KHOA HQC - CONG NGHE
THIET KE CHE TAO VA THlf NGHIEM THIET Bj CHAN CA COM HOAT DONG THEO NGUYEN LY LIEN TUC
Le Anh Birc , Nguyen Thanh Phong TOM TAT
Nghiin cuu dtrgc thuc hien nhdm tinh todn thiel ke va che tgo thiet bi chdn cd cam hogt dgng theo nguyen ly chdn lien tuc ndng sudt 20 kg/h. Kit qud tinh todn thiet ke dd xdc dinh duffc cdc thdng sd cua thiit hi chdn, cdc thdng sd van hdnh cua thiit bi dugc cdi dgt vd gidm sdt tu ddng theo yeu cdu su dung. Thiit bi chdn cd cam dd dugc chi tgo theo cdc kit qud linh todn. Trin ca sa ddnh gid chdt luffng cd cam sau khi chdn, kit qud khdo nghiam tgi cdc mirc nhiit dg chdn 85 - 95"C vd thdi gian chdn 60 -180 gidy da xdc dinh dugc che do chdn phii hgp tgi nhiet dg chdn 85°C vd thdi gian chdn Id 120 giay, cd cam sau khi chdn cd hdm lugng dgm tdng dgt 3,69%, chdt lugng ddnh gid cdm quan dgt yiu cdu, chi phi di^n ndng rieng cho qud trinh chdn 0,135 kWh/kg cd cam.
Tie khod: cdcam, nhi^t dg chdn, thdi gian chdn, chi phi di0n ndng rieng.
STUDY ON DESIGNING, MANUFACTURING AND TESTING OF CONTINUOUS PARBOILING MACHINE FOR ANCHOVY
Le Anh Due', Nguyen Thanh Phong^
SUMMARY
This study was performed to design and manufacture a continuous steamer for anchovy. The continuous steamer for anchovy with capacity of 20 kg/hour was manufactured based on calculating parameters. The operating parameters ofthe steamer are installed and monitored automatically. Based on assessment quality of steamed anchovy, the experimental results at steaming temperature range form 85 °C to 95 °C and steaming time range from 60 seconds to 180 seconds determined the suitable steaming regime at steaming temperature of 8 5 X and steaming time of 120 seconds, the quality of anchovy met Vietnamese standard, protein content of steamed anchovy reaches 3.69%, specific electric consumption for steam process of 0.135 kWh/kg.
Keywords: Anchovy, steaming temperature, steaming time, specific energy consumption.
I. DAT VAN DE
Ca com la loai ca cd chiia rat nhieu dam, ciia ca khdng bi hoac it bi bien ddi, qua trinh chdt beo loai Oiiiega-3, cac khoang chat nhu chan (xii ly nhiet) cdn lam thay ddi cau true thit canxi, sdt, selenium va cac vi chat dinh dudng ca gliip qua trinh lam khd ca d cong doan ke khac. Ci nudc ta, ca cam tap trung nhieu t^i cac tiep dien ra nhanh han, ngoai ra tac dung cua tinh midn Tnmg va Nam Bp, dac biet d cac nhiet con lam giam lugng vi sinh vat bam tren vung bien Quang Ngai, Ninh Thuan, Phii Yen, b i m a t cua ca [2].
Nha Trang, Phan Thilt, Vung Tau, Phu Qudc... j u y nhlen thuc t l hien nay tai cac c a sd c h l va day la loai hai san dac trung ciia cac tinh nay. bjgn ca cam, viec c h ^ ca dugc thuc hien thu Trong quy trinh che bien ca com khd yeu cdng theo tung me, nhiet do nudc chdn va thdi cdu phai qua cong doan chan ca com truoc khi gjan chan ca la hai yeu t6 quylt dinh d i n chat phoi hoac sdy kho. Muc dfch ciia cdng doan lircmg ca sau khi chdn dugc xac dinh bdng kinh chan la lam vd hoat cac enzyme de lara ngung nghiem cua ngudi thao tac. Ben canh dd, do dac qua trinh sinh hoa xay ra trong ca, giu mau sac thii ciia viec chdn ca theo me nen chit lugng ca ' PGS.TS. Tmong Dai hpc Nong lam TP.H6 Chi Minh. cua moi me chan rat khac nhau va chdt lugng ca
^ThS. Tnrong D^i hpc N6ng lam TP.H6 Chi Minh. trong mpt me chan cung khac nhau. Ngoai ra
TAP CHi CONG NGHIEP NONG THON - SO 19 - 2015 3
I
KHOA HQC - CONG NGHJl ngudi van hanh phai lam vi|c trong moi trudng
rdt ndng hue va nguy hilm.
