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NLN''''108 11/2012 15 NGHIEN CUIU THl/C NGHIEM SIT DUNG LCTP MUOI KHO LAM LCrP DEM TRO SOI TRGNG SAY MUOI TINH LOTP SOI LIEN TUC Experimental research for using the supported dried refined salts particle[.]
NLN'108-11/2012-15 NGHIEN CUIU THl/C NGHIEM SIT DUNG LCTP MUOI KHO LAM LCrP DEM TRO SOI TRGNG SAY MUOI TINH LOTP SOI LIEN TUC Experimental research for using the supported dried refined salts particles layer in the continuous fluidized refined salt drying TS BUI TRUNG T H A N H , Khoa Cong nghe Nhiet lanh.DH I OAT VAN O ^ Muoi tinh sau che bien neu khdng s l y Ihi ehi sau mdt thdi gian ngdn lyu kho se bi vdn cue tang, khoi idm giam cam quan, giam chdt lyong Irong s d dyng, khdng cdn kha ndng phoi trpn vdi cdc loai nguyen lieu khde trfin edc day ehuyfin t y ddng cdc cong nghfi che bten thye pham va san x u l t hoa chlt[6] Nhy vdy v i n de ddt eho tat ea edc nhd may san xuat muoi tinh Id cdn phai thye hifin tiep cdng doan say mudi linh trydc kht ddng bao x u l t bdn Phan tich c d hgt,dd I m nguyfin lifiu, ddc tinh rdi cua hat sau cdng dogn ly tdm, p h i n ldn ngydi ta dfiu nghT ring ed the say khoi hat ndy b i n g mdy s l y t i n g sdi Tuy nhifin thyc nghifim s l y d c h l dd s l y t i n g sdi cho thiy edc hat n i m k l se k i t dinh nhanh chdng, hinh thdnh tdng khoi hgt d i n din vific tao tdng khoang trfin ghi phdn phoi khi, Idm cho ddng ndng ty khoang chda bfin dydi buong say ehi thoi qua cde viing tren ghi phdn phoi md khdng can di qua khoi hat trfin ghi dang k i t dinh Thl nghiem ttiyc hifin d p lac nhdn thoi Id dydi Ifin cd nhifit dd tang dan ty 30 °C Ifin den 170°C vdi chieu ddy khoi hat 100mm, cho k i t qua dd chat cua khoi hgt se tdng dan td trang thdi rdi t y nhien 0,0 kg/cm^ Ifin d i n 0,66 kg/em^, Sy lien k i t khoi phdn bo tdng d i n d i n td Idp hgt ddy ghi phan phdi Ifin Idp hgt trfin b l mdt[6] Vdi k i t qua trfin cho thay khdng the s l y hat muoi tinh bing phyong phdp s l y Idp sdi thdng thydng n l u khdng cd dyp'c giai phdp ngdn ehan lien k i t dinh hat vdi hat, hat vdi ghi phdn phdi vd hat vdi Ihanh vdch buong say Bdng nhieu nghifin cdu thyc nghiem lac gia da dya giai phdp chong ket dinh khdi mudi tinh am qud trinh say b i n g each s d dung mdt lypng muoi tinh khd hpp 1^ bo tr( s i n trfin ghi phan phoi n^ay Id qud trinh gia nhifit da eho phep phd v d hfin ket hgt vdi hat, hgt vdi ghi phan phoi vd hat vdi vdch buong s l y vd dd s l y d y d c khoi hat muoi tinh I m bdng mdy say Idp sdi lifin tyc eho c h i t lyong san phim vypt trdi so vdi cdc logi mdy say hign dang s d dgng cdc nhd mdy c h l b i l n muoi tinh Trong khudn kho bdi bdo, tdc gia trinh bdy cdch xde djnh mien gid tri eua ehilu ddy Idp hat muoi tinh khd ldm Idp hat tra sdi s l y muoi lmh Idp sdi hay ndi mdt cdch khde Id xdc djnh ty Ifi m u l