NGHIEN CUtJ tTNG DUNG CONG NGHE SINH H O C K Y K H I
K E T HOP MANG VI L O G D E XtT L Y NlTO^C THAI DO T H I Of
V I E T NAM
APPLICATION OF ANAEROBIC MEMBRANE B I O R E A T O R
T R E A T I N G MUNICIPAL W A S T E W A T E R IN V I E T N A M
T S Trkn

T h i Viet Nga, K S . Nguyen Dire Canh, C N Nguyen Thiiy L i e n , T h S
Du-oTig T h u H2ng

Bo mon Cap thodt nu&c, Khoa Ky thudt Mdi tj-u&ng, Truarng Dai hoc Xdy dimg
Diachi:55 Gidiphdng, Hd Ndi, Viet Nam. Email: [email protected]

Tom tat
Ldn dau tien a Viet Nam viec nghien ciru img dung cdng nghe sinh hoc ky khi kit hop vdi qud trinh
loc mang (goi tdt la AnMBR) de xie ly nude thdi dd thi dupe thuc hien cd d quy md phong thi nghiem
va quy md pilot tai hien trudng. Hai hi thdng AnMBR dupe van hanh song song trong phong thi
nghiem, xie ly hai loai nude thdi sinh hoat khdc nhau: hi thdng Rl xie ly nude den cua mot chung cu
d Hd Ndi (COD 300-800mg/l, BOD: 180-350mg/l, NH.,-N: 40-85 mg/L) va hi thdng R2 xie ly nude
thdi thu gom tie hi thdng cdng chung (COD 150-300mg/l, BOD: 60-250mg/l, NHyN: 5-45 mg/L). Cd
hai md hinh dupe van hanh vdi thdi gian luu thuy luc thay ddi tie 48 gid xudng din 6 gid trong
khodng 550 ngay liin tuc trong dieu kien nhiet dd mdi ti-udng. Kit qud cho thay hieu qnd xie ly chat d
nhiim theo TSS, BOD, COD rat cao va on dinh vdi cd hai md hinh (Nude sau xie ly cd TSS
can phai xu ly tiep bang cac qua trinh sinh hoc hieu khi trudc khi xa ra mdi trudug. De khac
phuc cac nhugc diem nay, viec ket hop cdng trinh sinh hgc ky khi va mang vi loc (cdng nghe
AnMBR) dugc nghien cuu va phat tridn trong nhung nam gan day [2, 3,4].
Mot he thdng AnMBR dien hinh bao gdm: be sinh hoc ky khi ddng vai trd la cdng trinh len men
metan va bd phan mang vi loc de phan tach nude thai va bun sinh hgc [2]. Nude thai sau khi
phan huy ky khi se di qua bd phan mang vi Igc, vdi kich thudc Id pho bien tir 0.1-0.4 micromet.
Khi sinh hgc dugc thu hdi va du tru d cdng trinh rieng cho muc dich tao nang lugug dimg trong
tram xir ly. Cac ket qua nghien cuu cho thay cdng nghe nay cd nhieu uu diem so vdi cdng nghe
xir ly sinh hgc truyen thdng khac nhu: giam tieu thu nang luoug do khdng can cung cap oxy cho
qua trinh phan huy chat huu co; giam khoi tich bun tao thanh; thu hdi dugc khi biogas lam nang
luoug sinh hoc; hoat ddng dn dinh, ngay ca d cac tram cdng suat nhd; xir ly tai lugng d nhiem
Idu, kich thudc va dien tich cdng trinh xir ly sinh hoc nhd, phii hgp vdi khu vuc cd quy d§t eo
hep [2, 3]. Ngoai ra, cdng nghe AnMBR tiet kiem chi phi xay dung cdng trinh ling thu cip,
cdng trinh loc va giam chi phi xay dung cac cdng trinh xir ly bun can len men do lugng biin can
sinh ra nhd [2]. Nhd vai trd cua mang vi Igc, nude sau xir ly cd chat lugng tdt, cd the dap ung
nhu cau tai su dung trong ndng nghiep, giai quyet van de thieu nude tai cac vimg dd thi va ven
dd.
Day la hudng nghien cuu mdi cd tiem nang ung dung d didu kien khi hau nhiet ddi de x u ly
nude thai dat hieu cjua loai bd chit d nhiim cao, chi phi van hanh hgp ly, ddng thdi thu hdi dugc
khi me tan tir he thdng xir ly lam ngudn nang lugng sinh nhiet hay phat dien. Nghien cuu nay do
do dugc tien hanh vdi muc tieu chinh la nghien cuu img dung cdng nghe AnMBR d l xu ly nude
thai dd thi d Viet Nam.

