刮膜式分子蒸馏技术精制山茶油的数值模拟

Numerical simulation of camellia oil refining by wiped film molecular distillation

山茶油是一种具有高附加值、丰富保健功能的天然产品。由于目前山茶油的深加工技术尚不完善,采用的化学精炼工艺脱除山茶油中游离脂肪酸时存在皂脚等物质残留问题,难以达到国家标准(GB/T11765-2018)的要求。刮膜式分子蒸馏技术独特的动态膜温和蒸发过程,在精细化工分离与提纯中占据着绝对的优势。为了获得最佳的山茶油分离参数与分离机理,文中采用CFD方法对刮膜式分子蒸馏技术精制山茶油的过程进行数值模拟,结果表明:蒸发器内液膜分布和传热系数变化受转子转速和进料速度影响较大;当蒸发温度为190℃、刮膜器转速为300 r/min、进料速度为900 g/h时系统的综合指标为最佳,该模拟结果对分子蒸馏精制山茶油的工艺优化及工艺参数控制具有较好的参考价值。

Camellia oil is a natural product with high added value and rich health care functions.Due to the current deep processing technology of camellia oil is not yet perfect,the chemical refining process used to remove free fatty acids in the camellia oil has the residue of substances such as soap foot,which is difficult to meet the requirements of the national standard(GB/T11765-2018).The unique dynamic membrane mild evaporation process of wiped film molecular distillation is an absolute advantage in the separation and purification of fine chemical industry.In order to obtain the best separation parameters and mechanism of camellia oil,the process of refining camellia oil by wiped film molecular distillation was simulated by CFD method.The results show that the distribution of liquid film and the change of heat transfer coefficient in the evaporator are greatly affected by rotor speed and feed speed.When the evaporation temperature is 190℃,the speed of the film scraper is 300 r/min,and the feed speed is 900 g/h,the comprehensive index of the system is the best.The simulation results have a good reference value for the process optimization and process parameter control of molecular distillation of refined camellia oil.