nghiên cứu ứng dụng tính chất kị nước của axít đối với quá trình nghiền clinker và tăng thời gian bảo quản xi măng

Sau niiv cac nha khoa hoc LicMi Xo da nghicn cu'u sii' dung nhieu loai phu gia ki nu''"c va cac dac dicMii ky ihual ciia xi mang ki nuac Irong vu'a, be long dicing trong cac cong Irinh \

BO GIAO DUG VA DAO TAG DAI HOG QUOG GIA HA N O I

T R U O N G DAI HOG KHOA HOG Tl/NHlfiN

DINH XUAN LOG

Ngliien ciiu ung dung tinh chat ky nuo^c ciia axit MDV

doi voi qua trinh nghicn clinker vii tang thori gian biko quiin xi inang

LUAN VAN THAC SY KHOA HOG HOA HOC

Chuyen nganh : Hoa vo ca

Ma so : 01.04.01

'L^JOt

Huong dan khoa hoc : TS Nghiem Xuan Thung

P(iS.TS.Phan Van 1 uong

Ua noi 2000

J

Xi maiig pooclang Khai iiiem

Thanh phaii hoa hoc ciia clinker xi m a n g

C a O SiO,

A l , 0 , Fe^O, MgO Kicm Thanh ph;1n khoang hoa ciia clinker xi inang pooclang Alit

Belit , Canxi Ahiniinal

cciii I1IZIIZZIIZZZ^^\Z^

I'ha tlmy tinh Qua Irnih hydrat hoa ciia xi mang Phan iVng hydrat hoa cua khoang Alit Phan ung hydral hoa cua khoang Belit Phan ung hydrat hoa cua khoang TricaxiAluminat Phan I'rng hydral hoa cua khoang Tetra caxi Fcroaluminat

Cac he so ca ban cua clinker xi mang pooclang

He so bao hoa voi LSF Modun Silic SM

Modun iihom AM Qua truih san xuflt xi mang pooclang Nghien xi mang pooclang

Thach cao Cac loai phu gia khac

O i c vcu to lien quan den qua trnih nghien

D o mill T\ le iiuo'c/ xi mang Thoi gian iiiiih ket Cirofiig do \ a mac cua xi mang

Su to;i nhiet khi doiig ran

1.8.7 D o ginm mac luc lini kho ban quan 20

1.9 Cac loai phu gia tra nghicn xi mang 21

1.9.1 T r o xi

-1.9.2 Phu gia Puzolan 22

1.9.3 Cac loai axil beo va chat hfru co khac 23

ChU(tng 2 Vai tro cua phu gia ky nirac doi vai xi mang 27

Chircyng 3 Cac phirang phap hoa ly nghien curu xi mang 34

3.1 P h a a n g phap phan tfch hoa hoc xac djnh cac thanh philn khoang

hoa ciia xi mang 34 3.1.1 Xac dinh lugng SiO trong xi mfing 34

3.1.2 Xac dinh ham lirgfng F e ; 0 , 35

3-1 -3 Xac dinh ham liraiig A i p , 35

3 1 A Xac dinh ham krcrng CaO ^ 36

3.1.5 Xac dinh ham lagng C a O tir do ' 37

3.2 Phirong phap phan tfch nhieu xa tia X 38

3.3 F^hucrng phap phan tfch pho hong ngoai 39

3-4 Phirong piiap phan Ifch nhict 41

3.5 IMian Ifch cap hat bang quang pho laser 43

l^han B Thac nghiem ^^

C hUitng 4 Nghien ci'ru anh hirong cua axit beo MDV den tfnh nang ciia xi

mang pooclang ^^^

4.1 Doi tintng va phirang phap nghicn cihi A^

4-2 Aiih hiring cua ham lirang phu gia dei] do min cua xi mang ^(^

4.3 Anh huang ciia ham lirang phu gia den do ky nirdc cua xi mang 50

4.4 Xnh hirang cua ham lirang phu gia den chat lagng xi mang khi

bao quan 5 I 4-4.1 £)Q hut am theo thai gian bao quan 51

4-4.2 £)Q \ on cue theo thai gian bao quan 54

4.5 Arih hirang cua ham lugng phu gia deii do deo lieu chuan ciia xi

mang _^

4.6 Anh hirang cua ham hrgng |)hu gia den qua lilnh dong h(.)c dong

ran cua xi mang ^^

4-7 Xiih hirang cua ham lirgng phu gia den cirang do cua xi m a n g 59

Chirang 5 Danh gia xi mang co phu gia ky nuac bang cac phirang phap hoa

ly hien dai ^

5-1 Phan tfch nhieu xa Ranghen

5-2 |>|ian tfch nhiet vi sai DTA

IMian ifch bang quang pho hong ngoai Phan tfch bang kfnh hien \i dien tir

Phan tich cap hat bang laser -^

Mo ddu

Xi mang la vat lieu quan Irong hang dau Irong nganh xay dung, chi'nh vi va)' nganh cong nghicp san xual xi mang dUdc coi la mol U'ong nhu'ng nganh mui nhon cua mol nii^c San Iticfng lieu ihu xi mang hang nam ciia moi nuac la mol Irong nhung chi lieu cho la ihay loc do phal Iricn kinh Ic ciia dal nuo'c

do

0 Vicl nam Irong qua Irlnh kicn ihicl dal nuac ,nhu cau sir dung xi mang cho xay dung hien nay la 18 Iricu Ian va duyc du doan lang Irung blnh khoang 10 - 15%/ nam Irong mUoi nam lai Dc ihu'c hien khoi lirong xay clu'ng lo 16'n Irong nhung nam lai, chiing la can lang dang kc khoi luo'ng xi mang va nang cao chal luang xi mang I r o n g dicu kicn lir nhicMi voi khf hau nhict doi nong am, mua nhieu, vice san xual, bao tiuan van chuycn, luu kho

laii ngay moi sir dung, nhal la xi mang \\i\ khong dong bao ihl van dc cai

Ihicn va nang cao chal hro'ng xi mang la ral buc ihiel Tu nhung ycu cau cap ihici do, vice nghicn cii'u va sil dung phu gia xi mang ki nuoc co mot vai Iro

ral c|uan Irong Do la mol giai phap khoa hoc ky ihual lam hiCMi doi mol so

liiih chal ciia xi mang, be long va vij'a be long iheo quan diem Uic dung cua niriV cV cac giai doan khac nhau Irong san xual va sir dung loai vai lieu nay Clu can mol luong phu gia hiru co* ral nho (vai phan nghln) cho vao khi

nghicn clinker, co ihe cai Ihicn va nang cao chal \via\\\i sii' dunu ciia xi man^^

() kicMi X6 lir nam 1947 - 1949 da nghicMi ciiu va chc lao diro'c xi manu ki nir(')c.dCMi nam 1950 da dira vao san xual cong nghicp Sau niiv cac nha khoa hoc LicMi Xo da nghicn cu'u sii' dung nhieu loai phu gia ki nu'(')"c va cac dac dicMii ky ihual ciia xi mang ki nuac Irong vu'a, be long dicing trong cac cong Irinh \a\' du'nu

0 nu6c ta tir tmoc tai nay co vai tac gia da nghien cuu sir dung phu gia ki nuac vai cac muc dich khac nhau nliu phu gia K 3 C S tir cac loai dfui khoang, dau thao moc nliam cai tieii tuili chat cua xi mang [ 3,16,17 ] Tliay dirge tarn quan trong va tinh thofi sir cung nJiu" muc dich cua van de neu tren

Trong pham vi cua de tai chiing toi khac sat , nghien ciiu^irng dung \oa\ phu

gia axit beo MDV vao xi mang pooclang Biit san nh^m dap li'ng yen cdu da n§u do

PHAN A

Tong quan

C H U ( ) N ( , 1: XI MAN(J POOCLANC;

1 1 Khiii iiiciii :

X i m a n g la ten g g i c h i m g ciia m o l nhcim h g p chat ket d f n h v 6 co\ cci kh;i

n a n g n g u n g ket, d o n g ran k h i ket hap v o i n u o v X i m a n g pooc l a n g la san

p h a m n g h i e n m i n ciia c l i n k e r v('yi p i n i gia thach c lo (3 - 5 % )

C l i n k e r o d a n g hat dirge san x i i a i b a n g each du vc n u n g c h o d e n k c l k h o i o I450"C/ h o n hgi") chi'ra da v o i va A l u m o s i l i c a t (dai set, x i lo cao )

r h a c l i cao c(i tac d u n g d i e i i c h i n h I h o i g i a n n i n l i ket cua x i m a n g t i o i i g k h i

n g h i e n m i n de d i e i i c h i n h Ifnh chat va ha gia thai h n g u o i ta c h o thcMii khoi'nig

