Nghiên cứu khả năng xử lý nước thải chế biến mắm châu đốc bằng công nghệ oxi hóa nâng cao ozone UV

..

TRtfONG BAI HOC AN GIANG
KHOA KY THU^T - CONG NGHI^ - MOI TRtfONG

HO VAN THANG

NGHIEN CUtJ KHA NANG X& LY Nl/6C THAI
CHE BIEN MAM CHAU DOC BANG CONG
NGHE OXIHOA NANG CAO (OZONE + UV)
TRU^NG B^lHQC
AN GIANG

THlJVIEN
KHOA LUAN TOT NGHIEP

GVHD: Th.S Truong Kien Tho

An Giang, 05/2013


LOI CAM ON
is.Ga.es-

Trong khoang thai gian hoc tap tai Truang Dai Hoc An Giang, toi da
dugc quy Thay co tan tinh hudng dan, giang day tvr nhung mon hoc dai cuang,
chuyen nganh den nhttng ky nang, dao diic trong cuoc song. Dae biet trong
suot qua trinh thuc hien de tai khoa luan tot nghiep ciia minh la Ian dau tien co
ca hoi tiep can cong viec nghien curu khoa hoc nen con gap khong it kho khan,
nhung dugc su dong vien giup da nhiet tinh cua quy Thay co, gia dinh va ban
be da giup toi hoan thanh khoa lu^n tot nghiep nay. Trong khoang thai gian

nay giup toi nang cao dugc kien thiic chuyen mon, tong ket dugc nhung kinh
nghiem thuc tiSn trong Bnh vuc moi truong. Day se la nhung kien thiic b6 ich,
la hanh trang quy gia cho cong viec cua toi trong tuang lai. Thong qua bai bao
cao khoa luan tot nghiep nay, toi xin chan thanh cam an den:
Ban giam hieu Nha Truang, Khoa Ky thuat - Cong nghe - M6i truang,
quy Thiy co trong Bo mon Moi truang va Phat triSn b^n vung da trang bi ki^n
thuc cho toi trong suot qua trinh hpc tap.
Thay Truang Kien Thp da tan tinh hudng dan va dong gop nhung y kien
quy bau cho toi trong suot qua trinh thuc hien de tai khoa luan tot nghiep.
Thay NguySn Trung Thanh, co Nguyln H6ng Nhat can bo phu trach
phong thi nghiem Khoa Ky thuat - Cong nghe - Moi truang da cung cap tai
lieu va giup da toi trong qua trinh thi nghiem.
Ngoai ra toi xin gui lai cam an den tat ca nhung nguai ban cua toi,
nhung nguai da gan bo, cung hoc tap va giup d9 chung toi trong nhung nam
qua cung nhu trong suot qua trinh thuc hien de tai khoa luan tot nghiep.
Mac du da co nhieu co g^ng, no luc nhung vai kiSn thuc va thai gian
nghien cuu con h^n che nen noi dung d^ tai khong thi tranh nhung thilu sot.
Rat mong nhan dugc su gop y cua quy Thly co.
Toi xin chan thanh cam an!
Long Xuyen, ngay 2 thang 5 nam 2013
Sinh vien thuc hien

H6 Van Thing


NHAN XET CUA GIANG VIEN HtfONG DAN

Long Xuyen, ngay 17 thang 5 nam 2013

Th.S Truong Kiln Tho

NHN XET CUA GIANG VIEN PHAN BIENI

Long Xuyen, ngay 17 thang 5 nam 2013

TS. Nguyln Trung Thanh


NHAN XET CUA GIANG VIEN PHAN BIEN II

Long Xuyen, ngay 17 thang 5 nam 2013

Th.S Truong Khanh Nhat Thao


Kltda luqn tdt nghepLop DH10MT

MUC LUC
CHUONG I: GIO1THIEU1
CHUONG II: LUOC KHAO TAI LIEU3
2.1. Tong quan v6 nude thai ch bi&i mim Chau D6c3
2.1.1. Vdinetve che Men mam ChduDdc3
'2.1.2. Ngudn goc phdt sinh nude thai che biin mam.•4

2.1.3. Phuongphdp xic ly nude thai che Men mam Men nay4
2.3.Tong quan ve phuong phap oxihoanang cao5
2.3.1.Nhung hqn che cua qua trinh oxi hda hda hoc bang ede tdc nhdn
oxihoa thong thudng5
2.3.2.Nhung uu viet cua qua trinh phdn huy oxi hda bang goc tu do

hydroxyl (*OH)6
2.3.3.Cdc qua trinh tqo ra goc hydroxyl (*OH)9
2.3.4.Phdn loqi cdc qua trinh oxi hda ndng cao10
2.4.Mot so qua trinh oxi hoa nang cao da duoc nghien ciiu12
2.4.1.Qua trinh oxi hda ndng cao khdng nhd tdc nhdn dnh sang12
2.4.2.Qua trinh oxi hda ndng cao nhd tdc nhdn dnh sang14

CHUONG ni: NOI DUNG VA PHUONG PHAP NGHIEN CUU18
3.1.Boi tuong nghien cuu18
3.2.Thai gian nghien ciiu18
3.3.Muctieu nghien cuu.....18
3.3.1.Muc tieu chung18
3.3.2.Muc tieu cu thh18

