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IXIGHIEIM C i i u cdiVG I M G H £ S A Y D U O I V G T H L ) CdlVG TREIV IVIAY SAV THUIVIG QUAY
Nguy&n T i n ThinhS Tdn Thdt Minh^
T6M TAT
Say ducmg dcing vai tro quan trcMig trong san xu;il ducmg. Nghidn ciiu cAng ngb^ s£iy duong tr^n may say thiing quay Goai tiiiet bi thich hrrji s.iy duini^j; cr quy mo nho va vua) nhciin muc dich tim ra mpt ch€' dc) say thich hcri) cho inot san pliAni co ch.it knmg cao, tieu thu it nang lucTug va thcri gian say la ngan nhat. Cac thong s("i chinh anh hucing don cjua tnnh say va mirc anh hurmg cua chiing sir dung trong nghien ciiu la:
Nhiet do tac nhAn say i'\ CC)(7() 80°-9() ); tc)c dp tac nhan sfiy V On/s) (1-2-3) va tdc d<i vong quay ciia thung n (vong/phiit) (2-4-6). Bang phirong phap thi,rc nghidm lim tdi im, da xAy diyng durrc phuong trinh toan hc)c hdi quy bae hai: Y = 16.73- 0,19X|-0.21X,- 0,37Xi'- 0,34X/- 0.21X/ va d.1 xac dinh ducrc be? tb6ng sd trii uu ciia qua trinh la t", = 77,5°C; V = 1.7 m/s; n = 4 v/p, san phfim dat chA't luc,mg va hidu qua kinh t^ cao vrri thai gian s.iy la T = 16,7(S phiit. Mai khae dr- tai da thi^t k^, ch^ tao dur;c 01 may say thiing quay hoan chinh CO kha nang tiic'^n khai vao san xuat. May Uiich hc^p cho cac ccr scr san xuat ducVng ci quy mo vira va nho va co the say dircrc nhic'u loai san pham kh.ic nhau nhu ehe, ca phd. thuoc la. cac loai hat lucmg thuc va cac san pham heia CIUCTC, v.v...
Tir khoa: .Kiy dm'nig, may s.iy thiing quay quymd nhd.
LDATVANDE
Cong nghd say ddng vai trd quan trgng trong san xuat nhieu loai sin pham khic nhau. Say khong nhiing lim tang thdi gian bao quan. ting do ben co hgc, giam khdi lugng chuydn chd m i cdn lim ting gii tri vi chat lugng ciia san pham. Trong eong nghd sin xuat dudng d nucrc ta hidn nay, d cic nha may Icin, dudng dugc say trdn cic thiet bi sing rung - soi, cdn d cic eo sd sin xuat nhd dudng hau nhu khong qua khiu say m i ddng bao bin luon, tuy ring do am trong dudng cdn k h i Icin (2-3%); vdi do am niy, qua thdi gian bao quin dudng se bi ldn men chua, vi khuan cd dieu kidn boat dgng din den chat lugng sin pham giam siit, gii thinh sin pham vi the cung giim theo. Vide nghidn cun, thidt kd chd tao thiet bi vi cdng nghd sdy don gian vcii kinh phi khdng nhidu, dd van hinh vi cd thd sdy dugc nhidu loai sin pham khie (sau vu dudng) dd trang bi cho co sd sin xudt phu hgp Ii vide can thidt nhim mang lai hidu qua cao cho cic sin phdm nong nghidp ciia ngudi nong din.
I . PHUONG PHAP NGHEN CUU VA THET Bj THJ NGHI$VI
1. Phuong phip nghidn ciiu
Qui trinh nghidn ciiu sii dung cic phuong phip nghidn ciiu sau diy:
Phuong phip thuc nghidm trdn thid't bi; phuong phip quy hoach thuc nghidm tim tdi uu; cic phuong phip phan tich xic dinh tiiinh phan, do am vit lieu.
