A P D U N G T H A N
TfCH
D 6 N G LUANCHUYiN VAT
CHAT"D i CAI T H I E N Q U A N Ly TAI NHA UkY XCf LY CHAT THAI RAN HOTU CO
CAUDI§N-HANOI
PGS.TS Nguyen Thj Kim Thai Trudng Dai hgc XSy dung NCS. Nghiem Van Khanh Trudng Dai hgc Kidn trite Ha Ndi
Tdm tat: Bai bao trinh bay kit qua ap dung ddng luan ehuyin vat ehat di xac dinh lugng ehat dinh dudng (Ni ta.Caebon) bj that thoat trong qua trinh xifly khi khdng cd kiim soat tdi Uu eae thdng sd van hanh nhu luu lugng khi cap eho qua trinh xif ly, dp am, nhidt dp, t} Id phdi trdn phSn bun va chat thai. Diiu nay da gay ndn eae hidn tugng d nhidm mdi trudng, giam chat lugng san pham va tieu hao nhiiu didn nSng eho qua trinh xif ly. Kit qua nghidn cifu ehl ra ring, phan tich ddng luan chuyin vat ehat (MFA) ed thi dugc eoi nhu mpt cdng eu eho Ban giam ddc nha may xem xdt, eai tien eae didu kidn van hanh di nang cao hieu qua xifly, quay vong eae chat dinh dudng tU chat thai phuc vu ndng nghidp eung nhu gin giQ mdi trudna xuna auanh duae tdt han.
Summary: The paper presented results from application of Material Flow Analysis (MFA) to quantify of nutrients (Nitrogien and Cacbon) to be lost during tretament process with put controling of operational parameter such as air flow, moisture contents, temperature as well as fecal sludge: organic waste ratio. This caused the pollution situation, reduction of compost quality and high energy consumption. The results of study showed that, MFA ean be used as a tool for Management Board of the plant to modifying the operational procedures to improve efficiency of the treatment process, recycling of nutrients from the waste to agriculture as well as to keep better environment for surrounding areas.
i«10 DAU
Trong qua trinh u sinh hpc chat thai huu cP thi thanh phin quan trpng nhit can kiim soat la nguyen td Nito vd Cacbon. Vi vay, vdi ty le nito thu dupc trong san pham mdn hCru co ehi cd 17% (so vdi tdng lupng nito trong hdn hpp phan rac trudc khi dua vao u) la qua thap va chung ta hodn toan ed the tang ty le nay bing hang loat eae bien phap ky thuat va phi ky thuat de giam thieu luong that thoat nito xudng thip nhit cd t h i .
Thdnh phan mun hifu cP la mpt trong nhung chi tieu quan trpng de danh gia san pham chat lupng phan hdu cP. Hien nay, tdng lupng cacbon hifu eo bi tdn thit trong qua trinh xd ly cda nha may len tOi gan 70% lam eho chat lupng mun dau ra thap hon so vdi tieu ehuan phan huu CO khodng vd phan hOfu co sinh hpc, do dd nha may thudng phai bd sung them mdi dat yeu cau Dieu nay lam tang gia thdnh ban phan bdn.
TAP CHf KHOA HOC C O N G NGH6 XAY DUNG Sd01-9/2007 79
Cdng cu Phan tich Ddng luan ehuyen Vat chit (MFA) gidp cho cae nha quan ly biit dupe cac nguyen nhan gay thit thoat cae thanh phin dinh dudng (Nito, Phdt pho vd Cacbon) trong qua trinh xd ly va du bao dupe khdi lUpng cy t h i cda tdng chat dinh dudng vao mdi trudng dit, nudc va khi. Td dd, cd t h i d i ra eae bien phap thich hpp de quan ly tan thu chdng vd gdp phin giam thieu d nhiem mdi trudng.
