n mn hc Qu Trnh v Thit BGVHD: Tin Tin NamMC LCLI M U5CHNG I : TNG QUAN6I.Gii thiu v nguyn liu61.Methanol61.1.ng dng61.2.Sn xut62.Nc63.Hn hp Methanol nc7II.L thuyt v chng ct81.Khi nim82.Cc phng php chng ct91.2.Phn loi theo p sut lm vic92.2.Phn loi theo nguyn l lm vic93.2.Phn loi theo phng php cp nhit y thp93.Thit b chng ct9CHNG II: THUYT MINH QUY TRNH12I.Thuyt minh quy trnh cng ngh12II.Ch thch cc thit b trong qui trnh12CHNG III: TNH CN BNG VT CHT V NNG LNG14I.Cc thng s ban u14II.Cn bng vt cht141.Nng phn khi lng ca methanol trong thp142.Sut lng mol ca cc dng15III.Xc nh t s hon lu thch hp151.T s hon lu ti hiu152.Phng trnh ng lm vic s mm l thuyt16IV.S mm l thuyt17V.S mm thc t171.Xc nh hiu sut trung bnh ca thp:172.S mm thc t ca thp NTT:18VI.Cn bng nng lng19CHNG IV: TNH KCH THC THP V MM22I.NG KNH THP221.ng knh on ct222.ng knh on chng:24II.Chiu cao thp chng ct271.Chiu cao ca thp.272.Chiu cao y (np)27III.Mm l - tr lc ca mm281.Cu to mm l282.Tr lc ca a kh283.Tr lc do sc cng b mt294.Tr lc thu tnh do cht lng trn a to ra305.Tng tr thu lc ca thp326.Kim tra hot ng ca mm33CHNG V: TNH C KH33I.B dy thp331.Thn thp332.y v np35II.B dy mm361.Cc thng s cn tra v chn phc v cho qu trnh tnh ton362.Tnh b dy37III.Bch ghp thn y v np38IV.Chn thp381.Tnh trng lng ton thp392.Tnh chn thp39V.Tai treo thp40VI.Ca ni ng dn vi thit b - bch ni cc b phn ca thit b vi ng dn401.ng nhp liu402.ng hi nh thp413.ng hon lu424.ng hi y thp425.ng dn lng ra khi y thp43VII.Knh quan st44CHNG VI: TNH THIT B PH45I.Tnh chiu cao bn cao v:451.Tn tht ng ng dn:452.Tn tht ng ng dn trong thit b trao i nhit:463.Tn tht ng ng dn trong thit b gia nhit nhp liu:48II.Chn bm501.Tng tr lc trong ng ht v ng y:512.Kt lun52III.Thit b ngng t sn phm nh:531.Sut lng nc cn dng ngng t sn phm nh:532.Xc nh b mt truyn nhit :533.Xc nh h s cp nhit ca nc trong ng:544.Nhit ti qua thnh ng v lp cu:555.H s cp nhit ca hi ngng t:556.Kim tra sai s:56IV.Ni un gia nhit sn phm y:571.Sut lng hi nc cn dng :582.Xc nh b mt truyn nhit :583.Xc nh h s cp nhit ca hi nc:594.Nhit ti qua thnh ng v lp cu:595.Xc nh h s cp nhit ca sn phm y:606.Kim tra sai s:60V.Thit b lm ngui sn phm nh:611.Sut lng nc cn dng lm mt sn phm nh:622.Xc nh b mt truyn nhit :623.Kim tra sai s66VI.Thit b trao i nhit gia nhp liu v sn phm y:671.Nhit dng nhp liu sau khi trao i nhit vi sn phm y:672.Xc nh b mt truyn nhit :683.Kim tra sai s:72VII.Thit gia nhit nhp liu :731.Sut lng hi nc cn dng :732.Xc nh b mt truyn nhit :733.Kim tra sai s:77TI LIU THAM KHO78

LI M UMt trong nhng ngnh c s ng gp to ln n ngnh cng nghip nc ta ni ring v th gii ni chung, l ngnh cng nghip ha hc. c bit l ngnh ha cht c bn.Hin nay, trong nhiu ngnh sn sut ha hc cng nh s dng sn phm ha hc, nhu cu s dng nguyn liu hoc sn phm c tinh khit cao phi ph hp vi quy trnh sn sut hoc nhu cu s dng.Ngy nay, cc phng php c s dng nng cao tinh khit: trch ly, chng ct, c c, hp thu Ty theo c tnh yu cu ca sn phm m ta c s la chn phng php thch hp. i vi h Methanol - Nc l 2 cu t tan ln hon ton, ta phi dng phng php chng ct nng cao tinh khit cho Methanol n mn hc Qu trnh v Thit b l mt mn hc mang tnh tng hp trong qu trnh hc tp ca cc k s ho- th c phm tng lai. Mn hc gip sinh vin gii quyt nhim v tnh ton c th v: yu cu cng ngh, kt cu, gi thnh ca mt thit b trong sn xut ho cht - thc phm. y l bc u tin sinh vin vn dng nhng kin thc hc ca nhiu mn hc vo gii quyt nhng vn k thut thc t mt cch tng hp.Nhim v ca n Mn Hc (AMH) l thit k thp chng ct h Methanol - Nc hot ng lin tc vi nng sut nhp liu : 1500 kg/h c nng nhp liu l 20% mol methanol ,thu c sn phm nh c nng 94% mol methanolEm chn thnh cm n cc qu thy c b mn My & Thit B, cc bn sinh vin gip em hon thnh n ny. Tuy nhin, trong qu trnh hon thnh n khng th khng c sai st, em rt mong qu thy c gp , ch dn.

CHNG I : TNG QUANI. Gii thiu v nguyn liu1. MethanolMethanol cn gi l methyl alcohol,alcohol g,naphtha ghayru mnh g, c cng thc ho hc CH3OH(thng vit tt l MeOH). y l ru n gin nht, nh, d bay hi, khng mu, d chy cht lng vi mt mi c trng, rt ging, nhng hi ngt hn ethanol (ru thng). nhit phng, n l mt cht lng phn cc, v c s dng nh mt cht chng ng, dung mi, nhin liu, v nh l mt cht lm bin tnh cho ethanol Phn t lng: 32,04 g/mol Khi lng ring: 0,7918 g/cm3 Nhit nng chy: -970C (1760K) Nhit si: 64,50C (337,80K) nht: 0,59Ns/m2 200C1.1. ng dngMethanol c dung lm cht chng ng, lm dung mi, lm nhin liu cho ng c t trong, nhng ng dng ln nht l lm nguyn liu sn xut cc ho cht khc.Khong 40% methanol c chuyn thnh forml dehyde, t sn xut ra cht do, sn, Cc ho cht khc c sn xut t methanol bao gm dimeylete,1.2. Sn xutMethanol c sinh ra t s trao i cht ym kh ca 1 vi loi vi khun. Kt qu l 1 lng nh hi methanol c to thnh trong khng kh. V sau vi ngy khng kh c cha methanol s b oxy hoa bi O2 di tc dng ca nh sang chuyn thnh CO2 v H2O theo phng trnh2CH3OH + 3O2 2CO2 + 4H2OHin nay methanol c sn xut bng cch tng hp trc tip t H2 v CO, gia nhit p sut thp c mt cht xc tc.2. NcNcl mt hp cht ha hc caoxyvhidro, c cng thc ha hc lH2O. Vi cc tnh cht l ha c bit (v d nh tnhlng cc,lin kt hirv tnh bt thng ca khi lng ring) nc l mt cht rt quan trng trong nhiu ngnh khoa hc v trong i sng. 70% din tch caTri tc nc che ph nhng ch 0,3% tng lng nc trn Tri t nm trong cc ngun c th khai thc dng lm nc ung.Trong iu kin bnh thng: nc l cht lng khng mu, khng mi, khng v nhng khi nc dy s c mu xanh nht.Khi ho rn n c th tn ti dng 5 dng tinh th khc nhauTnh cht vt l: Khi lng phn t: 18 g/mol Khi lng ring d40C:1 g/mol Nhit nng chy:00C Nhit si:1000CNc l hp mt hp cht chim phn ln trn tri t (3/4 din tch tri t l nc bin) v rt cn thit cho s sng.3. Hn hp Methanol ncTa c bng cn bng lng hi cho hn hp methanol nc 1 atmBng 1T0C10092,387,781,77875,373,171,269,367,56664,5

