Nauven Khac Thai Son Tap chi KHOA HOC & CONG NGHE 73(11) 134 139 THU^C TRANG RAG THAI SINH HOAT TAI KHU VU^C KI TUC XA TRUOTVG DAI HOC NONG LAM DAI HOC THAI NGUYEN Nguyen Khac Thai Son'''', Ha Anh Tuan'''',[.]
Nauven Khac Thai Son Tap chi KHOA HOC & CONG NGHE 73(11): 134- 139 THU^C TRANG RAG THAI SINH HOAT TAI KHU VU^C KI TUC XA TRUOTVG DAI HOC NONG LAM - DAI HOC THAI NGUYEN Nguyen Khac Thai Son', Ha Anh Tuan', Dam Thi Ngoc Huyin', Duong Thi Minh Hda', Hoang Ngan Hai', Nguyin Due Himg', Tran Thj Thanh Huong', Le Anh ThSng' , Trirdng Dai hoc Sdng Idm - DH Thai Sguyen 'Dcii hoc Thdi Sguven TOM TAT Thuc trang rac thai sinh boat tai khu v uc ki tuc xa Trudng Dai hgc Ndng lam Thai Nguyen nhu sau: 1- Hang nam Nhii trudng phai chi khoang 50 trieu ddng de thu gom, van chuyln rac thai den noi xu li 2- Cac miia thdi tiet khic thi khdi luong va phan rac thai sinh hoiit khac miia Ddng cd khdi lugng rac thai sinh boat it nhat chi la 73,75 g/ngay/ngudi; nhung ti le rac vd co lai cao nhat, chiem 27.86°-o 3- Cac vi tri ki tiic xa khac thi khdi luong va thiinh ph^n rac thai sinh boat ciing khac nhau, ki tuc xa C cd luong rac thai sinh hoat Idn nhk tdi 101,75 g/ngay/ngudi; nhung ki tiic xa A lai cd ti le rac vd co cao nhat, chiem 28,14 °'o 4- Gidi tinh sinh v ien anh hudng ro ret din khoi lugng va phSn rac thiii sinh boat; lugng rac thai sinh hoat cua mot nam sinh ki 33 g rac'ngay, tuong iing vdi 9,9 kg rac/nam hgc, d"d cd 31,82 % reic vd co: luong riic thai sinh hoiit cua mot mi sinh la 165,2 g rac'ngay, tucmg irng vdi 49,56 kg reic/nam hoc, dd cd 14.23 % rac vd co Til' khda: rac thai, ki tiie xd sinh hoat Trirdng Dgi hgc Ndng ldm Thdi Nguven DAT V A N D E '• ', Trong sinh hocat bang ngay, ngudi da dua vao mdi trudng mdt lugng rac thiii khdng nhd, trung binh 190g rac thai/ngirdi/ngay [1], [2] Vdi Imn 85 trieu ngudi thi lugng rac thiii sinh boat cua diin cu cii nirdc la khoang 16.000 tcin/ngay Vi vay nghien cuu thuc trang va xir li lugng rac thai dl dam bao an tOcin cho mdi trudng sdng het sire Cein thill Hien loan qudc cd khocing 1.6 trieu sinh vien sd dd cd khoiing 30% song cac ki tuc xa Nhu vay, vdi gan nira trieu sinh vien thi hrgng chat thai d khu vuc ki luc xii ki rat Idn, cinh huong khdng nho din mdi trudniz sdng va hgc tcip cua sinh vien Tuy nhien, den chua cd nhfrng nghien ciru dAy du va tOcin dien ve chat thiii sinh boat a ki tiic xa sinh vien Trudng Dai hgc Ndng Lam Thai Nguyen ihirtTng xuyen cd khoang 5.000 sinh vien tham gia sinh boat khu ki tiic xa eua Tel: 09SS ''I'^.622: Email:nklhaison 134 dvahoo.com Nhei trudng, lugng rac thai ciia sinh v ien la r^t nhieu nen da imh hudng khdng nhd tdi mdi tru'dng sdng Trudng [3] D I cd hilu biet day du ve thuc trang khdi lugng, phan rac thai sinh hoeit cua sinh vien d cac ki tuc xa Nha trudng lam ca sa cho viec nghien ciru Ceic bien phap xir li rac thai tai cho, chirng tdi dci tien hanh nghien ciru de tai "Thi/c trgng rdc thai sinh hoat tgi khu vyc ki lite xd Trirdng Dgi hgc Ndng ldm - DH Thdi Nguyen " Nghien ciru nhcim dcinh