l khd ban d i u trp' sdi say muoi tmh I m , Cong nghiep TP Ho Chi Minh II.HOAT DONG S A Y M U I TINH TREN MO HINH T H y C NGHIEM Md hinh s l y mudi tinh Idp sdi d y o e bo tri nhy hinh 1[6] Buong s l y cd hai khoang, khoang thd nhat dung de nhan vdt lifiu vd s l y khd san pham d i n dd am bao quan, khoang thd hai Id khoang ldm ngudi san pham say den nhifit dp bao quan, phdn cdch gida hai khoang la tdm chdn Chieu cao tam c'^'^'i dyp'c Ihifit k l ed the d i l u ehinh len, xuong dyac Hinh Mo hinh thuc nghi$m say muoi bnh lip soi 1-Vit til nap nguyin lieu; 2-bd cip Iiiu vao may siy, 3-khoang siy; 4-dng thoit im; S-cda quan sit vi l^m ve sinh; 6- cda sin phim siy; 7-cyclone thu hdi bui mudi; 8- cyclone nu'dc xiy ly thai Khi b i t dau say, ta bo tri mpt ldp muoi tinh khd cd dp I m khoang 0,2% trfin ghi phdn p h l i d khoang thy n h i t va t i l n hdnh gia nhifit tdc nhdn say den nhifit dp s l y cua edng nghfi Muoi tinh d y d c vit lai (1) e i p vdo bd ddnh toi (2), bd danh toi cd nhifim vu rai dfiu khdi hgt vao p h i n dau cua khoang say thd nhdt H a t m u o i tmh y d t qud trinh roi xuong khoang s l y d y a c h i p thu nhifit td ddng tde nhdn thoi td d y d i Ifin Xen lan ddng tdc nhdn ndng thoi td d y d i Ifin Id vd so cdc hat muoi tinh khd, ndng triim Ifin, cdc hat mu6i tinh y d l , da Idm phdn rd, tdch kh6i hat am thdnh cdc hgt rdi rac Tgi buong say difin qud trinh trao doi nhifit vd Irao d l i am mdnh liet d y d i cdc pha doi iyu -hgt, hat ndng khd -hgt y d t am vd truyin nhifit ddn nhiet giya vdeh bao quanh buong say - den khoi hat muoi tmh l m [ ] Vdi cdch cap muoi tinh nguyen li$u vdo khoang s l y theo hydng td trfin x u i n g dydi dang Idp hgt mdng cung vdi ddng tdc nhdn ndng cd dp s u i t thoi td dydi Ifin, k i t hp-p vdi s y h6 trp' eua Idp mu6i khd sdi 16'NLN-108 Ml/2012 dfiu tren ghi buong say da Idm cho khoi mudi linh y d t vda dyp'c cap vdo buong say dd Ihoal am nhanh chdng roi hda sdi (fluidization) chimg vda roi xudng d phan dau khoang sdy Nhd cdch bo tri vd each dieu ehinh kich thydc cdc cda cap tdc nhdn s l y hp'p ly da Idm khoi mudi linh am trfin ghi vda sdi vda thodt am vd vda dich chinh dan v l cuoi khoang s l y de dat dp am pham vi 0,2-0,25% Mudi tinh khd sau cdng doan sdy tiep tue "nhay qua" tdm phan cdch khoang say d l vdo khoang Idm mat d y a e bo tri ke t i l p va djch c h u y i n dan ngoai de dat nhifit dd hat < 70 °C tai cda eua buong sdy[6] III NGHIEN Cl>U Sl> DUNG LOT HAT T R O SOI TRONG S A Y VAT LIEU CO THUOC T I N H K ^ T DiNH Sd dyng edc hat tro (inert particles) dk hd tro qua trinh "gia Idng" nhifin lifiu biomass cd dp am cao, nhiet tri thdp dyoe b i l t dfin cdng nghe Id ddt Idp sdi[2] Theo Howard (1989)[2], cdc hat Idm Idp tro sdi phai cd mdi so dde linh ca ban ehung bao gom'dang tron, khd cao, nhifit dung ridng Idn, ngodi cdn cd dde d i l m