KHOA HOC,
CONG NCHE - CHUYEN CIAONGHIEN CtJU THLfC NGHIEM TRO LUC KHI
O O N G C U A THAN HOAT TINH SO DUA TREN GIA THI NGHIEM BAN CONG NGHIEP
ThS. NGUYfiN
T H A N GLOI, PGS. TS. LE VAN TRINH
Vien N/c KHKT Bao ho Lao dong . PGS. TS. N G U Y f i N
B A T O A ITrudng Dai hoc Xay dung Ha Noi
Tom tat: Nghien ciru tra luc khi dong (TLKD) cua cot than hoat tinh so dira Tra Bac dudng kinh 0,25m, chieu day thay doi tir 0 den 0,9m va van toe thay doi tir 0,2 den 0,5m/s duqc tien hanh tren gia thi nghiem ban cong nghiep. Tir so lieu thuc nghiem, cac tac gia da xac lap duqc cdng thu'c thuc nghiem xac dinh TLKD ciia cot than hoat tinh Tra Bac TBD theo van toe loc va chieu day cot than nhu sau:
AP
— = 915,82V- + 96,057V + 0,1294 vaiR'= 0,9998, s^= 1,41 kG/mVm haysJ(DP/H)^^ = 1,12%. Cae ket qua tinh toan ly thuyet theo 2 cdng thUe Urgun va Serpionova deu cao han nhieu so vdi ket qua nghien cUu thue nghiem. Nguyen nhan la do su khac biet rat Idn giUa hinh dang eua hat dap va tu nhien vdi hat hinh cau ma dua tren dd eac cong thUe duqc xay dung. Su khae biet ve hinh dang dan den su khae biet ve che do thuy luc ciia ddng khi chay bao quanh hat, dan den su khac biet ve TLKD. Tir day cac tac gia khuyen nghi rSng ddi vai than hoat tinh hat dap vd tu nhien nen sir dung cdng thUe thue nghiem de tinh toan TLKD.
Abstract: The studies on hydraulic pressure drop of coconut shell activated carbon TBD column of diameter of 0.25 m with height ranging from 0 to 0.9m and velocity varying from 0.2 to 0.5 m/s, have been carried out on the half-industrial experimental system. On basis of the experimental data, has been built the experimental formula determining the pressure drop of activated carbon column as follows:
\p
— = 915,82r- + 96,057v + 0,1294 with R'= 0.9998, s^= 1.41 kG/mVm orsJ(DP/H)^^^1.12%. The H
pressure drop values theoretically determined by both two formulas Urgun and Serpionova are much higher than values gained from experimental studies. This is caused by the differences in the particle shape between incidentally broken down particles of coconut shell activated carbon TBD and spherical particles, basing on which the two formulas have been built. The differences in the particle shape lead to the differences in the hydraulic pressure drop. From this point, the authors recommend to use the experimental formula to deter- mine the hydraulic pressure drop of activated carbon column with incidentally broken down particles.
cang nhd cang tdt.
I. DAT VAN DE Than hoat tinh so dUa Tra Bac TBD da dupe xuat Trong thiet bj hap phu, hat than hoat tinh dupe dd tu khau sang nhieu nudc tren the gidi, nhung lai chua dupe nhien tao thanh cpt hoac cassete than vdi chieu day xac sir dung rdng rai d trong nude. Mdt trong nhung nguyen djnh theo thiet ke. TLKD cua cdt than (hay cassette than) nhan la thieu co sd du lieu cin thiet eho cdng tac thiet ke la thdng sd quan trpng thir hai eua thiet bj hip phu, nd lien irng dung.
quan tdi tieu hao nang lupng eiia thiet bj. TLKD cang Idn Trong khudn khd bai bao nay, tac gia de cap tdi viec xSy thi tieu hao nang lupng dien cang Idn va ngupe lai, TLKD dung cdng thirc thue nghiem xac djnh TLKD eua than TBD.
cang nhd thi tieu hao nang lupng dien cang nhd. Thiet ke Cdng thirc nay la eo sd du lieu cin thiet cho edng tae thiet ke thidt bj hip phu dupe thue hien sao cho TLKD eiia thiet bj thiet bj hip phu de xir ly d nhiem hoi dung mdi huu co.