2. Thidt bj thi nghidm six dung cho qui tiinh nghidn ciiu
Thidt bj say thiing quay dugc thidt kd, ehe tao co day dli cac chiic ning. eong dung, cd the thay doi ducjc cac thong sd mdt cac chinh xic cho nghidn ciru nhu nhidt dd (Dieu khien tu dgng), tdc dd tic nhan say (Dieu chinh bing ning suit cua quat). tdc do cua thiing quay ODieu chinh bing tdc do cua hop giam tdc). So dd nguydn Iy lim vide ciia thiet bi say dugc thd hien d hinh 1.
I 4 ,_ O t
000000!
' Dai hpc Vinh
^ Dai hoc Bach khoa Ha Ngi
Hinh 1. H^ t h d n g sdy thiing quay thuc nghidm I quat; 2. budng nhiet luong; 3. tii dieu khien; 4.
nhidt kd tiiuy ngin dieu chinh cdng tie tiep xiic; 5.
phdu cip lieu; 6. binh ring din dpng; 7. thung quay, 8. vanh dai; 9. nip thao lidu; 10. khimg doth ting; H ddng CO din dpng thung quay; 12. hop giam toe; ll eon lin.
Nguydn ly lim vide ciia thid't bi: 6 mdi ehe do sdy didu chinh tdc dg quay ciia thung (n-v/p), t^c do ciia tic nhan sdy (V-m/s) va nhi^t dd tic nhSn
KHOA HOC CbNG N G H £
siy (t"s- C) d gia tri nhat dinh. Do am cua vat lieu miu sic san pham dugc ghi vio bang cho tiing mau say (Dudng kinh tring) cung duoc dieu chinh theo say. Cic mau say tiep theo dugc tien hanh tucmg tu.
ydu cau ciia tiing thi nghidm.
Khi tidn hanh tiii nghidm. dau tien cho tilling quay (Phia ti-ong thinh tilling cd gin cic cinh ning vat Ueu nghidng tiieo mgt gdc nhat dinh). tiep ddn cho quat chay vi cudi eiing ddng eau dao cho bg phan cap nhidt (Caloriphe) boat dgng. Khi nhiet dg tic nhin say dat yeu cau. cho dudng cin say vao phdu 3 (Chii y dudng phai dugc lam toi). Qua trinh say dugc tien hinh tii khi dudng vio den khi dudng ra khdi thiing, khi dudng dugc cinh ning ldn rdi dd xudng thi khi dd dudng am sd tidp xiic nhieu nhat vcii tie nhin say, lim cho am bay hoi v i thoit ra ciing tic nhin. Ra khdi thiing say sin pham dugc cho vio bao huge kin vi dua di xic dinh do am cudi. Say thiing quay li qui trinh lien tue, vide lay mau ndn lay lam 3 lan eho mdt me say de dam bao do ehinh xic khi xic dinh do am. Cic ket q u i thi nghidm: Nhidt do tic nhin say (t",-°C). tdc do ciia tie nhin say (V-m/s).
tdc do quay ciia thiing (n-v/p), thdi gian say (x). dd am dau vi do am cudi cua vit hdu. nhung thay ddi
Mi. K ^ QUA NGHiN CUU
Bing cie tiii nghidm so bg d i xic dinh dugc viing inh hudng ciia 3 ydu td trdn li:
Nhidt do tic nhin say r,(Xi) = 70 - 90°C.
Tdc do tic nhin sdy V(X2) = 1 - 3 m/s.
Tdc do quay ciia tilling n(X3) = 2 - 6 v / p h . Va cac miic tuong img cua chung (Da dugc m i hda: X muc dudi; X" mire trdn; X" miic tim):
Xi = t, = 70°C ; X," = t„ = 80°C ; Xf = tz = 90°C X2 = Vl = 1 m / s ; Xa" = Vg = 2 m/s ; Xg* = V3 = 3 m / s
X3 = Ul = 2 v/p ; X3 4 v/p ; X3* = n3 = 6 v/p
Tidn hinh tiii nghidm (Mdi thi nghidm say 2 lan) theo ma trin quy hoach thuc nghidm trdn vcM do am trung binh ciia vit lidu sdy cd dinh 2%, gdc nghidng thiing 2°, ta cd ket qui thdi gian say cho mdi thi nghidm khi san pham dat do am ydu cau W = 0,05% - 0,07% (Li do am cd the bao quan liu dii).