M6 hinh AnMBR trong phong thi nghiem
Md ta he thdng
Hai he thdng AnMBR quy md phong thi nghiem dugc l4p dat theo so do d Hinh 1. Mot he thong
bao gdm: be phan ung ky khi (dung tich hixu dung 5 lit), bd mang v i Igc mini, may nen khi va he
thdng sue khi trong be phan ung, he thdng thu khi sinh hgc, va he thdng bom nap nude thai, bom
hiit qua mang. Mang vi Igc su dung trong md hinh la dang mang tam phSng, cd dien tich Igc be
2

Hinh 1. So do he thong AnMBR quy md phong thi nghiem.
Md hinii dugc van hanh trong hon 500 ngay vdi cac che dd thdi gian luu thiiy lire va va tai trgng
chat huu CO khac nhau de danh gia ve hieu qua xu ly. Thdi gian luu nude thuy luc (HRT) thay
ddi tir 48 gid, 36 gid, 25 gid va 12 gid, va 8 gid vdi He thdng R l , va van hanh them ca d thdi
gian luu 6 gid vdi he thdng R2 de xac djnh gia trj HRT thich hgp cho timg loai nude thai. Bim
dugc luu giu hoan toan trong he thdng, tuy nhien mot lugng bun cd the tich lOOmL dugc lay tir
be ky khi ra vdi tan suat 1 tuan mot Ian de phan tich danh gia cac thdng sd ciia qua trinh x i i ly
sinh hgc. Ket qua van hanh md hinh R l dugc the hien d cac dd thi va vdi md hinh R2 dugc trinh
bay d Bang 1.
Cac chi tieu DO, pH, nhiet dd cua nude thai dau vao, nude sau xu ly, va nude trong bd phan ling
sinh hgc dugc do dac hang ngay hdi cac thiet bi do nhanh. Viec lay mau nude de phan tich cac
chi tieu COD, BOD, ham lugng chat rin la lung (MLSS), chat rkn la lung dd bay hoi (MLVSS),
Nita tdng so (TN), Amdni (NH4-N), Phot pho tong sd (T-P) Sunfat, dd kiem dugc thuc hien 1
Ian trong 1 tuan. Vide phan tich tuan thii cac phuong phap tidu chu4n (APHA 2003) va phuong
phap HACH vdi thiet bj do quang pho DR2100 (HACH, USA). Khi sinh hgc dugc thu gom va
phan tich thanh phan khi (1 Ian 1 tuan) bSng thiet bj do nhanh test kit GAC25 (Nhat Ban).
Hieu qua xu- ly cua he thong AnMBR
Vdi md hinh R l xir ly nude thai cua tda nha chung cu, kdt qua phan tich cho thay ndng dd biin
tang dan tuong ung vdi tai trgng chat huu co (theo COD) va dat gia tri 12.000-14.000 mg/L d
cudi thdi gian van hanh. Hinh 2 bidu didn su dao ddng ciia COD dau vao va dau ra sau khi xir ly.
Ham lugng COD trong nude thai thd dao ddng tir 180-930 mg/L. Ham luong COD sau khi xu ly
trong sudt thdi gian van hanh md hinh kha dn djnh va deu nhd hon 100 mg/L. Ndng dd BOD
trong nude sau xir ly cung on djnh va nhd hon 30 mg/L, cho th^y he thdng AnMBR hieu qua
trong viec x u ly chat hun co vdi hieu suat xu ly COD tir 78-95%, hieu suat xir ly BOD dat tir 8088%, dap img dugc tieu chuan xa thai ra mdi trudng (QCVN 14:2008/BTNMT, ngudn loai B).
Do dac thii nude thai dau vao la nude den tir he thdng thu gom nude thai trong tda nha chung cu
nen ham luong Amdni kha cao, dao dgng tir klroang 50 - 160 mgN/L. Ham lugng Amdni trong
3


