预测凝析油气体系蜡沉积热力学模型

THERMODYNAMIC MODEL OF PREDICTING WAX PRECIPITATION IN CONDENSATE-GAS SYSTEM

根据实验研究结果 ,提出了一个预测凝析油气体系蜡沉积的热力学模型。该模型把蜡沉积视为多固相过程 ,沉积出的蜡由几个固相组成 ,每一个固相都由一个拟组分表示 ,固相之间彼此互不混合。根据这一认识 ,文章提出了气液多固相物料平衡方程 ,用考虑固相沉积的多相闪蒸数值算法 ,模型能对析蜡量进行量化模拟计算。模型中气液相参数通过状态方程计算获得。通过对凝析油蜡沉积的计算表明 ,用该模型计算的蜡的沉积量和析蜡温度与实验结果非常吻合。

According to the experimental results, a thermodynamic model of predicting wax precipitation in condensate-gas system is proposed in the paper. This model takes the wax precipitation as a multiple solid phase precipitating process,the wax precipitated being composed of several solid phases teach solid phase is indicated as a pseudocomponent; and the solid phases don't mix with each other. In light of such a thought,a gas-liquid multiple solid phase material balance equation is put forward in the paper. The amount of wax precipitation can be simulatively calculated by the model by use of the multiple phase flash numerical algorithm in consideration of solid precipitation. The gas and liquid phase parameters in the modle may be obtained through calculating by applying state equation. The calculated results indicated that the model-calculated amount of wax precipitation and the model-calculated cloud-point temperatures were well identical with the experimental results.