Doc thiet ke may rang ca phe nang suat 2

TOM TAT LUAN VAN Ca phe la mot nhung thuc uong tu lau doi co gia tri dinh duong cao Viet nam la mot nhung nuoc xuat khau ca phe kha lon tren the gioi Tuy nhien gia tri ca phe cua nuoc ta khong cao vi xuat khau tho va chat luong che bien kem so voi the gioi Do muon nang chat luong phai dau tu nang cao thiet bi che bien Nhung gia ca trang thiet bi cua nuoc ngoai lai qua dat Vi the voi muc tieu nang cao chat luong san pham, gia thanh, em da co gang tim toi, hoc hoi de thiet ke chiec may rang ca phe dap ung nhu cau cua thi truong Luan van duoc sap xep theo chuong nhu sau: Chuong -Tong quan: Gioi thieu so luoc ve ca phe va quy trinh che bien Chuong -Thiet ke nguyen ly may: Lua chon phuong an rang ca phe va gioi thieu mot so may rang ca phe co san tren thi truong Chuong -Tfnh toan ket cau may: Tinh toan va lua chon cac bo phan may rang ca phe Chuong -Tfnh toan nhiet: Tinh toan nhiet luong can cung cap cho qua trinh rang va chon dien tro gia nhiet Chuong -Thiet ke mach dien: Thiet ke va lua chon cac thiet bi dien cho may rang ca phe Chuong -Bao tri bao duong : Trinh bay cac bien phap bao tri, bao duong may rang Chuong -Ket luan : Banh gia, nhan xet va neu len cac diem can khac phuc cua may rang ca phe MUC LUC De muc Trang Nhiem vu luan van 7.1 TAI LIEU THAM KHAO CHtfONG TONG QUAN 1.1 Gifri thieu ve ca phe Tu "ca phe" tieng Viet co goc tu chu cafe cua tieng Phap Ca phe la mot loai thuc uong mau den co chua chat caffein va duoc su dung rong rai, duoc san xuat tu nhung hat ca phe duoc rang len, tu cay ca phe Ca phe duoc su dung lan dau tien vao the ki thu 9, no duoc kham pha tu vung cao nguyen Ethiopia Tu do, no lan Ai Cap va Yemen, va toi the ki thu 15 thi den Armenia, Persia, Tho Nhi Ky va phia bac Chau Phi Tu the gioi Hoi giao, ca phe den Y, sau la phan lai cua Chau Au, Indonesia va Mi Ngay nay, ca phe la mot nhung thuc uong thong dung toan cau Hien nay, cay ca phe duoc tai hon 50 quoc gia tren the gioi, co mot so nuoc xuat khau ca phe Hat ca phe duoc lay tu hat cua cac loai cay thuoc ho ca phe (Rubiaceae) Ba dong cay ca phe chinh la Coffea arabica (Ca phe Arabica) - ca phe che, ca phe Blue Mountain Coffea canephora (Ca phe Robusta) - ca phe voi Coffea excelsa (Ca phe Liberia) - ca phe mit voi nhieu loai khac Chat luong hay dang cap cua ca phe khac theo tung loai cay, tung loai hat va noi khac Ca phe Robusta duoc danh gia thap hon so voi ca phe Arabica co chat luong thap hon va gia ca theo cung re hon So voi Robusta, Arabica doi hoi duoc gieo o nhung vung dat cao hon, co kh hau mat me hon (khoang 3,000 - 6,000 feet so voi muc nuoc bien) Ca phe Arabica cho mui vi ngon hon nhung cung la loai "kho tmh" hon Robusta Thai gian de qua ca phe Arabica chm lau hon, san luong cung thap hon, nhien Arabica lai cho nhung hat ca phe co mui vi thom ngon hon, chmh vi the gia cua no cung cao gap doi so voi Robusta Trong do, Robusta duong nhu "de chiu" hon, loai ca phe lai ua thmh dieu kien kh hau am va kho hon, cao ly tuong khoang 2,000 feet so voi muc nuoc bien Nhu