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3 畢業(yè)設(shè)計誠信聲明 本人鄭重聲明:所呈交的畢業(yè)設(shè)計,是本人在指導(dǎo)老師的指導(dǎo)下,獨立進行研究工作所取得的成果,成果不存在知識產(chǎn)權(quán)爭議,除文中已經(jīng)注明引用的內(nèi)容外,本設(shè)計不含任何其他個人或集體已經(jīng)發(fā)表或撰寫過的作品成果。對本文的研究做出重要貢獻的個人和集體均已在文中以明確方式標(biāo)明。本人完全意識到本聲明的法律結(jié)果由本人承擔(dān)。 作者簽名: xxx 2021 年 12 月 6 日 4 目 錄 一、設(shè)計任務(wù)書 ????????????????????????? 1 二、摘要 ?????????????????? ?????????? 3 三、緒論 ???????????????????????????? 7 ?????????????????????? 7 ???????????????????? 7 苯乙酮法 ?????????????????????????? 7 乙苯和丙烯共氧化 ????????????????????? 7 乙苯催化脫氫法 ?????????????????????? 8 、副化學(xué)反應(yīng)式 ???? ??????????????????? 8 、化學(xué)組成及化學(xué)性質(zhì) ??????????????????? 8 ?????????????????????????? 10 脫氫反應(yīng)總述 ??????????????????????? 10 苯乙烯蒸餾總述 ?????????????????????? 11 四、物料及熱量衡算 ??????????????????????? 15 (一)、苯乙烯生產(chǎn)全系統(tǒng)的物料衡算 ??????????????? 15 算 ??????????????????????? 15 反應(yīng)系統(tǒng)進料量計算 ???????????????????? 15 出水冷冷凝器的氣液組成 ?????????????????? 18 出鹽水冷凝器的氣液組成 ?????????????????? 20 油水分離器水油組成 ???????????????????? 21 ?????????????????????? 23 苯乙烯精餾塔的物料衡算 ?????????????????? 24 苯、甲苯蒸出塔的物料衡算 ????????????????? 26 苯乙烯初餾塔物料衡算 ??????????????????? 28 乙苯蒸出塔的物料衡算 ??????????????????? 30 (二)、脫氫系統(tǒng)的熱量衡算 ??????????????????? 32 1.蒸發(fā)器 ?????????????????????????? 32 第一預(yù)熱器 ???????????????????????? 33 熱交換器 ??????????????????????? ?? 34 第二預(yù)熱器 ???????????????????????? 34 反應(yīng)器 ?????????????????????????? 35 四、感謝信 ?????????????????????????? 40 五、參考文獻 ????????????????????????? 41 5 摘要 苯乙烯 (SM)是生產(chǎn)塑料和合成橡膠的重要基本有機原料,主要用于生產(chǎn)聚苯乙烯,也可用于制備丁苯橡膠、苯乙烯一順丁烯 苯乙烯嵌段共聚物、不飽和聚酯等。乙苯催化脫氫法是目前國內(nèi)外生產(chǎn)苯乙烯的主要方法,采用的 催化劑主要是 FeK系催化劑,其中 Fe2O3。是活性組分、 K2O 是活性促進劑, K2O 的引入使鐵系催化劑的活性有了顯著提高,可以在較低的水比下應(yīng)用,但 K2O 含量過高存在著鉀的流失問題。 .為了解決催化劑在使用過程中存在的問題,作者采用固定床反應(yīng)器,以自制的高鐵低鉀氧化鐵為催化劑,考察反應(yīng)溫度、進料比和催化劑活性對乙苯轉(zhuǎn)化率、苯乙烯選擇性和苯乙烯收率的影響,確定了最佳的工藝條件。 本設(shè)計為 10萬噸 /年乙苯脫氫制苯乙烯工藝流程,工藝采用具有低活性、高選擇性的氧化鐵系催化劑,參照魯姆斯 (Lummus)公司生產(chǎn)苯乙烯的技 術(shù),以乙苯脫氫法生產(chǎn)苯乙烯。 設(shè)計內(nèi)容主要包括:工藝流程設(shè)計、工藝計算、設(shè)備設(shè)計等。 本設(shè)計主要由脫氫反應(yīng)和精餾兩個工序系統(tǒng)所組成。乙苯脫氫反應(yīng)在絕熱固定床反應(yīng)器中進行,反應(yīng)物送至精餾工序。先經(jīng)乙苯 — 苯乙烯塔分離出乙苯(含苯、甲苯)和粗苯乙烯(帶重組分及焦油)。乙苯餾分送苯 甲苯塔分成苯、甲苯餾分和回收乙苯,回收乙苯返回脫氫工序。粗苯乙烯送精餾塔分成精苯乙烯和焦油。 工藝計算包括主反應(yīng)器和精餾塔的物料衡算以及熱量衡算。 設(shè)備設(shè)計主要是對乙苯 /苯乙烯分離塔進行設(shè)計,計算出實際塔板數(shù) 26 塊,進料在第 13塊 板,塔徑 ,塔高 20m。 齊魯 200kt/2 苯乙烯裝置改造完成后,乙苯 /苯乙烯分離塔操作指標(biāo)一直達不到設(shè)計要求,塔頂苯乙烯含量高達 8%左右,遠高于設(shè)計值 1%的要求,而塔釜乙苯含量在 %左右,也高于 %的設(shè)計值,而且進料負荷也沒有達到設(shè)計的生產(chǎn)能力,進料負荷越高,奮力效果越差。 通過制定工藝操作方案,搜索和考察了各種不同工藝條件對操作狀況的影響,并通過冷模實驗,模擬軟件計算,通過操作數(shù)據(jù)的對比和分析,找出了該塔存在的問題,分析了問題產(chǎn)生的原因。在此基礎(chǔ)上,提出了乙苯 /苯乙烯分離塔 6 的改造方案 。 對分離塔成功的進行了技術(shù)改造,更換了乙苯 /苯乙烯分離塔精餾段部分填料和部分塔內(nèi)件,解決了困擾該塔正常運行的主要矛盾,使得改造后的分離塔運行效果明顯好轉(zhuǎn)。塔頂苯乙烯質(zhì)量分?jǐn)?shù)由原來的 8%降至 3%。 在進一步模擬分析研究的基礎(chǔ)上,對該塔進行了一系列的優(yōu)化操作,通過調(diào)整精餾塔的操作壓力與回流比等工藝系數(shù),使得該塔的分離效果達最終達到甚至超過設(shè)計指標(biāo),裝置的生產(chǎn)能力得到大幅度的提高。