tkmh khi.hoang

8/2/2019 tkmh khi.hoang

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Thit k mn hc kim sot nhim khng kh v ting n

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Thit k mn hc.

Kim sot nhim khng kh v ting n

Tn sinh vin: ng Vn Hong

Sinh vin lp: K thut mi trng K47.

MSSV : 0605758

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ng Vn Hong k thut mi trng k47


2/38


------------------------------------------------------------------------------------------------------------ bi:

Thit k h thng x l bi nh my Xi mng A

- Cng sut: 20000 tn Clinke/nm

Lu lng kh thi: 350m3/h

Yu cu ca thit k mn hc

KIM SOT NHIM KHNG KH V TING N

1. t vn

- Nu tm quan trng ca vn nghin cu

- Tng quan v vn nghin cu

- Tnh ti lng kh nhim tnh nng cc kh nhim

- Yu cu: + Kh thi sau x l t quy chun QCVN 23: 2009/BTNMT

(loi B2)

+ Nhit kh sau x l:


3/38


------------------------------------------------------------------------------------------------------------4. Tnh ton cc thit b

Cc thit b phi c tnh v:

- Kch thc ca thit b: B, L, chiu cao lm vic, chiu cao thp,

- Hiu sut lm vic

- Lng nguyn vt liu, cht xc tc cn thit cho qu trnh (nu c)

- C th t t cc gi thuyt (ph hp vi thc t) qu tnh tnh ton n

gin hn

5. Tnh ton cc thit b ph tr

- ng khi

- Qut ht

- ng ng

- Tnh tr lc ca h thng

6. Kt lun.

I. t vn :

1- Nu tm quan trng ca vn nghin cu:

- X l khi thi ca nh my xi mng nhm bo m v sinh cho mi trng

khng kh, bo v sc khe cho ngi lao ng.- Tng cng an ton lao ng, bo m cht lng sn phm;

- Gim s mi mn my mc, tng hiu sut s dng, gim chi ph bo tr

my mc;

- Bo m s lm vic chnh xc v kin tc ca cc thit b cng ngh;

2- Tng quan v vn nghin cu:

3- Tnh ti lng kh nhim, tnh nng cc kh nhim.

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4/38


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M u:

c trng ca cht thi ngnh cng nghip ximng l nhim bi gy tc

hi ln vi mi trng v sc kho con ngi, bi l ngun nhim ch yu cn

c x l. Do vic thit k mt h thng x l bi trong nh my trc khi

thi ra mi trng khng kh l ht sc cn thit m bo s pht trin bn vng

ca ngnh cng nghip ximng. Nh my sn xut ximng A vi cng ngh l

quay theo phng php kh nn sn lng ximng ln v nhim t hn nhiu so

vi cng ngh l ng. Trong n cp ti h thng x l bi ximng bng

thit b lc bi tay o.

Tc hi ca bi xi mng: Nhn chung, bi xi mng khng gy bnh bi phi nhng

nu trong bi xi mng c trn 2% Silic t do v tip xc lu trong thi gian di th

c th pht sinh bnh bi phi. ng vt ht th bi xi mng khng gy bin i

bnh l cp tnh hoc mn tnh no. Tuy nhin bi xi mng bm trn l cy lm

cho thc vt khng quang hp c. Bi clinker v bi xi mng c kh nng theo

gi pht tn trong khng kh v sa lng xung nc v mt t. Khi sa lng xungmi trng nc s lm tng c ca nc v gy tc ng xu ti thy sinh

vt. Khi sa lng xung mi trng t s lm cho t ai xung quanh khu vc b

chai cng, kh nng gi nc km i, t tr nn ngho dinh dng, b thoi

ha

Thit k h thng x l kh thi l dng bi tp nhm gip cho sinh vin mi

trng va vn dng cc kin thc hc vo qu trnh thit k l thuyt, va c

nhn thc c cng vic cn phi lm sau khi ra trng.

Vi m hnh v cc s liu gi nh, mc tiu ca bi tp ln l thit k h

thng x l bi, a ra s cng ngh x l bi ca nh my xi mng.

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5/38


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Phn I: Nhim v thit k.

H s nhim v ti lng nhim khng kh t cc ngun thi ca sn xut

xi mng theo phng php kh:

Hot ng H s nhim, kg/tn clinke. Ti lng nhim.(Tn/nm).H s nhim x lng clinke sn xuttrong mt nm.

BiA Bi B SO2 NO2 Bi A Bi B SO2 NO2

D tr than (Silo) 0,1 0,5 140 700

p, nghin, sng 0,102 10,18 142 14252

D tr nguyn liu 0,14 0,14 196 196p sng nguyn liu 0,02 4,2 280 5880

Vn chuyn bng bng ti 0,075 1,5 105 2100

Nung Clinke 0,34 1,28 1,02 2,15 476 1792 1428 3010

Lm ngui Clinke 0,048 10,6 67,2 14840

Nghin Clinke 0,05 10,6 70 14840D tr Clinke (Silo) 0,12 5,4 168 7560D tr xi mng 0,13 0,13 182 182

ng bao xi mng 0,01 2,2 14 3080Tng cng 1,135 46,73 1,02 2,15 1589 65422 1428 3010

Vy tng lng bi sinh ra trong mt ngy l: qngy = 46,73.5000 = 233650

(kg/ngy) = 233,650(tn/ngy).

