年產(chǎn)5萬噸乙醇化工廠設(shè)計【含4張CAD圖紙】

喜歡這套資料就充值下載吧。資源目錄里展示的都可在線預(yù)覽哦。下載后都有，請放心下載，文件全都包含在內(nèi)，有疑問咨詢QQ:1064457796

年產(chǎn)5萬噸乙醇化工廠設(shè)計 年產(chǎn)5萬噸乙醇化工廠設(shè)計 1 設(shè)計的目的、意義以及用途 本課題要是從工程角度對即將畢業(yè)的本科生進(jìn)行一次全面的綜合訓(xùn)練過程。主要完成工藝計算和工程圖設(shè)計，對化工生產(chǎn)過程和生產(chǎn)管理有一個比較全面的了解，達(dá)到社會對人才知識的基本要求。 乙醇是在常溫、常壓下是一種無色、透明、有香味、易揮發(fā)的液體，熔點-117.3℃，沸點78.5℃，凝固點為-114.1℃．密度0.7893g/cm3,能與水及大多數(shù)有機溶劑以任意比混溶。乙醇易燃,它的爆炸極限為3.5%～18%,閃點11℃,使用時須注意安全。 乙醇的用途按需求量多少可分為三方面：用量最大的燃料乙醇，科研用的乙醇化學(xué)試劑，化工醫(yī)藥用乙醇。 1. 乙醇是一種新能源，其優(yōu)勢在于發(fā)酵乙醇屬于可再生能源，乙醇不僅是一種優(yōu)良燃料，它作為一種優(yōu)良燃油品質(zhì)改善劑被廣泛使用，其優(yōu)良特性主要有：乙醇是燃油的增氧劑，是汽油燃燒完全，大大節(jié)能和環(huán)保的；乙醇具有很好的抗爆性能；乙醇是優(yōu)于太陽能的一種生物轉(zhuǎn)化能源，是可再生資源。 2. 乙醇在醫(yī)藥方面的用途很廣：可作為大專院校及科研院所等的實驗室以餐飲業(yè)在燃料；可作為細(xì)胞生物學(xué)實驗和研究使用的優(yōu)良的固定劑和脫水劑，可作為優(yōu)良的防凍降溫介質(zhì)?？勺鳛槿剂弦胰?，乙酸，乙醚。 3乙醇工業(yè)的副產(chǎn)品 大型乙醇企業(yè)除主要生產(chǎn)乙醇外，還有如下副產(chǎn)物：優(yōu)質(zhì)顆粒飼料DDGS（全價干酒精糟）優(yōu)質(zhì)食用級CO2. CO2是發(fā)酵乙醇相伴生產(chǎn)的數(shù)量最大的副產(chǎn)品。高純度食用級CO2除用做碳酸飲料外還有氣體保護(hù)焊接，藥物萃取，溫室生產(chǎn)等方面有較廣的用途；玉米油；玉米胚芽油是優(yōu)質(zhì)保健食品；玉米，小麥等為原料的大型究竟生產(chǎn)企業(yè)。還可以生產(chǎn)玉米淀粉，葡萄糖漿，果糖漿，玉米蛋白等，雜醇油是某些食用香料的主要原料。 2 選題的依據(jù)（理論依據(jù)、技術(shù)依據(jù)） 鑒于現(xiàn)代工業(yè)生產(chǎn)能力與實際需要之間的差距，擬設(shè)計年產(chǎn)5萬噸乙醇工廠，現(xiàn)代乙醇的工業(yè)化生產(chǎn)技術(shù)比較先進(jìn)，但是還有更多的新技術(shù)可以應(yīng)用到新的生產(chǎn)線上，對乙醇的純度及其應(yīng)用方面進(jìn)行了研究，以適應(yīng)我國市場方面的需求，適應(yīng)環(huán)保事業(yè)發(fā)展要求，推動社會經(jīng)濟(jì)發(fā)展。 3 方案選擇 3.1 原料的選擇是 我國農(nóng)副產(chǎn)品資源豐富，所以，主要采用微生物發(fā)酵法。微生物發(fā)酵法在采用不同發(fā)酵原料時生產(chǎn)乙醇的工藝有所不同，主要分為淀粉質(zhì)原料乙醇生產(chǎn)工藝，糖蜜原料乙醇生產(chǎn)工藝，工廠廢液及纖維素原料酒精生產(chǎn)工藝等。常用淀粉質(zhì)原料有薯類，谷物類，和某些含淀粉較多野生植物。 3.2 反應(yīng)方程式 本設(shè)計采用發(fā)酵法生產(chǎn)乙醇，發(fā)酵法是將葡萄糖在有能引起發(fā)酵的物質(zhì)存在的情況下，經(jīng)過蒸煮、糖化等各種不同的階段而轉(zhuǎn)化成乙醇，最后經(jīng)過蒸餾得到成品乙醇，其反應(yīng)過程如下： m(C6H12O5)＋1/2mH2O 糖化酶 1/2m（C12H22O11) 在發(fā)酵過程中，雙糖經(jīng)水解的到葡萄糖： C12H22O11+ H2O 麥芽糖酶 2C6H12O6 然后葡萄糖酒化： C6H12O 酒化酶 2CH3CH2OH+2CO2 3.3 工藝流程 （1）工藝流程示意圖 玉米 空氣 酵母子 粉碎車間 α-淀粉酶 空壓機 斜面培養(yǎng) 糊化車間 糖化酶 過濾器 三角瓶培養(yǎng) CO2 酒母罐 發(fā)酵車間 蒸餾車間 廢糟 乙醇 雜醇油 （2）工藝流程簡述 a原料經(jīng)皮帶輸送機運至地下貯箱，再經(jīng)斗士提升機將原料運輸至料斗，通過錘式粉碎機進(jìn)行粉碎，粉料經(jīng)絞龍輸送，同時加水1：3攪拌均勻，而后進(jìn)入粉漿罐，再進(jìn)入預(yù)煮罐，邊攪拌邊預(yù)熱，熱源為二次蒸汽，溫度為55℃，用往復(fù)泵送到蒸煮柱中，用蒸汽加熱到140—150℃，充滿后從頂部流出，以此進(jìn)入后熟器中，后熟時間 約90min,從后熟器出來物料進(jìn)入真空冷卻罐中，冷卻后的蒸煮醪（63℃）同糖化酶一齊送入糖化鍋中糖化50min后，再經(jīng)二級噴淋冷卻，將糖化醪冷卻到30℃，送入發(fā)酵工段進(jìn)行發(fā)酵。 b發(fā)酵采用間歇式發(fā)酵，為了配合連續(xù)蒸煮、糖化車間的操作，該設(shè)計曹勇連續(xù)添加法。生產(chǎn)開始時，先將一定量的酒母打入發(fā)酵罐，然后根據(jù)生產(chǎn)，確定流加速度。一般從接種酵母后，應(yīng)于6—8小時內(nèi)將罐裝滿。 連續(xù)流加法大發(fā)酵總時間自加滿罐時算起，需70小時左右發(fā)酵即結(jié)束。 C發(fā)酵成熟醪中的雜質(zhì)分為揮發(fā)性雜質(zhì)和不揮發(fā)性雜質(zhì)。不揮發(fā)性雜質(zhì)容易和酒精分離，在粗餾塔的底部排出，稱之為酒糟；揮發(fā)性雜質(zhì)按化學(xué)性質(zhì)又可分為四大類：醇類、醛類、脂類和酸類。另外還有一些微量的含硫物質(zhì)和不飽和化合物等，隨酒精一起從粗餾塔的頂部排出，進(jìn)入精餾塔進(jìn)行下一步分離。 蒸餾系統(tǒng)采用氣相進(jìn)塔的兩塔流程。發(fā)酵成熟醪用泵自發(fā)酵罐進(jìn)入預(yù)熱器，與精餾塔頂來的乙醇蒸氣進(jìn)行熱交換，成熟醪被加熱至40℃左右，再經(jīng)酒糟預(yù)熱器加熱至70℃左右，從粗餾塔頂部進(jìn)入粗餾塔。