水蒸汽加熱苯甲苯混合液臥式列管換熱器的設(shè)計(jì)[1]

1、rehabilitation training, because at that time the city has not specifically for deaf children of professional rehabilitation agencies, she will accept rehabilitation training must go to suzhou, due to her age is too small must take care of their parents, her mother had to resign to suzhou to take ca

2、re of her, thus to their family brought two problems, one is the economic pressure, second, children are in the most need caring parents feel term age and father separated, unable to feel the happy family to grow. in order to avoid more and more families appear this kind of circumstance, actively co

3、ordinating the city fimitic established rehabilitation center, operation center for the xx membership received rehabilitation training of special children and parents brought great convenience, to enable them to the nearest and handy to get high-quality rehabilitation services, huimin policy of the

4、communist party of china has been fully reflected.regular organization of the fast forward, three special children into society. due to the special childrens own disability, they rarely and social contact, we hope that in their rehabilitation training can have more opportunities to integrate into so

5、ciety, by the municipal cdpf coordination has been relevant departments of the strong support, promote the special children into social work: one is the municipal cdpf and city bureau of education in training children rehabilitation assessment, 2015 years 3 hearing-impaired children get a rehabilita

6、tion of the good results, enter the ordinary kindergarten and primary school; the second is the city library volunteer monthly to center on childrens stories, playing games and other entertainment activities, into a step broaden their way of thinking; the third is under the support of the city board

7、 of education, the center will and yanshan mountain kindergarten cooperation, fusion education project weekly by the special education teacher lead 1-2 hearing-impaired children into yanshan mountain kindergarten accept half a day of kindergarten education, let children with special filling feeling

8、kindergarten learning atmosphere, for their future access to kindergarten and primary school lay a solid foundation., handicap love, care for children with special. caring for children with special needs to let them with healthy children as happy growth but also our work direction: one is actively c

9、ontact the society from all walks of life of the difficulties children with special care and support this year in coordination with the city fimitic, ningbo bank co., ltd. xx branch president assistant zhao yi for a row represents dandelion love fund to in the center received rehabilitation training

10、 of xu yang and xu miao brother and sister to send two of the loving enterprises special care; the second is actively contact the love team and community volunteers to the children in the center to all kinds of theatrical performances and interactive games, let them enjoy the happiness in the activi

11、ties, and further enrich the their spiritual and cultural life.five, increase the propaganda of rehabilitation services, and further enhance the sense of rehabilitation. in the suburbs especially in rural areas, to disabled學(xué) 號(hào) 0120920400335課程設(shè)計(jì) 題 目水蒸汽加熱苯-甲苯混合液臥式列管換熱器的設(shè)計(jì) 學(xué) 院 化學(xué)工程學(xué)院 專業(yè)班級(jí) 制藥0903 姓 名 指導(dǎo)

12、老師 2011年 8月課程設(shè)計(jì)任務(wù)書學(xué)生姓名： 劉麗娜 專業(yè)班級(jí)： 制藥0903班 指導(dǎo)教師： 工作單位： 化學(xué)工程學(xué)院 題 目: 水蒸汽加熱苯-甲苯混合液臥式列管換熱器的設(shè)計(jì) 初始條件：設(shè)計(jì)一臺(tái)臥式列管換熱器，將質(zhì)量流量為80噸/小時(shí)的苯-甲苯（x1=0.4）混合液從20加熱到94，加熱介質(zhì)采用300kpa絕壓的飽和水蒸汽，冷凝液在飽和溫度下排出，要求換熱器的管程壓降小于70kpa。要求完成的主要任務(wù): （包括課程設(shè)計(jì)工作量及其技術(shù)要求，以及說明書撰寫等具體要求）1、合理的參數(shù)選擇和結(jié)構(gòu)設(shè)計(jì)；2、工藝計(jì)算，包括傳熱計(jì)算和壓降計(jì)算等；3、主要設(shè)備工藝尺寸設(shè)計(jì)。時(shí)間安排：設(shè) 計(jì) 內(nèi) 容所用時(shí)間1

13、、根據(jù)換熱任務(wù)和有關(guān)要求確定設(shè)計(jì)方案；1天2、初步確定換熱器的結(jié)構(gòu)和尺寸； 1天3、核算換熱器的傳熱面積和流體阻力；1天4、確定換熱器的工藝結(jié)構(gòu)；1天5、寫出設(shè)計(jì)說明書。1天指導(dǎo)教師簽名： 年 月 日系主任（或責(zé)任教師）簽名： 年 月 日目錄設(shè)計(jì)任務(wù)書2緒論4符號(hào)說明7工藝計(jì)算8 確定物性數(shù)據(jù)8 確定計(jì)劃方案9 計(jì)算總傳熱面積9 工藝結(jié)構(gòu)尺寸10 換熱器核算10設(shè)計(jì)數(shù)據(jù)結(jié)果一覽表15結(jié)束語16參考文獻(xiàn)17緒論一、列管式換熱器的結(jié)構(gòu)和特點(diǎn)管殼式換熱器(shell and tube heat exchanger)又稱列管式換熱器。是以封閉在殼體中管束的壁面作為傳熱面的間壁式換熱器。這種換熱器結(jié)構(gòu)較

