辽河减压渣油-正戊烷体系的相态变化特性

利用RUSKA公司无汞PVT装置,对辽河减压渣油-正戊烷体系的相行为进行了实验观察,测定了辽河渣油-正戊烷体系相态变化的边界线,如液-液相分界线、液-液-气三相区分界线等,绘制了体系的p-t相图;在140℃～190℃,1.0MPa～10.0MPa,溶剂质量比为3.0～6.0的条件下,对体系相特性的变化进行了分析和讨论。在实验条件下,辽河渣油-戊烷体系的p-t相图可以划分为四个区域:单一液相区、液-液两相区、液-液-气三相区、气-液两相区;溶剂质量比对由单一液相区转变为液-液两相分相压力的影响显著,溶剂质量比越大,分相压力越大;但溶剂质量比对液-液-气三相区影响不大。确定了辽河渣油-正戊烷体系溶剂脱沥青过程适宜的操作区域。

Phase characteristics of Liaohe vacuum residue - pentane system

The phase behavior of Liaohe vacuum residue － n-pentane system was investigated with visual observation in a set of Hg-free PVT equipment with two cells and a sight window designated by RUSKA Co. Based on the observation, the p-t phase diagrams with the verging lines of phase transition such as liquid-liquid and liquid-liquid-vapor regions were protracted. The phase characteristics for such system were discussed at 140℃～190℃, 1.0MPa～10.0MPa and the mass ratio of solvent to oil (m_s/m_o) of 3.0~6.0. Under the experimental conditions, the p-t phase diagram is divided into four regions of single liquid, liquid-liquid, liquid-liquid-vapor and liquid-vapor. The phase transition pressures from single liquid to liquid-liquid region are obviously affected by the m_s/m_o ratio; the phase transition pressure increases with the m_s/m_o ratio. However, the m_s/m_o ratio exhibits little effect on the range of liquid-liquid-vapor region. Based on these results, the operating region suitable for the Liaohe vacuum residue － n-pentane deasphalting process was determined.