高含硫气井井筒硫沉积预测

Prediction of sulfur deposition in wellbore of high sulfur gas well

随着高含硫气藏的开发,析出的硫会对储层造成伤害,影响气井的正常生产,因此,准确预测硫的沉积对酸性气田的合理高效开发具有十分重要的意义。文中根据气、液、固三相流动规律,建立了高温高压高含硫气井井筒硫沉积预测模型,利用缔合模型的基本原理,建立包含温度、压力和流态3个变量的硫溶解度函数模型,用来预测硫在井筒中的析出位置;再利用缔合模型的相关理论解释硫元素在井筒中的溶解机理,以温度、压力和硫溶解度为变量,判断单质硫是否沉积、沉积位置,并对沉积量进行动态计算。以普光气田×井为例,计算得出硫溶解度和析出量随井筒的变化规律,其结果与实际情况吻合较好。

With the development process of high sulfur gas reservoir, the sulfur deposited will damage to formation and the sulfur deposition in wellhore will affect the normal production of gas well. Therefore, the accurate prediction of sulfur deposition has very important significance for the reasonable and efficient development of sour gas field. According to the three-phase flow law of gas, liquid and solid, the prediction model of sulfur deposition in wellbore is established for the high sulfur gas well with high temperature and high pressure. Using the basal principle of coupling model, the sulfur solubility function model is huih, including three variables such as temperature, pressure and flow condition. This model can be used to predict sulfur precipitation location in well. The correlation theory of association model is used to interpret the dissolution mechanism of sulfur in wellbore and the sulfur deposition position and deposition quantity are simulated taking the temperature, pressure and solubility as variables. Finally, taking one well in Puguang Gas Field as an example, the change law of sulfur solubility and precipitation amount as wellbore is calculated, having a good matching with the actual result.