Chapter5 Loc

8/14/2019 Chapter5 Loc

1/30

1

Visu

Loc

Muc tieuKh cac hat mn vo c va hu c.Trong x ly nc, loai bo bong cn mn khong lang c be lang

Trong XLNT, thng s dung cho x ly bac cao oi hoi SSva COD thap

2

Visu

Loc trong lc

Nguyen tac:S dung vat lieu hat, co cot ap nc tren lp VLLocVat lieu hat: cat, than anthracite, than HT, cat tao, VL hon hp.

Mang thu nc ra

Vao

ra

xa loc au

Nc ra ngc

VL loc

Soi

Dan phan phoi

Nc xa ra

Cot ap nc trenbe mat cat

kh nen


2/30

3

Visu

Phan loai:

Loc cat cham (SSF) - VL 1 lpLoc cat nhanh (RSF) ket hp nhieu loai Vlieu: nhieu lp; hailp; loc keo tu tiep xuc.

Thanh phan :Lp vat lieu co nh;VL noi;

Single mediaMultimedia

Loc trong lc

4

Visu

C Che Loc

C che bat gi:Be loc cat nh Tb bat gi c hoc: Ch co hat co ng knhhat > khe h gia cac hat c gi lai.


3/30

5

Visu

Khi cac hat ln bt dan khe rong gia cac hat, cac hat mnco kch thc nho hn b bat gi;

C Che Loc

6

Visu

Be mat lp loc nhanh chong b bt TTAL tang va thuy lckeo cac hat mn qua lp loc, tang o uc.

h

C Che Loc


4/30

7

Visu

h

C Che Loc

Be mat lp loc nhanh chong b bt TTAL tang va thuy lckeo cac hat mn qua lp loc, tang o uc.

8

Visu

Khi quan sat cac can co KT nho hn khe rong hat cung cgi lai lp VlcatViec bat gi cac hat can mn xay ra ngay ca khong co hat ln.Nh vay c che gi lai gi vai tro quan trong.

C Che Loc


5/30

9

Visu

C che hap phu:

ong hoc hap phu:Gi vai tro chnh loc va lp VL loc ro.Hieu qua loc hap phu phu thuoc vao tnh chat be mat:

Loc cat;Can l lng.

Cong them kha nang dan dnh vao hat khi can tiep xuc bemat vi hat VLL.Van chuyen ti v tr o hat can tiep xuc vi be mat/hoacen gan.

C Che Loc

10

Visu

Dp/2

Dp

C che tiep xuc:Khi hat can theo dong nc en gan satbe mat hat VLL can dnh vao be matNeu can co ng knh hieu qua "Dp" dichuyen theo dong en be mat VLL Kcach (Dp/2) co c hoi hap thu.

Van chuyen can ti VL loc


6/30

11

Visu

Lang:Can tach khoi dong di tac ong cuatrong lc dan en s khac nhau giatrong lc va lc ay noi.


12

Visu


Khuech tan:Do chuyen ong Brown (chay tang), hieuqua tiep xuc va lang lam gia tang kchthc hatHieu qua khuech tan Brownian tang khigiam KT hat.


7/30

13

Visu

++

++ + +

+

+

Hap dan ien tch:

--

-

-

C Che Loc

14

Visu

Tao bong:Trong khi nc chay qua hat VL loc,gradient van toc tang cac hat canmn tao thanh floc tang hieu qua tiepxuc va lang.

C Che Loc


8/30

15

Visu

Hien tng loc VL ro

Van chuyen:1. Chuyen ong brown2. Lang3. Tiep xuc

Bam dnh :1. C che gi lai2. hap phu (hoa/ly):

Hoa tao cau noi/tng tac hoaVat lieu - Tnh ien; Electrokinetic; Van-der-Walls.

