第5組(正戊烷冷凝器的設(shè)計)

.PAGE.2009級化學(xué)工程與工藝專業(yè)《化工原理》課程設(shè)計說明書題目：2.0×104噸/年正戊烷冷凝器的設(shè)計__班級__指導(dǎo)同組學(xué)生__完成時間：2012《化工原理》課程設(shè)計評分細(xì)則評審單元評審要素評審內(nèi)涵評審等級檢查方法指導(dǎo)老師評分檢閱老師評分設(shè)計說明書35%格式規(guī)范是否符合規(guī)定的格式要求5-44-33-22-1格式標(biāo)準(zhǔn)內(nèi)容完整設(shè)計任務(wù)書、評分標(biāo)準(zhǔn)、主要設(shè)備計算、作圖、后記、參考文獻、小組成員及承擔(dān)任務(wù)10-88-66-44-1設(shè)計任務(wù)書設(shè)計方案方案是否合理及是否有創(chuàng)新10-88-66-44-1計算記錄工藝計算過程計算過程是否正確、完整和規(guī)范10-88-66-44-1計算記錄設(shè)計圖紙30%圖面布置圖紙幅面、比例、標(biāo)題欄、明細(xì)欄是否規(guī)范10-88-66-44-1圖面布置標(biāo)準(zhǔn)標(biāo)注文字、符號、代號標(biāo)注是否清晰、正確10-88-66-44-1標(biāo)注標(biāo)準(zhǔn)與設(shè)計吻合圖紙設(shè)備規(guī)格與計算結(jié)果是否吻合10-88-66-44-1比較圖紙與說明書平時成績20%出勤計算、上機、手工制圖10-88-66-44-1現(xiàn)場考察衛(wèi)生與紀(jì)律設(shè)計室是否整潔、衛(wèi)生、文明10-88-66-44-1答辯成績15%內(nèi)容表述答辯表述是否清楚5-44-33-22-1現(xiàn)場考察內(nèi)容是否全面5-44-33-22-1回答問題回答問題是否正確5-44-33-22-1總分綜合成績成績等級指導(dǎo)老師評閱老師〔簽名〔簽名年月日年月日目錄設(shè)計任務(wù)書····································································································41-1設(shè)計題目··········································································································41-2設(shè)計任務(wù)及操作條件·······················································································41-3設(shè)計說明書的內(nèi)容··························································································41-4設(shè)計圖要求·······································································································4主要設(shè)備設(shè)計計算和說明············································································52-1確定流體流動空間···························································································52-2確定流體的物理性質(zhì)·······················································································52-3計算熱負(fù)荷·····································································································52-4計算有效平均溫度差·······················································································52-5選取經(jīng)驗傳熱系數(shù)K值···················································································62-6估算換熱面積·································································································62-7工藝結(jié)構(gòu)尺寸·································································································62-8初選換熱器規(guī)·································································································72-9計算管程對流傳熱系數(shù)···············································································82-10計算壓降·······································································································93．工藝設(shè)計計算結(jié)果匯總表···········································································114．參考文獻·······································································································12后記·····················································································································13一、設(shè)計任務(wù)書1.設(shè)計題目：正戊烷冷凝器的設(shè)計。設(shè)計課題工程背景：煉油廠精餾塔塔頂冷凝器蒸汽主要是正戊烷,以此為原料設(shè)計一正戊烷冷凝器。

