thiết kế nhà máy sản xuất cà phê nhân
TRANSCRIPT
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PHN I:........................................................................................................................... 2 LI M U. ................................................................................................................ 2 PHN II: ......................................................................................................................... 4 LP LUN KINH T K THUT............................................................................... 7 PHN III:...................................................................... Error! Bookmark not defined. TNG QUAN V NGUYN LIU............................. Error! Bookmark not defined. PHN IV:......................................................................................................................15 CHN V THUYT MINH QUY TRNH CNG NGH. .......................................15 A. Chn phng php ch bin.....................................................................................15 B. Qui trnh cng ngh sn xut c ph nhn bng phng php kh..........................16 C. Qui trnh cng ngh sn xut c ph rang xay .........................................................24 PHN V:.......................................................................................................................29 TNH CN BNG NGUYN LIU ...........................................................................29 5.1.Tnh hnh sn xut ca nh my..............................................................................29 5.2. Cn bng vt cht cho sn xut c ph nhn..........................................................29 5.3. Tnh cn bng vt cht cho sn xut c ph rang...................................................36 PHN VI:......................................................................................................................39 TNH CN BNG NHIT LNG. ..........................................................................39 6.1. Cn bng nhit lng cho qu trnh sn xut c ph nhn.....................................39 6.2. Cn bng nhit lng cho c ph rang xay ............................................................44 PHN VII: ....................................................................................................................49 TNH V CHN THIT B.........................................................................................49 A. Tnh v chn thit b cho dy chuyn c ph nhn. .................................................49 B. Tnh chn thit b dy chuyn sn xut c ph rang ................................................66 PHN VIII: ...................................................................................................................74 TNH T CHC V TNH XY DNG...................................................................74 I. Tnh t chc ...............................................................................................................74 II. Tnh xy dng...........................................................................................................78 PHN IX:......................................................................................................................87 TNH HI - NC - IN. ........................................................................................87 A. Tnh hi ....................................................................................................................87 B. Tnh nc..................................................................................................................88 C. Tnh in...................................................................................................................91 PHN X:.......................................................................................................................99 TNH KINH T. ...........................................................................................................99 A. Tnh cho xy dng....................................................................................................99 B. Tnh cho trang thit b nh my..............................................................................101 PHN XI:....................................................................................................................106 AN TON LAO NG V V SINH CNG NGHIP. ........................................106 PHN XII:. .................................................................................................................109 KT LUN.................................................................................................................109 TI LIU THAM KHO...........................................................................................110
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PHN I:
LI NI U C ph l mt c sn ca cc nc vng nhit i, l sn phm c bun bn
nhiu trn th gii, i vi nc ta c ph cng chim mt phn quan trng trong
cc mt hng xut khu c gi tr. Hn na, do mt hng c ph , ang v s tng
cng pht trin nhiu l mt c sn qu gi ca vng nhit i. Vic tiu th c
ph trn th gii cng ngy cng tng, nht l Chu u, tp qun ung c ph
gn lin vi phong tc x hi v mc sinh hot vt cht. Mt hng c ph trong
nhng nm qua mang li li ch to ln ng gp mt tm quan trng trong s
nghip xy dng t nc.
Nc ta c iu kin thin nhin tt pht trin loi cy cao cp ny, nhiu
vng t rt thch hp trng c ph nh cc cao nguyn: Gia Lai, Kon Tum,
Daklak, Di Linh.
Do tp qun ung c ph c t lu i nn i vi nhiu ngi c ph tr thnh
thc ung thng nht, iu ny c l do hng v c bit ca c ph v tc dng
ch yu ca n.
C ph l mt loi thc ung kch thch thn kinh, gy hot ng minh mn cho
tr c v thng qua s kch ng h thn kinh, tng cng s hot ng ca cc b
my khc trong c th nh tr tim, xc tin s tun hon ca mu, nng cao sinh
lc chng mt mi cho c th ngi. Trong c ph hot cht ch yu l cafein, hm
lng ca n trong c ph t 1-3%, cafein l mt cht c v vy ung nhiu c ph
s sinh ra to bn, ung qu nhiu lm thn kinh qu kch thch b gy ri lon sau
c th dn ti suy nhc. Tuy nhin, c ph vn l thc ung hp dn i vi
nhiu ngi v nhiu la tui trn th gii bi l mt tch c ph ngon th c y
hng v c bit khin ngi ta thch th mt cch kh t. Vi nhng phng tin
v iu kin trang thit b hin nay ngi ta c th tch c nhiu cht thm c
trong c ph rang. V th, c ph l ung a chung v c nh gi cao.
Trn th gii hin nay c rt nhiu nc trng c ph, trong 4 nc c din
tch trng c ph ln nht l Brazil c khong 3 triu ha sn lng t 1056000 tn,
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chim khong 25% sn lng c ph trn th gii (trn th gii 5244000 tn),
Colombia hin c trn 1 triu ha, sn lng hng nm khong 750000 tn,
Innxia v Mxic c din tch trn di 1 triu ha.
Vit Nam trong nhng nm gn y tng nhanh din tch canh tc v sn
lng thu hoch c ph. Din tch nm 1989-1990 t 123000 ha v sn lng t
90000 tn. n nm 1998 t 350000 ha v sn lng t 400000 tn.
Mc d gi c c ph trn th trng gn y c nhiu bin ng nhng thu
nhp cao v nhanh chng nn thu ht nhiu c quan t nhn v h nng dn u
t vo ngnh sn xut c ph. Ngoi ra, p ng nhu cu ca ngi tiu dng
trong nc v xut khu, vng Ty Nguyn rng ln t ai kh hu thch hp cho
vic pht trin c ph. Trong nhng nm gn nht nc ta s c hng vn tn c ph
xut khu hng nm v l mt mt hng m c th gii u a thch.
Cng vi vic pht trin trng c ph th k thut ch bin i hi ngy cng
cao. Khu ch bin c nh hng ln n phm cht c ph v tc ng mnh n
sn xut c ph. Hin nay, chng ta c nhiu c s ch bin c ph nhn sng xut
khu v ch bin c ph bt, c ph ha tan, song qui m cn nh cha tp trung.
Nhng vi k hoch pht trin c ph trong nhng nm ti, cng tc ch bin nht
nh s t c nhng nh cao ca k thut ch bin hin i trn th gii.
Nhng thc t nc ta c rt t nh my ch bin c ph t cht lng cao m
ch yu l cc phn xng sn xut nh ca t nhn vi thit b lc hu, th s,
nng sut thp, cht lng khng cao.
Mt hng xut khu l c ph nhn ca chng ta cn km cht lng, b p gi
lm gim mt phn thu nhp. Hn na, do c ph nhn km cht lng nn cc sn
phm ca nhng qu trnh ch bin tip theo t c ph nhn ca chng ta cht lng
cng khng cao. Cho nn yu cu cn thit l phi xy dng mt nh my sn xut
c ph c tnh quy m ln l cn thit.
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PHN II:
LP LUN KINH T K THUT. 2.1.Tnh kh thi.
t nc ta ang trn ng cng nghip ha v hin i ha t nc cng vi
s pht trin vt bc ca nhiu ngnh kinh t, i sng tinh thn v vt cht ca
ngi Vit Nam v th gii ni chung ngy cng nng cao v nhu cu thng thc
cc sn phm c ch bin t c ph tng ln. Bn cnh , sn
v din tch trng c ph khng ngng tng ln, th trng xut khu rng ln. V
vy, cn phi Thit k xy dng mt nh my ch bin c ph nhn c phn xng
ph sn xut c ph rang xaynhm p ng nhu cu trong v ngoi nc. 2.2. a im.
Vic chn a im xy dng phn xng ng vai tr quan trng. V tr ca
nh my phi m bo cho nh my hot ng tt trong thi gian sn xut cng nh
p ng cc yu cu cng ngh trang thit b ca phng php m ta la chn
ch bin.
Nh my c xy dng tho cc iu kin: gn ngun nguyn liu, gn sng h
tn dng ngun nc, gn mng li in quc gia, cc iu kin kh hu: nhit
, m, hng gi thch hp
Daklak l mt Tnh c din tch trng c ph ln nht nc ta li c v tr a l
tng i thun li cho vic xy dng mt nh my v pha ng gip Khnh Ha
pha Bc gip vi Gia Lai, pha Nam gip vi Lm ng, nn rt thun li cho giao
thng i li vi cc Tnh ln cn do rt thun li cho vic vn chuyn nguyn
liu v tiu th sn phm.
Cn c vo nhng iu kin trn, ti quyt nh t nh my sn xut c ph
nhn c phn xng ph sn xut c ph rang xay ti Tnh Daklak. Nh my nm
st quc l 14 cch Thnh Ph Ban M Thut v quc l 13 khong 10 km v pha
ng. nhit v m trung bnh hng nm 23,30C v 82%. Hng gi chnh l
hng ng Bc.
2.3. Ngun nguyn liu.
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Daklak l mt Tnh c nhiu huyn trng c ph nh: MaDrak, Krngbng,
Krng N, CJut, Dakmin, ChMnga, Ea Sup, Krng Eana, KrngPach. l
nhng huyn c th cung cp ngun c ph cho nh my. Ngoi ra, ta c th vn
chuyn ngun nguyn liu c ph t cc Tnh khc nh: Lm ng, Gia Lai, Kon
Tum Do vy, vic chn a im t nh ti Tnh aklak s lm gim c chi
ph vn chuyn, m bo cht lng ca nguyn liu trc khi a vo sn xut.
2.4. ng giao thng.
Nh my a im ny rt thun tin cho vic giao thng.
+ ng b: Nh my nm st quc l 14, gn quc l 13, 19 cho nn thun
li cho vic nhp nguyn liu v phn phi sn phm.
+ ng thy: Nh my cch cng Nha Trang khong 150 Km cho nn c
th s dng cng ny phn phi sn phm trong v ngoi nc.
+ ng st: Nh my c th dng t vn chuyn sn phm v ga Nha
Trang, c th ng Container a sn phm i khp mi ni.
2.5. Nng sut.
Nhu cu c ph ca ngi dn ngy cng tng p ng lng c ph tiu th
trong nc v xut khu, cn phi xy dng nh my ch bin c ph c nng sut
cao m bo cht lng ng thi ph hp vi sn lng c ph ca a phng.
Hn na, M -Vit Nam k hip nh thng mi m ra con ng mua bn v trao
i hng ha v ng thi cng l mt th trng ln m ta cn khai thc trao i
cc mt hng trong c ph chim u th. Do , vic xy dng nh my sn xut
c ph nhn bng phng php kh vi nng sut 60 tn c ph qu/ca v phn
xng sn xut ph: c ph rang xay nng sut 1600 kg sn phm/ca l mt yu cu
cn thit phi xy dng.
2.6. Ngun cung cp nng lng.
+ in: Nh my s dng ngun in trn mng li quc gia ng dy 500
KV c h th xung 220/380 V. m bo s hot ng ca nh my c
lin tc, nh my chun b mt my pht in d phng.
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+ Nc: Ngun nc ca nh my c bm t ging khoan sau c qua
h thng x l v a vo sn xut.
+ Nhin liu: Nhin liu dng cho nh my bao gm: Du FO dng t l
rang c ph v xng dng cho xe t ca nh my.
2.7. Ngun nhn lc.
Trong qu trnh sn xut, ngun nhn lc c ngha rt quan trng bao gm: lc
lng cng nhn, cn b k thut v k s. i ng lnh o v cn b k thut c
th tip nhn t cc trng i hc hoc Trung hc chuyn nghip ti Min Trung
v Ty Nguyn. Cng nhn c th tuyn chn trc tip t lc lng lao ng trong
Tnh.
