Mill Material Balance
C H A P TE TE R X I I
THE COMPUTER PROGRAM
The example of a calculation for a comprehensive mill material balance above was done manually with the use of an ordinary calculator. It’ll takes time to complete, say about 7 (seven) to 8 (eight) hours for a mill tandem excluding the time for composing its evaluation comments together with the conclusions and recommendations. With the computer program the result will be completed instantly and the user needs only to fill in the data. There were 3 (three) programs made with Lotus and / or Excel, each for the tandem of 4 (four), 5 (five) and 6 (six) mills respectively. Each program has 2 (two) versions of calculation: §
The Evaluation, and
§
The Projection
The evaluation program is used to evaluate the overall performance of the tandem and for each mill respectively, using its average daily analysis and data obtained during the milling season from the operation of a week period and a bi-weekly as well. While the projection program is used for the planning of an optimal performance of a tandem. Whereas the extractions for total Brix and at mill # 1 and the total sugar, the %pol and dry matter of the last mill bagasse could be determined based upon the tandem’s capability and the quality of cane milled. Beside the items described in the example above, the comprehensive mill material balance also determining no-void volume of bagasse exhausted by each mill. That is why the Projection Program can also be used to determine the mills setting for the next milling season, as well as the resetting or adjustment of the mills necessarily during the season. The program is provided with such relevant calculation including determination of the distances for the feeder rollers and the width of Donnelly chutes.
12.1
THE EVALUATION PROGRAM
The program consisting of 2 (two) sheets: §
Sheet-I is for the data inputs.
§
Sheet-II is the results of the material balance and its evaluation.
12.1.1
The Data Sheet (Inputs)
Let us use the same data for the example in Chapter IX. Fill in the data on Sheet-I (Evaluation Data), which are the blue letters or numbers in the red lined boxes and follow the instruction inst ruction provided on the sheet.
The Computer Program Program
XII-1
Mill Material Balance
M I LL
M A T E R I A L
B A L A N C E
IN PUT FOR EVALUATION (average or totalized of data achieved) A T TE TE N T I O N :
Ty Ty p e i n t h e d a t a ( b l u e l e t t e r s ) i n t h e r e d l i n e d s q u a r e b o x e s o n l y .
Sugar Factory M ill Tra Tra in
EXAMP LE 2 CC + 5 MILLS
Milling Season (year) Pe riod of 15 milling days, number number
1977 X
Period Period dates evaluated up to I .
Last date
M I L L R O L LE LE R S I N U S E (d (d i m e n s i o n i n m m )
M I L L N O : --------------->
I
II
III
IV
V
1, 0 52. 0 1, 0 50. 0 1, 0 48. 0
1, 073 . 0 1, 069 . 0 1, 066 . 8
1, 051. 0 1, 048. 0 1, 040. 0
1, 05 0. 0 1, 04 8. 0 1, 04 0. 0
1, 06 4. 0 1, 05 2. 0 1, 04 8. 0
2 5. 0 2 5. 0
25 . 0 25 . 0
15 . 0 15 . 0
1 5. 0 1 5. 0
1 5. 0 1 5. 0
delivery top
2 5. 0 1, 0 02. 0
25 . 0 1, 023 . 0
15 . 0 1, 021. 0
1 5. 0 1, 02 0. 0
1 5. 0 1, 03 4. 0
f eed d el elivery
1, 0 00. 0 99 9 98. 0
1, 019 . 0 1, 016 . 8
1, 018. 0 1, 010. 0
1, 01 8. 0 1, 01 0. 0
1, 02 2. 0 1, 01 8. 0
Le Le n g t h o f s h e ll A ct c t ua u a l roller rotation/hour De D el ive ry work op eni ng
L rph hd
2, 1 3 3 2 68 41 . 2 3
2 , 13 3 2 44 36.33
2,133 21 6 27.79
2, 133 1 91 26. 14
2 , 1 33 1 93 2 4 . 62
F e e d t o d e l iv e r y r a t io H y d r a u lic p r e s s u r e
i ph
2.20 1 80
2. 00 1 82
2. 0 0 18 2
2 . 00 2 06
2 . 00 2 10
Hy Hy d r a u lic r a m d i a . Tr Tr a ns mi s s i on f a ct o r
d r
3 30 86
3 30 86
33 0 86
3 30 86
3 30 86
M ill rolle r s h a f t d ia . M ill rolle r sh e l l l e n gt h
dp l
4 20 4, 2 2 0
4 20 4 , 22 0
42 0 4,220
4 20 4, 220
4 20 4 , 2 20
To T o p a ng l e To Top roller lift - on fe ed ope ni ng
a t tf
78 6.0 4.7
78 6. 0 4. 7
78 6. 0 4. 7
78 6. 0 4. 7
78 6. 0 4. 7
td
4.7
4. 7
4. 7
4. 7
4. 7
Ou Ou t s i d e d i a m e t e r ( D o) :
top feed delivery
Gr G r oo v e c o r r ec t i o n ( k ) :
top feed
Mea n d ia me te r (Dk ):
- o n d e l i v er y o p e n i ng II.
M I L L I N G
C a n e :
O P E R A T I O N
cr ushed, t otal
Q
4,351.0 TCD =
cr cr u sh i n g d ur a t i on po pol
jg pt
24.00 hours 10.32 %
br brix fi fiber Mi M ixed jui ce:
gr o s s
bt f Gnm
brix c or or re re ct ct io io n
bn m k nm nm
Im I m b ibi tion wate r, t otal A pplied on:
Gi b aga ss e 1
13.41 % 16.07 % can e 3,718.7 Tons =
843.1 Tons = 0 %
3 5, 1 28 ltr/hr =
7 6 . 96 % 8 5. 5. 47 47 % c a ne ne 77.62 % 1 2 0 . 5 8 % fibe r
19.38 % c a n e
0 % 0 % 100 % 1.60000 kg/dm3
Bx B x r a t i o j u i c e # 1 t o c a n e
1.30
1 1 1 . 0 1 % ----->
Last mill bagasse juice to fiber =
± 100%
R E S UL UL T S O F A N A L Y S I S ( a v e ra ra g e ) :
M I L L NO: ---------------> J uic e:
1 54 54 ,9 ,9 46 46 kg /h /hr = 11.40 Purity Purity =
ba ga ss e 4 A verage value value of fiber density density
IIII I .
Puri ty =
14.69 %, pol pol = 1.00308
ba ga ss e 2 ba ga ss e 3
b n 1/ bt =
1 81 . 29 TCH
brix
bn
po p ol
pn
The Computer Program Program
I
II
III
IV
V
u n it
17 . 4 6 14 . 0 5
12.48 9. 29
8. 9 0 6. 4 5
5 . 75 4 . 06
2 . 94 2 . 00
% %
XII-2
