《化工原理课程设计》板式精馏塔设计报告.pdf

该【《化工原理课程设计》板式精馏塔设计报告 】是由【1781111****】上传分享，beplayapp体育下载一共【43】页，该beplayapp体育下载可以免费在线阅读，需要了解更多关于【《化工原理课程设计》板式精馏塔设计报告 】的内容，可以使用beplayapp体育下载的站内搜索功能，选择自己适合的beplayapp体育下载，以下文字是截取该文章内的部分文字，如需要获得完整电子版，请下载此beplayapp体育下载到您的设备，方便您编辑和打印。:..word完美格式《化工原理课程设计》报告4万吨/年甲醇~水板式精馏塔设计精心整理学****帮手:..word完美格式目录一、概述···························································································错误!未定义书签。·································错误!未定义书签。············································5二:计算过程····································································································································································································································································································································································································错误!未定义书签。、釜残液量及加热蒸汽量的计算错误!未定义书签。····························································错误!未定义书签。··························································错误!未定义书签。·······················错误!未定义书签。······················错误!未定义书签。·············错误!未定义书签。························································································································································································································································································错误!未定义书签。·························································································错误!未定义书签。·······································31精心整理学****帮手:..···········································································································································································(单板压降)h·········································································································34?········································································································································································································································································································································································································································································································································································································································································································41精心整理学****帮手:..word完美格式一、、炼油生产中最重要的设备之一。塔设备的设计和研究,已经受到化工行业的极大重视。在化工生产中,塔设备的性能对于整个装置的产品产量、质量、生产能力和消耗定额,以及三废处理和环境保护等各个方面,都有非常重大的影响。精馏过程的实质是利用混合物中各组分具有不同的挥发度。即在同一温度下,各组分的饱和蒸汽压不同这一性质,使液相中的轻组分转移到汽相中,汽相中的重组分转移到液相中,从而达到分离的目的。因此精馏塔操作弹性的好坏直接关系到石油化工企业的经济效益。为了加强工业技术的竞争力,长期以来,各国都在加大塔的研究力度。如今在我国常用的板式塔中主要为泡罩塔、浮阀塔、筛板塔和舌型塔等。填料种类出拉西、环鲍尔环外,阶梯环以及波纹填料、金属丝网填料等规整填料也常采用。更加强了对筛板塔的研究,提出了斜空塔和浮动喷射塔等新塔型。同时我国还进口一些新型塔设备,这些设备的引进也带动了我国自己的塔设备的科研、设计工作,加速了我国塔技术的开发。精心整理学****帮手:..word完美格式国外关于塔的研究如今已经放慢了脚步,是因为已经研究出了塔盘的效率并不取决与塔盘的结构,而是主要取决与物系的性质,如:挥发度、黏度、混合物的组分等。国外已经转向研究“在提高处理能力和简化结构的前提下,保持适当的操作弹性和压力降,并尽量提高塔盘的效率。”在新型填料方面则在努力的研究发展有利于气液分布均匀、高效和制造方便的填料。经过我国这些年的努力,在塔研究方面与国外先进技术的差距正在不断的减小目前,精馏塔的设计方法以严格计算为主,也有一些简化的模型,但是严格计算法对于连续精馏塔是最常采用的,我们此次所做的计算也采用严格计算法。