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MC LC mc Trang

LI TA ........................................................... Error! Bookmark not defined. Mc Lc ............................................................................................................ 1 GII THIU V M UN ................................................................................. 3 Bi 10. NHNG KIN THC C BN CA THY LC HC ....................... 5 A. TNH LC HC CHT LNG ..................................................................... 5 10.1. NHNG TNH CHT VT L CA CHT LNG .................................... 5 10.2. PHNG TRNH C BN CA TNH LC HC CHT LNG ........... 8 B. NG LC HC CA CHT LNG ........................................................ 13 10.3. NHNG KHI NIM .............................................................................. 13 10.4. PHNG TRNH DNG LIN TC ..................................................... 18 10.5. PHNG TRNH BERNULLI................................................................ 19 10.7. TR LC TRONG NG DN CHT LNG ........................................ 23 10.8. CU HI V BI TP ........................................................................... 25 10.9. THC HNH ......................................................................................... 31 Bi 11. VN CHUYN CHT LNG .............................................................. 32 11.1. CC THNG S C TRNG CA BM .......................................... 32 11.2. BM TH TCH ..................................................................................... 36 11.3. BM LY TM ........................................................................................ 43 11.4. CC LOI BM KHC ......................................................................... 51 11.5. SO SNH V CHN BM .................................................................... 52 11.6. CU HI V BI TP ........................................................................... 53 11.7. THC HNH ......................................................................................... 57 Bi 12. VN CHUYN V KH NN .............................................................. 60 12.1. MY NN PITTNG ............................................................................ 62 12.2. MY NN V THI KH KIU RTO ................................................... 68 12.3. QUT ..................................................................................................... 70 Bi 13. PHN RING BNG PHNG PHP LNG ................................... 72 13.1. LNG TRONG TRNG TRNG LC ............................................... 72 13.2. THIT B LNG ..................................................................................... 76

13.3. LNG TRONG TRNG LC LY TM ............................................... 80 13.4. CU HI V BI TP ........................................................................... 87 Bi 14. PHN RING BNG PHNG PHP LC ..................................... 95 14.1. PHNG TRNH LC .......................................................................... 96 14.2. THIT B LC ........................................................................................ 98 14.3. CU HI V BI TP ......................................................................... 100 14.4. THC HNH ....................................................................................... 103 Bi 15. KHUY TRN CHT LNG ............................................................ 105 15.1. KHUY TRN BNG C KH ............................................................ 105 15.2. CU TO CNH KHUY .................................................................... 108 15.3. KHUY BNG KH NN...................................................................... 111 15.4. CU HI .............................................................................................. 113 15.5. THC HNH ....................................................................................... 113 Bi 16. P NGHIN SNG VT RN ................................................. 114 16.1. P NGHIN ...................................................................................... 114 16.2. PHN LOI VT LIU......................................................................... 129 16.3. THC HNH ....................................................................................... 136 16.4. CU HI TRC NGHIM.................................................................... 137 THUT NG CHUYN MN ....................................................................... 140 TI LIU THAM KHO ................................................................................. 141

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GII THIU V M UNV tr, ngha, vai tr m un Trang b cho sinh vin v cc c s cc qu trnh v thit b thy lc nh bm, qut, my nn, phn ring h khng ng nht. Ngoi ra cn cp n kin thc v c hc vt liu ri nh p, nghin sng v vn chuyn vt liu ri trong ngnh cng ngh ho hc v thc phm Mc tiu ca m un Hc xong mun ny, hc sinh cn phi: Gii thch c tt c cc qu trnh v cc thit b trong cng ngh ha hc, nht l cc thit b trong ha du. Vn hnh c cc thit b thng dng. Tnh ton cn bng vt cht, cn bng nhit lng cc qu trnh. Tnh ton cc thng s c bn ca thit b.trong chng trnh dy ngh.

Mc tiu thc hin ca m un Khi hon thnh mun ny, hc sinh c kh nng: M t l thuyt v qu trnh thu lc, c hc. Nguyn l hot ng ca cc thit b. Tnh ton cn bng vt cht (CBVC), cn bng nhit lng (CBNL) trong mt s thit b phn ng Tnh ton kch thc thit b S dng cc thit b trong phng th nghim (PTN), c bit l thit b ha du. Thc hin cc th nghim trong PTN. Vai tr ca cc qu trnh trong cng ngh ha hc Cc qu trnh thu lc. Cc qu trnh nhit. Tnh ton CBVC, CBNL. Tnh kch thc thit b. Mun gm 7 bi: BI 10. Nhng kin thc c bn ca thy lc hc3

Ni dung chnh/cc bi ca m un

BI 11. Vn chuyn cht lng BI 12. Vn chuyn cht kh BI 13. Phn ring h kh khng ng nht BI 14. Phn ring h lng khng ng nht BI 15. Khuy trn BI 16. p-nghin-sng vt liu rn

4

Bi 10 NHNG KIN THC C BN V THY LC HC M s: QTTB10

Gii thiu Trong cc qu trnh sn xut ha hc, vt liu c ch bin dng lng hoc hi (kh). Cc qu trnh vn chuyn, qu trnh khuy trn, lng, lc, ly tm u lin quan n chuyn ng dng v tun theo cc nh lut thy lc hc. Mc tiu thc hin Hc xong bi ny hc sinh c kh nng: M t phng trnh c bn tnh lc hc. Vit c phng trnh cn bng thy tnh. Vit c phng trnh chuyn ng ca cht lng. Tnh c tr lc trong ng dn.

