thực tập chuyên đề kỹ thuật môi trường

TRNG I HC KHOA HC

Thc tp chuyn

K thut Mi trng

Bin son

Trng H Khoa hc Hu - Khoa Mi trng Thc tp chuyn ! K" thut mi trng

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I. MC TIU, C IM V NI DUNG MN HC

Hc phn Thc tp chuyn K thut mi trng c xy dng nhm to iu kin cho sinh vin chuyn ngnh K thut mi trng thc hnh cc kin thc hc lin quan n k thut mi trng trong phng th nghim. Cc ni dung trong hc phn cn nhm h tr thit thc cho sinh vin trong nghin cu khoa hc, trc tip l trong thi gian lm kha lun tt nghip hc k tip theo, v phn no trong thc hnh ngh nghip sau ny.

y l hc phn thc hnh mang tnh tng hp v c kin thc l thuyt cng nh k nng th nghim. Kin thc lin quan c sinh vin tch ly cc nm trc, ch yu t cc hc phn: Ha hc mi trng, K thut x l nc thi 1 v 2, Cng ngh mi trng, Phn tch mi trng,....

Cc bi th nghim trong hc phn ny c thit k theo hng m, khng b g p cng nhc v ni dung, quy trnh th nghim v thi lng tng bi, i hi sinh vin phi lp k hoch b tr thi gian thch hp. Thi lng cc bi th nghim c th khc nhau nhiu, ty vo ni dung ca bi.

Ni dung cc bi th nghim s bao gm cc lnh vc: x l nc, x l nc thi, x l kh thi, x l cht thi rn, phn tch mi trng,... Trong thi gian u, ph hp vi iu kin c s vt cht sn c, cc bi th nghim s tp trung vo x l nc, nc thi v phn tch nc-nc thi. Cc bi th nghim gm:

Bi 1. Kho st nh hng ca liu keo t v pH ln qu trnh keo t

Bi 2. nh gi kh nng hp ph ca than hot tnh

Bi 3. nh gi kh nng phn hy sinh hc ca nc thi

Bi 4. Khi ng v thit lp cc thng s vn hnh ca h thng bn hot tnh

Bi 5. nh gi vn hnh ca h thng bn hot tnh

Bi 6. nh gi kh nng nitrat ha ca bn hot tnh

II. PHN B THI GIAN HC PHN

Gii thiu v hng dn chung................................................(1 bui x 5 tit = 5 tit)

Bi 1................................ ....................................................... (1 bui x 5 tit = 5 tit)

Bi 2............... ....................................................................................(1 bui = 5 tit)

Bi 3. ..........................................................(1 bui x 5 tit + 5 bui x 2 tit = 15 tit)

Bi 4........................................................................................(2 bui x 5 tit = 10 tit)

Bi 5. .....................................................................................(2 bui x 5 tit = 10 tit)

Bi 6. .....................................................................................(2 bui x 5 tit = 10 tit)

------------------------------

Tng cng: 60 tit


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III.T CHC TH NGHIM

Ty theo s lung sinh vin, s chia thnh cc nhm, mi nhm khng qu 5 ngi. Mi nhm lm mt bi th nghim, sau quay vng n ht cc bi. Lch thi gian c th ca tng bi s c nhm sinh vin t lp, vi s ng ca gio vin hng dn.

S liu thc nghim thu c l chung cho c nhm, tuy nhin mi sinh vin lp bo co th nghim ring, trong trnh by kin thc, cc nh gi nhn xt theo hiu bit v quan im ca mnh.

IV. YU CU I VI SINH VIN

- c tht k cc bi th nghim, tho lun nhm v k hoch, phn cng cng vic trc khi vo lm.

- Hon thnh v np bo co th nghim trong vng 1 tun sau khi kt thc bi th nghim (theo mu bo co trang cui cng).

- Tun th cc ni quy ca Phng th nghim.


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(Thi lng: 5 tit thc hnh)

I. MC CH Qu trnh keo t c ng dng rng ri trong x l nc v nc thi, c bit lm trong nc. Bi thc hnh ny gip sinh vin lm quen vi th nghim xc nh cc thng s cho qu trnh keo t (JAR TEST). Trong bi, ch gii hn xc nh liu keo t v pH thch hp cho qu trnh keo t.

II. C S L THUYT

Xem l thuyt keo t hc phn Ha l-Ha keo, Ha mi trng, KT x l nc thi 2 v cc ti liu tham kho khc.

III. HA CHT-VT LIU

1. Dung dch cht keo t Dung dch Al2(SO4)3 7,5 g/L: Ha tan 14,6 g Al2(SO4)3.18H2O v nh mc n 1 L bng nc ct.

2. Mu nc c: Huyn ph t st trong nc

3. Dung dch NaOH 1N: Ha tan 20 g NaOH v thm nc ct n 500 mL.

4. Dung dch H2SO4 5N: Thm t t 70 mL H2SO4 . vo 400 mL nc ct; ngui, nh mc n 0,5 L.

IV. DNG C-THIT B 1. B JAR TEST vi 5 cc thy tinh 1 L.

2. My o pH (hay giy ch th pH)

3. My o c

4. Pipet

5. ng ong

V. TIN HNH

1. Kho st nh hng ca liu keo t ln qu trnh keo t - Khuy u mu, o pH v c ban u. Dng ng ong ly mu vo 5 cc, mi cc 0.75 L

mu.

- Dng pipet, cho dung dch cht keo t vo cc cc cha mu theo bng sau:

Cc s 1 2 3 4 5

mL dung dch Al2(SO4)3 7,5 g/L 1,0 1,5 2,0 2,5 3,0

Liu keo t, mg/L 10 15 20 25 30

- Khuy nhanh (60-80 rpm) trong 1 pht

- Gim tc khuy xung cn 20-30 rpm v duy tr trong 15 pht

- Dng khuy, theo di qu trnh lng bng cn trong cc cc, ghi ch thi gian lng hon ton ca tng cc.

- Sau 20 pht, gn ly phn nc lng v o c. Ghi kt qu o c nc lng t cc cc.

2. Kho st nh hng ca pH ln qu trnh keo t - Khuy trn u mu, o pH v c ban u. Dng ng ong ly mu vo 5 cc, mi cc

0,75 L mu.

