楊德明,顧強(qiáng),朱碧云,王爭(zhēng)光,印一凡,高曉新
(常州大學(xué)石油化工學(xué)院,江蘇 常州 213164)
基于有機(jī)朗肯循環(huán)的混合二甲苯MVR熱泵精餾工藝
楊德明,顧強(qiáng),朱碧云,王爭(zhēng)光,印一凡,高曉新
(常州大學(xué)石油化工學(xué)院,江蘇 常州 213164)
常規(guī)機(jī)械蒸氣再壓縮(MVR)熱泵精餾分離混合二甲苯工藝,存在壓縮機(jī)電耗較大及塔頂壓縮蒸氣的顯熱未被利用等問(wèn)題。有機(jī)朗肯循環(huán)(ORC)發(fā)電技術(shù)則可以將低溫余熱轉(zhuǎn)化為電能以供壓縮機(jī)使用,由此提出了ORC發(fā)電技術(shù)耦合MVR熱泵和帶乏汽回?zé)嵫h(huán)(EGC)的ORC發(fā)電技術(shù)耦合MVR熱泵兩種精餾工藝應(yīng)用于本體系的分離研究。以年總費(fèi)用(TAC)和能耗為分離工藝的評(píng)價(jià)指標(biāo),系統(tǒng)凈輸出功和循環(huán)熱效率作為ORC系統(tǒng)的評(píng)價(jià)指標(biāo),對(duì)以上兩種耦合精餾工藝進(jìn)行模擬與優(yōu)化,并與常規(guī)MVR熱泵精餾工藝進(jìn)行比較與分析。研究結(jié)果表明,ORC發(fā)電技術(shù)耦合MVR熱泵精餾工藝和帶EGC的ORC發(fā)電技術(shù)耦合MVR熱泵精餾工藝較常規(guī)MVR熱泵精餾工藝均具有一定的節(jié)能和經(jīng)濟(jì)優(yōu)勢(shì),可分別減少能耗9.64%和9.89%,節(jié)省TAC 3.19%和3.50%。
混合二甲苯;MVR熱泵;有機(jī)朗肯循環(huán);精餾;計(jì)算機(jī)模擬;能耗;年總費(fèi)用
對(duì)于鄰二甲苯(OX)、間二甲苯(MX)、對(duì)二甲苯(PX)和乙苯(EB)混合物的分離,常規(guī)MVR熱泵精餾工藝可以大幅度降低其分離能耗[1]。但混合二甲苯的常規(guī)MVR熱泵精餾工藝中,由于塔的操作壓力低于壓縮蒸氣的壓力,為防止回流液入塔的閃蒸汽化現(xiàn)象,壓縮蒸氣經(jīng)換熱后得到的高溫高壓飽和液體不能直接進(jìn)入塔內(nèi)回流,需要經(jīng)過(guò)一個(gè)減壓放熱過(guò)程,通常情況下這部分熱量用冷卻水冷卻,造成了熱量的不可逆損失[2-3]。再者,常規(guī)MVR熱泵精餾工藝消耗的電能全部需要依賴于外界,電耗較大。
有機(jī)朗肯循環(huán)(organic Rankine cycle,ORC)是以低沸點(diǎn)有機(jī)物為工質(zhì)的朗肯循環(huán)[4-11],有機(jī)工質(zhì)在換熱器中從余熱流中吸收熱量,生成具一定壓力和溫度的蒸氣,蒸氣進(jìn)入透平機(jī)械膨脹做功,從而帶動(dòng)發(fā)電機(jī)發(fā)電。而在有機(jī)朗肯循環(huán)中,乏汽進(jìn)入凝汽器,在凝結(jié)過(guò)程中被循環(huán)水帶走。為減少凝汽器中被冷卻水所帶走的熱量,采用乏汽先預(yù)熱工質(zhì)后冷凝冷卻的熱力循環(huán),即乏汽回?zé)嵫h(huán)(EGC)[12-13],可以達(dá)到大幅度利用熱量的目的。鑒于常規(guī) MVR熱泵精餾工藝存在的以上不足及ORC的優(yōu)勢(shì),本文把ORC和EGC技術(shù)應(yīng)用于本體系的MVR熱泵精餾工藝,研究其進(jìn)一步節(jié)能的可行性,預(yù)期找到一條更為經(jīng)濟(jì)的精餾工藝路線。
規(guī)定混合二甲苯處理量為25 kmol·h-1,其中EB含量為 0.17(質(zhì)量分?jǐn)?shù),下同)、PX為 0.18、MX為0.4、OX為0.25。要求4種組分的純度均不低于0.98。精餾塔頂采用冷卻水冷凝,冷卻水的進(jìn)出口溫度規(guī)定為33℃和39℃;塔底采用0.3 MPa的飽和水蒸氣供熱。ORC中冷凝器采用冷水冷卻,該部分冷水的進(jìn)出口溫度規(guī)定為20℃和25℃。本體系精餾部分選用軟件中的 RK-Soave狀態(tài)方程計(jì)算汽液相平衡數(shù)據(jù)[14],ORC系統(tǒng)選用發(fā)電系統(tǒng)常用的Peng-Robinson狀態(tài)方程[15]模擬計(jì)算。