3.4.Npi dung nghien cuu19
3.5.Phuang tien va vat lieu nghien cuu19
3.6.Phuang phap nghien ciiu19
3.6.1. Phuong phdp phdn tich cdc thong so 6 nhiem19

GVHD: ThS. TruongKiin TitoTrang i

SVTH: Hd Van Thang


Khoa lu&n tit nghepLop DH10MT

3.6.2.Phucrngphdp xic ly so lieu22
3.6.3.B6trimo hlnh22

3.7. Thai gian hru trong 6ng24

CHlTONG IV: KET QUA THAO LUAN25
4.1.Ket qua do cac chi tieu ciia mau nude thai theo thai gian26
4.1.1.Kit qua do cac chi tieu ciia mo hlnh sic dung ozone :26
4.1.2.Kit qua do cac chi tieu cua mo hlnh sic dung ozone vd UV31

4.2.Ket qua do cac chi tieu cua mau nude thai theo he so pha loang36
4.2.1.Kit qua do cac chi tieu cua mo hlnh sic dung ozone36

4.2.2.Kit qua do cac chi tieu cua mo hlnh sic dung ozone va UV41

CHUONG V: KET LUAN VA KIEN NGHI48
5.1.K6tluan48
5.2. Kiln nghi49

TAI LIEU THAM KHAO50

GVHD: ThS. Truong Klin ThpTrangii

SVTH: Hd Van Thdng


Kitoa luan tit ngh^pLop DH10MT

DANHSACHHINH
Hinh 2.1: Quy trinh ch bidn mint3
Hinh 3.1: Su dung ozone d xu: ly nude thai che bien mini23
BQnh 3.2: Sil dung ozone kit hop vdi den UV de xu.Iy nude thai che bien
mam23

Hinh 4.1: Bidu dd bieu diln su thay d6i pH theo thai gian cua mo hinh su
dung ozone25
•H inh 4.2: Bilu dd bilu didn su thay ddi SS theo thdi gian cua mo hinh su
dung ozone26
Hinh 4.3: Bilu dd bieu diln su thay ddi COD theo thdi gian cua mo hinh su
dung ozone27
Hinh 4.4: Bilu dd bilu dien su thay ddi NH4+ theo thdi gian cua mo hinh su
dung ozone28
Hinh 4.5: Mo hinh xu ly nude thai chS bifin mim b^ng qua trinh ozone29
Hinh 4.6: Mo hinh xu ly nude thai che bien mam bang qua trinh ozone dang
hoatdpng29
Hinh 4.7: Mau thu dugc sau khi sue khi ozone trong thdi gian 240 phut30
Hinh 4.8: BiSu dd bieu diln su thay ddi pH theo thdi gian cua mo hinh su
dung ozone va UV31
Hinh 4.9: BiSu dd bieu diln su thay ddi SS theo thdi gian cua md hinh su
dung ozone va UV32
Hinh 4.10: Bidu dd bieu diln su thay ddi COD theo thdi gian cua md hinh su
dung ozone va UV33
Hinh 4.11: Bieu dd bieu dien sir thay ddi NH4+ theo thdi gian cua md hinh su
dung ozone vaUV'.34

Hinh 4.12: Md hinh xd ly nude thai che bien m^m bang qua trinh ozone va
UVr35
Hinh 4.13: Mau thu dugc sau khi sue khi ozone va UV trong thdi gian 240

phut35

GVHD: ThS. Truong Kien TlwTrang Hi

SVTH: Hd Van Thing

Khoa limn tdt nghepL&p DH10MT

Hinh 4.14: Bieu do bieu dien su thay doi pH theo he so pha loang cua mo
hinh su dung ozone36
Hinh 4.15: Bieu do bieu dien su thay doi SS theo he so pha loang cua mo hinh
su dung ozone37
Hinh 4.16: Bieu do bieu dien su thay doi COD theo he so pha loang cua mo
hinh sur dung ozone38
Hinh 4.17: Bilu d6 bilu diln su thay dli NH4+ theo he s6 pha loang cua mo
hinh su dung ozone40
Hinh 4.18: Mau thu dugc sau khi sue khi ozone trong thai gian 240 phut theo

he s6 pha loang41
Hinh 4.19: Bieu do bieu dien su thay doi pH theo he so pha loang cua mo
hinh sudung ozone vaUV42

Hinh 4.20: Bilu d6 bilu diin su thay d6i SS theo he s6 pha loang cua mo hinh
su dung ozone vaUV43
Hinh 4.21: Bieu d6 bilu diln su thay d6i COD theo he s6 pha loang cua mo
hinh su dung ozone va UV44
Hinh 4.22: Bilu d6 bilu diln su thay d6i NH4+ theo he s6 pha loang cua mo
hinh su dung ozone va UV46
Hinh 4.23: Mau thu dugc sau khi sue khi ozone va UV trong thai gian 240
phut theo he so pha loang47