2.設(shè)計任務(wù)及操作條件〔1處理量：2.0×104噸/年

〔2正戊烷冷凝溫度為51.7℃,冷凝液于飽和液體下離開冷凝器；

〔3冷卻介質(zhì),地下水,入口溫度：20℃；

〔4允許壓強降：不大于105Pa

〔5每年按330天計,每天24小時連續(xù)運行

〔6設(shè)備型式立式列管冷凝器

〔7設(shè)計項目

①設(shè)計方案簡介：對確定的工藝流程及換熱器型式進行簡要論述；

②換熱器的工藝計算：確定換熱器的傳熱面積；

③選擇合適的立式列管冷凝器并進行較核計算；

④繪制換熱器總裝配圖。

3.設(shè)計說明書的內(nèi)容

〔1課程名稱、首頁、目錄及頁碼；

〔2簡述設(shè)計內(nèi)容,自己設(shè)計的特點,引用的標(biāo)準(zhǔn)等；

〔3熱量衡算及初步估算換熱面積；〔4冷凝器的選型及流動空間的選擇；〔5工藝流程圖；〔6冷凝器的校核計算；

〔7結(jié)構(gòu)及附件設(shè)計計算；〔8冷凝器的主要數(shù)據(jù)一覽表；

〔9設(shè)計結(jié)果評價；〔10附立式列管冷凝器總裝圖。

4.設(shè)計圖要求A2圖紙繪制冷凝器裝配圖一張、兩個局部放大圖。CAD圖自由選做1-2個部件。二、主要設(shè)備設(shè)計計算和說明1.確定流體流動空間冷水走管程,正戊烷走殼程,有利于正戊烷的散熱和冷凝。2.計算流體的定性溫度,確定流體的物理性質(zhì)。正戊烷液體在定性溫度〔51.7℃下的物性數(shù)據(jù)：ρ=596kg/,,,,。井水的定性溫度：入口溫度=20℃,出口溫度為23℃井水的定性溫度為℃兩流體的溫差,故選固定管式換熱器。兩流體在定性溫度下的物性數(shù)據(jù)見下表流體溫度/℃密度/<kg/>黏度比熱容熱導(dǎo)正戊烷51.75960.182.340.13井水21.59980.98384.1820.6013.計算熱負(fù)荷kW4.計算有效平均溫度差逆流溫差℃5.選取經(jīng)驗傳熱系數(shù)K值根據(jù)管程走井水,殼程走正戊烷,總傳熱系數(shù),現(xiàn)暫取K=500。6.估算換熱面積7.工藝結(jié)構(gòu)尺寸=1\*GB3①管徑和管內(nèi)流速管徑為φ25mm2.5mm,管內(nèi)流速為ui=1.0m/s。=2\*GB3②管程數(shù)和傳熱管數(shù)根據(jù)傳熱管內(nèi)徑和流速確定單程傳熱管數(shù)ns==64〔根按單程管計算所需換熱管的長度LL=m取傳熱管長l=2m,則該換熱器的管程數(shù)為=4/2=2<管程>傳熱管的總根數(shù)=642=128〔根=3\*GB3③殼體內(nèi)徑采用兩管程結(jié)構(gòu),取管板利用率=0.7,則殼體內(nèi)徑D=1.05t450mm=4\*GB3④折流板采用弓形折流板,取弓形折流板圓缺高度為殼體內(nèi)徑的25%,則切去的圓缺高度為h=0.25450=112.5,取h=113mm。取折流板間距為B=0.34D=0.34450=153mm。則折流板數(shù)NB=—1=—112〔塊折流板圓缺水平面安裝=5\*GB3⑤拉桿直徑為φ12mm,殼程入口應(yīng)設(shè)置防沖擋板。⑥殼程流通截面積和殼程流體流速殼程流通截面積=7\*GB3⑦接管a殼程接管進口接管取接管內(nèi)蒸汽流速為10m/s,則接管內(nèi)徑mm出口接管取結(jié)管內(nèi)的液體流速為1.5m/s,則接管內(nèi)徑b管程水進出口接管取接管內(nèi)水流速為1m/s,則接管內(nèi)徑d=160mm8.