評(píng)價(jià)一個(gè)工藝過(guò)程的優(yōu)劣,不僅要考慮其操作費(fèi)用,同時(shí)還要考慮其投資成本。因此本文以綜合經(jīng)濟(jì)效益,即年總費(fèi)用TAC(total annual cost)為評(píng)價(jià)指標(biāo),TAC由操作費(fèi)用和設(shè)備投資費(fèi)用構(gòu)成。操作費(fèi)用包括加熱蒸氣費(fèi)用(α)、冷卻水費(fèi)用(β)和壓縮機(jī)用電費(fèi)用(γ)。由于設(shè)備分為靜設(shè)備(如塔器、換熱器等)和動(dòng)設(shè)備(如壓縮機(jī)、透平以及發(fā)電機(jī)等),靜設(shè)備的運(yùn)行維護(hù)費(fèi)用很小,在計(jì)算TAC時(shí),只考慮其設(shè)備本身的投資費(fèi)用;而對(duì)于動(dòng)設(shè)備,還考慮了其運(yùn)行維護(hù)等費(fèi)用(按動(dòng)設(shè)備總投資額的 10%計(jì)),具體計(jì)算見(jiàn)式(5)。規(guī)定所有設(shè)備的使用年限為 5a,年工作時(shí)為 7200 h。則各項(xiàng)計(jì)算公式[16-18]如下
ORC系統(tǒng)以輸出凈功Wexp和系統(tǒng)循環(huán)熱效率ηORC作為評(píng)價(jià)指標(biāo),凈輸出功為膨脹機(jī)對(duì)外做功WT與循環(huán)泵消耗功WP的差,計(jì)算公式[19-24]如下
則ORC系統(tǒng)的發(fā)電量GMORC為
對(duì)于MVR熱泵系統(tǒng),以熱泵的循環(huán)性能系數(shù)COP作為評(píng)價(jià)指標(biāo),COP定義為輸出的制熱量(Qout)與蒸氣壓縮機(jī)輸入功率(Win)的比率,計(jì)算公式[25-26]如下
根據(jù)前期的研究結(jié)果[1],采用如圖1所示的常規(guī)MVR熱泵精餾工藝(帶虛線的為輔助再沸器,下同),該工藝依次分出OX、EB、PX和MX,優(yōu)化后的模擬結(jié)果見(jiàn)表1。
由表1數(shù)據(jù)可知,常規(guī)MVR熱泵精餾工藝分離混合二甲苯,壓縮機(jī)電耗較大,且三塔壓縮蒸氣冷后移熱(顯熱)總量高達(dá)1746.17 kW,這部分熱量由冷卻水冷卻,造成了能量的大量浪費(fèi)和不可逆性。為此,引入 ORC低溫發(fā)電技術(shù),以供壓縮機(jī)本身使用,由此可以達(dá)到大幅度減少壓縮機(jī)電耗的目的。
圖1 MVR熱泵精餾工藝Fig.1 MVR heat pump distillation process
表1 MVR熱泵精餾工藝模擬結(jié)果Table 1 Simulation results of MVR heat pump distillation process
影響ORC系統(tǒng)效能的主要因素為工質(zhì)的選擇、蒸發(fā)器出口工質(zhì)的過(guò)熱度、蒸發(fā)壓力、冷凝器出口工質(zhì)的過(guò)冷度和冷凝壓力等。為了便于計(jì)算分析,膨脹機(jī)的等熵效率設(shè)為 0.85,增壓泵的效率設(shè)為0.9,發(fā)電機(jī)效率為0.95[27]。
以T1塔為例,其ORC耦合MVR熱泵精餾工藝見(jiàn)圖2。T1塔塔頂蒸氣經(jīng)壓縮機(jī)(COMP)壓縮后與塔釜液相在再沸器中換熱后冷凝成高壓飽和液相,進(jìn)入蒸發(fā)器(EVA)被有機(jī)冷工質(zhì)冷卻后部分回流,部分采出。而有機(jī)工質(zhì)則在其中蒸發(fā)成氣相進(jìn)入膨脹機(jī)(TURB)發(fā)電,以供系統(tǒng)內(nèi)的壓縮機(jī)(COMP)使用,由此可以減少壓縮機(jī)的電耗。而膨脹機(jī)出口乏汽則進(jìn)入冷凝器(CON)冷凝冷卻后經(jīng)增壓泵(PUMP)返回EVA內(nèi)循環(huán)使用。
圖2 ORC耦合MVR熱泵精餾工藝流程(T1塔)Fig.2 MVR heat pump distillation coupled by ORC process for T1 tower