L 5 ' / phu gia boat l i n h nhu" P u z o l a n , I r o , ( r c p c n k h o a n g 0,1 - 0.5';^ pini gia tro" n g h i e n uhir a x i l b e o , mo" d o n g \ a l , dfui thirc \a( va 10',^ phu gia l i o nhn c;it thanh a n h , da \ 6 i [ 7 |

X i m a n g dirge phat m i n h va san xua't tir dfiii the k y 19 tai A n h d o nhu'ng uu

(hiMU noi bal n h u c u o n g i]o c a o d o n g l i i n n h a n l i ucu xi m a n g pooc l;tng da

t i o thanh chat ket d f n h cjiian I r o n g nhal I r o n g \ a \ d u n g co' b a n

1 2 riuinli pliiin lioii hoc ciui clinker xi inaii^ | 9

D a y la y e n to cpian t r o n g nhal de d a n h gia chat I rgng c l i n k c i G o m co 6 o x i t

c h i n h :

1.2 1 C a O : c h i c m t(')'i 63 - 67 ^; va d u g v k\ hu u la C

C a O la oxit cpian I r o n g nhal dc' xi m a n g co chal u'Ong cao C a O ph;'ii lien k c l

hcl Mvi cac o x i t k h a c i i c i i hrgng C a O tir d o c o n 1; i a d a n g cpia lira sc l a m cho

da xi m a n g k h o n g on d i n h the Ifch g a \ tac hai c h o \ i m a n u L i r o i n : C a O lu'n

kcl Ion lam xi mang co cuong do cao, dong rfui nhanh nhirng khi dong ran lai loa nhiet nhi^u nen kern ben hoa

1 2 2 SiO, : chiem 2 1 - 2 4 '/r, ky hien S

SiO, lien kel voi CaO lao thanh khoang Silicat Cac khoang na\ ^'^'^ \ai Iro

qnyel (hnh tci'i cii'o'ng do ciia vua xi mang doin cii'ng Luong SiO, lien kcl l(Vn,vl vay xi mang co cuo'ng do Ion sau 2S nga) dong ran cham vl toa nhict nh(i khi d(ing ran ncn ben boa ho'n

1 2 ' ^ A 1 , 0 , chicm 4 - 8 '/r ky hieii A

A I , O j i e n kcl voi CaO va Fe,()^ tao khoang Aluminat va Aluminoferit canxi,

lam cho xi mang co cii'ong i]o phal Irie'n h'lc dilii ao sau chani dan Ihoi giim dong ran nhanh, nhiel toa nhieu, toe do toa nliiet Ion do i\n khi dong ran

kcm ben ho;i

1 2 4 F c O , chiem 2,5 - 3 '^, ky hien F

Fe,()^ licMi ket voi CaO tao thanh Feritcanxi 1 o a c Alumoferit canxi Ncii hrgng F e , 0 , hi'n, nhiel do ket khoi ciia jihoi lieu gi;'im, do nlvi't pha long nho

i.\c tao khoang trong clinkci Neu F e , 0 , ciua h n xi mang co l\ Irong cao

cunng iAi^ Ihap, dong ran cham, toa nhiel lha|), nhung ben hoa

I : 5 M g O tir 5 -6 %

Neu M u O > 5 - 6'f sc lam xi mang khonu on dinh the lich khi donu ran \i

no o tinnu d u n e tlich lan thnv tinh Pci iclaz (uion:-, Ca() lir do)

2 6 KiOm chicm 0.1 - \'/< kv hien KX)

Khi cho kiein van clinker thl mot phfin bay di va mol ph;1n o lai tronu clinkci (K.O > Na.O) Day la thanh ph:1n khong mong niuon \i n('> lam giani tto nhol ciia pha long, lam tang dinh bet va lha> doi lor do dong lan cua \i mang Kicm lac dnng voi SiO, lao gel silicat kicm co die licli Ion ga\ mat on dnih the lich, khong ben nii'6'c

Ngoai ra con co cac oxit khac n I n i T i O , - Mn,() !',() nhung co anh huong nho khong dang kfi toi xi mang

1 3 r i i n n h p h a n k h o a n g c u a c l i n k e r \ i niaiiji p o o c l a n g | 4 |

I 3.1 Alit ( ( \ S ): chiem 4.'S - 7 0 %

\)C\\ la khoang (juan Ining niiat cua clinkci ix) la dung dicli ran ciia

."^C/aO.SiO, CC) lan lAn ^ - 4'/r cac oxit khac Alit (C.S) lao Ihanh a nhiel do <

Tinh chat cua Alit trong xi mang:

- Cho \ i mang c(') cuo'ng do cao nhal sau 2 < ngay

- I h o i gian dong ket nhanh dong ran nhai h (sau C,A)

- Foa nhiet nhieu khi dong ran

- Khong ben Irong moi tiiiong Siinfat

\ } 2 Belil : chiem 20 - ^0'/ (C,S) ?clil la dung dich i;'ui cu;i

2Ca().Si(), CO tan lan 1 - 3'Y cac oxit kh:ic C,S (2CaO.Si(),) co nhicu daiii:

thh hinh: (/C.S , f^C.S , yC,S nhirng chi c6 da ig ( K \ S la c6 tinh chat kel

dinh dfi) la dang ngiroi ta lAt mong muon co

|iC,S gia b£Mi Ion lai a t" < 650"C \\C^S kho I6ng hop vi khi lam lanh i / C S ->

yCVS va tang the lich 10% lam tang clinker, yC^S khong co l i n h chA't kel dinh

do vay can |)hai tao on dinh (^C,S qua cac phiron:', pha|i sau:

- Hoa hoc linh Ihe: dua vao mol so oxil nhu" N; O P , 0 , , P>0 lam Ihay doi cau In'ic linh the, lam Ihay doi tuih chat ho;i ly ci a C,S

- Vai ly: nang cao ham luong pha long l i o n g clinker hoc chal la\ (K'.S ngan can sir chnyfen ihanh yC^S

- Nhiel: lam lanh nhanh vu'o'l qua nhiel do hien doi thu hinh \'i khi do c;ic

cA'u hue tao thanh rieng re khong kip li)[i ho|^ lai thanh dnng dich r;ui o nhict

do cao ncMi khong kip hich ra

Tinh chat ciia Belit trong xi mang:

Lam cho xi mang c() cuong do phiil tiien cham nhung sau 2S nga\ I hi gan bang C\S

- Thoi gian dong ket chain

- To;'i nhiel nho khi dong riin

- Ben trong m o i truong Sunfal

1 3 3 Canxi A l u m i n a ! : chiem 5 - 15%

La dung dich iTni cua C,A (3C\i() A L O , ) co tan lAn 1 - 27rCaO tuy theo

luong CaO C \ a che do lam lanh clinkei ma C; nxi A l u m i n a t c(i the o dang

C^A,C\A, T r o n g clinker xi mang chi'i yeii la C , A

'•' Tinh chal cua Canxi A l u m i n a l :

- Lam cho xi mang c(') cu'ong do ph;il tiicn nhai h nhung sau do h| chain l<ii

va khong h,nig C,S

- Thoi gian dowz kel nhanh nhal

- Toa nhiet nhieu khi dong rfin

- Khong ben Irong moi Irirong Sunfal

1 .3 4 Celil : chiem 1 0 - 1 8 %

La dung dich lAn ciia C^AF ( 4 C a O A i p , F e , 0 ; ) r o cac Ihanh phAn khac nhau phu thuoc vao phoi lieu va di^u kien nung luyen C^A.F; C , A F ; C,F

() day chii yeii la d A F

1 inh chat cua C,AF :

- Lam cho xi mang c6 cuo'ng do thaj") nhal

- Thoi gian dong ket cham

- Toa nhiel khi dong ran Ihap nhAl

- Ben trong moi Iruong Sunfat ho'n C,A

I .^ 5 Pha thiiy tinh trong clinker :

Do C^A, CjAF, C,F (V nhiel do cao - ^ hoa King - > lam lanh ~> lao thiiy tinh

Pha Ihuy linh co lAn MgO va cac tap chA't khac do do tuy che do lam kuih ma

|iha Ihuy linh nhieu hay fl Neu phix thiiy linh nh eii thl khi xi mang dong ran

se toa nhict nhieu

ra Tlurc Ic cho Ihay tham chi sau 4 nam \ a n con 15'r C,S chna iham LLKI

phan I'rng vi the cac hat xi mang va eac phirong ihap xii ly b^ mat cua mi co

y ngliTa rAi \on doi \ri\ toe do qua tilnh hidral ho;