chmh ten goi cua minh, Robusta co suc phat trien manh me va kha nang chiu dung cung that dang ne nhung dieu kien bat loi ma Arabica se tan lui Su phoi tron giua Arabica va Robusta duoc tien hanh nham tao nen su can bang va phong phu cho tach ca phe Tinh chua cua Arabica ket hop voi the chat dam da cua Robusta se tao nen mot loai ca phe hoan hao 1.2 Quy trinh cong nghe Thu hoach: Viec hai ca phe dugc thuc hien co the bang tay hoac bang may May dugc su dung tren nhung nong trai ca phe lon, hay vung dat phang- da so o Brazil Cong viec hai bang tay dugc ap dung o nhung nong trai nho voi ph lao dong thap Che bien: Co phuong phap che bien chu yeu Phuong phap che bien Kho thudng dugc ap dung rong rai tai Chau A, Braxin va chau Phi Phuong phap che bien Uot thi tap trung o khu vuc Trung va Nam My Phuong phap che bien Kho: trai ca phe dugc phoi kho duoi nang trdi tren nen san xi mang hoac gach cua cac nong trai, va se dugc dao tron lien tuc cho kho deu Sau khoang tuan ca phe se dat kho mong muon Khi may boc vo se dugc su dung nham loai bo lop vo qua Phuong phap che bien Uot: Trong Phuong phap che bien Kho tach bo lop vo thit sau trai ca phe dugc phoi kho thi Phuong phap che bien Uot lop vo thit se dugc lam sach va lam mem va tach bang may xat vo Trai ca phe sau loai bo lop vo thit se dugc u len men 24 - 36 gio, cong doan se lam mat di lop chat nhay Tiep den, hat ca phe dugc phoi tren nen san xi mang hoac dugc say kho bang may Sau do, may boc vo se giup boc di lop vo thoc Phuong phap che bien Kho don gian, it ton nang lugng nhan cong nhung phuong phap co nhieu han che la phu thuoc vao dieu kien thoi tiet No chi phu hgp voi noi co dieu kien mua h nang nhieu, khong dap ung dugc nhung yeu cau ve mat chat lugng Phuong phap che bien uot phuc tap hon ton nhieu thiet bi va nang lugng hon dong thoi doi hoi day chuyen cong nghe cung nhu thao tac ki thuat cao hon Nhung phuong phap thmh hgp voi mgi hoan canh, mgi hau thoi tiet Bong thoi rut ngan dugc thoi gian san xuat, tang nang suat cua nha may va nang cao chat lugng san pham cua ca phe nhan Hien o nuoc ta cac xi nghiep san xuat ca phe nhan chu yeu su dung phuong phap Kho (phuong phap co dien) Qua ca phe k i— -V Hai va bao quan k yV Phan loai lam sach XX Lam rao A Rua C N A Xat tuai C N Xat kho k 1^ V k Ca phe nhan Trich ly 1^ Say V k 1^ Loc ba V Hmh 1.1: Quy trinh che bien ca phe 1.3 Khai niem rang ca phe Rang ca phe la mot qua trinh ma nhung hop chat chua mui vi cua ca phe duoc giai phong nho mot loat cac phan ung hoa hoc Huong vi, chua, dam nhat va du vi cua ca phe phu thuoc rat nhieu vao qua trinh Qua trinh rang ca phe trai qua cac giai doan sau: 1.3.1 Hat ca phe Hat ca phe luc chua rang thuong co mau xanh ngoc rat dep Nhiet binh thuong, khoang 22-25 C Luc song, goi la ca phe nhan, ban than hat ca phe da co mot mui thom dac trung de chiu tuong tu nhu mui thao duoc, mui cua thuoc nam, mui cua hoa co kho „ Hinh 1.2: Hat ca phe luc chua rang r 1.3.2 -\ r Bat dau rang den nhiet tren 100 C Khoang thdi gian dau cua qua trinh Hinh 1.3: Hat ca phe bat dau