高含硫气井井筒硫沉积位置预测模型研究

高含硫气井在气体开采过程中，随着井筒温度压力的降低，硫微粒在气相中的溶解度逐渐减小，在达到临界饱和态后将从气相中析出，当井筒中硫析出位置处的气流速度小于微粒临界悬浮流速时，析出的硫微粒在井筒中沉积，堵塞气体的流动通道，从而导致气井产量降低，影响气井的产能和经济效益，严重时造成气井停产。将井筒压力温度分布预测模型与硫溶解度模型耦合，结合井筒中微粒临界悬浮流速模型建立了高含硫气井井筒硫沉积预测综合模型，并对L 井进行了实例分析。研究结果表明：高含硫气井产量降低至临界产量后，随着气井产量的降低，井筒中气流速度逐渐减小，硫沉积区域沿井筒向下逐渐增加。

FORECAST MODEL OF LOCATION OF SULFUR DEPOSITION IN THE WELL BOREOF HIGH SULFUR GAS WELL

During the course of production of high sulfur gas well, temperature and pressure falls continually along well bore, solubility of sulfur particles in gas phase declines, and sulfur particle precipitate in well bore from gas phase after running up to saturation state if velocity of gas is less than critical sustaining velocity of particle, sequentially resulting in blockage of gaseous flow channel. Gas well production may halts when sulfur deposition became severe. In this paper, an integrated forecast model of sulfur deposition in high sulfur gas well is presented by coupling pressure and temperature forecasting model, critical sustaining velocity model of particle and model of solubility ofsulfur particles in gas phase. A case analysis is carried out in well-L. The result shows that, with production decrease,gaseous velocity gradually declines, and therefore, area of sulfur deposition steps up along borehole after productiondeclines to critical production.