Silica transport during steam injection into oil sands

Interactions between silica sand and sodium silicate solution during consolidation process

“…As cristobalite and quartz are both different crystallized phases of silica, the precipitation mechanism of these two components could be the same. Bird et al [18] who have conducted studies on dissolution and precipitation kinetics of quartz have given same conclusions.…”

“…The deposition of silica species layer occurs only for saturated solution (Ks = 6.02 10 − 3 ) [47][48][49]. Therefore, the increase in temperature would lead to an increase in concentration of the dissolved silica to a raise in medium in which the concentration of silica is close to the saturation leading to a precipitation of silicate species: the silicate species dissolution/precipitation phenomenon [50,51]. Silicate species dissolution and silicate species precipitation could result in reaction mechanism described in Eqs.…”

Physico-chemistry of silica / Na silicate interactions during consolidation. Part 2: Effect of pH

“…Silica precipitation occurs when the solution becomes oversaturated caused by the increase in dissolved silicate species [18,19]. Actually, many investigations performed on silica minerals (quartz, cristobalite and amorphous silica) dissolution and precipitation, has shown that silica can precipitate hydrothermally from monomeric silica solutions only at concentrations above silica saturation and where precursor nuclei are present [20,21].…”

Acceleration effect of sulfate ion on the dissolution of amorphous silica

“…1. According to kinetic studies on the dissolution and deposition of amorphous silica, the dissolution reaction and the deposition reaction (polymerization by condensation reaction of Si(OH) 4 to Si-O − group on the surface of silica) have been regarded as zero and first-order reactions, respectively [13,14]. The analysis was performed using the method mentioned by Bird et al [14].…”