3. sinh hoc (ch be loc cham - Schmutz desk)Phn tch:

1. Lc cat thuy lc2. S va cham cac hat (ac biet oi vi cong suat TXL ln)

16

Visu

Tieu chuan chon la loc

1. Hnh dang hat VLL:Tho (VL nghien)Tron (cat song va bien)oi vi hat co [P10] nho, ton that AL cao hn dv cac hat VLLnhan hn cac hat VL nghien khong eu.

2. rng:Khoang khe h.

3. An mon do acid:

Mat VLL do khong the chu ng MTrng acid caochang hannh kh an mon CO2.

4. Tnh de v:

VL chon u ben chac khong b v vun.

Tnh de v phu thuoc vao che o van hanh


9/30

17

Visu

Chon la kch tho hat VLL

Cat thien nhien (song/b bien) co the cha:

cat thomn giam t le chenh lech gia cac hatKhong eu

ieu nay co the thc hien bang cach ray sang cat, kh iphan cat mn [P10(Fine) va cat tho P60(Coarse)].

< P10 qua mn> P60 tho

60%

10%

x

P10 P60

kch thc sang

(mat sang)

% khoi lng qua sang

sau nghien trc khinghien)

18

Visu

Tnh Chat VL Loc va PP Chuan BLoai VL Loc:

Silica thien nhieen;Than nghien anthracite (than a);Magnetite nghien (quang);Hat THT;VL tong hp hnh cau bang nhakhac (charcoal, coconut hulk, etc.)

KT VLLoc:c xd bang ng cong % khoi lng hat qua bo ray sang tieu chuan.

Phng phap:100 gms VL- say kho trong 4 gi 120C - cooled.Cho vao bo ray va ghi nhan lng gi lai tren moi sangTnh toan trong lng VL loc qua moi sang.


10/30

19

Visu

He so ong nhat (CU):Noi len tnh chat phan bo hat, lng s dung, mat o lp VL loc.

KT trung bnh hnh hoc:

50P=10

60P

PCU =

(approximately)

KT hieu qua:

E = P10(10 % from the graph)

Tnh Chat VL Loc va PP Chuan B

tai o chat lng nc at hieu qua

20

Visu

Loc cat cham (SSF)

Lch s:SSF c s dung vao au TK19th. au tien s dung cho capnc nam 1804 ScotlandSSF s dung pho bien trong suot TK 19th.en nam 1897,be loc cat nhanh c s dung Kentucky


11/30

21

Visu

Tphan c ban:

Be beton (toi thieu co 2 n nguyen: 1 van hanh, 1 ra).Dan thu nc- gom ong, mng thu nc loc dan en becha nc sachLp soi ngan can cat i vao ong thoat;Co Tb kiem soat lu lng vao va ra e ieu chnh lu lngon nh qua loc.

Mang thu nc ra

cat loc(0.2-0.4 mm )

soi

Onh nhanh khoan lo

750 mm

600-750 mm

350-600 mm

Loc cat cham (SSF)

22

Visu

Mo ta qua trnh: giai oan au, nc qua loc con ban.Hieu qua cua SSF phu thuoc vao viec hnh thanh lp sinh khoihoat tnh tren be mat VLLoc, co o nhtLp nay gi lai can SS va vi khuanMot khi lp nay tr nen day hnh thanh lc can tang TTALnhanh trc khi o uc vt qua gii hanLp loc lam sach bang thu cong (thong thng 1 - 3 thang) va50 - 80 mm cua cat loai boCat d sau khi ra c s dung lai

Van hanh loc cat:Nc i qua lp cat loc t tren xuongieu chnh lu lng on nh bang van khoa/tb ieu chnh

Loc cat cham (SSF)


12/30

23

Visu

Thuan li:Chat lng nc loc rat tot, ham lg Al, Fe, va Mn rat thap;Khong can x ly s boKhong hoa chat s dung;n gian trong van hanh giam chi ph van hanh, khong oi hoican bo co tay nghe;Nc loc co tnh an mon thap;Chu trnh loc tng oi dai

Loc cat cham (SSF)

24

Visu

Bat li

Do toc o loc rat thap dien tch be mat ln, xay dng ln.Hieu qua kh mui kem;Kh uc kem neu o uc> 40 NTU SSF khong nen s dung khi> 40 NTU;Gay mui kho chu do vi sinh (e.g., vi khuan, tao, ruoi, oc, etc.)