2.2.1 循環(huán)工質(zhì) ORC系統(tǒng)的能效與工質(zhì)關(guān)系很大,本文選取5種ORC系統(tǒng)常用的有機(jī)工質(zhì)[28-31]進(jìn)行研究,最終根據(jù)系統(tǒng)凈輸出功和循環(huán)熱效率,篩選最優(yōu)的有機(jī)工質(zhì)作為本體系的循環(huán)工質(zhì)。5種有機(jī)工質(zhì)分別為 R113、R123、R245fa、R600a和R601a,具體性質(zhì)見(jiàn)表2。
表2 5種有機(jī)工質(zhì)基本性質(zhì)Table 2 Basic properties of five organic working fluids
由表2可知,5種工質(zhì)標(biāo)準(zhǔn)沸點(diǎn)與熱源溫度(82℃)相比均較低,臨界溫度也高于循環(huán)中的最高溫度。5種工質(zhì)的 GWP(全球變暖系數(shù)值)和 ODP(破壞臭氧潛能值)均較小,汽化潛熱較大,符合ORC循環(huán)工質(zhì)的基本要求。
2.2.2 過(guò)熱度對(duì)系統(tǒng)性能的影響 為研究蒸發(fā)器出口工質(zhì)的過(guò)熱度對(duì)系統(tǒng)性能的影響,規(guī)定冷凝器出口工質(zhì)過(guò)冷度為0℃,蒸發(fā)壓力為0.2 MPa,膨脹機(jī)的膨脹比為0.4。以工質(zhì)R123和T1塔的熱泵熱源為例,通過(guò)模擬,考察過(guò)熱度與系統(tǒng)凈輸出功和熱效率的變化趨勢(shì),結(jié)果見(jiàn)圖3。
圖3 過(guò)熱度對(duì)系統(tǒng)凈輸出功和熱效率的影響Fig.3 Effect of superheat on net output power and thermal efficiency
由圖3可以看出,蒸發(fā)器出口工質(zhì)過(guò)熱度越高,系統(tǒng)凈輸出功與熱效率均越低。其原因是蒸發(fā)器的吸熱量一定,過(guò)熱度的提高導(dǎo)致蒸發(fā)器入口工質(zhì)流量減少,減少的幅度大于膨脹機(jī)出入口焓降的變化,輸出功減少。蒸發(fā)器的吸熱量不變而系統(tǒng)對(duì)外輸出功減少,所以系統(tǒng)循環(huán)熱效率隨之降低。因此,設(shè)計(jì)系統(tǒng)時(shí)應(yīng)使過(guò)熱度降低,最好在飽和狀態(tài)下使工質(zhì)進(jìn)入膨脹機(jī),即過(guò)熱度為0℃。
2.2.3 過(guò)冷度對(duì)系統(tǒng)性能的影響 規(guī)定蒸發(fā)器出口工質(zhì)過(guò)熱度為0℃,其余條件保持不變,通過(guò)模擬,考察過(guò)冷度對(duì)整體系統(tǒng)性能的影響,結(jié)果見(jiàn)圖4。
圖4 過(guò)冷度對(duì)系統(tǒng)凈輸出功和熱效率的影響Fig.4 Effect of supercooling on net output power and thermal efficiency
由圖4可以看出,隨著過(guò)冷度的增加,系統(tǒng)凈輸出功和熱效率也同時(shí)呈現(xiàn)出下降的趨勢(shì)。其原因是過(guò)冷度增加,即蒸發(fā)器入口工質(zhì)溫度降低,為保持蒸發(fā)器吸熱量則工質(zhì)流量變小,膨脹機(jī)前后焓降不變,所以輸出功減少,而蒸發(fā)器吸熱量不變,循環(huán)熱效率也減小。因此,過(guò)冷度也應(yīng)盡量減小,最好在飽和狀態(tài)下進(jìn)入工質(zhì)增壓泵,即過(guò)冷度為0℃。
2.2.4 蒸發(fā)壓力對(duì)系統(tǒng)性能的影響 規(guī)定工質(zhì)過(guò)熱度和過(guò)冷度都為 0℃,其余條件保持不變,通過(guò)模擬考察系統(tǒng)的蒸發(fā)壓力與系統(tǒng)凈輸出功和熱效率的變化規(guī)律,結(jié)果見(jiàn)圖5。
圖5 蒸發(fā)壓力對(duì)系統(tǒng)凈輸出功和熱效率的影響Fig.5 Effect of evaporation pressure on net output power and thermal efficiency
由圖5可以看出,蒸發(fā)壓力增大,系統(tǒng)凈輸出功和熱效率都呈現(xiàn)上升的趨勢(shì)。因?yàn)檎舭l(fā)壓力升高,蒸發(fā)器內(nèi)工質(zhì)和熱源的傳熱溫差降低,為滿足換熱要求,則工質(zhì)流量增大,膨脹機(jī)做功增大,系統(tǒng)熱效率也隨之增大。但蒸發(fā)壓力也不能無(wú)限增大,蒸發(fā)壓力下的飽和氣相溫度仍需滿足與熱源換熱之間的傳熱溫差。因此蒸發(fā)壓力選擇0.4 MPa比較合適。