gia dugc thuc trcang rac thai sinh boat lai ki tuc xa Trudng Dai hgc Ndng lam Thai Nguyen ve khtii lugng va phan Cling nhu cac ylu td anh hudng din nd, linn ca sa de xueit hirang Vei bien phcip xir li iihiim nang cao chiit lugng mdi trudng song sinh vien ki tuc Xci cd y ngliTa tlurc lien DOI TU'ONG N Q I DUNG v A PHUONG P H A P NGHIEN CUU Doi tu'ong nghien ciiu: Nghien ciru tap trung vao sd lugng va theinh phcin rac thcii sinh hoat tai ki tuc xa sinh v ien Trudng Dai hgc Ndng lam - DH Thai Nguyen Nguyen Khac Thai Son Tap chi KHOA HOC & CONG NGHE No! dung nghien ciiu Nghien ciru gdm ndi dung sau: 1- Danh gia so' bd tinh hinh thu gom va xir li rac thai sinh hoat khu vuc ki tiic xa Trudng Dai hgc Ndng lam - DH Thai Nguyen 2- Nghien cuu anh hudng ciia cac miia tbdi till nam den khdi lugng va thcinb phan rac thai sinh boat tai khu vuc ki tuc xa 3- Nghien cuu iinh hudng ciia vj tri ki tiic xa den khdi hrgng va thanli phan rac thai sinh boat ciia sinh vien 4- Nghien ciru anh hirdng eua gidi tinh sinh vien den khdi lugng vii phan reic thai sinh boat tai khu vuc ki tuc xa Phuong phap nghien ciiu Nghien ciru sir dung phuong phap dieu tra mau dien hinh cu the nhu sau: - Chgn d mdi khu vuc ki tiic (A, B, C) phdng nam va phdng mi de lam man theo doi sudt nam, tinh rieng theo miia Cac phdng chgn lam mau theo ddi phai dam bao yen cau la cd sd ngudi d dn djnh sudt thdi gian theo ddi - Dat d mdi phdng miiu theo ddi thiing dung rac sinh boat: thiing dung rac vd co' I thiing dung rac hfru co; yeu cau sinh vien eiia phdng phan loai rac bd vao thuiig - Phuong phap theo doi rac hfru co': miia he can djnh ki ngay/lan miia ddng ciin djnh ki ngay/liin - Phuo'ng phap theo ddi rac vd co': can djnh ki 10 ngay/lan - Tdng hgp sd lieu, phcin tich ket qua KET QUA vA T H A O L U A N Thue trang ve thu gom va xu' li rac thai sinh boat khu ki tiic xa Tru'dng Dai hoc Nong lam - DH Thai Nguyen Hien Trudng Dtii hgc Ndng kim Thai Nguyen ed khoang 5.000 sinh v ien cu tni tai khu ki tlie xa (ki tue A ki uic B d Tru'dng Vci ki liic C ki khu ngoai cdng Trirdng) Reic ihiii cua sinh vien ti ki tiic xa A dugc tap kel lai mdt bai rac vdi dien lich khoang 30 in" Rac thai sinh boat eua sinh vien ti ki tiic xa B dugc gom liiJ lai be rac nhd dirtTc diit rai rac leTJ dciu Ceic dciy nhii [3] Trong Trirtnig ngoiii 73(1 1): 134- 139 rac thcii cua khu ki Uic xa cdn thiing icic cdng cdng dat de gom rac tai Khu Hieu bd vii nha lam viec cua cac khoa Trong nhirng nam vira qua, Trudng Dai hgc Ndng lam Thcii Nguyen da ki hgp ddng vdi Cdng ti Quan li dd thj Thai Nguyen ve v iec thu gom van chuyen va xir li rac thiii ciia Nha tru'dng Theo dd Cdng ti se vao thu gom rac lan/tuan, sau dd van chuyen den bai rac Tan Cuong, ngoai d TP Thai Nguyen de chdn lap Sd lieu biing cho thay: sd lien ma Nha trudng phai bo de chuyen lugng rac thai sinh boat ciia sinh vien la kha Idn, khoiing gein 50 trieu ddng/nam Khdi lugng phan rac thiii sinh boat lai khu vuc ki tuc xa sinh vien chju sir chi phdi ciia cac miia thai tiet, eua vj tri ki