The preparation of coal aqueous suspension was followed by simple physical methods. It requires the use of surfactants, additives (salt or base) or additions such as lignosulphonates and phosphates. The prepared suspensions in presence of the surfactant, Surfaron S 1520 N, proved to be the least stable; the presence of salt, and mainly ammonia, has a positive effect on fluidity and stability. The emulsions obtained in the simultaneous presence of lignosulphonate (Vanisperse) and of phosphate (TPPNa) conducted in a concentrated medium (70% of coal mass) has stable products. The determinant factor in that case is the ratio: TPPNa concentration / Vanisperse concentration.
T. Hamiah, A. Bouassida