2.2.5 冷凝壓力對(duì)系統(tǒng)性能的影響 規(guī)定工質(zhì)的過(guò)熱度和過(guò)冷度都為0℃,蒸發(fā)壓力為0.4 MPa,保持以上條件不變,通過(guò)模擬考察膨脹機(jī)出口的冷凝壓力與系統(tǒng)凈輸出功和熱效率的變化規(guī)律,結(jié)果見(jiàn)圖6。
圖6 冷凝壓力對(duì)系統(tǒng)凈輸出功和熱效率的影響Fig.6 Effect of condensation pressure on net output power and thermal efficiency
由圖6可以看出,冷凝壓力下降,系統(tǒng)凈輸出功和熱效率隨之變大。因?yàn)槔淠龎毫ο陆?,冷凝器出口工質(zhì)溫度降低,蒸發(fā)器入口工質(zhì)溫度隨之降低,膨脹機(jī)出入口焓降變大幅度大于工質(zhì)流量變小幅度,導(dǎo)致凈輸出功和熱效率的上升。但是冷凝壓力也不能無(wú)限小,同時(shí)也要保證該壓力下工質(zhì)在冷凝器中可以由冷卻水進(jìn)行冷卻,否則將增加過(guò)多的操作費(fèi)用。因此,系統(tǒng)的冷凝壓力定為0.092 MPa。
綜上所述,以R123為循環(huán)工質(zhì)的ORC最優(yōu)工藝參數(shù)為:過(guò)熱度和過(guò)冷度都為0℃、蒸發(fā)壓力0.4 MPa、冷凝壓力0.092 MPa。同樣的方法得到另外4種工質(zhì)的最優(yōu)參數(shù),結(jié)果匯總見(jiàn)表3。
表3 不同工質(zhì)模擬結(jié)果匯總Table 3 Simulation results of different working fluids
表4 ORC耦合MVR精餾工藝結(jié)果匯總Table 4 Simulation results of MVR heat pump distillation coupled by ORC process
圖7為乏汽回?zé)嵫h(huán)(EGC)流程[32],EGC系統(tǒng)是膨脹機(jī)出口蒸氣在進(jìn)入冷凝器之前先經(jīng)過(guò)回?zé)崞鳎≧E-GEN),用于預(yù)熱從工質(zhì)泵(PUMP)出口進(jìn)入蒸發(fā)器的工質(zhì),該工藝充分利用了乏汽的潛熱,有利于提高工質(zhì)的蒸發(fā)效率,增加發(fā)電量。
回?zé)岫龋椿責(zé)崞髦泄べ|(zhì)吸熱量與膨脹機(jī)出口乏汽降至泵出口溫度時(shí)放出的熱量之比,thermal ratio)是影響乏汽回?zé)岬闹匾獏?shù)。在上述得到的R123循環(huán)工質(zhì)優(yōu)化參數(shù)條件下,以T1塔為例,通過(guò)模擬,考察了回?zé)岫葘?duì)系統(tǒng)性能的影響,圖8為回?zé)岫葘?duì)系統(tǒng)凈輸出功和熱效率的影響。
圖7 乏汽回?zé)峁べ|(zhì)循環(huán)流程Fig.7 Exhaust steam regenerative cycle process
圖8 回?zé)岫葘?duì)系統(tǒng)凈輸出功和熱效率的影響Fig.8 Effect of thermal ratio on net output power and thermal efficiency
由圖8可以看出,隨著回?zé)崞髦谢責(zé)岫鹊脑黾?,系統(tǒng)凈輸出功與熱效率均呈上升趨勢(shì)。其原因是回?zé)岫壬?,蒸發(fā)器入口工質(zhì)溫度升高,在保持膨脹機(jī)出入口焓降不變的條件下,可以增加工質(zhì)流量,從而增加膨脹機(jī)輸出功,因此系統(tǒng)凈輸出功與熱效率隨之增加。但回?zé)岫冗^(guò)高時(shí),蒸發(fā)器入口工質(zhì)溫度隨之過(guò)高,考慮到蒸發(fā)器的換熱溫差(一般取10℃左右),回?zé)岫炔粦?yīng)該超過(guò)0.027。同樣的方法,對(duì)T2和T3塔進(jìn)行優(yōu)化,得到相應(yīng)的最佳回?zé)岫葦?shù)據(jù)以及各工藝參數(shù),結(jié)果見(jiàn)表5??梢?jiàn),帶EGC的ORC耦合MVR精餾工藝較常規(guī)MVR精餾工藝節(jié)
