喷射器内含湿含硫天然气形成水合物预测

针对高含硫气田天然气含湿含硫且井口压力不断降低的特点,利用高压气井的富余压力通过喷射器增压输送低压天然气。采用Fluent软件对喷射器内单相和气液两相含湿含硫天然气的沿程温度、压力进行了数值模拟,应用天然气水合物生成预测模型ZahediⅠ对天然气喷射器内部天然气水合物生成区域进行了预测分析,预测了工作流体入口温度、含硫量、含湿量对天然气水合物生成的影响。工作流体入口温度增加,喷射器内天然气水合物生成区域范围减小,硫化氢含量越高,天然气水合物生成区域范围越大,工作流体含水滴,喷射器内天然气水合物生成区域小于单相工质下的天然气水合物生成区域,进而提出了消除含湿含硫天然气喷射器内形成水合物的措施。

Prediction of hydrate formation of natural gas containing moisture and sulfur in ejector

For the continuous decrease in the wellhead pressure of natural gas containing moisture and sulfur in gas fields with high quantities of sulfur, low-pressure gases are transported owing to the surplus pressure from high-pressure gas wells via ejectors. Herein, the Fluent software is used to numerically simulate temperature and pressure profiles for single- and two-phase flows of natural gas containing moisture and sulfur in an ejector. The ZahediⅠmodel is used to predict the formation area of natural gas hydrates in the ejector. The effect of the inlet temperature of the working fluid, sulfur content, and moisture content on the formation of natural gas hydrates is predicted and analyzed. With increasing inlet temperature of the working fluid, the generation area range of natural gas hydrates in the ejector decreases. When the sulfide content is high, the generation area range of natural gas hydrates is large. The working fluid contains water droplets. The generation area of natural gas hydrates in the ejector is smaller than that under a single-phase working medium. Based on these results, measures for reducing natural gas hydrates are proposed.