Aqueous dispersions of heavy oil residues

A process for combustion of heavy oil residues with a low emission of SOx comprising:

• heating the heavy oil residues at a temperature at least equal to a softening point of the heavy oil residues;
• preparing a dispersion of the heated heavy oil residues in water, and
• combusting the dispersion of the heavy oil residues in water;
• wherein the heavy oil residues have a softening point higher than 25° C., and
• wherein the dispersion of the heavy oil residues in water comprises:
• one or more dispersing agents selected from organic sulfonates of alkali metals or of ammonium;
• one or more desulfurizing agents selected from the group consisting of CaCO3, MgCO3, dolomite and relative mixtures;
• and
• one or more desulfurizing agents with stabilizing and anticorrosive properties selected from the group consisting of MgO, Mg (OH)2, CaO, Ca(OH)2 and relative mixtures;
• wherein
• the dispersion of heavy oil residue in water has a water content of at least 15%,
• the dispersing agent in the form of the sodium salt has the following properties:
• (A) a sulfur content of at least 10% by weight;
• (B) a solubility in water at 20° C. of at least 15% by weight;
• (C) a reduction in the surface tension in water, at a concentration of 1% by weight, lower than 10%;
• the desulfurizing agents are present in a quantity ranging from 0.5 to 3.0 moles with respect to the sulfur contained in the heavy oil residue, and
• the desulfurizing agents with stabilizing and anticorrosive properties are present in a quantity ranging from 0.04% by weight to 0.4% by weight with respect to the total suspension.