tiic xa Vci ciia gid'j tinh sinh vien Ndi ciich khac ciic miia tbdi tiet khac Ccic vj tri ki tiic xa khac phdng d cua nam sinh va nir sinh cd the diin den khdi lugng Vci phan rac thai sinh boat khiic Chinh vi vay nghien cuu da bd tri cac miiu theo ddi (nhir phiin phuong pliiip nghien eiru da md tii) sir cinh hu'dng eua ea yeu td niiy den khdi lugng Vei thiinh phiin nic thcii sinh hocat eua sinh vien Anh hudng ciia cac miia thoi tiet nam den khoi lu'ong va phan rac thai sinh hoat tai khu vuc ki tiic xa Sd lieu bang cho thciy khdi lugng va phcin rac thai sinh boat tai khu vuc ki tiic xa sinh vien d cac miia tbdi tiet khac nam la khac Vi' khdi hrgng rdc thai: Tdng khdi lugng rac thai sinh boiit trung binh eua sinh vien tai ki tlie xa la 83,44 g/ngciy Trong dd, reic thai sinh boat d mua Thu lit cao nhcit, dat tdi 89,30 g/iigay; thap nhal nam lii lugng rac thiii sinh boat d miia Ddng, chi dat 73,75 g/ngeiy Dieu la thang miia Thu cd nhieu le, vi du: Tet Trung thu (15 thcing am Ijch), ngiiy Phu mi Viet Nam (20 thang 10) Vci ngiiy 09 thang 09 - ngiiy ma tlit} he tre coi la "iigay Dein dng"" Nhirng ngciy le niiy, sinh vien ibutnig id chirc lien hoan "nggf" tcTi phdng Miit khac hang mini viio miia Thu ki miia ddn liin sinh vien nen gia tiing hrgng tieu dimg sinh boat, nd ciing 135 73(1 I): 134- 139 Tap chi KHOA HOC & CONG NGHE Nguyen Khac Thai Son vd • gdp phan Uing them lirong riic thai sinh boiit Diiy la nhfrng nguyen nhein chinh lam gia tiing lirgng reic thai sinh boat tiij khu virc ki tiic xa miia Thu Ngugc kai thang miia Ddng khdng cd nhieu ngciy le ma sinh v ien td cbirc lien hoan tai phdng ngoiii tbdi tiet lanh nen nhu cau an cac loai boa quii giam; day la nguyen nhan lam giam khdi lutTiig reic thcii sinh hocit miia Ddng Ve thdnh phdn rdc thai: Thanh phiin rac thiii sinh bocat cua sinh vien liii khu vuc ki tiic xa trung binh ca nam la 79.57 % rac buu ca vii 20.43 % rac vd ca Trong dd, phan nciy a thdj tiet miia Xuiin tbdi tiet mua He vii tbdi tiet miia Thu khcic khdng nhieu chung dao ddng tir ban 80 den gein 83 % reic lifru ca va tu hail den gein 20 % rac vd co' Rieng d thdi tiet mua Dona, ti le rac hiru co' aJciin xutnig chi cdn lion 72 % va ti le rac vd co tang len din gan 28 % Dieu la d thdi tilt miia Ddng nhu cau ve quii tuoi cua sinh vien giiim, thay vao dd la nhu cau ve dd khd gia Icing, nhu: bcinh keo, mi tdm nen li le reic ihciJ buu co' giam, rac thai vd co' tang Anh huong ciia vj tri ki tiic xa den khoi lu'ong va phan rac thai sinh hoat ciia sinh vien So IJeu bang cho thay d cac khu vuc ki tiic xii khac trirang cung iinh hudng den khdi lugng vii thiinh phcin rac thai sinh boat cua sinh vien - Ve khdi hrgng rdc: Khdi lirgng rac thai sinh hocat trung binh cua sinh vien (ca nam va nir) a ca khu vuc ki tuc xa la 88,63 g/nain Bang 1, Tinh hinh thu gom, van chuvtin riic thai cua Trudng Dai hoc Ndng lam Thai Nguyen trona nam 2005 va 2006 Thang Sd chuven Theina Thana Thana Theina Thina Thana Thana Theina Theina Thcing 10 9 9 9 Thiina 1 Thang 12 Tdng 99 Nam 2005 