x05102030405060708090100

y026,841,857,966,572,977,982,58791.595,8100

yX l thnh phn lngY l thnh phn hi

Biu th hin s thay i nhit , thnh phn lng, thnh phn hi ca hn hp methanol ncII. L thuyt v chng ct1. Khi nimChng ct l qu trnh dng tch cc cu t ca mt hn hp lng (cng nh hn hp kh lng) thnh cc cu t ring bit da vo bay hi khc nhau ca cc cu t trong hn hp (ngha l khi cng mt nhit , p sut hi bo ho ca cc cu t khc).Thay v a vo trong hn hp mt pha mi to nn s tip xc gia hai pha nh trong qu trnh hp th hoc nh kh, trong qu trnh chng ct pah mi c to nn bng s bc hi hoc ngng t.Trong trng hp n gin nht, chng ct v c c khng khac g nhau, tuy nhin gia hai qua trnh ny c mt ranh gii c bn l trong qu trnh chng ct dung mi v cht tan u bay hi (ngha l cc cu t u hin din trong c hai pha nhng vi t l khc nhau), cn trong qu trnh c c th ch c dung mi bay hi cn cht tan th khng bay hi.Khi chng ct ta thu c nhiu cu t v thng th h c bao nhiu cu t s thu c by nhiu sn phm. Nu xt h n gin ch c 2 cu t th ta thu c 2 sn phm:Sn phm nh ch yu gm cu t c bay hi ln v mt phn rt t cc cu t c bay hi bSn phm y ch yu gm cu t c bay hi b v mt phn rt t cu t c bay hi ln.Suy ra: vi quy trnh chng ct i vi h methanol nc thSn phm nh l methanolSn phm y l nc2. Cc phng php chng ct1.2. Phn loi theo p sut lm vic p sut thp p sut thng p sut cao2.2. Phn loi theo nguyn l lm vic Chng ct n gin Chng bng hi nc trc tip Chng ct a cu t3.2. Phn loi theo phng php cp nhit y thp Cp nhit trc tip Cp nhit gin tipVy i vi h methanol nc, ta nn chn phng php chng ct lien tc cp nhit gin tip.3. Thit b chng ctTrong sn xut thng dng nhiu loi thit b khc nhau tin hnh chng ct. Tuy nhin yu cu c bn chung ca cc thit b vn ging nhau l din tc b mt tip xc pha phi ln, diu ny ph thuc vo mc phn tn ca mt lu cht ny vo lu cht kia. Nu pha kh phn tn vo pha long3ta c cac loi thp mm, nu pha lng phn tn vo pha kh th ta c thp chem., thp phun, y ta kho st 2 loi thng dng l thp mm v thp chem.. Thp mm: thn thp hnh tr, thng ng pha trong c gn cc mm c cu to khc nhau, trn pha lng v pha hi c cho tip xc vi nhau. Tu theo cu to ca a, ta c: Thp mm chp: trn mm b tr c chp dng trn, xupap, ch S. Thp mm xuyn l: trn mm c nhiu l hay rnh Thp chm (thp m): thp hnh tr, gm nhiu bc ni tip nhau bng mt bch hay hn.Vt chm c cho vo thp theo mt trong hai phng php sau: xp ngu nhin hay xp th t.So snh u nhc im ca cc loi thp:Thp chmThp mm xuyn lThp mm chp

u im Cu to kh n gin Tr lc thp Lm vic c vi cht lng bn Tr lc tn i thp Hiu sut kh cao Kh n nh Hiu sut cao

Nhc im Do c hiu ng thnh nn hiu st truyn khi thp n nh thp, kh vn hnh Kh tng nng sut Thit b kh nng n Khng lm vic c vi cht lng bn Kt cu kh phc tp C tr lc ln Tiu tn nhiu vt t, kt cu phc tp

Quy trnh chng ct c thc hin da vo nhiu loi thp c cu to khc nhau, tuy nhin tu vo mc ch, hiu sut chng ct v iu kin khng gian cng nh iu kin kinh t m ta la chn thp chng ct ph hp. Qua qu trnh nghin cu, th ti thy thp mm xuyn l ph hp vi h methanol nc ny. Thp mm xuyn l c nhng u im sau: Ch to n gin V sinh d dng Tr lc thp hn thp chp t tn kim loi hn thp chpDo sn phm l methanol vi yu cu tinh khit cao khi s dng cng vi hn hp methanol nc l hn hp khng c im ng kh nn chn phng php chng ct lien tc l hiu qu nht.

CHNG II: THUYT MINH QUY TRNHI. Thuyt minh quy trnh cng nghHn hp methanol nc c nng nhp liu methanol 10% (theo phn hi lng), nhit khong 280C ti bnh cha nguyn liu (1) c bm (2) bm ln bn cao v (3). Sau hn hp c gia nhit thit b ngng t (8) ri chuyn vo un si n nhit si trong thit b gia nhit (6), hn hp c a vo thp chng ct (7) a nhp liu.Trong a nhp liu, cht lng c trn vi phn lng t on luyn ca thp chy xung. Trong thp, hi i t di ln gp cht lng i t trn xung. y, c s tip xc v trao i gia hai pha vi nhau. Pha lng chuyn ng trong phn chng ct cng xung di cng gim nng cc cu t d bay hi v b pha hi to nn t ni un (11) li cun cu t d bay hi. Nhit cng ln trn cng thp nn khi hi i qua cc a t di ln th cu t c nhit si cao l nc s ngng t li, cui cng trn nh thp ta thu c hn hp c cu t methanol chim nhiu nht (c nng 95% phn khi lng). Hi ny i vo thip b ngng t (8) v c ngng t hon ton. Mt phn cht lng ngng t c hon lu v thp a trn cng. Phn cn li c lm ngui n 400C, ri a v bnh cha sn phm nh.Mt phn cu t c nhit si thp c bc hi, cn li cu t c nhit si cao trong cht lng ngy cng tng. Cui cng, y thp ta thu c hn hp lng hu ht l cc cu t kh bay hi (nc). Hn hp lng y thp c nng methanol l 1,5% khi lng, cn li l nc. Dung dch lng y thp i vo thit b trao i nhit (11) vi dng nhp liu. Trong thit b trao i nhit dung dch lng mt phn s bc hi cung cp li cho thp lm vic lien tc, phn cn li ra khi thit b vo thit b lm ngui sn phm y (12). Sau , c a vo bn cha sn phm y (13).H thng lm vic lin tc cho ra sn phm nh l methanol. Sn phm y l nc sau khi trao i nhit vi dng nhp liu c thi b nhit 600C.II. Ch thch cc thit b trong qui trnh1. Bn cha nguyn liu2. Bm3. Bn cao v4. Van5. Lu lng k6. Thit b gia nhit dng nhp liu7. Thp chng ct8. Thit b ngng t9. Thit b lm ngui sn phm nh10. Bn cha sn phm nh11. Thit b gia nhit y thp12. Thit b lm ngui sn phm y13. Bn cha sn phm y14. By hi15. Phn phi lng16. p k17. Nhit k

CHNG III: TNH CN BNG VT CHT V NNG LNGI. Cc thng s ban uChn loi thp l thp mm xuyn l. Thit b hot ng lin tc.Khi chng luyn dung dch methanol th cu t d bay hi l methanolHn hp: Methanol: CH3OH, MR = 32 (g/mol) Nc: H2O, MN = 18 (g/mol) Nng sut nhp liu: GF = 1500 kg/h Nng nhp liu: phn mol matanol Nng sn phm nh: phn mol methanol Nng sn phm y: phn mol methanolChn Nhit nhp liu ban u: tB = 280C Nhit sn phm nh sau khi lm ngui: tPR = 300C Nhit dng nc lnh i vo: tV = 280C Nhit dng lnh i ra: tR = 400C Trang thi nhp liu vo thp chng ct l trng thi lng siCc k hiu: GF, F: sut lng nhp liu tnh theo kg/h, kmol/h GP, P: sut lng sn phm nh tnh theo kg/h, kmol/h GW, W: sut lng sn phm y tnh theo kg/h, kmol/h L: sut lng dng hon lu, kmol/h xi, : nng phn mol, phn khi lng ca cu t i.II. Cn bng vt cht1. Nng phn khi lng ca methanol trong thp% (theo khi lng)% (theo khi lng)% (theo khi lng)Khi lng phn t trung bnh dng nhp liu: kg/kmolKhi lng phn t trung bnh dng sn phm y, nh l: kg/kmol kg/kmolSuy ra: kmol/h2. Sut lng mol ca cc dngTa c:Cn bng vt cht cho ton thp: F = D + W(1)Cn bng cu t methanol(cu t nh) : F.xF = D.xD + W.xW(2)T (1) v (2) ta c: Suy ra: III. Xc nh t s hon lu thch hp1. T s hon lu ti hiuT s hon lu ti thiu l ch s m ch lm vic ti ng vi s mm l thuyt l v cc. Do , chi ph c nh l v cc nhng chi ph iu hnh (nguyn liu, nc, bm) l ti hiu.T bng s liu 1 ta xy dng th cn bng pha ca h methanol nc p sut 1 atm.

Xy dng th 2:

th 2: th cn bng pha ca h methanol nc p sut 1atmVi xF = 0,2 ta ni suy t t th 2 c yF* = 0,579 T s hon lu ti hiu tra cng thc IX.24 trang 158, [2] ta c:

T s hon lu lm vic: R = 1,3Rmin + 0,3 = 1,3 . 0.95 + 0,3 = 1,5352. Phng trnh ng lm vic s mm l thuyt Phng trnh ng lm vic ca on ct:

Phng trnh ng nng lm vic ca on chng:

Vi ch s nhp liu Phng trnh ng lm vic ca phn luyn:

IV. S mm l thuytT th ta thu c 10 mm bao gm: V. S mm thc tS mm thc t tnh theo hiu sut trung bnh:

Trong : : hiu sut trung bnh ca a, l mt hm s ca bay hi tng i v nht ca hn hp lng NTT : s mm thc t NLT : s mm l thuyt1. Xc nh hiu sut trung bnh ca thp: bay hi tng i ca cc cu t d bay hi: IX.61 trang 172, [2]Vi: x: phn mol ca ru trong pha lng. y*: phn mol ca ru trong pha hi.Ti v tr nhp liu:Ta c: xF = 0,2 ta tra th cn bng ca h: Suy ra: Mt khc: , tra bng trang 107, [1]

Suy ra: Tra bng trang 171, [2] ta c: 0,396Ti v tr mm y:Ta c: xW = 0,03 ta tra th cn bng ca h: Suy ra: Mt khc: , tra bng trang 107, [1]

Suy ra: Tra bng trang 171, [2] ta c: 0,42Ti v tr mm nh:Ta c: xD = 0,94 ta tra th cn bng ca h: Suy ra: Mt khc: , tra bng trang 107, [1]:

Suy ra: Tra bng trang 171, [2] ta c: 0,445Suy ra: hiu sut trung bnh ca thp l

2. S mm thc t ca thp NTT:

Vy ta c NTT = 21 mm, bao gmVI. Cn bng nng lngCn bng nhit lng cho ton thp chng ct:QF + Q = QW + QD + Qnt + Qm Nhit lng do hn hp ru nhp liu mang vo thp QF:QF = GF . HF = GF . CF.(tF to) , (KJ/h) IX.152 trang 197, [2]Trong : GF = = 31% nng khi lng nhp liu ban u CF : nhit dung ring ca hn hp ban u Chn nhit chun: t0 = 200C , tra bng I.154 trang 172, [1] ta c nhit dung ring ca ru: cR = 2719,1 (J/kg.).Suy ra: = 3731,3 (J/kg.)Vy QF = 1500 . 3731,3 . (81,7 20) = 0,35.109 (J/h) = 0,35.106 (KJ/h) Nhit lng sn phm y mang ra t ni un QWQW = GW . HW = W . MW.cW.(tw to) , (KJ/h) IX.160 trang 198, [2]Trong : W = 58,65 Kmol/h MW = 18,42 kg/kmol Chn nhit chun: to = 20oCDo sn phm y cha nhiu nc nn nhit dung ring ca sn phm y c th tnh gn ng theo cng thc sau:

Vy QW = 58,65 . 18,42 . 4060,42 . (95,38 20) = 0,331.109 (J/h) = 0,331.106 (KJ/h) Nhit lng sn phm nh mang ra t ni un QWQD = GD . HD = D . MD.cD.(tD to) , (KJ/h) trang 198, [2]Trong : D = 13,47 Kmol/h MD = 31,16 kg/kmol Chn nhit chun: to = 20oC , tra bng I.154 trang 172, [1], ta c nhit dung ring ca ru: cR = 2682,15 (J/kg.).Suy ra: = 2727,27 (J/kg.)Vy: QD = 13,47 . 31,16 . 2727,27 . (65,4 20) = 0,052.109 (J/h)= 0,052.106 (KJ/h) Nhit lng ngng t do hi sn phm nh ngng t thnh lngChn hi sn phm nh ngng t hon ton thnh lngQnt = D.(R+1).MD.rD (KJ/h) tD = 65,4 tra bng I.212 trang 254, [1] ta thu c Nhit ho hi ca nc: rN = 2401548,48 J/h = 2401,55 (KJ/h) Nhit ho hi ca ru: rR = 1096501,99 J/h = 1096,5 (KJ/h)Suy ra: = 1124,85 (KJ/h)Vy: Qnt = 13,47 . (1,535 + 1) . 31,16 . 1124,85 = 1,197.106 (KJ/h) Nhit lng tn tht ra mi trng xung quanh ly bng 5% nhit tiu tn Qm

Nhit lng cung cp cho ni un y thp Q:

= 1308510,638 (KJ/h) = 363,48 (KW) Nhit lng do hi t mang vo QD1 :QD1 = (QF + Qnt + Qm) - QfTrong QF = 0,35.106 (KJ/h) Qnt = 1,197.106 (KJ/h) Qm = (KJ/h) Qf = GF.Cf.tf (bng IX.151, trang 197, [2])Ta c: Tf = 28oC tra bng[30.104], trang 176, [2] ta c: Cf = 3972,5 J/kg.Suy ra: Qf = GF.cf.tf = 1500.3972,5.28 = 166,9.106 J/h = 0,1669.106 KJ/hVy: QD1 = (0,35.106 + 1,197.106 + ) - 0,1669.106 = 1,445.106 KJ/h

CHNG IV: TNH KCH THC THP V MMI. NG KNH THPTra cong thc IX.89,IX.90 trang 182 , [2] ta c cng thc sau: (m)Trong : Vtb : lng hi trung bnh i trong thp (m3/h) : tc hi trung bnh i trong thp (m/s) : lng hi trung bnh i trong tho (Kg/h)Lng hi trung bnh i trong on chng v on ct khc nhau. Do , ng knh on chng v on ct cng khc nhau1. ng knh on ct Lng hi trung bnh i trong thp: (kg/h) tra cng thc IX.91 trang 182, [2]Trong : gd : lng hi ra khi a trn cng ca thp (kg/h) gl : lng hi i vo a di cng ca on ct (kg/h)Xc nh gd : gd = D.(R+1).MD tra IX.92 trang 182, {2}= 13,47.(1,535 + 1).31,16 = 1064 (kg/h)Xc nh gl : tra ti liu IX.93,IX.94,IX.95 trang 182, [2] ta thu c h phng trnh sau:

Trong G1 : lng lng a th nht ca on ct r1 : n nhit ho hi ca hn hp i vo a th nht ca on ct rd : n nhit ho hi ca hn hp i ra nh thpTnh r1:Ta c t1 = tF = 81,7oC, tra ti liu tham kho bng I.212 trang 255, {1} ta c: Nhit ho hi ca nc l: rN1 = 41999,4 KJ/kmol Nhit ho hi ca ru l: rR1 = 33832,32 KJ/kmolSuy ra: r1 = rR1.y1 + (1-y1).rR1 = 41999,4 8167,08y1Tnh rdTa c tD = 65,40C, tra ti liu tham kho bng I.212 trang 255, {1} ta c: Nhit ho hi ca nc l: rNd = 43227,9 KJ/kmol Nhit ho hi ca ru l: rRd = 35088,1 KJ/kmolSuy ra: rd = rRd.yD + (1-yD).rRd = 35088,1.0,98 + (1-0,98).43227,9= 35250,9 KJ/kmolMt khc: x1 = xF = 0,2Gii h (*) trn ta c:_M1 = 25,14Vy: Tc trung bnh i trong thpTc gii hn ca hi i trong thp vi mm xuyn l c ng chy truyn:

Trong : Xc nh :

Vi: + Nng phn mol trung bnh: + Nhit trung bnh on ct: Suy ra: Xc nh :Nng phn mol trung bnh: Suy ra: Ta c: xtb = 0,57 suy ra ttb = 71,770C, tra bng I.2 trang 10, [1], ta thu c: Khi lng ring ca nc: Khi lng ring ca ru: Suy ra: Vy: trnh to bt ta chn tc hi trung bnh trong thp:

Vy ng knh on ct: 2. ng knh on chng: Lng hi trung bnh i trong thp: (kg/h) tra cng thc IX.91 trang 182, [2]Trong : gn : lng hi ra khi on chng (kg/h) : lng hi i vo on chng (kg/h)Xc nh gd : gn = g1 = Xc nh : tra ti liu IX.98,IX.99,IX.100 trang 183, {2} ta thu c h phng trnh sau:

Trong : lng lng a th nht ca on chng : n nhit ho hi ca hn hp i vo a th nht ca on chng Tnh :Ta c xW = 0,03 , tra th cn bng ca h ta c yW = 0,1608Suy ra Ta c = tW = 95,38oC, tra ti liu tham kho bng I.212 trang 255, {1} ta c: Nhit ho hi ca nc l: KJ/kmol Nhit ho hi ca ru l: = 32824,91 KJ/kmolSuy ra:

= 39659,01 KJ/kmol Tnh r1: r1 = 41999,4 8167,08y1 = 41999,4 8167,08 = 37834,19 (KJ/kmol)Gii h (**) trn ta c:_MtbG` = 19,05Vy: Tc trung bnh i trong thpTc gii hn ca hi i trong thp vi mm xuyn l c ng chy truyn:

Trong : Xc nh :

Vi: + Nng phn mol trung bnh: + Nhit trung bnh on chng: Suy ra: Xc nh :Nng phn mol trung bnh: Suy ra: Ta c: = 0,115 suy ra = 86,80C, tra bng I.2 trang 10, [1], ta thu c: Khi lng ring ca nc: Khi lng ring ca ru: Suy ra: Vy: trnh to bt ta chn tc hi trung bnh trong thp:

Vy ng knh on chng: Kt lun: hai ng knh on ct v chng khng chnh lch nhau qu ln nn ta chn ng knh ca ton thp l Dt = 0,6 (m).Khi tc lm vic thc : Phn ct: Phn chng: II. Chiu cao thp chng ct1. Chiu cao ca thp.Tra ti liu IX.54 trang 170, [2] ta c cng thc tnh chiu cao ton thp l:

Trong Hthp : chiu cao ca thp (m) Ntt : s mm thc t hmm : khong cch gia cc mm (m) : chiu dy ca mmTra bng IX.4a trang 170, [2] chn gi tr hmm = 0,41 (m), chn Suy ra 2. Chiu cao y (np) Chn y (np) tiu chun c:

Chn chiu cao g: Vy chiu cao y (np):

Kt lun: chiu cao ton thp l: H = Hthp + 2.Hy (np) = 9,67 + 2.0,175 = 10 (m)III. Mm l - tr lc ca mm1. Cu to mm lChn thp mm xuyn l c ng chy truyn: ng knh l: d1 = 3 (mm) = 0,003 (m) Tit din t do bng 8% din tch mm Chiu cao g chy trn : hg = 25 mm = 0,025 (m) Din tch ca 2 bn nguyt bng 20% din tch mm L b tr theo hnh lc gic u Khong cch gia 2 tm l bng 15 mm B dy mm bng 2 mm Mm c lm bng thp khng rS l trn 1 mm:

Gi a l s hnh lc gicTra cong thc V.139 trang 49, [2] ta c: n = 3a.(a 1) + 1 (***)Gii phng trnh (***) ta thu c: a = 115,969 116S l trn ng cho: b = 2a 1 = 231 l2. Tr lc ca a kh tra ti liu IX.140 trang 195, [2]Trong : : tc hi qua l (m/s) : khi lng ring trung bnh ca pha kh (hi) (kg/m3) : h s tr lc - (din tch l t 7% - 10% din tch thp)- (din tch l t 15% - 20% din tch thp)Phn ct:Vn tc hi qua l: Suy ra: Phn chngVn tc hi qua l: Suy ra: 3. Tr lc do sc cng b mtDo a c ng knh l ln hn 1mm nn ta p dng cng thc IX.142 trang 195, [2].