rang den nhiet rang la de truyen nhiet cho hat ca phe Hat tren 100o C ca phe tu tu nong len dan va bat dau boc hoi nuoc chua ben trong, hat ca phe hoi teo lai va hau nhu co rat it su thay doi Trong giai doan nay, bi quyet rang ca phe ngon la tranh cho hat ca phe chai cung bang cach rang the nao de tao dong khong kM nong doi luu toi da trong rang va viec chuyen giao nhiet dien hieu qua nhat va lan nhiet dong deu den moi hat ca phe CHGONG TONG QUAN 1.3.3 Giai doan hat ca phe chuyen sang nga mau vang nhat - nhiet tren 150o C Luc nay, hat ca phe van tiep tuc hap thu nhiet, boc hai nuac va bat dau co su thay doi chut it ve the tich Trong giai doan tu lo rang lan toa mot mui tham nong cua co tuai va ram kho hoa quyen rat dac trung Tu hat ca phe nong toa mui huang cua cay co, cua canh dong, vuon cay ram mat, lam ta nha den que nha xa xoi, va tinh Hat ca phe dang giai doan thu nhiet rat nhanh va thay doi kfch thuac de chuan bi cho giai doan no dau tien 1.3.4 Giai doan vang dam - nhiet khoang 180o C Hat ca phe nga sang mau vang dam, hinh dang bat dau thay doi, the tich gia tang tu 20-30%, be mat hat bat dau co cac gan noi len Luc mui huang toa giong nhu la mui cua banh mi chay, mui go chay, mui cua dat mai sau can mua dau mua, co ca mui cua cu khoai lang nuang timg lam ta hoi be co lan them thuong mnn I J : nai cupnv cnuyen sang mau vang dam 1.3.5 Giai doan chuyen sang mau nau nhat - nhiet khoang 200o C CHGONG TONG QUAN Chuan bi cho giai doan phat tieng no dau tien cua hat ca phe Hat ca phe cang no lan nhanh chong, mui tham da chuyen qua mui ngot ngao giong nhu mui qua chin, nhu mui cua mat ong, lai thoang thoang mui cua mach nha Tuy nhien, luc cac phan ung hoa hoc van chua xay hoan tat, cac phan tu huang van chua duqc giaiphong va cau true sai cua hat ca phe van rat ben chat Neu luc lay hat xay bot va pha uong thi vi cua ca phe luc kha la chua va mui ca phe van chna tinh te, va co mui ngai ngai, nong nong Hinh 1.6: Hat ca phe chuyen sang man nan nhat 1.3.6 Giai doan chuyen sang mau nau - nhiet tren 200o C Cac tieng no bat dau vang len thung quay cua lo rang Cac phan nng hoa hoc qua tac dung nhiet xay bat dau dot chay cac tinh the dndng hat ca phe tao mau nau caramen, mui cua dndng mach nha cang luc cang ro, viec xay la mot phan nng hoa nau thnc pham dudi tac dung nhiet duoc goi la phan ung Maillard Qua phan ung Maillard thuc pham trd nen thom ngon hon va bat dau bien doi mau sac sam hon 1.3.7 Giai doan no lan thu nhat Hinh 1.7: Hat ca phe chuyen sang man nhiet khoang 210o C nan Tai thdi diem nay, cac tieng no ron CHGONG TONG QUAN cua hat ca phe da vang len nghe rat vui tai thung quay Ngudi rang ca phe, vdi su nhay cam, luon mong chd nghe tieng no than thuong Nhiet tang len nhanh Hat ca phe co nhieu bien doi ve hinh thuc, pham chat lan huong vi Khoi bat dau toa nhieu hon, mui thom ngao ngat toa ra, hap dan Tu thdi diem CHtfONG TONG QUAN tra di, qua trinh rang trd nen sinh dong, hat ca phe bat dau bnoc vao giai doan chin de cho san pham theo y dinh cua ngndi tho rang, ngndi tho rang thi van dung