Preliminary studies of a phosphogypsum stabilisation process using a sulphur polymer matrix

The production of phosphoric acid from natural phosphate rock by means of the wet process gives rise to an industrial by-product named phosphogypsum (PG). World PG generation is estimated to be around 100-280 million tonnes/year. PG is mainly composed of gypsum but also contains a high level of impu...

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Detalles Bibliográficos
Autores: Tayibi, Hanan, López-Delgado, Aurora, Choura, Mohamed, Gascó, Catalina, Navarro, Nuria, Alguacil, Francisco José, López Gómez, Félix Antonio
Tipo de recurso: artículo
Fecha de publicación:2009
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/11233
Acceso en línea:http://hdl.handle.net/10261/11233
Access Level:acceso abierto
Palabra clave:phosphogypsum
radionuclides
sulphur polymer concrete
stabilisation/solidification
TENORM
Descripción
Sumario:The production of phosphoric acid from natural phosphate rock by means of the wet process gives rise to an industrial by-product named phosphogypsum (PG). World PG generation is estimated to be around 100-280 million tonnes/year. PG is mainly composed of gypsum but also contains a high level of impurities such as phosphates, fluorides, naturally occurring radionuclides, heavy metals, and other trace elements. All of this adds up to a negative environmental impact and many restrictions on PG applications. PG is disposed of without any treatment, usually by dumping in large stockpiles that occupy considerable land areas and cause serious environmental damage, particularly in coastal regions. The USEPA has classified PG as a “Technologically Enhanced Naturally Occurring Radioactive Material” (TENORM). This paper reports a proposed PG stabilisation/solidification (S/S) process by means of sulphur polymer concrete. Final products have been obtained in the form of standard monoliths. Mechanical properties (compressive and flexural strength) have been studied and radionuclide contents determined. Results show the obtainment of sulphur and phosphogypsum concretes with good mechanical properties and low radionuclide contents. The PG S/S process can thus be considered a very suitable and efficient option for PG disposal.