14、簡單，操作可靠，可用各種結(jié)構(gòu)材料（主要是金屬材料）制造，能在高溫、高壓下使用，是目前應(yīng)用最廣的類型。 根據(jù)冷熱流體換熱方式的不同可將換熱器分為混合式換熱器、蓄熱式換熱器和間壁式換熱器。其中以間壁式換熱器應(yīng)用最為廣泛，型式也最為多樣。按換熱器傳熱面形狀和結(jié)構(gòu)的特點(diǎn)，間壁式換熱器又可分為管式換熱器、板式換熱器和特殊式換熱器三類。列管式換熱器是化工生產(chǎn)中常用的一種換熱設(shè)備, 結(jié)構(gòu)簡單, 適應(yīng)性強(qiáng); 單位體積所具有的傳熱面積大并傳熱效果好; 而且種類多, 型號(hào)全。列管換熱器主要特點(diǎn)： 1、耐腐蝕性：聚丙烯具有優(yōu)良的耐化學(xué)品性，對(duì)于無機(jī)化合物，不論酸，堿、鹽溶液，除強(qiáng)氧化性物料外，幾乎直到100都對(duì)其無

15、破壞作用，對(duì)幾乎所有溶劑在室溫下均不溶解，一般烷、徑、醇、酚、醛、酮類等介質(zhì)上均可使用。2、耐溫性：聚丙烯塑料熔點(diǎn)為164-174，因此一般使用溫度可達(dá)110-125。3、無毒性：不結(jié)垢，不污染介質(zhì)，也可用于食品工業(yè)。4、重量輕：對(duì)設(shè)備安裝維修極為方便。二、管殼式換熱器的選用和設(shè)計(jì)計(jì)算步驟1、浮頭式換熱器結(jié)構(gòu) 換熱器的一塊管板用法蘭與外殼相連接，另一塊管板不與外殼連接，以使管子受熱或冷卻時(shí)可以自由伸縮，但在這塊管板上連接一個(gè)頂蓋，稱之為“浮頭”，所以這種換熱器叫做浮頭式換熱器。其優(yōu)點(diǎn)是：管束可以拉出，以便清洗；管束的膨脹不變殼體約束，因而當(dāng)兩種換熱器介質(zhì)的溫差大時(shí)，不會(huì)因管束與殼體的熱膨脹量的

16、不同而產(chǎn)生溫差應(yīng)力。其缺點(diǎn)為結(jié)構(gòu)復(fù)雜，造價(jià)高。浮頭式換熱器，管束一端的管板可自由浮動(dòng)，完全消除了熱應(yīng)力;且整個(gè)管束可從殼體中抽出,便于機(jī)械清洗和檢修。浮頭式換熱器的應(yīng)用較廣，但結(jié)構(gòu)比較復(fù)雜，造價(jià)較高。 浮頭式換熱器2、試算初步選設(shè)備規(guī)格確定流體在換熱器中的流動(dòng)途徑。附表一附表一 列管式換熱器易燃、易爆液體和氣體允許的安全流速液體名稱乙醚、二氧化碳、苯甲醇、乙醇、汽油丙酮?dú)錃獍踩魉?，m/s123108根據(jù)傳熱任務(wù)計(jì)算熱負(fù)荷q。確定流體在換熱器兩端的溫度，選擇管殼式換熱器的類型；計(jì)算定性溫度，并確定在定性溫度下的物體物性。計(jì)算平均溫度差，并根據(jù)溫度校正系數(shù)不小于0.8的原則，決定殼程數(shù)。依據(jù)總傳

17、熱系數(shù)的經(jīng)驗(yàn)值范圍，選定總傳熱系數(shù)k。由初步算出s，并確定換熱器基本尺寸。 換熱管規(guī)格和排列選擇換熱管直徑越小，換熱器單位容積的傳熱面積越大。因此對(duì)于潔凈的流體可完管徑可取得小些。但對(duì)于不潔凈或易結(jié)垢的流體，管徑應(yīng)取的大些，以免堵塞。為了制造和維修的方便，我國目前試行的系列標(biāo)準(zhǔn)規(guī)定采用f192mm和f252.5mm兩種規(guī)格，管長有1.5、2.0、3.0、6.0m，排列方式：正三角形、正方形直列和錯(cuò)列排列，見下圖。各種排列方式的優(yōu)點(diǎn)：3、計(jì)算管程，殼程壓強(qiáng)降 初步計(jì)算管程，殼程流體的流速和壓強(qiáng)降，檢查結(jié)果是否合理，滿足工藝要求。若壓強(qiáng)降不符合要求，再確定管程數(shù)或折流板間距，或重新調(diào)整流速，再確定