5/2009 BAO HO LAO DONG 13
II. PHAN TICH LY THUYET
Trong nhieu tai lieu [3], [4], [5], [6], [7], [8], cdng thife Ergun dupe sir dung nhu la edng thdc da nang de xac djnh TLKD eiia cac loai vat lieu hat hoae vat lieu rdng ed dien tich be mat rieng Idn.
Urgun quan niem cot vat lieu hat nhu la mdt bd dng ngoin ngoeo bat qui t i c len chat va xem xet nd dua tren mdt sd gia thuyet ban d i u nhu sau [6], [7]:
- Trong cdt vat lieu khdng hinh thanh bit ky mdt dng d i n gid uu tien nao va kha nang ehuyen dpng eua khdng khi qua tit ca cac dng la nhu nhau;
- Dudng kinh ciia cdt hip phu Idn hon rat nhieu so vdi dudng kinh eiia hat vat lieu, nen cd the loai bd hieu Ung thanh dng (theo khuyen eao, dudng kinh tdi da ciia hat nhd hon 1/5 dudng kinh eiia cdt hip phu [6]);
- Ddi vdi cae thdng sd van tde, dudng kinh hat va dp rdng cua cot vat lieu, sir dung gia trj trung binh dai dien cho ca khdi vat lieu.
Tren eo sd cac gia thuyet neu tren va mdt loat nghien cUu thue nghiem, Urgun da dua ra cdng thuc nira thue nghiem xac djnh TLKD tinh tren mpt don vj chieu day cdt vatlieuhatnhusau[5],[6], [7], [8]:
AP
H Re ' ; gs\l. (1)
Trong dd:
- AP: TLKD hay tdn thit ap suit ciia cdt vat lieu hat, kG/m^;
- H: Chieu day cdt vat lieu hat, m;
- r^: Khdi lupng rieng eiia khdng khi kg/m^;
- E: Op rdng eiia cdt vat lieu hat;
- g: Gia tde trpng trudng, m/s^;
- d^j,: Dudng kinh hat c i u tuong duong, m (dd la dudng kinh hat c i u ed the tich tuong duong);
- v: Van tde bieu kien eiia ddng khdng khi qua cdt vat lieu hat (van tde Ipc), m/s;
- Re: Chuan sd Reynold, duoe xac dinh bing edng thUe[3],[5],[7],[8]:
Re = din^Pk
( l - 6 - ) / i(2)
Trong dd \x la dp nhdt ddng lue hpc eiia ddng khi, N.s/m^
Bieu thirc trong dau ngoac eiia edng thirc (1) chinh la he sd ma sat ciia cdt vat lieu ap dung vdi 1 < Re < 1000. Sd hang thir nhit la he sd ma sat irng vdi che dp ddng chay Re < 1 va sd hang thir hai la he sd ma sat irng vdi che dp ddng chay Re > 1000. Rd rang, trong trudng hpp thir nhit, dp nhdt ciia chat khi ddng vai trd quan trpng va TLKD eiia cdt vat lieu phu thude nhieu vao chuan sd Reynold. Ngupe
14 BAO HQ LAO DQNG 5/2009
lai, trong trudng hpp thif hai, trd lire eua cdt vat lieu hoan toan khdng phu thude vao chuan sd Reynold.
Mat khac, trong tai lieu [9] ciia Serpionova, TLKD eua cdt vat lieu hat lai dupe xac djnh theo edng thirc nira thuc nghiem nhu sau:
AP _ 3 .^p,{\-s)v-
H 4 <^gd,^ (3)
Trong dd:
- O: He sd hinh dang eiia hat (vdi hinh ciu O = 1; vdi mdt sd hinh dang khae, theo tae gia, ed the tinh trung binh la O = 0,9);
- X: He sd ma sat.
