ANH HU6NG CUA NU6C SONG TO LICH D^N M 6 I TRUCJNG VA StrC KHOE NGU61
DAN6 KHU VUC VEN
S 6 N GNGUYfiN THI BICH NGUY$T * 1. Dat vin de
Sdng Td Lich, bit diu ttt cdng Phan Dinh Phttng (quin Ba Dinh), la dilm Id dien tten mit cua muong Thuy Khue, chay dpc dudng Thuy Khue vl phfa chp Budi, cit ngang qua dudng Lac Long Quin rdi tdi dudng Hoang Qude Viet. Sdng Td Lich dupc thi hien trdn ban dd thinh phd Ha Ndi tfnh ttt dudng Hoing Qude Viet vdi chilu rdng trang binh cia sdng tai diy xip XI 30 m, va dd siu khoang 3 m. Ttt dudng Hoing Qude Viet, sdng chay dpc dudng Budi tdi Ciu Giiy, rdi theo dudng Ling tdi Ciu Mdi. Doan sdng nay cd chilu rdng dao ddng trong khoang 30-40 m, chilu siu ttt 3-4 m. San dd, sdng Td Lich tilp tuc chay dpc theo dudng Kim Giang, Dai Kim, Thmh Liet vl phfa Nam Tp. H i Ndi. t d i khu vyc Nhi miy Son Ha Ndi, sdng Td Lich re nhinh, mdt nhinh chay sang hudng Ddng dd vl sdng Kim Nguu (phfa hd Ydn Sd), mdt nhinh chay xudi theo hudng Nam qua ciu Td, vi dd vio sdng Nhud .
Sdng Td Lich l i mdt ttong 4 con sdng chfnh quan ttpng ttong hd thdng thoit nudc thai Ha Ndi. Nudc thai trdn sdng Td Lich chu ylu li nudc thai sinh boat vi mdt phin Ii nudc thai cdng nghidp.
Sy hinh thanh hydrd sunfua ttong nudc thai la do qui ttinh phin biy cic hop chit huu co cd chia luu huynh hoic qua ttinh k h i sunphat do vi khuin xay ra ttong phin bun ling cua dudng cdng thoit nudc vd sinh vi nhung dudng ttue chfnh. Sunphit hoa tan xuit hien ttong nudc thai do nhung dilu kien sau:
- Nudc cd chia ft oxy boa tan.
Thdi gian tdn du liu ttong he thdng thu gom nudc cdng.
- Hpp chit hun co cd chia luu huynh.
Trong nudc thai, luu huynh cd ngudn gdc ttt 4 ngudn chinh nhu sau:
(1). Cac hpp chit vd co cd chia luu hu^nh nhu: sunphat, thiosunphat,... cd ttong ngudn nudc cip.
(2). Cic hpp chit vd co cd chia luu hu^nh nhu: sunphat, thiosunphat,... cd ttong ngudn ngim, nudc mat khic xim nhip vao he thdng thoit nudc.
(3). Cic hpp chit vd CO, protein ... cd chia luu huynh hoic sunphat vd co cd ttong nudc thai sinh hoat.
(4). Cic hpp chit vd co, httu co cd chia luu huynh cd ttong ngudn nudc thai cdng nghiep.
H2S ttong ty nhien sinh ra do cic qui trinh boat ddng cua nui lia vi sin phim cua qua trinh phin biy protein ddng vit vi thyc vit nhd sy tic ddng cua vi khuin. Rit nhilu loai vi khuin, nim thai ra HjS trong qui trinh phin buy cic chit chia cic axit amin cd luu huynh vi trong qua trinh k h i tryc tilp sunphat. Hydrd sunfua hinh thinh ttong nudc thai dupc sinh ra do boat ddng cua cic nhdm vi khuin ki khf Desulfovibrio (nhdm vi khuin gram im) vi Desulfotomaculum (nhdm vi khuin gram duong).
Mac dtt hydrd sunfua khdng ddng gdp true tilp vao hidn tupng iin ien toin ciu, nhung sy phit tin cua nd lai cd anh hudng din hidn tupng axit hda v i tic ddng din sic khoe. Khi HjS cd tilm ning axit hda (Acidification Potential) quy ddi tucmg duong 1,88 lin khf SO2, tilm ning ddc tfnh ddi vdi sic khoe (Human Toxicity I'otential) l i 0,22 lin quy ddi tuong duong hpp chit para-diclorobenzen (p-CeH4Cl2).