V ch cn tnh trng hp B nn :

Tng lng bi sinh ra trong 1 nm: qnm = 65422 (tn/nm).

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6/38


------------------------------------------------------------------------------------------------------------I.1. Cc cht kh cn x l trong nh my:

STT Tn cht kh Ti lng (kg/ngy)

1 Nhit 2000C

2 Bi 300

3 SO2 4200

4 NOx 3000

5 VOC 50

I.2. C s la chn thit b x l kh thi.

Nng C ca cc thng s nhim lm c s tnh ton nng ti a cho phpca cc thng s nhim trong kh thi cng nghip sn xut xi mng c quynh ti Bng 1 di y:

Bng 1: Nng C ca cc thng s nhim trong kh thi cng nghip sn

xut xi mng

STT Thng sNng C (mg/Nm3)

A B1 B2

1 Bi tng 400 200 100

2 Cacbon oxit, CO 1000 1000 500

3 Nit oxit, NOx (tnh theo NO2) 1000 1000 1000

4 Lu hunh ioxit, SO2 1.500 500 500

Ch thch:

- i vi cc l nung xi mng c kt hp t cht thi nguy s c quy chun

k thut quc gia v mi trng ring.- i vi xng nghin nguyn liu/clinke khng quy nh cc nng CO,

NOx, SO2.

Trong :

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- Ct A quy nh nng C ca cc thng s nhim trong kh thi cng

nghip sn xut xi mng lm c s tnh ton nng ti a cho php i vi

cc dy chuyn sn xut ca nh my, c s sn xut xi mng hot ng trc

ngy 16 thng 1 nm 2007 vi thi gian p dng n ngy 01 thng 11 nm

2011;

- Ct B1 quy nh nng C ca cc thng s nhim trong kh thi cng

nghip sn xut xi mng lm c s tnh ton nng ti a cho php p dng i

vi:

+ Cc dy chuyn sn xut ca nh my, c s sn xut xi mng hot ng

trc ngy 16 thng 1 nm 2007 vi thi gian p dng k t ngy 01 thng 11 nm

2011 n ngy 31 thng 12 nm 2014;

+ Cc dy chuyn sn xut ca nh my, c s sn xut xi mng bt uhot ng k t ngy 16 thng 01 nm 2007 vi thi gian p dng n ngy 31

thng 12 nm 2014;

- Ct B2 qui nh nng C tnh nng ti a cho php cc thng s

nhim trong kh thi cng nghip sn xut xi mng p dng i vi:

+ Cc dy chuyn sn xut ca nh my, c s sn xut xi mng xy dng mi

hoc ci to, chuyn i cng ngh;

+ Tt c dy chuyn ca nh my, c s sn xut xi mng vi thi gian p dngk t ngy 01 thng 01 nm 2015;

- Ngoi 04 thng s quy nh ti Bng 1, tu theo yu cu v mc ch kim

sot nhim, nng ca cc thng s nhim khc p dng theoquy nh ti

ct A hoc ct B trong Bng 1 ca gia QCVN 19: 2009/BTNMT- Quy chun k

thut quc gia v kh thi cng nghip i vi bi v cc cht v c.

.

Cc thng s u vo nh my xi mng A:

- Ti lng bi trong mt gi: qgi= 29206,25 kg/h.

- Th tch kh u vo V = 550 000 m3/h.

- Nng bi: 29206,25/550000 = 0,053102 kg/m3 = 53102 mg/m3.

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8/38


------------------------------------------------------------------------------------------------------------- Khi lng ring bi xi mng: = 2 840 kg/m3.

- Sau x l t QCVN 23: 2009/BTNMT (loi B2)

- Nng bi: 100 mg/m3.

- Nhit ca kh sau khi x l : 100oC.

Phn II: La chn s cng ngh v thit b x

l:

II.1.Xc nh cng ngh v thit b x l kh thi ca nh my:

Cn c vo cc phng php x l, thit b x l, cc cht ph gia, hiu qu x l

ca cc phng php ang c ng dng rng ri hin nay. Cc phng php x

l kh thi cho nh my c la chn nh sau:

X l nhit: bng phng php trao i nhit bng thp trao i nhit.

X l bi: bng phng php s dng thit b lc tay o.

II.2. S cng ngh:

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Thit bx lnhit

Thit bx l bi

Kh thi vo Kh ra


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Phn III: Tnh ton cc thit b x l.

Chng 1: Tnh ton thit b trao i nhit.

gim nhit kh thi xung, chng ta s s dng thit b ni hi thc hin

qu trnh trao i nhit. Bn cht ca qu trnh trao i nhit chnh l qu trnh

truyn nhit gia kh thi v cht lu.C th dng thit b ng chm nhng i vi

kh thi ca nh my xi mng c nhiu bi nn d l tc ng chm, do ta chn

thit b ng cong, trao i nhit ngc chiu.