- Dng cc dung dch H2SO4 5N v NaOH 1N iu chnh pH ca tng cc: cc 1 pH 5, cc 2 pH 6, cc 3 pH 7, cc 4 pH 8, cc 5 pH 9.


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- Dng pipet, cho dung dch cht keo t vo cc cc vi liu keo t cho hiu qu tt nht phn trn.

- Tin hnh khuy nhanh (60-80 rpm) trong 1 pht v khuy chm (20-30 rpm) trong 15 pht.

- Ngng khuy, theo di qu trnh lng bng cn trong cc cc, ghi ch thi gian lng hon ton ca tng cc.

- Sau 20 pht, gn ly phn nc lng v o c. Ghi kt qu o c nc lng t cc cc.

3. Tnh ton - Biu din trn th s thay i ca c theo liu keo t (bao gm c ca mu ban u, ng vi liu keo t = 0 mg/L)

- Biu din th thay i c theo pH (bao gm c ca mu ban u, ng vi pH ca mu).

VI. BO CO TH NGHIM Lp bo co th nghim theo mu, trong :

- Phn Tm tt l thuyt - nu khi nim keo t, bn cht qu trnh keo t, cc cht keo t thng dng, cc yu t nh hng n qu trnh keo t.

- Phn Kt qu th nghim - tng trnh cc s liu thu c dng bng v th nh nu phn tnh ton.

- Phn Nhn xt, nu cc nhn xt kt qu ca 2 phn th nghim, c nu r liu keo t tt nht v pH thch hp nht.


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I. MC CH Than hot tnh l mt trong cc cht hp ph s dng trong x l nc, nc thi loi mu, cc cht c lng nh Bi th nghim ny gip sinh vin thc hnh nh gi hot tnh hp ph ca than hot tnh qua kh nng hp ph mu dung dch xanh metylen. T kt qu th nghim, tnh ton cc thng s qu trnh hp ph.

II. C S L THUYT

Xem l thuyt hp ph cc hc phn Ha mi trng, KT x l nc thi 2 v cc ti liu tham kho khc.

III. HA CHT-VT LIU

1. Than hot tnh 2. Dung dch xanh metylen 150 mg/L: cn chnh xc 0,150 g metylen xanh ha tan trong nc ct v nh mc n 1 L.

IV. DNG C-THIT B 1. Bnh tam gic 250 mL

2. ng nghim 20 mL

3. Phu lc, giy lc

4. Cn in t

5. Spectrophotometer (o bc sng 724 nm)

V. TIN HNH

1. Xy dng ng chun xanh metylen - Pha dy cc dung dch chun xanh metylen c nng 0 - 150 mg/L t dung dch 150 mg/L vo

cc ng nghim theo bng sau:

ng nghim s 0 1 2 3 4 5

Nng dd. chun (mg/L) 0 30 60 90 120 150

Th tch dd. xanh metylen 150 mg/L, mL 0 2 4 6 8 10

Th tch nc ct, mL 10 8 6 4 2 0

- o hp th quang ca 5 dung dch chun bc sng 724 nm. Xy dng phng trnh ng chun (ph thuc hp th quang theo nng ).

2. Xc nh kh nng hp ph cc liu hp ph khc nhau - Ly vo 5 bnh tam gic mi bnh 50 mL dung dch xanh metylen 150 mg/L. Thm cc lng

cn than hot tnh khc nhau vo cc bnh theo bng sau:

Bnh s 1 2 3 4 5

Lng than hot tnh, g 0,05 0,10 0,20 0,30 0,40

Liu hp ph tng ng, mg/L 1000 2000 4000 6000 8000

- y nt bnh, lc u cc bnh.

- Sau , c mi 15 pht li lc u cc bnh, trong thi gian 120 pht.

- Lc cc mu qua giy lc, thu dch lc v o hp th quang bc sng 724 nm.


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- Tnh nng xanh metylen cn li (nng cn bng) trong cc bnh theo ng chun xy dng trn.

3. Tnh ton T s liu th nghim c c, tnh:

a. Hiu sut x l mu (loi mu) tng bnh th nghim:

100(%) E0

0

=C

CC e (1)

b. Hot tnh hp ph ca than tng bnh th nghim:

C

e

m

CC )(05,0(mg/mg) AC 0

= (2)

Trong :

- C0: nng xanh metylen ban u = 150 mg/L

- Ce: nng xanh metylen sau hp ph, mg/L

- mC: Khi lng than cho vo, mg

c. Cc h s trong phng trnh hp ph Freundlich. Cch tnh nh sau:

+ Tuyn tnh ha phng trnh Freundlich c

feC

KCnm

xlnln

1ln +=

Trong :

- x: Lng cht b hp ph, mg

- mC : Lng cht hp ph, mg

x/mC = AC: hot tnh hp ph

- n, Kf: cc h s thc nghim

+ T dy s liu th nghim, xy dng ng tuyn tnh: ln(x/mC) = a lnCe + b

+ Tnh cc hng s n v Kf t h s gc a v on ct trc tung b.

VI. BO CO TH NGHIM Lp bo co th nghim theo mu, trong :

- Phn Tm tt c s l thuyt - nu khi nim hp ph, vn tt v bn cht qu trnh hp ph (vt l, ha hc), cc cht hp ph thng dng, phng trnh ng nhit hp ph,...

- Phn Kt qu th nghim - tng trnh cc s liu thu c cc mc nu trong phn tin hnh. V th bin thin E v AC theo liu hp ph.

- Phn Nhn xt, nu cc nhn xt kt qu th nghim.


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I. MC CH nh gi kh nng phn hy sinh hc (PHSH) ca ca mu nc thi th thng qua xc nh thc nghim hng s tc phn ng BOD v gi tr BOD ton phn .

II. C S L THUYT Qu trnh PHSH cc hp cht hu c trong nc thi xy ra theo ng hc bc 1:

tt Lk

dt

dL= (1)

Trong : k - hng s tc phn ng BOD, ngy-1; Lt - nhu cu oxy ca cc cht hu c cn li thi im t, mg/L. Bin i ton hc (1) s cho biu thc tnh BOD ca mu sau thi gian t (ngy):

BODt = Lo - Lt = Lo - Loe-kt = Lo (1 - e

-kt ) (2) Trong Lo l gi tr BOD ton phn, l lng oxy tiu th ln nht khi cc cht hu c trong nc thi b PHSH hon ton. Hng s k phn nh tc PHSH cht hu c trong nc thi xy ra nhanh hay chm. Gi tr L0 (hay BODu) th hin tng nng cc cht hu c d b PHSH c trong nc thi. Gi tr k v Lo c xc nh t dy s liu thc nghim BOD sau cc thi gian t khc nhau. C nhiu phng php c s dng tnh k v Lo. Cc phng php ny ch khc nhau v th thut ton hc khi gii k v L0 t phng trnh (2). Phng php Thomas Phng php ny da trn s ging nhau v khai trin dy ca 2 hm s: F1 = 1 - e

-kt v F2 = (kt) (1 + (1/6)kt )-3.

