曹学文,杨文,马玉鹏,郭悠悠

• 1:中国石油大学(华东)储运与建筑工程学院
• 2:中国石油工程建设公司北京设计分公司
• 3:中国石油天然气股份有限公司北京油气调控中心

摘要(Abstract)：

在油气输送过程中,随着热力学条件发生变化,体系中的蜡组分将析出并沉积于管壁上,对管道输送过程造成一定的阻碍,且在深水高压低温条件下的输送体系中尤为突出。采用状态方程结合UNIQUAC模型建立了多相体系中蜡晶析出热力学模型,模型建立过程中考虑到液相描述一致性、固-固转变、纯组分热力学性质、Poynting修正项处理以及活度系数计算等问题。对于模型预测计算过程中涉及到的轻组分与重组分(以C20进行划分)间二元交互系数这一重要参数,采用气-液平衡及液-固平衡数据进行反算,取为-0.0296。运用该模型对六组混合物体系进行析蜡点计算,计算结果表明:析蜡点随压力的变化趋势与实验结果一致,计算结果与实验数据绝对误差在2.40 K以内,相对误差在0.77%以内,取得了较好的预测效果。

关键词(KeyWords)： 多相体系;蜡;热力学模型;相平衡

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51274232);国家自然科学基金青年基金(51406240)

作者(Author): 曹学文,杨文,马玉鹏,郭悠悠

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