1 4 1 Phi'ui irng hidral hoa ciia khoang Alit:

Alit lac dung voi niroc ngay a Ihoi diem nhao Iron xi mang \o\ niroc san

phAm tao thanh la gel- hidrosilical \ a C a ( O H )

2(3CaO.Si()0 + 6 H / ) -> 3CaO 2SiO,.3F , 0 + 3 C a ( O H ) ,

Muc do Ihuy hoa ciia Alit phu thuoc vao ly le N/K, lirang C a O co trong dung dich va nhiel do moi Iruong ihi cong Cac hidros lieat du'oc tach ra diro'i dang soi gan gioiig cA'ii true deo tobermoiit In" nhien, n^oai ra con c(i can tn'ic dang ong, dang lAm, dang linh the hinh kim vcVi c; c kich IhiKic khac nhau sir phAn bo khac nhau Chinh nhu'ng hidrosilical nav lao nen cu'ong do d;i cho xi mang

1 4 2 Ph;'ui ung hidral hoa cha khoang Belit

Khoang nay co 16c do Ihuy hoa chAm va tach ra it C a ( ( ) H ) hon so \'(vi C\S

Neu khi Ihi cong ly le N/X IhAj-) Ihl sir hidral hoa khoang nay khong co

Ca(()H), lAch ra Khi ly le N/X qua cao va qua irlnh nhao Iron manh thl co xay ra phan ii'ng :

C S + n H O -^ 2Ca(OH), -f SiO, (n - 2 ' H , ( )

loan bo c|u;i Irlnh duoc bieii dien qua so'do sau:

C , S ^ C , S H ->CSH

Iheo lien la ihAy C,S la mot khoang quan trong Iiong xi mang No quyc;'l diiih

den cuo'ng do ciia da xi mang, hon nfra lai rAl it i Ay ;inh hirong phu khong c(')

loi

8

Ban chn't kei d f n h ciia C a n x i Silicat la d o dac I f n h cAii l i n e m a n g t i n h the cua cac pha boat t i n h h y d r a t , tire la sir co mat ciia t a c k h o i In" d i e n SiO^ t r o n g cac k h o a n g cha c l i n k e r

T r o n g cac k h o a n g C^S, C\S sir cAn bAng hoa t i i c ua cac a n i o n O c h i la h i n h thifc T l i i r c le cac a n i o n nay chira d u o c bao hoa aoa t r i b o i cac c a t i o n H ' lAn

c o n g vao can l i n e l a m thay d o i I r a n g thai cAn b a n g hoa t r i K e l qua la m o t so ion C a ' * hi l h a \ the b(Vi ion H * ( ) t i a n g thai cAn b a n g cAu I n i c cua c l i n k c i

(tu'o'c sAp x e | i l a i cac l i n h Ihe d a n g s o i , d a n g o n z diroc h i n h t h a n h tao n c n

l i n h ket d f n h d o n g ran ciia x i m A n g , cac i o n C a ' hi dAy ra l a o nen C a ( ( ) H ) ,

1 4 3 i l i i ' u i l i n g h y d r a t hoa ciia k h o a n g t r i c a n x i a l u m i n a l

Kho.'ing C , A la pha hoal d o n g i i h A i ngay k h i I r o n xi m a n g vcVi luKrc c l u i n g dr

d a n g phan u n g tao I h a n h l i n h thd 1A|) p h u o n g C\A H,,

1 4 4 Phan l i n g h \ t l i a l hoa cua k h o ; i n g t e t i a c a n x i f c r o a l u m i n a t

K h o a n g n a \ thnc h i e n |)han u n g hydrat boa chAn h o n loc do h i t h a l ho;! c u i i u phu thuoc \ a o loc do Ihi c o n g h a m l u o n g C a ( O H ) , I r o n g d u n g d i c h Iv le

N / X sAn phAm c d the" la C \ ( A F ) f L hay d a n g kliAc, s o n g h i o n c d xu h i K i n g chuxCai t h a n h d a n g ben v u n g C , ( A F ) H „

4 C a ( ) A l , ( ) , F e , 0 , + l 2 H , 0 ^ 3 C a O A I , ( ) , 6 H , ( ) + C a ( ) F c , ( ) 6 H ( )

Hydro fciit iiAm lai Irong thanh |->h;1n cua xi mami con h \ d r o Aluminal sc l;i

dung voi Ihach cao nhir (V tien

1 5 Cac he so co ban ciia clinker xi niiing pooclang | 9 |

I 5 1 He so bao hoa voi LSF :

00 CaO LSF =

2.x SiO, + LIS AI,(), + 0,65 Fc,()

93 9s ';

LSF hicu hien long luxrng CaO cAn Ihict (.]r bao hao hoan loan c:\v oxil

kh;ic chi'i NCU la can co du luong CaO dc lien kcl hoan loan cac oxit SiO,, A 1 , 0 , , Fe^O, Mai khac jihai tianh lluia CaO tU do gay h;ii cho xi

mang | 9

LSF va SM lang se lam cho luong voi tu do lani' len LSF co anh hu'ong

den kha nang nung ciia clinkei

Sir lAng SM lam giam kha nang nung cua clinke do sir giam ham luong pha long va giam xu hirdng hinh thanh lop cola trong Id sir tAng SM cung dAn loi sird()ng ran va ciro'ng do xi mang khong dong nliAt phat trien cham Sir giam

SM cung (lAn den pha long tang, dieu nay c;;i thien kha iiAiig nung cua clinker va hinh thanh lop cola Irong 16

1 6 Qua trinli san xiiat \i mang poocaiig

Qii;i (luih san xuAt xi mAng pooelAng dirac thir( hien qua nhieu cong doiui

nen lieu \o\\ nhieu nAng hro'ng Sau dAy la so" do mot dAy chuycn san xuAt xi

mAng pooclang lai nha may san xuAt xi mang

Da voi May dap Kfio dong ninat so bo Ket chUa

w

p

May dong bao

'^ r Xual xi m^ng bao

Huih 1 So' do cong nghe san xuA't xi mang

1 7 Nghien xi mans pooclang

T h i r o n g n g i r a i ta n g h i e n c l i n k e r v a i cac l o a i phu da i^liu:

1 7 1 T h a c h cao

T r o n g san xuat x i m a n g viee dira t h e m t h a c h cao vao t h a n h phAn x i m A n g la

bAt b i i o c d i i n g de d\iu c h i n h thd'i g i a n d o n g rAii ciia xi m A n g LiVo'ng thach

cao dira vao phu t h u o c vao h a m l u o n g C , A , [ hii t h u o c vao d o m i n , h a m hrong kicMn cua c l i n k e r , vao m u c d o ket k h o i cua c l i n k e r L u o n g t h a c h cao dua vao lot iihAt k h o a n g 2 ^ 5 %

1 7 2 Cac loai phu gia khac :

I h u o n g c h i e m k h o ; i n g < 1 5 % de ci'ii t h i e n t i n h chAt xi m A n g va tAng l u o n g xi

m a n g

M u c d i c h cua cpia l i u i h n g h i e n la dal diroc \ i nAng c('> d o m i n t i c i i c h i i i i n

3 2 0 0 b l a i n e hoac lot cjua sang 4 9 0 0 16 \'a l i a n h cac b i e n d o i hoa hoc l a m gi.'im chat hrong xi m a n g , g i a m t o i da tieii hao n ' u i g l u o n g n g h i e n ( t r o n g c;ic nha m a y xi m A n g n a n g l i r a n g tieii Ihu c h o cac qua t i u i h n g h i e n Ihu'dng c h i c m t(Vi 40^^ ) ncn phai ap d u n g c o n g nghe n g h i e n thfc h ho'|') de gi;'im gia t h a n h san

|)hAin

1 7 3 -Cac y e n i d licMi q u a n den qua t i l n h n g h i c ' i :

a Do m i n : \'iec n g h i e n c l i n k e r t h a n h hot m i i d u o c t h i i c h i e n t r o n g m a y

n g h i e n b i do m i n phai dal d u o c kJKKing 2 8 0 ) - 3 2 0 0 c m 7g hoAc lot cpia

sang loai 4 9 0 0 16 Nhu" vay c l i n k e r d u o c n g h i c n tiVi luc l u o n g c o n lai l i e n

sang la k h o a n g 10 ^ 1 5 % N e u xi m A n g diio'c n g h i e n m i n cpia c u n g khouL' tot \'l \ i m A n g se bi co n h i e u va t o n n a n g \\\'< ng n g h i e n cu'ong di) cua \ i

m A n g t a n g k h o n g ty le v o i d o m m

13

b Kha nang nghien cua vat Heu : neu clinker cc- lironig Q S cao va LSF thA'p

se ra't kho nghien Ngoai ra cac yeu to v6 kich ea tinh th6, toe do lam nguoi sau nung, c6 hat clinker, che do u bro quan clinker se co anh hirang nhieu d6'n kha nang nghidn cua clinker

c Phirang phap nghicn (kin - ha), loai may nghien :