2.8. Th trng tiu th.
Mc d nh my ch bin c ph nm Ty Nguyn khng thun li nh cc
vng khc nhng do nm gn nhiu tuyn ng quc l nn vic phn phi sn
phm tng i thun li. Hn na, cht lng cc sn phm c ph Ty Nguyn
cao nn c th trng trong v ngoi nc a thch.
2.9. Hp tc ha, lin hp ha.
Vic hp tc ha gia cc nh my sn xut c ph ti Daklak vi cc nh my
cc Tnh khc s thun li cho vic u t trang thit b, my mc, pht trin nng
cp, ci tin k thut ca nh my ng thi qua s hp tc ny s to iu kin cho
vic s dng chung nhng cng trnh giao thng vn ti, cung cp in, nc
Ngoi ra, lin hp ha cn c tc dng nng cao hiu qu kinh t, nng cao hiu
qu s dng nguyn liu, h gi thnh sn phm.
2.10. X l cht thi.
Nc thi ra trong qu trnh sn xut khng t yu cu thi trc tip ra mi
trng do vy cn c x l, nc thi sinh hot, v sinh nh my c a vo
h thng cng rnh trong nh my n b x l nc trc khi thi ra ngoi mi
trng. Cc cht thi rn nn x l bng cch o h chn trnh gy nhim cho
ngi dn, cn cht thi dng v tru th s dng lm nhin liu.
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PHN III:
TNG QUAN V NGUYN LIU c tnh thc vt ca c ph.
Cc loi c ph u thuc ging coffea, gm gn 70 loi khc nhau, ch c 10 loi
ng ch v gi tr trng trt. Trn th gii hin nay ngi ta thng trng cc
loi sau:
+Ging Arabica.
+Ging Robusta.
+Ging Chari.
Cc ging ny u c thi gian thu hoch khc nhau nn c th b sung thi v
cho vic trng v thu hoch cc ging chnh.
3.1. C ph Arabica: thng gi l c ph ch.
y l loi trng nhiu nht trn th gii. Ngun gc ca ging ny l cao
nguyn Etipia vng nhit i ng Chu Phi.
c tnh:
Cy c ph Arabica cao t 3-5 m, trong iu kin t ai thun li c th cao
n 7 m, c thn hoc nhiu thn, l hnh trng hoc hnh li mc, qu thng
hnh trng c khi hnh cu, khi qu chn c mu ti, mt s ging khi chn c
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n Tt ngip Ngnh Cng Ngh Thc Phm L Th Thu Hiu - Lp 01H2B
mu vng ng knh qu 10-15 mm. S lng qu 800-1200 qu/kg, thi gian
nui qu t 6-7 thng. Trong iu kin thi tit kh hu min Bc, c ph Arabica
chn r vo thng 12 v thng 1. Ty Nguyn c ph chn sm hn 2-3 thng so
vi min Bc, khi qu chn nu b ma d nt v rng. Trong 1 qu c 2 nhn, mt
s t qu c 3 nhn. Nhn c v la mu bc bm cng vo nhn. Ngoi v la l v
tru cng, ngoi cng l v tht. T 5-7 kg qu s thu c 1kg nhn c ph sng.
Mu ht xm xanh, xanh lc, xanh nht, ty theo cch ch bin. Lng cafein c
trong nhn khong 1-3% ty theo ging. Nng sut 400-500 kg/1hecta.
T l thnh phm/nguyn liu khong 14-20%.
3.2. C ph Robusta: thng gi l c ph vi.
Ngun gc khu vc sng Cngg min ni vng thp xch o v nhit i Ty
Chu Phi.
c tnh:
Robusta cao t 5-7 m qu hnh trng hoc hnh trn, qu chn c mu thm.
V qu cng v dai hn c ph Arabica. T 5-6 kg qu s thu c 1kg c ph
nhn. Qu chn t thng 2 n thng 4 min Bc, Ty nguyn chn sm hn t
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thng 12 n thng 2. c bit loi c ph Robusta khng ra hoa kt qu ti cc mt
c ca cnh. Nhn hnh hi trn, to ngang v la mu nh nu bc. Mu sc ca
nhn xm xanh, xanh bc vng m g .ty thuc chng v phng php ch bin
lng cafein c khong 1,5- 3%.
Nng sut ln hn c ph Arabica, 500-600 kg/1ha. Tuy loi c ph ny hng
thm t nhng kh nng khng su bnh loi ny rt tt.
3.3. C ph Chari: thng gi l c ph mt.
Ngun gc x Ubangui Chari thuc bin h gn sa mc Xahara, loi ny c
a vo Vit Nam 1905.
c tnh:
Chari cy ln cao 6- 15 m l hnh trng hoc li mc, gn l ni nhiu mt
di, qu hnh trng num hi li v to. Qu chn cng 1 lc vi t hoa mi, cho
nn trn cng mt t cnh c th c ng thi qu chn, qu xanh, n hoa, hoa n
v n qu, l iu bt li trong thu hoch. Qu thng chn vo thng 5 n
thng 7.
Hoa ca c 3 loi c ph trn u n c chm, mu trng v hong thm ngt.
Nng sut: thng 500-600 kg/1ha.
Tt 1200-1400 kg/1ha.
T l thnh phm/nguyn liu: 10-15%.
y l mt loi c ph chu c hn, t kn t, t chu su bnh.
3.4. Thnh phn ha hc ca c ph.
3.4.1. Cu to thnh phn ca c ph.
Qu c ph gm c nhng phn sau: lp v qu, lp nht, lp v tru, lp v
la, nhn. 5
1.V qu 4
2.Lp tht v tht. 3
3.V tru. 2
4.V la. 1
5.Nhn.
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Lp v qu: l lp v ngoi, mm, ngoi b c mu , v c ph ch mm hn
c ph vi v c ph mt.
Di lp v mng l lp v tht, v tht c ph ch mm cha nhiu cht ngt,
d xay xt hn.
Ht c ph sau khi loi cc cht nhn v phi kh gi l c ph thc. V tru ca
c ph ch mng v d dp v hn c ph vi v c ph mt.
St nhn c ph cn mt v mng, mm gi l v la, chng c mu sc v c
tnh khc nhau ty theo loi c ph. V la c ph ch c mu trng bc rt mng v
d bong ra khi ht trong qu trnh ch bin. V la c ph vi mu nu nht, v la
c ph mt mu vng nht bm st vo nhn c ph.
Trong cng l nhn c ph, lp t bo phn ngoi ca nhn cng c nhng t bo
nh, trong c cha nhng cht du. Pha trong c nhng t bo ln v mm hn.
Mt qu c ph thng c 1, 2 hoc 3 nhn, thng thng th ch 2 nhn.
Bng 1: T l cc thnh phn ca qu.
Thnh phn Arabica (%) Robusta (%)
- V qu
- V nht
- V tru
- Nhn v v la
43 - 45
20 - 23
6 - 7,5
26 -30
41- 42
21- 22
6 - 8
26 - 29
3.4.2.Thnh phn ha hc ca cc phn cu to qu c ph.
3.4.2.1.Thnh phn ha hc ca v qu.
V qu c mu khi chn, l cht antoxian trong c vt ca ancaloit, tanin,
cafein v cc loi enzim. Trong v qu c khong 21,5-30% cht kh.
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Bng 3.2: Thnh phn ha hc ca v qu ( tnh theo % trong 1 g):
Thnh phn ha hc C ph Arabica (%). C ph Robusta (%).
- Protein 9,2 - 11,2 9,17
- Cht bo 1,73 2,00
- Xenlulo 13,16 27,65
- Tro 3,22 3,33
- Hp cht khng c Nit 66,16 57,15
- Cht ng - -
- Tanin - 14,42
- Pectin - 4,07
- Cafein
0,58 0,25
3.4.2.2.Thnh phn ha hc ca lp nht.
Pha di lp v qu l lp nht, n gm nhng t bo mm, khng c cafein,
tanin, c nhiu ng v pectin.
Bng 3.3: Thnh phn ha hc ca v nht:
Thnh phn ha hc C ph Arabica (%). C ph Robusta (%).
- Pectin 33,0 38,7
- ng kh 30,0 46,8
- ng khng kh 20,0 - - Xenlulo v tro 17,0 -
pH ca lp nht ty theo chn ca qu thng t: 5,6-5,7 i lc ln ti 6,4 Trong lp nht c bit c men pectinaza phn gii pectin trong qu trnh ln men.
3.4.2.3. Thnh phn ha hc ca v tru. Gm c xenlulo l ch yu, trong v tru c mt t cafein, khong 0,4% do t nhn khuch tn ra lc ln men hoc lc phi kh.
3.4.2.4. Thnh phn ha hc ca nhn.
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Bng 3.4. Thnh phn ha hc ca nhn c ph.
Thnh phn ha hc Tnh bng g/100g Tnh bng mg/100g - Nc 8-12
- Cht du 4-18
- m 1,8-2,5
- Protein 9-16
- Cafein 1(Arabica), 2 (Robusta)
- Clorogenic axit 2
- Trigonelline 1
- Tanin 2
- Cafetanic axit 8-9
- Cafeic axit 1
- Pentozan 5
- Tinh bt 5-23
- Dextrin 0,85
- Saccaro 5-10
-Xenlulo 10-20
-Hemixenlulo 20
- Lignin 4
- Tro 2,5-4,5
- Canxi 85-100
- Photphat 130-165
-St 3-10
- Natri 4
- Mangan 1-45
- Rb,Cu, F Vt
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Cu to ca c ph nhn chu nh hng bi chng c ph, chn ca qu, iu kin canh tc, iu kin ch bin v bo qun nhng thc t cha c nghin cu no
thit lp mi quan h vi thnh phn ha hc ca nhn c ph. C ph nhn dng thng phm gm c: nc, cht khong, lipit, protit, gluxit. Ngoi ra, cn c nhng cht m ta thng gp trong thc vt l nhng axit hu c
ch yu l axit clorogenic v cc cht ancaloit. Trn th gii cng nh trong nc ta
c nhiu nghin cu v phn tch thnh phn ha hc ca nhn c ph.
Ngoi ra, trong nhn c ph cn c mt lng ng k Vitamin, cc cht bay hi
v cu t ca mi thm.
Hin nay, ngi ta tm ra c ti hn 70 cht thm hn hp li thnh mi thm
c bit ca c ph. Trong c ph ch yu l Vitamin nhm B nh: B1, B2, B6v
cc loi axit hu c l tin cc loi Vitamin.
Mt s cc yu t nh hng n cht lng c ph.
+ nh hng ca loi t trng c ph:
t trng c ph c nh hng rt ln n mi v v mu sc ca c ph. Nu c
ph trng trn t bazan th cy tt, khe, sn lng cao, phm cht c ph tt cn
c mt hng v m , mi v thm ngon hn cc loi c ph trng trn cc loi
t khc.
+ nh hng ca ch chm sc k thut:
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Ch chm sc k thut trong thi gian trng c ph rt quan trng, ngi trng
c ph quyt nh cht lng c ph. Cc bin php chm sc k thut gm c:
- T gc cy c ph.
- nh nhnh to hnh cy.
- Phn bn ng k v ng s lng cn thit.
- S lng v cy bng mt cn thit cho tng loi c ph.
- Phng tr su bnh hi c ph.
Chm sc cy tt s c nh hng rt ln n sn lng c ph.
+ nh hng ca cao:
cao vng t trng cng nh hng n cht lng ca c ph. C ph trng
trn cao th c hng v c bit v xp hng cao hn c ph trng v tr thp.
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PHN IV:
CHN V THUYT MINH DY CHUYN CNG NGH A- Chn phng php ch bin c ph. Trong k thut ch bin c ph nhn c hai phng php chnh:
+ Phng php ch bin t.
+ Phng php ch bin kh.
- Phng php ch bin t: Phng php ny gm hai cng on chnh:
Cng on xt ti v phi sy: Loi b lp v qu v lp v nht, phi sy
n m nht nh.