Phn ctTi nhit trung bnh ca pha lng trong phn luyn l T = 81,7oC tra ti liu I.242 v I.249 trang 301 v 311, [1] thu c: Sc cng b mt ca nc : Sc cng b mt ca ru : p dng cng thc I.76 trang 300, [1] ta c:

Suy ra: Phn chngTi nhit trung bnh ca pha lng trong phn luyn l T = tra ti liu I.242 v I.249 trang 301 v 311, [1] thu c: Sc cng b mt ca nc : Sc cng b mt ca ru : p dng cng thc I.76 trang 300, [1] ta c:

Suy ra: 4. Tr lc thu tnh do cht lng trn a to rap dng cng thc IX.143 trang 195, [2] :

Trong : hb : chiu cao ng chy chuyn nh ln trn a (m) : khi lng ring ca cht lng : gia tc trng trng ( 9,81 m/s2) : t s gia khi lng ring cht lng bt v khi lng ring cht lngTnh chiu cao ng chy truyn hc :Ta c : vi

Trong : Lg : chiu di ca g chy trn , m K = 0,5 : sut lng th tch ca pha lng, m3/sTnh chiu cao ca g chy trn:

Ta c :

Dng php lp: suy ra Nn Lg = Dt . = 0,6 . = 0,436 mPhn ct:Nng mol trung bnh ca phn ct: phn molKhi lng mol trung bnh ca phn ct: Sut lng th tch ca pha lng trong phn ct l:

Tra bng thu c cc thng s: GD = MD . D = 31,16 . 13,47 = 419,73 kg/h R = 1,535 Suy ra :

Kt lun:

Phn chng:Nng mol trung bnh ca phn ct: phn molKhi lng mol trung bnh ca phn ct: Sut lng th tch ca pha lng trong phn ct l:

Tra bng thu c cc thng s: GW = MW . D = 58,65 . 18,42 = 1080,3 kg/h R = 1,535 Suy ra:

Kt lun:

5. Tng tr thu lc ca thpPhn ct

Suy ra: Phn chng

Suy ra: 6. Kim tra hot ng ca mm Kim tra li khong cch mm hmm = 0,41 m m bo cho iu kin hot ng bnh thng ca thp (sch truyn khi, trang 70)Vi cc mm trong phn chng tr lc thu lc qu 1 mm ln hn tr lc thu lc ca mm trong phn ct:

Kt lun : iu kin trn c tho Kim tra tnh ng nht ca hot ng mm T cng thc trang 70 sch truyn khi, ta c vn tc ti thiu qua l ca pha hi Vmin cho cc l trn mm u hot ng:

Kt lun: Cc l trn mm hot ng bnh thng Kt lun : Tng tr lc thu lc ca thp

CHNG V: TNH C KHI. B dy thp1. Thn thp V than thp hot ng p sut thng nn ta thit k than hnh tr bng phng php hn h quang in, kiu hn gip ni 2 pha. Thn thp c ghp vi nhau bng cc mi ghp bch m bo cht lng ca sn phm ta chn thit b thn thp l thp khng g m X18H10 Cc thng s cn tra v chn phc v cho tnh ton: Nhit tnh ton: t = tmax = 1000C p sut tnh ton : V thp hot ng p sut thng nn:

Khi lng ring trung bnh ca pha lng trong ton thp:

Nn:

H s b sung do n mn ho hc ca mi trng: V mi trng c tnh n mn v thi gian s dng thit b l 20 nm Ca = 1 mm ng sut cho php tiu chun: V vt liu l X18H10T H s hiu chnh:V thit b khng bc lp cch nhit nn ng sut cho php: H s bn mi hnV s dng phng php hn h quang in, kiu hn gip ni 2 pha:Nn tra ti liu XIII.8 trang 364, [2] ta c Tnh b dy: ti liu XIII.8 trang 362, [2]Ta c: suy ra c th b p o mu p thao (1) trang 362, [2].Suy ra: Quy trn theo chun: S = 2 mm (Bng XIII.9 trang 366, [2])B dy ti thiu: Smin = 2 mmSuy ra: S = 2 mm Kim tra bniu kin: (tho iu kin)Nn: (tho)Kt lun: S = 2 mm2. y v np

Chn y v np c dn hnh elip tiu chun c g, lm bng thp X18H10T Chn b dy y v np bng vi b dy thn thp S = 2 mm Kim tra iu kin:Ta c: (tho)V y v np c hnh elip tiu chun vi hnh XIII.11 trang 383, [2]Suy ra: iu kin trn c tho nh kim tra phn thn thp Kch thc ca y v np ng knh trong : Dt = 600 mm Ht = 150 mm Chiu cao g: hg = 25 mm B dy: S = 2mm Din tch b mt trong: Sb mt trong = 0,44 m2 bng XIII.10 trang 384, [2]II. B dy mm1. Cc thng s cn tra v chn phc v cho qu trnh tnh ton Nhit tnh ton: t = tmax = 1000C p sut tnh ton: Chn b dy g chy trn l 3 mm Th tch ca g chy trn: Khi lng ring ca thp X18H10T l: Khi lng g chy trn: p sut do g chy trn tc dng ln mm trn: Khi lng ring ca cht lng ti y thp Ta c: xw = 0,03 suy ra tw = 95,380C bng I2 trang 10, [1] suy ra: Khi lng ring ca nc: Khi lng ring ca ru: p dng cng thc I.2 trang 6, [1] ta c:

p sut thu tnh: Suy ra: P = 333,48 + 8,98 = 342,45 H s b sung do n mn ho hc ca mi trng: V mi trng c tnh n mn v thi gian s dng thit b l 20 nm Ca = 1 mm ng sut cho php tiu chun: V vt liu l X18H10T H s hiu chnh:V thit b khng bc lp cch nhit nn ng sut cho php: Mdun n hi: H s Poisson: H s hiu chnh: 2. Tnh b dy ng sut cc i vng chu vi i vi bn trn c ngm kp cht theo chu vi: i vi bn c c l: Suy ra: Chn: S = 2 mm Kim tra iu kin bn: vng cc i tm: i vi bn c l c: Suy ra: m bo iu kin bn th:

Kt lun: b dy S chn tho bn

III. Bch ghp thn y v np

Chn bch c ghp thn, y v np lm bng thp CT3, cu to ca bch l bch lin khng c.Tra bng XIII.27 trang 419, [2] vi v p sut tnh ton P = 0,06.DtDDbDIDohBu lng

dBz

mmcimm

60074069065061120M2020

Tra bng IX.5 trang 171, [2] vi suy ra khong cch gia 2 mt bch l 1350 mm v s mm gia hai mt bch l 3 kn ca mi ghp bch ch yu do vt liu m quyt nh. Vy m bo kn cho thit b ta chn m l dy aming, c b dy l 3mmS mt bch cn dng ghp l bchIV. Chn thp

1. Tnh trng lng ton thpTra s tay XII.7 trang 315, [2] ta c khi lng ring ca thp CT3 l Khi lng ca mt bch ghp thn

Khi lng ca mt mm

Khi lng ca thn thp

Khi lng ca y (np) thp

Khi lng ca ton thp

2. Tnh chn thp Chn chn : thp c trn bn chn Vt liu lm chn thp l thp CT3 Ti trng cho php trn mt chn l: m bo an ton cho thit b ta chn GC = 2500 NTra bng XIII.35 trang 439, [2] ta thu c bng s liu sau:L BB1B2Hhsld

110809511018012064018

V. Tai treo thp

Chn tai treo: tai treo c gn trn thn thp gi cho thp khi b dao ng trong iu kin ngoi cnh Chn vt liu lm tai treo l thp CT3. Ta chn bn tai treo ti trng cho php trn 1 tai treo l: Gt = GC = 2500NTra bng XIII.36, trang 440, [2] ta thu c cc thng s sau:L BB1HSlad

9065751406351518

Khi lng mt tai treo l: mtay treo = 1 kgVI. Ca ni ng dn vi thit b - bch ni cc b phn ca thit b vi ng dn ng dn thng c ni vi thit b bng mi ghp tho c hoc khng tho c. Trong thit b ny, ta s dng mi ghp tho c. i vi mi ghp tho c, ngi ta lm on ng ni, l on ng ngn c mt bch hay ren ni vi ng dn Loi c mt bch thng dng vi ng c ng knh d > 10 mm Loi ren ch yu dng vi ng c ng knh , i khi c th dng vi ng dn c lm bng thp X18H10T Bch c lm bng thp CT3, cu to ca bch l bch lin khng c1. ng nhp liu Ta c: xF = 0,2 suy ra tw = 81,70C bng I2 trang 10, [1] suy ra: Khi lng ring ca nc: Khi lng ring ca ru: p dng cng thc I.2 trang 6, [1] ta c:

Chn loi ng ni cm su vo thit b Chn vn tc cht lng trong ng ni l vF = 1 m/s ng knh ca ng ni:

Suy ra chn ng c ng knh: Tra bng XIII.26 trang 419, [2] vi v p sut tnh ton P = 0,06 N/mm2DyDnDDIhBu lng

dBz

mmci

2532100756012M104

2. ng hi nh thp Nng trung bnh ca pha hi nh thp: Ta c xD = 0,94 suy ra tD = 65,40C v yD = 0,975 Khi lng mol trung bnh ca pha hi trong phn ct

