.PAGE.2009級化學工程與工藝專業《化工原理》課程設計說明書題目：2.0×104噸/年正戊烷冷凝器的設計__班級__指導同組學生__完成時間：2012《化工原理》課程設計評分細則評審單元評審要素評審內涵評審等級檢查方法指導老師評分檢閱老師評分設計說明書35%格式規范是否符合規定的格式要求5-44-33-22-1格式標準內容完整設計任務書、評分標準、主要設備計算、作圖、后記、參考文獻、小組成員及承擔任務10-88-66-44-1設計任務書設計方案方案是否合理及是否有創新10-88-66-44-1計算記錄工藝計算過程計算過程是否正確、完整和規范10-88-66-44-1計算記錄設計圖紙30%圖面布置圖紙幅面、比例、標題欄、明細欄是否規范10-88-66-44-1圖面布置標準標注文字、符號、代號標注是否清晰、正確10-88-66-44-1標注標準與設計吻合圖紙設備規格與計算結果是否吻合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現場考察衛生與紀律設計室是否整潔、衛生、文明10-88-66-44-1答辯成績15%內容表述答辯表述是否清楚5-44-33-22-1現場考察內容是否全面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老師評閱老師〔簽名〔簽名年月日年月日目錄設計任務書····································································································41-1設計題目··········································································································41-2設計任務及操作條件·······················································································41-3設計說明書的內容··························································································41-4設計圖要求·······································································································4主要設備設計計算和說明············································································52-1確定流體流動空間···························································································52-2確定流體的物理性質·······················································································52-3計算熱負荷·····································································································52-4計算有效平均溫度差·······················································································52-5選取經驗傳熱系數K值···················································································62-6估算換熱面積·································································································62-7工藝結構尺寸·································································································62-8初選換熱器規·································································································72-9計算管程對流傳熱系數···············································································82-10計算壓降·······································································································93．工藝設計計算結果匯總表···········································································114．參考文獻·······································································································12后記·····················································································································13一、設計任務書1.設計題目：正戊烷冷凝器的設計。設計課題工程背景：煉油廠精餾塔塔頂冷凝器蒸汽主要是正戊烷,以此為原料設計一正戊烷冷凝器。

2.設計任務及操作條件〔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,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小時連續運行

〔6設備型式立式列管冷凝器

〔7設計項目

①設計方案簡介：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.設計說明書的內容

〔1課程名稱、首頁、目錄及頁碼；

〔2簡述設計內容,自己設計的特點,引用的標準等；

〔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結構及附件設計計算；〔8冷凝器的主要數據一覽表；

〔9設計結果評價；〔10附立式列管冷凝器總裝圖。

4.設計圖要求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、主要設備設計計算和說明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。正戊烷液體在定性溫度〔51.7℃下的物性數據：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據見下表流體溫度/℃密度/<kg/>黏度比熱容熱導正戊烷51.75960.182.340.13井水21.59980.98384.1820.6013.計算熱負荷kW4.計算有效平均溫度差逆流溫差℃5.選取經驗傳熱系數K值根據管程走井水,殼程走正戊烷,總傳熱系數,現暫取K=500。6.估算換熱面積7.工藝結構尺寸=1\*GB3①管徑和管內流速管徑為φ25mm2.5mm,管內流速為ui=1.0m/s。=2\*GB3②管程數和傳熱管數根據傳熱管內徑和流速確定單程傳熱管數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為=4/2=2<管程>傳熱管的總根數=642=128〔根=3\*GB3③殼體內徑采用兩管程結構,取管板利用率=0.7,則殼體內徑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,殼程入口應設置防沖擋板。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蒸汽流速為10m/s,則接管內徑mm出口接管取結管內的液體流速為1.5m/s,則接管內徑b管程水進出口接管取接管內水流速為1m/s,則接管內徑d=160mm8.初選換熱器規立式固定板式換熱器的規格如下：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：2管子排列方式：正三角形管數：128換熱器的實際換熱面積9.計算管程對流傳熱系數=1\*GB3①計算管程對流傳熱系數m3/s=2\*GB3②計算殼程對流傳熱系數現假設管外壁溫=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℃下的數據,在層流下：=3\*GB3③確定污垢熱阻=4\*GB3④總傳熱系數碳素鋼：=45所選用換熱器的安全系數為：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基本一致,可以接受。核算流型,冷凝負荷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、工藝設計計算結果匯總表換熱器主要工藝結構參數和計算結果一覽表參數管程殼程流率kg/h718922525.25溫度〔進/出>/℃20/2351.7/51.7物性參數定性溫度/℃21.551.7密度/<kg/m3>998596比熱容/〔kJ/kg/℃〕4.1822.34黏度/mPa·s0.98380.18熱導率/〔W/<m·℃>〕0.6010.13普朗特數6.85設備結構參數型式固定管板式臺數1殼體內徑/mm450殼程數1管子規格φ25mm×2.5mm管心距/mm32管長/mm2000管子排列正三角形管子數目/根128折流板數/塊12傳熱面積/m219.0912折流板距/mm153管程數2材質碳鋼主要計算結果管程殼程流速/<m/s>10.078傳熱膜系數/〔W/<m2·℃>〕4165.4869.3污垢熱阻/<m2·℃/W>0.0001720.000172熱負荷/Kw250.54傳熱溫差/℃30.2傳熱系數/〔W/<m2·℃>〕526.3裕度/%21.1四、參考文獻上海醫藥設計院.化工工藝設計手冊<上、下>.北京：化學工業出版社,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.石油化工基礎數據手冊,北京：化學工業出版社,1982付家新,王為國,肖穩發主編.化工原理課程設計,北京：化學工業出版社,2010時鈞,汪家鼎等.化學工程手冊,.北京：化學工業出版社,1986后記通過此次課程設計,使我更加扎實的掌握了有關設計冷凝換熱器方面的知識,在設計過程中雖然遇到了一些問題,但經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。在課程設計過程中,我們不斷發現錯誤,不斷改正,不斷領悟,不斷獲取。最終的檢測調試環節,本身就是在踐行"過而能改,善莫大焉"的知行觀。這次課程設計終于順利完成了,在設計中遇到了很多問題,最后在老師的指導下,終于迎刃而解。在今后社會的發展和學習實踐過程中,一定要不懈努力,不