[ ] 3)t(k24

12)t(k6

1)t(k0,51t)(k1F +=

[ ] 3)t(k21,9

12)t(k6

1)t(k0,51t)(k2F +=

Hai s hng u ging nhau, s hng th ba ch khc mt t. Nh vy, phng trnh tc phn ng BOD (phng trnh 2) c th vit li gn ng nh sau:

BODt = Lo(kt)[1 + (1/6)kt ]-3 (5)

Bin i (5) v ly cn bc ba hai v: )t(1/3)o(L6

2/3k1/3)oLk(

11/3

tBOD

t+=

th (t/BODt)1/3 theo t l ng thng c on ct trc tung l: A = (kLo)

-1/3 v dc

1/3)oL(6

2/3kB = . T y tnh c k: k = 6B/A v tnh c Lo: L0 = 1/(6A

2B)

Nh vy cc bc xc nh k, Lo theo phng php Thomas nh sau: (1). T cc kt qa thc nghim ca BODt, tnh (t/BODt)

1/3. (2). Biu din hm tuyn tnh (t/BODt)

1/3 theo t. (3). Tnh on ct trc tung A v dc B. (4). Tnh k, Lo t A v B.

III. HA CHT-VT LIU

1. Cc ha cht dng xc nh BOD - Dung dch m pht-pht: ha tan 8,5 g KH2PO4; 21,75 g Na2HPO4.7H2O v 1,7g NH4Cl

trong 500 mL nc ct ri pha long n 1 lt.


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- Dung dch MgSO4: ha tan 22,5 g MgSO4.7H2O trong nc ct v pha long n 1 lt. - Dung dch CaCl2: ha tan 27,5 g CaCl2 trong nc ct v pha long n 1 lt. - Dung dch FeCl3: ha tan 0,25 g FeCl3.6H2O trong nc ct v pha long n 1 lt.

2. Cc ha cht xc nh COD (xem Phng php xc nh COD ph lc 3-A km theo)

3. Mu: Nc thi th (nc cng)

IV. DNG C-THIT B 1. Chai BOD (chai Winkler) 300 mL. 2. Pipet 3. Cc hay dng c cha th tch > 2 L 4. My o DO

5. My khuy t 6. My sc kh 7. T lnh (20 0,5oC) 8. Dng c xc nh COD

V. TIN HNH

1. Chun b nc pha long - c 1 L nc pha long, thm 1 mL mi dung dch mui v m III.1 vo nc ct, thm 1

mL bn hot tnh (khuy u x nui khi ht) ri pha long n 1 lt. Khuy trn u v sc khng kh trong 20-30 pht.

2. Chun b mu - Mu nc thi c ly t ngun thi ngay trc khi th nghim hay c gi trong t lnh

khng qu 24 gi. Khuy trn u trc khi ly phn mu cho th nghim.

- Tnh ton mc pha long thch hp (trong khong 20-50 ln).

- Tin hnh pha long mu c th tch cui cng l 2 L. Khuy trn u trong 5 pht v o DO ca mu pha long ban u.

- Cho mu pha long vo 5 chai Winkler. Dng ng nha np mu vo chai, cho u ng st gn y chai trnh xo trn. Ly mu n d trn phn ming chai, dng nt y nhanh v trnh to bt kh bn trong chai.

- t 5 chai vo t BOD 20oC.

3. Xc inh COD Tin hnh xc nh COD ca mu nc thi ban u, dng phng php o hp th quang 420 nm (xem quy trnh phn tch COD km theo). Pha long mu 2 mc: 2 v 4 ln v phn hy cng mu trng. S dng ng chun c sn tnh COD. Nu mt trong 2 mc pha long ngoi ng chun th chn gi tr cn li. Nu c 2 cng trong ng chun th ly gi tr trung bnh.

4. o DO sau cc thi gian khc nhau - Tin hnh o DO sau 1 ngy, 2 ngy, 3 ngy, 4 ngy, 5 ngy; mi ln o trn mi chai. Khi o DO, t chai Winkler trn my khuy t, th que khuy vo, khuy nh trong sut thi gian o vi in cc ca my o DO.

5. Tnh ton - Tnh BODt vi t = 1, 2, 3, 4, 5 ngy.

- Tnh gi tr k v Lo ca mu nc thi theo phng php Thomas, theo cc bc t (1) n (4) nh phn I. S dng bng tnh MS Excel.

- Tnh cc t l BOD5/COD, BODu/COD.

VI. BO CO KT QU TH NGHIM Lp bo co th nghim theo mu, trong :

- Phn Tm tt l thuyt trnh by nguyn tc phng php tnh k v L0.

- Phn Kt qu th nghim - tng trnh cc s liu thu c nh nu phn V.3., V.4 v V.5.

- Phn Nhn xt, nu cc nhn xt kt qu thu c.


