高速非达西流动时元素硫沉积模型研究

元素硫沉积是含硫气藏开发过程中广泛存在而又必须解决的难题之一。高含硫气藏一旦投入开发，地层压力会逐步下降，使得元素硫溶解度下降而沉积下来，沉积的元素硫会堵塞地层孔隙，降低渗流通道，影响气井产能。考虑了高含硫气体在近井地带作高速非达西流动，建立了硫的沉积模型，并利用该模型对实际气藏进行预测和对比研究，再通过实例计算发现，硫非瞬时平衡沉积比瞬时平衡沉积对地层的伤害更严重，高速非达西流动沉积比达西流动时对地层伤害更严重，认为在开发高含硫气藏时，必须合理选择开发速度，有效防止元素硫沉积。

THE MODEL STUDY ON THE ELEMENTAL SULFUR DEPOSITION CONSIDERING HIGH VELOCITY NON-DARCY FLOW

The deposition of elemental sulfur belongs to one of the difficult tasks when developing the high sulfur content gas reservoirs which exist extensively. The solubility of elemental sulfur will be reduced when the pressure decreases. The reduction of elemental sulfur solubility leads to sulfur depositions, which damages the formation and depress the porosity and permeability. The results of sulfur deposition depress the gas production. Based on the high velocity non-Darcy flow near the well bore, the model of elemental sulfur deposition is established firstly, then used to calculate the real gas reservoirs comparing to the Darcy flow. By comparison, the results show that the amount of the non-equilibrium deposition is more than the equilibrium deposition and the damage caused by the non-Darcy flow is more than that by the Darcy flow. So a reasonable production rate is required to choose in order to prevent the sulfur from deposition when developing the gas reservoirs with high sulfur content.