Qu trnh truyn nhit gm nhng bc sau:

Cp nhit t kh thi n b mt ngoi ca ng.

Dn nhit qua thnh ng

Cp nhit t b mt trong ca ng n nc.

Nhit ca kh thi s gim t 3500C xung cn 1000C. Nc i vo nhit

trung bnh khong 250C v c un p sut cao 10 at, nc si 1780C.

S cu to ca thit b trao i nhit

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10/38


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A

C

B

5

4

1

3 2

A. THP TRAO I NHIT

B. THIT B LM LNH

C. BM

1. CA DN KH VO

2. CA DN KH RA

3. CA V SINH THIT B

4. CA DN NC TI LNH VO THP

5. CA A NC TI NHIT RA KHI THP

6. NG NG DN NC

La chn thit b:

La chn loi thit b trao i nhit l thp trao i nhit kiu ng xon ng

gm c v hnh tr, 2 u hn 2 li ng , cc ng truyn nhit c ghp chc,

kn vo li ng . y v np ni vi v bng mt mt bch c bu lng ghp chc.

Trn v v y c ca ng dn cht ti nhit. Thit b c t trn gi nh

tai hn vo v.

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2000C

1780C

900C

00C


------------------------------------------------------------------------------------------------------------Cht ti nhit lnh l nc s i t trn xung, chy bn trong ng xon, cht ti

nhit nng l kh thi cn lm ngui i bn ngoi ng xon bn trong thp, t di

ln.

Chn loi ng thp c h s dn nhit = 23,2+ W/m., ng knh trong l 10

cm, ng knh ngoi l 10,5 cm.

Chn ch chuyn ng ca cht ti nhit l ch xoy:

Vi nc: n= 0,1- 1 m/s. Chn : n= 0,5 m/s.

Vi khng kh: kk= 2- 20 m/s. Chn : kk= 20 m/s.

Do lu lng kh thi qu ln nn ta chia lu lng ca kh thi ra lm 20 phn

a vo 20 thp trao i nhit . Sau y ta s tnh ton cho 1 thp.

I.1. Tnh ton qu trnh truyn nhit:

Hiu s nhit trung bnh ca hai lu th chuyn ng c th tnh nh i vi

trng hp hai lu th chuyn ng ngc chiu nhau

p dng cng thc :

c

d

cd

tb

t

t

ttt

=

ln

Trong

t1 = t1 - t2c

tc = t1c t2d

Ta c nhit t1 = 2000C, t1c = 900C

t2 = 00C, t2c = 1780C

Suy ra hiu s nhit trung bnh l:

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12/38


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2

1

21tb

tt

ln

ttt

=

=100

172ln

)0100()178`200( =1330C

Nhit trung bnh ca nc l:

01 2n t t 178 0t 89 C

2 2

+ +

= = =

Nhit trung bnh ca kh thi l:

0

k n tbt tt 89 133 222 C= + = + =

I.2 Lng nhit cn trao i v lng nc cn s dng:

Ta c phng trnh cn bng nhit lng cho thp trao i nhit nh sau:

Qk=Qm+Qn+Q1

Trong :

Qk Nhit lng kh mang vo t = 200 oc

Qm - Nhit lng mt mt, ly Qm=10%Qk

Qn - Nhit lng nc nhn.

Q1 - Nhit lng ra khi thit b

a. Nhit lng kh thi mang vo:

Lng nhit do kh mang vo thit b trong mt giy l: Qk = mk .Cp . t1

Trong :

m1 - lng kh thi i vo thit b

Cp - nhit dung ring ca kh thi kJ/kmol.

t1 - nhit ban u ca hn hp kh, t = 200 0C.

Vi mk l khi lng ca kh c xc nh theo cng thc

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13/38


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.k k

m V = , vi th tch khi l tnh c l V =550000

7,6420.3600

= m3/s

Khi lng ring ca khi tnh theo cng thc:

k=V

M.n ii

ni, Mi : s mol v khi lng phn t ca kh i trong khi l;

V: th tch ca hn hp kh

Vi cc gi tr trn thay vo c k = 1,2 kg/m3.

=> . 7,64.1,2 9,168k km V = = =

kg/s = 33005 kg/h.

b.Tnh nhit dung ring ca khi l :

Cng thc tnh nhit dung ring ca hn hp kh:

C = c1x1 + c2x2 + c3x3 + ...+cnxn

Trong :

c1, c2, c3 l nhit dung ring phn t ca cc cu t thnh phn.

x1, x2, x3 l thnh phn ca cc cu t kh, phn mol.

Trc ht ta phi xc nh nhit dung ring ca cc cu t thnh phn:

cp = a0 + a1T - a2.T -2

Cc gi tr a0, a1, a2 c xc nh theo bng sau:

Bng 3 Cc h s ca hm nhit dung ring

Cht a0.10 a1.104 a2.10-4

SO2 17,78 2,671 3,183

NO2 23,47 5,98 4,91

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14/38


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Suy ra nhit dung ring phn t ca cc kh thnh phn vi nhit trung bnh ca

khi l l:

ttb = 222 + 273 = 4950

K v % mol ca cc cu t trong hn hp kh.

