KHOA HOC - CONG N G H E NGHIEN CUU MOT SO THONG SO CUA THIET Bj SAY TANG SOI DE SAY HANH LA ChuVdnThiifn' TOMTAT Bdi bdo gidi thiiu ket qua nghien cim cong ngh^, thiet ke vd che tao thiet bi say tdng soi de say hdnh ia Thi nghidm say da duac tien hdnh a che dp nhiet: 50: 60: 70 vd 8u'C vdi che dp ldc dp lac nhdn: 1,0; 1.3; 1,6 vd 2,0 m/s va a cap be day nguyen tiC'u: vd 10 cm, tir dd tim tdc dp tdc nhdn say Id 1.6 m/s nhiet dp thich hap la 7(1'C Mpt mdy say tang sdi da dirac tinh todn thiet ki' vd che [go gdm cdc bpphpn: Id dot than dd vdi bp trao ddi nhiet bp phdn phoi khi, bp phgn cdp lieu vd ihdo sdn phdm, bp phgn hdi Im thdi, san say vdi ca cdu rung de ho tr(X sdi han ddu nguyen lieu cdn qud dm, ldm gidm tdc dp tac nhdn 1,3 m/s Qua ihu nghiem say hanh Id tren mdy thiet ke dd xdy dimg dugrc quy h-inh say hdnh Id: nhiet dp 7(f'C, tdc dp tdc nhdn 1,3 m/s tdn so rung 275 l/ph, be ddy 100 mm, hdi hru 60% thai sau say 10 phut vd thai gian say long 25 phut se cho chdt hrgm^ sdn phdm cao So sdnh cho thay dii chi phi spy cao han mpt sd phirang phdp say hien diing khdc nhung chdt luxmg ddm bao ve mdu sdc dep, xanh t(r nhien, tham dgc tnmg vd thdi gian say ngdn Tir khoa: Say, loc dp sdi tdi thieu .say tdng soi, say, rung RESEARCH ON FLUIDISED BED TECHNOLOGY AND EQUIPMENT FOR DRYING OF SPRING ONION LEAF Ciiu Van Thi^n' SUMMARY This paper siiows tiie research resuits of technoiogy, design and manufacture of a fluidized bed dryer for spring onion leaf drying Experiments were carried out at temperatures of 50; 60; 70 and 80"C with drying air velocities of 1.0; 1.3; 1.6 and 2.0 meters per second, and used levels of material thickness of 5; and 10 cm It is found that drying air velocity of 1.6 meter per second and drying air temperature 7(fC are suitable for drying of spring onion leaf on fluidization drying equipment A fluidized bed dryer was designed and manufactured that includes components of coal furnace with heat exchanger, drying air distribution, material feeding and product unloading, discharged air recycle, drying floor with vibration component supporting initial fluidization when material is still too moist, helping to reduce drying air velocity to 1.3 meter per second Drying of spring onion leaf with the designed dryer was conducted A drying process was reconimended for drying of spring onion leaf using a fluidized bed dryer is as following: drying temperature of 70 C, drying air velocity of 1.3 m/s, vibration frequency of 275 l/min, material thicliness of 100 mm, recycling of 60% of discharged air after initial 10 mins, and total drying time of 25 mins In comparision lo some other existing drying methods, nuidization drying gives higher drying cost, but higher product quality, such as having natural colour, specific odour, and lower drying time Keywords: Drying, minimum fluidization velocity, fluidized bed diyer, drying air, vibration DAT VAN DE Cong nghe t k g soi tir lau da duac ung dung de say cac nguyen lieu rai o cac nuac phat triSn Uu dtem: co the say nhiet cao, thoi gian ngan, san phant co kho dong ikn (do dugc dao trpn va tiep xuc toan bg be mat voi khong kh, say o trang thai gia soi), hieu suit