Thuc tieh - Kinh nghiem
Xuf ly nirdc bang vat lieu Nano
• v / cd nudc ddng trong
^ r msinh hogt phue vu cugc M.-^ sdng hdng ngdy, ngudi
ddn xd Cao Duang, huyen Thanh Oai - Hd Ndi ngodi viec su dung nu&c mua, vdn phdi diing nguon nu&c td gieng khoan. Nhung dd nhieu ndm nay nguon nu&c gieng khoan nai ddy dd bi d nhiem, ddc Met la nong do asen dd a mdc ddng bdo ddng.
Sdng chung vdi d nhiem Vao nhung nam 2000, ne'u khdng cd doan khao sat ciia d c ca quan chQc nang vl kilm tra tinh trang d nhiim ngudn nudc trdn dia ban thi ngudi dan noi day khdng bidi ring minh vln dang sQ dung ngudn nudc d nhiim d l sinh boat.
Nhiing huyen cd ngudn nudc ngim nhiim asen nang nhit la Qng Hda, Qudc Oai, Thanh Oai... Trong dd, cd xa Cao Duong cua huyen Thanh Oai la dia phuong bi nhiim asen nang nhat.
Ong Chu van Chung, Phd Chu tieh UBND xa cho bid't: Toan xa hien cd 2.256 hg dan vdi gin 10.000 nhan khau. Vi each xa trung tam thanh phd ndn ngudi dan trong xa thudng sQ dung nudc gidng khoan dl dung trong sinh boat, cdn nudc d l ud'ng thi mdi nhl diu cd mdt b l nudc mua. Tuy nhidn, lugng nudc nay ra't ban chd' vi phu thudc nhilu vao thdi tidi.
Ben canh dd, ngudn nudc ngam ngay cang bi d nhiim nghidm
trgng, trong dd nhidm sit, man gan... dac bidt, la nhiim asen.
Khao sat vl tinh trang d nhidm ngudn nudc ngim tai dia phuong vio nam 2003 cua d c co quan chQc nang cho tha'y, cd tdi 91,3%
d c mlu nudc dugc Iiy trong d c gidng khoan d day bi nhiim asen vdi ndng do xorgt qua mQc cho phep tQ 0,05- 0,08%. Mac du, d c gieng d day dugc khoan vdi do sau tQ 50- 70 m ma ngudn nudc cung khdng dam bao, sQc khde cua ngudi dan trong xa dang bi de dga...
Ngudn nudc ngim bi d nhiim da anh hudng nghidm trgng tdi cugc sd'ng cua ngudi dan dia phuong, nhilu ngudi khdng ydn tam sQc khde cua minh khi hang ngay hg vln phii sQ dung ngudn
Xie Iy nifdc thdi nano epc.
nudc. Anh Nguyin Dinh Van d thdn Mgc Xa, xa Cao Ducmg cho bid't, nam 1999, gia dinh cd khoan mgt cli gid'ng vdi muc dfch lay nudc d l phue vu cugc sdng sinh boat hang ngay. Mudn cd ngudn nudc sach anh da cho khoan sau tdi 60m. Khi mdi dd ra chau, nudc trong vit, mat lanh, ai nay diu mQng vi da cd nudc sach d l dung.
Nhung nilm vui ngin ching tay gang, chi sau khoang 15 phut, nudc trong chau tQ trong vit chuyin sang cd m l u nhu nudc vo gao, trdn b l mat cd vang, mui rit tanh khdng sao sQ dung dugc. Dugc mgi ngudi hudng din, anh da Iam mgt bl Igc gdm cat, sdi nhung chat lugng nudc vln khdng dugc cli thidn la bao. Dac bidt, nudc da duac loc
Tdi nguyen yd Mdi trudng | Ky 2-Thang 3/2011 3Q
nhung khi sQ dung trong smh boat nhu tim, giat da xuat hidn ngQa, da min dd. Ban than anh Van nhilu lln rQa mat bing ngudn nudc nay da tha'y thi luc minh bi giam rd ret.
Kit luan cua cle co quan chQc nang sau khi lay mlu cho thiy, ngudn nudc ma gia dinh anh sQ dung da bi nhiim asen la 0,25 %, vugt qua tieu chuln cho phep cua Bd Y te.
Dua cdng nghe nano vao xir ly nudc nhiem asen
Mdi day, dugc su hd trg cua Vidn Nudc, Tudi tidu va Mdi trudng (thudc Vidn Khoa hgc Thuy lgi Viet Nam - Bd NN&PTNT) da triln khai thf dilm md hinh xQ ly nude nhiim asen bing thidi bi sQ dung vat lieu nano tai trudng mim non xa Cao Duong, dilm trudng m i m non Thi Van vdi cdng suit tQ 350-400 1ft nudc/gid va thid't bi lip tai hd gia dinh anh Nguyin Dinh van cd edng suit 80 1ft nudc/ gid.