Cu t SO2 NO2

Cpi(kj/kg.) 1,78 2,44

xi 0,25 0,75

Vy nhit dung ring ca hn hp kh l:Cp = c1x1 + c2x2 + c3x3 + + cnxn = 1,78.0,25 + 2,44.0,75 = 2,275

kJ/kg.

Vy: Lng nhit do kh mang vo thit b trong mt giy l:

Qk = mk .Cp . t1 = 9,168.2,275.200 = 4171kJ/s

Nhit lng mt mt: Qm = 10%.Qk = 417 kJ/s

c. Nhit lng kh thi mang ra:

Lng nhit m hn hp kh mang ra l:

Q1 = m1 . Cp . t1c

Vy nhit lng kh mang ra l:

Q1 = m1 . Cp . t1c = 9,168 . 2,275 . 100 = 2086 kJ/s

Vy nhit lng cung cp cho nc l: Qn = 4171 417 2086 = 1668 kJ/s

= 3984 kcal/s

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15/38


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Lng nhit nc nhn tnh theo cng thc:

Qn = Gn[Cn(ts-tv)+r] kcal/s

Vi Qn= 3984 kcal/s.

Nhit dung ring ca nc: Cn = 1,047 kcal/kg..

Nhit ban u ca nc: tv = 00C.

Nhit ho hi ca nc 10 at: r = 482,1 kcal/kg

Vy ta c lng nc cn cho qu trnh l:

=+

=482,10)-1,047(178

3984G 6 kg/s

Ta c khi lng ring ca nc l: = 966kg/m3

Lu lng nc vo thit b: V=6.3600/966 = 22,5m3/h.

Theo thc t lng nc a vo thit b lm ngui kh khng c truyn

nhit hon ton m ch t mt hiu sut nht nh. Gi s ch t hiu sut l 80%

do vy lng nc thc t cn a vo thit b l =

80

100.5,2228(m3/h)

Vy: Lng nhit cn trao i l: 3984 kcal/s.

Lu lng nc vo thit b l 22,5 m3/h.

I.3 Xc nh h s truyn nhit:

Ta c d2/d1 = 10,5/10 < 2 nn h s truyn nhit qua vch tr c th c tnh

nh vch phng nh sau:

1 2

1

1 1K

=

+ +(W/m2.)

Trong :

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16/38


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- h s dn nhit ca vch: = 23,2 W/m.

1 H s cp nhit ca kh thi.

2 H s cp nhit ca nc chy trong ng.

dy ca vch, = 0,005 m.

a. H s cp nhit ca kh thi:

H s cp nhit tnh theo cng thc:

1

1

kNu

d

=

Trong :

k h s dn nhit ca kh thi.

k = B.Cp.

Khi l l hn hp thnh phn nhiu nguyn t nn B =1,72

=> k = 1,72.2,275.103. 430 x 10-7 = 0,17 W/m.

d2 ng knh ngoi ca ng.

Nu chun s Nussel. Xc nh theo cng thc:

Nu=0,41.Re0,6

.Pr0,33

.A.R [3]R=(s1/s2)1/6=(1,05)1/6=1

i vi khi tiu chun Pr t thay i theo nhit nn A=1

Vi kh thi coi l kh nhiu nguyn t l Pr =1

Chun s Reynol : 2Re kk

d

=

Vi: k

- vn tc ca kh trong thit b, k

= 15 m/sd2 k ngoi ng.

k nht ng lc, vk=k/k.

k = 1,2 kg/m3.

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17/38


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k xc nh theo cng thc :

1 1 1 1 2 2 2 2

k

1 1 1 2 2 2

m . . M .T m . . M .T

m . M .T m . M .T

+

=

+

Trong :

k : nht ca hn hp kh nhit ttb v p sut kh quyn.

1 , 2 , - nht ca cc cu t nhit ttb.

m1, m2, - Nng phn th tch ca cc cu t.

M1, M2, - Trng lng phn t ca cc cu t.

T1, T2, - Nhit ti hn ca cc cu t

Cc gi tr Mi, Tthi, v ii TM . c xc nh theo bng sau:

Bng 4 Gi tr ii TM . ca mt s kh

Cht Mi mi Ti ii T.M

SO2 64 0.25 430,5 166

NO2 46 0.75 431,2 141

nht ca cc cu t 495 oK (Ns/m2)

Cu

tSO2 NO2

i215,8.10-

7 275,4.10-7

Thay cc gi tr vo cng thc trn ta c: k = 258,6 x 10-7N.s/m2

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18/38


------------------------------------------------------------------------------------------------------------=> k = 258,6 x 10-7/1,2 = 215,5. 10-7 m2/s.

=> 2 715.0,105

Re 73086215,5.10

k

k

d

= = =

Vi Re = 83627

V Re >104 nn nc chy ri trong ng.