GVHD: ThS. Truong Kim ThpTrmig iv

SVTH: Ho Van Thing

Klwa luan tdt nghepL&p DH10MT

DANH SACH BANG
Bang 2.1: Kha nang oxi hoa cua mot so tac nhan oxi hoa6

Bang 2.2: Cac hop chit hilu ca bi oxi hoa boi g6c hydroxyl (*OH) da dugc
nghienciiu9
Bang 2.4: Cdc qua trinh oxi hoa nang cao khong nha tac nhan anh sang10
Bang 2.5: Cac qua trinh oxi hoa nang cao nhd tac nhan anh sang11
Bang 2.6: D^c trung pho bile xa dien tu cua anh sang14
Bang 3.1: Ti&i dp thirc hien &b tai18
Bang 4.1: K6t qua do cac chi tieu cua mlu nuac thai dau vao25
Bang 4.2: KSt qua do pH sau khi sue khi ozone theo thai gian25
Bang 4.3: Ket qua do SS sau khi sue khi ozone theo thai gian26
Bang 4.4: KSt qua do COD sau khi sue khi ozone theo thai gian27
Bang 4.5: Ket qua do NH/ sau khi sue khi ozone theo thai gian28
Bang 4.6: K8t qua do pH sau khi sue khi ozone vaUV theo thai gian31
Bang 4.7: Ket qua do SS sau khi sue khi ozone va UV theo thai gian32
Bang 4.8: Ket qua do COD sau khi sue khi ozone theo thai gian33
Bang 4.9: KSt qua do NH4+ sau khi sue khi ozone va UV theo thai gian34
Bang 4.10: Ket qua do pH sau khi sue khi ozone theo he so pha loang36
Bang 4.11: Ket qua do SS sau khi sue khi ozone theo he so pha loang37
Bang 4.12: Ket qua do COD sau khi sue khi ozone theo he so pha loang38
Bang 4.13: Ket qua do NH,^ sau khi sue khi ozone theo he s6 pha loang....... 39

Bang 4.14: Ket qua do pH sau khi sue khi ozone va UV theo he s6 pha loang

41

Bang 4.15: Ket qua do SS sau khi sue khi ozone va UV theo he s6 pha loang

42
Bang 4.16: Ket qua do COD sau khi sue khi ozone va UV theo he so pha
loang44
Bang 4.17: Ket qua do NH4+ sau khi sue khi ozone va UV theo he so pha
loang45

GVHD: ThS. Truomg KiSn TitoTrang v
SVTH-. mVatiTMng


Khoa liian tdt nghepLop DH10MT

DANH SACH TU* VIET TAT

V: Volt

SS: Chit r8n la lung
UV: Tia cue tlm
NT: Nuac thai
COD: Nhu ciu oxy hoa hpc
TOC: Tong cacbon hitu ca
AOPs: Qua trinh oxi hoa nang cao
USEPA: Co quan bao ve moi trubng My ^

GVHD: ThS. Tmong Kiin ThpTrangvi
SVTH: H6 Van Thang

Khda liian tdt nghep"L&pDHlOMT

NGHIEN CtfU KHA NANG XLf LY NUOC THAI CHE BIEN MAM
CHAU DOC BANG CONG NGHE OXIHOA NANG CAO
(HE OZONE + TIA UV)
Tom tdt:
Cho den nay cong nghe xd ly nude thai che bien mam Chau Doc van
dang la van de khd khan bdi thanh phan nude thai chiia ham lucmg hftu ca
cao, kho phan huy. KSt qua khao sat tren nude thai ch^ bien mim sau xu ly da
xac dinh thanh phSn nude thai con chua mot luqng dang kg cac hcrp chat huu
co vdi COD cao.
Qua trinh oxi hda nang cao da duoc nghien cuu va ap dung thanh cong
trong ltnh vuc xu ly nude va nude thai.
De tai nay nghien cdu kha nang xu ly cua he ozone + tia cue tim de danh
gia hieu qua xu ly nude thai cbi bien m^m.
Ket qua nghien cuu cho thay, xu ly nude thai che bien mam bang cong
nghe oxi hda nang cao da chiing minh he ozone + tia cue tim xu ly hieu qua
hon so vdi he ozone vdi hieu suSt xu ly SS, COD, NH4+ cao han tCr 1.4 —
9.8%. Ap dung chay mo hinh O3AJV vdi ham lucmg O3 la 4g/h, cong suSt den
UV la 30W thl hieu qua xii ly COD cd thg dat 50.9% trong 240 phut va 67.1%
trong 240 phut theo he s6 pha loang. Nghieu cdu con cho thay sir thay doi pH
trong qua trinh xu ly.

GVHD: ThS. TmerngKiSn ThgTrangvii

SVTH: Hb Van Thdng


Klwa hian tdt nghepL&p DH1OMT

RESEARCH CAPACITY PROCESSING WASTE WATER
TREATMENT SALTED FISH CHAU DOC BY OXIDIZE ADVANCED
TECHNOLOGY (THE UV + OZONE SYSTEM)

Abstract:
Up to now, processing wastewater treatment technology Chau Doc salted
fish being a difficult problem. Because the wastewater composition contains
high organic content, hard disintegration. Result investigated wastewater
processing salted fish after treatment were defined wastewater composition
still contains significant amounts of organic compounds with high COD.
Advanced oxidation process has been studies and successful applied in
the field of waste treatment and wastewater treatment.

This subject studies treatment capable of ozone + UV to evaluate the
effectivenessof wastewater treatment processing salted fish.

The reseach results showed that wastewater treatment processing salted
fish using technology advanced oxidative to proved ozone + UV treatment
more effective than ozone with efficency treatment of SS, COD, NH^ high
more from 1.4% to 9.8%. Apply O3/UV model run with O3 concentration is
4g/h, UV lamp power is 30W, then the efficiency treatment of COD can reach
50.9% in 240 minutes and 9701% in 240 minutes by the dilution factor.
Studies have also showed that the pH change in the treatment process.