niroc dau ra cung d dai tuong tu cho thiy d trong dieu kien yem khi thi Amdni la thanh phan

HRT (gia)
Thoi gian van hanh
(ngay)
Tai trong C H C
(kgCOD/m/d)
Flux (mVm-.d)
Nhiet d6 CC).
Chat luong nuoc sau xu ly
COD(mgA)
NH4-N (mgN/L)
T K N (mg/L)
T-P (mg/L)

Phai

1

Pha2

|

Pha 3

|

Pha 4

|

PhaS


0.19-0.65

0.22-1.58

0.04-0.18
28-31

0.05-0.13
• 18-28.5

0.03-0.08
11-26

0.06-0.17
24-30

0.12-0.25
25-29.5

0.13-0.36
14-29

32.3"
30.5
32.9
3.9

40.8"
38.3

Nang suat sinh khi (Ud)

7.6-8.2

8.1-8.4

8.0-8.3

6.9-8.6

7.2-8.2

0.39"

0.21"

0.11"

0.22"

28-30
0.37"

Tac nghen mang loc
Trong suot thdi gian van hanh, ndng dd bun (MLVSS) trong be ky khi ciia ca hai md hinh deu
tang dan. Vdi md hinh R l xii ly nude thai ciia chung cu, he thdng hoat ddng dn dinh khi ndng dd
bun nhd hou miic khoang 14.000 mg/L, ndng dd bun vugt qua miic nay thi Ap suat qua mang
(TMP) tang cao va mang bj tac (Hinh 3), do do ndng dd bun dugc duy tri trong khoang 12,000 14,000 mg/L). Ngoai ra, khi thdi gian luu nude giam xuong miic 6 gid thi mang ludn bi tac do
thdng lugug qua mang tang cao, do do HRT tdi uu ciia he thdng R l dugc xac djnh la 8 gid. O
md hinh R2 xii ly nude thai d tram Kim Lien, ndng dd bun d cudi giai doan van hanh (HRT=6


250 300

350 400

450 500

550.. 600

650

ngay

Hinh 3. Su thay ddi Ap suit (TMP) va Thdng lugug Igc (Flux) trong sudt thdi gian van hanh md hinh R l
r

He thong AnMBR quy mo hien truong

5


Dira tren k i t qua thu dugc sau gin 2 nam nghien cuu
trong phong thi nghiem va vai su ho trg ve cong nghe
va thidt bj tir Trung tam Nghidn cuu va Phat tridn
Cong nghe cua Tap doan KUBOTA (Nhat ban), mot
mo hinh pilot co cong suat 3-5 m^/ngay dugc thidt ke
va l i p dat dd xir ly nuoc thai sinh hoat cua Ky tuc xa
sinh vidn cua trudng Dai hgc Xay dung.
He thdng pilot AnMBR cd ngan thu ket hgp bd didu
hda, mot bd phan ung sinh hgc kdt hgp mang Igc va

thd dap ung tidu chuan xa thai vd chat dinh dudng (N,P).
Bang 2 Hieu qua xir ly cua he thong AnMBR xir ly nude thai ky tiic xa quy md pilot
TT

