The aggressiveness of pig slurry to cement mortars

Abstract

The aim was to measure the behaviour of various mortars employed in livestock media in central Spain and to analyse the aggressiveness of pig slurry to cement blended with flyash mortars. To achieve this, mortar specimens were immersed in ponds storing pig slurry. Mortar specimens, of 40 x 40 x 150 mm, were made from four types of cement commonly used and recommended for rural áreas. The types were a sulphate-resistant Portland cement and three cements blended in different proportions with fly ash and limestone fiUer. After 3, 5, 12, 24, 35, 48 and 50 months of exposure, three or four specimens of each cement type were removed from the pond and washed with water. Their compressive strength and microstructure (X-ray diffraction, mercury intrusión pore-symmetry, thermal analysis and scanning electrón microscopy) were then measured. Sulphate-resistant Portland cement (SR-PC), found to be more susceptible to degradation due to its greater proportion of macro-pores and increased total porosity, was found not to be suitable for use with livestock. After 50 months of immersion in the pig slurry médium, CEM II-A (40.3%) mortar retained the greatest compressive strength. Mortars with less than 20% replacement of cement by fly ash were found to be the most durable, with the most suitable mechanical behaviour.

Resistance of CEM III/B based materials to acid attack

“…Ispitivani su malteri s razli itim tipovima mešanih i sulfatno otpornih cementa u svinjcima [15]. Otpornost betona od cementa s kre njakom [21] i cementa s lete im pepelom [26] na dejstvo sulfata pokazuje da sulfatno otporni cementi poboljšavaju hemijsku otpornost bez pove anja troškova.…”

“…Influence of pig slurry on mortar with different types of blended and sulphate-resistant cement was investigated [15]. Sulphate resistance of concrete with limestone cement [21] and fly ash cement [26] shows that sulphate-resistant cements improve the chemical resistance without cost increase.…”

Estudio microestructural de pastas de cemento expuestas a medios simulados de agresividad moderada frecuentes en ambientes rurales

“…En este sentido, los procesos de degradación que se desencadenan en los materiales pueden dan lugar al colapso de los elementos tanto estructurales como a las instalaciones (separadores, suelo discontinuos…) suponiendo un considerable gasto económico, ya sea por la muerte del animal o por el cese de la producción debido a las labores de las reparaciones que precisan (Massana et al, 2013).…”