Microencapsulation of phosphogypsum into a sulfur polymer matrix: physico-chemical and radiological characterization |
| |
Authors: | López Félix A Gázquez Manuel Alguacil Francisco José Bolívar Juan Pedro García-Díaz Irene López-Coto Israel |
| |
Affiliation: | a Centro Nacional de Investigaciones Metalúrgicas (CENIM), CSIC, Avda. Gregorio del Amo, 8, 28040 Madrid, Spain b Departamento de Física Aplicada, Universidad de Huelva, Campus de El Carmen, 21071 Huelva, Spain |
| |
Abstract: | The aim of this work is to prepare a new type of phosphogypsum-sulfur polymer cements (PG-SPC) to be utilised in the manufacture of building materials. Physico-chemical and radiological characterization was performed in phosphogypsum and phosphogypsum-sulfur polymer concretes and modeling of exhalation rates has been also carried out. An optimized mixture of the materials was obtained, the solidified material with optimal mixture (sulfur/phosphogypsum = 1:0.9, phosphogypsum dosage = 10-40 wt.%) results in highest strength (54-62 MPa) and low total porosity (2.8-6.8%). The activity concentration index (I) in the PG-SPC is lower than the reference value in the most international regulations and; therefore, these cements can be used without radiological restrictions in the manufacture of building materials. Under normal conditions of ventilation, the contribution to the expected radon indoor concentration in a standard room is below the international recommendations, so the building materials studied in this work can be applied to houses built up under normal ventilation conditions.Additionally, and taking into account that the PG is enriched in several natural radionuclides as 226Ra, the leaching experiments have demonstrated that environmental impact of the using of SPCs cements with PG is negligible. |
| |
Keywords: | PR, phosphate rock PG, phosphogypsum PCC, portland cement clinker SPC, sulfur polymer concrete PG-SPC, phosphogypsum-sulfur polymer concrete STX&trade , sulfur modified I, external risk index Ra(eq), equivalent radium concentration Ac (%), coefficient of absorption with respect to the pH Lc (%), leaching coefficient for 238U and 210Po at the different pHs |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|