18、各種尺寸，直到壓降滿足要求為止。4、核算中傳熱系數(shù)根據(jù)流體性質(zhì)選擇適當(dāng)?shù)墓笇訜嶙鑢，由r、和計(jì)算，再由傳熱基本方程計(jì)算。當(dāng)小于初選換熱器實(shí)際所具有的傳熱面積，則計(jì)算可行。考慮到所用換熱器計(jì)算式的準(zhǔn)確度及其他未可預(yù)料的因素，應(yīng)使選用換熱器面積有15%25%的裕度，即=1.151.25，否則應(yīng)重新估計(jì)一個(gè)，重復(fù)以上計(jì)算。 符號(hào)說明office.children are in need of early detection, early intervention. early rehabilitation concept is relatively weak, is generally believ

19、ed that developing children behind with the growth of the age will continue to improve, to increase the propaganda of rehabilitation policy and the concept of rehabilitation is crucial. for this center to increase efforts to promote the relentless efforts: is to assist the city fimitic in national e

20、ar care day national helping the disabled day during major festivals held special rehabilitation knowledge lectures, rehabilitation policy and rehabilitation concept and a series of publicity activities; the second is on a monthly basis to carry out parent training and rehabilitation guidance into t

21、he family and other rehabilitation services. two regulations promulgated in party power for a long time and under the condition of governing the country according to law, implement the full strictness of strategic deployment, implementation by board trustee administering the party and strengthen the

22、 inner-party supervision of major initiatives. two rules match, the guidelines adhere to the positive advocacy, lide, party members and cadres to visible, reach the high standards; around discipline cracked the requirements of the regulations, set out a negative list, and focus on state control, whi

23、ch gives the party organizations and party members out of the bottom line. the following, mainly from four to two party rule interpretation: first part of both necessity and process of legislative changes within the party; part two interpretation of legislative changes within the party principles of

24、 part two of regulation within the party after the third major change and several key issues need part on how well the two implementation of inner-party regulations. a, the guidelines and the regulations of the need for revision and revision process of central committee of cpc party members and lead

25、ing cadres honesty in politics a number of amendments to the guidelines and the chinese communist party disciplinary regulations classified as 2015 1 the focus of strengthening the construction of partys laws and regulations. two party rule revisions last year, centralized the party wisdom, gather c

26、onsensus, learn from historical experience, respect for wisdom, reflecting the unity of inheritance and innovation; follow the correct direction and seize the limited objectives, uphold the partys leadership, people, centered on solving problems. new standards and regulations, as amended, and reflec

27、ts the partys 18 and 18 in the third, four in the plenary session, reflects the experience of studying and implementing the xi series of important speech, general secretary, reflects the partys 18 since the comprehensive practice of strictly administering the party. (a) the need to amend the two reg

28、ulations in the party of the code was in 1997 the cpc party members and leading cadres honesty in politics a number of standards (for trial implementation) revised on the basis of which, published in january 2010, on strengthening the construction of leading cadres play an important role. but with t

29、he deepening of the party controls the party, strictly administering the party, has been unable to fully adapt to the needs. a is content had fan, 8 a ban, and 52 a no to remember, and also to practice line; ii is gel refining positive advocate insufficient, ban sex terms too much, no reflected self

30、-discipline of17英文字母b折流板間距，m;c系數(shù)，無量綱；d管徑，m；d換熱器外殼內(nèi)徑，m；f摩擦系數(shù)；f系數(shù)；h圓缺高度；k總傳熱系數(shù)，w/（m2）；l管長，m；m程數(shù)；n指數(shù)； 管數(shù)； 程數(shù)；n管數(shù)； 程數(shù)；nb折流板數(shù)；nu努賽爾準(zhǔn)數(shù)；p壓力，pa； 因數(shù)；pr普蘭特準(zhǔn)數(shù)；q熱通量，w/m2；q傳熱速率，w；r半徑，m； 氣化熱，kj/kgr熱阻，m2/w 因數(shù)；re雷諾準(zhǔn)數(shù)；s傳熱面積，m2；t冷流體溫度，； 管心距，m；t熱流體溫度，；u流速，m/s；w質(zhì)量流量，kg/s。希臘字母對(duì)流傳熱系數(shù)，w/(m)有限差值；導(dǎo)熱系數(shù)，w/(m)；粘度，pas；密度，kg/m3；