Hidn nay da cd nhilu nghien cihi vl hd thdng cip thoit nudc cflng nhu mdi tmdng cic
Nguyen Thi Bich Nguyit, Ths. Vifen NC M6i triremg vi Phit tri^n bin vumg.
IS
NguySn Thj Bich Nguydt - Anh hudng cda nudc sdng T6 Ljch den mdi trudng ddng sdng nhin nudc thai ttdn dia bin Tp. Ha
Ndi. Tuy nhidn, hiu hit nhttng nghidn ciu ndi tren chua dl cip dlh ngudn x i thai, kha ning phat thai mdt sd khf ddc cd anh hudng din sic khoe ngudi din vi giy tdn kem cflng nhu thiet hai cho he thdng thoit nudc thanh phd Hi Ndi. Do viy, bii bio niy dl cip din kit qui dinh gii chit lupng nudc sdng Td Lich,
kha ning phit thai khf H2S ttt con sdng nay vi nhttng anh hudng den sic khde ngudi din sdng d nhiing khu vyc cd sdng Td Lich di qua.
2. Anh hudng nudc sdng Td Lich den mdi trudng nude, khdng khi khu vyc ven song 2.1. Ddnh gid chdt lugng nudc tren song To Lich so vdi tiiu chuan nu&c mat
B A N G 1: Ket qua phin tfch chit lupng nudc sdng Td Ljch TT
1 2 3 4 5
Ky hieu m i u Nl N2 N3 N4 N5
pH
7,24 7,25 7,51 7,48 7,61
DO mg/l 0,48 0,26 0,12 0,18 0,22
COD mg/l 283 264 305 327 478
BOD, mg/l 162,4 144.8 168,4 186,2 218,6
Fe mg/l 0,68 0,72 0,56 0,62 0,41
TSS mg/l 448 480 553 528 530
NH4*
mg/l 22,4 18,6 14,6
•13,5 28,4
Vi tri Iiy miu Hoing Qude Viet Ciu Giiy Hda Muc Dinh Cdng Dip Thanh Liet
Gii tri pH cua sdng Td Lich do dupc dao ddng ttt 7,24 din 7,61, gii tri pH niy nim trong gidi ban quy chuin QCVN 08:2008/BrNMT (tidu chuin A l : pH ttt 6 din 8,5). Gii tti pH cd xu thi ting t i diu ngudn (Hoing Qude Viet - Nl) din cudi ngudn (Dip Thanh Lidt - N 5 ) .
Gii tri BOD5 cua sdng Td Lich do dupc dao ddng ttt 144,8 dl'n 218,6 mg/l, gii tti BOD5 nay vupt qui ri't nhilu so vdi quy chuin QCVN b8:2008/BTNMT (tidu chuin B2: < 25 mg/l). Gii tri niy ting ttt diu ngudn (Ciu Giiy - N2) din cudi ngudn (Dip Thanh Liet - N5).
Gii tri COD cua sdng Td Lich do dupc dao ddng ttt 264 din 478,0 mg/l, gii tii nay vupt qui quy chuin QCVN 08:2008/BTNMT cho phip (tieu chuin B2: <50 mg/I). Gii tri niy cd xu t h i ting ttt diu ngudn (Ciu Giiy - N2) din cudi ngudn (Dip Thanh Liet - N5).
Gia tri DO cua sdng Td Lich do dupc dao ddng ttt 0,12 din 0,48 mg/l, gii tri niy klidng dat tidu chuin QCVN 08:2008/BTNMT cho phip (tieu chuin B2: > 2 mg/l). Gii tri niy biln ddi theo tttng vi tri Iiy miu cd thi Ngtm ciru Phit triin bin vitng, si 1(34)- Thing 3/2012
do sdng Td Lich cd nhilu cia xa Idn vi hdi tu cua cic sdng nhinh.
Gii tri Fe cua sdng Td Lich do dupc dao ddng ttt 0,72 din 0,41 mg/I, gii tti niy nim ttong gidi ban tidu chuin QCVN 08:2008/BTNMT cho piiep (tieu chuin B2: 2 mgA). Gii tti nay cd xu thi giam xudng ttt diu ngudn (Ciu Giiy - N2) din cudi ngudn (Dip Thanh Liet - N5).