trao doi nhiet va am giaa nguyen lieu 'IS Vien Co dien nang nghiep va Cong nghe STH ^^ ot) va tac nhan sAy cao, rut ngan thoi gian sdy, chit lirgng san pham cao Hon cac phuong phap khac; ,hist bj nho gon, nang suit cao Tuy nhien, a „ufc ta viec ung dung cong nghe sjy tjng soi hign chua nhiSu va hoan toan phu thuoc vao ftiSt bi cua nuoc ngoai Hien nay, nganh chJ y e n thuc phdm dang doi hoi' cac san phSm ck ^"^'^ "^"8 '^^° '^hat lugng, dac biet d6i vcri TAP CHf CONG NGHIEP NONG T H O N - S O 12-2014 K H O A H O C - CONG N G H E nhang san pham xuat khau Cong nghe va thiet bi sdy tang soi se dap diing dugc yeu cau De mo rong pham vi ung dung ciia cong nghe va thi^t bi, chu dong nam giu: cong nghe nuac, can nghien cuu cong nghe va thiet bi say tang soi de say hanh la II TONG QUAN Sii dung coi^ nghe tang soi ITnh vuc say da dugc thuc hien tu lau tren the gioi Say tang soi phu hgp cho cac loai nguyen lieu dang bgt, hat, vien vai ca hat trung binh tir 20 ^m - mm [3] Tai Thai Lan, Soponroimarit va cong su [8] da nghien ciiu che say tang soi vcri tuong CO i m tij 31-49% dai nhiet tir 110-140°C, t6c tac nhan siy tir 2,4- 4,1 m/s (t6c toi thieu cho tuang la 1,9 m/s) vai bk day lap hat tu 10 - 15 cm Ket qua chi rang: luong say theo cong nghe tang soi chi nen siy xu6ng am 23,5% de tranh mit vo Cac diiu kien toi uu de giii chat lugng va giam chi phi la say nhiet dp 140"C vai be day 18 cm, t6c tac nhan 2,9 m/s va hoi luu 90% thai se cho ty le nut 27%, va 1,7% va chi phi nang lugng rieng 6,8 MJ/kg nuoc b6c hai Nam 1994, Soponronnarit [7] da nghien cuu va thiit k& may say tang soi lien tuc, co nang suat 200 kg/h d l siy lua tir dp i m ban diu 30% xuong 24% vai nhiet siy la 115- 120°C Tac gia chi rang dp am cuoi cua lua khong nen thap hem 23% niu cin tri tring va ty le gao nguyen cao Nhiet say cung nen dugc giai han IS^C vai t6c tac nhan la 2.3 m/s, be day lap hat 10 cm (lop tmh) va hoi luu 80% thai Tir kit qua nay, Soponroimarit va Prachayawarakom [9] da thiet ke may say liia tang soi vai nang suit 5, 10, 20 tan/h dimg diese! hoac diu can lam nhien lieu dot tao nhiet va h6i luu 66% De tang ty le gao nguyen, Soponronnarit va cpng sir da nghien ciiu say ting soi ba giai doan va cho thay say a 150 C phut, giam am tir 33 xuong 16.5%, sau u 30 phut r6i thong gio bang trai 20 TAP CHi CONG NGHIEP NONG THON - SO 12 phiit a 30"C 0.15 m/s se cho chat lugng gao chap nhan dugc Nam 1987, Trung tam nghien ciiu va phat triin chi biin liia gao cua Srilanka da nghien Cliu che tao may say tang soi theo me, dung 16 dit triu de say liia May co san dot 16, quat tac nhan siy 15 kW, luu lugng 30.000 m-'/h du lam s6i 630 kg liia a dp i m 32% vai lap hat tmh 200 mm Kit qua cho thiy mot me sa\ het 65 phiit, tieu thu nang lugng thap so vai say tren may siy dong lien tuc thong thuang (thoi gian say gio say + gio u) [1] Tuy nhien, co nguyen lieu cr dang dinh ban diu qua im rit kho d i tao s6i cho nguyen lieu De giai quyet van de, co the diing bg phan khuay co hpc nhung d6i hoi phai say ngat quang va lam phiic tap may say Mot each khac cung dugc dimg la sir dung co cau lech tam de lam rung may say Huang rung co the thay doi dugc nho dao chieu quay