Loc cat cham (SSF)


13/30

25

Visu

Be Loc Nhanh (RSF)

Trong RSF, hoat ong vi sinh khong gi vai tro quan trong trong

viec bat gi chat ranC che kh chat ran mn sau khi qua keo tu-tao bong, langChat keo tu co the cho vao be loc e tang hieu qua locTrong RSF, loc toi u khi can tham nhap xuong sau lp cat nhngkhong ra khoi lp cat, lng ln can gi lai trong lp cat.

26

Visu

Be loc nhanh (RSF)


14/30

27

Visu

Be loc nhanh (RSF)

Xa ra congBe cha nc sach

Mang thu nc ra

VL loc

VL

Dan thu nc loc/pp nc ra

Cot ap tren lp cat

ai nc

Be lang

28

Visu

Loc Nhanh (RSF)

Kho khan ban au:Keo tu can thiet e tang hieu qua loc;Chat ban gi lai sau trong lp cat lam sach be matkhong u;Tac loc nhanh, thi gian chu ky loc = 12 24 h, so vi loccham 1-2 thang


15/30

29

Visu

Loai loc nhanh

Loc trc tiep:

Ap dung nc tho co SS thap;Thay oi chat lng nc trong nam khong nhieu;Toc o loc co the thay oi rong =4 - 25 m/hChon la qua trnh can nghien cu them

Nc tho

SCR

RSF

Nc loc

30

Visu

Loc nc qua keo tu-tao bong-lang:Lng ln bong can gi lai be lang;Nc vao loc ch cha lng nho bong can;Chu ky loc dai

tronlang

loc nhanh

tao bong

SCR

CKT

Loai loc nhanh


16/30

31

Visu

Loc tao bong tiep xuc:

Them chat keo tu, tang cng kha nang gi can.Dong chay qua lp vat lieu co tac dung nh be tao bong ehnh thanh bong trong lp VL.

Tron

CKT

SCR

Loc nhanh

Sau loc

Nc tho

Cac polymer ien phan cationic thng c s dung dothe tch bun sinh ra nho khi so vi CKT thong thng.Toc o loc: 4 - 10 m/h

Loai loc nhanh

32

Visu

Thiet Ke Loc NhanhTTAL theo thi gian:TTAL tang theo Tgian (do VL loc b bttac dan)

o uc

e

c

t1

d

b

TTAL, cm150

50

100

a

t1 t2

h1

a: ng TTALb: ng o ucc: u chu ky loc

d: Thi iem mat hieu quae: Gii han o uch1: Ton that ap lc ln nhat cho phep

h

o uc theo thi gian:o uc giam dan va at gia tr thapkhong oi en khi VL loc ban toanbo/cuoi chu ky loco uc tang len cuoi chu ky loc


17/30

33

Visu

Ap lc(cot nc, m)

Chieu cao, m

2 m

2 mA

Ton That Ap Lc Qua Loc

1. au tien lp loc ong nhat (DK hieu qua 0.55 mm).Khi ra ngc lp loc phan tang khong ong nhat. Cat mn (0.3 mm) tren; Cat tho (0.9 mm) pha di.

khong dong chay

2 m

TTAL ban au

hB

B

34

Visu

Ap lc(cot nc, m)

Chieu cao, m

2 m

hB 2 m

2. Lp loc khong ong nhat loc kem hieu qua. Phan ln can gi lai lp cat tren (vai cm) TTAL qua lp

nay rat ln.