Gii tti TSS cua sdng Td Lich do dupc dao ddng ttt 448 din 553 mg/I, gii tri niy vupt qui tidu chuin QCVN 08:2008/BTNMT cho phep (tieu chuin B2: 100 mg/I) nhieu lin (ttt 4 din 6 lin). Gii tti niy cd xu thi tang ldn ttt diu ngudn (Hoing Qude Viet - N l ) din cudi ngudn (Dip Thanh Liet - N5).
Gii tri NH4+ cua sdng Td L4ch do dupc dao ddng tii i3,5 din 28,4 mg/l, gii tri niy vupt qui tiiu chuin QCVN 08:2008/BTNMT cho phep (tieu chuin B2: 1 mg/l) nhilu lin (ttt 14 din 28 lin). Gii tri niy biln ddi theo tttng vi tri Iiy miu cd thi do sdng Td Lich cd nhilu cia xa Idn va hdi tu cua cic muong nhinh.
2.2. Anh hudng nudc sdng din chdt lugng nu&c ngdm cua khu vuc ddn cu sdng ven sdng.
m
NguySn Thi Bich Nguydt - Anh hudng cOa nudc sdng Td Uch den mdi trudng ...
B A N G 2: Ket qua phin ti'ch miu nude gieng khoan Vitri
Iiy miu (each sdng) 50m 100m 150m
KMH NGl' NG2' NG3'
Ket qua do ngoai hien trudng t
°C 26 25,9 27,5
pH
7,18 7,39 7,63
DO (mg/l)
1,45 128 1,05
Dp due mg/l
102 45 37
CO D mg/l 48,0 592 69,3
BOD mg/l 25,46 30,11 40,05
Coliform MPN/lOOml
410 360 320
Nts mg/l
152 13,0 14,0
Pts mg/l 0,97 0,93 1,03
Kts mg/l 528 528 17,59 Theo bang phin tich, cho thiy chit Iupng
nudc sdng suy giam klo theo chit lupng nudc gilng khoan cua khu vyc ven sdng cflng bi anh hudng. Tit ca cic thdng sd ttdn dlu vupt qui tieu chuin nudc ngim cho phep. Gilng khoan d gin sdng cd cic chi sd d nhilm cao
hon so vdi cic gidng d xa sdng hon.
Chit Iupng nudc ngim tai khu vyc ven sdng dang bi 6 nhilm httu co.
2.3. Anh hu&ng nu&c sdng den chdt lugng mdi truarng khdng khi ven sdng Td Lich
Bang 3: Ket qua do HjS trong khdng khi khu vyc Thdn Trung va Bang A TT
1 2 3 4 5
Ky hieu mlu Kl (ven sOng)
K2 (cich sOng 50 m, ngupc gid) K3 (cich sOng 150 m, ngupc gio) K4 (cich sOng 50 m, xuOi gid) K5 (cich sOng 200 m, xuOi gid)
Ket qua (|ig/m^) 78 42
<30 47 39 Ven sdng m i c dd d nhilm mtti rit nang,
him lupng HjS trong khdng khi vttng ven sdng l i 78 fig/m' trong dilu kien do d diu hudng gid, dilu kidn binh thudng. Gii tri H2S tai vi tri cich xa bd sdng 50 m xip xi dat m i c bang ngudng gidi ban cho phep theo quy chuin ky thudt qude gia vl mdt sd B A N G 4: Kit qua do H2S trong khdng
chit ddc hai ttong khdng khf xung quanh QCVN 06:2008/BTNMT la 42 M.g/m' Tai vj trf cich xa bd sdng 150 m ndng dd HjS giam xudng dudi 30 |xg/m\ Trong dilu kidn xudi theo hudng gid thi d khoang cich 50 m ttt bd sdng ham lupng HjS la 47 Hg/m', din 200 m ham lupng cdn 39 ng/m'.
