Role of Polyelectrolytes in Barium Sulphate Precipitation

摘要

In the last decades, the use of additives in precipitation processes to improveprocess efficiency as well as product performance became more and more common practice. Additives alter the surface properties of the crystals which leads to changes in nucleation and growth kinetics, and thereby to changes in the shape of the crystals as well as in their agglomeration or dispersion behavior. The precipitation of barium sulfate from aqueous solutions was selected as a model system for studying the effects of additives both because of its practical advantages and its industrial relevance. Barium sulfate is a notorious problem as an unwanted deposition in the offshore oil and gas recovery. The treatment of the barium sulfate-scale problem is mainly focused on its prevention by the addition of scale-control additives. The additives selected for the investigation are (poly)phosphonate and polycarboxylate compounds, some of which are commercially available for scale prevention.