Ch i phi chuyen (d) Nam 2006 So chuyen 9 9 91 450.870 450.870 450.870 450.870 450.870 450.870 472.348 472.348 472.348 519.574 519.574 519.574 46.748.304 Ch i phi chuyen (d) 500.000 500.000 500.000 500.000 500.000 500.000 550.000 550.000 550.000 550.000 550.000 550.000 47.775.000 (Ngudn: Trirdng Dgi hoc Sdng Ldm Thai Sguyen 2007) Biing 2, Anh huting cua cac miia thdi tiet niiiu den khdi lu'ong vii phcin rac thai sinh hoat tai khu vuc ki tiic Xci ^^-^^^^ Luona I'cic Rac huu CO' Rac vd CO' Khdi luong (giigud'i'ngay) Ti le (%) Xuiin 69.19 80.17 17.11 19,83 86,30 He 69.80 82.70 14,60 17.30 84,40 Thu 73.35 82.14 15,95 17,86 89.30 27.86 73,75 20,43 83,44 Miia ^^" ^^.^ Ddng 53.20 72.14 20,55 Trung binh 65,39 79,57 17,05 136 Tong lu'ong rac (g/ngu'di/ngay) Khdi lugng (g'ngu'd'iiigiiy) Ti \e {%) • Nauven Khac Thiii Son vd t Tcap chi KHOA HOC & CONG NGHE 73(1 34- 139 Biing Anh hirang cua vi tri ki tuc xa den khdi luong vii phan rac thai sinh boat ciia sinh vien "^'^ ^^^ Lugng rac Dia diem ^"^^^ Ki tiic xa A Ki tiic xa B Ki tiic xa C Trung binh Rac hii'u Khdi luong (g/ngudi/ngiiy) 58.35 64.75 CO Ti le (%) 80.10 71,86 78,06 78.72 67,73 76,42 Trong dd ti ki liic xa A va ki tuc xa B gan nhu khdng khac nhau, tuang irng la 81,2 va 82.95 g/ngay Rieng khdi lugng rac d ki tiic xa C Idn hon ban, tdi 101,75/ngay Dieu niiy la ki luc xa A va ki tiic xa B d khudn vien ciia trudng, khdng thuan lien cho sinh vien mua dd mang ve phdng an cdn ki tuc C d gan khu vuc chg nen sinh vien hay mua nhieu thir mang ve phdng an - Ve thdnh phdn rdc: Ti le rac thai vd co' trung binh ciia sinh vien d ca khu vuc ki tiic xa la 23,58 % Khac vdi khdi lugng rac thai, li le reic thiii vd eo' d ki tiic xa B va ki tiic xa C lai gan nhir khdng khac tuong irng ki 21.94 % Vci 21,28 %, kbi dd a ki Uic xii A ti le lai cao hon hiin, tdi 28,14 % Dieu Uciv' ki sinh vien d ki tiic xa A khdng dugc phep nau cin nen hay mua dd iin Seiii vc phdng, vi vay thcii nhieu rac vd co' (lui iiiloii va vd hop kim loai) Anh huong ciia gioi tinh sinh vien den khoi luong va phan rac thai sinh hoat tai khu vuc ki tiic xa Sd lieu bang cho thiiy gidi tinh eiia sinh vien anh liiidng rd ret den khdi lugng va phan reic thai sinh boat tai khu vuc ki tlie Xci - Ve khdi lirang rdc: Khdi lugng rac thiii sinh hoal trung binh ciia cii nam sinh va mi' sinh ki 99 g/ngudi/ngay Trong khi, khdi lugng rac thiii sinh hocit trung binh cua phdng nam sinh chi lei 33 g/ngirdi/ngay thi d phdng nir sinh len tdi 165,2 g/ngirdi/ngay Nhu vay, khdi lugng rac thiii sinh boat ciia phdng mi sinh gap lan so vdi phdng nam sinh Dieu la nfr sinh cd ihdi quen hay iin v iit, hiiy mang theo dd iin mdi kbi tu que nbii den trudng, hay nhan dugc qiui lii dd an cd khach den clioi va cd sa thich hay iiciii mrdng hon nam sinh Ddng lIuTi, nir sinh bay mua com ve mang ve phdng ti de cin nen cd them mdt hrgng riie gdm com, thue iin lliira vii Uii iiilon Naoeii Rac vd CO Khdi lugng Ti le (%) (g/nau'di'ngay) 22,85 28,14 Tdng lugng rac (g/ngud'i/ngay) 81,20 18,20 21,65 21.94 82,95 21.28 