粗餾塔頂部用蒸汽直接加熱，使塔底溫度為105—108℃，塔斧壓力為19.6—24.5Kpa,塔頂溫度為92—95℃，塔頂約50％（體積分?jǐn)?shù)）的乙醇蒸汽直接進(jìn)入精餾塔，被蒸盡的成熟醪自塔底自動排出。 粗乙醇從蒸餾塔的中部進(jìn)料，塔斧溫度為102—104℃，塔斧壓力為13.7—15.7Kpa;進(jìn)入分凝器前塔頂乙醇蒸汽溫度為78—79℃，第二分凝器進(jìn)入第三分凝器的溫度為35—40℃。 雜醇油的提?。罕驹O(shè)計采用液相提取，即在進(jìn)料層之上2—4層塔板，溫度為85—92℃的區(qū)域中提取。 成品乙醇的提?。簽榱颂岣叱善芬掖嫉馁|(zhì)量，本設(shè)計采用從塔頂向下第3—6層塔板上提取。 為了提取雜質(zhì)中的甲醇，提高成品乙醇的質(zhì)量，由于95％（體積分?jǐn)?shù)）乙醇中，甲醇的揮發(fā)系數(shù)很大，在本設(shè)計采用適當(dāng)提高提高第二分凝器的溫度的方法來降低成品乙醇中甲醇的含量。 4 設(shè)計工作中面臨的技術(shù)難點和擬采取的解決方法 乙醇生產(chǎn)屬于危險化學(xué)品生產(chǎn)，其蒸氣與空氣可形成爆炸性混合物。遇明火、高熱能引起燃燒爆炸。與氧化劑接觸發(fā)生化學(xué)反應(yīng)或引起燃燒。在火場中，受熱的容器有爆炸危險。在設(shè)計時需考慮各種危險因素。精餾生產(chǎn)裝置、乙醇罐區(qū)均是易燃易爆場所，因而這些地區(qū)應(yīng)嚴(yán)密監(jiān)控，這些地方應(yīng)安裝可燃?xì)怏w檢測報警裝置，防火堤，自動滅火裝置以及其他消防設(shè)施。在乙醇的生產(chǎn)過程中會產(chǎn)生乙醇濃度不高現(xiàn)象，因此本設(shè)計采用汽相二塔蒸餾系統(tǒng)，從粗餾塔出來的粗乙醇從精餾塔的中部進(jìn)料，雜醇油的提取，本設(shè)計采用液相提取，即在進(jìn)料層之上2—4層塔板，溫度為85—92℃的區(qū)域中提取。醇的提為了提高成品乙醇的質(zhì)量，本設(shè)計采用從塔頂向下第3—6層塔板上提取。為了提取雜質(zhì)中的甲醇，提高成品乙醇的質(zhì)量，由于95％（體積分?jǐn)?shù)）乙醇中，甲醇的揮發(fā)系數(shù)很大，在本設(shè)計采用適當(dāng)提高提高第二分凝器的溫度的方法來降低成品乙醇中甲醇的含量。 5 已進(jìn)行的設(shè)計工作基礎(chǔ)和已具備的科學(xué)研究條件 大學(xué)期間學(xué)習(xí)的關(guān)于化學(xué)工程類的知識以及多次的化工設(shè)計的經(jīng)驗可以完成本設(shè)計；在圖書館、數(shù)據(jù)庫已經(jīng)進(jìn)行了相關(guān)的資料的收集工作；查找到了氣象條件，確定了廠址。 6 設(shè)計階段的進(jìn)度、要求，以及預(yù)期結(jié)果 周 次 設(shè)計（論文）任務(wù)及要求 1～3 熟悉題目、收集資料。 4～6 到有關(guān)廠參觀并收集有關(guān)參數(shù)。 6～10 工藝計算、設(shè)備選型、投資概算。 11～14 繪制各種圖紙。 15～17 撰寫設(shè)計說明書。 18 用三天時間準(zhǔn)備答辯。 7 參考文獻(xiàn) [1] 華東理工大學(xué)化工原理教研室編. 化工過程設(shè)備及設(shè)計. 廣州：華南理工大學(xué)出版社. 1996.02 [2] 天津大學(xué)化工原理教研室編. 化工原理（下). 天津：天津大學(xué)出版社 1999.04 [3] 吳思方主編. 發(fā)酵工廠設(shè)計概論 北京：中國輕工業(yè)出版社 1995.9 [4] 華南工學(xué)院等編. 發(fā)酵工程與設(shè)備. 輕工業(yè)出版社 1981 [5] 黃露，王保國等編. 化工設(shè)計 北京：化學(xué)工業(yè)出版社 2001.2 [6] 賈樹彪 ,李盛賢. 吳國峰編新編酒精工藝學(xué) 北京：工業(yè)出版社，1995 5 Fueling America Through Renewable Resources BioEnergy Purdue e x tension How Fuel e thanol is Made from Corn Nathan S. Mosier and Klein Ileleji Department of Agricultural and Biological Engineering Purdue University ID-328 Introduction Fuel ethanol has become a very important agricultural product over the past two decades. In 2005, more than 13% of U.S. corn production went toward making this fuel additive/fuel extender, which lessens U.S. dependence on foreign oil imports, is cleaner for the environment, and has substantial impact on the rural economy and agriculture production. Fuel Ethanol Ethanol is an alcohol produced by yeast from sugars. It is the same alcohol pro- duced by yeast in beer, wine, and spirits. Fuel ethanol is ethanol that has been highly concentrated to remove water and blended with other compounds to render the alcohol undrinkable. Fuel ethanol can be used alone as a fuel, such as in Indy Racing League cars, or can be blended with gasoline and used as fuel. All cars and trucks on the road today can use gasoline/ethanol blends of up to 10% ethanol (90% gasoline), also