D I giai quylt cac tdn tai neu tren nham giam lao dgng nang nhpc cho ngudi van hanh, nang cao nang sudt va chat lupng ca sau khi chdn, dam bao ve sinh an toan thirc pham va dap ling dupc yeu cdu xuat khau thi viec xay dung cdng nghe va thilt bi chdn nguyen lieu ca com cho cac ca sd chl bien ca com nhdm phuc vu nhu cdu tieu dimg ngay cang tang cua thi trudng trong nudc va xuat khdu sang cac nudc khac tren the gidi la rat cdn thiet.
n. PHlTONG PHAP NGHIEN CUtJ
- Phuang phap tinh toan thiet ke: ke thua cong trinh nghien ciiu cd liSn quan den pham vi nghiSn ciiu. Tham khao cac tai lieu chuyen nganh, cdng nghe va thiet bj chan hien dang dugc sii dung, cac dac tinh cua ca com, ly thuylt vl truyen nhiet [l]... de lam co sd cho viec tinh toan va thiet ke.
Viec tmh toan thilt ke budng chan dua vao ly thuyet tinh toan may van chuyen lien tuc dang bang tdi, nang sudt thiSt ke, thdi gian chan va khdi lugng the tich cua ca cam...; tinh toan cdng sudt bg gia nhiet dua vao iugng nhiet cdn thiet, lugng nhiet tdn that...; cac thiet bi dan ddng dugc tinh toan theo ly thuyet tinh toan chi tiet may va hS ddn ddng co khi [3].
- Phuang phap che tao: dua vao yeu cdu ky thuat ciia ban ve thiet ke, may dugc che tao don chiec theo timg hg chi tiet dien hinh. Mdt s6 chl tiet tieu chudn dugc chpn mua tren thi trudng.
- Phuong phap do dac trong thuc nghiem:
cdc thdng sd cd the do true tiep nhu nhiet do, vdn toe bang tai chdn... dupc do dac bdng cac dung cu do chuyen dung, cac thdng sd cdn lai dupc xac djnh thong qua cac cdng thiic quy ddi.
Thdi gian chan dugc xac dinh dua vao van tdc bang tai chan thdng qua bien tdn ma hlSu Invt CHFIOOA, tdn sd 0-120 Hz.
4 TAP - Cac tham so thdng ke nhu gia tri trung binh, dg lech chuein, khoang tin cay dugc sir dung dl xu 1;^ cdc kit qua thirc nghiem. Kilm tra sy khac bi?t cua cac s6 U?u thi nghiem vl mat thong ke dugc xu 1;^ bdng phuong phap LSD (Least Significant Difference - Gidi han sai khac nhd nhdt)
- Vat lieu chan la ca cam tuoi, chilu dai trung binh cua thdn ca 60 - 65 mm. Dung dich chdn la dung dich nudc mudi ndng do 3%.
Chdt luong ca com sau khi chdn dugc kiem dinh ham lugng dam tdng theo TCVN 8134:2009, kilm tra E.coli theo TCVN 6848:2001 va ddnh gia cam quan ve do chin va nguyen ven cua ca sau khi chdn [4].
III. KET QUA VA THAO LUAN
3.1. Ket qua tinh toan thiet ke va che tao a) Cac sd lieu thiet ke ban ddu;
Nang suat thiet ke 20 kg/h, hoat ddng theo nguySn ly chan lien tuc.
B6n chan dun sdi dung dich nudc bdng dlSn trd, nhiet do dung dich chdn: 95''C.