Cng on xt v nh bng: loi b lp v tru v lp v la to thnh c
ph nhn bn thnh phm.
- Phng php ch bin kh: Qu trnh ch bin n gin nhng ph thuc vo
thi tit trnh ph thuc ngi ta s dng my sy. Phng php ny thng p
dng cho nhng vng c kh hu nhiu nng, ma t. Cng on chnh ca phng
php l sau khi phi hoc sy c ph n m nht nh ta dng my xt kh
loi b cc lp v bao bc nhn, khng thng qua cng on ch bin thnh c ph
thc.
S d ta chn phng php ch bin kh v y l mt phng php ch bin n
gin d lm, t tn nng lng, v sinh khng thi nhiu cht thi nh hng n cu
c sng ca ngi dn. y l mt phng php mang tnh th cng nhng n rt
ph hp vi a im t nh my l mt ni nng nhiu ma t v ng thi cng
tn dng c ngun nhn lc em li ngun thu kh n nh cho ngi dn vng
.
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B- Dy chuyn cng ngh sn xut c ph nhn theo phng php kh. 4.1. Dy chuyn cng ngh:
Sng phn loi
Nguyn liu (c ph qu)
Thu nhn v bo qun nguyn liu
Phi sy
C ph qu kh
Tch tp cht
Xay xt kh (b v tru)
nh bng (b v la)
Phn loi theo kch thc
P- loi theo trng lng
P-loi theo mu sc
Phi trn, cn, ng bao
Nhp kho
Bo qun
V tru, tm vht nh
Tm v ht nh C ph thc
hoc qu kh
C ph tm
Phn loi Ch bin ring
V tru
Ht >6,3mm Ht >5,6mm
Ht >5mm
P- loi theo trng lng P- loi theo trng lng
P-loi theo mu sc
P-loi theo mu sc
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4.2.Thuyt minh dy chuyn cng ngh.
4.2.1. Nguyn liu.
Nguyn liu l cc loi c ph qu c thu hoch, loi c ph chnh c
trng nc ta l Robusta chim khong 97%, Daklak trng gm 2 loi l
Arabica v Robusta.
4.2.2.Thu nhn v bo qun nguyn liu.
- Thu nhn nguyn liu:
C ph c thu hi bng phng php th cng, ch yu l thu hi bng tay.
Nng sut thu hi ph thuc vo nhiu yu t: u v, gia v, cui v, c ph non,
c ph gimc iu luyn ca ngi hi, phng tin trang b cho vic thu
hoch s nh hng trc tip n nng sut hi.
m bo phm cht tt, ng thi trnh lng ph v ri rng, h hng vic thu
hi cn t cc yu cu sau:
+ m bo ng chn ng u ca tri.
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+ Khng lm rng l, n hoa ang hnh thnh khng nh hng n ma thu
hoch nm sau.
+ Cn hi tng tri chn, khng hi tng chm hay sut ln tri cn xanh v tri
xanh cho nhn cho nhn nh, mu en khi phi kh v v ng.
+ Khng thu hi nhng qu cn xanh v lc cht d tr tp trung cha y
, kh ch bin do v la dnh st vo nhn. Ch ch hi nhng qu chn nng
cao cht lng sn phm.
+ Cn phn chia khu vc thu hi ph hp vi ma chn c ph.
+ Khng c lm tn thng n cy, qu c ph trong khi hi.
+ Gi v sinh trong qu trnh thu hi khng c ln cc tp cht nh: t, ct,
cnh, lvo trong nguyn liu.
- Vn chuyn v bo qun nguyn liu.
Sau khi thu hi xong cn nn vn chuyn ngay v ni ch bin khng nn
ng qu lu lm cho c ph bc nng v rt d ln men lm cho v chua. Ta c th
vn chuyn bng mi phng tin nh xe b, xe tTrong khi vn chuyn trnh
lm cho qu c ph b dp nt, trnh b ln tp cht, phn no b ln nn mang i
ch bin trc.
Nguyn liu sau thu hi nn ch bin cng nhanh cng tt, nu cha ch bin
th khng c cht thnh ng m phi c bo qun ni thong mt, c mi
che v tri thnh lp dy khong 30-40 cm trn nn sch, kh, 2-3 gi ta tin hnh
o trn mt ln. Thi gian bo qun cng ngn cng tt thng ko di khng qu
36 gi.
Mc ch ca qu trnh bo qun ny nhm iu phi nguyn liu trong qu
trnh sn xut. Trnh hin tng lng ph nhn lc, thit b ng thi cng m bo
c mu sc v hng v ca thnh phm.
4.2.3. Phi sy.
- Mc ch phi sy: Mc ch ca qu trnh ny l h thy phn ca c ph
xung 10-12% bo qun tt v thc hin cc qu trnh tip theo.
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+ Phi c ph: Nu iu kin thi tit cho php th phi c ph vn l k thut
c a chung hn v n n gin v t tn km. Hn na, tia cc tm ca nh
nng mt tri c th ty trng cht dip lc trong ht v lm gim mi ngi v mi
c trong c ph. Cn gim st qu trnh phi nng cn thn v a im phi v thi
tit c nh hng ln n qu trnh ny.
Sn phi nn c lm bng xi mng sch s khng b rn nt v b cch xa khu
vc cha v thi hoc cc cht thi t cc khu ch bin trnh b nhim khun.
Cn trnh phi c ph trn nn t v c ph d b nhim khun c trong t.
C ph c ri ro b t li cao khi phi ngoi tri v l mt trong nhng nguyn
nhn pht trin nm mc. trnh lm c ph t li cn phn ng kp thi v phi
che ph c ph khng cho tip xc vi nc ma. Ngay khi tri kh ro tr li cn
nhanh chng d b bt ph cho thong kh v tip tc phi. Nu c ph b che qu
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lu th ht s bt u ra m hi v s nhanh chng nhim nm v cc li th nm
s pht sinh.
Ban m, khi nhit xung quanh xung thp lm hi nc ngng t cn t bt
ln c ph trnh b t li.
Cc yu t nh hng n qu trnh phi:
- Nhit khng kh.
- m khng kh.
- Vn tc khng kh.
- Loi sn phi.
- Chiu dy lp nguyn liu v s ln co o trn sn.
+ Sy c ph bng my : Qun l c hiu qu nhit v m l vn mu
cht khi sy c ph. Sy c ph bng nhit qu ln hoc qu thp s khng cho
kt qu tt. Nhit sy l tng l t 45-550C. Ch cn tng ln 10C th s lm
gim m tng ng ca khng kh xung khong 5%. iu ny cho thy cn
thn trng nh th no trong khu khng ch nhit .
Thi gian sy di hay ngn ph thuc mt s cc yu t sau:
- Nhit khng kh nng v vn tc khng kh nng.
- m khng kh bn ngoi.
- m ban u ca nguyn liu.
Thng thng phi sy s b c ph qu ti trc ri mi c em sy kh
chnh thc.
4.2.4. Tch tp cht.
C ph qu kh sau khi phi sy thng c ln kim loi, cc tp cht nh nh
cnh, l, rm rc v cc v vn c ph cho nn trc khi a vo my xt kh,
nguyn liu phi c lm sch, ty theo ng u ca nguyn liu m cng
on tch cc tp cht ny l d dng hay kh khn, n gin hay phc tp. c bit
ch n cc tp cht kh lm sch loi chng ra, ng thi phi p dng
phng php c hiu qu nht v kinh t nht.
i vi phng php kh ngi ta thng dng sng rung tch cc tp cht.
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4.2.5. Xay xt kh.
C ph sau khi phi sy xong bn ngoi c lp v tru chim 25-35% trng
lng ht, thnh phn ch yu l xenlulo khng gp phn to nn cht lng ca
sn phm nn phi loi ra.
C ph thc sau khi xt kh ta c hn hp gm: c ph thc, tru, c ph
nhn, ht vn nt. Ty theo tnh cht v cng dng m cch gii quyt ca mi
thnh phm trong hn hp sau khi xt kh khng ging nhau.
- C ph thc a tr li my xt tch v ln na.
- C ph nhn l sn phm ch yu a i nh bng.
- Tru cha nhiu xenlulo v cht khong c th dng lm nhin liu.
- C ph vn nt c thnh phn tng t nh c ph nhn nn c th dng lm
sn xut c ph bt, c ph ha tan, c ph sa
+Yu cu ca qu trnh xt kh:
- Nhn nguyn vn.
- T l nt phi mc ti thiu.
- T l c ph cn v st li phi thp.
- Mc qut sch v tru phi cao.
4.2.6. nh bng.
Sau khi tch v tru, c ph ht cn c ln mt lp v la mng mu nh bc,
ch yu l xenlulo, v la cn c tch i bng cch nh bng. Qu trnh nh
bng cn gi l qu trnh bc v la. Do lp v la khng gp phn vo vic lm
nn cht lng ca sn phm nn ta tin hnh loi b n, ng thi vic bc v la
lm tng gi tr cm quan ca ht lm cho ht tr nn bng trn v hn ch c s
pht trin ca vi sinh vt.
Yu cu sau khi nh bng:
- Nhit c ph khng qu 550C.
- T l ht nt v
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4.2.7. Phn loi theo kch thc.
C ph sau khi ra khi my nh bng thng gi l c ph x bao gm tt c
cc loi tt, xu, nng, nh, v tru.cho nn ngi ta tin hnh phn c ph x
thnh cc c khc nhau theo kch thc.
Nguyn tc: l da vo s khc nhau v kch thc ca cc cu t c trong hn
hp. Kch thc l sng ty theo loi c ph v yu cu phn loi m chn loi c
kch thc cho ph hp.
Phn loi theo kch thc qua sng ngi ta thu c 3 loi ht c ph c kch
thc khc nhau: Ht >6,3mm chim 70%, ht >5,6mm chim 20%, ht >5mm
chim 10%. Ngoi ra, ngi ta cn phn ra c mt t c ph tm vi s lng
khng ng k.
Ngi ta s dng 2 loi sng chnh phn loi l sng trn v sng lc.
4.2.8. Phn loi theo khi lng ring.
+ Mc ch: sau khi phn loi theo kch thc ta c khi ht ng u theo
kch thc nhng khi ht khng ng nht v khi lng v cn c nhng ht lp,
ht b su bnh
+ Nguyn tc: da vo s khc nhau v trng lng ring ca ht ta s dng sc
gi phn loi chng ra, nhng ht c trng lng ring nh s bay ln.
+ Nhng yu t nh hng n qu trnh phn loi bng sc gi:
- Trng lng ring ca ht c ph c nh hng rt nhiu n hiu sut phn
loi bng sc gi. Nu cng mt sn phm m c trng lng ring khc nhau th
ht c trng lng nh s bay ln trc.
- Trng lng ring ca ht ph thuc vo m ca n, thng th t trng
ca ht c ph trung bnh l t 1,1-1,3.
- Hnh dng v kch thc ca ht c ph ca ht c nh hng trc tip n
cng tc phn loi theo trng lng. V vy, trc khi a sn phm vo phn loi
bng sc gi th yu cu cn thit phi phn loi bng kch thc trc.
4.2.9. Phn loi theo mu sc.
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+ Mc ch: Phn loi theo kch thc v trng lng ch loi b c tp cht,
tng ng u ca ht m thi. Khng lm tng gi tr cm quan v mu sc
ng u ca ht v vy cn phn loi theo mu sc lm tng cht lng ca sn
phm.
+ Nguyn tc: Thng phn loi da trn tiu chun nh nc hoc da trn
hp ng bun bn vi cc c quan hu quan hoc gia cc nc vi nhau v cng
tho mn c yu cu ca bn mua v bn sn xut.