GVHD: ThS. Trircmg Kien ThpTrang viii

SVTH: H6 Van Thing


Klwa luan tSt nghepLopDHlOMT

CHl/ONG I: GIO1THIEU

M&m la nghd san xuat lau ddi a Dong bang song Cuu Long cua Viet
Nam va mot so nude D6ng Nam A nhu Lao, Campuchia, Thai Lan, Malaysia,
Myanmar, Indonesia va Philippines. Vi co cung cac dieu kien thuan lpi cua tu
nhien. Rieng a Thai Lan ngudita nhan thay co 16 loai mam khac nhau. (3 cac
quoc gia khac ngudi ta nhan thay ring chiing tuong tu cac loai mam d Thai
Lan vd ban chat. Tuy nhien, chung co the xuat hien vdi cac hinh thiic trinh bay
san phim khac nhau, tuy thudc vao didu kien song, phong tuc tap quan cua cac
dan toe (Adam, Cook et Rattagool, 1985).
Mam duqc lam tu ngudn thuy san nude ngpt la mdn an co gia tri cua
ngudi dan mien Tay Nam Bo ndi chung va cua vimg Chau Doc - An Giang
ndi rieng.
MSm Chau Doc khdng chi la mdn an co truyen ndi tieng cua ngudi dan
dia phuong ma con la mdn an pho bidn va duoc xudt khau sang nhieu nude
tren thd gidi nhim phuc vu cho ddng bao Viet Nam d xa to quoc.
Ben canh do, san xuat mim la mot trong so cac nganh co nguy co gay d
nhilm nghiem trong ddn mdi trudng bdi thanh phan nude thai che bien mam
chua mpt lupng dang kd cac hop chit huu co khd phan huy nhu: mo, mudi,....
Nen nude thai che bien mam khdng the xu ly triet de bang cac cdng nghe
truyen thong.

Trudc nhQng yeu cau va thach thuc ngay cang cao ciia nganh xu ly nude
thai, cac nha khoa hoc va cdng nghe da tien hanh nhidu cdng trinh nghien cuu
theo hudng tim cac cdng nghe cao de hd trp cac cdng nghe xu ly truydn thong.
Cac cdng nghe cao thudng gap nhu: cdng nghe lpc bang mang, cdng nghe khu
trung nude bang buc xa tu ngoai, cdng nghe phan huy khoang hda chat d
nhiem huu co bang qua trinh oxi hda nang cao.
Trong so nhtrng cdng nghe do, cdng nghe dua vao qua trinh oxi hda nang

cao la cdng nghe dupe nghien cuu va ung dung nhieu nhat trong thai gian gan
day.

Vao nam 1987 Gurol va Vatistas da so sanh hieu cua cac qua trinh oxi
hda nang cao: UV, O3, UV/O3 cho xu If cac hop chit phenol. Kdt qua nghidu
cuu da chung minh kha nang khd TOC trong he UV/O3 la cao hon hln.

GVHD: ThS. Tmffng Kiin ThoTrang 1

SVTH: Hd Vein Tilting


Khoa hum tit nghepLefp DH10MT

Nghien eta khac cua Stowell et at. (1990) cung da xac dinh he UV/O3 co
kha nang gia tang toe dp oxi hoa acid chlorendic. Trong do, cac ygu to nhu
pH, su hien dien cua ion carbonat va cuong dp anh sang se anh huong dang ke
d6n qua trinh hinh thanh g6c hydroxyl hoat tinh.
Lai et al. (1995) da nghien cuu oxi hoa simazin trong nuoc thai tu tao
bang qua trinh UV/O3. Nong dp ban dau cua simazin: 4 mg/1. Thai gian ltru
trong thiSt bi phan tag: 15 phut. Su oxi hoa xay ra hoan toan khi str dung O3
vai luang 34 mg/phut va pH = 7,2.
Tir nhtag uu viet tren, chung toi thuc hien &h tai: "Nghien cuu kha
nang x& ly nu&c thai die Men mam Ch&u Doc bang cdng nghi oxi hoa
nang cao (Ozone + UV)" de gop phan khac phuc cac van de 6 nhiem tir nuac
thai che bien mam.

GVHD: ThS. Truong Kien ThpTrang 2

SVTH: Hd Van Thing

Kit6a luan tdt nghSp

LdpDHlOMT

CHUONG II: LtTGC KHAO TAI LIEU

2.1. T6ng quan vl nirox thai ch biSn ra^m Chau B6c
2.1.1. Vai net v6 ch^biln mam Chau D6c
•4 Nguyen lieu: che biln mim chu yeu tCr nguon thuy san nuac ngpt
nhu: Ca 16c, ca linh, ca chot, ca thieu,...

4 So lupt ve quy trinh che Men mam

Xiily
Rua, cte rao

Muoi ca

Dung cu chua

Gai nen

Rua, de rao

X
Tron thinh

Vao lu, gai nen

X
Bao quan cha chin

X
Chao duo^ig

Hinh 2.1: Quy trinh che Men mam
GVHD: TliS. Trwffng Kien Tho

SVTH: Hd Van Thing

Trang3


KItda luan tdt nghepLop DH1OMT

2.1.2.Nguon goc phat sinh nude thai che bien mam

Nude thai che bien mim gdm co: Nude san xuat, nude thai ve sinh cong
nghiep va nuac thai sinh hoat.
>Nuac th^i san xuit la loai nude dugc dung di rua nguyen lieu trong
day chuyen che bien mam.