tat ca cac giac quan lan tam hon say me cua minh de cham soc, nang niu cho me rang nhn nang niu cong trinh nghe thuat cua rieng minh 1.3.8 Giai doan ngung tieng no - nhiet khoang 215o C Giai doan no dau tien la mot phan ung toa nhiet Sau thdi gian hap thu nhiet thi qua viec na lon dot ngot ve the t^ch, tang len den khoang 150%, lnong giam tn 10- 17 % va tao hang loat tieng no gion tan ron ra, nhiet lnong ben hat thoat nhanh chong Ke do, lap tnc hat ca phe lai bat dau giai doan thu nhiet Do qua trinh rang, sau lan no thu nhat, se can co them giai doan ngan de hat ca phe thu them nhiet lnong nham tiep tuc dnoc nung nong va dnoc bien Hmh 1.9: Hat ca phe a giai doan ngung tieng no doi.Vi the, qua trinh rang, tieng no reo vui lan thu nhat bong nhien giam xuong roi ngnng lai Luc phan ung caramen xay nhanh chong Cac phan ung hoa hoc lam phat sinh mui vi thom ngon cua ca phe cung xay ra, khoi boc len kha nhieu Ve hinh thuc hat ca phe sau na rong k^ch thnoc thi hoi thu lai va xuat hien cac vet nhan, nut phia ben mat dnoi cua hat 1.3.9 Giai doan sau ngung tieng no lan mot - Nhiet khoang 220o C Vao luc nay, hat ca phe bat dau thoat mot lnong carbon dioxide nen khoi boc nhieu hon, khong gian lan toa mui banh nnong, mui hat rang dac trnng Trong lnong hat ca phe tiep tuc giam xuong Hinh 1.10: Hat ca phe a giai doan sau ngung tieng no lan mot CHtfONG TONG QUAN 1.3.10 Giai doan chuan bi no lan hai - nhiet khoang 225o C Hat ca phe tiep tuc thu nhiet va the tich cang na lan han, the tich co the tang tren 150% Cac phan ung hoa hoc van lien tuc xay hat ca phe Hat ca phe co nhieu thay doi va chuan bi bndc vao giai doan no lan hai Hinh 1.11: Hat ca phe a giai doan chuan bi no lan hai 1.3.11 Giai doan bat dau no lan hai - Nhiet khoang 225° C Luc tu hat ca phe tiet nhieu chat dau, bao phu ca hat ca phe, lam cho hat ca phe tra nen sang bong, va nhin co ve am ndt Mui tham cang luc cang tinh te, hap dan lan toa ca khong gian cua vung lo rang, lam ngat nhnng a xung quanh Hinh 1.12: Hat ca phe a giai doan bat dau no lan hai 1.3.12 Giai doan no lan hai - nhiet khoang 235o C Tieng no lan thu hai phat sinh tu su la be gay vat ly cua cac cau truc celllose hat ca phe Moi mot chung loai hat ca phe cua cac giong ca phe co cac cau truc khac nhau, cho nen tieng no lan thu hai nay, theo giong ca phe ma chung ta lang nghe co co am thanh, tan suat, cudng am, va am vuc khac 5.3.4 Chon bo dieu khien nhiet do(Temperature Controller) Dieu khien nhiet gin vai tro trung tam bo dieu khien nhiet cho cum gia nhiet No nhan tin hieu tn sensor nhiet, xu ly va xuat tin hieu dieu khien SSR( Role cong suat) Ta co the cai dat nhiet can thiet de dang va tien loi Voi nhiet dieu khien khong qua cao (khoang 240 oC) ta chon bo dieu khien nhiet bien cua hang AUTONICS series T3S Model T3S-P4SJ4C Hinh 5.9: Temperature Controller Model T3S-P4SJ4C Bang 5.4: Thong tin bo dieu khien nhiet Bang 5.5: Dac diem ky thuat cua Temperature Controller Model T3S-P4SJ4C Model Power supply T3S 100-24 0VAC 0/60 Hz Allowable volt age range Power consLnption Display