Thdi gian chdn: 2 phiit (khoang thdi gian tir khi ca com ngap vao dung dich chdn cho dSn khi ra khdi dung dich chdn). Tuy nhien, khi thiet ke yeu cdu phai (Seu chinh dugc thdi gian chdn theo yeu cau trong phgm vi dao ddng tii 1 - 3 phiit.
b) Kit qua xac dinh nguyen ly cau tao va nguyen ly lam viec cua may:
Nguyen ly cdu tao ciia thiet bi chdn ca cam hoat ddng theo nguyen ly chdn lien tuc dugc trlnh bay tren hinh 1.
Dpng CO (14) hoat ddng keo bang tdi (2) chuyln dgng, dilu chinh tdc do ciia ddng ca bdng biln tdn (15). Cai dat nhiet dg cho bdn chdn, dien trd (10) hoat d^ng dun ndng dung dich chdn din nhi^t do cai dat. Ca cam dugc cap len bang tai tgi vi tri cua vao bdn chdn. Bang tai (2) se tai ca cam di chuyln di ngdp vao dung dich chdn qua sudt chilu dai bdn chdn (11) va di CHI CONG NGHIEP NONG THON - SO 19 • 2015
KHOA HQC - CONG NGHE
Ctra vao
m^--w""v^m
Hinh 1. Nguyen ly cdu tgo thiet bi ckdn cd cam
1. Tang chu dong; 2. Bang tai chan bing lirdi inox; 3. Nap bon chija dung djch chSn; 4. Con ISn gift bSng tai; 5. Tang bi d^ng; 6. Tryc cang bang tai; 7. Khung dd bon ch^n. 8. 6ng xa dung dich; 9. Khung thilt bj; 10. CAc dien trit; 11. B6n
chiia dung dich; 12. Cdc cam bien nhi?t dp; 13. Bp dieu khiln; 14. B6ng ca; 15. Bien tan.
het chieu dai bdn chan. Cd cam dugc chan chin va di chuyen ra ngoai d phia ciia ra. Ben duoi bdn chan dugc bo tri van xa nudc nham thao bd nudc sau moi dgt chan va ve sinh bdn chdn.
Nhiet dp cua nudc dung dich chan dupc cdi dat, hien thi vd gidm sat tu dpng.
c) Ket qua tinh toan thiet ke:
Bang tai chdn ca com dugc thiet kS dang bang phang bang ludi uiox 304 cd dudng kinh sgi 1 mm de van chuyen ca cam qua bon chan.
Can Cli vao khdi lupng the tich cua ca, kich thudc ca, nang suat thiet ke va thdi gian chdn, ket qua tinh toan xac dinh dupc chieu rpng bang tai 200 mm, van tdc bang tai 0,005 m/s. Chieu dai phdn bang tai chdn ngap trong dung dich chan la 600 mm, Vdi be day ldp ca cam tren bang la 10 mm thi tai trgng vdt Heu tren 1 met chieu dai bang la 1,4 kg/m.
Vach bdn chiin cau tao gdm 3 ldp, ldp ngoai la inox day 0,4 mm, gjGa la ldp each nhiet day 20 mm va vach trong la inox day 0,8 mm. Bdn chua dung dich chan cd kich thudc: dai x rdng x cao TAP CHI CONG NGHIEP NONG THON - SO 19 -
Id 800 X 220 X 100 mm, lugng dung dich can thiet chiia trong bdn la 12 lit, lugng nudc nay vua du de ngdp ldp ca com khi dl qua bdn chdn.
Ben tren bdn chan cd nap de han che sir thdt thoat nhiet trong qua trinh chan.
Ket qua tinh todn nhiet lupng: bao gdm nhiet lirgng can thiet de lam ndng ca den nhiet do chan la 1072 kJ, nhiet lugng de lam ndng nudc va duy tri nhiet dp nudc trong qua trinh chan 8634 kJ, nhiet lupng tdn thdt qua vach bon chan 165 kJ, lam ndng bang tai va cac bd phan ca khi 121 kJ. Vdy tdng cdng suat cdn thiet cung cap cho thiet bi chdn la 2,78 kW. Chpn 5 dien trd hinh chii U, cdng suat moi dien trd la 0,6 kW va bd tri dan deu 5 dien trd tai vi tri day ciia bdn chan.