May nghi6n ha (nghi6n thang) thucmg tieu ton nang luong nghidn lan va khi nghi6n min hay gap phai vAn de bam dinli, von k6't kho cua cac locii xi mang tr6n b6 mat vAt nghidn, can tro qua trinh nghien Nen cac nha may lorn khong diing may nghidn ho ma d i n g may nghi6n chu trinh km , tiet

ki6m 10% nang Ivrong nghicn , giam bot cac vA'n de vi von ket kh6 Loai

may nghien thucrng diing hien nay la may nghien bi chu trinh km Vat lieu diroc giam kich thirdfc do sir va dAp, sir cha sat gifra vAt nghidn va vat lieu, hat min diroc hut ra truo'c mot phAn boi quat gio Luang vat lieu ra khoi may nghien duoc tach ra, phan ly, hat thi) tro lai may nghidn

ti6'p.V6i cong nghe hien dai nguoi ta ket hop may nghien bi va may dap

so bo nhAm mue dich giam tieu ton nang luong nghicn May nghidn bi thuong duoc ehia thanli cac ngan rieng voi ty le, loai bi dirge tinli toan cho phu hgp v6i tung ngan

d ) Cac chat trg nghidn : La chat dua vao lam tang kha nang nghi6n bAng each ngan can sir tao lop bam dmh tren b6 m i t vat nghi6n hoac lam phan tan vat lieu nghicn , hoac cai thien tinh chat cua xi mang ma khong gAy anh huong xAu toi tinh chat cua xi mang Chat trg nghien can de dat hieu qua tot chiem khoang 0,1 ^ 0,5% (tire 0,1 ^ 0,5 kg/ tan xi mang ) co the

tai)g nang suat nghien tir 10 ~ 20% Tuy hiei qua kinh te ma nguoi ta su

dung chat trg nghien nhu the nao Cac chat tig nghien thuong dung trong nghien xi mang la Amin acetat, ethylenglyeol, Hea2, DDA-7

14

1 8 Cac tinh chat ca \y hoa cua da xi mang va cac yen to

anh huiVng t('yi no

1 X 1 D o min :

Nhu tren da noi do min the hien miTc do nho c la cac hat xi mAng, do mui

cang nho toe do Hydrat hoa cang tang do dien tich be mal cua hat khining tang, do do sir tiep xilc voi nirdc cang Ion, lam ^ho sir kel tinh pha ran moi

d6ng dCni va de dang hon Tuy nhien do min qua nho se lam loc do hydial

hoa dicn ra nhanh lam anh hirong nhieu den tinh chAI co' ly cua xi mAng Vi

do mill nho se cAn rAl it nu6c nen be tong se hi co venh nhieu, do min nho

cung lam ton hao nang lugng nghien

1 X 2 Ty le niioc/ xi mAng ( N / X )

Ty le N/X la lugng luioc tieu chiiAin nhal dinh cAn Ihiet cho mot lugng xi

mang dcm dung de c() du do deo cAn cho Ihi co ig, tir do nguoi la tlm duoc

ty le nirdc/ xi mang toi Ihieii thuong la tir 25 ^ 3( '/<• theo trong hrong xi mang

I 1 I | Hon nfra hrong nirdc lieu chuAii cung phu thuoc vao do min cua \i mang Do min cang Ion Ihl ly le N/X cang nho Lugng N/X cung phu thuoc

\'ho thanh phAn khoang cua clinker Xi mang co ihanh phAn C\S Ion Ihi luong

nii'cVc tieu chu An Ion

1 8 3 riidi gian ninh ket

Khi Iron \i mAng \'(Vi niioc se xay ra jihan ung Ihuy hoa cua cac khoi'uig liong

xi mAng \ ii'a t;io thanh Iheo thoi gian sc mAl ('An tinh deo sau do \\o ncn ciVng ran \ a co the chiu lire dirge Ngirdi ta |4iAi hiet hai loai thoi gian ninh

kcl :

\5

- Thai gian bAI dfiu ninh kel : la thoi gian tir khi bAt dfiii Iron nude cho den khi vua mat tinh deo

- Thai gian ket thilc ninh ket : la thai gian tii khi Iron nude den khi \ u a cirng lai va cd the chiu lire dirge

Trong Ihi cong, chi tieu nay phai iiAm ro vl tAt ea cac khAii \'An chuyen, do

va dAm be t6ng phai tien hanh xong tiudc khi xi mAng bAt dfiu dong dAc, do

do xi mAng phai cd thai gian ninh ket du dai chi cac thac^ tac nay duoc hoan lAl Theo TCVN cung nhir tieu chiiAn the gidi 'hi thoi gian ninh kcl cua \i mang duoc xac dinh lir ho deo tieu chuAn banu dung cii vica voi kim c(') duo'ng kfnh Imin Thni gian bAt dAn ninh ket la khoang thoi gian In" khi bal

(lAu nhao Iron xi mAng vdi nirdc d^n khi kim vi^a cAm sAii 3S - 3 9 m m , yeu

cAu thoi gian nay khong nho ho^n 45 phut

Thoi gian ninh kei xong hay bAI dAii lAn chAc la khoang Ihoi gian tir khi nhao

Iron xi mAng vdi nude d€n khi kim vica cAm s Ui I - 2mm Thoi gian nay

khoang 104^12 gid L 4 ]

1 X 4 Ciidng do va mac cua xi mAng :

Theo TCVN 140 - 64 fl 1] mac cua xi mAng dngc xac dinh theo cuong do chiu lion cua 3 mAu vfra xi mang hinh dAm cd kk h thirdc la 4 x 4 x 16cm chc tao trrh6n hop 1 xi mAng : 3 cat va hrgng nude ti-Hi chiiAn (xac dinh bAng ban tian) diiong he 2X ngay trong dieu kicn lieu chi An mot ngay trong khu6n o ngoai kh6ng khi Am va 27 ngay sau ngAm trong uidc d nhiet do phong Tinh

tiung blnh theo cirdng do chiu udn cua 6 niVa mAu dem do Thuong cuong do

cua xi mAng phat trien khong dong deu, trong 3 ngay dAu cd the dat duoc 40

- 50 % mac xi mAng den 7 ngay thl dat duoc ( 0 - 7 0 % Trong nhiuig nga\ sau 16c do chAm dAn den 2X ngay moi dal diKvc mac yen cAii 'Tu\ nhien liong nhuim dieu kien ihiiAn loi thl sir ran chAc cua be lonn co the kco dai

16

hang nam va vum gap 2 - 3 lan ctrang do 28 ngay cua no va lang ihco quy lual logaril

Cirrmg do cua da xi mang va loc do ciing rSn ciia no phu Ihuoc vao ihanh phan khoang clinker, vao do min cua xi mang, do am nhiel do moi Iruong va Iht^i gian bao quan cua xi mang Toe do phal Irien eu5ng do cua cac khoang li'ong xi mang ral kliac nhau (dudc liinh bay 6 hinh 2)

4v

0 7 28 90 180 360 (ngay) Hinh 2 : Sic tang cudng dp cua cac khoang xi mang

1 - C,S ; 2 - CyiF ; S-C^S ; 4- C,A

Jvi day la ihay C^S co do lang cuong do nhanh nhal , sau 7 ngay no dal den

70%^ cudng do, 28 ngay sau do ihl cham lai Con doi vdi C^S chi Irong ihdi

ky dau (khi dal den 28 ngay ludi) ihl C2S co loc do phal Iricn cUOng do lai ral cham chi dal khoang L5% cudng do cua C^S Tlidi ky sau loc do nay lang len duoi kip va cd ihe vuoi ea cudng do cua C^S Con C^A ban ihan no c(') cudng

do ihap nhung lai phal Irien ral nhanh d ihd'i ky dau D() mm cua xi mang

17 TRUflGTAM^UUG_T^N,T>IirVlENi

tang thl cucmg do cua no cung tang do \6n tmiig blnh cua hcit xi mang la

40)im, sau 6 - 12 thang rdn chdc, chieu day thuy hoa kliong vugt qua 10 — 15).im Nhu vay se co khoang 30 - 40% clinker khong tham gia vao qua trinh ran chac va hinh thanh ca'u tnic cua da Tang do min ciia xi mang cd nghTa la tang muc do thuy hoa xi mang va nang cao cUong do cua no Theo ket qua thu dugc thl cir tang do min cua xi mang len lOOOcmVg thl cuong do cua no tang len 2 0 - 2 5 %