cua dgng ca, bien dp rung dugc thay d6i lech tam de dam bao dat su phan phoi tac nhan say dong deu tren san say Cong ty Oliver da nghien ciiu va cho thay lgi thi cita say tang soi dang rung la tao huong chuyen dpng cua nguyen lieu, su soi c6 the xay ca a toe dp tac nhan say thap, va thai gian luu ciia nguyen lieu co the dieu chinh dugc Theo Pakowski say tang soi dang rung diing de say ca nhiing nguyen lieu kho s6i ca hat 1cm Tan so rung thuang nam khoang - 25 Hz vai bien vai mm [6] Nhieu cong ty nhu Barr-Rosin ciia Anh hay Carrier va Ventilex ciia My cung da nghien ciiu va phat trien nhieu loai may say tang soi dang me va hen tuc a ca dang tmh va dang rung de ling dung vao nhieu Itnh vuc nhu say duang, muoi cat hat nong san, hot mat siia, rau Dang rung co the dugc lam dang rung thang diing hoac lac theo huang di chuyen ciia nguyen lieu say Tan so rung c6 the thay d i i dugc tren dai rpng, vai bien dp dieu chinh va co dinh cho KHOA HOC " CONG NGHE Diic, Ha Lan, vai cac dang thiet bi khac Cong ty thuc pham dinh duang Nam Ha (Nam Djnh) da nhap mot day chuyen che biin thiic an dinh duong ciia Diic gom thiet hi siy ting soi dang lien tuc, su dung ngu6n nhiet tir noi hoi qua bp trao doi nhiet timg loai nguyen lieu, Nha co rung ma Iugng cin thiit giam dang ki, din din tieu hao nang lugng cho quat gio va cho nhiet Iugng giam Kudra va Efremov da nghien ciiu dpng hpc say cac nguyen lieu dang hat theo nguyen ly tang soi Nghien ciru da dugc tien hanh tren san say rung ngat quang vai rau can tay thai ngan, va tren san siy tinh co bg phan khuay dao co hpc voi ca rot thai xiic xic a dai nhiet tir 50 - SO^C Ket qua cho thiy tic dp giam am lan hon nhieu so voi nguyen ly siy doi luu thong thuang [4] Theo Liukov, tra luc ciia san say len dong tac nhan say nSn dai tir 100 - 200 mm H2O tiiy thupc vao nguyen lieu va b i day lap nguyen lieu dugc say Be day lap nguyen lieu say (tmh) c6 thi dugc diiu chinh nha van tran, thuong tir 50 - 300 mm [5] Cac cong ty hoa dugc ihuang trang bi cac may say theo me dang thap tru vai nguon nhiet tir dien tro Viec nghien cuu c6ng nghe va thiit bi say tang s6i ciing mai chi bat dau tir Vien Co hgc ling dung voi muc dich chii yeu de phuc vu nganh hoa dugc May say dugc Vien nghien ciiu va che tao thuang la may say theo me co nang suat tir 20 - 200 kg/me, va nguon nhiet chinh la nang lugng dien (tir - 5 kW chua ke cong suat ciia cac dpng co) nen chi phi say rat cao Phan Hieu Hien (Truong Dai hpc Nong lam TP Ho Chi Minh) da nghien ciiu cong nghe va thiet bi say tang soi de say liia, ngo hat Nghien cim va thiet ke dua tren ca so va tiep noi cac nghien ciiu ciia Soponronnarit (Thai Lan) Ket qua nghien ciiu vai thiet bi say nang suat tan/h da dugc img dung tai C6ng ty Luong thuc Long An Tuy nhien, chat lugng gao chua cao, ty le gao nguyen thap lua dugc say voi nhiet qua cao (11 S^C) va che dp s6i ciia bat may chua deu nen dp am san pham khong dong deu Vi vay, tac gia da khuyen cao sir dung may say tang soi cong nghe say hai giai doan de giam nhanh dp am ciia liia thu hoach co am cao a giai doan dau de kip thai tam trfl, sau diing may siy thong thuang de say lai a giai doan sau II NOI DUNG VA PHUONG