HD đồ án môn học hấp thu

t : I I ' ,\ GIAO TRINH { lr\ "QUA TRII{H VA THIET BI AA, CONG NGHE HOA HOC'' I al T4,P 11 HuoNG nAr-r ob AN Mou Hoc cscchrcr ndP TFIU rAC GIA: V6 THI NGOC TIJdI PGS tt) rntJoNc DAr Hoc sicH KH0A Ub Crri WIINH - 1ee3 rHlgT Bl HAP rHu Qu:i trinh hdp thq xdy mQt cdu tt cria pha khf khu6'ch tdn vAo pha l6ng sg ti6p xdc gpna pha - l6ng, Thidt bi drrgc st? dgng dd ti6n hinh qu6 trinh hdp thq _dugc gqi ld thidt bi hdp ths'ho{c c,Qt hdp ths, th6p hdp thq Thidt b! hdp thrt c6 iftg ia viQc girin do4n ho{c lim viQc li€n tuc d day chring t6i chl gidi thi.0u hai kidu thidt bi lim viQc li6n tr;c: - thidt bi hdp thg loqi dQm - thidt b[ hdp thq lo4i mAm tinh to6n tld x6e dinh cric kich thtrdc co bAn chd y6u nhdt cria thdp hdp tirg, cr; thd la dtrdng kinh vir chibu cao thdp, phn hgp voi yOu chu sAn Chring ia cbr xudt vb ndng sudt vh hiQu sudt hdp thrl Ddi vdi thrip dQm, mu6n xric dinh chibu cao thrip thi ta cbn phii tinh.: 'sd don vi truybn khdi' - chibu cao mQt don vi truYbn khdi Ddi vd'i th6p mAm, ehibu cao thdp dtrgc xdc dinh theo e6c drr kiQn sau: sd mAm thr{c t0 cira th6P khoing c6ch girla e6c mArn Cdu trdc tron mAm c6 nhibtr kidu rdt da d4ng: mAm chdp, mAm ld c6 dng ch6y truybn vh kh6ng cd dng chdy truybn, mAm van v v , nhi6n e6ch xdc dinh sd mAm thrJc t6 &u gidng Chi khric viQc xdc tlinh khoAng uich gida cdc mAm C6 eing mQt kich thtldc drrdng kinh nhung khoing cdch c6c mAm eh6p ldn hon mAm 16 khong c6 dng ch6y truybn v v Trong bdt k' loqi thrip nio, pha vAn li pha liOn tuc vh chi c6 pha mdi tuAn theo ttinh ly liOn tuc vb tru.vbn vfn, d6 ta dtta vio pha ttd x6c dlnh kinh thdp Trinh tg tinh torin th6P hdP thq nhu drrdng sau: Ll- LUa chgn dung mOi hdP thq, ndu riung m0i dA dugc dinh trdd'c thi bd qua btrdc nhy 2l- XAy drlng dudng cAn blng vi dtrdng lirm viQc cua hQ hdp thg, tt d6 xric dinh lugng dung mOi cbn thiO't cho qria trinh 3/- Xic tllnh sd don vi truybn khdi vi chibu cao mQt dor vi truybn khdi ndu ta sr? dgng cQt dQm, ho{c xdc dinh sd mAm thr.fe td vDr kho6ng cdch mAm ndu ta st? dUng cQt mAm 4/- Tinh chibu cao thdp, iludng kinh thdp, c6c chi tidt tren mAm dd vi cd cdu tdm dQm 5/- Tfnh tr& lgc cria thaip dd tt tl6 tinh qu4t vfln chuydn khf vlo th6p Sau dAy ld phbn S I LI.'A CHON trinh biy kh6i qudt nOi dung tinh torin chn thidt DUNG MOI Trong tnrdng hgp dung mOi hdp thq khOng cho tnJdc thi ngudi thidt kd phii bidt c6ch lga chgn dung mdi mQt c6ch tdi uu, trlc lir phii th6a dring mdi hJcrng quan girla cdc vdn