Do am va nhiet do moi trudng cung co anh hirong den qua trinh ran chac cua da xi mang VI giai doan dau cua qua trinh idn chac la thuy hoa De tao m6i truong Am, trong thirc te da dung nhung phuong phap khac nhau nhu tudi be tong, phii mun cua, cat ^m roi tudi nude hang ngay

T6c do cua cac phan ung gifra cac khoang clinker vdi nude tAng len cung vdi sir tang nhiet do Qua trinh ran chac cua xi man^ cd the dien ra d mot vung nhiet do rong : d nhiet do blnh thuong la 15 - 20%C, chuiig hoi (80 - 90"C), gia cong oetola (170 - 200''C) va tham chi ca 6 nhiiet do am Trong octola chi sau 4 - 6 gid la be tong cd the dat dirge cuong do mac ,c6n khi chung hoi thl cham hon den 2 lan De be tong xi mang cd the ran chac d nhiet do Am thirdng phai sir dung cac chat dien ly nhu CaCl2 , NaCI KJii do ndng do cac

chat tan trong nude tang len va nliiel do dong bang cua mx6c giam xudng

Viee bao quan xi mang trong mot thai gian dai mac du d dieu kien tot nhat cung lam cho cuoiig do cua no giam di, sau 3 thang giam 20%, sau 12 ihang giam 40%, do min cua xi mang cang lan thl do giam cudng do cang nhieu

Sau day la bang tieu chuAn mac cua cac mac xi mAng theo TCVN 2 6 8 2 - 9 2 [15 ]

18

Cac chi tieu

Gioi ban ben nen N/mm

Thoi gian ninh ket

- Rat driu khong so'm hon

(phut)

- Ket thuc khong cliani

hon (gio)

Do on dinh Ihe Ifch (Iheo

phuong phap salahe) mm

Luo'ng mat khi nung( %)

1 8 5 Su loa nhiet khi dong i;in :

Luong nhiCM loa in khi d(Mig lAn phu thuoc vao Ihanh phfin khoang vat do nun cua \i mang va ham Uioiig thach cao Luong nhiet phat la c(') loi cho viee llu cong be long vao mua lanh hoac mudn ch( he long ifm nhanh nhung khong CO loi khi thi cong vao mua nong Dac bi.-t doi vai cong tnnli co khoi

luong Ion (Vi nhiet (\o Irong Imig khoi he long co the len loi 4 0 C ) do d<', doi

19

vdi nhung cong trinh nay mot mat ngudi ta piiai chu y deii ky thuAt thi cong

1 16 '40

^5

224

224

I S 6 Do 6n dinh the tfch

Khi xi mang lAn chac the tich cua nd Ihudng tha / doi Dieu dd chu yen la do

SU" tiao doi nirdc giua ho xi mang va moi tru'dng (nude tir do va nude Irong

cac gel) Th6ng thudng neii rAn chAc trong khons; khi thl xi mAng bi co con Irong moi trudng nude thl khong bi co hoAc nd n 61 chiit Su' thay doi the tich Ihudng gay ra nhung hien tuong cd hai nhu" sinli ra ung siiAl gAy mil ne kei cAu Nguyen nhAn chinh gAy ra hien tuong nay la xi mang chiia nhung tap chAI CO hai gAy ra sir thay d6i the tich Idn nhir CaO; M g O

I - S 7 \)o giam mac luc lirii kho bao quan

Xi mang khi bao quan Inn klio lAu nliAt la tn ng dien kien thcvi lict nAng nong Am tliAp Ihnong xiiyen, se dAn tdi bi hiit An lam xay ra cjna trinh hydral

hoa va cacb(-)nat hoa, tao thanh ld|i mang tren be mAl hat xi mang Ncn dc lAu, dAn dAn se hi \6n cue dcnig ran chAc lam c lo hoal linh ciia xi m;ing bi giam di kha nhanh Sir giam boat tinh cua xi mang dAn \o\ Ihoi gian dong kcl

20

ch;)m, cuong do cua xi mang vl the cung giam nl i6u toi 30'/r neu de lan 3 - 6 Ihring

Hoat tfnh cua xi mang giam la do thanh phAn khoang C,A \ a C , A F nhieu do min cua xi mang cang Ic'rn thl sir hut Am cang nh; nh dAn uVi hoat tfnh gi;im

D o giam hoat tfnh cua xi mang hie luu kho hao quan thuong xa\ la hoi co chc li6n hydrat hoa va cachonat hoa :

Ca(()H)^ + C ( ) ; -> CaC'(), + H,()

CaS(),.2H;() + C,A + 9 H , ( ) -> C,A.CaSO, I 1 H,()

VA CaO + up -> ( a ( ( ) H ) ,

K,S(), + C a S ( ) , 2 H , 0 ^ K , C a ( S O ) , 3 H , ( ) C,A + C a S ( ) , 2 H , 0 + 1 6 H , 0 ^ C,A.3CaS(),.32M,()

thien Ifnh nang cua he tong Phu gia co nhidu I )ai khac nhau, co the l;i tro

ha\ hoal tfnh c(') Ihe o dang dung dich hay a d i n g rAn Cac chat Iro nghien

duoc dira \ a o lam tang kha nAng nghien hang c: ch ngAn can su tao Ic'vp h.ini dinh lien he mat \At nghi6n hoac lam phAn tan \ at nghicn, hoAc cai lien liiili tlral cua \i mang

21

Lirong chAI tro nghidn de' dat hieu qua tot khi dira vao nghien vc'ii clinkei

thirang a khoang 0,1 - 0,5% lugng xi mang da c6 the tang nAng suAt nghien

lir l()-20'/r

Cac loai phu gia thuong dudc dira vao trg nghien la :

1 9 1. Tro xi :

Gom C, S A, F chiem 95 - 96% chinh la cac khoang Irong clinker chua hao

hoa voi CaO : 30 - 35% LUong CaO nhieu thl \'\ eo hoat tfnh cao Thuong

SiO, lir 2S - 38% neu hrgng SiO, > 38% thl lam ^iam hoat tfnh cua xi

Khi xi lac dung voi nudc Ihl no khong the hien loal tfnh, nhung khi co chat kfch Ihfch thl xi the hien hoal tfnh ChAI kfch thf-h (V dAy la Ca(()H)^, sunfat si1a voi khi ket hgp v6i nirdfc thl se tao ra lofp m ing tren he mAl xi chAI kfch Ihich se |)ha vo l(y|i mang lam cho xi hoc 16 ho.it tfnh nhu' kho;ing clinkci Ngufri la dua xi vao nguyen lieu hoac lam p iii gia dua \ao khi nghicn clinker

Neu liiong xi dua vao khi nghien clinker < \5^/f xi mAng Ihl goi la xi mAng

pooclang Ihudng Con neu lucrng xi dira vao > I ^% hrong xi mAng Ihl goi la

xi mAng xi

Yen cAu clinker cd ham lirang C\S va C\A \on vl xi cfin chat kich Ihich va

ddng ran cham Ham luong voi tu do cd the tdi 5 - 6% vl :

C a O - h H , O ^ C a ( ( ) H ) ,

Xi mAng xi cd Irong luong rieng, do co ngdt do 'oa nhiet, do hcu lanh va gi;l

Ihanh nho hon so \'di xi mAng thirdng nhung luong IUKVC lieu chiiAn va su chui nhiet cao hon \i mAng Ihudng

1 *) 2 Phu gia Pu/olan:

I'll/Allan khong cd kha nAng ddng rAn nhung la e hat kfch ihich d()ng ran giai doan 2 va duoc danh gia bAng do hut \'6i : can;: hul nhieu voi ihi IKKU tinh cua Pu/olan cam: h'ln

")"»

Do boat tfnh a dAy chu yen do lirtvng SiO va Al , 0 , cd trong Ihanh phfin cua

F^izolan, luong SiO^ cang Idn thl Puzolan cang tot

Thudng ngudi ta dua Puzolan vao cung khi nghien clinker Luong Puzolan

dua vao phu thuoc vao thanh phAn khoang trong clinker Do hoat tfnh cua

Puzolan cd tac dung :