He sd ma sat la ham sd ciia chuan sd Reynold: X = f(Re), trong dd, ehuan sd Re dupe xac djnh theo edng thue:
Re =
2 0 dj^vp3 {\-e)^i . (^)
Tiiy theo che dp chay eua ddng khdng khi, he sd ma sat dupe xac djnh theo cae cdng thuc thuc nghiem sau day:
+ Trudng hpp Re < 50: ^ =
220 Re
, 11,6
+ Trudng hop Re = 50 - 7200: ^ = — ^ 3 7
(5)
(6)
+ Trudng hpp Re > 7200: X = 1,26 (7) Than TBD la loai than hoat tinh sp dUa dap vd tu nhien.
Hat than ed hinh t i m det vdi chieu day eiia tam tuong ddi deu nhau va bing 0,6 mm, cdn kich thude hai canh cdn lai cd the khac nhau. Oe don gian hda ed the chap nhan hat cd hinh tim det vudng vdi kich thude la dxdxa, trong dd, o la chieu day eiia tam va d la kich thude ciia canh.
Cd hat eiia than TBD (kich thude d) dupe xac djnh bing phuong phap sang. Theo phan tich sang, khdi than dupe chia thanh nhieu phan irng vdi dai kich thude khac nhau xac dinh theo kich thude ciia Id sang. Kich thude hat trung binh eiia mdt dai hat nhit djnh bing gia trj trung binh edng eiia kich thude Id sang tren va Id sang dudi [8].
y dm
^ (8)
^ha =
100
Trong dd,
- d; Kich thude trung binh eiia dai hat, mm;
- m; Ty le phin tram trpng lupng eiia dai hat.
Dudng kinh hat c i u tuong duong eiia than TBD dupe xac djnh theo cdng thirc [9]:
6F,
7t
(9)
KHOA H O C , CONG NGHE - CHUYEN GIAO
Hinh 1: Sa do gia thi nghiem TLKD eua than hoat tinh
Khong khi ra
Khong
khi \;i(i
1 - Mieng vao 2-Bo do luu luang
3 - Ong dan khong khi trudc thiet bi 4 - Thiet bi hap phu
5 - Ong dan khong khi sau thiet bi 6 - Quat Ii tam
7 - Vi ap ke so 1 8-Viapkes62
Bang 1: So lieu trdli/c khi dpng cua cot than TBD
v (m/s) 0,0 0,2 0,3 0,4 0,5
AP/H (kG/m^/m) 0,0 55,9 112,9 182,9 278.0
Trong dd V la the tich eua hat than, mm^
V,.
i , - - r B - (10)d^g5
Thay cdng thUe (10) vao edng thirc (9) ta cd:
^ro = dd-ii^S
n
(11)
Rd rang la tren eo sd cac thdng sd vat ly ciia than hoan toan ed the xac djnh dupe TLKD ciia than. Tuy nhien, hat than TBD ed hinh tam det khae xa so vdi hat hinh ciu, nen ket qua tinh toan TLKD theo cae edng thUe tren ed the sai lech nhieu so vdi thuc te.
Cin phai tien hanh xay dung gia thi nghiem va nghien cUu xac djnh TLKD ciia than TBD. Tren eo sd so sanh ket qua tinh toan vdi sd lieu thue nghiem ed the riit ra ket luan ve phuong phap tinh toan trd luc ciia than TBD.
HI. NGHIEN Ciru THUC NGHIEM
IN.1. Muc tieu: Xay dung mdi quan he giUa TLKD vdi van tde Ipc: AP/H = f(v).
111.2. Sd do gia thi nghiem: Sd dd gia thi nghiem dupe bieu didn trong Hinh 1.
Hoat ddng ciia gia thi nghiem dupe md ta nhu sau:
Khdng khi dupe Iiy vao he thd'ng di qua mieng vao (1).