PHAP NGHIEN CUH 2.1 Vat lieu - Hanh hoa nia sach, cit bo gic cii va ngpn loai bo cac la lia heo, thai ngan tir - mm - May siy ting soi thi nghiem "Universal Rapid Dryer TG-1" (hinh la), vai dai nhiet dieu khien vo cip tir 40 - UO^C, luu lugng gio tu 54 - 108 m^/h ung vai t i c gi6 tren san say tit 0,581 - 1,056 m/s Buing siy co thi tich lit CHi CONG NGHIEP NONG THON - SO 12 - 2014 Mpt nghien ciiu ve anh huong cua toe dp tac nhan say say tang soi dugc tien hanh a 6Qf*C de say thuoc vien theo me a che dp toe dp tac nhan say khac Voi luu lugng tac nhan 6000 - 7000 m^/h cho thai gian siy la 19 phiit de dp am tir 63% xuong I - 3% Con che dp say vol luu lugng tac nhan giam dan (10 phut diu a 5900 m^/h, 10 phut sau a 5100 m^/h, 10 phiit ke tiep 3800 m^/h va 16 phiit cuoi la 3000 m /h) thi thai gian say tang len den 46 phiit Nghien ciiu cho thay toe dp tac nhan phai dii lan de nang h^t nguyen lieu len khoi san say, nhung nen thap han toe dp dich chuyin cua hat O che dp dau tien, nang lugng tao toe gio cao khong dugc diing hoan toan cho trao dii nhiet C) che dp say sau mac dii thoi gian siy dai han nhung toe dp tac nhan vira dii de lam soi hat \ a cho phep du thai gian de khuich tan im tir ngoai be mat hat, vi vay chit lupng (dac tinh hoa ly) ciia san pham khong hi thay dii [2] d nuac ta, cong nghe va thiet bj siy ting soi da dupe img dung a mot so noi cac nganh thuc pham va hoa dugc Hau het cac cong nghe va thiet bi deu dugc nhap tir nuoc ngoai nhu KHOA HOC - CONG NGHE bang thep khong gi Mot budng siy phu dugc lam de c6 the siy vai tic dp gio tii 1,5 - 2,6 m/s Thiet bi can phan tich va dp am nhanh Adam AMB-310 ( hinh lb) Thiet bi luu lugng va toe dp gio Airflow TA - 35, dai - 20 m/s, dp chinh xac 0,03 m/s de xac dinh toe dp gio va lugng tac nhan hoi luu a) b) Htnh Thiet bi diing thi nghidm a) May say lung soi rlii nglupn 'Hmversal Itei/uJ Dryer 7G-I " h) IhiOl bl do am Adam AMB-310 2.2 Noi dung nghien cihi Tim hieu thuc tien tinh hinh iing dung cong nghe va thiet bj say tang s6i va ngoai nuoc - Nghien ciiu anh huong ciia che say hanh la theo cong nghe tang soi: toe dp va nhiet tac nhdn say, be day nguyen lieu din thoi gian say va chat lugng mau miii - Thiet ke, che tao va thu nghiem thiit bi say tang soi de say hanh la - Xac dinh anh huong ciia tan so rung, ty le hoi Iuu thai den chi phi nang Iugng rieng say, thai gian say va chat Iugng san pham - So bp so sanh hieu qua say vai viec say bang may say truyen th6ng hien 2.3 PhiroYig phap nghien cuu - Thu thap thong tin qua cac ngu6n tai lieu khac nhau: sach, bai bao, mang internet - Sir dung phuang phap thuc nghiem dan yeu to tren may say tang s6i ph6ng thi nghiem va may say thiet ke - Sii dung cac thiet bi ph6ng thi nghiem de xac dinh dg am - Sii dung phuong phap danh gia cam quan - Sir dung phuang phap thong ke toan hgc xir ly so lieu Thi nghiem dugc tien hanh a che dp nhiet: 50: 60; 70 va 80V vai chi dp tic dp gio: 1,0; 1.3; 1.6 va 2,0 m/s va cap be day nguyen lieu: 5, va 10 cm HI KET QUA VA THAO LUAN 3.1 Anh huong cua toe dp gio va nhiet dp tac nhan say den chat lirpng Ket qua say hanh la a cac che dp be day, nhiet dp va toe dp tac nhan say khac cho thiy a cip