- fhai doan dAu : lam chuyen hoa cac khoang liong clinker

- Giai doan hai : Ca(()H)^ duac giai phdng ra phan i'rng vdfi eac cAu tu hoal Ifnh CO trong Puzolan

C a ( O H ) , + SiO^ + Hp ^ CSH,

Phu gia Puzolan duoc dira vao xi mang cd lac dung lam giam Irong hrong rieng cua xi mAng, ha gia Ihanh xi mAng va lam cho xi mAng cd t:ic dung chong ihAm tot hon

1 9 3 CYic loai axit beo vA chA't hfru co khac | 27 J

Cac loai axil beo la axil huu e a mach dai nhir : oleic, stearic, panmilic va chAI beo, cac loai xa |")hdng, bitum paraphin, amino axelal, etylen glucol, projiylen glucol TAt ea eac l(n)i phu gia nay duoc dua vao trong khi nghien

clinker se lam tang kha nAng nghien cua clinkei chdng sir bam dfnh you cue

Irong silo nghien, Irong cac may ddng bao lam cho xi mAng cd tfnh chdng bill nirdc cao xi mAng se lAu bi giam mac khi de tix^ng klio lAu ngay bao c|uan Uic la lam cho xi mAng ngAn chan duoc c)ua Irlnh tien hydiat hoa De

giiii thfch sir ngan chan qua Irlnh lien hydrat IK a do tren co sd nghicn cu'u

cua mlnh Mileston [ 26 J da dua ra quan diem giai Ihfch cua phu gia Inrii co" den c;ic nh(')m C;S C,A nhu sau:

Do cac nhom phAn tU hmi ca cd chira cac nhdm OH va C O O H luc la nhdm

hydroxy I \ a cacboxyl con goi la cac nhdm phAn ''ire Cac nhdm phan cue nay

cd Ifnh chAt ua nucVc eon cac gdc hydrocacbon kd cd Ifnh ki nude C\ac nhdiTi

phAn cue Ua nude la OH ' va C O O H cd kha nang phan Ung vdi cac ion kim

?^

loai M '" Irong hat xi mang de' tao nen cac vdng chelal Cac vdng chclat l;ii

c('> kha nang kim ham sU hydrat hoa cua khoang clinkei Do do cac lu^p chal

huu c(^ dUa vao la cac chat ddng thoi cd chua hai nh('>m f^hydrowl \ a

cacboxilal co kha nang kim ham tot han cac hop chat cln chua mol nlu'im

phAn circ la hydroxyl hay nhdm cacboxyl

Vf du : cac phan lU sau day duoc sap xep theo thu lU kha nang kim ham tpia Ulnh hvdral hoa

(,)ua kel i|iia nghien ci'ru ve vai lio uc che tpia tiinh hydial h();i cac kho;mg xi

mang cua axil huu c(^ Mileston da chi ra lAng klii tliciii d l ' ; lionn \{UUv.i

a\it glulamic 1 l O C H - ( C l l O l l ) , - COOH se c(') kha nanu lie chc Ion hon so

24

vdi glucoza : C^H^^^^^ Con doi vdi axit beo stearic so vdi axit glutamic,

glucoza thl axit stearic la tot hon ca

Trong cong nghiep xi mang, chat tro nghien tmyen thong la Trietanolamin:

N (CH2CH2 — OH),; T E A ; Etylen glycol (- OH CH^- CH.OH) va cac dAn xuat cua chiing da dugc sir dung tij" lau Trong ihuc te de tang tac dung trg nghien ngudi ta thudng dijng chung ciing vdi hon hgp cac chat hoat dong b^ mat khac

Ngay nay viee sU dung chA't trg nghien kha pho bie'n tren the' gidi va ngirdi ta

da tong hgp dugc nhieu loai chat trg nghien mdi, chiing chu yeu la eac hgj) chA't hfru CO* cd chua nhdm rugu da chuc va nhdm amin Ngoai tac dung trg nghien con cd tac dung tang nlianh sir phat trien cudng do xi mang chdng von cue va tang thai gian bao quan Ve hieu qua kinh te ky thuAt, nhln chung cac chi phf cho chat trg nghien dugc bij dAp bAng Igi ich dem lai do tiet kiem dien nAng, giam tieu hao bi nghien va cac chi phi san xuA't khac Boi vAy viee

ap dung cac chat trg nghien cd tfnh chat keo dai ihdi gian bao quan, tang thoi gian dir Iru xi mang dang dirccnghien cuu ap du ig tai cac nha may xi mang Idn

0 Viet nam chat trg nghien da dugc thu nghiem va ung dung tai mot sd nha

may thuoc Tdng cong ty Xi mang Viet nam [ t ] Sau dAy la ket qua ung

dung mot sd phu gia trg nghien tai cac nha may >.i mang nhu : Hoang thach, Bim son , Ha lien va Hai phdng

25

Trg nghien tang do linh dong

xi mang bot, d6 deo vira, tang cuong do ban dAu

Trg nghien tang do liiih dong

xi mang bot Trg nghien tang do linh dong

xi mang bot Trg nghien tang do linh dong

xi mang bdt, chdng dmh bi trong may nghien

Trg nghien tang do linli dong

xi mang bot,tang cudng do ban dAu, tang thdi gian bao quan

Noi ap dung thu nghiem

Tang nang suat may nghien %

cua xi mang doi vdi nude a moi giai doan BAt dAu tu khi nghien clinker den

khi van chuyen va bao quan, ciing nhu d thai ky lao hdn hgp vua be long Lotai xi mang cd dac diem ban che dugc tac hai cua nude ma kha nang ddng rAn thuy lire vAn blnh thudng dugc goi la xi mang ky nude [ 18 ] Khai niem

ky nude khong chi rieng vdi bot xi mang ma con doi vdi h6 xi mang va da xi mAng

Tir nhieu nAm nay a cac nude da ap dung chat huu co ky nude de nang cao

do ben cua voi nhu chat md, dau thuc vat va dong vat, va mot sd hdn hgp

khac deu cd tfnh chat ky nude Thai Lama da cho mau dong vat va md Ign vao voi, eon thai co Nga da dung phomat tuai, cay gai bam nho cung vdi hat gai, vo cAy thong va nhieu chat khac

Trong nhung nam 1930 - 1940 d Lien X6 va m.)t sd nude tren the gidi nhu Canada, Nhat ban da su dung rong rai phu gia la xa phdng, axit beo khong hoa tan trong nude Vi du nhu : da xuat hien tren thi trudng cac ten ggi khac nhau: serodil, serolit, hon hgp olein canxi \ a olein alumin vdi Canxi hydroxit Ngoai ra cung dung cac Ihanh phAm lir bitum, sap va nhua o dang huyen phu de che tao be tong va vfra Doi khi dt ky nude hoa cho san nham

27

be long ngudi la da diing each lam lien liep bang dung dich xa phdng phen nhdm Irong nud'c hoac dung dich paraphin Irong diclo elan Cacbonlelra clorua va cac ihanh phan khac

Sau nay lac gia : Khigherovic da nghien cUu va di den kel luan la can dac biel chu y den phu gia ky nudc va ky nud'c hoa Loai phu gia ihi'r nhai nlur paraphin axil stearic hoac mudi canxi ciia axil beo cd phan uV Idn khi Iron vcVi xi mang khong lac dung vdi nd ma Ion lai Irong dd d" dang hon hop co' hoc Lc:)ai phu gia ihu hai la xa phdng hoa lan cua axil beo, axil nhua, hoac axil dau m(') Tuy ban than nd khong ky nude nhUng lai lao ihanh chai ky nude do Uic dung hoa hoc vdi xi mang Loai phu gia ky nude hoa ihugc loai

chai cd chua cac phAn lU Idn phAn cue khong doi xiing va co kha nang hap

ien kcl manu

icn kcl ion Rhan cUc

l>Rang IrUgl

Hinh 3 : Can true lop cua mang

2S

phu Utn be mal ua nudc (nhu xj mang ) tuong tac vdi cac ion canxi va ma nhe cii, lao Ihanh U-At lir chal che dugc dinh hudng Nhung phAn lir nay gin dAu phan cue cua no vai vai Uie ua nudc la xi mang va khi dd gdc hydrocacbon quay m phia ngoai