khf (TB 1 gid) khu din cu ven sdng Td Lich TT
/ 2 3 4 5
KHM Kl K2 K3 K4 K5
Mdta
ThOn Van, cdng Nha may Det nhudm Trung Thu, cich sdng 50 m
Bing B, cich sdng 7 m
Bing A, cdng ling, each sdng 50 m Bing A, cich sdng 200 m, khu dan cu Thdn Trung, cdng Tradng THCS Hiuong Liet
Tpa dp 20" 57' 32"
105° 48'58"
20" 57' 22"
105" 49' 35"
20° 57' 48"
105° 49'09"
20"57'45"
105°49'12"
20° 5 7 ' 5 1 "
105° 49' 06"
Ket qua (^g/m^) 58 88 82 64 65
m
Nghiin dm Phit tri&i bin vflng, si 1(34) -Thing 3/2012NguySn Thi Bich Nguydt - Anh hudng cda nUdc sdng Td Uch ddn mdi trudng ...
Nhin xdt: Khu vyc ven sdng c6 mic dd d nhilm khdng khi H2S cao gip 2 lin Tidu chuin cho phep (TCCP) hidn hinh. Khu vyc ttirdc khi gid thdi qua mit sdng tii 50-150 m mic d nhilm ngang mic cho phep cia TCVN. Theo hudng gid din 200 m mdi tradng khdng khf vin bi 6 nhilm khf HjS.
3. Sdng Td Lich anh hudng den sic khoe ngudi din
3.1. Anh hudng nu&c song Td Lich den sOc khoe ngudi ddn canh tdc ndng nghiip ven sdng.
Kiln thic cua ndng din vl cic tic ddng cua nudc sdng din sic khoe dupc thi bidn d mdt sd khia canh sau diy:
* Tilp xuc vdi nudc sdng thudng xuydn se mic cic bdnh ngoii da do ttong nudc sdng cd nhilu chit bin giy benh.
* Do nudc sdng dupc bom vao lim nudc tudi ndn cd miu den, mtti thdi nen ngudi din lim viec tten ddng rudng rau cam thiy rit khd thd vi kha ning giy benh ngoai da cao.
* Nudc sdng khi bom ien cd bpt miu hdng cd mtti thdi ndng nic thi ichi tilp xic se giy hai cho da tay chin.
* Nudc sdng mdi bom len thi cd kha ning giy benh cao hon l i nudc sdng da dl liu ngay ttong cic thia rudng.
Theo dilu tta phdng vin ngudi din lim ndng nghidp d diy cd tilp xuc vdi nudc sdng thudng xuit hidn nhihig bdnh nhu sau:
-I- Min ngia, sung ngoai da, mung mu.
•I- Thdi mdng tay chin.
+ Mtti nudc cua sdng giy cho ngudi din cam giic khd thd.
+ Benh phu khoa.
-I- Bdnh vl mat, bdnh vl dudng hd hip, bdnh dudng rudt.
Trong khi di dilu tta vi hdi ngudi din cua tiidn Trung (xa Phucmg Liet) cho tiiiy nudc thai cua cic hd gia dinh cd nhi thue trp thi hiu hl^t nudc thai sinh hoat dlu dd ra cdng chung cua ca thdn sau dd nudc thai niy mdt phin di vio cic ao ci trong thdn vi phin cdn
Nghiin ciru Phit triin bin vOng, $61(34)- Thing 3/2012
lai thi ra cinh ddng va dupc thai ra sdng. Vao mtta khd ttam bom cua thdn bom nudc sdng vao s i dung cho muc dfch ndng nghidp.
Qua kit qua dilu tta ngudi din tfidn Trang cho thiy gin nhu 100% ngudi din khi tilp xuc vdi nudc sdng dlu bi min ngia d tay va chin vdi mic anh hudng nang nhe khic nhau.
Qua phdng vin tryc tilp vdi ngudi din vi quan sit thyc td cho thiy ttong nhttng nim gin diy ty le ngudi din tilp xic tryc tilp vdi nudc thai bi cic benh ngoai da, benh dudng rudt, bdnh vl dudng hd hip va cic bdnh khic cd xu hudng ting ien.
Nhttng anh hudng ddi vdi ngudi din khi tilp xuc vdi nudc sdng bilu hidn la nhttng ndt ttdn dd d Idng bin tay, da bi bong, chin cd mun nudc, ngia. Nhttng ngudi thudng xuyen tilp xuc thi mdng tay bi nit, thdi mdng, hoic bi ioet nhic d mdng chan.