Cdng cu MFA dupe dp dung trong quan ly mdi trudng d mdt sd nudc nhU Nhat Ban, Thuy Sy... d Viet Nam, MFA dupc img dung dudi dang can bang vat chit trong cac qua trinh san xuit cong nghiep dae biet trong kiim toan chat thai d pham vi nhd, ehUa mang tinh tdng hpp.
Vdi sy hd trp eda eae chuyen gia td Khoa NUdc va ve sinh (SANDEC), Vien Khoa hpc Cdng nghe Lien bang Thuy Sy trong khudn khd eda du an Nang eao nang lyc nghien cuu trong quan ly phan bun (FSM/ESTNVII), vide ap dung MFA dupe tie'n hanh trong phan tich he thdng vd sinh mdi trudng tai thanh phd Viet Tri (nam 2002), thi xa VTnh Yen tinh VTnh Phuc (nam 2004), thdnh phd Ha Npi (nam 2006) da gdp phin gidp eho cac nha quan ly mdi trudng va cic CO sd xd ly chit thai tai cac dia phuong tren cd dupe CP sd khoa hpc de lap eae k i hoaeh quan ly mdi trudng cdng nhu ke hoach van hanh cae tram xd ly chit thai tdt hon nhim giam tdi mdc tdi thiiu cac chit gay d nhiem mdi trudng va tan thu eae thdnh phan dinh dudng cd trong chit thai quay trd lai phue vu cdy trdng tai cae khu ven ngoai eung nhu cac vdng ndng nghiep.
PhUdng phap nghien curu:
- Nghien eiru ly thuyet co ban ve phan tich ddng luan chuyen vat chit (MFA).
- Khao sat thuc te tai co sd nghien cdu.
- Ap dung eae budc MFA de dy bao nguyen nhan gdy d nhiem mdi trudng vd kha nang thu hdi chit dinh dudng td chat thai phue vu eay trdng;
K i t qua nghien cifu;
Hoaf ddng ehung eOa nha may: Nha may xd ly chat thai hifu co C i u Diin bit d i u di vao hoat ddng td ndm 2002 la mdt trong nhifng nhd may di d i u trong vide dp dung edng nghd d sinh hpc d i xd ly chit thai hCru cP d Vidt Nam.
Cdng suit theo thiit ke la 210 tan/ngay. Cdng suit thue t i dao dpng td 100 - 140 tin rac/ngay. San pham phan hdu co khoang 20 - 25 tan/ngay.
Thanh phin rac thai vdi ty le % eae chit theo khdi lupng dupc phan tieh va trinh bdy trong bang 1.
Bang 1. Kit qua phSn loai thanh phin rSe thai dUa din xifly tai nhS may Thanh phan
- La eay, rac hdu co - Giay vun
- Plastic
- Kim loai, vd hop
T'}le%
theo khdi lugng 59,0 - 65,0
2,2 4,3 1,6
Thanh phin Thuy tinh
- D i t da va cac chit tro khac.