H s to nhit ca nc c xc nh theo cng thc:

Nu=0.021.Re0.8.Pr0.43.A.1.R

Do h s ta nhit ca nc n ln hn rt nhiu ca khi nn nhit ca vch

ng bn trong tw hu nh bng nhit d ca nc: tw= tn v vy : A=(Pr/PrT)0,25 1

H s ph thuc vo t s l/d ca ng, y chiu di ng: l >50d nn 1=1

V phn un cong nh so vi chiu di ng nn c th b qua nh hng ca ng

un cong, R=1

Vy ta c Nu = 0.021 x (73086)0.8 x (1.5)0.43 = 194,5.

=> 11

194,5.0,17330

0,1

kNu

d

= = = W/m.

b. H s cp nhit ca nc:

H s cp nhit ca nc c xc nh theo cng thc:

2

1

nNu

d

=

Trong :

n h s dn nhit ca nc, n = 0,68 w/m.d1 ng knh trong ng, d1 = 0,1 m.

Nu=0.021.Re0.8.Pr0.43.A.1.R

Trong :

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19/38


------------------------------------------------------------------------------------------------------------Pr = 1,5, chun s Prandtl, c trng cho tnh cht vt l ca mi

trng.

A = (Pr/ PrT)0,25 1 (do nhit bn trong vch nhit nc).

R= 1, v phn un cong nh so vi chiu di ng nn c th b qua

nh hng ca ng un cong.

Chun s Reynolt: 1Re nd

=

Vi: n = 0,5 m/s

d1 ng knh trong ng, d1 = 0,1 m.

n nht ng hc ca nc, vn=n/n, nhit tntb = 89 0c, ta

c nht ca nc: n=0.3202 x 10-3Ns/m2, khi lng ring ca

nc: n=966 kg/m3 nn :

n = 0,33. 10-6 m2/s

Vy61

6

0,5.0,1Re 0,15.10

0,33.10

n d

= = =

Vi Re = 0,15.106 , (l/d) > 50 nn h s hiu chnh = 1.

=> Nu = 0,021.(0,15.106)0,8.1,50,43 = 346.

Vy : H s cp nhit ca nc l:

2

1

346.0,682353

0,1

nNu

d

= = = w/m2.

Nh vy h s truyn nhit qua vch tr:

1 2

1 1272

1 1 1 0, 005 1

330 23,2 2353

K

= = =

+ + + +W/m2.

I.4 Xc nh b mt trao i nhit:

Tng din tch b mt truyn nhit ca cc ng:

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20/38


------------------------------------------------------------------------------------------------------------

t.k

QF

=

Trong :

Q lng nhit trao i, Q = 1668 kJ/

K h s truyn nhit, K = 272 W/m2

.ttb chnh lch nhit trung bnh, ttb = 133 0c.

=> 46133.272

10.1668

.

3

==

=tK

QF m2.

I.5. Xc nh cc kch thc chnh ca thit b:

S ng un khc:

2 2

1

4 4 16 40,1 0, 5 966

n

n n

Gnd

= = =

ng

Vi tng b mt trao i nhit nh trn th tng chiu di 1 ng s l:

225,0.1,0.4

46

. 221===

dn

Fl

(m)

Chn chiu di 1 ng un khc l 2m, vy s lp ng l : m = 22/2 = 11 (lp ng).

Gi khong cch gia 2 lp ng un khc l s1 = 2,1.d2 = 2.0,105 0,22 (m).

Vy chiu cao trao i nhit l : h = 11.s1 = 11.0,22 = 2,4 (m).

Vy chiu cao ca thp l : H = h + hnh + hy = 2,2 + 0,25 + 0,25 = 2,9 (m).

Gi khong cch gia hai ng un khc lin k l s2 = 2.d2=2.0,105 =0,2(m).

Chiu rng thp B= 1,2m. Chiu di L=2,5

Cc thng s ca 1 thp trao i nhit:

Lng kh vo 7,64 m3/s

Lng kh ra 7,64 m3/s

Lng nc vo 75 m3/h

Nhit kh vo 200 0C------------------------------------------------------------------------------------------------------------



21/38


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Nhit kh ra 90 0C

Chiu rng 1,2m

Chiu cao thit b 3,5m

S ng un khc 4Chiu di 2,5m

Chng II : Tnh ton thit b lc bi :

Trc ht ta i tm hiu s cng ngh sn xut Clinker v ximng c th thy

c cc khu pht sinh ra bi :

II.1. S cng ngh :

a. S cng ngh sn xut Clinker :

Ngun gc gy nhim khng kh trong qu trnh sn xut Clnker gm :

- Bi nguyn liu ( vi, t st, laterite, ct) pht sinh trong qu trnh vn

chuyn, d tr trong cc kho, bi cha.