Trong thdn Trung cd tdi 80% cic hd din cd s i dung nudc gilng khoan, khoi dl an udng, ndn ngudi din thudng bi nhilm giun dfla (Theo kit qud eua trung tdm y tecua xd diiu tra 110 ngudi ddn tai xd). Trong dd ti le tre em vi phu ntt mic benh cao.
Nhu ta bilt nudc thai vi cin bun cua nudc sdng cd chia cic loai vi khuin giy bdnh, tring giun sin. Ude tfnh cd khoang 7.000 vi khuin SahnoneUa, 6.000-7.000 vi khuin shigella va 1.000 vi khuin Vibrio cholera trong 1 Ift nudc thai, cic loai virat. Ngoai ra ttong nudc sdng cdn chia nhilu cic loai tring giun sin, cic loai tting giun sin niy cd thi tdn tai din 1,5 nim vi thudng giy ra cic hiu qua nghiem ttpng.
Ngudn nudc d nhilm cflng Ii noi phit triln cua cic loai sinh vit mang mim benh nhu radi mudi, thudng giy ra cic bdnh ia chay, kilt Ij, thuong ban, sdt ret... ttong dd tre em vi phu ntt la nhttng ngudi dl mic hon ca.
Ngoai ra benh dau mit hdt, benh ngoai da cung khi phd biln.
3.2. Anh hudng cua khi H^S den sdc khoe cua ngudi ddn ven sdng.
Chit lupng mdi tmdng khf cua cic khu din
m
hudng rit ldn din sic khde vi hoat ddng cua ho.
NguySn Thi Bich Nguydt - Anh hudng cda nudc sdng Td Lich den mdi trudng
cu sdng ven sdng bi anh hudng bdi nudc sdng Td Ljch chu yeu la do khf HjS giy ra.
Theo kit qua dilu tra khao sit vi thim do Chit Iupng khdng khf theo sy dinh gii cua y kiln cua ngudi din noi diy khf H2S anh ngudi din sdng ven sdng (bang 5)
BANG 5: Anh hudng cua nude sdng Td Lich din sic khoe ngudi din
Dinh gii
Danh gii dinh tirih chit lupng ninSc sOng Dinh gii mifcdO ptt&t thai khf HjS
Tic dOng ciia nu6c sOng ddi khOng khi xung quanh Tic dOng de'n sue khoe con ngudi
Nu6c song Td Lich Miu sic cua niiliic sdng
T\rong ddi trong 0 ntiiSm nhe
feed mii hoi.
lucmg H2S (Mt thai ft
feanh hucng
Miu h ^ nhat 6 nhiem Uiing binhvi dong nudc ttt hdY&i Sdpha loang MilihOi doHzS ciing giam nhung phu thuOc vao thdi tifit Tic d6og nhe
Mau den
dnhi^m ning.cd mit cua nudccu vinudc thai mdi viosOng
MMhOi thdi do khiH^S giy nen tit manh
Tic dpng manhd€h ngudi canhtic nOng nghiep vi nhihig hp din sdng ven sdng TOlich
Cdbpt tiing
6 nhilm rit nang cdmat cua nudc xi I^dng, chit giat tiy...
MilihOi thdi do khiH^S giy nen rSitmanh
TicdOng rit manh deh khOng kfaixung quanh vi siic khoe ciia con ngudi
Dieu kien thdi tiet Trdi mua,
gii nhe
dnhiSm nhe
N&igdO HjSthip dolupng ch&hihi CO bi ling dpng, I^u thupe vao thditi^
Tic dOng khOng thudng xuyen
Trdi ning to, ndi ndm..
6 nhiem ning
N ^ g d p HzScao dolupng chithihi CO nhilu, phu thudc vao thdi tiStdo trdin&n TicdOng manh
Dong chay (hudng vi lim lupng) Nudc chay vl hdYenScr
6 nhi€m nang, nudc thai ciia thanh phd vi nudc cud sdng dupc bom cuSngbiic
Trudng hpp cd miuden\il thCTi
Tic dOng manh
Hiu het ngudi din sdng ven sOng khi ma ngii thiy miii hOi thdi cua nudc sdng dlu bi nhttc diu va bi khd thd. NhSng luc nhu th^ nidi va mudi lit nhilu
Chay til Hd vIsOng
6 nhilm tnmgbinh, hdYenS61a hd dilu hoi (tip trung nudc thai vi nudc mua)
Cdsutic dOng nen nu6cthaicd mau vang nhat viit thdi
Tic dOng via [Mi
( Nguon: Trich theo bdo edo cua Dudn Ndng cao dieu kien ve sinh mdi trudng ciia cdc thdn ven sdng, VESDI, 2008)
m
NgNin cdu Phit triin bin vitng, si 1 (34) - VAig 3/2012NguySn Thj Bich Nguydt - Anh hudng cda nudc sdng Td Lich den mdi trudng ...