method Display accuracy Betting method Betting accuracy Sensor input Input line resistance ON/OFF Proportion al ResetVR range Control output 9Dto 11DS4 ot rated v o It a g e 5VA Eegnent LEG Csiplay F * S ± 1% rdg ± digitH Digit al setting F * S ±1% Thermocouples : K(CA), J(IC) / RTC : PtIOOil Thermocouples • Max 100£2 RTD : Max 512 per a wire Fysteres s : F * S 0.5 to =0.2 % Fixed] Proportional band : F • S =3% Fixed, Period : 20sec fixed F • S =3% variable(revision of control deviat ion) * • Self — diagnosis Insulat ion resistance Dielectric strength Noise strength Vibra —tion Sho ck Mechanical M al function Mechanical Malfunct io nMechanical Electrical Relay life cycle temperature Ambient Storage temperature Ambient humidity Wei g ht Relay contact OLtput : 25DVAC A c ■ EER outpLt : 2VDC ± 3V 5DnA max Current output : 4-20mACCILoad 600S2 max.) Built-in burn out funct ion a Min 00 V (at 500VCC ) 300DVAC 50.''60Fl2 for minute ± 2kV the square wave noise (pulse width:1 ua) by the noise simulat or 0.75mm amplitude at frequency of 10 to 55Hz in each of X Y Z directions for hour 0.5mm amplitude at frequency of to 55Hz in each of X, Y, Z directions for 10 minutes 30Dm/s a (Approx 3DG) times at X Y Z direction 100m/s* (Approx 0G) times at X, Y, Z direct ion Mir 10.000.000 times Min 100,000 times(250VAC 3A resistive load ) — to 50^0 (at non-freezing status) — 25to 65ti(at non-freezing status)^ 35to B5%RH Approx 96g Sa ket noi dien Hinh 5.10: So ket noi dien cho bo dieu khien nhiet CHtfONG THIET KE MACH DIEN Ngo 1,2,3 dung ket noi cam bien Neu dung cam bien loai TC chi co day dung ngo va Neu loai RTD thi dung 1,2,3 Ngo 4,5,6 dung ket noi voi SSR(Relay cong suat) dieu khien cho dien tro dot nong Khi dieu khien cho Heating dung ngo 5,6.Khi dung cho Cooling thi dung ngo 4,6 Trong do: TC (Themocuple) : Can nhiet RTD : Dien tro phat hien nhiet 5.3.5 Chon cam bien nhiet Loai cam bien nhiet duoc chon su dung cung voi bo dieu khien nhiet la Thermocouple Voi nhiet dieu khien khoang 240 oC ta chon theo dai nhiet cua moi loai cam bien duoc la J(IC) co khoang nhiet la 199-399 oC Bang 5.6: Dai nhiet cua cac loai cam bien Hinh 5.11: Thermocouple loai T3S - J(IC) 5.3.6 Chon SSR(Solid State Relay) SSR la mot ro le cong suat dung cho dong dien xoay chieu co tac dung dong ngat dieu khien Heater thong qua tin hieu dieu khien tu bo dieu khien nhiet Ta chon duoc SSR Model SSR1-1230 tu catalog Hinh 5.12: Solid State Relay Model SSR1-1230 Bang 5.7: Thong tin SSR cua hangAUTONICS Bang 5.8: Dac diem ky thuat SSR Model SSR1-1230 - Input 4-30VDC input voltage Input voltage range 4-32 VDC Max input current 9mA(Zero cross} J3mA(Randorn turn-on} Pick-up voltage Drop-out voltage 4VDC 1VDC Turn-on time Zero cross 0.5 cycle of load source + 1ms Random turn-on Max J ms Turn-off time 0.5 cycle of load source + 1ms 24VAC input voltage Input voltage range (50.'60Hz> 19-30VACrms Max input current l2mArms(24VACrms) Pick-up voltage lOVACrms Drop-out voltage 4VACrms Turn-on time 1.5 cycle of load source + ms Turn-off time 1.5 cycle