be day thi tic dp gio 1,6 m/s la tic dp ma hanh soi tir dau C6n tic dp 1,3 m/s hanh se soi sau vai phiit ke tir bit dau Tuy nhien neu thiet ke may say tang soi ket hgp vai rung thi co the lay tic dp tii thiiu la 1,3 m/s Cac che dp say vai toe dp nho (1 m's) deu cho mau hanli hoi tham nguyen lieu kh6ng dugc soi tir dau, lam cho nguyen lieu hi ii nhiet c6n am Khi say a nhi?t dp SO^C, tic dp gio 1,6 - 2,0 m/s va vai cac be day khac deu lam hanh kem xanh Kit qua thi nghiem the hien a bang I 3.2 Anh hvong ciia toe dp gio va nhiet dp tac nhan say den thoi gian say Ket qua thi nghiem the hien tren hinh 2,3.4 Hinh Anh hirdng ciia nhiet dp vd tdc dp tdc nhdn say den thdi gian say d be dcry cm Hinh Anh Inrang cua nhiji vd i,Jc dp idc nha sdy din thai gian say a be ddy cm TAP CHi CONG NGHIEP NONG THON • SO 12 - 2014 KHOA HOC - CONG N G H E Hinh Anh hirdng ciia nhiet dp vii tdc dp tdc nhdn sdy den thai gian sdy a he dciy 10 cm Nhan xet: - Noi chung nhiet dp tang thi thoi gian say giam cho ca cip be day nguyen lieu Tuy nhien, tang tit nhiet 70 len SO^C thi thai gian say giam khong dang ke - Tic dp tac nhan say tang cung riit ngan thai gian say mot each dang ke, dac biet tang tir 1,0 len 1,6 m/s Su chenh lech thai gian say giQa che dp 1,6 va 2,0 m/s khong ro rang hau het nguyen lieu deu dugc soi, dao trpn va nguyen lieu dugc tiep xuc voi nhiet tren toan bp be mat ciia no - Voi be day khac thai gian say khac nhieu chi a dieu kien nhiet dp tac nhan say thip (50 va 60"C) va toe dp tac nhan thap m/s, vi nhiet dp thap nen su trao doi am kem v^ nguyen lieu dugc s6i a be day nho cm nhung khong dugc s6i a be day 10 cm Khi toe dp tang len 1,6 - 2,0 m/s du lam soi ca be day hoac 10 cm va nhiet dp say tir 70 - 80 C thi thoi gian say khong khac nhieu Tir ket qua thi nghiem tren, vai hanh la co thi xac dinh dugc toe tac nhan toi thieu cho hanh la la 1.6 m/s vai am ban dau la 93%, day tTnh lop nguyen lieu 10 cm la hpp Iy Thoi gian say 25 phiit a nhiet dp 70"C Tuy nhien, neu thiet ke may say co sir dung co cau rung ho trg, tac nhan say chi can co toe dp 1,3 m/s, vi sir chenh lech thai gian say gi&a 1.3 m/s va 1,6 m/s la khong nhieu (15%) Che dp cong nghe say hanh la sau thi nghiem ph6ng nhu sau: Nhiet dp tac nhan say: 70"C; toe dp tac nhan say: 1,6 m/s (neu co rung: 1,3 m/s); be day lap nguyen lieu: 10 cm; thoi gian say: 25 phiit Bdng Anh hirdng ciia cdc thong so den chdt hrang man vd miii Be day, (cm) Toe dQ gio, (m/s) 1.0 50 Chat lirgng man mui Xanh den lliom Nhiet say ("C) 60 70 Chat lupng mau, Chat livgng mill mau, mill Xanh tham tham Xanh, tham Xanh tham, tliam Xanh, tliam Xanh, tham Xanli den, thom yeu Xanh tham ihom Xanh, tham Xanh, thom Xanh, tliam Xanh iham, tham yeu Xanh tham, tham Xanh, Ihom Xanh thom Xanh, tliom Xanh tham, tham yeu Xanh, tham Xanh, iham Xanh, ihom Xanli tham, Iham yeu Xanh tham, thom Xanh, thom Xanh, thom Xanh thom yeu 1.3 Xanh, tham Xanh tham Xanh den, Iham yeu Xanh den thorn Xanh thom Kem xanh, tham Kem xanh, thom Xanh tham tham yeu Xanh, thom yeu Kem \anh, thom Kem xanh, thom Xanh tham Xanh, iham Xanh tham, thoni 1,6 2.0 Xanh tham Xanh, tham Xanh Ihom Xanh, iham Xanh thom Xanh, thoin Kem xanh thom