4. Tinh toin lupng khi HjS dupc sinh ra ttt dupc Iiy phin tich lam co sd tfnh toan kha nang sdng Td Lich phit sinh khf HjS tii nudc sdng Td Lich.
Chit lupng nudc sdng khu vyc ha ngudn - V| trf cic dilm Iiy miu nudc sdng:
thdn Bang B, xa Thanh Lidt, Thanh Tri, Hi Ndi 20''57'24"N, 105''49'29"E .
B A N G 6: Thdng sd dieu kien tu nhien khi lay miu Ngiy
24/3/2009 25/3/2009
Ky hieu miu NSl NS2
Mua KhOng
Cd
Lupng miy
6/8 8/8
Nhiet dd
e'c)'
252 23,8
Dp am (%) 74,8 99,0
ap suit (mbar) 1.014,4 1.011,5
Hudng gid DOng bic
Lang gid
Tdc dd gio (m/s)
1,0
B A N G 7: Ket qua phin tich miu nude sdng khu vyc thdn Bing B
Ten miu NSl NS2
Ngay Iiy miu 24/3/2009 25/3/2009
S mg/l
18,6 5,32
BOD5 mg/l
172 13,9
COD mg/l
19,6 152
DO mg/l
1,6 2
pH
7,57 7,16
Gii tri ndng dd hydro sunfua hda tan trong nudc sdng Td Lich tuong duong dao ddng ttt 5,32 (ngiy cd mua) din 18,6 g S/m' (ngiy khdng mua) cao han m i c ndng dd trung binh trong cic hd thdng thoit nudc thai sinh boat (theo Thorkild Hvitved- Jacobsen) ttt 2,6 lin (ngiy cd mua) din 9,3 lin (ngiy khdng mua) v i cin phai c h i y din cic tic ddng cd hai do phit thai cua hydro sunfua giy ra.
Gii tri pH d vttng ha luu sdng Td Lich (thdn Bing B) dao ddng trong khoang ttt 7,16 - 7,57 dat quy chuin ky thuit qude gia vl chit Iupng nudc mit QCVN 08:2008/BTNMT, cdt A2: 6 - 8,5 va chit Iupng nudc dinh cho thuy lpi TCVN 6773 - 2000. d pH tuong ddi dn dinh nhu viy, su chuyin hda nim trong t h i cin bing gitta c i c ion S^', HS" v i khi H2S, thyc t l , trong nudc tdn tai dang chu ylu la HS', H2S v i mdt phin sunphat hda tan. Ndu cd sy x i o trdn b l mit, H2S dupc giai phdng kiidi pha long v i chuyin sang pha khf va cic ion S^", HS chuyin hda thinh H2S
thay thi, gitt vttng t h i cin bing trong nudc. Diy cflng la khoang gii tri pH ma khf H2S duoc cho la sinh ra nhilu nhit.
Chl sd BOD5 nam trong gidi ban QCVN 08:2008/BTNMT, cdt B2 < 25 mg/l, chi sd COD nam trong gidi han ddi vdi cdt Bl
< 30 mg/l, tuy nhidn COD cao ching td trong nudc chia nhilu chit httu co. Ty sd BOD5/COD xip XI 0,9 l i khi Idn, dilu dd ndi ldn rang chit httu co cd trong nudc sdng Td Lich chu ylu thudc nhdm d l phin giai bdi qui trinh sinh hpc. Ty 16 nay cing cao, kha ning hinh thinh khi H2S cang Idn, qui trinh k h i ehilm uu t h i do viy chl sd DO giam. Ngiy t h i hai, lupng khf H2S sinh ra ft hon ban la do trdi mua, chi sd DO cao hon, cdn BOD va COD giam di lam giam kha ning sinh khi H2S.