Can Cli vao ket qua tinh toan tai trgng tren 1 met chieu dai bang tai, lyc can chuyen ddng va lyc keo cang bang... da xac dinh dugc cdng suat ddng ca truyen dpng cho bang tdi chdn la 0,1 kW. Sd vdng quay cua tang ddn dpng la 0,8
KHOA HQC - CONG NGH$
vdng/phiit, tuong ling vdi van tdc bang tai chdn la 0,005 m/s.
v l qua trinh cap va thao lieu ca com, do nghien ciiu d dang md hinh nen viec cap va thao lieu ca cam dupc thyc hien bang tay. Tai vi tri bang tai d dau cap lieu, ca com dugc rai deu len bang tai vdi chieu day tuong duong hai ldp ca.
Tai vi tri ddu ra lieu, ca cam thdnh phdm dugc thu bang mang hiing.
Bg dieu khien dugc tinh todn thiet ke ddm bao cdng sudt ciia thiet bi, cd the cai dat, hien
thi va giam sat nhiet dd ciia dung dich chin.
Van toe bang tai chdn dugc dilu chinh bdng biln thn hi$u SLANVERT, model SB70G2.2D2, pham vi 0 - 650 Hz, dam bao dilu chinh dugc vgn tdc bang chan theo yeu cdu.
d) Ket qua che tao:
Tir cac ket qua tinh toan va bg bdn ve thilt ke, thiet bi chan ca cam hogt ddng theo nguyen ly chan Hen tuc da dupc chl tao va ldp rap hoan chinh the hien trdn hinh 2.
Hinh 2. Thiet bi hdp cd cam ndng sudt 20kg/h 3.2. Ket qua khao nghifm
Kit qua khao nghiem sa bd cho thdy thilt bi chdn lam viec dn dinh, khdng xay ra hien tupng rd ri nudc cua bdn chdn, bang tai chdn chay em diu, khdng bi lech, bd dilu khiln va giam sat qua trinh chdn hoat ddng dat yeu cdu thilt kl.
Vdi luong nudc dung dich chdn la 12 lit theo tinh toan thilt kl, kit qua thi nghidm da cho thdy sau 18 phiit gia nhiet thi nhiet dp dung dich chdn dat 95°C, gdn diing vdi kit qud tinh toan thiet ke.
- Bd tri thi nghiem; ca cam trdng, tuoi, co chieu dai trung binh 60 mm, khdi lupng 10 kg cho mdi lan thu nghiSm. Dung dich chdn Id dung nudc mudi ndng dg 3%.
Cai dat nhiet dp dung dich chan va thdi gian chan (thdi gian chdn dugc xac djnh thdng qua viec didu chinh van tdc bang tdi chdn bang bien tan) theo cac miic yeu cdu ciia cac thi nghiem.
Mdi thi nghiem dugc lap lgi 3 ldn, cac gia tri dugc tinh trung binh tii 3 Idn lap lai.
TAP CHI CONG NGHIEP NONG THON - SO 19 - 2015
KHOA HQC - CONG NGHE De xac dinh su anh hudng cua nhiet dp chan
va thdi gian chdn din chdt lupng cua ca com sau khi chdn, tiln hanh thi nghidm chdn tgi 2 miic nhiet do chdn la 85 va 95°C va 3 miic thai gian chdn la 60,120 va 180 giay.
Kit qua xet nghiem ham lupng dgm tdng ciia ca cam sau khi chdn d nhiet dd 85°C vd nhiSt dd chdn 95''C tgi 3 miic thdi gian chdn thay ddi tii 60 -180 gidy dugc trinh bay trong bang 1.