Kdi qua that bit ngd, ngudn nudc sau khi dugc xu ly bing vat lieu nano ndng do asen da giam dang kl, da dat tieu chuln cho phep cua Bd Y te. Cu thi: Phan tfch nude chua qua xu ly ham lugng asen la 0,148%, sau khi xQ ly nudc ham lugng asen chi cdn 0,002%, kilm tra lln 2 sau khi lge la 0,008% va kilm tra lln 3 thi ham lugmg asen chi cdn 0,01%
(tidu chuan cho phep cua Bg Y td' la 0,01%). ChQng kid'n su "thin ky" cua thidi bi Igc nudc bing vat lieu nano, ba Nguyin Thi Lan, Phd Hidu trudng Trudng Mim non xa Cao Duong khdng giau dugc su vui mQng cho biei, tQ trudc tdi nay ngudn nudc ma nha trudng su dung dl nlu an hang ngly cho gin
200 chau hoan toan phu thudc vao nudc trdi. CQ h i khi trdi cd mua, cd trd nha trudng Iai thay nhau hQng, dung vao mdt b l chQa khoang 8m3 nude. Nhung vdi didn tfch be nhu vay nudc chi du dung cho khoang 7 thing, 5 thang cdn lai d c cd phai vao n h l dan quanh vung xin nude vl nlu an cho cac chiu. Xin nudc la mdt chuydn, cdn vide quan tam hem cua giio vidn d day la tQ chd ngudn nudc ngam khdng dam bao vd sinh ndn nhilu phu huynh hgc sinh khdng yen tam vl sQc khde cua con em minh. Cai dugc ldn nhat 11 tQ day sQc khde cua cd, trd cua nha trudng dugc dam bao, phu huynh hgc sinh cd thi ydn tam vdi ngudn nudc sach m l nha trudng dung d l nlu an cho d c chau. Mong mud'n cua nha trudng la tdi day trudng md them ldp (khoang 100 chau) thi nhu d u sQ dung nudc se tang ldn, do nha trudng mong mudn cd them mdt may Igc nua d l cd trd nha trudng ydn tam ban trong vide day va hgc... Hay hd gia dinh nha anh v a n cung vay, tQ khi dugc hd trg mdt thidi bi lge nano vdi cdng suit 80 Ift/gid, sQc khde mgi thanh vidn trong gia dinh duge cai thien rd ret.
SQ dung vat lieu nano trong xQ Iy ngudn nudc nhiim asen d nude ta la diiu rit mdi me. Ong Trin Hung, d n bd thudc Vidn Nudc, Tudi tieu va Mdi trudng - ngudi true tie'p triln khai du an xQ ly nudc bang edng nghe nano d xa Cao Duong cho ring, hieu qua lge nudc cua thiet bi nay II khdng thi phu nhan. Cud'i the' ky 20, cdng nghd nano phat triln manh me, giup tao ra d c vat lieu cd d c hat hay mang cd kfeh thudc vai nano (mgt nano bing mdt phln ty met). Nd'u nbu than boat tfnh (mdt dang cacbon)
dung trong cdng nghidp Igc nude cd kfeh thudc vai micron, thi kfeh thudc hat cua cacbon nano nhd hem hang nghin lln hat than boat tfnh.
Do vay, kha nang Igc nudc cua cac vat lieu nano that tuyet vdi. MQc do lge cua cac may nay rit tinh, Igc dugc cac hat ban nhd vii nano, kha nang khQ khuin rit manh. Hon thd' nQa, du Igc nudc rit sach va cd thi ud'ng ngay nhung nd vln giu nguyen nhiing chat khoang va cac nguydn td vi lugmg d n thidt cho cd thi. Day la mdt trong nhQng uu viet do ban chit cua vat lieu nano mdi cd ma d c chit lieu Igc khic khdng cd dugc.
Hidn nay d nude ta chua cd mdt don vi nio san xuat dugc ldi Igc lam bing vat lieu nano, ma phai nhap tQ nudc ngoai, gia thanh lai dit. Trong khi dd Idi Igc nano 11 phln quan trgng nhit de Igc cae chit sit, vi khuan, dac biet la asen - chit gay anh hudng nghiem trgng tdi sQc khde con ngudi, gay ra d c benh nhu sQng hda ban chan, tay, d c khdi u hay gay benh ung thu....
Theo Cue Quan ly Tai nguyen nudc (Bd TN&MT), trdn ca nudc da cd 1.380 xa cua 40 tinh, thanh phd cd nguy co d nhiim asen trong ngudn nudc ngam, trong dd phd bid'n tai nhilu tinh cua vung ddng bing sdng Hdng, ddng bang sdng Cim Long, va ddng bing ven biin cac tinh Duyen hai miln Trung.
Vide phit triln, san xult thidi bi lge nudc sQ dung vat lieu nano d n cd su chung tay, gdp sQc cua d c ban, nganh, dac bidt la cac doanh nghidp d l ngudi dan nhirng vung cd ngudn nudc bi nhiim asen cd thi ydn tam ban vl sQc khde eua minh khi da cd du nudc sach d l dung.
LE HAI 4 0 Tdi nguyen vd Mdi trudng I Ky 2 - Thang 3/2011