20,90 23,58 101,75 88,63 hang thang nir sinh cdn cd them mdt lugng nhd rac thai sinh boat dap irng nhu cau ve sinh Cii nhan - P'e thdnh phdn rdc: Sd lieu bang cho thay ca lugng rac sinh boat hfru co' vii vd co' cua phdng nam sinh deu it hon phdng nir sinh, iilnrng xet ve ti le thi phdng nam sinh cd li le rac vd ca cao va ti le rac hfru co' thap hon Cu the phdng nam sinh cd 31,82 % rac vd CO' va 68.18 % rac buu co' tbi phdng nfr sinh chi cd 14.23 % rac vd co' vii 85.77 % rac hfru CO' Dieu la nam sinh it an udng tai phdng d va neu cd man a gi ve phdng d de an tin cini yeu la dd dii che bien nen hay thai uii nilon.va vo hop kim loai - Tdng lin/ng rdc ndm: Mot neim bgc, sinh vien o tai ki tiic xii 10 thiing, lirong irng vdi 300 Nhir vay, lugng riic thai sinh boat cua mdt nam sinh ki 33g x 300 = 9,9 kg/iiam hgc, gdm 7,75kg riic hfru co' va 3,15 kg rac vd co'; lugng rac thai sinh boat eiia mtii nfr sinh thiii 165,2g x 300 = 49.56 kg/niim hgc gdm 42,51 kg rac huu ea va 7,05 kg rac vd co' Hien toiin Trudng Dai hgc Ndng lam Thai Nguyen ibutTug xuyen cd khoiing 5.000 sinh vien cu tni tai khu vuc ki tiic xii cua Nhii trudng va khu ki Uic xa tir phat ngoiii cdng trudng Trong dd, 60 % la nam, tuong irng vdi 3.000 sinh vien, se cd lugng rac thai sinh boat la gan 30 tan/nam hgc; 40 % la nu, tuo'ng irng vdi 2.000 sinh vien se cd lirgng rac thai sinh boat la gan 100 tan/niim hgc Nhu vay, 5.000 sinh vien cua Nha trudng se ed lugng rac thiii sinh boat 130 tein/neim hgc; trona dd cd bo'n 105 tan ki riic hiru co va aiin 24 tan rac vd co' Vdi each dien giai nhu viiv Iren dja ban tmh Thai Nguyen hien cd khoang 100.000 sinh vien cua Dili hgc Thiii Nguyen Vci ban 20 trudng cao diing trung Ceip Nhu Veiy sd sinh V ien niiy se cd khoang 2.600 tan rac thai sinh hoal/iiiim hoc 137 Nguyen Khac Thai Son vd 73(11): 134- 139 Tap chi KHOA HOC & CONG NGHE Bang Anh hudng ciia gidi tinh sinh vien den khdi lugng va phan rac thai sinh hoat tai khu vuc ki tuc xa Lugng rac Gidi tinh Rac vd CO Rac hii'u co Khdi lugng (g/ngu'di/ngay) Ti le (%) Nam 22,50 68,18 141,70 85,77 Trung binh 82,10 82,85 - De xuat gidi phdp xu li: Tuyen truyen khuyen cao sinh vien phan loai rac tu ngudn, sau dd diing hdn hgp vi sinh vat cd ich (EM) de che bien lugng rac huu co' phan hfru CO' su dung bdn cho cay trdng can Trung tam Thuc hanh thuc nghiem; cdn rac vd co' se phan loai de ban eho tai che va chdn lap Nu' KET LUAN Sau mdt nam nghien ciru, chung tdi thay thuc trang va phan rac thai sinh boat tai khu vuc ki tuc xa Trudng Dai bgc Ndng lam - DH Thai Nguyen nhu sau: 1- Hang nam, Nha trudng phai chi khoang 50 trieu ddng de thu gom, van chuyen rac thai den noi xii' li 2- Cac miia thdi tiet khac tbi khoi lugng va phan rac thiii sinh boat khac nhau, miia Ddng cd khdi lugng rac thai sinh boat it nhat, cbi la 73,75 g/ngay/ngudi; nhirng ti le reic vd CO lai cao nhat, chilm 27,86% 3- Cac vj tri ki tue xa khac thi khoi lugng va phan rac thai sinh boat cung Khdi lugng (g/ngu'di/ngay) Ti le (%) Tong lu'ong rac (g/ngu'6i/ngay) 10,50 