共查询到17条相似文献,搜索用时 203 毫秒
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《化工进展》2017,(10)
提出双储罐替代的恒全回流半连续精馏操作方式(SCTR),该操作方式中塔顶和塔釜的双储罐分别交替使用,使精馏塔处于恒全回流状态,并能进行半连续地产品采出和原料补充。通过Matlab编程进行模拟,以轻重组分回收率、单位时间总产量(P.I.)等作为指标,在不同进料情况下对各参数的优化,包括储罐总体积、各储罐体积等。模拟结果表明,SCTR操作方式与恒回流比间歇精馏操作方式相比,最多可节省操作时间32%,与塔顶单储罐动态累积循环全回流间歇精馏相比,操作时间相近,与多储罐动态累积循环全回流间歇精馏操作方式相比,耗时略高。适用于轻组分浓度低的二元组分的分离。采用乙醇/正丙醇物系验证了该操作方式在进料浓度分别为0.2、0.5和0.8情况下的可行性和操作的简单灵活。 相似文献
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多储罐动态全回流分离方法 总被引:1,自引:1,他引:0
多储罐间歇精馏是新型操作方式,目前仅用于多组分混合物分离.为了扩大多储罐间歇精馏塔的应用,将其用于2组分物系的分离,提出了多储罐动态全回流分离方法.其特点是可分为全回流提浓和倒罐采出阶段,这2个阶段交替进行,直到分离结束.建立了该过程的数学模型,并与常规恒回流比方式比较,结果表明:动态全回流方法省时.进一步通过乙酸-水... 相似文献
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提出了通过塔顶、塔中上以及塔中3个温度控制进行操作状态转换的无累积罐循环全回流间歇精馏控制方法,并以理想物系--乙醇-正丙醇混合物为分离物系进行了实验研究。通过实验确定了温度控制条件为当塔顶温度稳定后且塔顶和塔中上温差为0.3 ℃时变全回流为全采出操作,当塔中温度升高1.0 ℃时停止全采出转为全回流操作。同时还考察了在不同乙醇投料浓度条件下这种操作的运行情况,发现不同投料浓度对塔顶产品平均纯度的影响并不显著,基本能保持在0.99。最后在相同的投料浓度和操作条件下,对比了这种新型控制方式和双温度控制方式,结果表明三温度控制方式比双温度控制方式操作时间减少了23.3 min,分离效率提高了23.95%,产品浓度提高了1.06%,产品收率提高了1.08%。 相似文献
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提出了一种过程始终为全回流操作的间歇精馏新型操作方式,其特征在于沿塔身不同高度设置有多个中间累积罐,操作中整塔始终处于全回流状态,每隔一段时间将下一级储罐内的液体转移至上一级储罐,塔顶储罐内液体作为产品转移到产品储槽。建立了该流程的数学模型并采用Matlab软件进行模拟,当目标产品浓度相同时,新操作方式的可以节省操作时间,在最优化的中间累计罐密集程度下,可节省50%左右,与具体操作参数相关;最后采用乙酸-水二元物系对该操作方式进行了试验验证,且整塔运行稳定易于操作控制。 相似文献
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间歇精馏模拟及操作方式的研究进展 总被引:2,自引:0,他引:2
综述了间歇精馏模拟研究常用的数学模型,主要介绍了严格模型和简捷模型,简要讨论了各个模型的特点.较详细地介绍了国内外间歇精馏操作方式的研究进展,讨论了动态累积间歇精馏塔、反向间歇精馏塔、中间罐间歇精馏塔、多罐间歇精馏塔等新塔型的操作. 相似文献
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鉴于间歇精馏热力学效率低的缺点,提出带有内部热集成的多储罐间歇精馏全回流操作(IHIMVBD)分离二元混合物的新型操作方式。在该操作中,多储罐间歇精馏塔被同轴的夹套式再沸器环绕,利用安装在再沸蒸汽管线上的压缩机使精馏塔的操作压力高于夹套式再沸器,使热量通过精馏塔壁面从高压的精馏塔传向低压的再沸器,实现热量的内部集成。为了进一步提高热力学效率和经济效益,将塔顶蒸汽再压缩技术应用于IHIMVBD,构成强化的内部热集成多储罐间歇精馏全回流操作(Int-IHIMVBD)。该操作能额外利用被压缩的塔顶蒸汽的潜热供给塔釜料液再沸,实现塔顶蒸汽与塔釜料液的热集成。通过模拟分离乙醇-正丙醇的实例表明,相比MVBD和IHIMVBD,Int-IHIMVBD能显著提高分离过程的热力学效率和经济效益。 相似文献
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基于恒摩尔流和正规溶液理论建立了O_2-Kr-Xe间歇精馏塔模型,应用BRK法求得各操作条件和返复全回流式操作方式对组分回收率的影响,表明塔板数、上升气量和回流比的增加以及合适的板上持液量都有利精馏操作,通过返复全回流式操作可提高组分的回收率。 相似文献
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基于恒摩尔流和正规溶液理论建立了O_2-Kr-Xe间歇精馏塔模型,应用BRK法求得各操作条件和返复全回流式操作方式对组分回收率的影响,表明塔板数、上升气量和回流比的增加以及合适的板上持液量都有利精馏操作,通过返复全回流式操作可提高组分的回收率。 相似文献
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Cyclic total reflux batch distillation with two reflux drums 总被引:1,自引:0,他引:1
The present work proposes a novel cyclic total reflux (CTR) operation of batch distillation with two reflux drums working alternatively. A mathematical model is set up for the process. The computational comparison of the novel policy with the regular constant reflux and non-cyclic total reflux (NCTR) operations is also presented. The experimental runs of the new mode show that it can be operated and controlled more easily. The novel operation is significantly time saving compared to the mode of regular constant reflux theoretically and experimentally. The two reflux drum mode of CTR is also suitable for the separation of the mixture containing a large amount of light component. 相似文献
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Cyclic total reflux (CTR) batch distillation is a promising mode of the process but lacking of appropriate modeling for the period of filling the reflux drum. A new dynamic modeling method for the simulation of CTR batch distillation is proposed in this work, in which the changes in column holdup and liquid flow rate during the filling of the drum, and the consequent change in valid number of theoretical plates are considered. The effect of drum holdup on operation time is investigated and the optimal drum holdup is obtained from the simulation. The dynamic modeling is compared to the conventional modeling without consideration of change in liquid flow rate. The experimental result shows that the present modeling is more reliable and more accurate, especially for the col-umn with large liquid holdup. 相似文献
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Multivessel batch distillation (MVBD) is mainly used to separate mixtures with more than two compo-nents. In this article, a new operation mode with MVBD is proposed for separation of binary mixtures under total reflux. A mathematic model is setup for the simulation. The proposed operation policy and the regular operation with constant reflux are compared theoretically and experimentally. The results show that the new operation mode has great advantages in time saving and operation flexibility. MVBD presents great potential for separation with high efficiency. 相似文献
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The total withdrawal operation is an inevitable section in cyclic total reflux batch distillation.In the operation,an interesting phenomenon "overhead concentration platform"(OCP) appears,which is defined as a period of time with high overhead concentrations when the operation is changed from total reflux to total withdrawal.The OCP phenomenon and its influential factors,such as the theoretical stage number,feed concentration,and feed composition,are examined by simulations and experiments.The experimental equipment is a column with random packings.It is shown that the number of theoretical stages influences the OCP more significantly than the other factors. 相似文献