初選換熱器規(guī)立式固定板式換熱器的規(guī)格如下：公稱直徑D：450mm管長L：2.0m公稱換熱面積A：20管子直徑：φ25mm2.5mm管程數(shù)：2管子排列方式：正三角形管數(shù)：128換熱器的實際換熱面積9.計算管程對流傳熱系數(shù)=1\*GB3①計算管程對流傳熱系數(shù)m3/s=2\*GB3②計算殼程對流傳熱系數(shù)現(xiàn)假設(shè)管外壁溫=30℃,則冷凝液膜的平均溫度為℃,在此溫度下的物性沿用飽和溫度51.7℃下的數(shù)據(jù),在層流下：=3\*GB3③確定污垢熱阻=4\*GB3④總傳熱系數(shù)碳素鋼：=45所選用換熱器的安全系數(shù)為：表明該換熱器的傳熱面積裕度符合要求。=5\*GB3⑤核算壁溫與冷凝液流型核算壁溫時,一般忽略管壁熱阻,按以下近似計算公式計算這與假設(shè)基本一致,可以接受。核算流型,冷凝負(fù)荷10.計算壓降=1\*GB3①計算管程壓降=2\*GB3②計算殼程壓力降殼程為恒溫恒壓蒸汽冷凝,其壓降可忽略。由此可知,所選換熱器合適。三、工藝設(shè)計計算結(jié)果匯總表換熱器主要工藝結(jié)構(gòu)參數(shù)和計算結(jié)果一覽表參數(shù)管程殼程流率kg/h718922525.25溫度〔進/出>/℃20/2351.7/51.7物性參數(shù)定性溫度/℃21.551.7密度/<kg/m3>998596比熱容/〔kJ/kg/℃〕4.1822.34黏度/mPa·s0.98380.18熱導(dǎo)率/〔W/<m·℃>〕0.6010.13普朗特數(shù)6.85設(shè)備結(jié)構(gòu)參數(shù)型式固定管板式臺數(shù)1殼體內(nèi)徑/mm450殼程數(shù)1管子規(guī)格φ25mm×2.5mm管心距/mm32管長/mm2000管子排列正三角形管子數(shù)目/根128折流板數(shù)/塊12傳熱面積/m219.0912折流板距/mm153管程數(shù)2材質(zhì)碳鋼主要計算結(jié)果管程殼程流速/<m/s>10.078傳熱膜系數(shù)/〔W/<m2·℃>〕4165.4869.3污垢熱阻/<m2·℃/W>0.0001720.000172熱負(fù)荷/Kw250.54傳熱溫差/℃30.2傳熱系數(shù)/〔W/<m2·℃>〕526.3裕度/%21.1四、參考文獻上海醫(yī)藥設(shè)計院.化工工藝設(shè)計手冊<上、下>.北京：化學(xué)工業(yè)出版社,1986柴誠敬,張國亮等.化工原理.天津：高等教育出版社,2010盧煥章等.石油化工基礎(chǔ)數(shù)據(jù)手冊,北京：化學(xué)工業(yè)出版社,1982付家新,王為國,肖穩(wěn)發(fā)主編.化工原理課程設(shè)計,北京：化學(xué)工業(yè)出版社,2010時鈞,汪家鼎等.化學(xué)工程手冊,.北京：化學(xué)工業(yè)出版社,1986后記通過此次課程設(shè)計,使我更加扎實的掌握了有關(guān)設(shè)計冷凝換熱器方面的知識,在設(shè)計過程中雖然遇到了一些問題,但經(jīng)過一次又一次的思考,一遍又一遍的檢查終于找出了原因所在,也暴露出了前期我在這方面的知識欠缺和經(jīng)驗不足。實踐出真知,通過親自動手制作,使我們掌握的知識不再是紙上談兵。過而能改,善莫大焉。在課程設(shè)計過程中,我們不斷發(fā)現(xiàn)錯誤,不斷改正,不斷領(lǐng)悟,不斷獲取。最終的檢測調(diào)試環(huán)節(jié),本身就是在踐行"過而能改,善莫大焉"的知行觀。這次課程設(shè)計終于順利完成了,在設(shè)計中遇到了很多問題,最后在老師的指導(dǎo)下,終于迎刃而解。在今后社會的發(fā)展和學(xué)習(xí)實踐過程中,一定要不懈努力,不