rieng - Cd kha nang b i n vyng - Chju dyp'c nhigl dp theo yfiu c l u cdng nghfi, - Chju dyae va ddp mdi tofdng nhifit dd cao - Chiu dyp'c mdi mdn, - Kich thydc trung binh cua cdc hat tro phai thich hp'p theo cde dieu kign dng dyng, nhifin n l u ede hat tra Idm Idp dfim md bfi thi hfi sd trao doi nhiet t d ldp hgt d i n be mdt Iruyfin nhigt se cao vd difin tieh b l m§t trao doi nhigl yfiu cau d l lay nhifit tai mgt ty le da d y g c cho se it nhat Kich t h y d c hgt tra sdi bd thi van loc ldi hgn cua ehiing hoat ddng sdi ddng cung bfi, vay nhilu trydng hop ehimg se khdng tyang xdng vdi vdn toe sdi eua vdt lifiu say, k i t qua Id cac hgt tro sdi se bj phdn tdn theo thai ngoai gdy hao ton Idp hat tro sdi ddn dfin ldm cho qud trinh s l y hat bang Idp sdi khdng on dinh, Ngodi cdc hgt tro Irp' sdi phai re tiln, dfi k i l m IV ThiPC nghiem do-n y l u t6 xac dmh chilu day Idp hat tro" soi say mudi tinh Theo quan diem cua Howard (1989)[2] ve loai hat tra trp- s6i, tdc gia bdi bdo chpn khoi hat muoi khd logi kich thydc da phdn tan, dp am M< 0,2 % Idm Idp hat tro sdi[6] N h i m de xde dinh d y p c mien gid gid trj ve ehilu ddy ldp hat trp' sdi Ho (dyoe md hod X i ) tde gia t i l n hdnh thyc nghifim dan y l u to [4,5,6] bdng cdch cho b i l n thifin chieu ddy Idp hat trp' sdi d I O m d c 0,25mm ;0,35mm;0,45mm;0,55mm,0,65mm,0,75mm;0,85mm ,0,95mm; 1,05mm, 1,15mm,trong van gid nguyen cdc thdng so vdn toe Idc nhdn s l y Vg = 1,3m/s (dydc ma hod X2) nhifit dp tde nhdn s l y tg= 160 ° C ( d y o e md hod X3)vd kich t h y d c hat sdy dp= 1,05mm {dyae ma hod X4) ed anh h y d n g d i n edc hdm mye lifiu vfi dd I m (Yi), chi phi lieu hao nhifit lyp'ng rifing (Y2); hifiu s u i t thu hoi san p h i m (Y3)va chi phi lifiu hao difin ndng rifing(Y4) Cae thdng sd eo dmh lam thyc nghifim dan yeu td bao gom - Dd am mudi tinh nguyen lifiu cap vao Mi = 4,7%, nang s u i t Gi= 24kg/30 phut (thyc nghidm liy 30 phiit nap lifin tuc vdy tong khoi lyp'ng muoi thdnh pham ly t h u y l t (G2) dat ehuan dd am * M2 = 0,2% ed gid tn G2 = Gi - W = 24kg -0,88 =23kg Trong dd: G2 = G 2,+ G 2 + G 2,3 G 21 -lyp'ng thdnh pham, G 2 - l y a n g bui thu h6i dyp'c, G 2.3- l y o n g bui muoi ndm ldn thai phai x y ly Gid In thdnh pham G21 d y o e tinh theo % (hifiu suat thu hdi) A = (G 2i/G2) 100% 4.1 Anh hwang cOa chieu day Idp dim trp' sol (Ha) din dp am san pham say (Yi) Theo so lifiu thyc nghifim thu dyp'c trinh bdy theo bang 1[6],xy ly sd lifiu thong kfi xae dinh dyp'c hfi so tyang quan giO'a (Xi vd Yi) ed R = 0,956, hfis6R^ = 0.913, hfi sd ddnh gid mdc y nghTa eua hfi so hoi quy (Xi,Yi.i) Id 0,026 Ta lap dyp'c phyang trinh hdi quy tong qudt' Y i = A i X , ^ + B i X , + Cl (1) K i t qua x y ly sd li$u vdi m d c y nghTa eua he so hoi quy A,, B i ; Ci bang Anova lln jyot: 0,036; 0,027; 0,33cho phep ta tap phyang trinh hoi quy [5],[6] Yi = 0,199 H^o -25,075 Ho + 873,219 (2) Ta xay dyng dyp'c thj l y o n g quan gida (Xi,Yi) vd cd eac nhdn xdt - C h i l u day Idp tro sdi Ho= 25mm - 35mm khdng cho phep "gia Idng" khoi hat muoi linh am dya vdo m^ay say theo tinh loan ve nang s u i t Khdi hat I m bi k i t khoi cdng lai khu v y e nap lifiu vd phin d i u cua budng s l y - Chilu d a y j d p hat Ho= 45mm tyong dng vdi ly Ifi khoi lyong mudi tinh am ngp vdo mdy say so vdi khli lyp'ng mudi khd x i p xi b i n g 50%, bao dam khoi hgt sly "gia Idng" de ddng, san pham dat dd am M2= 0,27%[6] - Ldp hgt trp' sdi Ho = 55mm vd Ho = 65mm cho khdi hat say sdi deu vd on dmh nhat, tyong dng vdi ty Ie hat y d t vd hat khd pham vi 34% -^ % eho chit lyp'ng s l y dat dgt ehuan ve dO am [6] - Ldp d#m Ho = 85mm, qua trinh gia long trd nfin khd khan han, c h i t l y o n g Idp sdi giam, dd am ndm d mdc gidi hgn trfin M2= 0,28% NLN* 108-11/2012*17 - Chieu ddy ldp d$m Ho> 95mm, chat lyong Idp hat gia Idng kem hdn, dd am khdng dat yfiu eau (M2 = 0,6%) Khi ldp dfim Ho =105mm -115mm, hoat ddng say bing Idp sdi e h i m dirt, muoi nguyfin lifiu bi ddng cue dya vdo buong say Chieu ddy Idp dfim Ho= 45mm - Ho= 85mm, lieu hao nhifit lyp'ng rifing biln thifin pham vi 1040 -^ 1050kcalfl(g am bay hai - Chieu ddy Idp hgt HQ > 95mm Idm tdng lifiu hao q= 1120,3 kcal/kg nydc, nhyng chdl lyong s l y Igi khdng dat yfiu eau - C h i l u ddy ldp hat Ho = 65mm cd tifiu hao nhiet lypng neng thap nhit, q= 1025kcal/kg nydc, san pham s l y dat am theo chuan M2= 0,2% 4.3 Anh hwang cOa chieu day Idp dem (H(^ den hieu suit thu hoi san pham (Ys) Theo tinh todn ly thuylt tong Ihu hdi chuan G2 = 22,964kg Ket qua x d ly so lifiu thi nghiem xac dinh he sd tyang quan gida (Xi)va (Y3) Hinh D6 thj tuong quan chiiu day Idp dem tro soi va ty le am san pham so vai am chuan Chi eh! t!^_u hao nhiet Iircmg neng kcal/kp am bay / / \, \ ^ ~~^X Y3=A3Xi' + B3Xi+C3 hg (5) K i t qua x d ly sd lieu b i l n thyc vdi mdc y nghTa cua he so hdi quy A3, B3, C3 bang Anova ldn lyot 0,020, 0,018 vd 0,00 cho phfip xay dyng d y p c phyong trinh hoi quy ,/ Y3 = 0,415 H^o -0,03 Ho + 75,164 (6) Vd thilt lap d y o e thj quan hfi (Xi , Y3) vd cd cdc nhdn xfil, / /^ - Chieu ddy ldp dfim Ho = 55 - 75mm, khdng anh hydng nhieu den hifiu s u i t Ihu hoi san pham say Hifiu s u i t thu hoi dat td , % - 89,4% Hinh Do thi tuang quan chiiu d^y lap d$m tro soi va tieu hao nhi$t luang rieng 4.2 Anh hwang cua chieu diy Idp dim tra soi (H^den tieu hao nhiet Iwp-ng rieng K i t qua x d ly so lifiu thong kfi xdc djnh he so lyong quan gida (Xi) vd (Y2) cd R= 0,969, hfi so R^ = 0,938, mdc y nghTa cua hfi so t y a n g quan (Xi, Y2) Id 0,015 cho t h i y md hinh vd quan he (Xi vd Y3.1) ed m i l quan hfi rat cao, ta Idp d y o e phyang trinh hoi quy long quat cd dgng' Y2=A2Xi^ +B2X1+ C2 cd R = 0,94, hfi s6 R^ = 0,886, mdc