利用超临界流体萃取技术，从机械压榨后的饼渣中回收剩余特种油料

Recovery of residual specialty oils after mechanical press using supercritical fluid extraction

通过机械压榨的方法从种子中获取特种油料，饼渣中的剩余油含量在5-15wt．％，这意味着机械压榨法将1／3的可溶性原油馏分留在了饼渣中。超临界流体萃取则为从饼渣中回收这些剩余油提供了一种“无溶剂（在萃取中不使用任何有机溶剂）”的途径。超临界二氧化碳萃取后，油的残留量小于0．6wt．％（即回收率高于95wt．％）。本文以压榨后的亚麻籽饼渣为例，阐述对剩余油料的回收。萃取产量和品质将作为压力（80—600bar）、温度（40℃～80℃）和溶剂／进料比率的函数加以讨论，还将谈及工艺设计和经济意义。

Specialty oils are processed by mechanical pressing of seeds. The residual oil content in the cake ranges from 5 to 15 wt %, which means that the mechanical pressing method leaves up to 1/3 of the original oil-soluble fraction in the cake. Supercritical fluid extraction provides a solvent-free method for recovering residual oils from the cake. The residual amount of oil after supercfitical carbon dioxide extraction is less than 0.6 wt. % （ i. e. an oil recovery higher than 95 wt % ） . In this presentation the recovery of residual oil from flax seed cake after pressing will be used as an example. Extraction yields and quality of the oil as a function of pressure （ 80 - 600 bar）, temperature （40 - 80℃） and solvent/feed ratio will be discussed, as will design and economics also.