called “E10.” Blends of up to 85% ethanol, also known as “E85,” can be used as transportation fuel by cars and trucks with slight modifi- cations (approximately $100 per vehicle). These flexible fuel vehicles can use either gasoline or ethanol blends, including E85. Yeasts Role in Ethanol Production All ethanol production is based upon the activity of yeast (Saccharomyces cerevisiae), an important microorganism to humans. Through a process called “fermentation, ” yeast eat simple sugars and produce carbon dioxide (CO 2 ) and ethanol as waste products. For each pound of simple sugars, yeast can produce approximately pound (0.15 gallons) of ethanol and an equivalent amount of carbon dioxide. Corn as Ethanol Feedstock In 2005, approximately 11 billion bushels of corn were produced in the U.S. Indiana corn production in 2005 was approxi- mately 889 million bushels (USDA, 2006). Ethanol production in the U.S. topped 4 Fueling America Through Renewable Crops BioEnergy billion gallons in 2005 and con- sumed 1.4 billion bushels of corn, valued at $2.9 billion (NCGA, 2005). This represents the third largest demand for U.S. corn after animal feed and export markets. With additional construction of ethanol plants and increasing ethanol demand, fuel ethanol pro- duction is expected to exceed 7.5 billion gallons before the year 2012 target set forth in the Energy Policy Act of 2005 (EPACT05). The value of corn as a feedstock for ethanol production is due to the large amount of carbohydrates, specifically starch, present in corn (Table 1). Starch can be rather easily processed to break it down into simple sugars, which can then be fed to yeast to produce ethanol. Modern ethanol pro- duction can produce approximately 2.7 gallons of fuel ethanol per bushel of corn. Industrial Ethanol Production Commercial production of fuel ethanol in the U.S. involves breaking down the starch present in corn into simple sugars (glucose), feeding these sugars to yeast (fermentation), and then recovering the main prod- uct (ethanol) and byproducts (e.g., animal feed). Two major industrial methods for producing fuel ethanol are used in the U.S.: wet milling and dry grind. Dry- grind ethanol production represents the majority of ethanol processing in the U.S. ( 70% of production), and all newly constructed ethanol plants employ some variation on the basic dry-grind process because such plants can be built at a smaller scale for a smaller investment. Wet Milling Wet milling is used to produce many products besides fuel ethanol. Large-scale, capital-intensive, corn- processing wet mills produce such varied products as high fructose corn syrup (HFCS), biodegradable plastics, food additives such as citric acid and xanthan gum, corn oil (cooking oil), and livestock feed. Component Percent (average) Dry Matter Carbohydrates (total) 84.1% Starch 72.0% Fiber (NDF) 