2 m

hC

C

B

A

cat sach

iem bao hoa(chat ban trong cat)



18/30

35

Visu

Ap suat(Cot ap, m)

Chieu cao, m

2 m

2 m

2 mhC hB

A

TTAL lp ay con thap.

t2

D

C

B

hD

t1


36

Visu

Ap lc(cot ap, m)

Chieu cao, m

2 m

2 mhB

A

3. TTAL qua ln vung co ap lc am/chan khong gia lp loc.(Ap lc < ap suat kh quyen)

2 m

4. Ap suat giam kh hoa tan trong nc tach ra hnh thanh tuikh giam dien tch loc hieu qua, tang van toc loc cuc bo TTAL tang, chat lng nc khong at yeu cau.

hChC

B

C

tui kh

5. Do hnh thanh ap lc am phan tren ngan VLLtac loc nhanh, lp ban

khong at ti ay be.

Ton That Ap Lc qua loc


19/30

37

Visu

Ton that ap lc hChieu cao e am bao cot ap yeucau

VL loc

Nc sach

au ong ra nen cao hn mot t so vi be mat lp loc tranhhut bot kh vao lp locBot kh hnh thanh tang nhanh TTAL giam chu ky locNeu lp ban tien ti ay loc gii han ve o uc en trckhi TTAL at gia tr max nen tang chieu day lp VLL e at t1= t2.

Thiet Ke Loc Nhanh

38

Visu

Thiet ke loc nhanh

Khac phuc Ap Lc Am:Dung lp loc ong nhat co hat ln hn;Loc hai/nhieu lp;Loc ap loc;Dong ra cao hn be mat lp cat

Loc ap lc

Green sand(lp ong

nhat)

Loc lp ong nhat

Dn phn phivo

Dan ong rabe mat

Dan ong thunc loc

vao

ra

Loc nhieu lp

AnthraciteSand

Granet

lp ra


20/30

39

Visu

h

Tieu chuan TK Loc Nhanh

TTAL (h):),U,e,L,f(h =

L = chieu day lp loc,e = o rong lp loc,U = Toc o loc, = o nht nc, = Khoi lng rieng cua nc,

TTAL la thong so quan trong:TTAL ban au: 0.5 - 0.8 mRa ngc khi TTAL: > 2.5 - 3.3 m

Phng trnh tnh toan TTAL qua lp VL loc:Carman-KozenyRose Equation.

40

Visu

Carman - Kozeny Equation

Ap dung PTrnh nay cho be loc khi o L = chieu day lp VLLva D = 4R, trong o R ban knh thuy lc dong i qua.Xet n v the tch VL loc, the tch dong i qua = o rong lploc (e)

g

U

D

Lfhl

2

2

..=

f = He so ma sat,L = Chieu dai ong,D = ng knh ong (ng knh thuy lc),U = Toc o trung bnh dong chay,g = gia toc trong trng

Suy ra t phng trnh Darcy ve TTAL trong ong tron:

L

hL

D

L

U


21/30

41

Visu


pVN.cantchtheTong =

N = so hat,VP = The tch moi hate = o rongAp = Dien tch be mat hat

)1(.

loclptchtheTonge

VN p

=

pVNee .

)1(quaidongtchthetong

=

pAN.matbetchdienTong =

p

p

A

V

ee

===

1matbetchDientchthe

tvichutchdienRTL,knhBan

42

Visu


Toc o vao loc i.e. (Face or approach velocity) toc o ch trenbe mat lp VLL.

6

d

A

V

P

P =

oi vi hat hnh cau co ng knh d:2dAP .=and

6

3dVP

.

=

Trong thc te cac hat VLL khong hnh cau ieu chnh banghe so hnh hoc .