- Op am (%) Ty trpng (tin/m')
T}le%
theo khdi lugng 2,5 30,3 49,8 0,44 (Ngudn: Bao eao kit qua phan tieh eita Phdng Chat thai rSn CEETIA, 2005 vS 2006)
80 TAP CHf KHOA HOC C O N G N G H 6 XAY DUNG sd 01-9/2007
Nghidn cdu da dupc tien hanh tren co sd xem xet su chuyen hoa eae thanh phan hdu co trong rdc thai theo tdng cdng doan xd ly theo ty Id % d i u vao. Ridng ddi vdi cac thanh phan bd sung trong tdng qua trinh biin ddi nhu EM, phu gia, nude, phan bun, khdng khi,... dupc xac djnh va quy ddi ridng theo don vi tin/ngay. Cac san pham va qua trinh cda ddng luan ehuyen vat chit trong hd thd'ng Nhd may che bien phdn hdu co C i u Dien dupc tdng hpp va trinh bay trong bang 2. So dd ddng luan chuyen vat chit qua cac qua trinh di vao va di ra khdi nha may dupc the hien tren hinh 1
Bang 2. Cae san pham va qua trinh eOa ddng luSn ehuyin vat chat trong nha Cdng doan san xuat
cda nha may
TuyenlUa
U len men
,
Cl chin
Tinh che
Tuyin ty trpng va ddng bao (hodn thien san phim)
San pham diu vao - Chit hiJM CO - Giiy, gd - Kim loai Thuy tinh - Chit tro, d i t da - Plastic
- Chit khd mui EM - Chit diet rudi - Chit hiAj CO - Cac tap chit - Phan bun tu hoai - Men vi sinh EM - Nudc (dp am) - Khdng khi (oxy) - Nudc (dd am) - Khdng khi (oxy) - Chit hdu eo da len men
- Phan compost (chua tinh ehi)
- N , P , K - Mdn loai 1 va 2
Sd lugng
(%)
59,1 2,2 1,6 2,5 30,3
4,3
59,1 7,4
54,9 54,9
25,5
San pham diu ra - Vat edng kinh - Chit hOru eo - Chit vd CO - Chit hdu CO kich thude Idn
- Nudc rac - Hoi nude - Chit hdu CP da len men
- Hoi nudc - Phan compost (chua tinh chi) - Chit deo - Giiy - Vat nhd
Tap chit Idn - Mun loai 1, 2 - Chit khdng len men (chit tro)
Thuy tinh Tap chit - Mun hdu CO (tinh)
may Sd lugng
(%)
2,2 53,8 38,7 5,3
54,9
54,9
4,3 0,5 0,6 12,4 25,5 11.6 0,6 7,3 17,6
Tinh todn can bing vat chat theo su bien ddi cua Nito: Cac chat chda N r i t phong phd vd da dang ndn so dd la phdc tgp. Mpt sd dang tdn tgi cda Nito trong qua trinh xd ly bao odm;
TAP CHi KHOA HOC C O N G NGHt XAY DUNG sd 01-9/2007 81
NOj; trong mudi hoa tan Nj: Khi
NO; dang khi
NH3; khi N2O3; dang khi N2O: dgng khi
NOj: dang khi
NHj*: trong mudi hoa tan
Ddng Nito chiim Uu t h i dUdi dang Nito phan td.
De cdn bing dupc sy biin ddi v i lupng cda nguyen td nito trong toan bp quy trinh san xuit cda nha may, vide tinh toan theo cae sd lieu nghien cdu vd phan tich thi nghiem da dupc tiin hanh. Kit qua dupc trinh bay trong bang 3.
Tinh toan can bing vat chat theo su bie'n ddi cua Cacbon:
Tuong ty nhu each tinh toan d tren, va so dd can bang nguyen td C dupc minh hoa tren hinh 3.