Khi lng ring trung bnh ca pha hi trong phn ct l:

Chn vn tc hi ra khi nh thp l vHD = 40 m/s Dng knh trong ca ng ni

Suy ra chn ng knh ng ni l: Dy = 70 mm Tra bng XIII.32 trang 436, [2] suy ra chiu di on ng ni l: l = 110 mm Tra bng XIII.26, trang 419, [2] vi P = 0,06 N/mm2 ta thu c bng s liu sau:DyDnDDlhBu lng

dBz

mmci

707616013011016M124

3. ng hon lu Ta c: xD = 0,94 suy ra tw = 65,40C bng I2 trang 10, [1] suy ra: Khi lng ring ca nc: Khi lng ring ca ru: p dng cng thc I.2 trang 6, [1] ta c:

Chn loi ng ni cm su vo thit b Chn vn tc cht lng trong ng ni l vLD = 0,5 m/s ng knh trong ca ng ni

Suy ra chn ng knh ng ni l: Dy = 20 mmTra bng XIII.26, trang 419, [2] vi P = 0,06 N/mm2 ta thu c bng s liu sau:DyDnDDlhBu lng

dBz

mmci

2025105755818M124

4. ng hi y thp Nng trung bnh ca pha hi nh thp: Ta c xW = 0,03 suy ra tD = 95,380C v yD = 0,1608 Khi lng mol trung bnh ca pha hi trong phn ct

Khi lng ring trung bnh ca pha hi trong phn ct l:

Chn vn tc hi ra khi nh thp l vHW = 100 m/s Dng knh trong ca ng ni

Suy ra chn ng knh ng ni l: Dy = 100 mm Tra bng XIII.32 trang 436, [2] suy ra chiu di on ng ni l: l = 120 mm Tra bng XIII.26, trang 419, [2] vi P = 0,06 N/mm2 ta thu c bng s liu sau:DyDnDDlhBu lng

dBz

mmci

10010820517014818M164

5. ng dn lng ra khi y thp Ta c: xW = 0,03 suy ra tw = 95,380C bng I2 trang 10, [1] suy ra: Khi lng ring ca nc: Khi lng ring ca ru: p dng cng thc I.2 trang 6, [1] ta c:

Chn loi ng ni cm su vo thit b Chn vn tc cht lng trong ng ni l vLD = 0,5 m/s ng knh trong ca ng ni

Suy ra chn ng knh ng ni l: Dy = 32 mmTra bng XIII.26, trang 419, [2] vi P = 0,06 N/mm2 ta thu c bng s liu sau:DyDnDDlhBu lng

dBz

mmci

32381351007818M164

VII. Knh quan stChn ng knh trong ca knh quan st l Dtr = 100 mm ta c cc thng s sau: ng knh ngoi Dng = 180 m S bulng gp knh vi thp z = 16 ng knh bulng dB = M8 mm Khong cch gia hai bulng l h = 160 mm

CHNG VI: TNH THIT B PHI. Tnh chiu cao bn cao v:Chn ng knh ng dn nguyn liu (nhp liu): d = 25 (mm), nhm ca ng =0,1(mm).

Cc tnh cht l hc ca dng nhp liu c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbF == 54,85 oC: Khi lng ring: F = 985,7 (Kg/m3). nht ng lc: F = 0,508.10-3 (N.s/m2).Vn tc ca dng nhp liu trong ng dn:

vF == 0,96 (m/s).1. Tn tht ng ng dn:

(m).Vi: + 1 : h s ma st trong ng ng.+ l1 : chiu di ng ng dn, chn l1 = 20(m).+ d1 : ng knh ng dn, d1 = d = 0,025(m).+ 1 : tng h s tn tht cc b.+ vF : vn tc dng nhp liu trong ng dn, vF = 0,96(m/s).* Xc nh 1 :Chun s Reynolds ca dng nhp liu trong ng:

= 46568,5Ta ti liu II.60, II.62 trang 378, [1] v bng II.15 trang 381, [1] ta c:

Chun s Reynolds ti hn: Regh1===3301,1Chun s Reynolds khi bt u xut hin vng nhm:

Ren1===109674,38Suy ra: Regh1 < Re1< Ren1: khu vc chy qu , khi tra II.64 trang 380, [1] ta c :

1=* Xc nh 1:H s tn tht ca dng nhp liu qua: 10 ch un cong: u1=10.1,1 = 11. 3 van (van cu): v1= 3.1 = 3. 1 ln t thu: t1 = 0,5. 1 ln t m: m1 = 1. 1 lu lng k: l1 = 0 (khng ng k).Suy ra: 1 = u1 + v1 + t 1+ m1 + l1 = 15,5.

Vy:Tn tht ng ng dn: h1==1,86(m)2. Tn tht ng ng dn trong thit b trao i nhit:

(m).Vi: + 2 : h s ma st trong ng ng.+ l2 : chiu di ng ng dn, l2 = 40(m).+ d2 : ng knh ng dn, d2 = 0,021(m).+ 2 : tng h s tn tht cc b.+ v2 : vn tc dng nhp liu trong ng dn, v2 = 1(m/s).* Xc nh 2 :

Chun s Reynolds ca dng nhp liu trong ng: = 40747,4Ta ti liu II.60, II.62 trang 378, [1] v bng II.15 trang 381, [1] ta c:

Chun s Reynolds ti hn: Regh2===2704,68

Chun s Reynolds khi bt u xut hin vng nhm: Ren2===90140,4Suy ra: Regh2 < Re2< Ren2: khu vc chy qu , khi tra II.64 trang 380, [1] ta c :

2=* Xc nh 2:H s tn tht ca dng nhp liu qua: 9 ch ng cong quay ngc: q2=9.1,1 = 9,9 1 ch un cong: u2= 1,1. 1 ln co hp: c2 = 0,3. 1 ln m rng: m2 =.Suy ra: 2 = u2 + q2 + c2+ m 2 =11,387Vy:Tn tht ng ng dn trong thit b trao i nhit:

h2==3,6(m).3. Tn tht ng ng dn trong thit b gia nhit nhp liu:

(m).Vi: + 3 : h s ma st trong ng ng.+ l3 : chiu di ng ng dn, l3 = 15(m).+ d3 : ng knh ng dn, d3 = 0,021(m).+ 3 : tng h s tn tht cc b.+ v3 : vn tc dng nhp liu trong ng dn, v3 = 1,155(m/s).* Xc nh 3 :

Chun s Reynolds ca dng nhp liu trong ng: = 47063,3Ta ti liu II.60, II.62 trang 378, [1] v bng II.15 trang 381, [1] ta c:

Chun s Reynolds ti hn: Regh3===2704,68.

Chun s Reynolds khi bt u xut hin vng nhm:Ren3===90140,38.Suy ra: Regh3 < Re3 < Ren3: khu vc chy qu , khi (ti liu tham kho [4 (tp 1)]):

3=* Xc nh 3:H s tn tht ca dng nhp liu qua: 9 ch ng cong quay ngc: q3=9.1,1 = 9,9, 1 ch un cong: u3= 1,1. 1 ln co hp: c2 = 0,385. 1 ln m rng: m2 =.Suy ra: 3 = u3 + q3 + c3+ m 3 =12,0633.Vy:Tn tht ng ng dn trong thit b gia nhit:

h3==2,32(m).Chn : + Mt ct (1-1) l mt thong cht lng trong bn cao v.+ Mt ct (2-2) l mt ct ti v tr nhp liu thp.Ap dng phng trnh Bernolli cho (1-1) v (2-2):

z1 + + = z2 + + +hf1-2

hay z1 = z2 + +hf1-2Vi: + z1: cao mt thong (1-1) so vi mt t, hay xem nh l chiu cao bn cao v Hcv = z1.+ z2: cao mt thong (2-2) so vi mt t, hay xem nh l chiu cao t v tr nhp liu ti mt t:z2 = hchn + hnp + (Nchng+1) .(h + mm )= 0,12 + 0,15 + 7.(0,41 + 0,003) = 3,2 (m).+ P1 : p sut ti mt thong (1-1), chn P1 = 1 at.+ P2 : p sut ti mt thong (2-2).Xem P=P2 P1 =Nct . = 14 . = 4496,7 (N/m2). v1 : vn tc ti mt thong (1-1), xem v1 = 0(m/s). v1 : vn tc ti v tr nhp liu, v1 = vF = 0,96 (m/s). hf1-2 : tng tn tht trong ng t (1-1) n (2-2):hf1-2 = h1 + h2 + h3 = 1,86 + 3,6 + 2,32 = 7,78(m).

Vy: Chiu cao bn cao v: Hcv = z2 + +hf1-2

=3,2 ++ 7,78= 11,49(m).Chn Hcv = 12(m).II. Chn bmTa c: xf = 0,2 (phn mol) suy ra tF = 81,7 trang bng I.2 trang 10, [1] thu c: Khi lng ring ca nc: Khi lng ring ca ru: Suy ra:

Lu lng nhp liu: VF = (m3/h).Chn bm c nng sut l Qb = 1,5 (m3/h).ng knh ng ht, ng y bng nhau v bng 21(mm), ngha l chn ng 25x2.Cc tnh cht l hc ca dng nhp liu c tra bng I.249 trang 310, [1] ng vi nhit trung bnh Khi lng ring: F = 964,2 (Kg/m3). nht ng lc: F = 1,772.10-3 (N.s/m2).Vn tc dng nhp liu trong ng ht v y:

vht = vy = = 1,2(m/s).1. Tng tr lc trong ng ht v ng y:

hhd =Vi: + lh : chiu di ng ht, chn lh = 2 (m).+ ld : chiu di ng y, chn ld = 12 (m).+ h : tng tn tht cc b trong ng ht.+ d : tng tn tht cc b trong ng y.+ : h s ma st trong ng ht v ng y.* Xc nh :

Chun s Reynolds ca dng nhp liu: Re==13712,1Ta ti liu II.60, II.62 trang 378, [1] v bng II.15 trang 381, [1] ta c:

Chun s Reynolds ti hn: Regh===2704,68.