4.2.10. Phi trn v ng bao.
- Phi trn cho c ph thnh phm c ng u v ng tiu chun ca
Nh Nc qui nh v theo yu cu xut khu. Thng s dng my phi trn c
gii, c ph sau cc cng on phn loi trn thu c 3loi c kch thc, khi
lng v mu sc khc nhau. u trn thnh 3 loi c ph: loi 1, loi 2v loi 3.
+ Loi 1: 80% ht > 6,3mm, 10% ht >5,6mm v 10% ht >5mm.
+ Loi 2: 10% ht > 6,3mm, 70% ht >5,6mm v 20% ht >5mm.
+ Loi 1: 10% ht > 6,3mm, 20% ht >5,6mm v 70% ht >5mm.
- ng gi theo yu cu s dng, c ph c ng gi thnh bao nh tin s
dng
4.2.11. Bo qun c ph nhn.
Cn bo qun c ph nhn tht tt gi cht lng c ph nhn chun b cho
cc cng on ch bin tip theo v bo m c ph khng b h hng do vi sinh vt
xm nhp ph hi trong thi gian vn chuyn.
Yu cu c ph bo qun trong kho:
- m ht 10-12%.
- Xp bao c ph trn nn lt bng vn trnh ht m, cch xa mi tng.
- Chuyn i v tr bao 2-3 tun mt ln.
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C- Dy chuyn cng ngh sn xut c ph rang xay. 4.1.Dy chuyn cng ngh.
Nguyn liu
X l, lm sch
Rang
Phn loi
Lm ngui
Phi trn
Nghin
Sng phn loi
C ph bt
Ht nh Ht va
Ht to
ng gi
Thnh phm
Ph phm
Ht ln Ht ln
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4.2. Thuyt minh dy chuyn cng ngh.
4.2.1. Nguyn liu.
C ph nhn l sn phm chnh ca nh my, mt phn sn phm ny c
dng lm nguyn liu cho qu trnh sn xut c ph rang xay.
4.2.2. X l v lm sch.
C ph nhn c a i sn xut khng qua bo qun th khng cn giai on
ny. Trong qu trnh sn xut c ph nhn c bo qun thi gian th phi x l v
lm sch.
+ Mc ch: trong qu trnh sn xut c ph nhn c bo qun mt thi gian
lu nn c ph nhn d b hp ph mi l c bit l mi mc nn phi x l trc
khi ch bin.
+ Phng php x l: C th x l bng nc hoc bng dung mi hu c.
- X l bng nc: c ph nhn sau khi bo qun (cht lng cn tt) ngm
c ph trong nc 5 pht lc ny nc s ngm vo ht ha tan mi mc, sau vt
ra ro, y l trng hp i vi mc nh.
- X l bng dung mi hu c: x l trong trng hp b mc nng dng
ru c nng 20% th tch. Thng th c ph sau khi x l, lm sch c a
ln bng chuyn nghing c g, c l li c ng knh 3 mm lm ro nguyn
liu trc khi a ln sng tch tp cht v phn loi.
4.2.3. Phn loi.
+ Mc ch: To cho khi ht c kch thc ng u, to iu kin cho qu
trnh rang c thun li.
+ Phng php: thng dng h thng sng tin hnh phn loi, da vo s
khc nhau v kch thc gia cc cu t trong hn hp c ph. Qu trnh phn loi
nguyn liu ta c 2 phn: phn lt sng gm cc phn t ht gy, v , phn khng
lt sng l cc ht nguyn. Khi ht c ph sau phn loi c tch em rang ring.
4.2.4. Rang.
Rang c ph l mt khu quan trng nht trong qu trnh ch bin c ph rang,
n quyt nh n hng v, cht lng, th hiu ca ngi s dng.
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+ Nhng bin i ha hc trong qu trnh rang:
- Giai on 1: Khi nhit rang < 500C giai on ny xut hin nhiu khi
trng bc ra ch yu l do hi nc hoc do hi ca dung mi hu c, th tch ht
khng b bin i, cui giai on ny ngi ta thy ngng sinh kh, y chnh l
thi im chuyn t giai on 1 sang giai on 2.
- Giai on 2: khi nhit t0 = 1500C, giai on ny thnh phn cc cht trong
ht bt u bin i, lc ny ta nghe c nhng ting n nh trong khi c ph rang
do c qu trnh tch kh trong ht, cc hp cht thm theo kh ra ngoi, th tch tng
ln, xut hin kh mu xanh thot ra ch yu l acrolein, cc cht gluxit, xenlulo b
caramen ha cho ht mu en m khng bng.
- Giai on 3: khi nhit t0 = 2200C, thi gian giai on ny ko di 10-15
pht, qu trnh sinh kh ngng li hoc yu i, ht chuyn sang mu en bng.
Trong khi rang thy phn hu nh bc hi ht, th tch c th tng ln 25-60%
nhn xp, b mt lng v d v, cht d bay hi bc i, mt phn cafein bc ra theo
mui c ph. Gluxit, xenlulo b caramen ha, protit phn hy, cht bo bin i,
mt s axit bc hi c to thnh c v ng v mi thm, trng lng gim 23-
28% ty theo mc rang.
Trong qu trnh rang giai on ny tng cht lng sn phm ngi ta cho
du thc vt, b, m g vo cui qu trnh rang cht bo ph ln b mt ht mt
lp mng gi c hng thm ca ht. Sau khi rang xong ht en bng bn trong
c mu cnh gin, mi thm nh.
+ K thut rang: C ph cho vo thit b rang, th tch khi ht < 20% th tch
thit b. Thng rang nhit 140-1800C sau nng nhit 200-2200C thi gian
40 pht/m. trong qu trnh rang mu sc bin i nh sau.
- Mu nht.
- Mu qu.
- Nu trung bnh.
- Nu hi m.
- Nu cnh gin.
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- Nu m.
- en thnh than.
Ty theo s thch ca ngi ung m rang. Nu rang mu nht th t thm, nc
nht, ung s hng mi g, nu rang chy c ph s ng, c mi kht nhng nc
m hn.
+ Nhn xt qu trnh rang: chng khong 1000C mu xanh ca ht c ph chuyn sang vng, 120-1300C ht c mu nu, 1500C ht bt u c mi chy,
1800C cc kh chy xut hin di hnh thc cc ln khi trng xanh, c CO v CO2 thot ra mu vng chuyn thnh nu, nhit cao hn th hng thm xut hin
nhiu hn, 2700C khi lng ht gim, ht en sm, 3000C ht chy.
4.2.5. Lm ngui.
Sau khi rang cc cht thm nhy cm bi nhit rt d bay hi lm gim phm
cht c rang. Do cn phi tin hnh lm ngui nhanh khc phc v hn ch
nhng im trn.
Khi lm ngui n nhit bnh thng ngi ta tin hnh phun ru c
c m 12% d bo qun, to cc phn ng este dn n c ph rang c mi
thm. V sau khi rang m ca nguyn liu l 0,5-1% rt d ht cc mi v l.
Ngi ta thng s dng bng ti lm ngui c ph rang.
4.2.6. Phi trn.
C ph ch bin n thun khng phi trn s khng p ng c phm cht
ngi ung a thch. Cho nn cn cn phi trn theo ng yu cu mong mun v
v v hng thm
4.2.7. Nghin c ph rang.
C ph c nghin mn s nng cao gi tr s dng v d dng cho vic
chun b pha ch.
C ph sau khi lm ngui v phi trn t yu cu cho vo my nghin. Trong
qu trnh nghin c ph b nng ln do ma st v p lc ca trc nghin, ngn
chn u ny ngi ta c th lm lnh bn trong trc nghin bng nc lnh. Qu
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trnh nghin c thc hin trong h thng thit b kn ngn chn s xm nhp
ca oxy trong khng kh.
Sau khi nghin ta thu c 3 loi bt nghin: bt to, bt va, bt nh. Bt to th
c a tr li my nghin, bt nh th lm ph phm, bt va th c em i
ng gi.
Bt sau khi nghin phi t cc yu cu sau:
- Bt mu nu c ln v bc sng ca c ph nhn, bt sau khi nghin lt qua
ray = 1,6mm l 90%, nhng c gi li trn ray = 0,05 mm ti thiu l 70%. i vi nhu cu tiu dng ca mi nc th tiu chun ny l khc nhau.
- m ca c ph bt l 4-5% .
4.2.7. Phn loi.
C ph sau khi nghin gm cc phn t ht mn v ht ln. V vy, phi cho hn
hp sau khi nghin qua sng phn loi tch cc phn t ht ln em i nghin li,
nhm m bo c ph bt c c kch thc theo yu cu.
Sau khi phn loi c ph c phi ch trc khi bo qun m bo c t
l cc thnh phn v cht lng, mi v, hng thm cng nh gi tr cm quan, t
l gia bt mn v bt th cho php, khu phi ch c b sung cht bo qun ko
di thi gian bo qun, vn chuyn v tiu th.
4.2.8. Bao gi, bo qun c ph bt.
C ph sau khi nghin nu tip xc vi khng kh v nh sng s nhanh chng
b mt mi v v hng thm, nu bo qun khng tt sau 2-3 tun xut hin mi
kht v v chua lm cho c ph gim cht lng.
khc phc tnh trng trn ngi ta phi tin hnh bao gi v bo qun c ph
theo ng ch qui nh, phi t chc thng xuyn lun chuyn d tr tn kho.
Mt khc phi tm cch ng gi bao b gi c cht thm ca n trong mt
thi gian lu, bao b phi c chn lc cn thn c kh nng chng m. Dng bao
b c 2 lp ng gi bn trong l lp chng m, bn ngoi l lp PE.
Thng thng trng lng ca mi gi l: 100g, 200g, 500g
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PHN V:
CN BNG NGUYN LIU. 5.1. Tnh hnh sn xut ca nh my:
5.1.1. Bng thu nhp nguyn liu ca nh my:
Daklak vo thng 8 thng ma v nguyn liu t nn cho nh my ngng sn
xut vo thi gian ny sa cha my mc, thit b.
Bng 5.1. Bng thu nhp nguyn liu ca nh my:
Thng 1 2 3 4 5 6 7 8 9 10 11 12
Arabica -
Robusta -
Chari -
5.2.2. Biu sn xut ca nh my:
Da vo bng thu nhp nguyn liu ca nh my v lng nguyn liu nhp
vo. Ta c th lp ra k hoch lm vic trong thng, s ca lm vic trong ngy. Mi
ngy lm vic 2 ca, mt ca lm vic 8 ting, ngy ch nht c ngh.
Thng 1 3 4 5 6 7 8 9 10 11 12
- S ngy lm vic 25 20 26 25 26 25 26 26 25 26 25
- S ca lm vic 50 40 52 50 52 50 52 52 50 52 50 - Tng s ngy sn xut trong nm: 275 ngy.
- Tng s ca sn xut trong nm: 550 ca.
- Tng s gi sn xut trong nm: 4400 gi.
- Nng sut ca nh my: 60 tn c ph qu/ca.
- Nng sut ca nh my tnh trong 1gi: 7500 kg/gi.
5.2. Cn bng nguyn liu cho sn xut c ph nhn.
n gin ta tnh ton cho 1000 kg nguyn liu c ph qu/gi cho loi c ph
Robusta.
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Bng 5.3. Bng t l hao ht sau ch bin qua cc cng on (%).
STT Cng on Hao ht (%)
1 - C ph qu ti, thu nhn v bo qun
2 - Phi hoc sy s b 0,5( khng k m )
3 - Sy chnh thc 1( khng k m )
4 - Tch tp cht 2
5 - Xt c ph thc 32
6 - nh bng c ph nhn 5
7
- Phn loi theo kch thc: + Ht >6,3mm. + Ht >5,6mm. + Ht >5mm.
0,5 0,5 0,5
8
- Phn loi theo khi lng: + Loi 1(ht >6,3mm). + Loi 2 (ht >5,6mm). + Loi 3 (ht >5mm).