Kem \anii, thom 80 Clial lugng mau, miii Xanh, thom 1.3 1,6 2.0 1,0 1.3 1.6 2,0 1.0 10 Ghi ehti (trgng thai ban dau) Khong soi 5' diu Sol yeu Soi Soi Khong soi 10" dau Khong soi 3" dSu Soi Soi Khong sol 18" Am Khong SOI 6' dau Soi nfiav Soi T A P C H l C O N G N G H I E P N O N G T H O N - SO 12 • 2014 K H O A H O C - CONG NGHE 3.3 Tinh toan thiet ke may say Dieu kien thiit ke: Dp im hanh la: 93%; ^ (voi hanh la thai n ^ - mm): 175 kg/m^; nang suit may: 25 kg/h; nhiet dp say: 70''C; nhiet dp moi truong: 25°C; bi day lop nguyen lieu tinh: 100 mm L=2,0 X 0,6 X 0,6 x 3600 = 2592 m % (= 2900 kgli) Tir lugng tac nhan say, xac dinh dugc lugng nhiet can de tac nhan dat nhiet say can thiel: Q ^ 116640 kJ/h (dam bao lugng nhiet cin thiet de mang bay hai Iugng am da xac djnh a tren) Buong sdy: Voi nang suit yeu ciu 25 kg/h, va thai gian siy theo cong nghe la 25 phiit, tinh dugc khii lugng siy 25 phut la 10,42 kg Nhu vay, the tich nguyen lieu buong siy: 10,42 / 175 - 0,0595 (0,6 m^) Do do, dien tich san siy la: 0,06 / 0,1 = 0,6 m^ Chpn kich thuoc san say 0,4 x 1,5 m Bp phgn cdp lieu vd thdo sdn phdm: Van kin kill dugc diing de viia dam bao tranh diit thoat nhiet \'a ap, vira dieu chinh dugc luu lugng cip Voi nang suat, ty trpng va kich thuac Ion nhat cua nguyen lieu mm, tinh dugc the tich nguyen lieu cannapm)ng gio bing Vi ^ / 175 = 0,143 m"' Lay chieu rpng dai van = 200 mm (gan bang b i rpng buong say de trai deu nguyen lieu) Do san pham co nang suat thap han chut it nen bp thao san pham sir dung tuang tu nhu bp phan nap lieu, d6 chi can tinh cho bp nap lieu Su dung bg trao doi nhiet ong chiim, tinh dugc tong dien tich be mat trao doi nhiet; F - Q / ( k N ATin)^7.877m^ Coi the tich cac canh van chiem cho la khong dang ke, lay duong kinh true van bang 62 mm duong kinh dinh canh la 75 mm, thi the tich bu6ng van la: V2 = 0,00028 m^ Do do, s6 vong quay ciia van n ^ 8,5 v/ph Chpn dgng co hop so v6 cap de co the dieu chinh dugc nang suat can, tai trgng hanh tac dung len cac canh van la qua nho nen bo qua tinh toan va chpn dpng co v6 cap 0.4 kW co san Bd phcin cung cdp nhiet: Tir dp am, nang suat yeu cau, tinh duac lugng nuac can bay hoi Gn = 23.16 kg HiO/h tir tinh dugc lugng nhiet can thiet de bay hen Iugng am la 115 800 kJ/h Toe dp toi thieu da xac djnh dugc la 1,3 m/s (CO sii dung bp phan rung) nen toe dp thiet ke se lay bang 1,3 x 1,5 = 1,95 m/s (chpn = m/s) Voi he s i thoang 60%, nen lugng tac nhan say can thiet de t^o soi dugc tinh: Chpn ong co duang kinh 58 min, va chieu dai ong 2,3 m, vai he so k = 1.5 thi s6 ong can thiit la: n = k X F / (TT X d X 1) - 30 Chpn quat say la quat ly tam 5,5 kW co luu lugng 6000 m^/li, 150 mmHjO Tir nhiet lugng da tinh, chgn hieu suat buong dot 0,9 va trao doi nhiet 0,6 xac dinh dugc lugng nhiet buong dot can tao ra: Qbd = 216.152 k.I/h Bp phdn phdi khi: De phan phoi dong deu tren mat san say san luai voi cac canh cliia gio dugc thiet ke nam pliia dLfoi Mat kliac, cac cira thoat ciia buong say dugc chia cira b i tri each deu tren trin buong say se giiip cho dong dan deu va vi \ay nguyen lieu se khong bj don nhu truang hgp bo m' mot cira thoat Bp hoi luu thai Mpt ong chiim nga dugc