:甲醇、水原料温度:泡点进料处理量:4万吨/年原料组成:甲醇的质量分率w=(质量分数)f产品要求:塔顶甲醇的质量分率w=(质量分数),塔底甲醇质量分率d=(质量分数)生产时间:300天/年冷却水进口温度:25℃加热剂::..word完美格式单板压降::连续操作,泡点回流全塔效率:Et=50%(包括操作压强、进料状态、加热剂、冷却剂、回流比)(1)全塔物料衡算(2)最佳回流比的确定精心整理学****帮手:..word完美格式(3)理论板及实际板的确定(4)塔径的计算(5)降液管及溢流堰尺寸的确定(6)浮阀数及排列方式(筛板孔径及排列方式)的确定(7)塔板流动性能的校核(液沫夹带校核,塔板阻力校核,降液管液泛校核,液体在降液管内停留时间校核,严重漏液校核)(8)塔板负荷性能图的绘制(9)(1)换热器的面积计算及选型(2)各种接管管径的计算及选型(3):(包括塔盘、裙座、进出口料管)二:,若按年工作日300天,每天开动设备24小时计算,由于产品粘度较小,流量较大,为减少造价,降低生产过程中压降和塔板液面落差的影响,精心整理学****帮手:..word完美格式提高生产效率,选用浮阀塔。??105(Pa),但是饱和液体进料时进料温度不受季节、气温变化和前段工序波动的影响,塔的操作比较容易控制;此外,饱和液体进料时精馏段和提馏段的塔径相同,无论是设计计算还是实际加工制造这样的精馏塔都比较容易,为此,本次设计中采取饱和液体进料(q=1)。;由于乙醇~水体系中,乙醇是轻组分,水由塔底排出,且水的比热较大,故可采用直接水蒸气加热,这时只需在塔底安装一个鼓泡管,于是可省去一个再沸器,并且可以利用压力较底的蒸汽进行加热,无论是设备费用还是操作费用都可以降低。:..word完美格式精馏过程的原理是多次部分冷凝和多次部分汽化。因此热效率较低,通常进入再沸器的能量只有5%左右可以被有效利用。虽然塔顶蒸汽冷凝可以放出大量热量,但是由于其位能较低,不可能直接用作为塔底的热源。为此,我们拟采用塔釜残液对原料液进行加热。,需先把设计要求中的质量分数转化为摩尔分数。原料液的摩尔组成:甲醇的摩尔质量为:32kg/kmol水的摩尔质量为:18kg/???/32x???(1?)/???(1?)/18以年工作日为300天,每天开车24小时计,进料量为:进料液的平均摩尔数精心整理学****帮手:..M32??18?(1?0..23)??107F????24?300Fx?????x???:F?D?W求得W?、馏出液与釜残液的流量名称原料液馏出液釜残液w(质量分数)(摩尔分数).(图3-1)查得塔顶、塔底温度精心整理学****帮手:..12—液相图3-1甲醇-水的等压曲线或用计算法求得:①塔顶:,P???假设t=83℃,利用安托因方程,At???Bt??,Po??PoPox再利用x?B,y?APo?PoPAB求得x?,y?:..,Po?℃,同理求得ABx'?,y'?:t???,则t?℃83???,Po?=℃时,??A??②塔进料处:x??,Po?=90℃,同理求得ABx?=91Po?,Po?56kpa℃,同理求得ABx'?:t???,则t?℃91???,Po?=℃时,??A??:..③?,Po?=108℃,同理求得ABx?=109Po?,Po?℃,同理求得ABx'?:t?109℃3当t=109℃时,??A???????????(q=1),x?x??x相平衡方程y?1?(??1)x当x?x,求出夹紧点x?,y?,因此:FPPx???DP????:..(?2)Rmin最少理论板数N的确定:利用芬斯克方程min??x??1?x?????????lg??D??W??lg???????1?x??x??1?????DW???N????(R+1)有直接的关系,因此绘制N(R+1)~R图就可以求当R值时N(R+1)最小的为实际RR令??,由不同β得到R值RminN?NR?R利用吉利兰图min~min求出N值,进而能得到N(R+1)N?1R?1吉利兰图精心整理学****帮手:..β=、、、、、、、、2,将查上图或计算出相应的值,见下表:?1N??(R+1):..??1N??(R+1)?R验算:若min?,可以用下公式:R?1N?N?R?R?lgmin???min???1?R?1?①若R=,则R?,利用公式minN?N?R?R?N?Nlgmin???min???,则N?,求得N?1?R?1?N?1N?R?1??。N?N?R?R?②若R=,利用公式lgmin???min???1?R?1?N?Nmin?,则N?,求得N?R?1???1N?N?R?R?N?N③若R=,利用公式lgmin???min???,N?1?R?1?N?1则N?,求得N?R?1??。R?R计算结果表明在R=(~)范围内min?,但N?R?1?值确随RR?1精心整理学****帮手:..word完美格式值增大而减小,无最小值,所以根据作图找到最适回流比R=(~).取R=①精馏段操作方程:?x?D?x????1R?:L?RD???:V??R?1?D???②提馏段操作方程:L'?L?qF???:气体的摩尔流量:V'?V??q?1?F??0?'??x?W?x???'V':x?:..:y??:y??:x?x??:y??1????1?x1?:y?x?????相平衡方程?x?????x?????x?????x?????x?????x?515?x?(进料板)66Fy????x?????x?????x?:..word完美格式y????x?????x?????x?????x??x??13块(含塔釜)理其中,第6块为进料板。NE?理?52%由条件知全塔效率tN实N13N?理??25则可计算出实际塔板层数(含塔釜)~甲苯系的相平衡数据可以查得:y?x??(塔顶第一块板)1D1y??(加料板)FFx??(塔釜)ww全塔的相对平均挥发度:?????????:精心整理学****帮手:..word完美格式t?t???109t?DFW??(见下页),由表中数据可知:表3精馏段的已知数据位置进料板塔顶(第一块板)x'?'?x'?'?'???x???????/℃①液相平均摩尔质量:M???LFL1????:t?FD??:..word完美格式在平均温度下查得??807kg/m3,??:1x'1?x'?Lm?Lm???Lm苯甲苯x'?x'?,平均质量分数x'?F1??,????????②汽相平均摩尔质量:M???VFV1????N?:PM??VmRT其中,平均压强P????6??1F??,???:..?????。表4精馏段的汽液相负荷名称液相汽相平均摩尔质量/kg/.78m3/(()),采用与精馏段相同的计算方法可以得到提馏段的负荷,结果列于表6。表5提馏段的已知数据位置塔釜进料板x'?'?'?'?:..word完美格式x????????/℃①液相平均摩尔质量:M???LFL2????109平均温度:t?FD????797kg/m3,??:1x'1?x'?Lm?Lm???Lm苯甲苯x'?x'?,平均质量分数x'?F2???'?,Lm提馏段的液相负荷L'?'?'????②汽相平均摩尔质量:M???VFV2??:..word完美格式汽相平均密度为:PM??VmRT平均压强P??13???6??2F???'?,Vm提馏段的汽相负荷V'?'?'????.582平均密度/kg/((),为便于制造,我们取两段的塔径相等。有以上的计算结果可以知道:汽塔的平均蒸汽流量:精心整理学****帮手:..word完美格式(V?V')??nn???:(L?L')??nn???:???'???VmVm??:???'???LmLm??:4VD?S?u由于适宜的空塔气速u?(~)u,因此,需先计算出最大允许气速u。maxmax???u?CLVmax?V初步设定板间距H??:F?()L???:..?,由于C?C(),需先求平均表面张力:202020t?t???109全塔的平均温度:t?DFW???,平均摩尔分数为?《化工原理》书379页液体表面张力共线图并计算出液体表面张力????20mN/m2的物系绘制的,若所处物系的表?面张力为其他值,则需按式C?C(),即:??()?:..????CV????=~)u=(~)m/smax则取适宜的空塔气速u?:①精馏段:气相流量V????n???u??②提馏段:气相流量V'??'4?'?n???u???,所以采用单溢流型分块式塔板。:..l,而l/D()W所以l?(~),取l??