Th6ngs6

Don vj

Gia tri trung binh
Nude thai tho
Sau xir ly
370
65

1

COD

mg/L

2

Amoni (NH4-N)

mg/L

105

3


kg CH^hgCOD xii ly

0.231

San luong khi sinh hoc cua mo hinh AnMBR tuong doi cao. T6ng luong khi sinh ra dat cao nh4t
650 lit/ngay (tuong ung vdi 500 lit CH4/ngay), trung binh dat khoang 370L/ngay va ty le sinh
khi CH4 la 0.231 m--CH4/lkgC0D. Ham luong khi me tan (CH4) trong khi sinh hoc tuong ddi
cao, dat 78%.

0

20

40

60

80

100

120

140

160

180

ngay

tren mang lam giam toe do Igc, tang tdn thdt qua mang Igc va tang chi phi nang lugng ciia he
thdng bom; chi phi dau tu ban dau ldn; va he thong dieu khien tuong ddi phuc tap.

K E T LUAN
Trong nghien cuu nay, md hinh xir ly nude thai ung dung cdng nghe sinh hgc ky khi ket hgp vdi
mang vi Igc dat ngap (AnMBR) de xu ly nude thai sinh hoat dd thi trong dieu kien khi hau nhiet
ddi quy md phong thi nghiem va pilot da dugc xay dung va trien khai. Ket qua van hanh hai md
hinh lien tuc trong hon 550 ngay cho thay vdi cac dieu kien khac nhau ve thdi gian luu thiiy lire
va tai trgng chat huu co thi hieu suat xu ly chat huu co (COD, BOD) deu rat dn dinh va d miic
cao (80-90%). Tuy nhien ham lugng Nita (TN, N H 4 - N ) d nude sau xu ly hau nhu khdng khac
nude thai chua xii ly, cho thay co che x i i ly ciia cdng nghe AnMBR khdng loai bd dugc Nito'.
Ddi vdi ngudn thai cd ham lugng N , P cao c4n dugc tiep tuc xtr ly de loai bd Nita nham dap ling
dugc tieu chuan xa thai hieu hanh. Cac ket qua nghien ciiu cho thay cdng nghe MBR ky khi
khdng chi phu hop d l xu ly loai nude thai chiia ndng dd chat huu co cao nhu nude thai tu cdng
nghiep bia, rugu, tinh bdt [5] [6], ma con rat hieu qua trong viec x i i ly nude thai dd thj cd ham
lugng dinh dudng thip. He thong xii ly cd chi phi van hanh thap hon so vdi cac cdng trinh xii ly
hieu khi cung cdng suat do khdng phai van hanh he thdng cap khi cho qua trinh phan hiiy sinh
hoc hilu khi, ngoai ra cd t h i tan thu dugc ngudn khi sinh hgc, cd the tao nang lugng cap nhiet
hay phat dien.
Vdi cac uu thd ve hieu qua x i i ly cao, he thdng cdng trinh ggn nhe va tieu tdn it nang lugng,
cdng nghe AnMBR cho thay cd t i l m nang ap dung ldn d nhung nai eo hep ve quy dat va khdng
cd dieu kien xii ly ve bim can nhu khu vuc dd thi.
Loi cam en: Nghien cu-u nay dugc thuc hien trong khudn kho de tai N C K H trong diem
cua Bo Xay dung (B2012-03-03) va du an hgp tac nghien cuu vdi Trung tam Nghien cuu
va Phat trien cua tap doan Kubota.
TAI L I E U THAM KHAO
1. Munariatis I . D. and Grigoropoulos S. G. - Low-strength wastewater treatment using an
anaerobic baffled reactor" Water Environment Research, 74 (2002) 170-177.
2. Sutton P.M., Berube P., and Hall E.R. - Membrane Bioreactors for Anaerobic Treatment of
Wastewaters. Final report- WERF Project 02-CTS-4 (2004). Water Environment Research