>Nude thai ve sinh cong nghiep la loai nude dung de ve sinh cho
cong nhan trudc va sau khi vao lam viec, nude diing de rua dung cu che bien,
thiet bi, may mdc va san nha mi ngay.
^Nude thai sinh hoat ciia can bp, cong nhan vien trong cac ca sd.
Day cung la lupng nude thai dang ki vi trong ca sd che bien mam cd so lupng
cong nhan kha dong, do do nhu ciu su dung nude cho cac hoat dong sinh hoat

la rlt cao.

2.1.3.Phuoug phap xit ly nude thai chl bien mam hien nay
Hien nay, ngudi ta van ap dung phuang phap truyen thong (phuang phap
ca hoc) d^ xii ly nude thai ch6 bien mim:
Phuang phap ca hoc: nham loai bo khdi nude thai cac chdt phan tan tho,
cac chat vo ca (cat, san, sdi...), cac chat la lung cd the lang dupe bang each
lang va lpc..., va dupe thuc hien qua cac cong trinh dan vi tuong ung nhu:

song chin rac (hoac ludi lpc rac), b^ ling cat, be tach diu ma va cac chat ndi
khac, be diiu hda, b lam thoang so bp, be ling, bi lpc.
Trong rat nhieu trudng hpp, phuang phap thong thudng ke tren khong
dat hieu qua cao. Vdi cac loai nude thai nhiem cac chat doc kho phan huy,
chang han thuoc trir sau, thuoc diet cd, con, det nhupm ..., vi sinh vat hau nhu

khong hoat dong dupe, do vay ap dung phuang phap vi sinh to ra rat it hieu
qua. De.giai quyit van de nay, ngudi ta da ap dung cac phuang phap oxi hda
nang cao (Advanced Oxidation Processes-AOPs).
2.3. Tong quan ve phuang phap oxi hda nang cao
Mot trong nhung cong nghe cao noi len gan day la cong nghe phan huy
khoang hda chat 6 nhiem huu ca trong nude va nude thai dua vao qua trinh
oxi hda nang cao. Qua trinh oxi hda nang cao dupe dinh nghla la nhung qua
, trinh phan huy oxi hda dua vao gdc tu do hoat dong hydroxyl (*OH) dupe tao
ra ngay trong qua trinh xu ly. Gdc hydroxyl la tac nhan oxi hda manh nhit
trong sd cac tac nhan oxi hda dupe biet tu trudc den nay, cd kha nang phan
GVHD: ThS. Truffng Kiin ThoTrang 4
SVTH: Ho Van ThSngx


Khoa luan tdt nghepLopDHlOMT

My oxi hoa moi hgp chat huu ca, du la loai khd phan huy nhat, chuyen hoa
chiing thanh cac hop chat vo ca khdng doc Mi nhvr CO2, H2O, cac axit vo ca.
Tir nhung tac nhan oxi hoa thong thuong nhu hydrogen peroxit, ozone.. .co the

nang cao kha nang oxi hoa cua chung bang cac phan ting hoa hoc khac nhau
de tao ra cac goc hydroxyl, thuc hien qua trinh oxi hoa gian tiep thong qua goc
hydroxyl.
Cac qua trinh oxi hoa nang cao da n6i len trong nhung nam gan day nhu
mot loai cdng nghe cao co tarn quan trong trong viec day manh qua trinh oxi
hoa, giiip phan My nhieu loai chat huu ca 6 nhiem khac nhau trong nude, dac
biet la cac chat 6 nhiem huu ca kho phan huy.
Gin day, cac qua trinh oxi hoa nang cao dugc nghien cuu nhieu va ling
dung rat nhieu trong lihh vuc xu ly nude thai.
2.3.1. Nhfl'ng han che cua qua trinh oxi hoa hoa hoc bang cac tac

nhan oxi hoa thong thuxmg

a)Khi Clo (Cl2)
Clo la chit oxi hoa hoa hoc tdt dugc sii dung dd khii Fe2+ trong nude
ngam hoac nude mat, trong khu trung nude sau khi xii ly. Vi cio la chat oxi
hoa manh, re tidn va de sii dung nen dugc su dung phd bien trong llnh vuc xii
ly nude, nude thai cho din ngay nay. Tuy vay nhugc didm cua clo la tac dung
vdi chat huu ca thien nhien, tao ra hop chat huu ca chiia clo co nguy ca gay
ung thu cho ngudi sii dung (Fran Manh Tri— Trdn Manh Trung, 2006).
b)Kali permanganat (KMnO^)
Kali permanganate la chat oxi hoa dugc sii dung rpng rai trong xu ly
nude. Day la chat oxi hoa manh han clo, co the lam viec trong khoan pH rpng,
nhung dat tien. Them vao do, qua trinh hay tao ra mangan dioxit d dang khong
tan va phai tach ra bang phuang phap hoa hoc hoac lang; vi vay kha nang tang

them chi phi cho qua trinh xu ly la didu khong thl tranh khoi.
c)Hydrogen peroxit (H2O2)
Hydrogen peroxit la chat oxi hoa manh han clo va kali permanganat
nhung yeu han ozone (O3) va dugc sii dung rat phd bien trong xii ly nude thai
de phan My cac chat huu ca va khu mau cua nude thai nganh giay hoac det
nhupm. Ngoai ra, uu diem cua hydrozen peroxit la khong sinh ra chit doc
hoac chat co mau trong qua trinh sii dung. Tuy nhien, kha nang oxi hoa ciia
hydrozen oxit khong dii manh de khoang hoa Man toan chit d nhidm huu ca
nhu yeu ciu da dat ra (Trin Manh Tri- Trdn Manh Trung, 2006).
GVHD: ThS. Truong KiSn TlwTrang 5