Luu luong eiia ddng khi dupe xac djnh bdi bp do luu lupng (2). Bo do luu lupng kieu vach ngan dupe hieu chinh trudc theo cpt nude chi thi tren vi ap ke MMH - 240 - T sd 1 (7).
Khdng khi tiep tuc theo dng d i n (3) di vao thiet bj hip phu, sau dd theo dng din (5) thoat ra ngoai. Quat Ii tam (6) la ddng luc van ehuyen khdng khi. Van VI dupe sir dung de tao ra cae che dp luu lupng khac nhau. Vi ap ke MMH - 240
- T sd 2 (8) dupe sir dung de xac djnh TLKD ciia cdt than trong thiet bi hap phu (4).
III.3. Npi dung va qui trinh thi nghiem:
Chay he thdng thi nghiem bang khdng khi sach cua phdng thi nghiem. Cac thdng sd vi khi hau ciia khdng khi trong phdng thi nghiem dupe xac djnh bing may do nhiet dp/dp am TESTO - 615 (CHLB
^dc). Thay ddi chieu eao cpt than: 0,2 m; 0,4 m; 0,6 m va 0,9 m. 6 mdi chieu cao cdt than, thay ddi van tde Ipc v = 0,2 m/s; V = 0,3 m/s; v = 0,4 m/s va v = 0,5 m/s bing each quan sat dp ehenh chieu dai cdt chit Idng tren vi ap ke MMH - 240 - T sd 1(7), dieu chinh va djnh vj van VI sao cho dp ehenh chieu dai cdt chit Idng Ung vdi cac gia trj van tde neu tren (hay cac gia trj luu luong tuong Ung eiia he thd'ng).
6 mdi chieu cao cpt than, tien hanh xac dinh TLKD trung binh eiia cpt than Ung vdi cae van tde Ipc da chpn theo dp ehenh chieu dai cpt chit Idng tren vi ap ke MMH - 240 - T sd 2 (8) theo cdng thUe:
APTB = K.AI,3.Y,, (12)
Trong dd:
- AP^g: TLKD trung binh, kG/m^ (hay mm cdt H^G);
- K: hie sd Ung vdi dp nghieng eiia cdt chat Idng (K = sina, trong dd a la gdc nghieng eiia cpt chit Idng so vdi phuong nam ngang);
- Al^^: Op ehenh chieu dai cdt chit Idng trung binh, mm;
- Yj,!^: Ty trpng eiia chit Idng sir dung trong thiet bj. Trong to/dng hpp eu the, chit Idng la nudc vdi ty trpng -{^.^ - 1.
HI. KET QUA VA BAN LUAN
Ket qua xir ly sd lieu dupe trinh bay trong Bang 1.
Tren eo sd sd lieu d Bang 1, xay dung dupe edng thUe thuc nghiem xac dinh tdn thit ap suit theo van tde Ipc va chieu day cdt than nhu sau:
— = 915,82v^
H
-I-96,057v-H 0,1294 (9)(vdi R^= 0,9998, a^= 1,41 kG/mVm hay Q>J(A?IW)^^
r I r\r\r\r\ '^•P ^**'
5/2009 BAO HO LAO DONG 15
Bang 2: Bang tinh toan kich thifdc hat trung binh cua than TBD
Dai kich thude (mm)
<1,5 1,5 -2,5 2,5-3,2 3,2-4,3 4,3-5,5
>5,5
Kich thude hat trung binh ciia dai, d, (mm)
1,5 2 2,85 3,75 4,9 5,5
Ty le % theo trpng lupng, m. (mm)
3,17 2,91 22,69 32,14 37,84 1,25
Kich thude hat trung binh ciia ca khoi than, dTB(mm)
3,9
Bang 3: TLKD tinh theo cong thu'c Urgun, Serpionova va thi/c nghiem[2]
V (m/s) 0,1 0,2 0,3 0,4 0,5
Tinh theo Urgun Re
26,0 51,9 77,9 103,8 129,8
AP
(kG/m^/m) H
62,9 155,1 276,5 427,1 607,1
Tinh theo Serpionova Re
15,6 31,1 46,7 62,3 77,9
X
14,1 7,1 4,7 4,1 3,9
AP
(kG/m^/m) H
98,4 196,7 295,1 460,1 679,8
Theo cong thUc thuc nghiem
(kG/m^/m) 18,9 56,0 111,4 185,1 277,1
= 1,12%)
Dd thj eiia phuong trinh thuc nghiem dupe bieu didn trong Hinh 2.