Bdng 1. Kit qud xet dgm tong sau khi chdn tgi muc nhiet do 85°C
Nhiet d o chan
85°C
95"C
Tha gian (s) 60 120 180 60 120 180
chan D a m t o n g
(%)
3,74"
3,69"
3,32"
3,28°
3,06°
2,93"
Cac gia tri trung binh dugc xii ly thdng ke bdng phuong phap LSD: cac gia tri cd ky hieu chii khac nhau; khac biet co y nghia d miic y nghTa 0,05.
4.0 3.5 g 30
g* 2.5 S 1.5 1.0
*
Cac ttu n g h ^ m
1 (%5°C - 60 s); 2 (SS^C - 120 s); 3 (SS^C - 180 s);
4 (95''C - 60 s); 5 i95°C - 120 s); 6 (95''C - 180 s).
Hinh 3. So sdnh hdm lugrng dgm tong cua cd sau khi chdn tgi cdc che do chdn
6 nhidt do 85°C thdi gian chdn 60 s, theo danh gia cdm quan cd chua dgt dii dp chin cdn thilt. 6 nhiet dp 95°C thai gian chdn 180 s, cd CO hien tupng trdc phdn dudi, than va gSy dau.
Nhu vay d hai miic thdi gian chdn nay ca khdng dat yeu cdu ve cam quan. Cac mdu cdn lai nhin chung mau sac ca sau khi chan dep, thit chdc, nguyen ven, khdng bi bd, dat dp chin deu nen cdn phdn tich ham lugng dgm tdng de xdc dinh mau c6 ket qua tdt nhat.
Cdc kdt qua xet nghiem ham luong dam tdng cua ca sau khi chan tgi cac miic thdi gian chan va nhiet dp chdn khac nhau trinh bay trong bang 1 dugc xu ly thong ke dd cho thdy cd su khac biet ciia cac sd lieu d miic y nghTa 0,05.
Nhu vdy vdi cac miic thdi gian chan va nhiet dp chan khac nhau cd anh hudng din chdt lugng cua ca sau khi chan.
Ket qua trong bang 1 cho thdy ngogi tru tai hai ch6 dd chan ca khdng dat tieu chudn cam quan thi d che do chan vdi nhiet dp 85°C vd miic thdi gian 120 s cho ket qua ham lugng dgm tdng cao nhdt la 3,69%, so vdi ham lugng dam tdng trong ca tuoi trudc khi chdn la 3,84%, nhu vay che do chdn nay dat ket qua tdt nhdt, phu hgp nhdt trong sd cac che dp chdn da thu nghiem. Ket qua kiem tra ham lugng E.coli trong cd sau khi chdn cho thay khdng phat hien E.coli.
Tren ca sd chd dd chdn nay, tien hanh danh gia chi phi dien nang rieng cho qua trinh chan nhdm xac dinh sa bg hieu qua cua thiet bi. Ket qud dugc trinh bay trong bang 2 cho thdy miic tieu thu dien nang ridng tnmg binh cho qua trinh chdn la 0,135 kWh/kg ca com.
Bang 2. Tieu thu dien nang rieng cho qud trlnh chdn S6 me chan
Chi phi dien nang rieng, kWh/kg 1 0,144
2 0,120
3 0,139
4 0,146
5 0,124
TB 0,135
TAP CHl CONG NGHIEP NONG THON - SO 19 - 2015
KHOA HQC - CONG NGHE D^ uac luong dp bien dgng cua muc tieu
thu dien nang rieng cho qua trinh chSn ve mat thdng l<e, do lech tiSu chuin thuc nghiem cua miic tieu thu dien nang riSng cho qua trinh chan duoc xac dinh bang cong thiic:
I(Ari-Ar)2 -1
- 0,00014 kWh/kg ca com Trong dd:
An: miic tieu thu dien nang rieng ciia me chan thii i.
Ar: miic tieu thu dien nang rieng tnmg binh cua cac me chdn, Ar = 0,135 kWh/kg ca.
n: sd mdu (sd me chdn), n ^ 5.