cd lac dung lach nudc Tuong lac nay dugc Irinh bay nhu d hinh 3

Chiing la biei rAng phu gia ky nudc ihuoc loai chat hoal dong be mat, linh chal quan irong nhal la nhirng phAn lir cua chA't nay cd kha nang bj hAp phu iren be mat cua vAl ihe lao ihanh mol Idp mang rA't mong.Trong phAn tu cua cac chal nay gom nhdm phAn cue va nhdm hydrocacbon Nhdm phAn cue nay la nhdm hydroxyl OH ' hoac cacboxyl COOH ' cd linh chA't Ua nudc Con gdc hydrocacbon lai cd ifnh ky nudc Hay ndi each khac nhdm phAn cue

cd ai luc vdi nudc va vdi be mal ua nudc cua ihe rAn nhu hai xi mang Gdc hydrocach(^n (mach) cd klia nang lach nudc nhung cd khac la ai luc vdi dAu mo' va bitum Do dd cac phan lii ciia cac chat hoal ifnh be mat dirge goi la ''Ifnh hai mal" Quan diCm chung ve mal ly thuyet ihl viee lao nen mang hA^p

ihu cd ifnh chai ky nu'dc dugc dua li'cn ca sd cac cong Innh nghien cuu ciia

Rcbindc phal Irien lu ludng co dien ciia Langchie ve vice dinh hudng cac phAn iii hoal ifnh be mat Ircn hien dudng phan pha va do ky nudc lao Ihanh bdi Idp hap ihii (Hinh 3)

Tlieo nghien cuu ve hoa ly ciia qua Irinh luyen noi , Rebinde da neu i-a anh hudng dac biel va dinh vi hoa hoc ciia nhdm phan cue doi vdi sir dinh hudng hinh ihudng ciia day hydrocacbon [ 20 ] Sau nay ap dung luAn de nay khi nghien cii'u be long bot [ 21 ] Theo lac gia Khigherovich ihl khi lua chon diing phu gia ky nudc de ihu dirge xi mang ky nudc fl hul Am va kliong ihA'm

nude se co anh hudng deii ihdi gian dai bao quan ngay irong mdi Irudng Am

khong bi giam do hoal ifnh, dd la dc; Idp hap ihu duoc ca'^u lao lir nhung phan lii' dinh hu'dng Lao ihanh hang rao bao vc doc dao cho liing hai xi mang i-ieng

29

biet khi do 26c hydrocacbon moc len tua tiia a hat xi mang co tac dung bao

ve xi mang khong cho nii6c xam nhap vao

Tuy nhien, tinh chat khong tham nuoc cua xi mang khong dugc can tio viee

che tao h6n hgp \ua be tong bing cac phuomg phap thong thuomg Do do

khon^ the duns bitum thong thuons dugc mac dii bimm thuoc loai phu gia

ky nudc nhung khong phai la loai phu gia ky nudc hoa

De iron blnh thudng xi mang ky nudc vdi nudc va cot lieu, dieu can thiet la

man^ kv nuac khons duac dav dac va nd phai de dang bi pha vd trong qua

ninh che tao hon hgp \ai'a be long Ngudi ta da xac dinh dugc rAng mang bao

ve nen cac hat xi mang ky nudc cd cau lao dang "ludi", cac hcaV xi mang ky

nude tac dung vdi nude theo the tfch va bi bde trAn ra tren toan bg be mat va

khi dd mauR kv nude nav bi pha vd

Khi sir dung cac locai phu gia ky nudc hoa nhieu nha nghien cuu tren the gidi

da dp dung cac loai phu gia nhu axit oleic, axit nhua va dAn xuat ciia chiing

nhu : Pec thao moc, xa phdng hoa, viso!, dau md dugc oxy hoa va eac chat

Ions silic huu ca abietat natri

Xi mang k\ nuac dugc che tao bAng each cho chat phu gia ky nudc vao liic

nghien clinker Viee nay c6 Igi cho cong doan nghien la lam tang do min ciia

XI mAng dong thai tao cho xi mang cd dac diem la ft hut am trong dieu kien

bao quan va \an chuyen khong ihuan Igi (mua ndng ALm ) cung nhu tao cho

xi mAng cd nhung uu diem khac vdi xi mang thudng, tao cho hon hgp vira va

be tong cd do linh dong va tfnh de do cao

Xi mAns kv nude khdns nhuns: cd kha nans chdns vdn cue khi bao quan ma

con CO the nAng cao dugc tfnh hoat n'nh ciia nd Phu gia ky nude cd anh

huonii bien tinh den qua trinh kei tinh ciia chAi mdi tao thanh dans hvdrat, co

kha nans tao ihanh cau tnic hat nho tuans doi dons nhat ciia da xi mans Xi

mang ky nuac con cd tfnh chai deo do tfnh chai hap ihu va boi nan cua phu

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gia ky nude nen chiing cd kha nang loai trir kiem Viee sir dung xi mAng ky nudc se cai thien dugc linli de dd cua hdn hop /ua be long lam giam lugng dijng xi mang Xi mang ky nude lam giam toe do bay hoi nudc ti^ be long trong dieu kien khi hAu kho, ndng do dd nang cao do ben ciia be long

Be long dung xi mang ky nude cd dac diem la sir hiit nude va tham mao quan

It do hon hgp chat ky nude cd kha nang tao mang xung quanh hat xi mang, vdi nhdm mang dien gAn chat vao hat xi mAng va nhdm ky nude quay ra ngoai da lam giam kfch thude hieu dung ciia eac mao quan trong vua ngan chan sir xAm nhap cua nude vao trong eac Id trong

Tfnh chat tham nUdc giam di ciia xi mang ky nude la do do ddng nhAt ciia cA'u triic dugc nAng cao va chat mdi bao thanh du'gc kei tinh d dang hat nho, eCing nhu do cc) Idp ky nude trong chAi mdi tao tl*anh dang hydrat

Su tao ky nirdc ciia vCra va be long se giiip cho chung giia* dugc do Am trong thai ky dfiu ddng rAn Do dd giam dang ke do co ngdt trong khong khf kho

va do nd trong khong khf Aim, giii dugc cirdng do lien kei khi giam lugng xi

m a n g

Tfnh deo cao ciia xi mAng ky nudc cho phep giam lugng xi mang trong be tdng ngoai ra chiing eon cd tac dung lam giam sir toa nhiet cho xi mAng, tfnh chong xani thuc trong mdi trudng khoang ciia xi mAng cung lAng len id ret VI vAv xi mans k^ nudc da duoc nshien cii'u va sir dung nhieu Irons eac cong Irlnh thuy Igi [ 22,23 ]

Chung ta deu bict: voi Ltia hinh keo dai hon 3.000 km Irai dai lu vi luyen

8 \5 dC-n vT luyen 23"50, nuoc ta nam ^j,on trong vising nhiel doi gio mua,

nflng lam, mua nhieu, khi hau dm u6t gfin nhu quanh nam Mot nira phia Bac tir Ha Giang den Hue la viing khf hau nhict doi dang chuytin sang on doi, nen nu^ia mua keo dai tu thang 4 den thane 1 1 miia kho li:f ihan" 12 den thanu 3

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nam snu, tuy nhien do anh hudng ciia viing on doi nen trong nhung thang nay vAn eon cd mua nho gAy do Am cao Con mien Nam til Da Niing den Ca Mau thi ehia hai mua ro ret la mua mua va miia kho Do lugng mua Idn trong mua

mua ncn cac cong trinh xAy dung deu phai tarn ngirng thi cong, viee tam

ngi^rng va giam tien do thi cong eac cong trinh xAy dung se keo theo giam lugng tieu thu xi mang Trude viee giam lugng tieu thu xi mang hang hoa (ude deii 30 — 40% tdng san lugng xi mAng san xuAi hang nAm) Cac nha may xi mang ciia ta khong the cijng tam ngUng san xuAi hoac giam san luong san xuAi dugc Vay bien phap duy nhat la phai luu kho lau ngay, do nang ndng nhiet do len cao cd khi den 35 — 37''C, (hong kho bao quan nhiet do con tang cao hon nua) se lam qua trinh phan Ung tien hydrat hoa va eacbonat hoa lang nhanh Con khi mua nhieu lai lam cho xi mang thuong pham, nhai

la xi mAng rdi khong ddng bao se hut Am nhanh gAy vdn cue keo theo su giam mac nhanh khi bao quan

Viee dua phii gia ky nuo'c vao xi mang lam cho xi mAng chdng dirge sir hiit

Am va cac phan ling tien hydrat hoa, eacbonat hoa nay la mot giai phap huu feh rAt Ihiet thue, dam bao cho sir luu kho lau ciia xi mang ma khong anh hirdng den chAi lugng ciia xi mang