Tren eo sd ket qua phan tich bang sang [1], sir dung edng thUe (8) xac djnh kich thude hat trung binh eiia than TBD (xem Bang 2).
TU kich thude hat trung binh, xac djnh dudng kinh hat ciu tuong duong eiia than TBD theo edng thUe (11). Vdi d^g= 3,9 mm, 5 = 0,6 mm, ta tinh dupe dudng kinh hat c i u tUdng duong eua than TBD la d^^ = 2,6 mm.
Sau dd, sir dung cac edng thUc tU (1) den (7) tinh toan TLKD eiia eua cdt than TBD, trong dd, ddi vdi edng thuc
Serpionova tam nhan O = 0,9.
Ket qua tinh toan dupe tdng hpp trong Bang 3 [2].
TU ket qua tinh toan d Bang 3 xay dung eac dudng cong TLKD va bieu didn trong Hinh 3 sau day:
Cung gidng nhu ket qua nghien eUu thue nghiem, ket qua tinh toan theo eac edng thirc Urgun va Serpionova deu cho thiy TLKD ciia cpt than TBD ed quan he ham bae hai vdi van tde Ipc (Hinh 3). Tuy nhien, gia tri TLKD eiia cpt than tinh toan theo hai cong thuc deu cao hon nhieu so vdi gia trj thuc nghiem. Neu tinh toan theo cdng thirc Urgun, TLKD tren mdt met chieu day cao hon so vdi gia trj thue nghiem tU 2,19 (d v = 0,5 m/s) den 2,76 lin (d V = 0,2 m/s). Cdn theo cdng thUe Serpionova, TLKD tren mpt met chieu day cdt than eao hon so vdi gia trj thuc nghiem tU 2,45 (d v = 0,5 m/s) den 3,51 lin (d v = 0,2 m/s).
Nguyen nhan eua su ehenh lech nay la do anh hudng cua hinh dang hat den TLKD ciia cdt vat lieu. Su chay bao quanh hat dap vd ngiu nhien eiia ddng khdng khi theo cae hudng khac nhau se khac nhau, trong khi dd, suchay bao quanh hat c i u theo mpi hudng deu nhu nhau. Trong khdi vat lieu hat dap vd ngiu nhien, cac hat vat lieu sap xep ngiu nhien, nen ddng khdng khi chay bao quanh cae hat cung se theo cae hudng khae nhau, d i n den dac tinh khi dpng eiia cpt vat lieu se khae so vdi cdt vat lieu hat ciu dudng kinh tuong duong (the tich bing nhau). Su khac 3
(I 11,1 ( I , : (LI (1.4 11.5 0,6
^ (iiVs) Ghichii.l) theo thuc nghiem: 2) theo Urgun va 3) theo Serpionova(2}
Hinh 2: Sir phu thupe cua TLKD AP/H vao van toe Ipe v Hinh 3: TLKD cua cot than TBD
16 BAO HO LAO DONG 5 2009
KHOA HOC,
CONG NGHE - CHUYEN GIAO
HAi KiniTAT-VfiLn Vi£t iViuu (VOSHA)
TO CHUrc HOI THAO VE VAN DE XA HOI HOA CONG TAG AT-VSLD
N
gay 28/4/2009 tai Ha Npi, Hpi KHKT AT- VSLO Viet Nam da td ehUe mit-tinh ky niem Ngay The gidi ve An toan SUc khoe tai noi lam viec (28/4) va Hpi thao Qud'c gia "Van de xa hdi hoa edng tae AT-VSLD d Viet Nam". Hon 50 dai bieu la cac nha khoa hpc, can bp quan ly, can bd CO, can bp lam cdng tac BHLO da tham du Ld mit-tinh va Hdi thao.Phat bieu khai mac Le mit-tinh, PGS. TS.