of load source + ms 90-240VAC input voltage Input voltage range {50.'60 Hz) 35-264VACrms Max input current 7mArrns(240VACrms) Pick-up voltage 35VACrms Drop-out voltage lOVACrms Turn-on time 1.5 cycle of load source + 1ms Turn-off time 1.5 cycle of load source + 1ms CHtfONG THIET KE MACH DIEN Ket noi dien cho SSR: Tin hieu dieu khien tu Temperature Controller dugc noi vao chan 3/A1+ va 4/A2- Mot day noi tiep voi tai va noi vao chan 1/T1 cua SSr Day thu cua nguon noi qua cau chi bao ve va noi vao chan 2/L1 Kfch thuoc SSR: Hinh 5.13: So ket noi dien cho SSR Model SSR1-1230 Hinh 5.14: Thong so kich thudc cua SSR Model SSR1-1230 5.4 Thiet ke mach dien 5.4.1 Mach dong ltfc SO DO MACH DONG WC 220V MCP K u thung rang Thung rang Khay lam ngu§i Quat hut Hmh 5.15: So mach dong luc Qu^t hut khaynguQi 5.4.2 Mach dieu khien SO DO MACH 9DIU KHIEN Hmh 5.16: So mack dieu khien CHtfONG THIET KE MACH DIEN 5.4.3 Nguyen tac hoat dong cua mach Budc : Dong MCP de cap dien cho mach Budc 2: An nut ON tren mach dieu khien, dong dien se duoc cap vao mach chmh Day la nut an dang thudng mo nen can dung cuon day K de tri trang thai hoat dong cua nut ON Buoc 2: Bat cac cong tac va de khoi dong va cai dat cac thong so can thiet cho ro le thdi gian va bo dieu khien nhiet Luc cuon day T va T5 co dien se kich hoat cac tiep diem thudng mo RT va K5 dong lai Voi loai ca phe, ngudi rang se co che cai dat thdi gian rang va nhiet rang hop ly Dien tro luc se duoc gia nhiet cac dong co van chua hoat dong Buoc 3: Dau tien de chuan bi cho qua trinh rang ngudi rang se bat quat hut M3 de hut phan bui va trau ca phe sot lai qua trinh cap ca phe vao may Khi nut ON3 duoc tac dong, den tin hieu D3 se sang Dong dien se duoc cap vao cuon day cong tac to T3 lam thay doi trang thai lam viec cua cac tiep diem tren cac cong tac to nay.Khi tiep diem K3 se tu trang thai thudng mo chuyen sang thudng dong lam cho dong co M3 hoat dong Cac dong co M1, M2, M4 se hoat dong tuong tu cac cong tac tuong ung duoc kich hoat Buoc 4: Tiep theo ta can khoi dong cho thung rang quay bang cach kich hoat nut nhan ON1 tren ban dieu khien Khi nut ON1 duoc bat dong co Ml se quay va den D1 se hoat dong Buoc 5: Sau ca phe rang xong se duoc chuyen qua khay lam nguoi De bat dau qua trinh ta nhan nut ON2 lam cho dong co M2 quay cung luc thi den D2 cung hoat dong Song hanh voi qua trinh ngudi rang can bat dong co M4 de quat hut tham gia vao qua trinh lam nguoi Buoc 6: Khi ket thuc qua trinh nao thi ta se tat cong tac tuong ung cua dong co Sau cung nhan nut OFF tren mach dieu khien va dong MCP lai may se ngung hoat dong CHUONG BAO TRi, BAO DUONG De may hoat dong on dinh can co che bao tri, bao duong hop ly nham dam bao kha nang van hanh cua may Can thay the nhnng chi tiet, nhnng bo phan gap su co hay hong hoc va phai kiem tra may truoc hoat dong de tranh nhnng sn co ki thuat Che bao tri, thay the bao gom: 6.1 Che boi trnn o bi Muc d^ch giam ma sat gina cac chi tiet lan, chong mon, tao dieu kien thoat nhiet tot, bao ve be mat cua chi tiet khong bi gi, set, giam tieng on