d0: Kinh td (16 tibn), hiQu sudt hdp thr.r vb dibu kiQn h{p thg Vi dg: Khi hdp thq ta c6 thd d&ng nrrdc, dung dich NaOH, KOH ho{c c6c dung dieh Otanolamin, v v M5i dung mOi dbu c5 nhrlng ddc didm ri6ng nhu sau: CO2 - U- Nrrdc: - R6 tibn, th6a mdn drroc dibu kipn kinh td - EQ hba tan CO2 rdt k6m d 6p sudt thudng, ndu mudn dat hi6u sudt hdp thg dring kd thi phii t6ng rip sudt hdp thg, nhrr vAy thidt bi s6 phfc tgp hon 2l- Dang dlch Naolt tro4c KOH - HiQu qua hdp thr; CO2 cao - Chi phi cho dung mOi cao hon nr/dc - Kh6ng thd hohn nguyOn dung mdi I Do d6 ngudi ta chi dtng dung mOi ndy tnrdng hgp &n phii rt?a sqch CO2 cho mQt h6n hgp hoflc vdi mgc dich tgo sin phdm vdi cdc 4rt g dich d6 3l- C6.c dung dlch Otanolamin, cg thd li: - mono6tanolamin (MEA): RNH2 - diOtanolamin (DEA): R2NH - tri€tanolamin (TEA): R3N d6 gde R c6 dqng -CHZ-CH2OH So srinh girla dung dich tr6n thi MEA c6 ndng hdp thq CO2 cao nhdt nhtrng cd nhrrgc didm: d6 bay hoi nOn hao tdn nhibu, tinh 6n mbn cao, ngoii cdn, ! Du kiQn: - Pha khi: nhi6t dQ, ning su5t, nbng dQ dEu, cu6i - Pha l6ng: dung m6i sti dqng, nbng dQ dBu, cu6i - Ap su{t hdp thg: P NhiQt d0 dung m6i ban dAu Tc Nhiqt dQ hdp Duilng cAn bing pha theo Tc (ch9n) vi blng (gii thigt) thqr: l5y P To Lugng dung m6i hgp ly L vh nbng d0 cudi pha l6ng X" NhiQt dg cudi pha l6ng T" t Du$ng cAn bdng NO T"-Ta:0 hi6u chinh yes (H{p thV df,ng nhiQt) Sfr dqng durong cAn bdng theo Ta kidu thap Thap mAm Thap dQm Chon cd d6m 56 mAm thuc td ChiEu cao d\rtk ChiEu cao Dudng kfnh thap thap, n6p, d6y Co c5u chi ti6t tr6n mAm Tfnh trd lgc th6p Bctm & Quqt & M6y n6n sd Db riwn nHAP HiP rW LIEN TVC" Du'dng kfnh thdp li0n kdt vdi rdt bbn CO2 nOn kh6 hoirn nguyOn dung m0i Do d6 ngudi ta hay chgn dung mOi DEA m{c dr) ning hdp thg c6 thdp hor MEA nhung vAn d4t ydu cbu vb hdp thg vi c6 thd hoiin nguyOn dung m0i Dung nta nang hdp thq cAng k6m hcrn nan khong thd chqn v v moi TEA "J T6m lgi, m6i dung moi ddu c6 tnr nhugc didm riOng, ta phii cAn nhdc cric mf;t dd lqa chon dung mOi thich hgP nhdt $ il- xAv lf {A DLTNG S0 1:rtt{AA\ LIEU CAN BANG VA SO LIEU VAN HANH Drrdng cAn bhng:pha Mudn x6c dlnh cdc th6ng sd vqn hbnh cho qwi trinh hdp thr,r, trudc ti6n ta ph6i biSt qic sd li6u eAn bing pha cria hQ khi-l6ng Ndu dung dich hdp thq kh6 lodng thi c6 thd xf cgng phuong trinh Henri dd bidu di6n dtrdng can bing: P= Hx (1.1) ho{c y== H -x P d6 p- dp sudt riCng phbn ctra cdu tfi hda tan cAn bhng pha H- hC sd Henri (don vi 6p sudt) P- rip sudt chung cia hQ y- nbng dQ cAn bhng ctia pha khi, lphhn mol] x- nbrig dg hda tan pha l6ng, [phhn mol] HQ sd Henri cd thd tra cdc sd tay ky sr/ h6a hgc H-e sd ndy ui !i:i tri khdc theo trlng hQ khf-l6ng vd phg thuQc nhibu vho nhiQt dQ r Ndu nhrr dung dich c6 nbng dQ hdp thg cao kh6ng thd sf dgng phrrcmg trinh Henri, thi ta phAi tim sd liQu cAn bing thgc nghiQm cdc sd tay ky sr'f h6a chdt Chn ehd f ld qu6 trinh hep thqr c6 thd xdy hiQn tuo.ng t6a nhi$t, mir sd liQu cAn bing phq thuQc nhibu vio nhiQt ilQ, d6 ta eln phii xAy dqmg tlldng cAn blng hiQu chinh theo nhi.6t dQ Tuy nhi6n, tnrdc ti0n ta phAi gii thiSt nhi$t tlQ hdp thq (cd thd giA thidt bhng nhiQt dQ dung mOi) tld tqo co s& ban dlu eho viQc xdc ilinh cric th0ng sd vfln hhnh dn thidt C6c th6ng sd vfn hAnh mA ngrrdi thidt kd c6 thd bidt tntdc tiOn li lrrgng pha cbn phAi n4p vho cQt hdp thg, nbng tlQ ban &u cria-pha khi, c6 cring bi6t nhiQt dQ pha nhflp liQu, nhtrng chtra dfi dd kiQn dd thi6't kd Ta chn phii c6 th6m cdc sd liOu vAn hhnh khdc nhtl sau: - Ifbrrg d0 cudi vi nhiQt d0 cudi cfia pha - Ltrgng dung m6i ebn thie't dd tud'i vio thdp, nbng d0 vA nhiet d0 dung rn6i & dinh vi d,iy thdp Ta s6 dga vio cdc phrrong trinh cAn bing vSt lipu vi cAn bing nhipt dd x6c cllnh cric s6 lipu niy Ddi vdi nbng a0 cria pha khi, c6 y6u cbu sin xudt "qdi cho trtldc mQt sd cg thd, ho4c c6 ngrrdi ta drta yOu clu dtrdi d4ng hiQu su{t hdp thqr phAi t14t clrrgc bao nhi€u phhn tr6m cdu tt? cbn trich 2/- Phuong Ky trinh c6n bhng vgt 1i9u hiQu: G- luqng khf tro, kh6ng ddi vf;n hinh, kmol/h L- lugng dung m0i, ' vi Xa, X"- nbng tlQ tlbu vi Yo, Y"- nbng ttQ dau X+- nbng dQ pha v{n hinh, kmol/h cudi cda pha khi, Kmol/I(mol tro khOng tldi cudi erSa pha l6ng, Kmol/I(mol dung mdi l6ng cAn bang tudng rtng vdi Y6, Kmolfi(mol dung m6i -J G,Y* Hinh Ndu nbng d0 1.7 : MO hinh cdn bdng ugt li€u ta gqi Gun le ltrgng h5n hgp n?p vho thdp hdp thq [Kmol/h] va ya le phhn mol cria h6n hgp ban dbu, thi ta s6 tinh Itrgng tro nhu sau: G-Gnrr(1 yd:Gnn 1+Yd Phrrong trinh cAn bbng vAt ligu GYa + td d6: LX'6- GY + LX" ci d4ng: (1-2) (1-3) - Y" G X.- Xd goc cta drrdng lhm Nhtr vfy, tf sd girla lrrgng dung moi L vi trd G la hc s6 L Yo = viQc Dd xAy dgng aoatrg lhm viQc c6 thd ca Y" vh X6 sudt hdp thq you cbu ld 95To, e6 nghia la cdn l4i 57o cdu tr? theo dbng kh6i thdp, rhtl vfy ta suy nbng dQ cu6i Y": Gii thu di ta phdi xdc dlnh c6c thong sd chr-ra bi6t: L' )Q' st? hiQu bi h6p Y" = 0'05 Ya Mudn x6c dinh t,rqrrg dung mdi ldm viQc thich hqp dung