Bang 3. Bang thdng kd eae thdng sd vat ehat va eae qua trinh biin doi eda nguydn td nita trong qua trinh xCrly ehat thai hUu ea
Thanh phin eae ehat
Dau vao
D i u ra
Chit thai hOfu eo Phan bdn b i ty hoai Hdn hpp phan rac sau dao trpn Nudc c i p vao be u va khu dao trpn Nude ri rac tham nhap vao ngudn nudc Nude bay hoi (dang khO
Hdn hpp phan rac sau d len men Hdn hpp phan rac sau d chin Mun sau tinh ehe
Sd lugng 94,66 tan/ngdy
28 tin/ngay
122,66 tan/ngay
105 mg/l va 118.6 g/l 105 mg/l
va 118.6 g/l
301,3 mg/l 121,22 tan/ngay
123 tin/ngay
79,7 tan/ngay
Dgn vj quy doi (mg/l) 354,1 576,6 534,5 105,0 va
118,6 105,0 va
118,6 301,3 275,4 233,2 90,6
Qua trinh gd'c Khu dan cUva chp
Khu dan cu Phan loai B i chda nude sinh hoat
Trong rac hdu
CO
Trong hdn hpp phan rac Dao trpn Be d len men Be d chin
Cdng doan Phan loai, bd sung phu gia Tram xd ly phan bun eda nha may Dao trpn
Cac b i u
Be d va dao tron
Tai cac be d Be d len men Be d chin Khu tinh c h i
(Ghi chu: Viec tinh toan quy doi dan vi duge xae dinh trdn ea sd dp am cOa eae ehat va 1} Id % trong lugng khd eua nguydn td Nita trong mdi ehat dd)
82 TAP CHi KHOA HOC CONG NGHE XAY DUNG SO Of-9/2007
R A C T H A I O I / A VAO;
C H A ' T Hijru CO 59,1% KIMLOAM,6%
GIAY G 6 2,2% PLASTIC 4,3%
T H U ' * ' T I N H 2 , 5 % C H A T T R O 3 0 , 3 % D 6 X M T R U N G B J N H C U A FJAC T H A I 49,8%
B b SUNG EMTC KHCT M U I I L I T / T A N , C H A T D I E T R U O I
D U O N G BIEN G l d l C U A HE
THONG
VAT CONG KENH
CHAT H Q U CO L 6 N
5,3% CHAT HLfU CO LdN
CHA'T V 6 CO
CHAT HiJfU CO
2,2% GIAY / GO
1,6% KIM LOAI 4,3% CHAT DEO 30,3% OAT OA 2,5% THUY TINH 53,8% (DE XLf LY)
5,3% MAY NGHIEN
LOAI 8 0 LAN 1:
33,5%
1,6% KIM LOAI 27,4% CHAT TRO 1,9% THUY TINH 1,7% GIAY 0,9% PHAN VUN BO SUNG PHAN BUN TU HOAI; EM; NUOC DE T A N G 0 0 AM
11.6% CHAT BAY HOI
NUdc Rl RAC TLT CAC B^ 0? ^COMPOST:
KHONG KHi (QUAT GIO OE TANG
CUONG OXY) LOAI 80 LAN 2: 29,4%
4,3% CHAT DEO 11,6% KHONG LEN MEN 0,5% GIAY
0,6% VAT NHO
12,4% LOAI NHd SANG D U O N G BIEN HE THONG BAN TUY^N
TY TRONG
LOAI BO LAN 3: 7,9%
0,6% THUY TINH
7,3% LOAI NHO TY TRONG
I ( 1 7 , 6 %
I SAN PHAM COMPOST 17,6%
VAT LIEU TAI CHE
10,1% LOAI BO 72,3%
Hinh 1. Sa dd eSn bing ddng v$t chit cho he thdng xifly ehat thai hCfu ea tai Cau DiSn, Ha Ndi
TAP CHi KHOA HOC C O N G N G H E XAY DUNG SO Of-9/2007 83
Nhan xet kit qua phan tich va can bing Nito Bang 3 cho thiy, trong qua trinh d len men va d chin, lupng nito da bj that thoat do bay hoi la r i t Idn, so vdi lupng nitP cd trong hdn hpp phan rac trUde khi dua vao xd ly thi lupng nito bi that thoat di vao khi quyen chiem tdi 56,4% va 41,76 % thit thoat vao mdi trudng nude. Nhu vay sau qua trinh xd ly, tdng lupng ni to edn lai trong mdn hdu co la 1,84%, trong khi dd san pham mun hdu co td nha may xd ly rac thai tai Bang Cdc - Thai Lan, ty Id nay dat 2,05 % (Hinh 2).