SVTH: Hd Van Thing


Khoa hum tdt ngltepLop DH10MT

d) Ozone (O3)
Ozone la chit oxi hda manh hern so vdi cac chat oxi hda thong dung ke
tren. No dugc sii dung lam chat khu trung, phan huy cac chat him co hoac de
khu mau nude thai, khu miii hoi, khu sit hoac mangan,... uu diem cua

mangan la tu phan My, khong dl lai cac phu pham la va nguy hiem trong
nude sau khi phan ring. Tuy vay, ozone kem hoa tan trong nude va la hop chat
khong bin, thai gian tin tai chi vai phut. Vi vay de dat duac so luang ozone
hoa tan trong nude dii ldn cho qua trinh oxi hoa, phai dua vao he mot so lupng
ozone ldn. Ngoai nhugc dilm tren, khi su dung ozone lam chat oxi hoa trong
xu 11 nude va nude thai la phai san xuat ozone tai cho, ngay trong day chuyen
xiily.

2.3.2. Nhu-ng uti viet cua qua trinh phan huy oxi hoa bing goc tu1 do

hydroxyl (*OH)
a) G6c hydroxyl (*OH) va kha nang oxi hoa cua goc hydroxyl
Oxi hoa la qua trinh trong do electron dugc chuy^n tir chat nay sang chat
khac. Di^u nay tao cho ra mot the dien cue dugc bieu thi bing volt (V) du tren
hieu the dien cue hydrogen bang 0. Moi chat (tac nhan) oxi hoa deu cd mot the
oxi hoa khac nhau va dai lugng nay dung de danh gia tinh oxi hoa manh hay
yeu khac nhau cua chung. Kha nang oxi hoa dugc the hien qua the oxi hoa va
dugc sap xep theo thii tu trong bang 2.1.
Bang 2.1: Kha nang oxi hoa cua mot so tac nhan oxi hda

Tac nhan oxi hda

The oxi hda (V)

Goc hydroxyl

2,80

Ozone

2,07

Hydrogen peroxit

1,78

Permanganat

1,68

Hydrobromic axit

1,59

Clo dioxit

1,57

Hypocloric axit

1,49

Hypoiodic acid

1,45

GVHD: ThS. Truffng Kiin ThpTrang 6
SVTH: H6 Van Thdng


Khoa lunn tdt nghepL&pDHlOMT

Clo1,36
Brom1,09
Iod0,54
(Ngudn: Tr&n Manh Tri- Trdn Manh Trung, 2006)
Trorig cac tac nhan oxi hoa tren, g6c tu do hyroxyl (*OH) la tac nhan oxi
hoa manh nhat. Qua bang 2.4 ta thay, the oxi hoa goc hydroxyl la 2;8 V, cao
nhat trong so cac tac nhan oxi hoa thuang gap, gap 2,05 Ian clo va 1,52 Ian

ozone.

Bac tinh cua g6c tir do la trung hoa v6 dien trong khi cac ion dieu
mang dien tich duong hoac am. Goc tu do dugc tao thanh tir sir tach ra hai
phan bang nhau cua lien ket hai electron, vi du: khi quang phan H2O2 se thu
duqc 2 goc *OH nhu sau:
HO:OH + hv - *OH + *OH
M6i g6c *OH d6u khong mang dien, hai g6c *OH co the kt hop trd
lai thanh HOOH cung khong mang dien. (Luu y: ky hi6u* cho biSt la goc tir
do va bieu thi mot electron le doi). Goc tir do nay khong ton tai san trong moi
tnrong nhu nhung tac nhan oxi hoa thong thuong, ma chi san sinh ra ngay
trong qua trinh phan ling, co thai gian song rat ngan, khoang vai nghin giay
nhung lien tuc dugc sinh ra trong su6t qua trinh phan tog (Tran Manh Tri Trdn Mgnh Trung, 2006).
b) Co' che phan ung va phuong thiic phan irng cua goc hydroxyl
OH*
Mt khi goc tu do dugc hinh thanh, lap tiic xay ra hang loat cac phan tag
ke tiep theo kieu day chuyen vdi nhung goc hoat dpng mdi. VI vay, sir hinh
thanh g6c hydroxyl dugc xem nhu la mot sir khai mao cho hang loat cac phan
tog xay ra ke tiep trong dung dich. Vi phan tog cua g6c hydroxyl xay ra
khong chpn lira, nen trong qua trinh do tao ra nhieu san pham trung gian khac
nhau, kho tien don tat ca nhtog san pham oxi hoa trung gian co thl tao ra
trong qua trinh.