Nguydn An Luong - Chu tjch Hpi KHKT AT-VSLO Viet Nam da neu len Ijch sir hinh thanh va y nghla quan trpng eiia Ngay The gidi ve An toan va SUc khoe tai noi lam viee. Ngay The gidi ve an toan va sire khoe tai noi lam viee dupe hinh thanh tU nam 1989 xuit phat tU y tudng eiia nhOng NLO My va Canada mudn danh 1 ngay (28/4 hing nam) de tudng niem nhung ddng nghiep da chet hoac bj thuong tat do tai nan nghe nghiep. Ke tu dd, ngay cang cd them nhieu qud'c gia tren the gidi td ehUe ky niem ngay 28/4. Va den nam 2003, Td ehire Lao ddng Qude te (ILO) da chinh thue ddng y td ehire ky niem hang nam Ngay The gidi ve An toan va SUe khoe tai noi lam viee tren pham vi toan c i u nham thu hut su ehii y ciia mpi td chuc, ea nhan vao cdng tae bao dam AT-VSLO tai noi lam viee.
Hdi thao qude gia "Van de xa hpi hoa cong tac AT- VSLO d Viet Nam" la mdt hoat ddng thiet thue do Hpi KHKT AT-VSLD Viet Nam td ehUe nham ky niem Ngay The gidi ve An toan Sire khoe tai noi lam viec. Tai Hpi thao, eac dai bieu da nghe 4 tham luan va thao luan cac v i n de ve xa hdi hoa ndi chung va xa hpi hoa AT-VSLO; mdi quan he giUa quan ly Nha nude va hoat ddng ciia cae td ehire xa hdi trong qua
ANH:HOIATVSLOVN trinh thue hien xa hpi hoa AT-VSLD; nhan thUe, quan diem va thuc trang tinh hinh xa hdi hoa edng tac AT-VSLO; giai phap thiie day viec xa hpi hoa cdng tae AT-VSLO. Cae dai bieu deu thdng nhit cho ring viec xa hpi hoa hoat dpng AT- VSLO la mpt yeu ciu tat yeu khaeh quan ciia su nghiep phat tnen KT-XH, phii hpp vdi quan diem, chu truong va chinh sach ve xa hdi hoa cua Dang va Nha nudc ta. Trong thdi gian tdi, mudn dat hieu qua eao trong viee cham sde, bao ve sue khoe, tinh mang NLO thi edng tae AT-VSLO phai duoc xa hpi hoa mdt each manh me, toan dien bing cac giai phap ddng bd, thiet thuc, trong dd quan trpng la phai nang cao nhan thue ve edng tac AT-VSLO, xa hpi hoa AT-VSLO va ra soat, bd sung, sira ddi, tien tdi hoan chinh he thdng van ban phap luat ve AT-VSLD.•
MANH KIEN
2 biet ve hinh dang so vdihat hinh c i u cang nhieu dan den su khac biet ve TLKD giua tinh toan va thuc nghiem cang Idn. Neu hat ngiu nhien ed kich thude 3 chieu tuong ddi deu nhau thi su khae biet ve TLKD so vdi hat hinh c i u se khdng nhieu. Trong trudng hop dang xet, hat than TBD cd dang hinh tim vudng vdi kich thude canh 3,9 mm va chieu diy 0,6 mm khae xa ve hinh dang so vdi hat c i u the tich tuong duong, dudng kinh 2,6 mm. Bdi vay, khi sir dung dudng kinh hat c i u the tich tuong duong de tinh toan TLKD se eho ket qua khae biet so vdi thue nghiem.