TN 1 2 3 4 5 6 7 8 9
Xi +
+
+
-t-
0
X2 -1- +
+ +
0
B
X3 + + + +
0
ang 1. Isi
X1X2 -1-
-1- +
+
0
lati-inti
X1X3 -(-
-1-
+
-H
0
lucngh
X2X3 -t- +
-1-
+
0
idm v i k
X1X2X3 +
+
+ -t-
0
:dt qua thi nghidm
Yi
15,1 15,0 15,9 16.1 18.2 17,9 17,6 18,5 16,7
Y2
14,9 15,4 15.7 16,3 18,5 18,1 17,5 18,8 16.5
Y 15.0 15.2 15.8 16,2 18,35
18,0 17,5 18,65
16.6
w(%) 0,066 0,071 0,070 0,069 0,061 0,068 ' 0,067 0,065 0,060 Q diy him muc tidu ciia q u i trinh l i thdi gian
say CTinh bing phiit). Thdi gian sdy dugc quyd't dinh bdi 2 yd'u td: Do am vit lidu cudi v i chdt lugng sin pham. Ddi vdi dudng d nhidt do say <100°C thi cic thinh phan khdng thay ddi, do viy chdt lugng dudng 0 diy chi bi^u hidn qua do tring v i do toi cua nd, cdn do am cua sin pham dudng duoc gicM han trong khoang W = 0,05% - 0,07% 0 ti-dn, khi sdy dd'n do am niy ta cd tiie dimg q u i trinh say.
Tir cic kd't qua thi nghidm ta lip bang ma trin tiiuc nghidm ba yd'u td v i ket qua tiii nghidm nhu sau (Bangl):'
Tli phuong trinh hdi quy tdng quit him bic
nhdt
Y = bo -I- bjXi -I- b2X2 -I- bjXa -H bi2XiX2 -1- biaXjXa + b23X2X3 + 0123X1X2X3
Sau khi tinh cic hd sd hdi quy vi thay vio phuong trinh trdn ta cd phuong trinh nhu sau:
Y = 16,84 - 0,275Xi - 0,41X2 - 1,29X3 + 0,021X1X2 -^
0,025X1X3-0,04X2X3
Kidm tra su cd nghla eua cic he sd hdi quy v i loai bd cic he sd khdng cd nghla ta cd phuong trinh mdi:
Y = 16,84 - 0,275 Xj - 0,41X2 - I.29X3
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 2/2012 57
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Kiem tra tinh thich ling cua phuong ti-inh hdi quy nay tiieo chuan Fischer ta tiiay cac bidn khcing dge lip vdi nhau, phuong trinh khong tiiydn tinh, do viy phuong ti-inh hdi quy bic mot ti-dn khong tucmg hgp vbi biic tranh thuc nghidm. Vi vay, trong trucmg hgp nay phai tien hanh giai bii toan tim tdi uu Irc'ii theo phuong trinh hdi quy bic hai.
Him hdi quy ciia quy hoach thuc nghidm bae hai cd dang:
.x! +
Vdi phuong trinh hdi quy bic hai 3 ydu td cd dang:
Y = bo -t- bjXi + b2X2 + h^3+ bi2XiX2-i- b23X2X3+
bi;P(iX3+b„X,2+b22X2^+b33X32
Vi ma trin thuc nghidm cdp hai 3 yd'u td:
sti 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
T 70 90 70 90 70 90 70 90 92 68 80 80 80 80 80
V 1 1 3 3 1 1 3 3 2 2 3.2 0.8 2 2 2
Bang 2. Ma trin thuc nghidm cdp hai 3 n
2 2 2 2 6 6 6 6 4 4 4 4 6,4 1.6 4
Xi
+ + + - +
-Hl.215 -1.215
0 0 0 0 0
X2
+ +
+ +
0 0 +1.215 -1,215
0 0 0
X.)
+ + + +
0 0 0 0 +1,215
-1,215 0
ydutd
X1X2
+
+ +
+
0 0 0 0 0 0 0
X2X3
+ +
+ +
0 0 0 0 0 0 0
X,X3
+ +
+ +
0 0 0 0 0 0 0 Tu cic kd't qua thi nghidm ta lip bang 3.