31,82 33,00 165,20 14,23 17,00 99,10 17,15 khac nhau, ki tuc xa C cd lugng rac thai sinh boat Idn nhat, tdi 101,75 g/ngay/ngudi; nhung ki tiic xa A lai cd ti le rac vd ca cao nhat, chiem 28,14% 23,50 4- Gidi tinh sinh vien iinh hudng ro ret den khdi lugng va phan rac thai sinh boat; lugng rac thiii sinh boat cua mdt nam sinh la 33 g rac/ngay, tuong u'ng vdi 9.9 kg rac/nain hgc, dd cd 31,82 % rac vd ca; lugng rac thai sinh boat ciia mdt nu' sinh la 165,2 g rac/ngay, tuong dng vdi 49,56 kg rac/nam hgc, dd cd 14,23 % rac vd co' LIEU THAM K H A O [1] Hoang Dii'c Lien, Tdng Nggc Tuan (2003), Ky thitdt vd thiet bi xu ly chcit thai bao ve mdi trirdng, Nxb Ndng nghiep TAI [2] Nguyen Xuan Nguyen (2004), Cong nghe xu ly rdc thdi vd chdt thai ran Nxb Khoa hgc va Ky thuat [3] Trudng Dai hgc Ndng lam - DH Thai Nguyen (2007), Bao cao tdng kit cdng tac ve sinh mdi tru'dng SUMMARY ACTUAL WASTE AT THE HOSTEL AREA IN THAI NGUYEN UNIVERSITY OF AGRICULTURE AND FORESTRY Nguyen Khac Thai Son'*, Ha Anh tuan' Dam Thi Ngoc Huyen', Duong Thi Minh Hoa', Hoang Ngan Hai', Nguyen Due Hung^ Tran Thi Thanh Huong', Le Anh Thang' College of Agriculture and Forestry - TNU 'Thai nguyen University After a year of monitoring, we have the real situation and composition of waste at the hostel area in Thai Nguyen University of Agriculture and Forestry, as follows: Every year, the school must spend about 50 millions to collect and transport the waste to the place of treatment 'Tel: 0988 717.622: Email:nklhaison'iryahoo.com 138 Nguyen Khac Thiii Son vd cs Tap chi KHOA HOC & CONG NGHE 73( 1): 134 - 139 Different seasons, the volume and composition of wastes are different, garbage volume in winter at least, is 73.75 g/day/person, but the ratio of inorganic garbage again the highest, accounting for 27,86 % Different dormitory area, volumes and composition of waste are also different, C hostel has the largest amount of garbage, to 101.75 g/day./person, but A hostel has rate of the highest inorganic waste, accounting for 28.14 % Student affected significantly of the volume and composition of waste: a male student discharges 33 g wastes/day, equivalent to 9.9 kg of wastes year, of which 31.82 % rubbishes Inorganic; a girls student discharges 165.2 g wastes.'day, equivalent to 49.56 kg of wastes.'Vear of which 14.23 % of inorganic wastes Key \vord:ira.v/e, dormitory, living Universily of Agriculture and Forestry Thai Sguyen 139 ... thiii sinh hoal trung binh ciia cii nam sinh va mi'' sinh ki 99 g/ngudi/ngay Trong khi, khdi lugng rac thiii sinh hocit trung binh cua phdng nam sinh chi lei 33 g/ngirdi/ngay thi d phdng nir sinh. .. phai bo de chuyen lugng rac thai sinh boat ciia sinh vien la kha Idn, khoiing gein 50 trieu ddng/nam Khdi lugng phan rac thiii sinh boat lai khu vuc ki tuc xa sinh vien chju sir chi phdi ciia... thcii sinh hocat eua sinh vien Anh hudng ciia cac miia thoi tiet nam den khoi lu''ong va phan rac thai sinh hoat tai khu vuc ki tiic xa Sd lieu bang cho thciy khdi lugng va phcin rac thai sinh