Conceptual Physicochemical Models for Scale Inhibitor-Formation Rock Interaction

Geomechanical effects of oilfield chemicals on sand failure in reservoir rocks

“…Four (4) sandstone and five (5) limestone samples were weighed and each of the sample was placed in a separate beaker and filled with one of the four different fluids -the brine, corrosion inhibitor, scale inhibitor and biocide -well enough to fully cover the core. The cores were allowed to remain in the fluids for one week to ensure complete saturation in line with the procedure reported by Oluyemi (2014). The cores were then removed from the fluids at the end of one week, rinsed with deionised water to prevent crystallisation of salt on the surface of the cores.…”

“…Also noted is a clear evidence of loose grain assemblages which resulted from the disintegration of the mineral constituent of the cores. The interaction of the chemicals with the rock materials contributed to the weakening of the grain fabrics of the core, resulting in the disintegration of the grainto-grain binding and eventual loosening and migration of sand grain (Oluyemi, 2014). Additionally, the presence of pitting in the SEM micrograph circled in Figure 5b which would have been made possible by the reaction of the chemicals with the feldspar is an evidence that dissolution/precipitation of certain minerals took place (Allen and Conca, 1991;Jordan et al, 1994).…”

“…Previous works (Wilson, 2016;Oluyemi, 2014;Mohamed and Nasr-El-Din, 2013;Denney, 2013;Bybee, 2010;Egermann et al, 2010;Tomson et al, 2008;Metcalf and Devine, 2004) studied the effects of interaction between chemicals like hydrochloric acid (HCl), carbon dioxide (CO2), brine and water (H2O), diethylenetriamine penta (methylene phosphonic acid) (DETPMP), 2,2 bis(4-hydroxyphenyl)-4-methylpentane (BHPMP) and the formation rock on the strength and petrophysical properties of sandstone and carbonate rocks. These studies were carried out to: (i) determine the mechanisms involved in the chemistry of water flow back in the water/shale interaction (Wilson, 2016); (ii) establish a fundamental knowledge on the behaviour of carbonate and clastic rocks in the presence of scale inhibitor (Oluyemi, 2014;Tomson et al, 2008); (iii) investigate the effect of CO2-carbonate rock interaction on the strength and petrophysical properties of the rock (Mohamed and Nasr-El-Din, 2013;Denney, 2013;Egermann et al, 2010); (iv) investigate wellbore integrity as it relates to CO2 migration during CO2/cement/brine interactions (Bybee, 2010); and (v) assess rock strength after acid fracture treatment using HCl (Metcalf and Devine, 2004).…”

Evaluation of Interactions Between Oilfield Chemicals and Reservoir Rocks

“…Tomson et al (2008) studied rock-phosphonate inhibitor interaction and the effect of metal ions on inhibitor retention under dynamic condition and revealed that inhibitor squeeze treatment can be improved by adding a compatible cation to control the acidity of the inhibitor pill. Oluyemi (2014) conducted a laboratory experiment on clashach cores under dynamic condition to investigate the likely effects of scale inhibitors (PTEMP) on the geomechanical strength and sand production potentials of sandstone reservoir. The results revealed sand failure and release of particles into the flow stream.…”

Development and Evaluation of an Environmentally Friendly Calcium Carbonate and Calcium Sulfate Scales Inhibitor

“…In some cases scale can even cause disastrous operational fail ures in cooling water systems [3,4]. Therefore, the consumption of inhibitors to reduce scaling has increased in recent years [8][9][10], Several studies about calcium carbonate and calcium sulfate scales formation in the absence and pre sence of inhibitors have been carried out [1][2][3][4][5][6][7][8][9][10][11][12][13]. To elimi nate or to reduce these problems, waters used in cooling sys tems are treated with inhibitive formulations.…”