Chun s Reynolds khi bt u xut hin vng nhm: Ren===90140,38.Suy ra: Regh < Re < Ren: khu vc chy qu , tra II.64 trang 380, [1] ta c:

=* Xc nh h:H s tn tht cc b trong ng ht qua: 1 van cu: vh= 10. 1 ln vo ming thu nh: t = 5.Suy ra: h = vh + t =10,5.* Xc nh d:H s tn tht cc b trong ng y qua: 1 van cu: vd= 10. 2 ln un gc: u =2.1,1 = 2,2.Suy ra: h = vd + u =12,2.2. Kt lunVy:Tn tht trong ng ht v ng y:

hhd ==9,6(m).Chn : + Mt ct (1-1) l mt thng cht lng trong bn cha nguyn liu.+ Mt ct (2-2) l mt thng cht lng trong bn cao v.p dng phng trnh Bernolli cho (1-1) v (2-2):

z1 + + + Hb= z2 + + +hf1-2Vi: + z1: cao mt thng (1-1) so vi mt t.+ z2: cao mt thng (2-2) so vi mt t.+ P1 : p sut ti mt thng (1-1), chn P1 = 1 at.+ P2 : p sut ti mt thng (2-2), chn P2 = 1 at.+ v1,v2 : vn tc ti mt thng (1-1) v(2-2), xem v1=v2= 0(m/s).+ hf1-2 =hhd: tng tn tht trong ng t (1-1) n (2-2).+ Hb : ct p ca bm.Suy ra: Hb = (z2 z1) + hhd = Hcv + hhd = 10 +9,6 =19,6 (m cht lng)Chn hiu sut ca bm: b = 0,8.

Cng sut thc t ca bm: Nb == 96,6(W) = 0,13 (hp).Tm li: m bo thp hot ng lin tc ta chn bm li tm loi XM v Qb = 1,5 (m3/h) v ru l cht khng c hi.

III. Thit b ngng t sn phm nh: Chn thit b ngng t v ng loi TH t nm ngang. ng truyn nhit c lm bng thp X18H10T, kch thc ng: 25x2, chiu di ng l L = 1,5 (m). Chn nc lm lnh i trong ng vi nhit u: t1 = 28oC, nhit cui: t2 = 40oC. Cc tnh cht l hc ca nc lm lnh c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbN = =34oC: Nhit dung ring: cN = 4,181 (KJ/kg.). Khi lng ring: N = 994,4 (Kg/m3). nht ng lc: N = 0,7371.10-3 (N.s/m2). H s dn nhit: N = 0,6242 (W/moK).1. Sut lng nc cn dng ngng t sn phm nh:

GN == 6,627 (Kg/s).2. Xc nh b mt truyn nhit :B mt truyn nhit c xc nh theo phng trnh truyn nhit:

Ftb = ,(m2)Vi: + K : h s truyn nhit.+ tlog : nhit trung bnh logarit.* Xc nh tlog :Chn kiu truyn nhit ngc chiu, nn:

310C*Xc nh h s truyn nhit K: H s truyn nhit K c tnh theo cng thc:

,(W/m2.oK)Vi: + N : h s cp nhit ca nc trong ng (W/m2.oK).+ R : h s cp nhit ca hi ngng t (W/m2.oK).+ rt : nhit tr ca thnh ng v lp cu.3. Xc nh h s cp nhit ca nc trong ng:Chn vn tc nc i trong ng: vN = 0,75 (m/s).S ng trong mt ng nc:

(ng).

Chun s Reynolds : > 104 : ch chy ri, cng thc xc nh chun s Nusselt c dng: Trong : l : h s hiu chnh ph thuc vo ReN v t l chiu di ng vi ng knh ng:ReN=21247,86 v,nn l =1. PrN : chun s Prandlt ca nc 34oC, nn PrN = 5. Prw : chun s Prandlt ca nc nhit trung bnh ca vch.

Suy ra: H s cp nhit ca nc trong ng:

N = Nhit ti pha nc lm lnh:

(W/m2) (IV.4).Vi tw2 : nhit ca vch tip xc vi nc (trong ng).4. Nhit ti qua thnh ng v lp cu:

, (W/m2).Trong : tw1 : nhit ca vch tip xc vi ru (ngoi ng).

B dy thnh ng: t = 2 (mm).H s dn nhit ca thp khng g: t = 17,5 (W/moK).Nhit tr trung bnh ca lp bn trong ng vi nc sch: rc = 1/5000 (m2.oK/W).Suy ra: rt = 1/3181,818 (m2.oK/W).Vy: qt = 3181,818.(tw1-tw2) (IV.5)5. H s cp nhit ca hi ngng t:

t: A= vi [rR]=[J/kg].n nhit ngng t: rR = rD = 1124,85 (KJ/kg)Nhit ti ngoi thnh ng:qR = R.(65,4-tw1) = A.(65,4-tw1)0,75 (IV.6).T (IV.4), (IV.5), (IV.6) ta dng phng php lp xc nh tw1, tw2 :Chn: tw1 = 53,7oC :

Cc tnh cht l hc ca ru ngng t c tra bng I.2 trang 10, [1] ng vi nhit trung bnh ttbD = oC: Khi lng ring: R = 756,405 (Kg/m3). nht ng lc: R = 0,638.10-3 (N.s/m2). H s dn nhit: R = 0,2056 (W/moK).

Khi : A= T (IV.6): qR = 3145,44.(65,4-53,7)0,75 = 19898,54 (W/m2).Xem nhit ti mt mt l khng ng k: qt = qR =19898,54 (W/m2).

T (IV.5), ta c: tw2 = tw1- =47,450C

Suy ra: ttbw = =Ta c ttbw = 50,580C nn suy ra Prw = 7,43

T (IV.4): qN = (W/m2).6. Kim tra sai s:

= =1,21% < 5% : tho.Vy: tw1 = 53,7oC v tw2 = 47,45oC.

Khi : (W/m2.oC).

(W/m2.oC).

Ta c: (W/m2.oC).Nh vy: b mt truyn nhit trung bnh:

= 12,68 (m2).

Suy ra chiu di ng truyn nhit : L= (m).

So vi L = 1,5(m) th s ng nc l (ng nc).Khi s ng tng ln 5 ln: n=26.5 =130 (ng) ~ chn n = 140 (ng).Kim tra h s cp nhit ca ru khi c k n s nh hng ca s sp sp, b tr ng. Chn cch xp ng thng hng, b tr theo dng lc gic u,vy vi 140 ng th ta xp c 23 hnh lc gic u c cng tm

Khi : chiu di ng truyn nhit: L= = 1,25(m) < 1,5 (m) thoVy : Thit b ngng t sn phm nh l thit b truyn nhit v ng gm n=140(ng), di L=1,5(m).IV. Ni un gia nhit sn phm y: Chn ni un gia nhit sn phm y l ni un Kettle, ng truyn nhit c lm bng thp X18H10T, kch thc ng 25x2. Chn hi t l hi nc 2 at, i trong ng 25x2. Tra ti liu tham kho [4(tp1)], ta c: Nhit si: tsN = 119,6oC. An nhit ngng t: rN = 2208 (KJ/kg). Sn phm y trc khi vo ni un c nhit l tW = 95,38oC (do xw=0,03 phn mol ), nhit ra l t1 = 100oC.1. Sut lng hi nc cn dng :Lng nhit cn ti cung cp cho y thp: Q = 363,48 (KW).Sut lng hi nc cn dng:

GhN == 0,165 (Kg/s).2. Xc nh b mt truyn nhit :B mt truyn nhit c xc nh theo phng trnh truyn nhit:

Ftb = ,(m2)Vi: + K : h s truyn nhit.+ tlog : nhit trung bnh logarit.*Xc nh tlog :Chn kiu truyn nhit ngc chiu, nn:

(oK).*Xc nh h s truyn nhit K: H s truyn nhit K c tnh theo cng thc:

,(W/m2.oK)Vi: + N : h s cp nhit ca hi nc (W/m2.oK).+ D : h s cp nhit ca sn phm y (W/m2.oK).+ rt : nhit tr ca thnh ng v lp cu.3. Xc nh h s cp nhit ca hi nc:H s cp nhit ca hi nc c xc nh theo cng thc:

N =

=Vi: + tw1 : nhit ca vch tip xc vi hi nc(trong ng).+ A : h s ph thuc vo tnh cht vt l nc theo nhit , c tra ti liu tham kho [2].Nhit ti pha hi:

(W/m2) 4. Nhit ti qua thnh ng v lp cu:

, (W/m2).Trong : tw2 : nhit ca vch tip xc vi sn phm y (ngoi ng).

B dy thnh ng: t = 2 (mm). H s dn nhit ca thp khng g: t = 17,5 (W/moK). Nhit tr trung bnh ca lp bn trong ng vi nc sch: r1 = 1/5000 (m2.oK/W). Nhit tr lp cu pha sn phm y: r2 =1/500(m2.oK/W).Suy ra: rt = 1/1944,444 (m2.oK/W).Vy: qt = 1944,444.(tw1-tw2) 5. Xc nh h s cp nhit ca sn phm y:H s cp nhit ca sn phm y c xc nh theo cng thc (ch si si bt v xem sn phm y nh l nc):

D = .39.p0,5.(tw2 100)2,33Vi: p: p sut t nhit si ca sn phm y, khi p = 1 at = 105 (N/m2).Suy ra: D = 14343,143(tw2 100)2,33 Nhit ti pha sn phm y:

(W/m2)Chn: tw1 = 116,655oC :

Khi , nhit trung bnh = 118,128oC ta tra bng trang 120, [3] thu c: A = 187,1574Ta c: qN =73,415.187,1574.(119,6-116,655)0,75= 30889,133(W/m2).Xem nhit ti mt mt l khng ng k: qt = qN =30889,133 (W/m2).