De bidu dien dp dn dinh cua cac ket qua thi nghiem, khoang tin cay (vimg phan bd) cua miic tieu thu dien nang rieng cho qua trinh chan dupc xdc dinh bang cdng thiic:
Ar-t, / 2 . - = < A r < A r + t ; 2 . - ^
vn Vn Trong do:
p: miic y nghia, p ^ 0,05.
tp/i: chudn so theo tieu chudn Student tra theo sd bac tu do (n - 1) va miic y nghTa p/2.
0 , l 3 5 - 2 , 7 7 d ^ ^ 4 < A r < 0 , 1 3 5 + 2 , 7 7 6 ^ ^ ^
Vs ^/5 0,1348 kWh/kg < Ar < 0,1352 kWh/kg
Vdi ket qua nhu tren, quy ddi tren 1 tan ca cam thi chi phi dien nang ridng cho chan 1 tdn ca com la 135 kWh/tan.
IV. KET LUAN
Tren co sd danh gia thuc trang viec chan ca com trong quy trinh che bien ca com khd va phan tich uu nhupc diem ciia cac cdng nghe va thiet bi chan hap thuy hai san trong va ngoai nudc, nghien ciiu da xac dinh dupc nguyen ly cdu tgo va nguyen ly lam vide cua thilt bi chdn cd cam hoat dpng theo nguyen ly chdn lien tuc.
Kit qua tinh toan thilt kl thilt bi chdn ca cam
nang suat 20 kg/h da xac dinh dupc cac thdng sd ciia thilt bi chdn, thilt bi cd cdu tgo don gidn, de van hanh, cac thdng sd van hanh cua thilt bi dupc cai dat va giam sat tyr ddng theo yeu cdu Sli dung. Thilt bi chdn ca com da dugc chl tgo tren co sd cac ket qua tinh toan thilt kl. Kit qua khdo nghiem so bp dd cho thdy cac kit qua khao nghiem phu hpp vdi cac kit qua tinh toan.
Nghien ciiu da tiln hanh thi nghiem chdn tai cac miic nhiet dp chan va thdi gian chdn khac nhau nham xac dinh sir anh hudng cua nhiet dd chdn va thdi gian chdn din chdt lupng cua ca com sau khi chdn tren co sd danh gid ham lupng dgm va danh gia cam quan theo Tieu chudn Viet Nam. Cac sd lieu khao nghiem dupc x^ ly thdng kd da xac dinh dupc chl dp chdn phu hop tai nhiet dp chan 85°C va thdi gian chdn la 120 gidy, ca com sau khi chan cd ham lugng dgm tdng dat 3,69%, chdt lugng ddnh gia cdm quan dat yeu cdu, chi phi dien nang rieng cho qua trinh chan 0,135 kWh/kg ca com. Tuy nhien, can tiep tuc nghien ciiu quy hogch tfiuc nghiem nham xac dinh che dp lam viec tdi uu cho qua trinh chan ca cam.
Tai lieu tham khao
1. H o ^ g Dinh Tin, 2007. Tmyln nhiSt va tfnh toan thilt bi trao doi nhiet, Nha xu3t ban Khoa hpc va Ky thuat.
2. Nguyin Hay, 2003. Nghien cihi thay dli nhien lieu cho 16 hip cd cam tai tinh Ninh Thu$n. €)e t^i cap Tinh Ninh Thugn.
3. Trinh Chit, Le V5n Uyin, 2006. Tinh toan, thiat kS he dan dpng ca khf, tap 1 vli 11. N h i xuat ban Giao Due.
4. Vu K l Hoach, Le Anh Dii'c, 2013. Nghian even thiet k l clie tao va xdc dinh che do cong nghS toi uu thiet bi hkp hai san lam viec Hen tuc, nSng suat 50 kg/h. T?p chi Nflng nghiap v^ Phdt trien n6ng thfln, s6 7/2013, trang 42 - 45.
N g a y n h a n b a i : 08/8/2015 N g a y p h a n bien: 20/8/2015
N g u 6 i p h a n b i | n : P G S T S . Chu Van Thien, Vign C a dien n o n g nghiep va Cong nghfi sau thu hoach, TAP CHi CONG NGHIEP NONG THON - SO 19 - 2015