- Bi nguyn liu sinh ra trong qu trnh vn chuyn trn cc bng ti, gu nng,

mng trt, phu, cn nh lng, rt, nhgin, trn

- Kh thi sinh ra t ng khi l nung Clinker c cha bi, CO, CO2, SO2, NOx

- Bi Clinker trong qu trnh vn chuyn Clinker ti Silo, rt Clinker t Silo xung

bng ti

------------------------------------------------------------------------------------------------------------

ng Vn Hong k thut mi trng k47Clinker tiu

chun d < 30mm

t st. vi (Laterite)

Bng tiBng nh

lng

My nghinbi Qut ht

My coSilo ngnhtSilo tn trBnh bm Cn nhlng

Thp trao inhit

Clinker Qut ht

L con Ci p


22/38


------------------------------------------------------------------------------------------------------------

b. S cng ngh sn xut xi mng:

------------------------------------------------------------------------------------------------------------


-Phngtin nhn-Kho

My ngbao

Silo ngbao

Bm kh nnPhn lykh ng

Gu nng

My nghinbi

Bng tinh lng

Gu mcBng ti

-Clinker-Thch Cao-Puzoland


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------------------------------------------------------------------------------------------------------------

Ngun gc gy nhim khng kh trong qu trnh sn xut ximng gm:

- Bi Clinker v ph gia (thch cao, puzoland) trong khu vc my p, my nghin

bi, my sng, my phn ly v h thng vn chuyn

- Bi ximng sinh ra trong qu trnh ng bao.

- Bi ximng sinh ra trong qu trnh vn chuyn ximng bao thnh phm ln oto,

nh kho

II.2. Tnh ton thy lc.

Bi pht sinh trong nh my bao gm t cc khu: D tr than (Silo); p, nghin,

sng ; D tr nguyn liu; D tr Clinke (Silo); D tr xi mng; ng bao xi

mng; Vn chuyn bng bng ti;Nung Clinke; Lm ngui Clinke;Nghin Clinke;

p sng nguyn liu.

a. Cc thng s tnh ton:

- Lu lng ht ti:

+ D tr than (Silo): 6894 (m3/h).

+ p, nghin, sng : 118 140 (m3/h).

+ D tr nguyn liu: 3215 (m3/h).

+ D tr Clinke (Silo): 63 428 (m3/h).

+ D tr xi mng: 2988 (m3/h).

+ ng bao xi mng: 25393 (m3/h).

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+ Vn chuyn bng bngti: 18097 (m3/h).

+ Nung Clinke: 18614 (m3/h).

+ Lm ngui Clinke: 122 394 (m3/h).

+ Nghin Clinke: 122 373 (m3/h).

+ p sng nguyn liu: 48 489 (m3/h).

- Vn tc kh thi trong ng dn kh thi n thit b lc tay o bo m yu cu k

thut kinh t l: 18 20 (m/s), chn v = 18 (m/s).

- Ming ht:

- Chc ba nhp dng:

- Cn thay i tit din:

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------------------------------------------------------------------------------------------------------------

- Chp ht:

Chn chp ht hnh ch nht: F = 0,61 0,7 = 0,427 m2.

Vn tc ti ming chp ht l 1,1 m/s.

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------------------------------------------------------------------------------------------------------------

b. S tnh ton:

------------------------------------------------------------------------------------------------------------


D trximng

ng baoximng

D trClinker

NghinClinkerLm ngui

Clinker

NungClinker Vn chuyn bng bng ti

p sngnguyn liu

p nghin

sng

D tr than

D trnguyn liu

2

14

8

6

5

7

3

11

10

4

9

16

12

15

13

17

1

Ming thukh chnh

18

21

20

19

6

14


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------------------------------------------------------------------------------------------------------------Ta c bng di cc nhnh nh sau:

Khong

cch

di

(m)

Lu

lng

(m3/s)

ng

knh

(mm)

Re H s ma

st

=64/Re

/d t=.l/d

1-3 10,51,915 100 83526

0.00077

0.0076

6 0.080

2-3 10,70,893 90 75174

0.00085

0.0094

6 0.101

3-7 5,42,8 120 100232

0.00064

0.0053

2 0.029

4-5 5,432,8 250 208816

0.00031

0.0012

3 0.007

5-6 5,313,5 150 125290

0.00051

0.0034

1 0.018

5-6 5,746,3 300 250580

0.00026

0.0008

5 0.005

6-7 3,851,3 320 267285

0.00024

0.0007

5 0.003

6-8 10,25 150 125290

0.00051

0.0034

1 0.035

7-12 5,654 350 292343

0.00022

0.0006

3 0.004

11-12 4,739 280 233874

0.00027

0.0009

8 0.005

9-11 11,2 5,17 150 125290 0.00051 0.0034 0.038

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------------------------------------------------------------------------------------------------------------

1

10-11 5,834 280 233874

0.00027

0.0009

8 0.006

12-15 4,9

93,3 500 417633

0.00015

0.0003

1 0.002

13-14 4,834 250 208816

0.00031

0.0012

3 0.006

14-14 2,717,6 200 167053

0.00038

0.0019

2 0.005

14

-15 6,5

51,6 300 250580

0.00026

0.0008

5 0.006

15-20 11,6145 550 495396

0.00013

0.0002

3 0.003

16-17 5,27 120 100232

0.00064

0.0053

2 0.028

17-19 5,0

0,83 90 75174

0.00085

0.0094

6 0.047

18-19 3,80,83 90 75174

0.00085

0.0094

6 0.036

17-20 57,9 120 100232

0.00064

0.0053

2 0.027

20-21 4,8 153 550

Trong bng trn ta tnh ng knh ng thu bng cng thc sau:

------------------------------------------------------------------------------------------------------------



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------------------------------------------------------------------------------------------------------------

0,785.