Goc hydroxyl (*OH) co thl tac kich vdi cac chdt 6 nhilm theo cac kilu
sau:

GVHD: ThS. Truong Kiin ThoTrang 7

SVTH: H6 Van Thdng

Khoa luan tdl nghepL&pDHlOMT

-Phan mig cong vdi cac hap chit khong no day thang hoac vong thorn,
tao ra goc mdi hydroxylat hoat dpng:
*OH + CH2 = CH2 -> *CH2-CH2(OH)
-Phan ling tach hydrogen tir cac hop chat no hoac khong no, tao thanh
nude va goc mdi hoat dpng:
*OH + CH3 - CO - CH3 - *CH2COCH3 + H2O
- Phan ling trao dien ttr tao ra g6c ion mdi hoat dpng:
*OH + CH3-S-C6H5 -^ [CH3-S-C6H5]+*+ OH"

Qua trinh phan ling tiep tuc phat triin nhd cac gdc tir do mdi sinh ra theo
kieu phan ling day chuyen cho den khi vo co hda (khoang hoa) hoan toan hoac
day chuyen bi diit.'
Muc dich mong muon cuoi cung trong qua trinh oxi hda cac chit 6 nhiem
trong nude thai la di vo co hda, tiic chyin chit 6 nhidm him co thanh cac chat
vo co don gian va khong doc hai. Cu the la:
-Carbon trong phan tir chit 6 nhilm thanh carbon dioxide.
-Hydrogen trong phan hi chat 6 nhilm thanh nude.
-Phospho trong phan hi chat 6 nhiem thanh phosphate hay acid
phosphoric.
-Sulfur trong phan hi chat 6 nhiem thanh sulfate.
-Nitrogen trong phan tu chat 6 nhilm thanh nitrate.
-Halogen trong phan hi chat 6 nhilm thanh acid halogenic.
-Cac hop chat vo co tao thanh trang thai oxi hda cao hon nhu Fe2+ thanh
Fe3+.

Dae diem chung cua qua trinh oxi hda bdi cac tac nhan thong thudng la
khong the xay ra vdi moi chat va khong the xay ra triet de. Trong khi do, goc

*OH thi nguoc lai.

GVHD: ThS. Truong Kien ThoTrang 8

SVTH: Hd Van TMng


Khoa luan tot nghep

Ldp DH10MT

Bang 2.2: Cdc hap chat him ca bi oxi hoa bai goc hydroxyl (*0H) da
duac nghien cim.

STT

Hop chSt

Nhom

Axit

Fomic, gluconic,lactic, malic,propionic, tactaric

Benzyl, tert-butyl, etanol, etylen, glycol, glyxerol,

Alcohol

Aldehyd

iso-propanol,methanol, propenediol

Axetaldehyl, benzaldehyd, focmaldehyl, glyoxal,
iso-butyraldehyd, tricloroaxetaldehyd.

Benzen, clorobenzen, clorophenol, creozot,

Aromatic

diclorophenol, hydroquinon, p-nitrophenol, phenol,
toluen, triclorophenol,xylem, trinitrotoluene.

Amin

Thudc

Anilin, amin vong, dietylamin, dimetylfocmamid,
EDTA, propandiamin, n-propylamin

Antraquinon, diazo,monoazo

nhuom
Eter
Keton

Tetrahydrofuran
Dihydroxyaxeton, metyl-etyl-keton

(Ngudn: Trdn Manh Tri- Trdn Manh Trung, 2006)
2.3.3. Cac qua trinh tao ra goc hydroxyl (*OH)

Do goc hydroxyl OH* co kha nang oxi hoa rat manh, t6c dp phan ling oxi
hoa rat nhanh va khong chpn lira khi phan ling voi cac hop chat khac nhau,
nhieu cong trinh nghien cuu trong nhieu nam qua la tim kiem cac tao ra goc
OH* tren ca sa cac tac nhan oxi hoa thdng thuang nhu hydrogen peroxide
thong qua phan ling hoa hoc (H2O2/Fe2+, O3/H2O2, O3/xuc tac), hay nha nang
luang hire xa tia UV (O3/UV, H2O2/UV, O3+H2O2AJV, TiO2/UV) va cac
nguon nang lupng cao (sieu am, tia gamma, tia X, chum electron).

GVHD: ThS. Truong Kien Tho

SVTH: Hd Van Thdng

Trang 9


Khoa limn lit nghep

L&pDHlOMT

2.3.4. Phan loai cac qua trinh oxi hda nang cao

Theo co quan bao ve moi truong My (USEPA), dira theo dac tinh cua
qua trinh co hay khong co sii dung nguon nang lugng biic xa tu ngoai UV ma
co the phan loai cac qua trinh oxi hoa nang cao thanh hai nhom:
> Cac qua trinh oxi hoa nang cao khong nho tdc nhdn dnh sang
Cac qua trinh oxi hoa nang cao khong nho tac nhan anh sang la cac qua
trinh khong nho nang lugng buc xa tia cue tim UV trong qua trinh phan ung
va chiing dugc liet ke 6 bang 2.3.
Bang 2.4: Cac qua trinh oxi hoa nang cao khong nho tac nhan anh sang
TT