9.5% Simple Sugars 2.6% Protein 9.5% Oil 4.3% Minerals 1.4% Other 0.7% Table 1. Composition of Corn (from Corn: Chemistry and Technology, 1987) Wet milling is called “wet” because the first step in the process involves soaking the grain in water (steep- ing) to soften the grain and make it easier to separate (fractionate) the various components of the corn kernel. Fractionation, which separates the starch, fiber, and germ, allows these various components to be processed separately to make a variety of products. The major byproducts of wet-mill ethanol production are two animal feed products, corn gluten meal (high protein, 40%) and corn gluten feed (low protein, 28%), and corn germ, which may be further processed into corn oil. Dry Grind In the dry-grind ethanol process, the whole grain is processed, and the residual components are separated at the end of the process. There are five major steps in the dry-grind method of ethanol production. dry-Grind e thanol Processing s teps 1. Milling 2. Liquefaction 3. Saccharification 4. Fermentation 5. Distillation and recovery Milling Milling involves processing corn through a hammer mill (with screens between 3.2 to 4.0 mm) to produce Purdue e xtension How Ethanol Is Made from Corn ID-328 a corn flour (Rausch et al., 2005). This whole corn flour is slurried with water, and heat-stable enzyme ( a-amylase) is added. Liquefaction This slurry is cooked, also known as “l(fā)iquefaction. ” Liquefaction is accomplished using jet-cookers that inject steam into the corn flour slurry to cook it at temperatures above 100C (212F). The heat and me- chanical shear of the cooking process break apart the starch granules present in the kernel endosperm, and the enzymes break down the starch polymer into small fragments. The cooked corn mash is then allowed to cool to 80-90C (175-195F), additional enzyme ( a-amylase) is added, and the slurry is allowed to con- tinue liquefying for at least 30 minutes. Saccharification After liquefaction, the slurry, now called “corn mash, ” is cooled to approximately 30C (86F), and a second enzyme (glucoamylase) is added. Glucoamylase com- pletes the breakdown of the starch into simple sugar (glucose). This step, called “saccharification, ” often oc - curs while the mash is filling the fermentor in prepa- ration for the next step (fermentation) and continues throughout the next step. Fermentation In the fermentation step, yeast grown in seed tanks are added to the corn mash to begin the process of con- verting the simple sugars to ethanol. The other com- ponents of the corn kernel (protein, oil, etc.) remain largely unchanged during the fermentation process. In most dry-grind ethanol plants, the fermentation pro- cess occurs in batches. A fermentation tank is filled, and the batch ferments completely before the tank is drained and refilled with a new batch. The up-stream processes (grinding, liquefaction, and saccharification) and downstream processes (distil- lation and recovery) occur continuously (grain is continuously processed through the equipment). Thus, dry-grind facilities of this design usually have three fermentors (tanks for fermentation) where, at any given time, one is filling, one is fermenting (usually for 48 hours), and one is emptying and resetting for the next batch. Carbon dioxide is also produced during fermenta- tion. Usually, the carbon dioxide is not recovered and is released from the fermenters to the atmosphere. If recovered, this carbon dioxide can be compressed and sold for carbonation of soft drinks or frozen into dry ice for cold product storage and transportation. After the fermentation is complete, the fermented corn mash (now called “beer”) is emptied from the fermentor into a beer well. The beer well stores the fer- mented beer between batches and supplies a continu- ous stream of material to the ethanol recovery steps, including distillation. Distillation and Recovery After fermentation, the liquid portion of the slurry has 8-12% ethanol by weight. Because ethanol boils at a lower temperature than water does, the ethanol can be separated by a process called “distillation. ” Conventional distillation/rectification systems can produce ethanol at 92-95% purity. The residual water is then removed using molecular sieves that selectively adsorb the water from an ethanol/water vapor mix- ture, resulting in nearly pure ethanol (99%). The residual water and corn solids that remain after the distillation process are called “stillage. ” This whole stillage is then centrifuged to separate the liquid (thin stillage) from the solid fragments of the kernel (wet cake or distillers grains). Some of the thin stillage (backset) is recycled to the beginning of the dry-grind process to conserve the water used by the facility. The remaining thin stillage passes through evaporators to remove a significant portion of the water to produce thickened syrup. Usually, the syrup is blended with the distillers grains and dried to produce an animal feed called “distillers dried grains with solubles” (DDGS). When markets for the feed product are close to the plant, the byproduct may be sold without drying as distillers grains or wet distillers grains. Energy Use in Ethanol Production It is true that the laws of physics dictate that energy will be lost in converting one form of energy to an- other. Thus, ethanol does have less energy than the corn used to produce it. However, this is also true for converting crude oil to gasoline and coal to electricity. The important questions about ethanol production are “is ethanol truly a renewable fuel?” and “how much fossil fuel is used?” Fueling America Through Renewable Crops BioEnergy Purdue AGri Culture NEW 12/06 It is the policy of the Purdue University Cooperative Extension Service, David C. Petritz, Director, that all persons shall have equal opportunity and access to the programs and facilities without regard to race, color, sex, religion, national origin, age, marital status, parental status, sexual orientation, or disability. Purdue University is an Affirmative Action institution. This material may be available in alternative formats. 