6

d

A

V

P

P.=

tron canh = 0.98 sac canh = 0.70Cau = 1.00


22/30

43

Visu


veVS .=

Nh vay, toc o vao loc/toc o loc:

AQVS =

Khi dong chay vao lp loc, dien tch mat cat ngang giam (doVL loc chiem cho) toc o loc qua khe rong VL >> toc ovao locToc o vao loc:

v = T.o trung bnh qua loc

PT tren co the ap dung tnh toan TTAL qua loc hL khi lp loc chacac hat co ng knh riengf' He so ma sat.

=

g

V

e

e

d

Lfh SL

2

31

1..

.

Thay v va R:

44

Visu

Ra Ngc

be loc nhanh, can i xuong sau vao lp VL loc. tang TTAL en khi vt qua gii han TTAL cho phep tienhanh raLng nc ra: 5-10% lng nc loc

Rangc

Lc

Nc ra

Nc lcKh nn


23/30

45

Visu

Muc tieu ra ngc phai at 3 yeu cau sau :

Lp loc gian n: Lp cat phai gian len e can ban tach khoilp VL loc;Cac hat co xat nhau: Hat cat dc ra sach do lc keo va coxat gia cac hatGioi ra can ban: ay can ban len tren va xa ra ngoai.

o gian n at c oi hoi toc o nc ra nguc u ln.

Vao

Ra

Nc ra

Xa

o n (15-50%)

Loc Rangc

Ra Ngc

46

Visu

Phng phap ra ngc:a. Ra ngc ket hp ra be mat;b. Ra nc ket hp vi kh.

Loc ap lc(multimedia)

Vao

Ra

Loc Kh (option)

KhRa ngc

Xa

Ncra

Loc Trong lc Lc trng lc

Loc ap lc(multimedia)

Ra Ngc


24/30

47

Visu

Ra Ngc

La chon cach ra ngc:Kch thc VLL:Hat to toc o nc ra ln,Hnh dang VLL:Hat tron canh de ra sach hn.Mat o VLL:Lp VL co mat o hat cao hn can toc o ra loc ln hn e gian nlp loc.Chat lng nc:Nhieu SS hnh thanh vien bun dnh vao hat VLL kho raS dung CKT:hnh thanh lp mang bam vao be mat hat

48

Visu

Ra thuan tuy ncToc o nc u ln e lam gian n lp loc 15 - 50%.VL loc chuyen ong theo dong oi lu hnh thanh cac vungVL i len va i xuong.Khi lp tren mat co lp can bam day lp tren mat mangxuong di ay hnh thanh vien bun cng va to do dongxao tron.Khac phuc: ra be mat bang may ra cao ap e pha lp canbam be mat.Nhoc iem ra ngc thuan tuy nc: phan tang

o gian n

Loc Ra ngc


25/30

49

Visu

Ra Kh va Nc ong Thi

Toc o nc r ngc khong cao e tranh gian n lp loc

Sau o khuay tron lp loc bang thoi kh.Cat van gi on nh va lp can bam be mat b pha v vien bunkhong hnh thanh.

Thc hien theo cac bc sau :a. Ra ket hp kh va nc (khong lam gian lp loc).b. Xa bo nc ra:

Ra ngc bang nc+kh vi lu lng khong oi;Tang toc o ra ngc bang nc;

Nc tieu thu:

5 - 10% long nc san xuat.Khi ra ket hp kh va nc cothe giam khoang 20 -30% khi sosanh ra thuann tuy nc.

50

Visu

loai:Voi phun co nh;Voi phu quay.

Voi phun quay (Ap lc phun cao)Canh tay quay lap at tren lp loc;Voi phun phu nc thang goc vi be mat lp VLL.;.

Muc tieu:

Khuay tron cao tren be mat;Pha v cum bun.

