Evaluating crystallization risks in liquefied-natural-gas (LNG) production

LNG is anticipated to dominate world energy trade and fill the gap between production and energy demands in few years, especially in the US. A key challenge during the production of LNG is that the presence of trace amounts of heavy components in the gas feed composition induces the precipitation of a solid phase during the cooling process, which presents the risk of equipment plugging and associated hazards. In light of this, thermodynamic predictive tools were evaluated for determining LNG crystallization conditions. Traditional modeling approaches using cubic EOS must be critically examined because of their widespread acceptance. However, results and its limitations must be seen in the light of scarce data available for validation. The promise in the area of molecular thermodynamics and emerging techniques that perform detailed microscopic simulations and derive fluid properties by taking appropriate statistical averages are highlighted.