Mt khc ta c: tw2 = tw1- =100,769oCSuy ra: qD =14343,143.(100,769-100)3,33=31708,196(W/m2).6. Kim tra sai s:

= =2,65% < 5% : tho.Vy: tw1 = 116,655oC v tw2 = 100,769oC.

Khi : (W/m2.oC).

(W/m2.oC).

Ta c: (W/m2.oC).

Nh vy b mt truyn nhit trung bnh l: = 10,77 (m2).Chn s ng truyn nhit: n = 140 (ng).

Chiu di ng truyn nhit: L (m).Chn: L = 1,2(m),(d tr khong 10%).Vy: ni un gia nhit sn phm y l thit b truyn nhit v - ng vi s ng n = 140, chiu di ng truyn nhit L = 1,2(m).ng c b tr theo hnh lc gic u. Nn ta c s ng trn ng cho hnh lc gic: b = 9(ng). Chn bc ngang gia hai ng: t = 1,4.dng = 1,4.0,025 = 0,035 (m).ng knh v thit b: Dv = t.(b-1)+4.dng = 0,035(9-1)+4.0,025 = 0,380(m).V. Thit b lm ngui sn phm nh:Chn thit b lm ngui sn phm nh l thit b truyn nhit ng lng ng. ng truyn nhit c lm bng thp X18H10T, kch thc ng trong: 16x1,6; kch thc ng ngoi: 25x2,5.Chn: Nc lm lnh i trong ng 16x1,6 (ng trong) vi nhit u: t1 = 28oC, nhit cui: t2 = 40oC. Sn phm nh i trong ng 25x2,5 (ng ngoi) vi nhit u:tD = 65,4oC, nhit cui: tD = 35oC.

Cc tnh cht l hc ca nc lm lnh c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbN = =34oC: Nhit dung ring: cN = 4,181 (KJ/kg.). Khi lng ring: N = 994,4 (Kg/m3). nht ng lc: N = 0,7371.10-3 (N.s/m2). H s dn nhit: N = 0,6242 (W/moK).

Cc tnh cht l hc ca nc lm lnh c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbD = oC: Nhit dung ring: cD= 2744,8 (J/kg.). Khi lng ring: D = 770,03 (Kg/m3). nht ng lc: D = 0,547.10-3 (N.s/m2). H s dn nhit: D = 0,211 (W/moK).1. Sut lng nc cn dng lm mt sn phm nh:Sut lng sn phm nh: GD = D.MD = 13,47.31,16 = 419,7 (Kg/h) = 0,12 (Kg/s).Lng nhit cn ti:QD = GD.cD.(tD-tD) = 0,12. 2744,8.(65,4 - 35) =10013,03(J/s) =10,01(KJ/s).Sut lng nc cn dng:

GN == 0,2 (Kg/s).2. Xc nh b mt truyn nhit :B mt truyn nhit c xc nh theo phng trnh truyn nhit:

Ftb = ,(m2)Vi: + K : h s truyn nhit.+ tlog : nhit trung bnh logarit.*Xc nh tlog :Chn kiu truyn nhit ngc chiu, nn:

(oK).*Xc nh h s truyn nhit K:H s truyn nhit K c tnh theo cng thc:

,(W/m2.oK)Vi: + N : h s cp nhit ca nc trong ng (W/m2.oK).+ D : h s cp nhit ca sn phm nh (W/m2.oK).+ rt : nhit tr ca thnh ng v lp cu.*Xc nh h s cp nhit ca sn phm nh ng ngoi:Vn tc ca sn phm nh i trong ng ngoi:

(m/s).ng knh tng ng: dtd = Dtr dng = 0,02- 0,016 = 0,004 (m).Chun s Reynolds tra II.58 trang 377, [1] ta c:

> 2320 : ch qu , cng thc xc nh chun s Nusselt c dng: Trong : l : h s hiu chnh ph thuc t l chiu di ng vi ng knh ng1, chn l =1. C : h s ph thuc vo chun s Reynolds, ReD = 3291,24 nn C = 17,096. PrD : chun s Prandlt ca sn phm nh 50,2oC, nn = 7,12. Prw1 : chun s Prandlt ca sn phm nh nhit trung bnh ca vch.

Suy ra: H s cp nhit ca sn phm nh trong ng ngoi:

D = Nhit ti pha sn phm nh:

(W/m2) Vi tw1 : nhit ca vch tip xc vi sn phm nh (ngoi ng nh). Nhit ti qua thnh ng v lp cu:

, (W/m2).Trong : tw2 : nhit ca vch tip xc vi nc (trong ng nh).

B dy thnh ng: t = 1,6 (mm). H s dn nhit ca thp khng g: t = 17,5 (W/moK). Nhit tr trung bnh ca lp bn trong ng vi nc sch: r1 = 1/5000 (m2.oK/W). Nhit tr lp cu pha sn phm nh: r2 = 1/5000 (m2.oK/W).Suy ra: rt = 1/2034,884 (m2.oK/W).Vy: qt = 2034,884.(tw1-tw2)*Xc nh h s cp nhit ca nc trong ng nh:Vn tc nc i trong ng:

(m/s).Chun s Reynolds :

> 104 : ch chy ri, cng thc xc nh chun s Nusselt c dng:

Trong : l : h s hiu chnh ph thuc vo ReN v t l chiu di ng vi ng knh ng:ReN=26938,24 ,chn l =1. PrN : chun s Prandlt ca nc 34oC, nn PrN = 5. Prw2 : chun s Prandlt ca nc nhit trung bnh ca vch.

Suy ra: H s cp nhit ca nc trong ng:

N = Nhit ti pha nc lm lnh:

(W/m2)Chn: tw1 = 42,65oC :Cc tnh cht l hc ca sn phm c tra bng I.249 trang 310, [1] ng vi nhit tw1=42,65oC: Nhit dung ring: cR= 2681,93 (J/kg.). nht ng lc: R = 0,425.10-3 (N.s/m2). H s dn nhit: R = 0,208 (W/moK).

Khi xem:Prw1 ~Suy ra:

qD = (W/m2).Xem nhit ti mt mt l khng ng k: qt = qD =16646,51 (W/m2).

Ta c: tw2 = tw1- =34,47oC

Suy ra: ttbw = =oCTra ti liu tham kho [1], Prw2 = 4,3Suy ra

qN = (W/m2).3. Kim tra sai sTa c:

= =0,82% < 5% : tho.Vy: tw1 = 42,65oC v tw2 = 34,47oC.

Khi : (W/m2.oC).

(W/m2.oC).Suy ra:

(W/m2.oC).Vy b mt truyn nhit trung bnh:

= 0,808 (m2).Suy ra chiu di ng truyn nhit :

L (m).Chn: L = 20(m),(d tr khong 15%).

Kim tra: th l = 1: tho.Vy: thit b lm mt sn phm nh l thit b truyn nhit ng lng ng vi chiu di ng truyn nhit L = 20(m), chia thnh 10 dy, mi dy di 2 (m).VI. Thit b trao i nhit gia nhp liu v sn phm y: Chn thit b thit b trao i nhit gia nhp liu v sn phm y l thit b truyn nhit ng lng ng. Ong truyn nhit c lm bng thp X18H10T, kch thc ng trong: 25x2 ; kch thc ng ngoi: 38x2. Dng nhp liu i trong ng 25x2 (ng trong) vi nhit u: tF = 28oC. Sn phm y i trong ng 38x2 (ng ngoi)vi nhit u: tW = 95,38oC, nhit cui: tW = 60oC.

Cc tnh cht l hc ca sn phm c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbW = =77,7oC: Nhit dung ring: cW = 4,094 (KJ/kg.). Khi lng ring: W = 958,1 (Kg/m3). nht ng lc: W = 0,363.10-3 (N.s/m2). H s dn nhit: W = 0,6 (W/moK).1. Nhit dng nhp liu sau khi trao i nhit vi sn phm y:Sut lng sn phm y: GW = W.MW = 58,65.18,42 = 1080,3 (Kg/h).Lng nhit cn ti:

Qt = .cW.(tW-tW) = .4,094.(95,38-60)=43,47(KW). 28oC, ta xem nhit dung ring ca sn phm nh l hng s, hay nhit dung ring ca ru cR = 2,595 (KJ/kg.).

Suy ra: cF = cR .+(1-).4,18 = 2,595.0,31+(1-0,31).4,18 = 3,69 (KJ/kg.).Nhit sn phm nh sau khi trao i nhit vi sn phm y:

tF = = 56,27oC.

Cc tnh cht l hc ca sn phm nh c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbF = oC: Khi lng ring: F = 910,91 (Kg/m3). nht ng lc: F = 0,55.10-3 (N.s/m2). H s dn nhit: F = 0,402 (W/moK).2. Xc nh b mt truyn nhit :B mt truyn nhit c xc nh theo phng trnh truyn nhit:

Ftb = ,(m2)Vi: + K : h s truyn nhit.+ tlog : nhit trung bnh logarit.*Xc nh tlog :Chn kiu truyn nhit ngc chiu, nn:

(oK).*Xc nh h s truyn nhit K: H s truyn nhit K c tnh theo cng thc:

,(W/m2.oK)Vi: + F : h s cp nhit ca dng nhp liu (W/m2.oK).+ W : h s cp nhit ca sn phm y (W/m2.oK).+ rt : nhit tr ca thnh ng v lp cu.*Xc nh h s cp nhit ca dng nhp liu ng trong:Vn tc dng nhp liu i trong ng:

(m/s).Chun s Reynolds :

> 104 : ch chy ri, cng thc xc nh chun s Nusselt c dng: Trong : l : h s hiu chnh ph thuc vo ReF v t l chiu di ng vi ng knh ng: ReF=45909,9 ,chn l =1. PrF : chun s Prandlt ca dng nhp liu 42,2oC, nn PrF = = 4,87. Prw2 : chun s Prandlt ca dng nhp liu nhit trung bnh ca vch.