V. K £ ' T LUAN
Tren eo sd cae thdng sd vat ly eiia than TBD cd the
tinh toan TLKD eiia cpt than TBD theo eac cdng thUe nira thuc nghiem da dan. Tuy nhien, ket qua xac dinh TLKD theo ly thuyet sai lech kha nhieu so vdi sd lieu do dac thuc nghiem ma nguyen nhan chinh la do yeu td hinh dang hat chua dupe phan anh hoae phan anh chua dung trong cae cdng thUe nira thuc nghiem da din. Anh hudng ciia yeu td hinh dang eiia than TBD tdi TLKD c i n phai duoe nghien ciru de cd the dua ra dupe he sd hieu chinh phu hop vdi than TBD eho eac edng thUc da neu. Hien tai, ddi vdi than TBD, nen sir dung cdng thUe thue nghiem da xay dung de linh toan TLKD.
(Xem tiep trang 21)
5/2009 SA^
BAO HO LAO DONG 17Bang 7: Nguy ca doi vdi cac benh mit do khong dam bao A T- VSLD
~~~~~~-—-_______^^ Nhom Nguy CO ~ - _ _ Cach pha
thuoc Hudng gic khi phun Tam rira sau phun Sir dung hoa chat
Khong an toan /\ntoan Khong chu y Cd chii y Khong tam CO tam Nhieu I't
Nhdm benh (n = 120) 83(69,17%) 37 (30,83%) 68 (56,67%) 52 (43,33%) 27 (22,50%) 93 (77,50%) 8 (6,67%) 112(93,33%)
Nhom chirng (n = 300) 116(38,67%) 184(61,33%) 134(44,67%) 166(55,33%) 87 (29,00%) 213(71,00%) 19(6,33%) 281 (93,67%)
P p<0,01 p < 0,05 p < 0,05 p > 0,05 Bang 8: Nguy cdkhac doi vdi cac benh mit
~~~ ~—-—_____^ Nhdm Nguy CO ~~——_____
Noi dieu tri Nhad Chieu gio khi phun (cu the) Sir dung hoa chat
6 nha
Tram xa Nha tam Khac Ngupe chieu Xuoi chieu Nhieu I't
Nhdm benh (n = 120) 31 (25,83%) 89(74,17%) 17(14,17%) 103(85,83%)
68 (56,67%) 52 (43,33%) 8 (6,67%) 112(93,33%)
Nhdm chung (n = 250) 47(18,80%) 203(81,20%)
33(13,20%) 217(86,80%) 148 (59,20%) 102(40,80%) 19(7,60%) 231 (92,40%)
P p < 0,05
p > 0 5 p < 0,05
p>05
nghiem (+) vdi HCBVTV, do vay cdng ddng ngudi dan canh tac rau mie nhieu benh vdi ty le cao hon, trong dd cd cac benh mui hpng va mit la hpp ly.
IV. KET LUAN VA KIEN NGHI
IV.1. Ket luan:
Cae yeu td nguy eo cao ddi vdi sue khde ngudi dan canh tae che tai khu ehuyen canh che Dai TU, Thai Nguyen ed the xep tU eao den thip nhu sau: Nguy eo do pha HCBVTV khdng an toan la rit eao (p < 0,01); nguy co do tim va each t i m sau khi phun HCBVTV lua chpn dich vu y te khdng dii dp tin eay (tu chua benh d nha), khdng ehii y den chieu gid hoac phun HCBVTV theo chieu gid xudi tuong ddi eao (p < 0,05 ).
IV.2. Khuyen nghj:
- Tang cudng giao due truyen thdng ve AT-VSLD trong tidp xiic vdi HCBVTV d cdng ddng.