表5 帶EGC的ORC耦合MVR精餾工藝結(jié)果匯總Table 5 Simulation results of MVR heat pump distillation process coupled by ORC combined with EGC process
上述各精餾工藝模擬結(jié)果匯總見(jiàn)表 6。從能耗和TAC來(lái)評(píng)價(jià),帶EGC的ORC耦合MVR精餾工藝是最優(yōu)的。因?yàn)樵摴に囋诔R?guī)ORC耦合MVR精餾工藝基礎(chǔ)上,充分利用了膨脹機(jī)出口乏汽的潛熱,增加了系統(tǒng)的凈輸出功。與常規(guī)MVR熱泵精餾工藝相比,ORC耦合MVR精餾工藝和帶EGC的ORC耦合MVR精餾工藝能耗分別減少9.64%和9.89%;而 TAC分別減少 3.19%和 3.50%。這是因?yàn)橐隣RC發(fā)電技術(shù)后,雖然節(jié)省了部分壓縮機(jī)的操作費(fèi)用,但由于增加了膨脹機(jī)和換熱器,導(dǎo)致設(shè)備費(fèi)用的加大,因此TAC減少的幅度并不大。
表6 各精餾工藝模擬結(jié)果匯總Table 6 Summary of simulation results of each distillation process
將有機(jī)朗肯循環(huán)(ORC)和乏汽回?zé)嵫h(huán)(EGC)技術(shù)應(yīng)用于混合二甲苯體系的MVR熱泵精餾工藝,通過(guò)模擬計(jì)算與優(yōu)化,得到如下結(jié)論。
(1)由于 ORC低溫余熱發(fā)電技術(shù)充分利用了壓縮蒸氣冷后的飽和液體余熱(顯熱),因而可以降低整個(gè)體系的分離能耗。本體系最合適的 ORC循環(huán)工質(zhì)為R123。
(2)ORC耦合MVR精餾工藝較常規(guī)的MVR熱泵精餾工藝節(jié)約能耗9.64 %,節(jié)省TAC 3.19%;而帶 EGC的 ORC耦合 MVR精餾工藝較常規(guī)的MVR熱泵精餾工藝節(jié)約能耗 9.89 %,節(jié)省TAC3.50%。
大數(shù)據(jù)分析計(jì)算平臺(tái)是基于Hadoop集群構(gòu)建的分布式計(jì)算平臺(tái),利用HDFS實(shí)現(xiàn)海量數(shù)據(jù)的存儲(chǔ)。為滿足綠通治理的業(yè)務(wù)需求,該平臺(tái)提供離線海量數(shù)據(jù)的分析計(jì)算和實(shí)時(shí)在線分析計(jì)算2種分析計(jì)算模式。
(3)對(duì)于常規(guī)的MVR熱泵精餾工藝,若塔的操作壓力低于壓縮蒸氣的飽和壓力,原則上以上兩種ORC耦合MVR熱泵精餾工藝均是可行的,而帶EGC的ORC耦合MVR精餾工藝更具經(jīng)濟(jì)優(yōu)勢(shì)。
(4)綜合考慮MVR熱泵的應(yīng)用場(chǎng)合、ORC余熱發(fā)電技術(shù)的效能及設(shè)備投資等因素,本文提出的基于有機(jī)朗肯循環(huán)的MVR熱泵精餾工藝尤其適合于塔頂塔底溫差不大且塔頂溫度大于 40℃的低腐蝕高能耗分離體系,且具有較好的工業(yè)應(yīng)用前景。
符 號(hào) 說(shuō) 明
AT——換熱器總換熱面積,m2
CA——換熱器造價(jià)系數(shù),850 CNY·m-2
CB——蒸氣單價(jià),220 CNY·t-1
CC——壓縮機(jī)造價(jià)系數(shù),820 CNY·kW-1
CE——美元對(duì)人民幣匯率,取6.5
CM——電價(jià),1.1 CNY·(kW·h)-1
CW——冷卻水單價(jià),0.35 CNY·t-1
COP——熱泵的循環(huán)性能系數(shù)
D——塔徑,m
GMORC——ORC系統(tǒng)發(fā)電量,kW
H——填料層高度,m
h1,h2,h3——分別為工質(zhì)在膨脹機(jī)進(jìn)口、出口、蒸發(fā)器入口的比焓值,kJ·kg-1
mwf——工質(zhì)質(zhì)量流量,kg·s-1
Δp——工質(zhì)在泵進(jìn)出口的壓強(qiáng)差,Pa
QB——塔底熱負(fù)荷,kW
QC——塔頂熱負(fù)荷,kW
Qout——熱泵系統(tǒng)輸出制熱量,kW
rB——水蒸氣冷凝潛熱,2177 kJ·kg-1
WC——壓縮機(jī)電耗,kW
Wexp——ORC系統(tǒng)凈輸出功,kW