Cd nhilu phuong phip ude tfnh Iupng khi H2S cd thi phit thai ttt nudc thai tren he thdng thoit nudc, trong dd phuang phip md hinh hda va ude tfnh lupng khi HjS phit thai (Theo Chaturong Yongsiri).
Nghiin cCru Phit triin bin vitng, si 1 (34) - Thing 3/2012
SI
NguySn Thi Bich Nguydt - Anh hudng cda nudc sdng T6 Uch din mdl trudng .
B A N G 8: Tinh toan phat thai khi HjS t& sdng T6 Lich Thdng sd
RH2S
RH2S RH2S
Rms
RH2S RH2S
Donvi gS/m'/h 20°C
25,2°C kg S/ngiy kg S/ngay tSa S/ngiy Tin quy ddi SOi/nim Tin quy ddi SOj/nam
Mua 0,053 0,059 822,5 916,3 0,916 198,1
Khdng mua 0,184 0205 2.872,7 3.200,5 3,201 1.5042 1.702,3
Phit thai trong ngiy cd mua la RH2S = 0,916 tin S/ngiy d 25,2''C, phit thai trong ngiy khdng mua Ii 3,201 tin S/ngiy d 25,2''C. Sd ngay mua ttung binh la 115 ngiy/nam, nhu viy tdng lucmg phit thai HjS ttt sdng Td Lich quy ddi tuong duong vdi lupng SO2 Ii 1.702,3 tih/nim.
So sinh vdi bio cio tdng kit dl tii nhinh cua dl tii cip Nhi nudc KC 08.02 "Nghidn ciu xiy dyng quy hoach mdi tmdng khdng khf phuc vu phit triln KT-XH vung DBSH giai doan 2001 2010 (theo Duong Hdng Son), Iupng SO2 phit thai cdng nghidp ttung binh cua thanh phd H i Ndi nhu sau (bang 9):
B A N G 9. Lupng phat thai tuong duong vdi SO2 cua cdng nghidp TP Ha Ndi theo nam vi theo didn tich
Nam 1998 1999 2000 2001 2002 TB
Phat thai tuong duong (tin SOj/nam) 72.559,7
50.759,7 83.167,0 83.532,0 106.9802 79.399,7
Phat thai qui ra tin SOj/kmVnim 74,38
52,03 8526 85,63 109,6 81,38 Nhu vay, Iupng phit thai H2S dupc quy
ddi ra S62 la 1.702,3 tin SOz/nim tuong ducmg vdi 2,14% Iupng SO2 phit thai cdng nghidp trung binh cua thanh phd H i Ndi trong giai doan 1998-2002.
Dien tfch mat thoing sdng Td Lich chi xip xi 13,5 km x 0,035 km = 0,4725 km^
Do viy cudng dd phit thai H2S ttt sdng Td Ljch quy ddi ra SO2 theo don vi didn tfch se rit Idn, tuong duong vdi 3.602,8 tin SOj/nim/km^, gip 44,3 lin so vdi cudng dd phit thai SO2 trung binh ttt ngudn cdng nghiep cua thanh phd H i Ndi.
M i c phit thai cua 1 td miy cua nha may nhiet dien ddt than s i dung cdng nghd Id sdi tuin hoan (Circulating Fluidized Bed) cdng suit 55MW, cd m i c phit thai theo QCVN 19:2009/BTNMT Ii dudi 500 mg SOifNm^ (trong dilu kidn chuin), vdi luu Iupng phit thai khdi l i 100 mVs va thdi gian vin hanh thuong mai 6.500 gid/nim ude tinh la 1.170 tin S02/nim (theo Stefan Loehr, Christian Barczus). Nhu vay lupng phit thai H2S ttt sdng Td Ljch quy ddi tuong duong SO2 tin/nim cao gip 1,46 lin so vdi m i c phit thai SO2 cua 1 td miy cua
m
Nghien citu Phit tUn bin vitng, si 1 (34) - Thing 3/2012NguySn Thi Bich Nguydt - Anh hudng cda nudc sdng Td Lich den mdi trudng nhi miy nhidt dien ddt than cd cdng suit
55 MW.
Ndng dd H2S trong nudc thai trdn sdng Td Lich l i rit cao, Iupng phit thai khf H2S ttt sdng Td Lich la rit ldn, va cin cd nhttng bidn phap giam thilu kha ning giy 6 nhilm nay.
