Modeling and simulation of sodium chloride's solubility in mixtures with water and Monoethylene glycol.
Monoethylene glycol. Sodium chloride. Simulation. Precipitation. Solubility. Statistical Analysis of Regression. MEG Regeneration.
Monoethyleneglycol (MEG) is used in the production of natural gas as an inhibitor of hydrate formation, reducing the freezing point in the ducts and protecting against corrosion. Hydrates are crystalline solids that can cause blockages of ducts in the flow of gas production. The produced water is saline, and thus the presence of salts can cause fouling in the MEG regeneration unit. The use of MEG has already known efficacy in the operating environment with respect to hydrate formation prevention. However MEG needs to be regenerated and reused in the system. It is at this stage that technical difficulties may occur due to the presence of MEG. This substance reduces the sodium chloride solubility in the produced water. If this salt concentration is above solubility, undesired crystals precipitation may occur in the MEG regeneration unit. This precipitation can cause problems such as fouling, which is very damaging to the equipment that makes up the regeneration system. Thus, it’s primary importance to know the salt solubility limits under the MEG process conditions. From the operational view point, it’s also important to quantify, in an agile way, how close the system is to salt crystallization. This can be accomplished through the use of a computer simulator that can, from the plant operating conditions and also laboratory data, calculate in a timely manner the species concentrations and, if necessary, the amount of crystallized salt throughout the MEG regeneration process. The purpose of this work is to create a simulator that can perform mass balance calculations to determine the salt concentration and, by knowledge of solubility, to quantify the salt crystals.