Abstract:

Molecular distillation has the characteristics of high vacuum, low pressure drop, high-efficiency of heat and mass transfer, and has advantages in separating high viscosity, high boiling point, and thermal sensitive feed. The feasibility of molecular distillation for separating N4016 and 150BS mixture is proved by experiments, and the effect of temperature, pressure, feed flow on the yield of light components is explored. Through the analysis and comparison of product properties, it is found that molecular distillation has poor selectivity for distillation range, but has strong selectivity for viscosity compared with vacuum tray distillation. Molecular distillation is beneficial to improve the viscosity and pour point of 150BS, but the viscosity index decreases slightly, and the total yield of 150BS can be increased.

Key words: molecular distillation, 150BS, bright stock, yield of light components, yield of heavy components, molecular free path

摘要：

短程蒸馏具有真空度高、压力降小、传热和传质效率高的特点，在分离高黏度、高沸点、热敏性物料方面有独特的优势。通过实验证明了短程蒸馏可用于分离N4016橡胶增塑剂和150BS光亮油的混合物料，并探索了操作温度、压力、进料量3个因素对轻组分收率的影响。通过产品性质分析和对比发现，与常规减压塔板分离相比，短程蒸馏对馏程选择性较差，但对黏度有极强的选择性。短程蒸馏有利于改善150BS黏度和倾点，但黏度指数略下降，150BS总收率有所提高。

关键词: 短程蒸馏, 150BS, 光亮油, 轻组分收率, 重组分收率, 分子自由程