mOi tdi thidu L-io: L*io G Trong d6 x+ drrdng cAn bing L thi ta phii biSt lugng - Y" X*-Xu Ya (1-4) Cltrgc x6c dinh bing tlb thi, tudng rlng vdi giao didm c0a Ya vd'i - Dd x6c dinh Xa, ta ph6i d{t trrrdng hgp: -Ndudungm6isachkhivbothdpthiXd=O,dod6tac6: L*ir,-fu-Y" GX* Tt (1-5) d6 ta aO dhng xdc dinh L*i',' - Ndu ta xt? dgng dung m6i hobn nguyon thi ro ring x6 s6 c6 mQt giti tr! ndo d'Jqc 95Vo ch{t b! d6 trrong fng vdi diau kiQn vAn hhnh Vi dg: yeu cbu phii Lich 'c6: hdp thq.ra kh6i dung dleh thi ta s6 & _ & :0,g5 x" tfi d6 Xd - 0,05 X" Nphi ra, theo kinh 'l nghigm ngUdi t;a thay: L : (1,2 + 1,3) L*i* Tt cric phudng trinh tr0n, tB rdt -ra dUgc: ! =x*-xu L*ir, & )fu ho6c ndu Xa= thi: X* x" L*io ttT'c L4-rg ct 3l- CAn bhng nhig t n6ng: K)t hi€u: G"- lugng h6n hgp dbu vh cuOi, Ga, If's/h Lr- lugng dung dich dAu vi La, cudi, Ks/h td, tc- nhiet d0 "C ban &u vA cudi, * Ta, T"- nhigt d0 dung dich 1C &u vh cudi, fa, Ic- entalpi h6n hgp ban dbu cudi, KJ/kg Qo- vh Gst6Ts nhigt mdt m6t, KJ/h Phrrong trinh cAn beng GaIa + LdCdTd Lc Hinh Tc 1"2 nhiet c6 dang: + Q* - G"I" + L.C"T" + ( Qo 1-6) d5: Q.- nhipt ph6t sinh hdp thv khf, KJ/h od aon gi6n hda & tfnh todn, ta c6 thd gi6 thict nhrr sau: 'dn - nhipt mdt mdt moi tnrdng xung quanh kh0ng rling kd, tt6 lAy eo = - nhipt tlQ cria h6n hgp kh6i thrip bhng nhiQt d0 dung dich vio thrip: t": Td - tf nhiQt qria dung dich kh6ng ddi su6t qu6 trinh hdp thq ( tlQ ghn ttring cho ph6p, C6= Q"= ta ldy blng tf mt?c nhigt ctia ntrdc nou dung m6i ld nrldc), v6y: Q Trong qu6 trinh hdp thq c6 thd phrit sinh nhiQt, rt6 ndu ky hipu q ph6t sinh ctia mol edu tri bi hdp thu, thi ta s6 c6: Q":9L(&-xd li nhipt ( L-7) vdi mrlc tlQ ghn dring ta cd thd coi nhrr q kh6ng ,ldi qu6 trinh hdp thq Bay gid phuong trinh cAn blng nhi€t s6 cd dang: GaI6 ho6c: + LdCTd + qL(& - Xd = G"I" + L"CT" T" : tu ,u + - G"I" + qL (& L"C L"C GaIa L" (1-8) xd) lrrgng cdu tt? hba tan dung dich rdt nh6, d6 lugng dung dich dbu cudi L" kh0ng khdc nhibu, mt1c tlQ gpn thing ta e6 thd ldy: Vi L6 vi !1= r L" Dbng thdi ta cring c6 thd b6 qua mrlc tlQ bidn ddi nhiQt ctia pha khi, tfc li: GaIa-G"I"=g Nhrr vfy, cdng thfc tinh nhiQt dQ cudi T" cria dung dich sE c6 d4ng T" = Ta * 9L (& - Ndu ta ding dung m6i s4eh sau: xd (1-9) thi Xa= Td d6 ta thdy rd nhiQt dQ cr3a dung dieh tang dAn ttl tlinh ddn d6y th6p hdp thg vi nbng dQ cdu tt bi hdp thq tdng dAn Ndu nhrr ch€nh lQch nhiQt dQ girra T" vi T6 ldn thi ta phii v6 clrrdng cong cAn bing pha hiQu chinh x* T* Y 4ct