5. Kit luin
1. Chit lupng nudc sdng Td Lich rit kim, chi sd BOD5 vi COD cao, vupt qui quy chuin cho phep cua Bd Tii nguyen Mdi tmdng rit nhilu, chi sd DO thip dudi mic cho phep giy ra d nhilm chit httu co va vi sinh vit. Mdi tmdng nudc sdng ngay cang ttd ndn d nhilm ttim trpng do han ciil luu tiidng ddng chay bl mat.,
2. Do mdi trudng nudc chia nhilu chit httu CO, ylm khf (DO thip) ndn kha ning smh khf HjS rit ldn, da lam anh hudng din chit lupng nudc sdng, chit lupng khdng khf khu vyc ven sdng ndi chung vi khu vyc thdn Bang B ndi ridng. Dilu niy giy anh hudng ldn tdi sic khde ngudi din sinh sdng, giy ra nhflng benh phu khoa, benh ngoii da, dau mat, hd hip, dudng rudt...
3. Mdi ttudng khdng khf ven sdng Td Ljch bi d nhilm H2S vdi ham lupng cao gip 2 lin TCVN 5938-2005 (80 ^g/m'), ttong pham vi cich sdng 200 m mdi ttudng vin bi d nhilm nlu tfnh xudi theo hudng gid.
4. Lupng phit thai H2S dupc quy ddi ra SO2 l i 1.702,3 tin S02/nim tuong duong vdi 2,14% Iupng S02phat thai cdng nghidp ttung binh nim cua thanh phd Ha N(5i, v i gip 1,46 so vdi mic phit thai SO2 cua 1 td miy cua nha miy nhidt dien dd't than (Id CFB) cd cdng suit 55 MW. Cudng dd phit thai HjS ttt sdng Td Lich quy ddi ra SOj theo don vi dien tich rit Idn, tuong duong vdi 3.602,8 tin SOJn&m/km^ so vdi m i c dd phit thai SO2 ttt
ngudn cdng nghiep cua thinh phd Ha Ndi, trung binh chi l i 81,38 tin SOj/nim/kml
5. Cic bidn phip giam thilu kha nang smh khf HjS bad gdm quan Iy vi ky thuat.
Trong dd, bien phip nao vet, cai tao sdng, ke bd lam dudiig hai bdn sdng cin dupc dua vio thyc hien sdm. Ben canh dd bien phip cai tao nudc sdng bang cich pha loang ndng dd ttt cic hd chia hoic ddng sdng khic li rit quan trpng, cin dupc luu tim vi dua vio thyc hidn cang sdm cang tdt dl cd thi cai thiin mdi tmdng nudc sdng Td Lich hien nay./.
TAI LigU THAM KHAO
1. Lehua-Zhang, et aii (2008). Chemical and biological technologies for hydrogen, sulfide emission control in sewer systems: A review, Water Research, Volume 42, page 1-12.
2. Chaturong Yongsiri, et all. It^uence of wastewater constituents on Hydrogen sulfide emission in sewer networks, Journal of Environmental Engineering. Vol 131, No 12,1676-1683.
3. Thorkild Hvitved-Jacobsen (2002). Sewer processes: Microbial and Microbial and Chemical Process Engineering of Sewer Networks. CRC Press LLC, Horida 33431.
4. Duong Hdng Son (2003). Nghien cdu xdy dung quy hoach mdi trudng khdng khi vUng DBSH giai dogn 2001 - 2010. Dl tii cip Nha nudc KC-08-02:
Nghien ciiu xiy dung quy hoach mOi trudng khOng khi phuc vu phit triln KT-XH vimg DBSH giai doan 2001 -2010.
5. Stefan Loehr, Oiristian Barczus, Viktor Scherer, Frank Kluger and Joachim Seeber (2005).
Pilot Plant Combustion Tests of Low-Volatile and High-Sulphur Coal for the 55 MWel CFBC Cao Ngan Power Plant. Vietnam. The 18th International Conference on Fluidized Bed Combustion (FBC2005), May 22-25,2005 , Toronto, Ontario, Canada.
Nghiin cdu Phit triin bin vOng, si 1 (34) - Thing 3/2012