A. TNH LC HC CHT LNG Nghin cu cc nh lut cn bng ca cht lng v tc ng ca n ln cc vt th rn trng thi ng yn khi tip xc vi n. Khi nghin cu cc qu trnh thy lc, ngi ta dng khi nim cht lng l tng l cht lng hon ton khng chu nn p, khng c lc ma st ni gia cc phn t cht lng. 10.1. NHNG TNH CHT VT L CA CHT LNG 10.1.1. Khi lng ring L khi lng ca 1 n v th tch lu cht

limv

0

m , kg/m3 V

(10.1)

Trong : -khi lng ring lu cht, kg/m3 (h SI) m khi lng lu cht trong th tch V 10.1.2. Th tch ring L th tch ca lu cht trong mt n v khi lng. v=1/ , m3/kg (10.2)

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10.1.3. Trng lng ring L trng lng ca mt n v th tch

P VTrong :

mg V

.g , N/m3

(10.3)

P Trng lng ca lu cht, N V Th tch lu cht, m3 g- Gia tc trng trng, m/s2 m-Khi lng ca lu cht. 10.1.4. T trng L t s gia trng lng ring cht lng so vi trng lng ring ca nc. Trng lng ring k hiu d.

d

chat long

chatlong g nc g

chatlong nc(10.4)

nc

10.1.5. Khi lng ring kh l tng L khi lng ca mt n v th tch khi kh. Phng trnh trng thi pV=nRT hay Trong : p p sut khi khng kh tc ng ln thnh bnh,at R-hng s, ph thuc vo cht kh (R=0.082 l.at/mol.) V-Th tch khi kh, l 10.1.6. Cc loi p sut p sut l i lng vt l biu th lc tc dng ln mt n v din tch. Nu lc tc dng c phn b u trn din tch b mt th p sut c tnh theo cng thc:

m V

pM , kg/m3 RT

(10.5)

pTrong :

S F

, N/m2

(10.6)

S lc tc dng, N; F din tch b mt chu lc, m26

Trong k thut ngi ta thng phn bit cc loi p sut sau: p sut kh quyn: bng 0 nu tnh theo p sut d hoc p sut chn khng, bng 1at nu tnh theo p sut tuyt i. p sut d: l p sut so vi p sut p sut kh quyn v c tr s ln hn p sut kh quyn p sut chn khng: l p sut so vi p sut kh quyn v c tr s nh hn p sut kh quyn. p sut tuyt i: l p lc ton phn tc ng ln b mt chu lc. p sut tuyt i lun c gi tr bng 0 Quan h gia cc loi p sut c biu din nh hnh 1.1. Cn lu rng, p sut chn khng v p sut d so vi p sut kh quyn v lc ny p sut kh quyn qui c bng 0

Pd Pkq = 0 (theo ap suat d) Pck Pt Pkq = 1 (theo ap suat tuyet oi) Pt Pkq = 1 (theo ap suat tuyet oi) Pkq = 0 (theo ap chan khong)

Pt = 0 Bieu dien ap suat d

Pt = 0 Bieu dien ap suat chan khong

Hnh 10.1: Quan h gia cc loi p sut n v ca p sut theo h SI l N/m2. Ngoi ra cn c mt s loi p sut khc: mmHg, mH2O,at, kG/cm2, Pa, bar, Psi. Quan h gia cc n v ny nh sau: 1atm (tmospher vt l)=760 mmHg=10,33 mH2O=1,033 kG/cm2 1at (tmospher k thut) =735,5mmHg =10mH2O =10kG/cm2 =14,22Psi 1bar=9,81.104 N/m2 =9,81.104Pa V d: p k bn trong mt thit b ch p sut l 12at. Tnh p sut tuyt i7

theo n v (at), (N/m2). Gii p k ch p sut d vy p sut tuyt i bn trong thit b l: p=pa + pd=12+1=13at=13*9.81*104 N/m2 10.2. PHNG TRNH C BN CA TNH LC HC CHT LNG Khi nghin cu tnh lc hc ca cht lng, ngi ta coi cht lng trng thi yn tnh tng i ngha l khi cht lng trong mt khng gian c gii hn cng chuyn ng vi bnh cha n, cn cc phn t trong khi th khng c chuyn ng tng i vi nhau. 10.2.1. p sut thy tnh Khi cht lng trng thi tnh chu hai lc tc dng: lc khi lng v lc b mt. Khi =const th lc khi lng t l thun vi th tch khi cht lng v tc dng ln mi phn t ca th tch khi cht lng . Lc tc dng ln b mt khi cht lng gi l lc b mt. Xt mt nguyn t b mt F trong cht lng, th b mt nguyn t s chu mt p lc ca ct cht lng cha n l P theo phng php tuyn. Khi p sut thy tnh s l:

pt

F

lim

P 0 F

(10.7)

p sut thy tnh c c im: Tc dng theo phng php tuyn v hng vo trong cht lng. V nu theo phng bt k v c lc ko ra pha ngoi th s lm cht lng chuyn ng, tri vi iu kin cn bng tnh ca cht lng. Ti mt im bt k trong cht lng c gi tr bng nhau theo mi phng. L hm s