The Effect of Monoethylene Glycol on Calcium Carbonate Solubility at High Temperatures

Copyright © 2018 American Chemical Society. This study presents the solubility of calcium carbonate in monoethylene glycol (MEG)/water solution at high temperatures and high MEG concentrations. The conditions simulate the water removal process during MEG regeneration. Solubility was measured by dissolution at equilibrium, and the thermodynamics of the dissolution process of calcium carbonate was also explored. The solubility of calcium carbonate decreased with increasing temperature up to 120 °C and showed a slight increase above 120 °C. The presence of MEG increased the activity coefficient of calcium carbonate and calcium ions with respect to temperature. The effect of MEG degradation on the solubility of calcium carbonate was also studied. At all temperatures studied (90 to 145 °C), MEG degraded in the presence of residual dissolved oxygen to produce acetate ions which complexed with calcium ions resulting in an increase in calcium solubility

Microfluidic Model Porous Media: Fabrication and Applications

Complex fluid flow in porous media is ubiquitous in many natural and industrial processes. Direct visualization of the fluid structure and flow dynamics is critical for understanding and eventually manipulating these processes. However, the opacity of realistic porous media makes such visualization very challenging. Micromodels, microfluidic model porous media systems, have been developed to address this challenge. They provide a transparent interconnected porous network that enables the optical visualization of the complex fluid flow occurring inside at the pore scale. In this Review, the materials and fabrication methods to make micromodels, the main research activities that are conducted with micromodels and their applications in petroleum, geologic, and environmental engineering, as well as in the food and wood industries, are discussed. The potential applications of micromodels in other areas are also discussed and the key issues that should be addressed in the near future are proposed