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Ph lc 3-A: XC NH COD PHNG PHP HI LU KN-TRC QUANG (Theo: U.S. Standard methods, 1999)

I. NGUYN TC - Khi phn hy mu, ion dicromat (Cr2O7

2-) oxy ha cht hu c v b kh v cromic (Cr+3). C hai dng Cr ny u hp th nh sng trong vng kh kin. vng 400 nm, ion dicromat (mu vng) hp th mnh, ion cromic (mu xanh) hp th rt yu. Ion cromic hp th mnh vng 600 nm trong khi ion dicromat khng hp th. - Vi mu c COD cao (100-900 mg/L) o hp th quang dung dch sau phn hy 600 nm (o Cr3+ gia tng). Vi mu c COD 90 mg/L o hp th quang dung dch sau phn hy 420 nm (o Cr2O7

2- gim). II. THIT BI DNG C - ng nghim phn hy mu: Dng ng thy tinh borosilicat, c np nha vn cht v lp m TFE, 20 mL. - B un nhiu ch kim sot c nhit (150 2oC). - Spectrophotometer o c 420 nm hay 600 nm. III. HA CHT 1. Dung dch phn hy cho khong COD cao: Ha tan 10,216 g K2Cr2O7 ( tinh khit cao) c sy kh 150oC trong 2 gi trong 500 mL nc ct. Thm 167 mL H2SO4 . v 33.3 g HgSO4. Khuy tan, lm ngui n nhit phng v pha long n 1 L. 2. Dung dch phn hy - cho khong COD thp: Tng t nh trn, nhng ch s dng 1,022 g K2Cr2O7. 3. Dung dch H2SO4/Ag

+: Thm 5,5 g Ag2SO4 vo 1 kg H2SO4, qua m cho tan ht. 4. Dung dch chun kali hydrophtalat (KHP) (COD 500 mg/L): Nghin nh v sy kh KHP n khi lung khng i 110oC. Ha tan 425 mg trong nc ct v pha long n 1 L. Dung dch ny bn khi gi trong t lnh, nhng tt nht l khng s dng khi pht hin du hiu sinh trng ca VSV bng mt thng. IV. QUY TRNH PHN TCH 1. Chun b cc dung dch lm vic: ty khong COD trong mu

Khong COD thp (100 mg/L) S1 S2 S3 S4 S5

(0 mg/L) : nc ct (15 mg/L) : 1,5 mL dd. chun + nc ct n 50 mL (30 mg/L) : 3,0 mL dd. chun + nc ct n 50 mL (60 mg/L) : 6,0 mL dd. chun + nc ct n 50 mL (90 mg/L) : 9,0 mL dd. chun + nc ct n 50 mL

(0 mg/L) : nc ct (50 mg/L) : 1 mL dd. chun + 9 mL nc ct (100 mg/L): 2 mL dd. chun + 8 mL nc ct (250 mg/L): 5 mL dd. chun + 5 mL nc (500 mg/L): dd. chun

2. Chun b mu: Nu COD cao (>500 mg/L), pha long mu c nng COD trong khong ng chun. 3. Cc bc phn tch 4. Tnh ton: a. Khi o 600 nm - ng chun bnh thng, tc ph thuc hp th quang ca cc dung dch chun theo nng COD. Tnh COD ca mu theo ng chun t hp th quang ca mu. b. Khi o 420 nm ng chun biu din ph thuc hiu s hp th quang ca mu trng vi mu chun theo nng COD. Tnh COD ca mu theo ng chun t hiu s hp th quang ca mu trng v mu cn xc nh. Ch : Nitrit ng gp gi tr COD 1,1 mg O2/mg NO2-N, nn vi mu c NO2-N bit, tr phn COD ng gp do nitrit. Cng c th dng acid sulfamic lai nh hng ca nitrit vi t l 10 mg sulfamic/1 mg NO2-N.

(*)Th tch mu, dung dch phn hy v H2SO4 thay i ty thuc vo kch thc ng nghim..

2,5 mL dung dch chun/mu(*) (trong ng nghim 20 mL)

Thm 1,5 mL dung dch phn hy

Cho vo b un ( gia nhit trc n 150oC) v un trong 2 gi

o hp th quang 420 nm hay 600 nm(**)

Lm ngui t t n nhit phng

Thm cn thn 3,5 mL H2SO4/Ag+ (cho chy dc thnh ng

nghim). Vn cht np, o vi ln trn

(**)Khi o 600 nm dng mu trng thit lp gi tr zero. Khi o 420 nm dng nc ct thit lp gi tr zero.


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I. MC CH Bn hot tnh l h thng x l sinh hc c bn v ph bin, s dng trong x l nc thi lai cc cht hu c. Bi thc hnh ny gip sinh vin hiu c nguyn tc vn hnh ca h thng bn hot tnh, thc hnh thao tc khi ng v thit lp mt s thng s vn hnh ca h thng.

II. C S L THUYT

Xem l thuyt qu trnh bn hot tnh hc phn KT X l nc thi 1 v cc ti liu tham kho khc.

III. HA CHT-VT LIU 1. Bn hot tnh: c nui lu di phng th nghim vi mi trng gm nc chit tht b, pepton, cc mui khong v c lm thch nghi vi mi trng nc thi tng hp ca bi th nghim.

2. Nc thi tng hp, c thnh phn nh sau:

Thnh phn Nng , mg/L (1). Glucose 150 (2). CH3COONH4 100 (3). NaHCO3 500 (4). KH2PO4 18 (5). NaCl 1,0 (6). KCl 1,4 (7). CaCl2.2H2O 1,9 (8). MgSO4.7H2O 2,0

Cc thnh phn trn c pha di dng dung dch gc v NT tng hp c chun b bng cch pha long vi nc my mi khi s dng (pha 10 hay 20 L).

Dung dch gc Nng , g/L mL dng pha 10 L NT tng hp 1. Glucose 30 50 2. Amoni acetate 20 50 3. NaHCO3 50 100 4. KH2PO4 7,2 25 5. Dung dch hn hp mui: 10 - NaCl 1,0 - KCl 1,4 - CaCl2.2H2O 1,9 - MgSO4.7H2O 2,0

IV. DNG C- THIT B 1. H thng bn hot tnh quy m PTN (xem

hnh v)

2. ng ong

3. Dng c xc nh SS

4. My o pH

5. Nhit k


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V. TIN HNH

1. Lp rp v iu chnh cc thit b o - o th tch ca b phn ng: dng ng ong 1 L cho nc my vo b cho n khi va trn ng

dn ra. c th tch V ca b (lm trn n 0,1 L). Tho cn nc trong b.

- o v iu chnh lu lng cc bm nc thi vo v lu lng bn hi lu: tnh ton cc lu lng Q v QR sao cho t iu kin HRT = 10 h v t l bn hi lu QR/Q = 1. Cch iu chnh bm lu lng xem Ph lc 4-A.

- Kt ni cc u ni ca h thng.

- Kim tra ng h o lu lng kh v iu chnh v mc 1,0 1,5 L/min.

2. Khi ng h thng - Pha 10 L nc thi tng hp.

- Ly 5 L bn hot tnh t x bn vo x nh, ng thi ly 50 mL vo ng ong.