Suy ra: H s cp nhit ca dng nhp liu trong ng:

N = Nhit ti pha dng nhp liu:

(W/m2)Vi: tw2 : nhit ca vch tip xc vi dng nhp liu (trong ng nh).*Nhit ti qua thnh ng v lp cu:

, (W/m2).Trong : tw1 : nhit ca vch tip xc vi sn phm y (trong ng nh).

B dy thnh ng: t = 2(mm). H s dn nhit ca thp khng g: t = 17,5 (W/moK). Nhit tr trung bnh ca lp bn trong ng vi nc sch: r1 = 1/5000 (m2.oK/W). Nhit tr lp cu pha sn phm nh: r2 = 1/5000 (m2.oK/W).Suy ra: rt = 1/1944,444 (m2.oK/W).Vy: qt = 1944,444.(tw1-tw2)*Xc nh h s cp nhit ca sn phm y ngoi ng nh:Vn tc nc i trong ng ngoi:

= 0,75(m/s).ng knh tng ng: dtd = Dtr dng = 0,034- 0,025 = 0,009 (m).Chun s Reynolds :

> 104 : ch chy ri, cng thc xc nh chun s Nusselt c dng: Trong : l : h s hiu chnh ph thuc vo ReW v t l chiu di ng vi ng knh ng:ReW=17815,9 ,chn l =1. PrW : chun s Prandlt ca sn phm y 80oC, xem sn phm gn nh l nc nn PrW = 2,21.

Suy ra: H s cp nhit ca sn phm y trong ng ngoi:

W = Nhit ti pha sn phm y:

(W/m2)Chn: tw1 = 72,1oC :Khi xem:Prw1 ~ 2,487 (tra tw1).

Ta c: qW = (W/m2).Xem nhit ti mt mt l khng ng k: qt = qW =26928,5 (W/m2).

Ta c: tw2 = tw1- =58,25oC

Suy ra: ttbw = =oCCc tnh cht l hc ca dng nhp liu c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbw = 65,2 oC: Nhit dung ring: cR = 3,62 (KJ/kg.). nht ng lc: R = 0,407.10-3 (N.s/m2). H s dn nhit: R = 0,39 (W/moK).

Khi : Prw2 == 3,8

Ta c : qF = = 44912,1(W/m2).3. Kim tra sai s:

= =0,66% < 5%: tho.Vy: tw1 = 72,1oC v tw2 = 55,087oC.

Khi : (W/m2.oC).

(W/m2.oC).

Suy ra: (W/m2.oC).

Nh vy b mt truyn nhit trung bnh l: = 1,24 (m2).

Suy ra chiu di ng truyn nhit : L (m).Chn: L = 21(m),(d tr khong 20%).

Kim tra: th l = 1: tho.Vy: thit b trao i nhit gia dng nhp liu l thit b truyn nhit ng lng ng vi chiu di ng truyn nhit L = 18(m), chia thnh 9 dy, mi dy di 2 (m).VII. Thit gia nhit nhp liu :Chn thit b gia nhit nhp liu l thit b truyn nhit ng lng ng. Ong truyn nhit c lm bng thp X18H10T, kch thc ng trong:25x2; kch thc ng ngoi: 38x2.Dng nhp liu i trong ng 25x2 (ng trong) vi nhit u: tF =56,27oC ,nhit cui: tF =81,7oC.Chn hi t l hi nc 1 at, i trong ng 38x2(ng ngoi). Tra ti liu tham kho [1]ta c: Nhit si: tsN = 100oC. An nhit ngng t: rN = 2260 (KJ/kg).

Cc tnh cht l hc ca dng nhp liu c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbF = =69oC: Nhit dung ring: cF = 3,634 (KJ/kg.). Khi lng ring: F = 917,59 (Kg/m3). nht ng lc: F = 0,37.10-3 (N.s/m2). H s dn nhit: F = 0,39 (W/moK).1. Sut lng hi nc cn dng :Lng nhit cn ti cung cp cho dng nhp liu:

Qc = .cF.(tF tF) =.3,634.(81,7 - 56,27)=38,5 (KW).Sut lng hi nc cn dng:

GhN == 0,017 (Kg/s).2. Xc nh b mt truyn nhit :B mt truyn nhit c xc nh theo phng trnh truyn nhit:

Ftb = ,(m2) Vi: + K : h s truyn nhit.+ tlog : nhit trung bnh logarit.*Xc nh tlog :Chn kiu truyn nhit ngc chiu, nn:

(oK).*Xc nh h s truyn nhit K: H s truyn nhit K c tnh theo cng thc:

,(W/m2.oK) Vi: + F : h s cp nhit ca dng nhp liu (W/m2.oK).+ N : h s cp nhit ca hi nc (W/m2.oK).+ rt : nhit tr ca thnh ng v lp cu.* Xc nh h s cp nhit ca dng nhp liu trong ng nh:Vn tc dng nhp liu i trong ng ngoi:

= 1,3 (m/s).

Chun s Reynolds : > 104 : ch chy ri, cng thc xc nh chun s Nusselt c dng: Trong : l : h s hiu chnh ph thuc vo ReW v t l chiu di ng vi ng knh ng:ReW=29015,7 ,chn l =1. PrF : chun s Prandlt ca dng nhp liu 69oC, nn PrF == 3,44

Suy ra: H s cp nhit ca dng nhp liu trong ng nh:

F = Nhit ti pha dng nhp liu:

(W/m2) (IV.24).Vi tw2 : nhit ca vch tip xc vi dng nhp liu (trong ng nh).* Nhit ti qua thnh ng v lp cu:

, (W/m2).Trong : tw1 : nhit ca vch tip xc vi hi nc (ngoi ng nh).

B dy thnh ng: t = 2(mm). H s dn nhit ca thp khng g: t = 17,5 (W/moK). Nhit tr trung bnh ca lp bn trong ng vi nc sch: r1 = 1/5000 (m2.oK/W). Nhit tr lp cu pha sn phm nh: r2 = 1/5000 (m2.oK/W).Suy ra: rt = 1/1944,444 (m2.oK/W).Vy: qt = 1944,444.(tw1-tw2) * Xc nh h s cp nhit ca hi nc trong ng nh:ng knh tng ng: dtd = Dtr dng = 0,034- 0,025 = 0,009 (m)H s cp nhit ca hi nc c xc nh theo cng thc:

N=

=Nhit ti pha hi nc:

(W/m2) (IV.26).Chn: tw1 = 97,44oC :

Khi , nhit trung bnh = 98,72oC ta tra c A = 178,36Ta c: qN =91,265.178,36.(100 96,92)0,75= 32944,407(W/m2).Xem nhit ti mt mt l khng ng k: qt = qW =32944,407 (W/m2).

Mc khc ta c: tw2 = tw1- =80,497oC

Suy ra: ttbw = =oCCc tnh cht l hc ca dng nhp liu c tra bng I.249 trang 310, [1] ng vi nhit trung bnh ttbw = 89 oC: Nhit dung ring: cR = 3,69 (KJ/kg.). nht ng lc: R = 0,288.10-3 (N.s/m2). H s dn nhit: R = 0,389 (W/moK).

Khi : Prw2 == 2,7

Suy ra: qF = (W/m2).3. Kim tra sai s:

= =1,13% < 5%: tho.Vy: tw1 = 97,44oC v tw2 = 80,497oC.

Khi : (W/m2.oC).

(W/m2.oC).

Ta c: (W/m2.oC).

Suy ra b mt truyn nhit trung bnh l: = 0,9966 (m2).

Suy ra chiu di ng truyn nhit : L (m).Chn: L = 17(m),(d tr khong 20%).

Kim tra: th l = 1: tho.Vy: thit b gia nhit dng nhp liu l thit b truyn nhit ng lng ng vi chiu di ng truyn nhit L = 15(m), chia thnh 10 dy, mi dy di 1,5 (m).

TI LIU THAM KHO[1] . S tay qu trnh v thit b cng ngh ho cht (tp 1) Nh xut bn khoa hc v k thut.[2] . S tay qu trnh v thit b cng ngh ho cht (tp 2) Nh xut bn khoa hc v k thut.[3] . H L Vin Thit k v tnh ton cc chi tit thit b ho cht Nh xut bn khoa hc v k thut H Ni 1978.[4] . Phm Vn Bn, Nguyn nh Th - Qu trnh v thit b cng ngh ho hc, Qu trnh v thit b truyn nhit(tp 5) Nh xut bn i Hc Quc Gia TP.HCM. [5] . Phm Vn Bn, V B Minh, Hong Minh Nam Qu trnh v thit b cng ngh ho hc, V d v bi tp(tp 10) - Trng i Hc Bch Khoa TP.HCM [6] .Tp th ging vin B Mn C Lu Cht Gio Trnh C Lu Cht Trng i Hc Bch Khoa TP.HCM.[7] . V Vn Ban, V B Minh Qu trnh v thit b cng ngh ho hc, truyn khi(tp 3) Trng i Hc Bch Khoa TP.HCM.

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