Bing 3. Kdt qui thi nghidm
stt 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
X i
-1 1 -1 1 -1 1 -1 1 1.215 -1.215
0 0 0 0 0
X2
-1 -1 1 1 -1 -1 1 1 0 0 1.215 -1,215
0 0 0
X3
-1 -1 -1 -1
0 0 0 0 1,215 -1,215
0
Yi
18.5 17,6 17.9 18.2 16.1 15.9 15.0 15.1 16.0 17.4 15,4 17,8 14,0 18,5 16,4
72
18,8 17.4 18.1 18.5 16.3 15.7 15,4 14,9 16,2 17,6 15,5 18,0 14,1 18,7 16,8
s;
0.045 0.02 0.02 0.045
0.02 0,02 0.08 0.02 0.02 0,02 0,005
0,02 0,005
0.02 0.08 0,44
yu
18.65 17.5 18.0 18.35
16,2 15,8 15.2 15.0 16.1 17.5 15,45
17,9 14.05
18.6 16,6 250,9 Tinh toin cic hd sd hdi quy ta cd cic gia tri:
bo = 16,73; bl = - 0,19; h^ = - 0,21; ba = - 0,1;
bi2 = -0,19; b23 = 0,125; h,^ = 0,025; b„ = - 0,37;
b22 = -0,34; b33 = -0,24
Kiem tra str cd nghia ciia cac hd sd hdi quy ta loai bd cic hd sd khdng cd nghla Ii: h^, bi2, b23, ba
Thay cic hd sd hdi quy cd nghla vio ta co phuong trinh hdi quy bic 2:
KHOA HOC C 6 N G N G H I
Y = 16,73 - 0.19xi - 0,21x2 - 0,37x,2 - 0.34x2^ - 0.21x3^
Kiem tra tinh thich ling eiia phuong trinh hdi quy nay theo chuan Fischer ta thay ring phuong trinh hdi quy niy tuong hgp vdi biic tranh thuc nghidm. Tii phuong trinh niy ta cd nhin xet:
Thdi gian say trong viing thuc nghiem phu thuoc phi tuyen vao nhiet do tic nhin say. van tdc tic nhan say va tdc do quay cua thiing say.
Thdi gian tdi uu dugc xic dinh bing cich xac dinh circ tri ciia him hdi quy bic hai.
Cac he sd tuong hd trong phuong trinh hdi quy khong tdn tai cluing td cac yeu td: Nhiet do. tdc do tic nhin say v i tdc do quay ciia tiidng anh hucmg dge lap ldn thdi gian say.
Xic dinh cic gii tri tdi uu (Tim cue tri ciia him bae hai):
Tim cue tri ciia him sd tren theo phuong phap giai tich ta cd:
+)Y,i=-0.19-2.0.37xu,, = 0
=> Xit „ = -0.25. Viy nhidt do tdi uu T = To + A-rXit.^
Trong dd Aj li do chdnh lech nhidt do tii gii tri tim den gii tri bidn trdn v i ducri (Ax = lO^C)
=>T= 80+(-0.25) 10 = 77.50c + ) Y ^ =-0.21-0.37.2x2,^ = 0
=> X2tu = -0,3. Viy tdc do tic nhin say tdi uu : V =
Vo + Av X2t„
Trong dd Ay li dd chdnh lech tdc do tic nhin say tii gii tri tim den gii tri bidn trdn v i dudi (Ay = 1 m/s)
=>V=2+(-0,3).l = l , 7 m / s +)Y,3 = -2.0,21x3t„ = 0
=> X3H, = 0. Viy gii tri tdi uu cua thong sd X3 chinh li gii tri sd vdng quay eua thiing tai tim ciia thi nghidm (n = 4 vdng/phiit)
Tir cic gii trdn ta xic dinh dugc thdi gian sdy tdi uu l i y = 16,78 (phiit).