- Phn trong ng ong dng xc nh nng SS v VSS theo ph lc 4-B.

- Phn trong x nh, lng trong 30-45 pht, gn b phn nc lng. Cho phn bn lng c vo b phn ng. Dng nc thi tng hp (th tch bng V) trng x v cho vo b. Thm nc my n ngang mc trn ca ng dn ra (tc b s c np bng NT tng hp pha long 2 ln).

3. Vn hnh h thng - Trong 4-6 gi u tin, tt bm NT vo, ch m bm bn hi lu v sc kh h vn hnh vi

ch m. Sau , bt u m bm NT vo.

- Ch : pha b sung 5 L NT tng hp

4. Tnh ton - T thnh phn ca NT tng hp, tnh nhu cu oxy l thuyt (ThOD) v nng NH4-N u

vo.

- Tnh nng SS, VSS trong b phn ng.

VI. BO CO KT QU Kt hp bi th nghim ny v bi s 5 vit mt bo co chung. Bo co th nghim theo mu, cc ni dung hng dn xem cui bi 5.

Bm kh o lu lng kh

B cha NT vo

Bm lu lng NT vo

Bm lu lng bn hi lu

B phn ng V 5 L

B lng

NT ra


12

Ph lc 4-A: IU CHNH BM LU LNG Cc bm lu lng l bm nhu ng, lu lng ty thuc vo tc quay ca cc trc r-lng u quay v kch c ca ng cao su gn vo cc trc u quay. Tc quay c iu chnh bng cc ch s trn bm.

Di y l th lu lng-ch s tc ca 2 bm s dng trong th nghim.

Tuy nhin, chnh xc, sau khi chon ch s tc cn kim tra li lu lng thc t bng cch ong th tch bm c sau mt khong thi gian xc inh (v d 6 pht).

Cc bc tin hnh:

1. T lu lng cn t c v kch c ng, tra ch s tc tng ng trn th.

2. iu chnh bm v ch s tc tra cu c.

3. M bm, ch n khi khng cn bt kh trong ng dn.

4. Dng ng ong 100 mL hng nc u ra ca bm trong 6 pht (canh thi gian chnh xc bng ng h).

5. Tnh lu lung gi thc t (10 ln th tch thu c).

6. Tng hay gim cht t ch s tc mt cch thch hp v lp li cc bc 4-5-6 n khi c ng lu lng cn t.

Bm SMP-21 Bm RP-2000


13

Ph lc 4-B: XC NH CHT RN L LNG (SS) V CHT RN L LNG D BAY HI (VSS) PHNG PHP TRNG LUNG

(Theo: U.S. Standard methods, 1999) I. NGUYN TC - Lc mu (ng nht) qua giy lc tiu chun cn trc v sy kh phn nm li trn giy lc 103-105oC. Phn gia tng khi lung so vi giy lc l cht rn l lng (SS hay TSS). - Nung phn cht rn l lng 550oC n khi lng khng i. Phn khi lng mt i l cht rn l lng d bay hi (VSS). II. THIT BI DNG C 1. Giy lc tiu chun (glass fiber; 0,45 m). 2. B lc chn khng (gi lc, bnh ht, bm chn

khng). 3. Da cn bng nhm

4. T sy (103-105oC) 5. L nung (550oC). 6. Bnh ht m (desiccator) 7. Cn phn tch (c n 0,1 mg)

III. QUY TRNH PHN TCH 1. Chun b mu: Mu phi c khuy trn ng nht ngay trc khi lc. 2. Cc bc phn tch 3. Tnh ton:

a. SS 1000mu tch th

mmmg/LSS, 01

= b. VSS 1000

mu tch th

mmmg/LVSS, 21

=

Ch : c kt qu i din, cn phn tch lp li 2 ln v ly gi tr trung bnh.

Bm chn khng

Bnh ht

Gi lc Giy lc

a cn bng nhm v giy lc

(*)Th tch mu cn ly sao cholng cht rn gi li trong khong 2,5-200 mg.

Chun b giy lc Sy giy lc v a nhm 103-105oC trong 1 gi Lm ngui trong bnh ht m n nhit phng Cn khi lng a + giy lc (m0, mg)

Sy-lm ngui-cn Sy a nhm+giy lc trong t sy 103-105oC trong 1 gi Lm ngui trong bnh ht m n nhit phng Cn khi lng a+giy lc+cht rn. Lp li sy-lm ngui-cn (sy 30 pht) cho n khi thay i khi lng khng qu 4% so vi lng cn ln trc (m1, mg).

Lc mu Lp giy lc, lm t bng mt t nc ct, m bm chn khng Rt th tch mu tnh trc vo phu(*). Khi lc ht mu, ra thnh phu 3 ln vi 10 mL nc ct mi ln. Ly giy lc c cht rn cho vo a nhm.

Nung-lm ngui-cn Cho a nhm+giy lc+SS vo l nung t sn 550oC, nung trong 15-20 pht Lm ngui mt phn ngoi khng kh, ri trong bnh ht m. Cn khi lng a+giy lc+cht rn. Lp li nung-lm ngui-cn (nung 10 pht) cho n khi thay i khi lng khng qu 4% so vi lng cn ln trc (m2, mg).

SS

VSS


14


I. MC CH Bi thc hnh ny l phn tip theo ca bi s 4, gip sinh vin hiu c nguyn tc vn hnh ca h thng bn hot tnh v nh gi hiu qu x l ca h thng.

II. C S L THUYT

Xem l thuyt qu trnh bn hot tnh hc phn KT X l nc thi 1 v cc ti liu tham kho khc.

III. HA CHT-VT LIU

1. Cc ha cht dng xc nh COD 2. Nc thi tng hp, xem bi TN s 4.

IV. DNG C- THIT B 1. H thng bn hot tnh t bi 4 2. ng ng mu 3. Dng c xc nh COD 4. Dng c xc nh SS

5. My o pH 6. My o DO 7. Nhit k

V. TIN HNH Th nghim bi ny c tin hnh 3 ngy sau th nghim khi ng h thng bi 4, v c thc hin trong 2 ngy.

1. o cc thng s vn hnh Trong 2 ngy th nghim, tin hnh o cc thng s sau y trong b phn ng (mi ngy o 1 ln): nhit , pH, DO.