La mol nude dang phat trien, nganh cong nghiep san xuAi xi mang ciia nudc

ta Cling mdi ra ddi, trinh do ky thuat con non kem, cong nghe lai lac hau,

thiet bi khong ddng bo, eu ky Do do nAng lugn,^ tieu hao cho viee san xuAi

mot lAn XI mang kha Idn khien gia thanh san phi^m tang cao mot each khong hgp ly 40 — 50% nAng lugng cho san xuAi mot tan xi mang lai nam Irong

cong doan nghien clinker Vay giam dugc lieu hao nang h\-gn- trong cong

doan nghien clinker se la mot viee rAi biic xiic Khi cho phu gia ky nudc vao hie nghien clinker se cd lai:

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- Tang do min ciia xi mang

- TAng nang suat nghien clinker hoac giam thai gian nghien do dd giam tieu hao nang lugng va bi nghien

- Chdng vdn cue trong silo chua xi mang

- TAng toe do ddng bao

Ndi torn lai viee nghien cihi va sir dung phu gia trg nghien ky nudc trong san xuA't va sir dung xi mang cd nhieu uu diem noi bat ma xi mAng thudng khong the cd dugc Nhal la trong dieu kien van chuyen, bao quan va sir dung xi mang rdi d dieu kien thai tiet ndng aim, mua nliieu nhu nude ta

Hieu qua ciia phu gia trg nghien ky nude trong s.in xuat xi mang la gdp phAn tiei kiem xi mAng ddng thai nAng cao nang suAi lao ddng trong xAy dung va cai thien chAi lugng be tdng, dac biet la nAng cao hieu qua eiia vdn xay dung Thuc nghiem da chung minh khi sir dung xi mi ng ky nudc cho be tdng cd the dat dugc mot trong nhung ket qua sau:

1 Khi khong thay ddi thanh ])hAn be tdng so vdi xi mAng thirdng thi do deo ciia hon hgp be tdng ky nudc se Idn hon dac biet vdi be tdng ft xi mAng

2 Khi giu nguyen cudng do thiet ke , cd the giam ty le N/X do dd cd the tAng do dac chac, do khong tham nude cung nhu eudng do chiu lire ciia be tdng

3 Giam \ugng dung xi mAng trong betdng ft xi mang khi giu nguyen eu'dng

do ihiei ke ciia be tdng

Tlieo cac sd lieu thong ke ciia cac ca sd san xuat betdng d Lien Xd thi vice tiet kiem xi mang trong san xuat be tdng khi luong dung xi mang khong Idn hon 240 - 260 kg/nr cd the dcit dirge la 8 - 12% | 3 ] do dd cd the giam dugc dang ke lugng xi mang can dung

33

3.1 1 Xac dinh lugng SiO^ trong xi mAng | 10 |

Xi mAng sau khi xac dinh do Am dugc dem dung xac dinh ham lugng SiO, Nguyen lAc cua phirang phap nay la hoa tan xi mang bAng HCI dac

CaO + 2HCI ^ C a C b 4 - H,()

A l , ( ) , + 6 HCI -^ AlCl + 3 H / 3

F e , 0 , -h dHCI -> F e C I , + 3 H , 0 SiO, nam dudi dang gel nen de tianh hien tiigng <:e( tiia keo ngirdi ta Ihudng cho them mot lugng nho mudi amonicloiua \'ao, loc nra ket tua nhieu lAn, cAn nung den tigng hrgng khong ddi Xac dinh cAn khong tan bAng each ngAm ket lua trong dung dich HF 4 0 % cho bde khoi tren bep dien deii kho Nung den khoi luong khong ddi Ham luong SiO duoc tinli theo cong thiic:

( a ' - a ) 100 |(

'/r SiO, =

m iOO - W

34

â long khoi lugng ket tua cua Si02 va can khong tan (gam)

a : khoi lugng ba con Kai sau khi thu do tinh khiei (gam)

m : khoi hrgng mAu (gam)

W: % đ Am

3 I 2 Xac dinh ham lugng Fe,(),[ 9 J 3 J 4 ]

LAy lurdc loc lira ciia qua Irlnh xac dinh SiO;,de xac dinh ham hrgng F e O , Tat c;i luong F c * duoc chuyen thanh Fe""^ hang iiidropeoxit

2 Fế + H / ) , + 2 H ' -^ 2 Fé" + 2 H , 0

Them axil snnphosalisilic va di6u chinh ITl dung dich den khoang 1.5 - 2

dung dich co mAu do sAm cua phíic sat sunphosalisilic chuAn F e ' bAng dung

dich FT3TA 0.01 M cho den khi dung dich chuyei,i tir mAu do sang vAng lóm

I lam luong F e / ) , dugc Inih Iheo cong thiic :

(),()()0798.5 V

% F e , 0 , = ^i= 100

m Voi:

V : thé lich dung dich EDTA 0,01 M

().()()()7')8.'^ : do chuAn cua F e , 0 , lii(tng ling \ d i I ml tlung dich EDTA

0.01 M

m : khoi hrgng mAu dem phAn tfch (g)

^ I } Xac dinh ham luong AI,C),[ 9.13.14 ]

ỊA> nuoc loc Irong t|iia trinh xac dinh ham liinn : Fc,(), Nhom dune l.kh la khoi c;ic ngti\en to khac bAng kiem manh

2 F e " 4 H , ( ) , + 2 H ' ^ 2Fe + l l , ( )

3S

Fe-" + 3 0 H -^ Fe(OH), AP' + 4 OH -^ AlO, + 2 H , 0 Ca^" + 2 ( ) H -^ Ca(OH)

M g ' " + 2 0 H -> Mg(OH)^

Loc Ufa ket lua nhifiu hin tao phi'rc nhom coiTiple ;onat

Ar^ + H^Y^ -> AIY + 2 H ' Tlicm chi thi xylen da cam, dieu chinh PH den 5 - 6 giai jihong EDTA khoi phuc nhom complexonal bAng NaF dung dich co man vang, diing dung dich Zii(C"H,C()())_, 0,02-5M chiiAn do lugng EDTA lirgc giai phong ra cho den khi mail dung dich chuyen tir man vang sang h nig ham lugng Al,(), dugc Ifnh theo cong lln'rc :

(),()()I2745A^K

% Al,(), = 100

m

Vdi V : the' tfch iliing dich Zn(CH,COO)2 ().025M da sir dung

K : he so nong do giua dung dich EDT/, 0,025M va

Z n ( C H , a ) ( ) ) , 0.025M

0.001 2745 : do chuAn cua AljO,i'rng voi I ml dm g dich Zn(CH,C()0)_,

0.025M

m : khoi hrgng mAu dem phAn tfch (g)

3 1 4 Xac dinh ham lugng CaO[ 9.13.14 ]

Dung IUKVC loc lira trong qua trinh xac dinh SiO, xac dinh ham luong CaO C"a * va M g ' ' dirge tach ra khoi iigii)en to khac h;mg Amonilndidxit

Fe'* + 3NH,OH -^ Fe(()H), 3 N H /

36

Ar^ + 3NH,OH -> AI(OH),+ 3 N H /

phan i'rng dugc dun soi d 60 - 70''C trong 45 phut cho amonihydroxit du

bay hoi bet, loc nra ket tua bang dung die i amoni Nitrat cho hel CI

Them KOH vao den khi PH = 12, tiep den cho 2ml KCN 0,5IVI va mot li

chi thi fluorexon ChuAn bAng dung dich EDTA 0,01 M cho den khi man huynh quang xanh vang cua dung dich chuyen sang man hong

Flam hrgng CaO tfnh theo cong thirc:

0,00056V

y/o CaC) = • • *^ 100

m

Vdi V : the tich dung dich EDTA 0,01 M da sir dung

(),()()056 : do churin cua CaO iTng vdi 1ml dun ^ dich EDTA 0,01 M

m : khoi hrgng mAu dem phAn tfch (g)

3 I 5 Xac dinh ham lugng CaO lir do [ 5.13 ]

Diing dung dich iirgu Glyxerin da co chi thi ph Miolphtalein hoa tan CaO tir

do trong xi mang de tao thanh canxi glyxerat ChuAn canxi glyxerat bAng axil benzoic 0,1 N cho den khi niA't mau hong the ) phan ung :

<^"H-(>H C H , - O - C a - O - C H

2CH - OH + 2Ca() — > CH - O H CH — O H + 2 H ; O

<^" -^>H C H , - { ) - ( a - O - C H

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