Sulfate Resistance in Cements Bearing Bottom Ash from Biomass-Fired Electric Power Plants

Applied Sciences

MaríaIsabel Sánchez de Rojas¹  Moisés Frías¹  IsabelF. Sáez del Bosque²  JoséM. Medina²  César Medina³ 

[1] Departamento de Cementos y Reciclado de Materiales, Instituto de Ciencias de la Construcción Eduardo Torroja (IETcc-CSIC), 28033 Madrid, Spain;Departamento de Construcción, Escuela Politécnica de Cáceres—Grado de Ingeniería Civil, Universidad de Extremadura, Instituto de Investigación de Desarrollo Territorial Sostenible (INTERRA), 10003 Cáceres, Spain;Sostenibilidad en Materiales de Construcción, Universidad de Extremadura, Unidad Asociada al CSIC, Departamento de Construcción, Instituto de Investigación de Desarrollo Territorial Sostenible (INTERRA), Escuela Politécnica de Cáceres—Grado de Ingeniería Civil, Universidad de Extremadura, 10003 Cáceres, Spain;

关键词: sulfate;    biomass ash;    durability;    sustainability;    binary cements;   

DOI  :  10.3390/app10248982

来源: DOAJ

【 摘 要 】

To address some of the gaps in the present understanding of the behavior of new supplementary cementitious materials such as bottom ash (BA) from biomass-fired electric power plants in cement manufacture, this study explored the effect of this promising material on the sulfate resistance of the end product. Cement paste prepared with 10% or 20% (previously characterized for mineralogy and chemical composition) BA was Köch–Steinegger tested for sulfate resistance. The hydration products, in turn, were analyzed before and after soaking the reference and experimental cements in sodium sulfate to determine whether the use of the addition hastened microstructural, mineralogical, or morphological decay in the material. The 56 days findings showed that the presence of BA raised binder resistance to sulfate attack. Köch–Steinegger corrosion indices of 1.29 and 1.27 for blended cements OPC + 10 BA and OPC + 20 BA, respectively, were higher than the 1.26 recorded for ordinary Portland cement (OPC). In addition, weight gain was 20.5% and volume expansion was 28.5% lower in the new materials compared to OPC. The products resulting from the external sulfate-cement interaction, gypsum and ettringite, were deposited primarily in the pores present in the pastes. The conclusion drawn is that binders bearing 10% or 20% BA are, a priori, apt for use in the design and construction of cement-based elements exposed to sulfate-laden environments.

【 授权许可】

Unknown