Abstract
The data on scale inhibition mechanisms are critically analyzed with the emphasis on the published data disparity and controversy. On the grounds of three independent approaches it is demonstrated that foreign background “nanodust” particles have a dramatic impact on antiscalant efficacy. These approaches include: (i) a direct nanoparticle counter application in stock solutions; (ii) a novel DLS special technique, based on the standard nanoparticles injection into the supersaturated inorganic salt solution during the induction period; and (iii) an application of fluorescent-tagged antiscalants for the direct visualization of a scale inhibitor during scale formation.
It is demonstrated, that foreign solid nanoparticles (“nanodust”) appear to be inevitable component of any process in aqueous phase. A non-conventional mechanism of scale inhibition is proposed. It states, that a pre-nucleation step of inorganic scale formation in the bulk aqueous phase takes place not so much as a spontaneous homogeneous ion pairs or clusters formation, but as a heterogeneous formation on a “nanodust” particles surface. Thus an antiscalant destabilizes this process by “nanodust” particles surface blockage instead of unclear impact on homogenious clusters spontaneous formation. In this sense a “nanodust” approach provides a different look at the threshold effect and at its mechanism. It is shown that the visualization of antiscalant is a very promising and universal tool for reagent traceability, and for industrial equipment fouling diagnostics.