Ra be mat

Ra be mat

Mang thu nc ra

Ra co nh Voi phun quay

Canh

tay quay

Water jets


26/30

51

Visu

Ra Nc va KhAp dung khi hat VL loc mn, VL co KL rieng thap nh than

anthracite hoac than hoat tnh.Thc hien theo 2 bc:a. Thoi kh e tach can ra khoi VL locb. Lu lng nc ra ngc ln gian n lp loc tach

can khoi lp VLL.Tan suat ra (F):

F = f (CL nc tho, TTAL, VL loc)

52

Visu

Cai Tien Loc Nhanh

Mt lp lc

Lc nhiu lp

Than

Anthracite

Lc hai lp

CtLp VL

Da trn vt liu lc:Lc mt lp: khng ha hn pht trin

Lc hai lp

Lc nhiu lp


27/30

53

Visu

Loc Hai LpLoc nhanh 1 lp phan tang xay ra trong QT ra ngckhong s dung hieu qua chieu day lp loc, TTAL caoKhac nhau kch thc, khac nhau ve t trong:Vat lieu cang nhe va cang tho lp yten (ex: anthracite r =1.35 to 1.7)Vat lieu nhe va mn ay (ex: cat r= 2.65 - 2.70)

Soi

Loc Nc ra

Kh nenXa loc au

Anthracite

Sand

vao

54

Visu

Loc hai lp

Thuan li Tang chu trnh loc len 2-3 lan so vi loc nhanh. Giam dien tch loc Tai trong uc cao Chu tai trong uc cao; De lap at, co the nang cao q5o; Do sap xep kch thc hat i t ln xuong nho theo chieu

dong chay hieu qua s dubg loc cao va s dung cong ch

Phan loaiDa tren dong chay Loc ngc; Loc hai dong.

Hng dong chay


28/30

55

Visu

Loc Ngc/tiep xuc

Muc tieu:

Hat phan bo t tho cho en mn theo chieu dong chay Nc vao t diKho khan: Phai tang toc o loc Khi TTAL cao co the ay lp loc l lng. Tranh ieu nay bang cach at lp li tren be mat cat.

Vo

Nc ra

Kh nn

X lc u

Nc lc

Ct

Si

56

Visu

Loc hai dong

e tranh gian n lp cat khi loc ngc a ap lc vaophan tren VL loc bang cach loc xuoi dong.Nc tho vao t nh va ay be loc, thu nc loc gia.

Vo

Nc lc

Nc ra

Kh

u ncra

Van x kh

Dn ng thu

1 lp 2 lp


29/30

57

Visu

Thi gian loc

Tocolo

c

Driving forceconstant

Loc ap lckhong oi

Mi quan h gia H v Q

Da tren toc o va ap suat co cac loai loc sau :Loc toc o khong oiLoc cot ap khong oiLoc toc o giam dan

ALoc ap lc khong

oi

Loc toc o giamdan

B

Loc toc o khongoiLoc toc okhong oi

Van ieu chnhlu lng

Cot aptruyen

58

Visu

Lc tc khngi:Hot ng thng thng ca b lc nhanh thng thng;Tn tht p lc l khng i;Tc lc khng i bng cch chnh valve kim sot lu lng;

Khi lc, lp lc dn dn b tt valve cng ngy cng m rng ra duytr tc lc khng i.

Bt li:

Cn h thng kim sot tinh vi;Cht lng nc ra khng tt.

Mi quan h gia H v Q


30/30

59

Visu

Lc p sut khngi:

Tng gim p l khng i trong sut chu trnh lc;u chu k lc, lu lng nc qua lc ln tiu hao lng lnnc x lc u

Khi b lc bt u ngt dn n gim tc lc;Cn d tr lng nc ra ln.

Lc c tc gim dn:

C p lc khng i v lu lng khng i;

Khng c h thng kim sot lu lng;Tc lc cho php gim t gi tr ln nht u chu k lc (ct sch)v nh nht cui chu k khi b lc cn ra ngc.

Mc nc trn lp ct lc tng cui chu k lc v t gi tr gii hncho php.

Mi quan h gia H v Q

Chapter5 Loc

Documents