Qd

v=

Trong : Q: Lu lng kh i qua ng, (m3/h).

v: Vn tc kh trong ng, (m/s). Chn v = 18 (m/s).

Ta chn nhnh chnh l nhnh di nht tnh ton: 2-3-7-12-15-20-21.

Cc nhnh ph:

1-3

4-5-6-7.

9-11-12.

13-14-15.

16-17-20.

18-19-17-20.

*. Nhnh chnh:

- on 2-3: D tr nguyn liu c: Q = 3215 (m3/h), l2-3 = 10,7 m, chn v = 18

(m/s).

+ p sut ng: P =2 2. 18 .1,2

19,842. 2.9,8

kv

g

= = (N/m2).

+ H s sc cn cc b trn on ng:

Ct i hng 90o : 1 ci vi R = 2d, = 0,15.

Ming ht: = 0,5.

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------------------------------------------------------------------------------------------------------------Cn thay i tit din vi = 300:

221 1

2 2

120( ) 1,728

100

F d

F d = = =

; = 0,1

Chc 3 ng chnh vi gc r = 300

:

Qo/Qc=1,915/2,8 = 0,68.

F0/Ft = (d0/dt)2 = (90/100)2 = 0,729 suy ra t = 3,23

Vy tng tr lc cc b: = 4,29

+ Tn tht p sut:

P = (t + ).P = (0,101 +4,29).19,84 = 87(N/m2).

Cc on ng khc lm tng t, cui cng ta tnh c :

Tng tn tht p sut t ng ng n thit b x l:

P = 9 258 (N/m2).

II.3. Tnh thit b lc tay o:

II.3.1. Tnh ton cng ngh:

- Nhit khng kh l tk = 350C, khi lng ring k = 1,146 (kg/m3).

- Nhit kh bi tb = 1000C, khi lng ring b = 2840 (kg/m3).

- Lu lng kh cn lc: do lu lng kh qu ln nn ta s phn lu lng kh cn

lc bi ra 10 phn bng nhau cho qua 10 thit b lc tay o.

Q = 550000/10 = 55000 (m3/h).

- Nng bi vo thit b lc 53102 mg/m3.

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31/38


------------------------------------------------------------------------------------------------------------- Cng lc: i vi bi ximng: v= 100 200 (m3.m2.h). Chn v = 200

(m3.m2.h).

- Nng bi ximng cho php thi ra mi trng theo TCVN 5939-2005 loi B

l: Ctc = 100 (mg/m3).

- : Hiu sut lm vic ca b mt lc:

%8,9953102

10053102=

=

=

v

tcv

C

CC .

- Din tch b mt lc:

)(55,275998,0.200

55000

.2

mv

VF == .

- S ng lc tay o:

. .

Fn

D l= ;

Trong :

D: ng knh ng tay o, D = 0,2 0,4 m, chn D = 0,4 m.

L : Chiu di lm vic ca ng tay o, l = 2 3,5 m, chn l = 3,5 m.

Thay s ta c:

625,3.4,0.14,3

55,275=n (ng).

S ng thit k bao gm c nhng ng hon lu l: n = 62 + 2 = 64 (ng).

- Tr lc ca thit b lc:

p = A.vn, (N/m2).

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------------------------------------------------------------------------------------------------------------Trong : A l h s thc nghim i vi tng loi vi, k n mi mn, bn..

A = 0,25 25 chn A = 3.

n: l h s thc nghim, n = 1,35 1,30, chn n = 1,30.

Thay s ta c:

0,33.200 14,7p = = (N/m2).

- Chn thit b lc ti vi c h thng c kh gi bi.

- chn thi gian thu bi l 30 pht, gi bi t 1 n 5 pht

- Chn vi len lm ti vi.

- Phn b ti lc tay o: 88 (8 ti theo hng ngang, 8 ti theo hng dc).

- Lng kh i vo thit b lm sch:

Gv = Q.k = 55000.1,146 = 63030 (kg/h).

- Nng bi trong h kh tnh theo % khi lng i vo thit b tay o:

yv = Cv/k = 0,053102/1,146 = 4,6 %.

- Nng bi trong h kh tnh theo % khi lng i ra thit b lc tay o:

%10.2,9)998,01.(6,4)1( 3=== vr yy

- Lng h kh i ra khi thit b:

6013610.2.9100

6.4100.63030100

100. 3 =

=

= r

vvr y

y

GG (kg/h).

- Lu lng kh sch hon ton:

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------------------------------------------------------------------------------------------------------------

60130100

6.4100.63030

100

100=

=

= vvs

yGG (kg/h).

- Lu lng bi thu c:

Gb = Gv Gr= 63030 60136 = 2894 (kg).

II.4. Tnh cu to thit b:

- Phn b ti lm 8 hng, mi hng 8 ti.