Nhu viy, tir mo hinh cua q u i trinh sdy li phuong trinh hdi quy bic hai:
Y = 16,73 - 0,19xi - 0,21x2 - 0,37xi2 - 0,34x2^ - 0,21x3^
D i xic dinh dugc ehe do sdy dudng tdi uu ti'dn miy sdy thung quay vdi cic thdng sd cdng nghd:
Nhidt do tie nhin sdy: T = 77,5"C.
Tdc do tic nhin say: V = 1.7m/s.
Tdc do vdng quay cua thiing: n = 4 vg/ph.
VcM thdi gian say t = 16.78 phiit.
IV. KET LUAN
Nghien ciiu eong nghd say dudng trdn miy say tilling quay d i cho ket qua sau diy:
1. D i nghidn ciiu, chd tao dugc 01 thidt hi say thiing quay dd nghidn ciiu eong nghd say dudng (Cic tinh toin khong trinh biy d day). Thidt bj cd the didu chinh tiiay ddi cic thong sd mgt cich chinh xic cho qui trinh nghidn ciiu nhu t"„ Y^J"^', n^^^ Thidt bi cd thd ling dung vao san xuat vcM ning suat 200-300 kg dudng/h.
2. Da xiy dung dugc mo hinh toan hgc cho qua trinh say:
Y = 16,73 - 0,19xi - 0,21x2 - 0,37x1^ - 0,34x2^ - 0,21x3^
Vi tli phuong trinh toin hgc hdi quy thuc nghidm niy di xic dinh dugc cic thong sd tdi uu co ban ciia qui trinh li:
Nhidt do tic nhin sdy: T = 77,5*'C; tdc do tic nhin say: V = l,7m/s; tdc do vdng quay ciia thiing: n
= 4 vg/ph.
Thdi gian say (Him muc tieu ciia qui trinh) ung vcM cac thong sd tdi uu trdn li x = 16,78 phiit cho sin pham tring, dep, toi vi cd do am w = 0,061%.
3. Thiet bi say thiing quay li thiet bi thich hcyp de say dudng thu eong cung nhu say ducing d cic co sd sin xuat quy mo nhd vi vira, ngoii ra thiet hi cdn cd the sdy duoe nhieu loai sin pham khic nhau trong nginh eong nghd thuc pham vi sin pham cua cic nginh khic.
T A I UEU THAM KHAO
1. Nguydn Vin May, 2002. Ky thuat siy ndng sin tiiucph^. NXB Khoa hgc - Ky tiiuit HN.
2. Nguydn Minh Tuyen. Quy hoach tiiuc nghidm. Nhi xudt ban Khoa hgc Ky thuat.
3. Arum Mujumdar, Marcel Decker Publications. Handbook of Drying Technologies.
4. Perry. Chemical Engineering Handbook.
5. K. Rastikian, R. Capart and J. Benchimol.
Modelling pf suger drying in countercurrent cascading rotary dryer from stationary protiles of temperature and moisture.
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 2/2012 59
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RESEARCH ON SUGAR DRYING TECHNOLOGY ON DRYER DRUM
Nguen Tan Thanh, Ton That Minh Summary
Drying sugar plays an important role in sugar producUon, research sugar drying technology on dryer drum (appropriate equipment di-ycr in small and medium iiroducUon) purpose of finding an appropriate drying regime for a high quality product, less energy consumption and the shortest drying time. The main parametei-s affecting the diying process and llic^ impact of their use in research is: temperature drying agent t", (°C) (70°- 80°-90°); speed diying agent V (m/s) (1-2-3) and speed of rotation of dmm n (rpm) (2-4-6).
By the experimental method to find opUmal, has built quadratic regression mathematical equations Y = 16.73- 0.19X1-0.21X3- 0.37X,^- 0.34X0^- 0.21X:,' detennined the optimal parameters of the process is t", = 77.5°C; V = 1.7 m/s; n = 4 rpm. product quality and high economic efficiency with drying time is T = 16.78 minutes. On the other, this topic has designed and built a complete dnim dryer capable of deploying to production. Equiment suitable for sugar producUon base of small and medium scale and can drying many different types of products as tea. coffee, tobacco, food grains and other pharmaceutical products, etc...
Keywords: Sugar drying, rotary drum drier, small scale.
Ngudi phan bi^n: GS.TSKH. Ph^un Vin Lang