1 1 1
9
- Phn loi theo mu sc: + Loi 1(ht >6,3mm). + Loi 2 (ht >5,6mm). + Loi 3 (ht >5mm).
1 1 1
10
- Phi trn, cn, ng bao: + Loi 1. + Loi 2. + Loi 3.
0,2 0,2 0,2
11
- Thnh phm: + Loi 1. + Loi 2. + Loi 3.
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5.2.1. Thu nhn v bo qun. - Lng nguyn liu: 1000 (kg/h). 5.2.2. Phi hoc sy s b.
Thng thng phi sy s b trc ri mi sy kh chnh thc sau. Qu trnh sy s b nhm loi b mt phn nc trn b mt ng thi gim bt m ca c ph t 52-60% cn 45%, nhm rt ngn thi gian sy giai on sy chnh thc v cht lng sn phm m bo hn.
- Lng nguyn liu vo: 1000 (kg/h). - T l hao ht: 0,5%. + Lng m tch ra trong qu trnh sy chnh thc c tnh theo cng thc:
2
211 w100
wwGG = (kg/h) [VIII-102].
Trong : - G : Lng m tch ra trong qu trnh sy (kg/h) . - G1: Lng nguyn liu trc khi sy (kg/h).
- w1; w2: m ca nguyn liu trc v sau sy. w1 = 55%; w2 = 45%.
G = 1000451004555 = 181,818 (kg/h).
+ Lng nguyn liu sau khi sy s b:
G2 = G1 G = 1000 181,818 = 818,182 (kg/h). + Lng hao ht tch ra trong qu trnh sy s b l: G2 = 818,1820,005 = 4,091 (kg/h).
5.2.3. Sy chnh thc:
Sy nhm h thy phn ca c ph xung cn 10-12%, chn 12%. - Lng nguyn liu vo: 818,182 4,091 = 814,091 (kg/h). - T l hao ht: 1%. - m ban u ca c ph qu: 45%. - m c ph sau sy l: 12%. + Lng m tch ra trong qu trnh sy chnh thc l:
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G = 814,091121001245 = 305,284 (kg/h).
+ Lng nguyn liu sau sy chnh thc l: G2 = G1 G = 814,091 305,284 = 508,807(kg/h). + Lng hao ht tch ra trong qu trnh sy chnh thc: G2 = 508,8070,01= 5,088 (kg/h).
5.2.4. Tch tp cht. - Lng nguyn liu vo: 508,807 5,088 = 503,719 (kg/h). - T l hao ht: 2%. - Lng nguyn liu hao ht : 503,7190,02= 10,074 (kg/h).
5.2.5. Xay xt c ph: - Lng nguyn liu vo: 503,719 10,074 = 493,645 (kg/h).
- T l hao ht: c ph qu kh v tru chim 25-35% trng lng ht ta chn 32%.
- Lng nguyn liu hao ht: 493,6450,32 = 157,966 (kg/h). 5.2.6. nh bng c ph.
- Lng nguyn liu vo: 493,645 157,966 = 335,679 (kg/h). - T l hao ht: 5%. - Lng nguyn liu hao ht: 335,6790,05 = 16,784 (kg/h). 5.2.7. Phn loi theo kch thc:
- Lng nguyn liu vo: 335,679 16,784 = 318,895 (kg/h). Gm cc loi ht: ht >6,3mm (70%), ht >5,6mm (20%), ht >5mm (10%). 1. Ht > 6,3mm (70%): + Lng ht > 6,3mm phn loi c: 318,8950,7 = 223,227 (kg/h). + Hao ht trong cng on ny l: 0,5%. + Lng nguyn liu hao ht: 0,005223,227 = 1,116 (kg/h). 2. Ht > 5,6mm (20%): + Lng ht > 5,6mm phn loi c: 318,8950,2 = 63,779 (kg/h). + Hao ht trong cng on ny l: 0,5%. + Lng nguyn liu hao ht: 0,00563,779 = 0,319 (kg/h). 3. Ht > 5mm (10%):
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+ Lng ht > 5mm phn loi c: 318,8950,1 = 31,890 (kg/h). + Hao ht trong cng on ny l: 0,5%. + Lng nguyn liu hao ht: 0,00531,890 = 0,159 (kg/h). 5.2.8. Phn loi theo trng lng ring:
1. Loi 1 (ht > 6,3mm): + Lng nguyn liu vo: 223,227 1,116 = 222,111 (kg/h). + T l hao ht: 1%. + Lng nguyn liu hao ht: 222,1110,01 = 2,221 (kg/h). 2. Loi 2 (ht > 5,6mm): + Lng nguyn liu vo: 63,779 0,319 = 63,460 (kg/h). + T l hao ht: 1%. + Lng nguyn liu hao ht: 0,0163,460 = 0,635 (kg/h). 3. Loi 3 (ht > 5mm): + Lng nguyn liu vo: 31,890 0,159 = 31,731 (kg/h). + T l hao ht: 1%. + Lng nguyn liu hao ht: 0,0131,731 = 0,317 (kg/h). 5.2.9. Phn loi theo mu sc:
1. Loi 1 (ht > 6,3mm): + Lng nguyn liu vo: 222,111 2,221 = 219,890 (kg/h). + T l hao ht: 1%. + Lng nguyn liu hao ht: 219,8900,01 = 2,199 (kg/h). 2. Loi 2 (ht > 5,6mm): + Lng nguyn liu vo: 63,460 0,635 = 62,825 (kg/h). + T l hao ht: 1%. + Lng nguyn liu hao ht: 0,0162,825 = 0,628 (kg/h). 3. Loi 3 (ht > 5mm): + Lng nguyn liu vo: 31,731 0,317 = 31,414 (kg/h). + T l hao ht: 1%. + Lng nguyn liu hao ht: 0,0131,414 = 0,314 (kg/h). 5.2.10. Phi trn, cn, ng bao:
- Ht loi 1 (ht > 6,3mm): 219,890 2,199 = 217,691 (kg/h).
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- Ht loi 2 (ht > 5,6mm): 62,825 0,628 = 62,197 (kg/h). - Ht loi 3 (ht > 5mm): 31,414 0,314 = 31,100 (kg/h). Ngi ta phi trn nh sau: 1. Loi 1 (80% ht loi 1+ 10% ht loi 2 + 10% ht loi 3 ): + Lng nguyn liu vo: 217,6910,8 + 62,1970,1 + 31,1000,1 = 183,483 (kg/h). + T l hao ht: 0,2%. + Lng nguyn liu hao ht: 183,4830,002 = 0,367 (kg/h). 2. Loi 2 (10% ht loi 1+70% ht loi 2 +20% ht loi 3): + Lng nguyn liu vo: 217,6910,1 + 62,1970,7 + 31,1000,2 = 71,527 (kg/h). + T l hao ht: 0,2%. + Lng nguyn liu hao ht: 71,5270,002 = 0,143 (kg/h). 3. Loi 3 (10% ht loi 1+20% ht loi 2 +70% ht loi 3): + Lng nguyn liu vo: 217,6910,1 + 62,1970,2 + 31,1000,7 = 55,979 (kg/h). + T l hao ht: 0,2%. + Lng nguyn liu hao ht: 55,979 0,002 = 0,112 (kg/h). 5.2.11. C ph nhn thnh phm:
+ Loi1: 183,483 0,367 = 183,116 (kg/h). + Loi 2: 71,527 0,143 = 71,384 (kg/h). + Loi 3: 55,979 0,112 = 55,867 (kg/h).
Vy tng ng vi 1000 kg nguyn liu c qu/gi (kg/h) s sn xut c: 183,116 + 71,384 + 55,867 = 310,367 (kg/h) c ph nhn. - T l gia nguyn liu v thnh phm l:
A = 367,310
1000 = 3,222.
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Bng 5.4: T l hao ht v lng nguyn liu vo qua cc cng on ch bin
STT Cng on
Hao ht (%)
Lng nguyn liu vo tnh cho 1000 (kg/h).
Lng nguyn liu tnh theo nng sut nh my ( kg/h).
Lng hao ht tnh theo 1000 ( kg/h).
Lng hao ht tnh theo nng sut nh my (kg/h).
1 - C ph qu ti 1000 7500
2 - Sy s b 0,5 1000 7500 4,091 30,683
3 - Sy chnh thc 1 814,091 6105,683 5,088 38,160
4 - Tch tp cht 2 503,719 3777,893 10,074 75,555
5 - Xt c ph thc 32 493,645 3702,338 157,966 1184,745
6 - nh bng c ph nhn 5 335,679 2517,593 16,784 125,880
7
- Phn loi theo kch thc: + Ht >6,3mm. + Ht >5,6mm. + Ht >5mm
0,5 0,5 0,5
318,895 223,227 63,779 31,890
2391,713 1674,203 478,343 239,175
1,116 0,319 0,159
8,370 2,393 1,193
8
{ - Phn loi theo Trng lng: + Loi 1 (ht >6,3mm). + Loi 2 (ht >5,6mm). + Loi 3 (ht >5mm).
1 1 1
222,111 63,460 31,731
1665,833 475,950 237,983
2,221 0,635 0,317
16,658 4,763 2,378
9
- Phn loi theo mu sc: + Loi 1 (ht >6,3mm). + Loi 2 (ht >5,6mm). + Loi 3 (ht >5mm)..
1 1 1
219,890 62,825 31,414
1649,175 471,188 235,605
2,199 0,628 0,314
16,493 4,710 2,355
10
- Phi trn, cn, ng bao:
+ Loi 1. + Loi 2. + Loi 3.
0,2 0,2 0,2
183,483 71,527 55,979
1376,123 536,453 419,843
0,367 0,143 0,112
2,753 1,073 0,840
11
- Thnh phm: + Loi 1. + Loi 2. + Loi 3.
183,116 71,384 55,867
1373,370 535,380
419,003
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5.3. Cn bng nguyn liu cho c ph rang xay:
Phn xng sn xut ph c ph rang xay l 1600(kg sn phm/ca). Vy nng
sut trung bnh l 1600 8 = 200 ( kg/h).
Bng 5.5. T l hao ht qua cc cng on.
STT - Cng on - Hao ht (%)
1
- Nguyn liu c ph nhn
2
- X l, phn loi, lm sch nguyn liu 1,5
3
- Rang c ph nhn 24
4
- Lm ngui Tng 3 ( k c m)
5
- Phi trn 0,5
6
- Xay c ph 0,5
7
- Phn loi bng sng 1,5 ( c ph phm)
8
- ng gi 0,2
9
- Thnh phm
5.3.1. Nguyn liu.
Ta s dng sn phm chnh ca nh my l c ph nhn (ca 3 loi) lm nguyn
liu sn xut c ph rang xay phn xng sn xut ph.
n gin cho vic tnh ton ta tnh cho 100 kg nguyn liu/gi.
5.3.2. X l, phn loi, lm sch nguyn liu:
+ Lng nguyn liu vo: 100 (kg/h).
+ T l hao ht: 1,5%.
+ Lng nguyn liu hao ht: 1000,15 = 1,5 (kg/h). 5.3.3. Rang c ph nhn:
+ Lng nguyn liu vo: 100 1,5 = 98,500 (kg/h).
+ T l hao ht: 24 %.
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+ Lng nguyn liu hao ht: 98,5000,24 = 23,640 (kg/h). 5.3.4. Lm ngui c ph rang:
+ Lng nguyn liu vo: 98,500 23,640 = 74,860 (kg/h).
+ Do khi lng ht c phun dch ng c nng 2% lm ngui
nn nguyn liu tng khi lng ln 3%.
+ Lng nguyn liu tng: 74,8600,03 = 2,246 (kg/h). 5.3.5. Phi trn:
+ Lng nguyn liu vo: 74,860 + 2,246 = 77,106 (kg/h).