Tac nhan phan

Phan ung dac trung

Ten qua trinh

ung
H202vaFe2

2+-> Fe3+ + OH"+Fenton

*HO
2H202va03H2O2 + 2O3-> 2*HO + 3O2Peroxon
3O3 va cac chit xuc3O3 + H2O —^!-• 2*HO +Catazon

tac4O2
4H2O va nang lugngH2O

"* > *HO + *HOxi hoa dien

dien hoahoa
5H2Ova nang lugngH2O
sieuam

""" > *HO + *HSieu am

'(20 - 40 kHz)

6H2O va nang lugngH2O —"-^ *HO + *HBile xa n&ng

(1-10 Mev)

lugng cao

(Ngudn: Trdn Mqnh Tri- Tran Manh Trung, 2006)
^" Cac qua trinh oxi hoa nang cao nho tdc nhdn dnh sang
Cac qua trinh oxi hoa nang cao nho tac nhan anh sang la cac qua trinh
nho nang lugng buc xa tia cue tim UV, bao gom cac qua trinh dugc trinh bay
d bang 2.4.

GVHD: TliS. Truffng Kiin Tho

SVTH: Hd Van Thing

TranglO


Khoa ludn tdt nghep

Lop DH10MT

Bang 2.5: Cdc qua trinh oxi hoa ndng cao nhff tdc nhdn dnh sang
Tac nhan phan

TT

1

2

Phan ling dac trrnig

ling
H2O2 va nang

H2O2 -^-> 2*H0

lupng photon UV

(A = 220 nm)

03 va nang lupng

O3 + H2O —^ 2*HO

photon UV

(A= 253,7 nm)

Ten qua
trinh

UV/H2O2

UV/Oi
o y/vyj

H2O2+O3 + H2O —^ 4*HO +
•3

J

H2O2/O3 va nang

o2

lupng photon UV

UV/H2O2 +
o3

(A = 253,7 nm)
Fe3++H2O —^-> *HO +Fe2++ H*"

H2O2/Fe3+vanang

4

Fe2+ + H2O2 —^ Fe3++ OH"

lupng photon UV

Quang
Fenton

+*HO

TiO2 —^ e + h+
TiO2 va nang lupng

(A >387,5nm)

Quang xiic

photon UV

//+ + H2O^*HO^-Kr

tac ban din

h* + OH" -> *HO + H^

(Ngudn: Trdn Manh Tri- Tran Mqnh Trung, 2006)
^ Tinli hlnh nghien ci^u, dp dung cdc qua trinh oxi hoa ndng cao
Men nay
Nho mi the noi bat trong viec loai bo chat 6 nhiem huu co, dac biet la
nhilng chat huu co kho phan hiiy sinh hoc. Qua trinh oxi hoa nang cao dira
tren goc tu do *HO dupe xem nhu mot "chia khoa vdng" di gild cac bai toan
day thach thiic cua the k^ cho nganh xu: ly nude thai hien nay. Do la ly do tai
sao ngay nay cac qua trinh AOPs con dupe menh danh la cac qua trinh xu ly
nude thai cua the ky 21.

GVHD: ThS. Truong KiSn Thp

SVTH: Hd Van Thdng

Trang 11


Khoa hum tk nghipL&p DH1OMT

2.4. Mot so qua trinh oxi hoa nang cao da duoc nghien cii-u
2.4.1. Qua trinh oxi hoa nang cao khong nho' tac nhan anh sang

a) Qua trinh FENTON
Nam 1894 trong tap chi Hoi hoa hoc My da cong bo cong trinh nghien
ciiu cua J.H.Fenton, trong do ong quan sat thay phan ling oxi hoa axit malic

bang H2O2 da dupe gia tang manh khi co mat cac ion sat. Sau do, to hop H2O2
va muoi sat Fe2+ dupe sur dung lam tac nhan oxi hoa rat hieu qua cho nhieu doi
tupng rong rai cac chat him co va duoc mang ten " tac nhan Fenton " (Fenton

Reagent).

<^ Cochl
He tac nhan Fenton dong the (Fenton co dien) la mot hon hop gom cac
ion sit hoa tri 2 va H2O2, chiing tac dung voi nhau sinh ra cac goc tu do *HO, •
con Fe2+ bi oxi hoa thanh Fe3+.

Fe2+ + H2O2-^Fe3+ + *HO + Off(2.1)
Phan ling nay duoc gpi la phan ling Fenton vi Fenton la ngubi dau tien da
mo ta qua trinh nay nam 1894.
Nhung ion Fe2+ mat di se dupe tai sinh lai nho Fe3+ tac dung voi H2O2
du theo phan ling:
Fe3+ + H2O2-^ Fe2+ + H^ + *HO2(2.2)
Tir nhung phan ling tren chung to tac dung cua sat dong vai tro la chat
xiic tac. Qua trinh khii Fe3+ thanh Fe2+ xay ra rit cham, hing s6 t6c dp phan
ling rat nho so voi phan ling (2.1), vi vay sit ton tai sau phan ling chu y^u 0
dang Fe3+.

Goc *HO sinh ra co kha nang phan ling voi Fe2+ va H2O2, nhung quan
trong nhat la la co kha nang phan ling voi nhigu chit him co tao thanh cac g6c
huu co co kha nang phan ling cao.
*HO + H2O2 -> H2O + *HO2(2.3)
*HO + Fe2+ ->• OH' + Fe3+(2.4)

*HO + RH -^ H2O + *R(2.5)

GVHD: ThS. TruongKiin TitoTrang 12

SVTH: H6 Van Thing