dat phia tren buong siy d i thu thai tir buong say Mgt van buom dieu chinli dupe dp ma de CO the hoi lim klii thai mgt phan hay toan phan Bp phgn tgo rung : Tlieo Pakowski [6], chpn CO dinh bien dp rung la 10 mm, va tin so dieu chinh dugc bang bp bien doi vo cip tir 160 -500 l/ph C6ng suat dgng ca rung tinh dugc Pd/^ = 1,5 kW TAP CHI CONG NGHIEP NONG THON - SO 12 - 2014 Hinh Mdy sdy tang sdi duac thiit ke che tgo KHOA HOC - CONG NGHE 3.4 Ket qua thir nghiem say hanh la tren may say thiet ke Sau dugc loai bo nhtrng la gia, lia, hanh la dugc rira sach, de rao nuoc r6i thai ngan - mm va cho vao may de say voi toe dp gio tren lap san 2,05 m/s, nhiet dp tac nhan say 70''C va bien mng 10 mm be day say 100 mm, voi cac chi dp ty le hoi luu va tin so rung khac Do hanh la c6 dp am ban dau kha Ion, giai doan dau nuoc lign ket tu boc hoi nhanh va nhiiu nen chi tiin hanh hoi luu sau bat dau siy 10 phiit Kit qua thir nghiem the hien bang 2,3 Bdng Anh huang cua ty le hoi luu vd tdn sd rung den thai gian sdy vd chi phi nang limng rieng Tan so rung, (lan/ph) 300 275 250 Ty le hdi lira, (%) 50 60 [ 70 Thai gian say, (phiit) 25 25 26 25 25 26 25 25 26 Ty le hoi luu, (%) 50 60 70 Chi phi nang luong rieng, (kWh/kgHzO) 1.160 1,166 1,920 1,141 1,135 1,164 1,149 1,142 1,168 Bang Anh hirdng ciia ty le hoi luu vd tdn so rung den chdt luc/ng mdu vd miii Tan so rung, (lin/ph) 300 275 250 50 Xanh tu nhien, thom Xanh tu nhien, thom Xanh tu nhien, thom Ty le hii luu, (%) 60 Xanh tu nhien, tham Xanh tu nhien, tham Xanh tu nhien, thom Chi phi nang lugng rieng giam di tang ty le hoi luu tit 50% len 60% tiSt kiem duoc nhiet luong tir thai Tuy nhien, h6i luu 70% thi chi phi than tang len nhi^u hoi am hoi luu lai nen chi phi nang luong rieng tang Khi tang tan so rung tir 250 len 275 l4n/ph thi thai gian say hau nhu khong giam nhung chi phi nang luang rieng lai giam su ho tro soi nguyen lieu tdt han Khi tang ti6p len 300 ISn/ph thi chi phi nSng luong rieng lai ting su ho trg Ai nguyen lieu qua soi la khong can thiSt, thoi gian say duong nhu khong thay d6i, nang lugng cung cSp de rung lai tang len CJ tat ca cac che ta thay chdt Iugng san pham sau say deu tot, xanh tu nhien va co mui thom dac tnmg Nhu vay, hanh la dugc s4y theo qu> trinh cong nghe nhu sau: 70 Xanh tu nhien, tham Xanh tu nhien, thom Xanh tu nhien, thom (T Nguyen li?u + L\ra chpn Rua, lam sach J) | i \ i Th^i ngan 3-5cm i Say 70°C; toe ^io l,3m/s; b6 day say lOcm; rung 275 lan/ph; bien dp lOmm; hoi luu 60% sau 10 phut dSu; thoi gian say 25 phiit L^m nguoi 06ng goi San pham Hinh .Sa dd quy trinh cdng nghe sdy hdnh td 20 TAP CHi CONG NGHIEP NONG THON - SO 12 - 2014 KHOA HOC - CONG NGHE 3.5 Sa bo so sanh chi phi say Tren co sa du lieu cung cap tir cac nguon, chi phi nang lugng rieng cung nhu chi phi siy cho I kg san pham (chua tinh von va khau hao thiet hi) dugc tinh toan Say theo phuang phap tmh vi ngang truyen thong co chi phi nang lugng rieng tuang tu nhu say theo cong nghe ting soi va mac dii chi phi say thap han nhung chit Iugng san pham ve mau va miii kem: mau xanh tii, kem thom Say theo cong nghe tang soi CO chi phi say cao nhung chat lugng san pham t6t han va dac biet thoi