+ T l hao ht : 0,5%.
+ Lng nguyn liu hao ht: 77,1060,005 = 0,386 (kg/h). 5.3.6. Xay c ph:
+ Lng nguyn liu vo: 77,106 0,386 = 76,720 (kg/h).
+ T l hao ht: 0,5%. + Lng nguyn liu hao ht: 76,7200,005 = 0,384 (kg/h).
5.3.7. C ph bt:
+ Lng c ph bt thu c: 76,720 0,384 = 76,336 (kg/h).
5.3.8. Sng phn loi:
+ Lng nguyn liu vo: 76,336 (kg/h).
+ T l hao ht: 1,5%.
+ Lng nguyn liu hao ht: 76,3360,015 = 1,145 (kg/h). 5.3.9. ng gi:
+ Lng nguyn liu vo: 76,336 1,145 = 75,191 (kg/h).
+ T l hao ht: 0,2%.
+ Lng nguyn liu hao ht: 75,1910,002 = 0,150 (kg/h). 5.3.10. Thnh phm:
+ Lng thnh phm thu c: 75,191 0,150 = 75,041(kg/h).
+ T l gia nguyn liu v thnh phm l: 333,1041,75
100 ==A .
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+ Vy c 1,333 (kg) nguyn liu th s cho 1 (kg) c ph bt thnh phm.
- T h s t l tnh c ta tnh ngc li cn bng nguyn liu cho phn
xng sn xut ph c ph rang xay 1600 kg sn phm/ca.
Ta lp bng sau:
Bng 5.6 :T l hao ht v lng nguyn liu vo qua cc cng on ch bin.
STT
- Cng on - Hao
ht (%)
Lng
nguyn
liu vo
tnh cho
100
(kg/h).
Lng
nguyn
liu vo
tnh theo
nng sut
nh my
(kg/h).
Lng
hao ht
tnh
theo
100
(kg/h).
Lng
hao ht
tnh
theo
nng
sut nh
my
(kg/h).
1
- Nguyn liu c ph nhn 100 266,521
2
- X l, phn loi, lm sch 1,5 100 266,521 1,500 3,998
3
- Rang c ph nhn 24 98,500 262,522 23,640 63,005
4
- Lm ngui tng 3% 74,860 199,517 2,246 5,986
5
- Phi trn 0,5 77,106 205,503 0,386 1,029
6
- Xay c ph 0,5 76,720 204,474 0,384 1,023
7
- Phn loi bng sng 1,5 76,336 203,451 1,145 3,052
8
- ng gi 0,2 75,191 200,399 0,150 0,400
9
- Thnh phm 75,041 200
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PHN VI:
CN BNG NHIT LNG. 6.1. Cn bng nhit lng cho qu trnh sn xut c ph nhn.
C s ca qu trnh cn bng nhit.
Ch sy c nh hng rt ln n cht lng sn phm. Chng hn, ch tiu sinh hc, ho l, cu trc c hc, thnh phn ho hc .Phi m bo trong qu trnh sy. Do cn phi c mt ch sy thch hp m bo ht t b rn nt, ng thi gi c cc tnh cht v hng v, mu sc v cc phn c trong ht. Ta s dng sy thp, tc nhn sy l khng kh nng. Cc thng s ban u. + Nhit khng kh sy: t1 = 750C. + Nhit nguyn liu vo: to = 23,30C. + Nhit nguyn liu ra: t2 chn theo nhit im sng. + Nhit mi trng khng kh trc khi qua calorife: to= 23,30C. + m ca nguyn liu trc khi sy: 45%. + m ca nguyn liu sau khi sy: 12%.
+ 0: l m ban u ca khng kh trc khi vo calorife : 0 = 82%. + p sut kh quyn: P = 757 (mmHg).
6.1.1.Xc nh cc thng s ca khng kh. 1. Cc thng s trng thi ca khng kh:
Trng thi ca khng kh trc khi vo calorife vi iu kin kh hu Daklak. to = 23,30C; 0 = 82% . [V-100]. + p sut hi bo ho ca khng kh Pbh = 21,49 (mmHg). + Hm m ca khng kh c xc nh theo cng thc:
bh0
bh00 PP
P622,0x
= (kg/kgkkk) [V- 56].
0148,049,2182,0757
49,2182,0622,0x 0 == (kg/kgkkk).
+ Hm nhit ca khng kh m trc khi qua calorife: Io = to + (2493 + 1,97 to)xo [V-156]. Io = 23,3 + (2493 + 1,9723,3)0,0148 = 60,876 (kJ/ kg kkk).
2. Cc thng s ca khng kh khi qua calorife trc khi vo my sy:
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Hm m ca khng kh sau khi qua calorife khng thay i do khi qua calorife, khng kh ch thay i nhit nhng khng thay i hm m [V-166 ].
. x1 = xo = 0,0418 (kg/kgkkk). + Chn nhit ca khng kh sau khi ra khi calorife l: 750C Pbh1 = 0,393 (at) = 297,501 (mmHg) [IV-312]. + m tng i ca khng kh sau khi qua calorife:
1bh1
11 P)x622,0(
Px+
= (%).
059,0501,297)0148,0622,0(
7570148,01 =+
= = 5,9% . + Hm nhit ca khng kh sau khi qua calorife: I1 = t1 + (2493 + 1,97 t1) x1 (kJ/kgkkk). I1 = 75 + (2493 + 1,9775) 0,0148 = 114,083 (kJ/kgkkk).
3. Xc nh nhit im sng:
+ Mc ch:
Khi tnh ton v sy cn phi bit nhit im sng ts v l gii hn lm
ngui khng kh m. Bit c ts khi chn nhit cui ca ca qu trnh sy ta
khng ly gn im ts trnh hin tng ngng t hi nc trn b mt vt liu.
+ Phng php xc nh nhit im sng:
Khng kh m c trng thi ban u l im A(xo; t ), t im A theo ng x
= const h xung ng = 1 ti im B, nhit ts s qua giao im B [V-160].
Ta c im A(0,0148 ; 23,3), xc nh c nhit ts th hnh [16.3].
[VI-160]. Ta c ts = 210C.
4. Thng s ca khng kh sau sy:
+ Da vo ts = 210C ta chn nhit khng kh sau sy l: t2 = 330C
Tra bng [IV-317] ta c Pbh2 = 37,7 mmHg.
+ Hm nhit ca khng kh ra khi thit b (sy l thuyt):
I2 = I1 = 114,083 (kJ/kgkkk).
+ Hm m ca khng kh sau khi ra khi thit b sy:
Ta c : I2 = t2 + (2493+1,97 t2) x2
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Suy ra: 0317,03397,12493
33083,114t97,12493
tIx2
222 =+
=+= (kg/kgkkk).
+ m tng i ca khng kh sau khi ra khi thit b sy:
2bh2
22 PP
P622,0x
= 2bh2
22 P)x622,0(
Px+
=
974,07,37)0317,0622,0(
7570317,0 =+= 2 = 97,4%.
5. Lng khng kh kh tiu hao ring bc hi 1 kg m:
12
1xx
l = (kg/kg m). [V-170].
172,590148,00317,0
1l == (kg/kg m).
6. Tng lng khng kh kh cn thit cho qu trnh sy: L = lU (kgkkk/h). Trong : - U : l lng m bay hi trong qu trnh sy (kg/h).
U = =G 2
211 W100
WWG (kg/h).
- G1: Lng nguyn liu trc khi vo my sy tnh theo nng sut nh my: G1 = 6105,683 (kg/h). - w1: m ban u ca c ph l; 45%. - w2: m ca c ph sau sy l; 12%.
U = G = 6105,683121001245 = 2289,631(kg/h).
L = 59,1722289,631= 135482,046 (kgkkk/h). 6.1.2. Cn bng nhit cho qu trnh sy.
1. Lng nhit cn thit lm bay hi 1kg m:
o2
o1
xxII
q = ( kJ/kg m) [V-170].
Trong : - Io, I1: l hm nhit ca khng kh trc v sau khi qua calorife. - xo, x2: l hm m ca khng kh trc v sau khi sy.
343,31480148,00317,0
876,60083,114q == (kJ/kg m).
2. Tng nhit lng cn thit cho qu trnh bc m:
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731,7208543631,2289343,3148UqQ1 === (kJ/h). 3. Lng nhit cn cung cp un nng sn phm: Q2 = G1C1(ttb - t0) (kJ/h) [VI-43]. Trong : - G1: lng nguyn liu ban u a vo sy (kg/h). G1 = 6105,683 (kg/h). - C1: nhit dung ring ca sn phm sy (kJ/kg.0C).
100
uC)u100(CC 1n1ck1
+= (kJ/kg.0C). [IV-152]. Trong : - Cn: nhit dung ring ca nc, Cn= 4,18 (kJ/kg.0C). - Cck: nhit dung ring cht kh ca c ph. Cck= 0,37 ( kcal/ kg.0C) = 1,547 (kJ/kg.0C).
- C1 732,21004518,4)45100(547,1 =+= (kJ/kg.0C).
- ttb: nhit un nng cho php nguyn liu sy:
542
75332
ttt 21tb =+=+= 0C. - to: nhit ban u ca nguyn liu sy; to = 23,30C. Q2 = 6105,6832,732(54 - 23,3) = 512098,287( kJ/h). 4. Nhit lng tn tht trong qu trnh sy: Nu thit b sy khng c bo n bn ngoi th c th ly nhit lng tn tht bng 8-12% lng nhit dng sy l thuyt (Q1). Qtt = 0,08Q1 = 0,087208543,731 = 576683,499 ( kJ/h). 5. Nhit lng ca calorife cn cung cp: Qcal = Q1 + Q2 + Qtt = 7208543,731 + 512098,287 + 576683,499 = 8297325,517 ( kJ/h).
6.1.3. Cn bng nhit lng vo v ra khi thit b sy. 1. Nhit lng i vo my sy:
+ Nhit lng do khng kh mang vo: Q1v = LIo (kJ/h). Q1v = 135482,04660,876 = 8247605,032 ( kJ/h).
+ Nhit lng do nguyn liu sy mang vo: Q2v = G2Cv1t1 + U1Cnt1 (kJ/h). [V - 166]. Trong : - t1: nhit ca nguyn liu trc khi vo my sy; t1 = 23,30C.
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- Cvl: nhit dung ring ca c ph Cvl= C1 = 2,732 (kJ/kg.0C). - U1: lng m bc hi trong qu trnh sy U1 = U = 2289,631(kJ/h). Cn = 4,18 (kJ/kg.0C). G2 = 3777,893 (kg/h). Q2v = 3777,8932,73223,3 + 2289,63123,34,18. = 463480,367 (kJ/h).
+ Nhit lng do calorife cung cp: Q3v = Qcal = 8297325,517 ( kJ/h).
+ Tng nhit lng mang vo: Qv= Q1v + Q2v + Q3v = 8247605,032 + 463480,367 + 8297325,517 = 17008410,920 ( kJ/h). 2. Nhit lng ra khi my sy:
+ Nhit lng do khng kh mang ra: Q1r = LI2 (kJ/h) [V - 167]. = 135482,046114,083 = 15456198,250 (kJ/h).
+ Nhit lng do nguyn liu sy mang ra: Q2r = G2 Cvlt2 (kJ/h) [V - 167]. = 3777,8932,73233 = 340599,721 (kJ/h).
+ Nhit lng tn tht: Q3r = Q tt = 576683,499 ( kJ/h).
+ Tng nhit lng ra: Qr = Q1r + Q2r + Q3r = 15456198,250 + 340599,721 + 576683,499 = 16373441,470 ( kJ/h). 3. Sai s:
%73,30373,0920,17008410
470,16373441920,17008410Q
QQQ
v
rv ====
V Q = 3,73% < 5% nm trong sai s cho php nn chp nhn kt qu trn [VI-49].
