to use this acid to partially solubilize natural phosphate and to make the final product richer in phosphorus （about I0% of total P205 half soluble） and therefore more attractive on the agronomic and economic plan. For mixtures phosphogypsum/natural phosphate, a study of clarification is necessary, by varying the proportions of products, the humidities, mixing techniques, the ripening time to achieve a final interesting product. The dynamics of the phosphor in soil has been measured by the Olsen method and the one in the plant has been measured after drying in the steamroom to a temperature of 70 ~C to 75 ~C during 72 hours. A trial hold is incinerated. The ashes are taken by acid hydrochloric extract and the phosphor is measured out with the help of an UV spectrometer to 430 nm. The pH has been followed with the help of a pH-meter. The phosphor presents a remarkable dynamics in mixture with the phosphogypsum.展开更多
文摘The industrial production of the phosphoric acid is important and makes itself in a big number of countries. The by-product descended of this industry, residuary gypsum called phosphogypsum, poses a major environmental problem. The aim of this work is to identify and to value the potentialities of valorization of the by-product phosphogypsum produce in Morocco, for a use in the domain of agriculture. They can contain 1% to 6% of free acids. The idea is to use this acid to partially solubilize natural phosphate and to make the final product richer in phosphorus （about I0% of total P205 half soluble） and therefore more attractive on the agronomic and economic plan. For mixtures phosphogypsum/natural phosphate, a study of clarification is necessary, by varying the proportions of products, the humidities, mixing techniques, the ripening time to achieve a final interesting product. The dynamics of the phosphor in soil has been measured by the Olsen method and the one in the plant has been measured after drying in the steamroom to a temperature of 70 ~C to 75 ~C during 72 hours. A trial hold is incinerated. The ashes are taken by acid hydrochloric extract and the phosphor is measured out with the help of an UV spectrometer to 430 nm. The pH has been followed with the help of a pH-meter. The phosphor presents a remarkable dynamics in mixture with the phosphogypsum.