gian say ngan ban nhieu cung giiip giai quyet van de thai vu Bdng Sa bp so sdnh mpi sd phwmgphdp sdy sdy hcinh Id Phuong phap say Do am cuoi, Thai gian say, (h) Chi phi nSng lugng rieng, (kWh/kgH,0) (d/kg san pham) 1,138 3460 0.653 4463 (%) Say tTnh vi ngang truyen thong' 10 Say h6n^ ni>oai~ 5,2 Say bcfm nhiet' 10 10,5 Say tang soi Chi phi say, Chat lucmg mau miii (danh gia cam quan) Xanh toi, Item thom Xanh thSm, Iham Xanh tir nhien, tham 10 0,42 1.137 5179 Xanh tu nhien, tham Tinh tren CO SO ligu cung c ^ boi gia dinh 6iigNgL>CT Van Ben lliyy Tra Nam Trung Nam Sach Hai Dutmg ^ sa lieu ciia Pham van Tfiy DH Bach Kho-i ila Ngi ^ Bdo cao khoa hgc 2003 "Nghien ciJu quy Irlnh va thiet hi say sach rau qua bang biTm nhici" IV KET LUAN Nghien cuu da tim toe dp tac nhan say hanh la phii hgp la 1,6 m/s, nhiet thich hgp la TO^C May say tang s6i dugc thiet ke va che tao g6m: 16 dot than da vai bp trao doi nhiet, bp phan phoi khi, bp phan cap lieu va Ihao san pham, bp phan hoi luu thai, san say vai co cau rung de ho trg soi ban dau nguyen lieu c6n qua am, lam giam toe dp tac nhan xuong 1,3 m/s Sau thii nghiem say tren may, da xa} dung dugc quy trinh say hanh la nhu sau: nhiet dp tac nhan say 70''C, toe dp tac nhan 1,3 m/s, tin si rung 275 I/ph (bien dp 10 mm), be day siy 100 mm, thoi gian say 25 phut, hoi luu 60% thai Qua tinh toan chi phi nang Iugng rieng, chi phi siy va so bp so sanh vai mgt so phuang phap siy hien diing siy hanh la, siy theo cong nghe ting soi co chi phi say lan hon song lai CO chat lugng cao hon va thoi gian say giam dang ke TAI LIEU THAM KHAO [ I ] Asoka A.P.B.E Tennekoon 1987 Fluidized bed dryer for parboiled paddy in Srilanka RNAM Newsletter 30 Dec 1987 [2] Gao J.Z.H., D.B Gray, R Molheram and M.A Hussain 2000 AAPS Pharmaceutical Science Technology 1(4) [3] Grabowski S., M Marcotte and H.S Ramaswaniy 2003 Drying of Fruits, Vegetables and Spices, tn: IHandbook of Postharvest Technology - Edited by Chakraverty A., A.S Mujumdar, G.S.V Raghavan and H.S Ramaswamy New York, USA [4] Kudra T and G,l Efremov 2002 A QuasiStationary Approach to Drying Kinetics of Fluidized Particulate Materials IDS 2002 Proceedings [5] Liukov A.V 1968 Ly Ihuyit say Moscow [6] Pakowski Z., Mujumdar A.S and C Strumillo 1984 Theory and application of vibrated beds and vibrated fluid beds for drying processes In: Advances in drying, Vol 3, edited by Mujumdar A.S Washington D.C, pp.245-306 [7] Soponronnarit S 1994 Drying of paddy and maize in Thailand In: Postharvest Technology for Agricultural Products in Vietnam (Editors Champ B.R an'd Highley E.) ACIAR No.60-Proceedings of an Intemational Workshop held at Hanoi - Dec 1994 [8] Soponronnarit S, T Swasdisevi, S Wetchacama and W Wutiwiwatchai 2001 Fluidised bed drying of soybeans Stored Product Research Apr, 37 (2): 133-151 [9] Soponronnarit S va Prachayawarakom S 2003 Nghien ciiu va phat trien ve say liia o Dong Nam A Hoi thao-Tap huan Cong nghe say ASEAN Tp H6 Chi Minh, Viet Nam pp 73-90 Ngay nhan bai: 15/02/2014 Ngay phan bien: 28/02/2014 Ngu-oi phan bien: TS Nguyin Van Doan Vien Co dien Nong nghiep va Cong nghe sau thu hoach TAP CHi CONG NGHIEP NONG THON - SO 12 2014 21