Chon mo boi tron cho o co nhnng uu diem sau: Do o bi co vong che nen chon mo boi tron cho phu hop Lap kin khe ho cua cac chi tiet may quay va chi tiet may co dinh Loai mo boi tron phai thich hop cho o bi duoc xai lau dai 6.2 Lam sach thung rang va thung nguoi djnh ki Muc dmh de lam thong thoang lo thoat bui, lam sach khoang thung de dam bao chat luong ve sinh ca phe Tuy nhien viec lam sach thung rang lien quan den viec thao may, do nen ket hop voi cac lan thay the o bi, hoac sua chna 6.3 Ve sinh si lo loc bui Dinh ki lay bui si lo de tranh lam day bui, han che kha nang loc bui cua si lo 6.4 Kiem tra, thay the dien tru nhiet Dien tro nhiet co tuoi tho khong cao nen phai thay the dinh ky CHUONG7 KETLUAN 7.1 Danh gia va nhan xet - Theo danh gia chu quan thi em thay ve quy trinh cong nghe thi tuong doi hop ly, phu hop vai xuong san xuat vua va nho Cac chi tiet bo phan de che tao may rang tuong doi de kiem va re - Ve qua trinh rang : ca phe duoc rang deu va khong mat nhieu phan hoa hoc - Qua trinh lam nguoi : ca phe duoc lam nguoi nhanh chong nho quat hut va cac canh dao gan lien tren truc - He thong loc bui : si lo loc bui la mot cong nghe kha bien hien nay, vi the nen phan lan cac nha may xi nghiep thuong lap dat he thong nay.Vai he thong mot phan lan bui se duoc hut ve silo, giam bat van de gay o nhiem va than thien vai moi truong 7.2 Mot so diem can khac phuc - May rang phai duoc lam viec lien tuc thi hieu suat mai cao - Qua trinh tu dong hoa chua cao phu thuoc vao tay nghe cua tho - Su gia tang nhiet cua truc va cac o bi se lam tang ma sat, do se lam giam tuoi tho o bi 7.3 Ket luan - Vai viec nghien cuu de tai “Thiet ke may rang ca phe” cung vai su huang dan tan tinh cua thay Bui Trong Hieu da giup em hieu ro hon phan nao cong viec quy trinh thiet ke may cua mot nguoi ki su Chiec may rang hoan co the se giup ich rat nhieu cho cac nha may che bien hoac cac cong xuong nho hoac cho nhung nguoi muon tu minh tao loai ca phe rieng dac trung - Tuy nhien kien thuc han hep, kinh nghiem thuc te chua nhieu, cac cong thuc tinh toan chi tra o goc tai lieu tham khao ma chua kiem tra thuc te nen gap nhieu sai sot, em mong thay co dong gop va chi dan them de em bo sung vao nhung phan thieu xot ay - Em xin duoc gui loi cam on chan den Thay Bui Trong Hieu cung cac thay co khac bo mon va ban be da giup do, chi bao em rat nhieu qua trinh lam de em co the hoan luan van mot cach tot nhat ... XI-34,trang 23 5 ] ta co : tarn = ^ — p1(n — 2^ ) (0, 424 Rcosa — p1) —m (3 .22 ) Vai : ^ = n /2 x0 = 0 ,25 R = 0 ,25 .0 ,22 5=0,0563 [1, XI .23 , trang 23 3] z0 = 0, 625 Rtg p = 0, 625 .0 ,22 5 tg45 = 0,14 [1, XI .24 , trang... ngndi rang + Thanh phan hoa hoc cua ca phe bi thay doi nhieu qua trinh rang lau 2. 2 .2 Gia nhiet vdi thiet bj long cau Hmh 2. 2: Rang ca phe kieu long cau - Nguyen ly : Ca phe dugc cho vao long cau... arabica (Ca phe Arabica) - ca phe che, ca phe Blue Mountain Coffea canephora (Ca phe Robusta) - ca phe voi Coffea excelsa (Ca phe Liberia) - ca phe mit voi nhieu loai khac Chat luong hay dang cap