2. Ly mu v phn tch mu - Trong 2 ngy th nghim, ly mu nc thi u vo ( dng c cha) v mu nc thi sau x l ( cui ng dn ra), mi ngy 1 ln. Mi mu 50 mL, cho vo ng nha ng mu. ngy th nht, bo qun 2 mu trong t lnh. ngy th hai, tin hnh phn tch COD, NH4-N cho c 4 mu. Xem phng php phn tch COD Ph lc 3-A, bi th nghim s 3.

- Trong ngy th hai, ly 50 mL mu MLSS trong b phn ng xc nh nng SS v VSS. Xem phng php xc nh SS, VSS Ph lc 4-B, bi th nghim s 4.

3. Tnh ton - Tnh COD u vo, u ra ca 2 ngy th nghim v hiu sut x l COD.

- Tnh ti trng hu c ca h thng (kg-COD/m3/d)

- Tnh NH4-N u vo, u ra ca 2 ngy th nghim v hiu sut x l NH4+. Xem phng php xc

nh NH4-N Ph lc 5-A.

- Tnh nng SS, VSS trong b phn ng. So snh vi SS, VSS ban u xc nh bi s 4.

- Tnh cc gi tr F/M, tc tiu th c cht ring i vi x l COD.

VI. BO CO KT QU Lp bo co th nghim cho c 2 bi 4 v 5 theo mu, trong :

- Phn Tm tt c s l thuyt - nu s , nguyn tc hot ng ca h thng bn hot tnh; nu cc phng trnh tnh ton cn thit lin quan.

- Phn Kt qu th nghim - tng trnh cc s liu thu c v tnh ton c cc mc nu trong phn tin hnh ca c 2 bi.

- Phn Nhn xt, nu cc nhn xt kt qu th nghim; nh gi, so snh vi s liu l thuyt.


15

Ph lc 5-A XC NH NIT AMNI PHNG PHP PHENATE

(Theo: Standard methods, 1999) I. NGUYN TC - Trong mi trng kim, amniac phn ng vi hypoclorite v phenol, xc tc bi sodium nitroprusside to hp cht indophenol mu xanh sm. o hp th quang 640 nnm. - Yu t cn tr: Ca, Mg (loi bng cch to phc vi citrat), H2S (loi bng cch acid ha mu vi HCl n pH =3). - Khong xc nh n 0,6 mg NH4-N/L. II. THIT BI DNG C - ng nghim 25 mL - My khuy ng nghim

- Ni cch thy hay t sy (n nhit 40 oC) - Spectrophotometer (o c 640 nm).

III. HA CHT 1. Dung dch phenol (R1): Ha tan 11.1 mL phenol lng (>89%) trong C2H5OH (95% v/v), nh mc n 100 mL. Do phenol ng rn nhit thng, phi un cch thy lm tan chy phenol. Ch : thao tc cn thn, eo gng tay v knh bo v mt, tin hnh ni thong gi! Tt nht nn chun b hng tun. 2. Dung dch sodium nitroprusside 0.5 % w/v (R2): Ha tan 0.5 g Sodium nitropursside trong 100 mL nc ct (hay nc trao i ion) (Bo qun 1 thng trong chai mu nu, trong t lnh). 3. Dung dch citrate/kim (R3): Ha tan 50 g trisodium citrate v 2.5 g NaOH trong nc ct (hay nc trao i ion), nh mc n 250 mL. 4. Dung dch sodium hypochlorite NaClO 5 % (R4): Ha tan 2 mL dung dch NaClO thng phm n 50 mL vi nc trao i ion hay nc ct (Bo qun 1 tun trong t lnh). 5. Dung dch oxi ha (R5): Trn ln 20 mL dd R3 vi 5 mL R4 (chun b ngay trc khi phn tch). 6. Dung dch gc NH4-N (150 mg-N/L): ha tan 0.573 g NH4Cl ( sy kh 100

oC trong 1 gi) trong nc trao i ion hay nc ct, nh mc n 1 L. IV. QUY TRNH PHN TCH 1. Chun b cc dung dch trung gian v dung dch lm vic a. Dung dch trung gian (1.5 mg-N/L): 1 mL dung dch gc (150 mg/L) pha long v nh mc n 100 mL. b. Cc dung dch chun (dung dch lm vic) (0, 0.15, 0.30, 0.45, 0.60 mg-N/L)

S1 (0 mg/L) : 10 mL nc ct S2 (0.15 mg/L) : 1 mL dd. trung gian + 9 mL nc ct S3 (0.30 mg/L) : 2 mL dd. trung gian + 8 mL nc ct S4 (0.45 mg/L) : 3 mL dd. trung gian + 7 mL nc ct S5 (0.60 mg/L) : 4 mL dd. trung gian + 6 mL nc ct

2. Chun b mu + Nu mu c cha cht rn l lng, phi lc qua giy lc 0.45 m. + Pha long mu c nng NH4-N trong khong 0 ~ 0.6 mg/L (th tch cui cng: 10 mL) 3. Cc bc phn tch 4. Tnh ton: Lp ng chun, tnh nng NH4-N trong cc mu theo ng chun

10 mL dung dch chun/mu (trong ng nghim 25 mL)

Thm 0,5 mL R1, trn u



Gi nhit 40 oC trong ni cch thy 15 pht

o hp th quang 640 nm


16


I. MC CH Trong bn hot tnh c cha cc vi khun c kh nng thc hin qu trnh nitrat ha, tc oxi ha amoni thnh nitrit v nitrat. Bi th nghim ny nhm xc nh kh nng nitrat ha ca bn hot tnh trong iu kin th nghim m.

II. C S L THUYT

Gi thit qu trnh oxi ha sinh hc amoni trong iu kin th nghim tun theo ng hc Monod v gi s nng bn thay i khng ng k trong khong thi gian th nghim. T nng c cht amoni (NH4-N) mt i hay nng tng NO2-N v NO3-N (gi chung l NOx-N) to thnh sau tng khong thi gian, tnh ton tc oxy ha ring cc i, s dng dng bin i tuyn tnh ca phng trnh Monod.