- Chn khong cch:

+ Gia cc ti l 80 mm.

+ Gia cc hng l: 80 mm.

+ Gia ng tay o ngoi cng n mt trong ca thit b l: 80mm.

- Din tch b mt thit b:

ST = [8.0,4 + 9.0.08]2 = 15,4 (m2) 16 m2.

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------------------------------------------------------------------------------------------------------------- Kch thc thit b:

+ Chiu di: 4 m.

+ Chiu rng: 4 m.

+ Chiu cao: H = Phn thn + Phn phu thu bi + Chiu cao cn li = 2500 + 800

+ 1700 = 6000 (mm).

Kh thi sau khi qua thit b lc tay o s c a n ng khi v thi ra ngoi

mi trng.

Phn IV: TNH CC THIT B PH TR.

Chng I: Tnh chiu cao ng khi:

I.1. ng knh ng khi:

Chn vn tc kh trong ng khi: v = 15 m/s.

Dok =550000

3,5 .0.785. 3600.0,785.15

Qm

v= = =

I.2. Chiu cao ng khi:

3

. . . .

. .cp

A M F m nH

C Q T=

.

Trong :

A: H s ph thuc vng kh hu; A = 200 i vi kh hu nhit i.

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35/38


------------------------------------------------------------------------------------------------------------Ccp: Nng cho php ca bi trong mi trng xung quanh;Ccp = 0,2

mg/m3 theo TCVN 5937-2005.

M: Lng cht thi thot ra trong ng khi trong 1 giy.

M = Cr . Q = 0,1.550000/3600 = 15,3 g/s.

F: H s ph thuc trng thi cht kh, F = 2 i vi bi v hiu qu x

l l 99,4%.

T: Hiu s gia nhit khi thi v nhit kh quyn: T = 100

35 = 650C.

m, n: Cc h s khng th nguyn tnh n iu kin thot kh thi t cng khi.

m = 0,37; n = 1,05.

Thay s ta c:

3

200.15,3.2.0,37.1,0512 .

0,2. 550000.65H m= =

Chng II. Tnh qut.

t qut trc ng khi, sau thit b lc ti vi:

Chn chiu di ng ng dn kh t thit b lc ti vi vo ng khi l = 7.5 (m).

II.1. Tn tht p sut:

Tn tht p lc ton h thng = Tn tht p lc on ng + Tn tht p lc n

thit b + Tn tht p lc ng khi:

+ Tn tht p lc on ng dn kh n thit b x l:

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36/38


------------------------------------------------------------------------------------------------------------P1 = 9258 (N/m2).

+ Tn tht p lc on ng dn kh t thit b x l n ng khi:

Ta c lu lng kh ra l: Qr= Gr/k = 60136/1,146 = 52475 (m3/h).

Chn vn tc i trong ng l: v = 15 (m/s).

Suy ra ta c:

d= =v

Qr.785,0

.10=

15.785,0.3600

52475.103,52(m).

Tr s /d = 0,024.

H s sc cn tng ng trong on ng thng: t = .l/d = 0,18

p sut ng: P =2 2. 15 .1,146

13,152. 2.9,8

kv

g

= = (kg/m2).

H s sc cn cc b trn on ng: = 0,5 + 0,3 = 0,8.

Trong : Ming vo ng sc cnh: = 0,5; Gc ln 900 2 ci vi R = 2.d = 0,3.

Suy ra: P2 = (t + ).Pd = (0,18 + 0,8).13,15 = 13 kg/m2 = 127,4 (N/m2).

Vy tng tn tht ng ng: P = P1 + P2 = 9258 + 127,4 = 9385,4 (N/m2).

- Tn tht p lc thit b:

1,3. 2,5.120 1261,47ntbp A v = = = (N/m2).

- Tn tht p lc ng khi:

Chiu cao ng khi: H = 12;

Chn vn tc trung bnh trong ng khi l: 15 (m/s).

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37/38


------------------------------------------------------------------------------------------------------------ng knh ng khi: 3,5m.

Lm tng t ta c: Pk = 173,86 (N/m2).

Vy tr lc ca ton h thng: P = P1 + P2 + Ptb + Pk = 10820 (N/m2)

11000 (N/m2).

II.2. Cng sut qut:

. 550000.110002498 w.

1000. . 3600.1000.0, 6.0, 95q q tr

Q PN k

= = =

Vi: q = 0,6- hiu sut qut.

th = 0,95, hiu sut truyn ng trc tip vi trc ng c.

Phn V: KT LUN.

Do s hn ch v thi gian cng nh ti liu nn bi tp ln thit k mn hc

x l kh khng th trnh khi nhng thiu st trong qu trnh tnh ton. Tuy nhin

qua bi thit k mn hc ny cng gip sinh vin bc u nm bt v cng

ngh x l kh thi hin nay v tch ly nhiu kinh nghim cho qu trnh i lm sau

ny.

Em cng xin chn thnh c gio Ths. V Kim Hnh gip em trong qu trnh

hon thnh bi thit k mn hc ny.

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