An Experimental Project to Determine the Parameters of Silica Scaling in Reverse Osmosis Systems

摘要

The objective of this work was to better define, on the basis of literature research and laboratory experiments in glassware and small reverse osmosis systems, how various parameters affect the concentration limits at which silica scaling occurs, and what the mechanisms of scaling are. The specific parameters studied were silica supersaturation, temperature, pH, and brine composition and concentration. Silica chemistry was found to be extremely complex, involving several different silica species and several mechanisms for removal of silica from solution. In addition, a wide variety of parameters were found to have effects on silica scaling, by affecting solubility, scaling mechanism, the kinetics of the mechanism, or a combination of these. This report provides a conceptual model of the types of silica scaling which may occur, and the situations in which they may occur, and presents experimental data consistent with the model.