SK

kSXr

SN += (1)

11

kSk

K

r

X S

N

+= (2)

Trong : rN: tc nitrat ha, mg NH4-Ngim/L/h hay mg NOx-Nto thnh/L/h k: tc nitrat ha ring cc i, mg-N/g-VSS/h S: nng c cht amoni, mg-N/L X: nng sinh khi, mg-VSS/L KS: hng s

III. HA CHT

1. Mi trng th nghim* - (NH4)2SO4 : 471,7 mg/L (100 mg NH4-N/L) - KH2PO4 : 88 mg/L - NaHCO3 : 630 mg/L

- MgSO4.7H2O : 50 mg/L - CaCl2.2H2O : 5 mg/L - Dung dch Fe-EDTA** : 1 mL/L

iu chnh pH n 7,5 bng dung dch NaHCO3 10%.

Ghi ch: *Pha mi trng TN t cc dung dch gc. Sinh vin phi tnh ton th tch dung dch gc cn thit.

**Dung dch Fe-EDTA: Ha tan ring r 2 g FeSO4.7H2O v 2 g Na2EDTA trong 200 mL nc ct. Trn chung 2 dung dch ,thm 1 git H2SO4 5N, nh mc n 500 mL v khuy trn lin tc qua m.

2. Ha cht xc nh nit amoni, nit nitrit v nit nitrat (xem cc Ph lc tng ng).

IV. DNG C 1. Bnh Erlenmeyer dung tch 1,0 L 2. Bm khng kh 3. B iu nhit 30oC. 4. Dng c phn tch NH4-N, NOx-N.

V. TIN HNH

1. X l bn hot tnh - Dng ng ong, ly 200 mL bn hot tnh t x nui bn PTN.

- Cho vo cc, khuy u trn my khuy t v ht ra 50 mL xc nh SS and VSS (xem phng php xc nh Ph lc 4-B Bi th nghim s 4).

- Phn 150 mL bn cn li c x l nh sau:

Bnh Erlenmeyer 1000mL

Bm khng kh

B iu nhit


17

a. Lc ht qua phu lc thy tinh xp (khng giy lc),

b. Ngng bm ht, dng bnh tia nc ct ra phn bn nm trn phu (dng 15-20 mL nc)

c. Lp li thao tc lc-ra 2-3 ln na cho n khi th nc lc bng thuc th hin mu xc nh nitrit khng cn hin mu hng.

3. Tin hnh th nghim m - Dng mi trng th nghim ra phu lc nhiu ln v chuyn ton b vo bnh tam gic. Thm

ht 1 L mi trng th nghim vo.

- Cho u khuch tn kh vo bnh v t bnh vo b iu nhit 30oC.

- Sc khng kh trong 1 pht, lng, dng syringe ht 20 mL mu.

- Sc khng kh tr li. Kim tra oxy ha tan trong bnh, bo m DO ln hn 3 mg/L.

- Sau mi 1 gi ly 1 mu bng cch ngng sc kh, lng 1 -2 pht ri ht 20 mL mu bng syringe. Ly tt c 5 mu, tc sau 1, 2, 3, 4, v 5 gi.

- Tt c mu ly trong syringe c lc qua giy lc 0,45 m, cha vo chai ng mu v bo qun trong t lnh phn tch cng mt ln sau ny.

4. Phn tch mu Phn tch cc mu lc vi cc thng s: NH4-N (xem ph lc 5-A), NO2-N (xem ph lc 6-A), NO3-N (xem ph lc 6-B). Ch pha long mu ph hp khong phn tch. Tng nng NO2-N v NO3-N gi l NOx-N.

5. Tnh ton T bng s liu th nghim: t, gi 0 1 2 3 4 5

NH4-N, mg-N/L S0 S1 S2 S3 S4 S5

NOx-N, mg-N/L N0 N1 N2 N3 N4 N5

- Lp bng tnh: Khong thi gian, h - 1 2 3 4 5

NH4-N gim, mg/L - S0-S1 S0-S2 S0-S3 S0-S4 S0-S5

NOx-N to thnh, mg/L N0-N1 N0-N2 N0-N3 N0-N4 N0-N5

rN, mg NH4-N/L/h - (S0-S1)/1 (S0-S2)/2 (S0-S3)/3 (S0-S4)4 (S0-S5)/5

rN, mg NOx-N/L/h (N0-N1)/1 (N0-N2)2 (N0-N3)/3 (N0-N4)/4 (N0-N5)/5

X/rN, mg-VSS/mg-N/h -

X/rN, mg-VSS/mg-N/h -

1/S, (mg-N/L)-1 - 1/S1 1/S2 1/S3 1/S4 1/S5

- Tnh h s gc a v on ct trc tung b ca cc phng trnh tuyn tnh: X/rN = a1/S + b (theo tc gim NH4-N) v X/rN = a1/S + b (theo tc tng NOx-N). T phng trnh 2, tnh k, k.

VI. BO CO KT QU Lp bo co th nghim theo mu, trong :

- Phn Tm tt c s l thuyt - nu vn tt v qu trnh nitrat ha (2 giai on); nguyn tc tnh tc nitrat ha; nu cc phng trnh tnh ton cn thit lin quan phn V.4.

- Phn Kt qu th nghim - tng trnh cc s liu thu c v tnh ton c cc mc nu trong phn tin hnh, V cc th biu din thay i nng NH4-N v NOx-N theo thi gian phn ng.

- Phn Nhn xt, nu cc nhn xt kt qu th nghim; so snh 2 gi tr k, k, gii thch.


18

Ph lc 6-A:

XC NH NIT NITRIT PHNG PHP TRC QUANG (Theo: Standard methods, 1999)

I. NGUYN TC - Nitrit c xc nh qua s to thnh hp cht mu azo tm pH 2.0-2.5 bng phn ng ghp azo ca sulfanilamide c diazo ha vi N-(1-naphthyl)-ethylenediamine dihydrochloride (NED dihydrochloride). o hp th quang 543 nm. - Khong xc nh n 0,3 mg NO2-N/L. II. THIT BI DNG C - ng nghim 25 mL - My khuy ng nghim

- Pipet - Spectrophotometer (o c 543 nm).