Hinh 2. Chat lugng mun hCfu ca tai Thai Lan
RAC THAI OE'N NHA M A Y
BAY HOI VAO KHI QUYEN
I OUdNGBlEN I eidicuAHl
TH6NG
NUdc Rl RAC
VAO N G U 6 N NUdc
NUOC Kl ^AC
T,1=CHAT T L , BAI C-i^?. L A P
OON VI TiNH: MGIL
:®
OAO TRON&[
P H A N B U N T y HOAI1474,
^'®1Z
LEN MEN ( 8 7 2 , 2C^02fi\
BAY HC3I VAO KHI QUYEN
BAY -(Ol VAO KHI QUYE^
425,6
• PPHANLOAI if' N. SANPHAMMUNI
^ ^ * " ' ' ° - ' ISANGTINHCHEfV^J^*!^ COMPOST 1
Hinh 3. Sa dd can bSng nguydn td Cacbon trong qua trinh ehuyin hoa
84 TAP CHf KHOA HOC CONG N G H $ XAY DUNG SO Of - 9/2007
KET LUAN
- Ket qua nghien ciru dien hinh MFA tai Nha may xd ly chat thai hiJru co C i u Diin cho thay che dp cung cap dxy cho qua trinh xd ly chua tdi uu dan den tieu hao ndng lupng cho hoat dpng xd ly qua Idn va chi phi van hanh hien kha cao. Vide xd ly phdi hpp rac thai huu co va phan bun chua dupc lupng hoa ma dang d trang thai tuy tien thie'u hpp ly... nen mpt lupng Idn cae chit dinh dudng N. P. C... da bj thit thoat vao mdi tm'dng nude, da't va khdng khi gay ra cdc hien tupng 6 nhiim khdng ed kiim soat. Theo tinh toan can bang vat chat cho cic nguyen td N, C, chung ta cd the djnh IUpng dupc ham lupng chat hifu co trong mun ehi cdn td 7 - 12%, mpt lupng I6n Cacbon va Nito da bj that thoat vao moi trUdng da't, nude;
- Nghien ciru cung cho thay, viee ap dung tdt cac giai phap cai tiin ve ky thuat van hanh, kinh te - tai chinh... nha may cd t h i tiit kiem dupc nang lupng tieu hao de cung c i p khi cho qua trinh xd ly, cai thien chat lupng s i n pham do lupng chat dinh dUdng dupc quay vdng cao ddng thdi duy tri dupc c h i dd tdi Uu cho qua trinh xd ly.
Trong thdi gian tdi, viec tap trung nghien edu ehe dd oxy tdi uu, xac dinh ty le phdi trdn phan bdn ty hoai va rac thai hdu co phd hop vdi thdnh phin va tinh chit rac thai Viet Nam,... la rit can thiit de nang cao hieu qua xd ly chat thai hiJru co bang phuong phap d sinh hpc, tie'n tdi dng dyng cdng cy MFA de quan ly van hanh cho cac nha may trong pham vi ea nude.
Tai lieu tham khao
1. 86 Y fe, Cdng ty BURGEAP, DU thao Bao eao qui hoach tdng t h i xd ly chit thai ran y te tai Viet Nam. Dy an do Chinh phd Phap Tai trp, 2003
2. Trung tam ky thuSt mdi trudng do thi va khu edng nghidp (CEETIA) - Cac tU lieu quan trie ve chat thai r i n va chit thai nguy hai d Viet Nam nam 2000 d i n 2006.
3. Du an SDC, Trung tam ky thuat mdi tn/dng dd thj va khu cdng nghidp (CEETIA). Kit qua nghien cdu xd ly phdi trdn phan bun rac thai huu eo trong diiu kien Viet Nam, 2006.
4. 86 TSI nguydn vS Mdi trudng - Cue Bao vd Mdi trudng - Bao eao hien trang mdi trudng Viet Nam nam 2000 d i n 2005.
5. NgSn hSng Thi gidi. Cue Bao ve Mdi tn/dng, 2004. Bao cao diin biin mdi trudng Viet Nam.
Chat thai r i n , nam 2004.
TAP CHf KHOA HOC CONG NGH^ XAY DUNG sOOf-9/2007 85