1-888-EXT-INFO http:/www.ces.purdue.edu/new Y es; ethanol is a renewable fuel. The energy used to produce ethanol includes fuel for tractors, combines, and transportation of the grain to the ethanol plant, as well as the energy in processing the corn to ethanol. However, the largest portion of the total energy pres- ent in corn is solar energy captured by the corn plant and stored in the grain as starch. When these amounts are totaled, the energy in the ethanol exceeds the fossil fuel energy used to grow and process the corn by 20 to 40% (Farrell et al., 2006). Most of the energy for processing corn to ethanol is spent on the distillation and DDGS drying steps of the process. When wet distillers grain can be fed to live- stock close to the ethanol plant, the savings in natural gas for drying can be as high as 20% of the total energy cost for processing corn to ethanol. Conclusions Modern dry-grind ethanol plants can convert corn grain into ethanol (2.7-2.8 gallons per bushel) and DDGS (17 pounds per bushel). This rather energy- efficient process produces a renewable liquid fuel that has significant impacts on the agricultural economy and energy use in the U.S. Increasing ethanol production presents many oppor- tunities and challenges for U.S. agriculture as demands on corn production for feed, fuel, and export markets increase. Additionally, advances in biotechnology and engineering are opening possibilities for new raw materials, such as switch grass and corn stover, to be used for even greater fuel ethanol production into the future. References and Links to Further Information Farrell, A. E.; Plevin, R. J.; Turner, B. T.; Jones A. D.; OHare, M.; Kammen, D. M. “Ethanol Can Contribute to Energy and Environmental Goals, ” Science 311(5760): 506 508, (2006). National Corn Growers Association (NCGA) Annual Report (2005). Purdue Laboratory of Renewable Resources Engineering . Rausch, K. D.; Belyea, R. L.; Ellersieck, M. R.; Singh, V .; Johnston, D. B.; Tumbleson, M. E. “Particle Size Distributions of Ground Corn and DDGS From Dry Grind Processing, ” Transactions of the ASAE, 48(1):273277, (2005). U.S. Department of Agriculture, National Agriculture Statistics Service . Watson, S. A., “Structure and Composition, ” Corn: Chemistry and Technology, Watson, S. A. and Ramstad, P . E. (eds). American Association of Cereal Chemists, Inc. pp 53-82, (1987). Visit for free, downloadable copies of all of the publications in the Purdue Extension BioEnergy series.