炼油厂燃料气回收液化气过程的设计与控制研究

以某炼油厂燃料气回收液化气(LPG)为对象,分别对3种LPG回收流程进行了研究。在稳态模拟的基础上,以年总费用为优化目标,优化了各流程的主要工艺参数。结果表明,隔壁塔流程较另外两种流程的年总费用分别降低37.66%和11.35%,表现出较大的经济优势。此外,对炼油厂燃料气回收LPG隔壁塔流程的动态特性进行了研究,提出的四点温度控制结构能够有效地抵抗进料扰动,具有良好的可控性。由此可见,隔壁塔在炼油厂燃料气回收LPG工艺中具有非常高的应用潜力。

Design, Optimization and Control of Extractive Distillation for Separation of Ethyl Acetate-Ethanol-Water Mixture Using Ionic Liquids

In this work, the process simulation of pressure-swing distillation(PSD) and extractive distillation(ED) using ionic liquid(IL) 1-butyl-3-methylimidazolium acetate([bmim][OAc]) as the entrainer for separation of ethyl acetateethanol-water mixture is performed. The design parameters of the two distillation processes are optimized with the minimum total annual cost(TAC) serving as the objective function. The results show that the TAC saving of ED process is 35.27% in comparison with that of PSD process in the case of achieving the same purity and yield of ethyl acetate.In addition, the dynamic controllability of ED process is further studied. The traditional two-point temperature control structure is proposed for the ED process, and it works pretty well while taking into account the disturbances in both feed rate and feed composition.

中链脂肪酸对高脂饲料诱导的肥胖大鼠高密度脂蛋白的调节作用

目的观察中链脂肪酸(MCFA)对高脂饲料诱导的肥胖SD大鼠高密度脂蛋白的代谢调节作用,探讨MCFA降低血胆固醇的可能机制。方法高脂饲料诱导SD大鼠肥胖,30只肥胖大鼠按空腹体重随机分为3组,每组10只,分别给予含2%(2 g/100 g)辛酸(C8∶0)、癸酸(C10∶0)和油酸(C18∶1)的高脂饲料喂养8周,于4周和8周时取眼底静脉丛血,测定血清甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-c)、低密度脂蛋白胆固醇(LDL-c)、高密度脂蛋白(HDL)、载脂蛋白A1(ApoA1)、载脂蛋白A2(ApoA2)浓度,于8周时取大鼠肝脏和小肠,ELISA法测定HDL、ApoA1、ApoA2含量,Real-time PCR法测定Apo A1及ApoA2 mRNA表达量。结果中链脂肪酸喂养肥胖大鼠4周时,3组大鼠血清血脂水平无差异,8周时,辛酸组和癸酸组血清TG、TC水平均显著低于4周时(P<0.05),且显著低于油酸组(P<0.05),HDL水平显著高于油酸组(P<0.05)。HDL-c/LDL-c比值以辛酸组最高,且显著高于油酸组(P<0.05)。8周时,大鼠小肠中HDL、ApoA1浓度及mRNA表达量也以辛酸组最高,显著高于油酸组(P<0.05),但与癸酸组比较差异无统计学意义。大鼠肝脏中各项指标组间差异均无统计学意义。结论中链脂肪酸可能通过增加小肠HDL及ApoA1表达,上调HDL水平及HDL-c/LDL-c比值,降低肥胖大鼠血胆固醇水平。