塔頂苯乙烯含量小于 1%,塔釜乙苯含量小于 %,苯乙烯產(chǎn)品純度達到 %以上,取得了較好的經(jīng)濟效益。 關(guān)鍵詞 :乙苯; 苯乙烯;精餾塔;參數(shù)優(yōu)化 ;脫氫;蒸餾 7 Abstract Styrene (SM) is the production of plastics and synthetic rubber in important basic anic raw materials, mainly for the production of polystyrene, can also be used for the preparation of a styrenebutadiene rubber, maleatestyrene block copolymers, unsaturated polyester, etc. Ethylbenzene catalytic dehydrogenation method is by far the major domestic and foreign production of styrene, used catalyst methodology mainly FeK catalysts, Fe2O3. Is the active ponent, K2O is active promoters, K2O introduction to ironbased catalyst39。s activity has been significantly improved, can lower water ratios apply, K2O content too high potassium loss exists.. in order to solve the catalyst in the use process problems, the author takes a fixed bed reactor to selfmade iron and low potassium oxide as a catalyst, visit reaction temperature, feed ratio and catalyst activity on Ethylbenzene conversion rate, the selectivity of polystyrene and styrene yield, determine the best process conditions. This design is 10 million tons/year of ethyl benzene dehydrogenation processes, process with low activity, high selectivity of iron oxide catalysts, reference rhuems (Lummus) pany production of styrene technology, to production of styrene Ethylbenzene dehydrogenation. Designs include: process design, process calculation, equipment design, etc. This design is mainly posed of dehydrogenation and distillation two operation systems. Ethylbenzene dehydrogenation in adiabatic fixed bed reactor, reactants to the distillation process. First Ethylbenzenestyrene Tower isolation of Ethylbenzene (benzene, toluene) and styrene (with reanization and tar). Ethyl benzene fractions to benzenetoluene Tower intobenzene, toluene, Ethylbenzene distillate and recycle recycling Ethylbenzene returns dehydrogenation processes. Crude distillation into fine styrene sent to styrene and tar. Process calculation includes the main reactor and distillation column material balance and thermal balance. Equipment design mainly on Ethylbenzene/styrene separation column for design, calculation of the actual number of trays, feeding in 26 block 13 block plate, diameter , Tower high 20m. Qilu 200kt/2 styrene plant pleted, Ethylbenzene/styrene separation column operation indicators a direct access to the design requirements, the Tower of styrene content up to 8%, much higher than the design value of 1%, while the Tower Kettle Ethylbenzene content in %, higher than the design value of % and feed load does not meet the design production capacity, higher feed load, to lower the effect. Programme through the development of technology operations, search and inspect a variety of different conditions on the operation status, and through cold model experiments, modeling