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6.2. Cn bng nhit cho c ph rang xay. Ta s dng nhin liu t l du FO. Thnh phn c trong du FO nh sau: [X-83]. Thnh phn C H O S A(m) Tro n v (%) 85,2 11,5 0,5 0,5 2 0,1
6.2.1.Tnh nhit tr ca nhin liu.
1. Tnh nhit tr cao ca nhin liu: Qc= 33858C + 125400H - 10868(O - S) (kJ/kg) [VII - 29]. Qc= 3385885,2% + 12540011,5% - 10868(0,5% - 0,5%). Qc = 43268,016 (kJ/kg). 2. Tnh nhit tr thp ca nhin liu: Trong nhin liu lng ngoi thnh phn ca nc A cha trong nhin liu cn c nc do phn ng chy sinh ra. T phn ng chy hydro d dng thy rng c 1kg H2 chy ht cho ta 9 kg nc. Do , nu ly nhit n ca nc p sut kh tri r = 2500 (kJ/kg) th nhit tr thp ca nhin liu: Qt= Qc- 2500 (9H + A) (kJ/kg) [VII-30]. Qt = 43268,016 - 2500 (911,5% + 2%). Qt = 40630,516 ( kJ/kg).
6.2.2. Lng khng kh kh l thuyt t chy 1kg nhin liu: Lo=11,5C + 34,5H + 4,3(S-O) (kgkkk/kgnl) [XII - 28]. Lo= 11,585,2% + 34,511,5% + 4,3 (0,5%-0,5%) Lo= 13,766 (kgkkk/kgnl).
6.2.3. Lng khng kh thc t t chy 1 kg nhin liu: L = L0 (kg/kgnl) [VII -28].
Trong :l h s khng kh tha, c xc nh nh sau: ( ) ( )[ ]( ) ( )[ ]0kk0a00
kkanlnlbc
t-tCI-IxLtCTroAH9-1-IAH9-tCQ
+++++= [VII-29].
Trong : - Qc = 43268,016 (kJ/kg). - A, Tro- thnh phn nc v tro trong nhin liu. - b : Hiu sut ban u = 0,750,9; Chn b = 0,85 [VII-29]. - tnl: Nhit nhin liu; tnl = 23,30C. - Lo= 13,766 (kgkkk/kgnl). - x0 : hm m ca khng kh ng vi nhit t0 = 23,30C.
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x0 = 0,0148 (kg/kgkkk). - I0: Hm nhit ca khng kh ngoi tri; I0 = 60,876 (kJ/kgkkk). - Cnl: Nhit dung ring ca nhin liu. - Ck, tk: Nhit dung ring v nhit ca khi l. - Ia: Nhit dung ring ca hi nc nhit khi l. 1. Nhit dung ring ca nhin liu:
5,0t
t
nl
nl )d(
)32t59(886,11625
C++
= (J/kg.0C) [IV-153].
- tnl = 23,30C. - ttd : Khi lng ring tng i ca nhin liu 15,6
0C (so vi nc
cng nhit ); ttd = 0,925 [IV-329].
589,1834925,0
)323,2359(886,11625
C 5,0nl =++
= (J/kg.0C)
Cnl = 1,835 (kJ/kg.0C). 2. Tnh nhit lng ring ca hi nc nhit khi l: Ia = 2500 +1,842 tk (kJ/kg) [VII-52]. tk: nhit ca khi l; chn tk= 2400C. Ia= 2500 +1,842240 = 2942,080 (kJ/kg) 3. Nhit dung ring ca khi l: Ck (kJ/kg.0C). Tra bng 1.179 (IV-204) ta c : Ck=1,034(kJ/kg.0C).T y ta xc nh h s khng kh tha:
( ) ( )[ ]( ) ( )[ ]3,23-240034,1876,60-08,29420148,0766,13
240.034,1%1,0%2%5,11.9-1-08,2942.%2%5,11.9-3,23.835,185,0.016,43268+
++++= = 9,187. + Lng khng kh kh thc t t chy 1 kg nhin liu: L = L0 = 9,18713,766 = 126,468 (kgkkk/kgnl).
6.2.4.Thnh phn cc kh c trong khi: Thnh phn ca cc kh c trong khi l kh i vi nhin liu du FO: CO2, N2, SO2, O2 v H2O. Khi t chy 1 kg nhin liu, khi lng ca tng phn : + 127,3%2,8567,3C67,3G
2CO=== (kg/kg).
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+ 381,97766,13187,977,0L77,0G 0N2 === (kg/kg). + 922,25766,13)1-187,9(23,0L)1-(23,0G 0O2 === (kg/kg). + 01,0%5,02S2G
2SO=== (kg/kg).
+ 055,1%2%5,119AH9G OH2 =+=+= (kg/kg). 6.2.5. Cn bng nhit lng cho thit b rang:
1. Nhit lng vo. Gi B (kg/m) l lng nhin liu du FO cn thit rang mt m nguyn liu. a. Nhit lng do nhin liu mang vo: qnl = Cnl tnlB (kJ/m) [IX-268]. qnl = 1,83523,3B = 42,756B (kJ/m). b. Nhit lng do nguyn liu mang vo: Ta chn lng nguyn liu mang vo rang l G1v = 70 (kg/m). q1v = G1vC11 (kJ/m). Trong : - G1v = 70 (kg/m). - C1: Nhit dung ring ca c ph t0 = 23,30C; (kJ/kg.0C). - 1 = t0 = 23,30C: nhit ban u ca nguyn liu. Ta c: C1 = [0,121+(1- 0,12)0,37]4,18 = 1,863 (kJ/kg.0C). theo cng thc C = C1x1 + C2x2 [IV-152]. x1= w1 = 12%: m ban u ca nguyn liu. T ta c: q1v = 701,86323,3 = 3038,553 (kJ/m)..
c. Nhit lng do khng kh mang vo: qkk = L0 I0B (kJ/m). [IX-268]. qkk = 9,18713,76660,876B = 7698,888B (kJ/m). d. Nhit lng to ra khi t chy nhin liu: qt = BQt (kJ/m) [IX-268]. Trong : - Qt l nhit tr thp ca nhin liu. Qt = 40630,516 (kJ/kgnl). qt = 40630,516B (kJ/m). e. Tng nhit lng vo: Qv = q1v + qnl + qkk + qt .
Qv = 3038,553 + 42,756B + 7698,888B + 40630,516B (kJ/m).
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2. Nhit lng ra. a. Nhit lng do sn phm mang ra: qsp = GspCsptsp (kJ/m). Trong : - Gsp = G1v - w: lng nguyn liu sau khi sy (kg/m). - w : lng m tch ra trong qu trnh rang.
2
211 W100
WWGw
= [VIII-33].
Trong : - W1: m ban u ca nguyn liu; W1 = 12%. - W2: m ca nguyn liu sau khi rang; W2 = 1%.
778,7110011270w =
= (kg/m). Gsp = 70 - 7,778 = 62,222 (kg/m). - Csp: nhit dung ring ca sn phm: Csp =[ 0,011 + (1 - 0,1)0,37 ]4,18 = 1,434 (kJ/kg.0C) - tsp: nhit sn phm ra; tsp = 2200C. qsp= 62,2221,434220 = 19629,797 (kJ/m). b. Nhit do m mang ra: qar= wIh (kJ/m) [V-167]. Trong : - w = 7,778 (kg/m). - Ih: nhit lng ring ca hi nc t = 2200C. Theo bng 1.250 [IV-313], ta c: Ih = 2803 (kJ/kg). Do : qar = 7,7782803 = 21801,734 (kJ/m). c. Nhit do khi l mang ra:
B)CGCGCGCGCG(q2222222222 NNOOSOSOCOCOOHOHkl++++= (kJ/m).
Trong : ...C,C.....;G,G OHOHCOOH 2222 l khi lng v nhit dung ring ca cc cht
tng ng. Tra bng [1.143;IX-158161] ta c : - 184,418,4001,1C OH2 == (kJ/kg.0C). - 844,018,4202,0C
2CO== (kJ/kg.0C).
- 627,018,415,0C2SO
== (kJ/kg.0C). - 907,018,4217,0C
2O== (kJ/kg.0C).
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- 037,118,4248,0C2N
== (kJ/kg.0C). qkl=(1,0554,184+3,1270,844+0,010,627+26,0720,907+97,976 1,037) B.
qkl = 132,308B (kJ/m). d. Nhit lng tn tht do phn ng chy khng hon ton.
Ta c : qtt1 = (0,0050,115)QtB [IX-269]. Chn qtt1 = 0,09QtB = 0,0940630,516B = 3656,746B (kJ/m). e. Nhit tn tht ra mi trng:. +Chn qtt2 = 0,08qsp. qtt2 = 0,0819629,797 = 1570,384 (kJ/m). + Vy tng nhit lng ra : Qr = qsp + qar + qkl + qtt1 + qtt2 (kJ/m). Qr = 19629,797 + 21801,734 +132,308B + 3656,746B + 1570,384. + Theo nh lut bo ton nng lng th: Qv = Qr (kJ/m).
3038,553 + 42,756B + 7698,888B + 40630,516B = 19629,797 + 21801,734 + 132,308B +3656,746B +1570,384.
B = 0,896 (kg/m). Khi lng du FO cn dng trong 1 gi : 360,3
70521,262896,0 = (kg/h).
Khi lng du FO cn dng cho 1 ca l: 3,3608 = 26,880 (kg/ca).
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PHN VII:
TNH V CHN THIT B. A- Tnh v chn thit b cho dy chuyn sn xut c ph nhn. 7.1. Thit b sy.
7.1.1.Thit b sy thp: Gii thiu chung:
H thng sy thp (HTS) dng sy cc vt liu dng ht nh ng cc, la m, ng, c ph, thc.H thng sy thp c nng sut ln nn rt ph hp dng sy c ph trong nh my. + Chn 2 my sy thp. + Lng nguyn liu cn thit vo mi my sy:
Q = 2
683,6105 = 3052,842 (kg/h).
+ Chn h thng sy thp HT-02 [XIV], l h thng sy c ly hi nng sch bng qut ht nhit thng qua h thng trao i nhit ca l t. Dng nhit xuyn qua lp ht lm gim m ca ht trong qu trnh sy ( m ban u w1 = 45% n m cn t ti w2 = 12%). + Ngoi chc nng sy, thp sy HT cn c kh nng lm ngui s b ht c sy. Cu to:
01. L t: dng cp nhit cho my sy. - Nhin liu dng t l du FO. - C dn trao i nhit calorife. - ng dng nguyn l i lu to nhit cho bung t.
L t to nhit cung cp kh nng cho thp sy, nhit c truyn i qua dn trao i nhit sau c qut ht nhit a vo khoang sy.
02. Thp sy: - Khoang cha: l khoang cha ht trn khoang sy cung cp nguyn
liu cho khoang sy. - Khoang sy: l khoang cha ht cn sy, c cc vch l sch hng
nhit t so le, ht cn sy s to thnh nhng lp mng chy theo vch.
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03. C cu chuyn ht: iu khin tc dng ht chy u trong khoang sy.
04. Qut ht l loi ht li tm cao p. 05. Gu ti:
c t su di nn bn hng thp sy, trn u gu c gn mt van 2ng di y gu c thit k 2 ca np 2 bn. Nhim v chnh l dng np v chuyn c sau khi sy hoc o c trong qu trnh sy.
06. Vt ti. 2 vt ti c t di c cu chuyn ht ca my sy thp c nhim v vn chuyn ht sau khi sy qua gu ti.
c tnh k thut:
- Nng sut my: 4000 (kg/h). - Cng sut lp t (HP). Gu ti GT-150: 01.
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B truyn c kh: 01. Qut ht nhit: 03. Qut nhm l: 0,25.
