【正文】 ,還可降低氣霧劑中乙醇及其它有機(jī)揮發(fā)物的含量,減少對(duì)環(huán)境的污染。總之,二甲醚在儲(chǔ)存、運(yùn)輸、使用等方面比 LPG 更安全?？諝庵性试S濃度為 400ppm[1]。與空氣混合能形成爆炸性混合物。以保證精餾過程的順利進(jìn)行并使效率盡可能的提高。二甲醚的制備主要有甲醇脫水法和合成氣一步法兩種。與傳統(tǒng)的甲醇合成二甲醚相比，一步法合成二甲醚工藝經(jīng)濟(jì)更加合理，在市場(chǎng)更具有競(jìng)爭(zhēng)力，正在走向工業(yè)化。關(guān)鍵詞：二甲醚 分離 三元體系 精餾II / 53Annual output of 30,000 tons of dimethyl ether distillation section in the design of separation deviceABSTRACTIn recent years, DME has bee an alternative channel of international oil and new secondary energy and hot topics, That aroused national concern and attention.Preparation of dimethyl ether mainly methanol dehydration and Onestep synthesis. With the traditional methanol synthesis pared to synthesis of dimethyl ether, onestep synthesis of dimethyl ether process more rational economy, more petitive in the market and it is moving towards industrialization. Currently, synthesis gas to dimethyl ether is the latest technology Preparation of dimethyl ether. Compared with methanol dehydration, system of direct synthesis of DME as the existence of unreacted synthesis gas and carbon dioxide finished. If it want to get high purity dimethyl ether, more plicated separation process. Developed mainly in the separation process such as chemical absorption and distillation unit operation in the process of dimethyl ether with higher purity product. This design aimed at separating the distillation process for process design, separation of dimethyl ether, methanol and water ternary system. Design of distillation towers used valve. Use the whole top of the tower condenser cooling device used to accurately control the reflux ratio. Bottom of the column of steam heating by steam to provide sufficient heat. Obtained by calculating the number of theoretical plates, tower efficiency, the actual plate number, feed location. The main tower in the plate design and calculation of process dimensions derived column diameter, the effective tower, sieve number. Checking through the sieve of fluid mechanics, to prove that the indicator data are in line with standards to ensure the smooth progress of distillation process and to improve efficiency as much as possibleKeywords: DME separate ternary system distillationIII / 53目 錄摘 要.....................................................IABSTRACT................................................II1 緒論..................................................1 概述 .....................................................1 設(shè)計(jì)依據(jù) ...............................................1 設(shè)計(jì)規(guī)模及設(shè)計(jì)要求 .....................................1 產(chǎn)品規(guī)格、性質(zhì)及用途 ...................................1 技術(shù)來源 ...............................................3 二甲醚分離裝置流程 .......................................62 精餾塔的工藝計(jì)算.......................................8 精餾塔的物料衡算 .........................................8 基礎(chǔ)數(shù)據(jù) ...............................................8 物料衡算 ...............................................8 精餾塔工藝計(jì)算 ..........................................10 物料衡算 ..............................................10 操作條件的確定 ........................................10 