III. HA CHT 1. Thuc th to mu Thm 25 mL H3PO4 . vo 200 mL nc trao i ion hay nc ct. Thm 2,5 g sulfanilamide, khuy cho tan. Thm tip 0,25 g NEDA [N-(1-Naphthyl)-ethylendiamine.2H2O], khuy cho tan. Thm nc ct n 250 mL (Bo qun c 1 thng trong t lnh). 2. Dung dch gc NO2-N (100 mg/L): Ha tan 0,4928 g NaNO2 ( c sy kh 100

oC trong 1 h) trong nc ct v nh mc n 1 L (Bo qun vi 1mL chloroform c 1 thng, trong chai sm mu v trong t lnh). IV. QUY TRNH PHN TCH 4. Chun b cc dung dch trung gian v dung dch lm vic a. Dung dch trung gian (1 mg/L): 1 mL dung dch gc (100 mg/L) pha long v nh mc n 100 mL. b. Cc dung dch chun (dung dch lm vic) (0, 0.05, 0.10, 0.20, 0.30 mg/L)

S1 (0 mg/L) : 20 mL nc ct S2 (0.05 mg/L) : 1 mL dd. trung gian + 19 mL nc ct S3 (0.10 mg/L) : 2 mL dd. trung gian + 18 mL nc ct S4 (0.20 mg/L) : 4 mL dd. trung gian + 16 mL nc ct S5 (0.30 mg/L) : 6 mL dd. trung gian + 14 mL nc ct

5. Chun b mu + Nu mu c cha cht rn l lng, phi lc qua giy lc 0.45 m. + Nu mu c pH khng nm trong khong 5 n 9, iu chnh pH bng cc dung dch 1N HCl hay NH4OH. + Pha long mu c nng NO2-N trong khong 0 ~ 0,3 mg/L (th tch cui cng: 20 mL) 6. Cc bc phn tch

4. Tnh ton: Lp ng chun, tnh nng NO2-N trong cc mu theo ng chun.

Ch : i vi cc trng hp nng NO2-N thp v cn chnh xc cao, dung dch gc NaNO2 phi c xc nh nng chinh xc vi dung dch chun KMnO4.

20 mL dung dch chun/mu (trong ng nghim 25 mL)

Thm 1 mL thuc th to mu, trn u

Ch 15-20 pht

o hp th quang 543 nm


19

Ph lc 6-B: XC NH NIT NITRAT PHNG PHP SALICYLATE (Theo: A.H.Rump & H.Krist - Laboratory Manual For The Examination Of Water, Wastewater and Soil, 1988)

I. NGUYN TC - Nitrat trong mi trng acid mnh v nhit cao to ion nitronium (NO2

+). Ion ny phn ng vi salicylate to hp cht nitrobenzoic. Trong mi trng kim mnh, hp cht nitrobenzoic ny chuyn sang dng quinoid c mu vng, hp th quang 420 nm. Phng php khng b nh hng bi nitrit ( 2 mg/L), clorua ( 200 mg/L), st (< 5mg/L). Khong lm vic: 0,1 n 2,0 mg-N/L.

II. THIT BI DNG C - Cc thy tinh 50 mL - Bnh nh mc 25 mL

- Bp cch ct hay t sy 105oC. - Spectrophotometer (o c 420 nm).

III. HA CHT 1. Dung dch NaOH 30%: ha tan 30 g NaOH trong 70 mL nc ct. 2. Dung dch NaOH 2,5%: ha tan 2,5 g NaOH trong 100 mL nc ct.

Ch : Khng cha cc dung dch NaOH trong chai thy tinh nt mi! 3. Dung dch natri xalixilat (sodium salicylate): ha tan 0,5 g sodium salicylate trong 100 mL nc ct.

Khi bo qun trong t lnh, dung dch bn trong 10 ngy. 4. H2SO4 m c. 5. Dung dch gc NO3-N (100 mg-N/L): Ha tan 0,722 g KNO3 ( c sy kh 105

oC trong 24 h) trong nc ct v nh mc n 1 L (Bo qun vi 2 mL chloroform c 6 thng trong t lnh).

IV. QUY TRNH PHN TCH 7. Chun b cc dung dch trung gian v dung dch lm vic a. Dung dch trung gian (5 mg-N/L): 5 mL dung dch gc (100 mg/L) pha long v nh mc n 100 mL. b. Cc dung dch chun (dung dch lm vic): (0; 0,5; 1,0; 1,5; 2,0 mg-N/L).

S1 (0 mg/L) : 10 mL nc ct S2 (0,5 mg/L) : 1 mL dd. trung gian + 9 mL nc ct S3 (1,0 mg/L) : 2 mL dd. trung gian + 8 mL nc ct S4 (1,5 mg/L) : 3 mL dd. trung gian + 7 mL nc ct S5 (2,0 mg/L) : 4 mL dd. trung gian + 6 mL nc ct

8. Chun b mu + Nu mu c cha cht rn l lng, phi lc qua giy lc 0.45 m. + Pha long mu c nng NO3-N trong khong 0 ~ 2 mg/L 9. Cc bc phn tch

4. Tnh ton: Lp ng chun v tnh nng NO3-N trong mu hay mu pha long trc tip t ng chun.

10 mL dung dch chun/mu (cho vo cc thy tinh))

Thm 1 mL dung dch sodium salicylate, trn u

un cch ct hay trong t sy 105oC cho n kh

o quang 420 nm(*)

Lm ngui; thm 1 mL H2SO4 ., lc, yn trong 10 pht

Thm 8 mL nc ct dc theo thnh cc, lc u, ngui

Thm 7 mL NaOH 30% dc theo thnh cc, lc u, ngui

(*)Dng nc ct thit lp gi tr 0 (zero) khi o hp th quang

Chuyn vo bnh nh mc 25 mL, nh mc bng d.d. NaOH 2,5%


20

TRNG I HC KHOA HC HU

Khoa Mi trng H tn sinh vin: ________________________ Lp:________

Hc phn: Thc tp chuyn KTMT

____ ________________________________________________________ Thi gian lm th nghim:________________________

I. MC CH

(Nu mc ch ca bi TN)

II. TM TT C S L THUYT

(Trnh by vn tt cc ni dung yu cu ghi phn cui mi bi hng dn TN).

III. M T TH NGHIM

(Nu cc cng vic lm trn thc t theo trnh t; m t c tnh k thut cc thit b dng c chnh s dng. Khuyn khch s dng cc s , bng biu)

IV. KT QU TH NGHIM

(Trnh by cc quan st, cc s liu thu c, tnh ton c)

V. NHN XT

(Nu cc nhn xt v kt qu thu c; tho lun, gii thch cc kt qu; cc xut,)

___________________

Ch : Ton b bo co khng di qu 3 trang A4, tt nht trnh by trong 2 trang.

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