- Cng sut ng c: 8,74 (Kw). - Kch thc my: DiRng Cao = 2000mm3000mm6000mm. 7.1.2. Tnh v chn Calorife: Calorife l mt b phn quan trng trong h thng sy, n cung cp nhit cho tc nhn sy, ta chn tc nhn sy l khng kh nng. Trong calorife hi nc bo ho i trong ng cung cp nhit gin tip cho khng kh i bn ngoi ng. 1. Chn kch thc ng truyn nhit: + ng truyn nhit lm bng ng, ng c gn. + ng knh ngoi: dn = 0,038 (m). + ng knh trong: dt = 0,035 (m).
+ Chiu dy ng: 0015,02
dd tn == (m). + Chiu di ng: H = 2,0 (m). + ng knh ngoi ca gn: D = 1,4dn = 1,40,038 = 0,053 (m). + Bc gn: tg = 0,01(m).
+ Chiu cao gn: 0075,02
038,0053,02
dDh n === (m)
+ S gn trn 1 ng: 20001,00,2
tgHm === (gn).
+ B dy gn: bg = 0,002 (m). + Bc ng: to = 0,056 (m).
+ Tng chiu di ca gn trn 1 ng: Lg= mbg = 2000,002 = 0,4(m).
+ Chiu di ca ng c gn: Lo = H - Lg = 2 - 0,4 = 1,6 (m).
+ Din tch xung quanh ca ng khng c gn: 191,06,1038,014,3LdF on1 === (m2).
+ Din tch vnh khn ca gn trn ng
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( ) ( ) 429,0038,0053,02002414,3dDm2
4F 222n
22 === (m2).
+ Din tch xung quanh phn ng c gn: 067,04,0053,014,3LDF g3 === (m2).
+ Din tch b ngoi ca ng: 687,0067,0429,0191,0FFFF 321n =++=++= (m2).
+ Din tch b mt trong ca ng: 220,0035,0214,3dHF tt === (m2). 2. Xc nh hiu s nhit trung bnh: + Nhit khng kh vo calorife: t1 = t1 = 23,30C. + Nhit khng kh ra khi calorife: t1c = t2 = 750C. + Nhit bo ho ca hi nc: t2 = t2c = 1200C. H s nhit trung bnh xc nh theo cng thc:
t
c
d
cdtb
tt
ln
ttt
= [IX-253].
Trong : - t: hiu s nhit u; t = 120 - 23,3 = 96,70C. - tc: h s nhit cui; tc = 120 - 75 = 450C. - : h s hiu chnh ph thuc vo s chuyn ng ca cc cht ti nhit v ph thuc vo cc thng s R v P:
535,0
3,231203,2375
tttt
P
03,2375
120120tttt
R
d2d1
d2c2
c2d2
c1d1
==
=
==
=
Tra th 1= [XI-8]. 586,67
457,96ln
457,961t tb == 0C.
3. H s cp nhit t thnh ng ra ngoi khng kh (1): Nhit trung bnh ca khng kh trong calorife: ttb = t1 - ttb = 120 67,586 = 52,4140C. Tra bng I.255 [IV-318] ng vi ttb= 52,4140C ta c:
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+ H s dn nhit: = 2,84710-2 (W/m.). + nht ng hc: = 18,19610-6 (m2/s). + Chun s Pran: Pr = 0,6965. Chn vn tc khng kh trong calorife: w = 8 (m/s).
Chun s Raynon : 570,439610196,1801,08twRe 6
g ==
= [XI-13].
Lu th chy ngang qua ng chm c gn, v vy trong trng hp ny phng trnh chun s Nuyxen c dng:
4,0n14,0
g54,0
PrRet
htdCNu
=
[IX-226].
Trong : - d: ng knh ngoi ca ng, (m); d = dn= 0,038 (m). - t: bc gn: t = tg = 0,01 (m). - h: chiu cao ca gn: h = 0,0075 (m). - Do ng thng hng nn: C = 0,116 ; n = 0,72. [IX-226].
( ) ( ) 334,216965,0570,439601,0
0075,001,0
038,0116,0Nu 4,072,014,054,0
=
=
.
+ H s cp nhit 1 : 738,60
01,0334,2110847,2
tNutNu
2
g1
g1 ====
(W/m2.0C) [IX-227].
4. H s cp nhit pha trong ng 2: + Chn vn tc hi nc i trong ng = 4 (m/s). + Hi nc bo ho: to = 1200C. Tra bng I.249 [IV-311] ta c: + H s dn nhit: = 68,610-2 (W/m2.). + nht ng hc: = 0,25210-6 (m2 /s). + Chun s: Pr = 1,47.
Chun s 10000556,55555510252,0
035,04dRe 6t >=
== .
Do lu th chy xoy trong ng nn chun s Nu c xc nh theo cng
thc: 25,0
t
43,08,0x Pr
PrPrRe021,0Nu
= [IX-220].
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x: H s hiu chnh tnh n nh hng ca t s gia chiu di ng v ng knh ng: 143,57
035,02
dH
t
== .
Tra bng 7.2 [IX-221] => 03,1x = ; i vi cht kh th 1PrPr
t
.
( ) ( ) ( ) 433,1006147,1556,55555503,1021,0Nu 25,043,08,0 == . 087,19726
035,0106,68433,1006
dNu 2
t2 ===
(W/m2.0C).
5. H s truyn nhit:
++
=21
111K (W/m2.0C) [IX-248].
Trong : - 1 = 60,738 (W/m2.0C). - 2 = 19726,087 (W/m2.0C). - : h s dn nhit ca ng, (W/m2.0C). Tra bng [1.123 IV -125] ta c = 385 (W/m2.0C). - = 0,0015 (m). 533,60
3850015,0
087,197261
738,601
1K =++
= (W/m2.0C).
6. Tnh lng hi nc dng: Lng nhit l thuyt cn cung cp cho calorife trong mt gi: + Lng nhit m calorife cung cp cho qu trnh sy: Qcal = Q1 = 7208543,731(kJ/h). + Chn hiu sut trao i nhit: = 85%. + Lng nhit thc t cn cung cp cho calorife trong mt gi:
684,84806390,85
17208543,73QQtt === (kJ/h).
Lng hi nc bo ho dng trong mt gi : r
QD tt=
Trong : - r: n nhit ho hi ca hi nc bo ho nhit 1200C. r = 2207 (kJ/kg) bng I.250 [IV-313].
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610,38422207
48480639,68D == (kg/h). Th tch hi nc cn dng: V = Dv. v: th tch ring ca hi 1200C; v = 0,893 (m3/h) bng I.250 [IV-313]. V = 3842,6100,893 = 3431,451 (m3/h). 7. Xc nh cu to calorife:
+ Tng b mt trao i nhit ca calorife: tb
tt
K6,3QF = (m
2) [VIII-123].
Trong : - Qtt: lng nhit thc t cung cp cho calorife; Qtt = 8480639,684 (kJ/h). - K: h s truyn nhit; K = 60,533 (W/m2.0C). - tb: h s nhit gia hai lu th; tb= 67,586 (0C).
586,67533,606,3684,8480639F = = 575,807 (m
2 ).
+ S ng trong calorife: 147,838687,0807,575
FFn0
=== (ng); chn 838 (ng).
Chn 2 calorife, s ng trong mi calorife l: 4192
838 = (ng).
Chn calorife c 20 hng, mi hng c 2195,2020419 == (ng).
+ Kch thc mi calorife: Chiu rng calorife: Rcal = (n0 -1) t0 + D + 2 (x + y).
Trong : - x: khong cch t mp gn n thnh mp calorife. Chn; x = 0,01(m). - y: chiu rng thnh calorife, chn; y = 0,003 (m). - t0: bc ng; t0 = 0,056 (m). - D = Dg: ng knh ngoi ca gn; D = 0,053 (m). - n0: s hng ca calorife; n0 = 28 Rcal= (20 -1)0,056 + 0,053 + 2 (0,01+0,003) Rcal =1,143 (m).
Chiu cao calorife: Hcal = H + 2a. Trong : - a: b dy mi tm chn; a = 0,1 (m). - H: chiu di ng; H = 2 (m).
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Hcal = 2 + 20,1= 2,2 (m). Chiu di ca calorife: Dcal = (n1-1) t0 + D + 2 (x + y).
Trong : - n1: s ng trong mi hng; n1 = 21. Dcal = (21-1)0,056 + 0,053 + 2 (0,01 + 0,003). Dcal = 1,199 (m).
7.1.3. Chn qut. vn chuyn khng kh c u theo cc ng dn trong thit b sy ta s dng qut y, qut y c t trc calorife a khng kh ngoi mi trng qua calorife vo thp sy. Mc ch ca vic chn qut l xc nh cng sut ca ng c, vi h thng sy ny ngi ta cho bit cng sut ca ng c nn ta khng cn tnh ton cc tr lc ca qut. S lng qut cn dng: 2 qut. 7.2. Sng tch tp cht. + Chn 2 sng tch tp cht.
+ Nng sut cn thit vo mi sng: Q = 2
893,3777 = 1888,947 (kg/h).
+Chn loi sng LS -1.
c tnh k thut: + Nng sut sng: 2000 (kg/h). + ng c in: 2 (Kw). + Kch thc sng: DiRng Cao = 1000mm2000mm1400mm.
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+ Tn s dao ng: 1250 (ln/pht). 7.3. My xt kh. + Chn 2 my xt kh.
+ Lng nguyn liu vo mi my: Q = 2
338,3702 = 1851,169 (kg/h).
Gii thiu chung: My xt v dng xt v tch lp v ca c ph qu kh. Thnh phm i ra t
nh my l c ph nhn x. Chn my xt kh MXV-1 [XIV]. Cu to: 01.Trc chnh my. 03. Ca np liu. 02. B phn x liu. 04. i trng iu chnh
05. Nm iu chnh mt dao 06. Qut thi tp 07. Khung my
c tnh k thut: + Nng sut my: 2000 (kg/h). +Vn tc trc quay: 120 (v/ph). + Cng sut ng c: 1,2 (Kw). + Kch thc my: DiRngCao = 1500mm7000mm1500mm.
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7.4. My nh bng. + Chn 2 my nh bng.
+ Lng nguyn liu vo mi my: Q = 2
593,2517 = 1258,797 (kg/h).
+ Chn my nh bng MB- 500 [XIV]. Gii thiu chung: My c s dng bc lp v la v nh bng ht c ph nhn nhm nng cao cht lng thnh phm sau ch bin. Cu to:
01. Motor 03. B phn x liu 02. B phn np liu 04. Qut thi tp
05. i trng iu chnh bng.
c tnh k thut: + Nng sut my: 1500 (kg/h). + Vn tc trc quay: 150 (v/ph). + Cng sut ng c: 1,5 (Kw). + Kch thc my: DiRngCao = 1000mm2000mm1400mm. 7.5. Phn loi theo kch thc.
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+ Chn 2 my phn loi theo kch thc.
+ Lng nguyn liu vo mi my: Q = 2
713,2391 = 1195,856 (kg/h).
+ Chn my phn loi theo kch thc KT-1 [XIV]. Gii thiu chung: Chc nng ca my ny dng phn loi kch thc ht c ph theo nhng kch thc khc nhau da trn cc kch thc tiu chun ca mt sng. Ngoi kh nng phn loi my ny cn tch c cc tp cht nh: bi, ht v, m
Cu to: 01.Chn . 03. Motor truyn ng trc chnh. 02. Mng np liu. 04. Khung sng. 05. Ca ra thnh phm.
c tnh k thut: - Nng sut my: 1500 (kg/h). - Kch thc sng: Di rngcao = 2000mm1500mm1400mm. - Cng sut ng c in: 0,6 (Kw). - S ln dao ng: 450 (ln/pht). 7.6. Phn loi theo trng lng. + Chn 2 my phn loi theo trng lng.
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