精餾塔設(shè)備計(jì)算 ..........................................12 基礎(chǔ)數(shù)據(jù) ..............................................12 塔板數(shù)的確定 ..........................................15 精餾塔主要尺寸計(jì)算 ....................................18 塔板結(jié)構(gòu)設(shè)計(jì) ..........................................21 塔板流體力學(xué)驗(yàn)算 ......................................26 塔板負(fù)荷性能圖 ........................................29 塔高的計(jì)算 ............................................333 熱量衡算..............................................35 數(shù)據(jù) ....................................................35IV / 53 冷凝器的熱負(fù)荷 ..........................................35 再沸器的熱負(fù)荷 ..........................................36 冷卻水消耗量和加熱蒸汽消耗量 ............................384 主要設(shè)備設(shè)計(jì)和選型 ....................................39 接管的設(shè)計(jì) ..............................................39 進(jìn)料管 ................................................39 回流管 ................................................39 釜液出口管 ............................................39 塔頂蒸汽管 ............................................40 加熱蒸汽管 ............................................40 冷凝器的選型 ............................................415 結(jié)論..................................................42參考文獻(xiàn)................................................43附錄....................................................44謝辭....................................................461 / 531 緒論 概述 設(shè)計(jì)依據(jù)根據(jù)北京理工大學(xué)珠海學(xué)院下達(dá)的設(shè)計(jì)任務(wù)書，模擬現(xiàn)有的漿態(tài)床一步法二甲醚合成產(chǎn)業(yè)化技術(shù)，對(duì)二甲醚分離裝置中的精餾工段進(jìn)行工藝設(shè)計(jì)。接觸熱、火星、火焰或氧化劑易燃燒爆炸。二甲醚的物理性質(zhì)見表 11 [2]2 / 53表 11 二甲醚的物理性質(zhì)項(xiàng)目 數(shù)值 項(xiàng)目 數(shù)值沸點(diǎn)()/℃ 蒸氣壓(20℃)/MPa 熔點(diǎn)/℃ 燃燒值(氣壓)/kJ*mol 11455閃點(diǎn)(開杯法) /℃ 生成熱(氣態(tài))/ kJ*mol1密度(20℃)/g*ml1 熔融熱/ kJ*mol 1 臨界壓力/MPa 蒸發(fā)熱/ kJ*mol 1 臨界溫度/℃臨界密度/ g*ml1生成自由能/ kJ*mol 125℃熵/J/(mol*K)自燃溫度/℃ 350 蒸氣密度/kg*m 3 ~(三) 二甲醚的用途(1) 用作燃料二甲醚可替代液化石油氣(LPG)作為燃料。因此二甲醚代替 LPG 作為優(yōu)良的民用潔凈燃料,具有廣闊的前景。目前在國(guó)外,二甲醚在民用氣溶膠制品中已是必不可少的氯氟烴替代物。 [4] 技術(shù)來源(一) 合成技術(shù)來源DME 的制備主要有甲醇脫水法和合成氣一步法兩種。該工藝成熟簡(jiǎn)單 ,對(duì)設(shè)備材質(zhì)無特殊要求，基本無三廢及設(shè)備腐蝕問題，后處理簡(jiǎn)單。 [6]①固定床法固定床法即為氣相法，合成氣在固體催化劑表面進(jìn)行反應(yīng)；在氣相法工藝中，使用貧氫合成氣為原料氣時(shí)，催化劑表面會(huì)很快積炭，因此往往需要富氫合成氣為原料氣。 [9]由合成氣直接合成 DME,與甲醇?xì)庀嗝撍ㄏ啾?具有流程短、投資省、能耗低等優(yōu)點(diǎn) ,而且可獲得較高的單程轉(zhuǎn)化率。一種分離工藝是一步反應(yīng)后產(chǎn)物分為氣液兩相。含有不凝氣體HCO 、CO 2 和少量惰性氣體和 CH4 及未冷凝的二甲醚氣體的未凝氣體 16 經(jīng)減壓到 ，進(jìn)入吸收塔 2 下部，在 MPa，在 2035℃下用軟水吸收，冷凝器 1 的底流產(chǎn)物粗二甲醚溶液 7 和吸收塔 2 的底流產(chǎn)物醚水溶液 8 進(jìn)入閃蒸罐 3，閃蒸罐的溫度為 40100℃。吸收塔尾氣 15去變壓吸附或膜分離提取有用成份 CO、H 2后，返回二甲醚合成單元做合成原料。B?塔頂： )()()( 2???DSBADABPK進(jìn)料： ..83)()()( 34FSBAFFAB?)()()( 3???FSBCFFCBPK塔釜： )()()( 34WSBAWAB?)()()( 3???SBCCBPK全塔平均相對(duì)揮發(fā)度： ..6一般 how 不應(yīng)小于 6mm,以免液體在堰上分布不均。一般 how 不應(yīng)小于 6mm,以免液體在堰上分布不均。因此，氣體流經(jīng)一層浮閥塔板的壓強(qiáng)降所相當(dāng)?shù)囊褐叨葹椋壕s段： )(. mhcp ?????提餾段： ...???單板壓降：精餾段： (Pa). ????ghpL?提餾段： .???(二) 淹塔為防止淹塔現(xiàn)象的發(fā)生，要求控制降液管中清液層高度 )(WTdH???， dLpdh??(1) ：氣體通過塔板的壓強(qiáng)降所相當(dāng)?shù)囊褐叨萷h(2) ：板上液層高度L(3) ：液體通過降液管的壓頭損失d不設(shè)進(jìn)口堰，按 計(jì)算：2)(?精餾段： m)().58910743(.)(. 22 ??oSdl