- Phat hien sdm cac nguy co ed lien quan den HCBVTV de cd phuong an du phdng hUu hieu, kjp thdi gdp phin giam thieu cae benh ed lien quan den HCBVTV ndi rieng, eac benh thudng gap ndi ehung trong edng ddng.
2. Le Thi Ciic, Pham Quang Trung. Tn/ang Dinh Hien va CS {2000): 'Tac hai cua HCBVTV doi vai sire khoe cong dong tai Ninh Binti~, Tap chi Y hoc du phong , tap X. so 3 {46), phu ban 2000, tr 106.
3. Nguyen Thi Ha (2004): 'Nghien ciru ton du thuoc BVTV trong rau. thi/c trang ve sinli an toan va sue khoe nhan dan trong sir dung thuoc BVTV tai phuang Tiic Duyen - Thai Nguyen". Luan van thae si Y hoc, Truang Dai hoe Y duac Thai Nguyen, tr 12- 35.
4. Do Ham {2007): VSLD va BNN. NXB Lao dong & Xa hoi, Ha Noi.
5. Nguyen Tuan Khanh, Do Ham {2006):
"SUe khoe ciia nong dan trong liia co tiep xuc vai HCBVTV tai Thai Nguyen sau 1 nam can thiep bSng giao due AT-VSLD". Tap ehi BHLD so 4/
2006. tr 20.
6. Ameerali Abdeali (2006): 'Risk manage- ment and occupational safety and health prac- tices in Singapore", The 22" annual conference of the Asia Pacific Occupational Safely and Health Organization, Bangkok, Thailand pp 127 - 32.
7. Ham Adzlin Adnan (2006): "Chiorpyrifos exposure - A ease study on paddy growers in Sekinchan, Malaysia", The 22" annual conference of the Asia Pacific Occupational Safety and Health Organization, Bangkok. Thailand, pp 82 - 83.
8. Taruli Sibuea (2005): "Risk Assessment". The 2P' annual conference of the Asia Pacific Occupational Safety and Health Organization, Bali Indonesia, pp 195 • 206. •
(Tiep theo trang 17)
U\ lieu tham khao
1. Bill Vinh Dien, Vu DUc Vong va cs (2004): "Du luang HCBVTV trong dat va nudc". Tap chi Y hoc thuc hanh, tap XIV, so 4 (67), phu ban, tr 31.
NGHIEN CUtJ ...
Tai iieu tham l(hao
1. Nguyen Thang Lai (2007): Phan tich ve 6 nhiem hai dung moi hUu ca trong MTLD va kha nang sir dung than hoat tinh dexiriy 6 nhiSm, Chuyen de tien si so 1.
2. Nguyen ThSng Lai (2007): Nghien ciru dac tinh hap phu dong luc va TLKD ciia than hoat tinh so dua Tra Bac TBD tren gid thi nghiem qui mo ban cong nghiep, Chuyen de tien si so 2.
3. Bird, R. Byron (1996): Transport phenomena, V\/isconsin: John Wiley & Sons.
4. Geankoplis, Christie J. {2003): Transport process and unit opera- tions, 4"'ed., New Jersey: Prentice Hall.
5. KentS. KnaebetA "How To" Guides for adsorber design. Adsorp- tion Research, Inc.. Dublin, Ohio,
6. Pierre Guimard and others (2004): Pressure drop for flow through packed beds.Transpoit process laboratory. Carnegie Mellon University
7. Subramanian R. S.: Flow through packed beds and fluidized beds, lhttD://www.elarkson.edu/Subramanian/eh301/notes/
paekfluidbed.pdf}.
8. Urgun, Sabri (1952): Fluid flow through packed columns. Chemi- cal engineering process, voi. 48. No 2. pp 89 • 94
9 SerpinovaE. N {1969):HapphuhaivakhicdngnghieptaibanianthU 2cbsira chira va bo sung, Nha xuat ban "Dai hoc". Matxcava (tieng Nga). •
5/2009 BAO HO LAO
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