31、校正系數(shù)。下標(biāo)i管內(nèi)；m平均；o管外；s污垢。工藝計(jì)算一、確定物性數(shù)據(jù)定性溫度：可取流體進(jìn)出口溫度的平均值殼程水蒸汽溫度的定性溫度為（300kpa絕壓下的水蒸汽t=133.3）管程流體的定性溫度為=根據(jù)定性溫度，分別查取有關(guān)物性數(shù)據(jù)水蒸汽在133.3下的有關(guān)物性數(shù)據(jù)如下密度 =1.651 kg/m3定壓比熱容 =1.9735 kj/(kg)導(dǎo)熱系數(shù) =0.0265971 w/(m)黏度 =1.33105 pas液化熱 =2168.1kj/kg苯-甲苯混合液（x1=0.4）在57下的物性數(shù)據(jù)如下密度 =834.5295716 kg/m3定壓比熱容 =1.686 kj/(kg)導(dǎo)熱系數(shù) =0.12

32、3438163 w/(m)黏度 =3.93104 pas二、確定計(jì)劃方案選擇換熱器類型 兩流體溫度變化情況：熱流體（水蒸汽）進(jìn)口溫度133.3，出口溫度133.3；冷流體（苯-甲苯）進(jìn)口溫度20，出口溫度94。估計(jì)管壁溫和殼壁溫之差較大，再加上所受壓力較大，因此選用浮頭式換熱器。流動(dòng)空間及流速的確定由于飽和蒸汽宜走殼程，飽和蒸汽比較清潔，而且冷凝液容易排出；苯-甲苯混合液走管程。三、估計(jì)總傳熱面積熱流量水蒸汽流量平均傳熱溫度傳熱面積，根據(jù)流體情況，假設(shè)四、工藝結(jié)構(gòu)尺寸由浮頭式（內(nèi)導(dǎo)流）換熱器的基本參數(shù)表*查得殼徑/mm700管子尺寸/mmf252.5mm公稱壓強(qiáng)/mpa2.5管長/m4.5公稱

33、面積92.1管子總數(shù)268管程數(shù)2管子排列方法正方形斜轉(zhuǎn)45若選用該型號(hào)換熱器，則要求過程的總傳熱系數(shù)為五、換熱器核算1、核算壓強(qiáng)降管程流動(dòng)阻力管程阻力等于流體流經(jīng)傳熱管直管阻力和管程局部阻力之和。即 為管程結(jié)垢校正系數(shù)，量綱為1，對(duì)f252.5mm的管子可近似取1.4。*化工原理上冊(cè)，2）浮頭式（內(nèi)導(dǎo)流）換熱器的基本參數(shù)，天津大學(xué)出版社2005年版，第367頁。管程流體通截面積管程流體流速設(shè)管壁粗糙度，查圖*得所以 管程流動(dòng)阻力小于70kpa，符合設(shè)計(jì)條件。 2、熱流量核算殼程對(duì)流傳熱系數(shù)蒸汽在水平管束外冷凝，可采用凱恩（kern）估算式，根據(jù)兩流體溫度與傳熱系數(shù)，假設(shè)tw=115管程對(duì)流傳

34、熱系數(shù)*化工原理上冊(cè)，圖1-27 摩擦系數(shù)與雷諾準(zhǔn)數(shù)及相對(duì)粗糙度的關(guān)系，天津大學(xué)出版社2005年版，第54頁。普蘭特準(zhǔn)數(shù)傳熱系數(shù)k查表*知污垢熱阻，管壁導(dǎo)熱系數(shù) 故此換熱器合適。*化工原理上冊(cè)，壁面污垢的熱阻125370087（污垢系數(shù)），天津大學(xué)出版社2005年版，第354頁。傳熱面積裕度傳熱面積該換熱器的實(shí)際傳熱面積a 則該換熱器的面積裕度按式/在1.151.25范圍內(nèi)，傳熱面積裕度合適，該換熱器能完成生產(chǎn)任務(wù)。故該換熱器合適。3、壁溫核算因管壁很薄，且管壁熱阻很小，故壁溫可按式 計(jì)算。由于傳熱管內(nèi)側(cè)污垢熱阻較大，會(huì)使傳熱管壁溫升高，降低了殼體和傳熱管壁溫之差。但在操作初期，污垢熱阻較小，殼體和傳熱管間壁溫差可能較小。計(jì)算中應(yīng)按最不利的操作條件考慮，因此取兩側(cè)污垢熱阻為零計(jì)熱。于是上式變?yōu)?氣體平均溫度液體平均溫度（端流）帶入計(jì)算得 與凱恩式中假設(shè)相差不大，故假設(shè)合適。設(shè)計(jì)數(shù)據(jù)結(jié)果一覽表參數(shù)管程殼程流量（kg/h）90000進(jìn)/出口溫度（）20/94133.3/133.3壓力（kpa）常壓300（絕壓）物性參數(shù)定性溫度（）57密度（kg/m3）834.53935.3302定壓比熱容（j/(kg)）1686.13541973.5粘