Win——壓縮機(jī)輸入功率,kW
WP——泵的消耗功,kW
WT——膨脹機(jī)對(duì)外輸出功,kW
ηORC,ηP,ηS——分別為ORC系統(tǒng)熱效率、泵的效率和發(fā)電機(jī)效率,%
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date:2017-06-16.
GAO Xiaoxin,gxx@cczu.edu.cn
MVR heat pump distillation process of mixed xylene based on organic Rankine cycle
YANG Deming,GU Qiang,ZHU Biyun,WANG Zhengguang,YIN Yifan,GAO Xiaoxin
(College of Petrochemical Engineering,Changzhou University,Changzhou213164,Jiangsu,China)
Conventional mechanical steam compression(MVR) heat pump distillation for separating mixed xylene exists shortcomings of high compressor power consumption and overhead sensible heat unused.Organic Rankine cycle(ORC) power generation technology can transform the low-temperature waste heat into electricity for compressor,in view of the above,the MVR heat pump distillation processes coupled by the ORC power generation technology and combined with exhaust steam regenerative cycle(EGC) were applied to separate the system.Taking total annual cost(TAC) and energy consumption as the evaluation indexes of separation process,net output power and cycle thermal efficiency are used as evaluation indexes of ORC system.Simulations for the above two kinds of distillation process were performed and the results were compared with the conventional MVR heat pump distillation process.The results show that compared with the conventional MVR heat pump distillation process,the MVR heat pump distillation processes coupled by ORC power generation technology and combined with EGC power generation technology both have certain energy saving and economic advantages,can reduce energy consumption by 9.64% and 9.89%,and save TAC by 3.19% and 3.50% respectively.
mixed xylene system; MVR heat pump; organic Rankine cycle; distillation; computer simulation;energy consumption; total annul cost
TQ 028
A
0438—1157(2017)12—4641—08
10.11949/j.issn.0438-1157.20170781
2017-06-16收到初稿,2017-09-08收到修改稿。
聯(lián)系人:高曉新。
楊德明(1966—),男,教授。