Abstract:
The chemical binder is one of the critical factors affecting ore agglomeration behavior and leaching efficiency. In this study, we investigated the effect of the type of binder and mass fraction of the H
2SO
4 solution used on the curing, soaking, and leaching behavior of agglomerations. The results revealed that Portland cement (3CaO·SiO
2, 2CaO·SiO
2, and 3CaO·Al
2O
3) was the optimal binder for obtaining a well-shaped, stable agglomeration structure. A higher extraction rate was achieved when using Portland cement than that obtained using sodium silicate, gypsum, or acid-proof cement. An excessive geometric mean size is not conducive to obtaining well-shaped agglomerations and desirable porosity. Using computed tomography (CT) and MATLAB, the porosity of two-dimensional CT images in sample concentrations L1–L3 was observed to increase at least 4.5vol% after acid leaching. Ore agglomerations began to be heavily destroyed and even to disintegrate when the sulfuric acid solution concentration was higher than 30 g/L, which was caused by the excessive accumulation of reaction products and residuals.