Lynne Wong's PhD thesis

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Brix (refractometric) is the percentage by mass of soluble solid matter (sucrose and soluble non-sucrose) in solution as indicated by a sugar refractometer or as derived from the refractive index of a solution and reference to tables of equivalent percent sucrose and refractive indices. Brix-free water or “hydrated water” as referred to in South Africa, or “adsorption water” or “hygroscopic water” as in Australia, is defined as the water strongly adsorbed onto the cane fibre and, unavailable for dissolving the soluble components in sugar cane. It cannot be separated from the natural cane fibre by mechanical means, only at elevated temperatures, and it is assumed to be 25% on dry fibre. Cane crushing rate is the rate at which cane is crushed by the mills. Chemisorption is the chemical adsorption process in which the adsorbed molecules are attached by strong chemical bonding. Desorption – see adsorption. Dextran is a high molecular mass polysaccharide formed by the action of certain species of bacteria, mainly leuconostoc mesenteroides, on sucrose. Dry matter (in cane) is taken as the Brix and fibre in the cane. Equilibrium moisture content (EMC) is the moisture content attained when a hygroscopic material is kept in contact with air at constant temperature and humidity until equilibrium is reached. Extraction (pol) is the percentage of pol in cane which passes into mixed juice. Analogous definitions apply to sucrose extraction, Brix extraction and juice extraction. Extraneous matter in cane is all foreign matter (e.g. cane tops, dry and green leaves, soil, rocks, cane roots, etc) delivered with the cane. Some authors used the word “trash” as a collective term for all extraneous matter, or more frequently, as the dry leaves associated with cane stalks. In this study, the term “trash”, if used, will refer to the dry leaves associated with cane stalks. Fibre in cane is the dry water-insoluble component of cane. Natural fibre is that fibre with chemically bound (Brix-free) water present in its structure. Filter cake is the residue removed by filtration in the process of juice clarification. (xl)
Filterability of a raw sugar is measured by comparing the filtration rate of the sugar with that of a standard sucrose solution under specified conditions. It is expressed as a percentage of the filtration rate of the standard sugar. Imbibition is the process in which water or juice is applied to bagasse to enhance juice extraction at the mill tandem. Imbibition water is the water used in the imbibition process. Lime saccharate is obtained from a mixture of milk of lime and a sucrose solution in a certain proportion, and is used in cane juice clarification. Massecuite is the mixture of sugar crystals and mother liquor discharged from a vacuum pan. Massecuite are classified according to descending purity as A, B, etc or first, second, etc. Mill extraction is the percent mass of sucrose originally in the cane that has been extracted into the mixed juice. Mixed juice is the mixture of juices leaving the milling train or a cane diffuser for further processing. Molasses is the mother liquor of massecuite separated from the crystals by mechanical means. It is designated as for the massecuite from which it is extracted, e.g. A-molasses. Final molasses is molasses obtained from the final massecuite and from which no further sugar will be removed. Net isosteric heat of sorption (q st ), or the enthalpy of sorption is defined as the isosteric heat of sorption (Q st ) minus the heat of vaporisation of water at the system temperature. Non-pol is dry substance minus pol, and dry substance is the material remaining after drying a product to constant mass under such conditions that it does not suffer chemical change. Non-sucrose is analogous to non-pol, it is dry substance minus sucrose. Overall recovery is the percentage of the pol in cane that passes into sugar (see boiling house recovery). (xli)
Page 1 and 2: THE BRIX-FREE WATER CAPACITY AND SO
Page 3 and 4: dissolved and hydrated waters, and
Page 5 and 6: ACKNOWLEDGEMENTS I am particularly
Page 7 and 8: Page 1.5 THE DELETERIOUS EFFECTS OF
Page 9 and 10: Page 2.2 THE PHENOMENON OF BRIX-FRE
Page 11 and 12: Page 3.4.3.3 Cane tops 83 3.4.4 Cha
Page 13 and 14: 4.3.3 Temperature at which Brix-fre
Page 15 and 16: 4.6.1 Materials 143 4.6.1.1 Samples
Page 17 and 18: CHAPTER 6. PROPERTIES OF THE SORBED
Page 19 and 20: APPENDIX 3. CALCULATIONS LEADING TO
Page 21 and 22: LIST OF FIGURES Page Figure 1.1. Fi
Page 23 and 24: Figure 3.1. Glucose and fructose an
Page 25 and 26: Figure 5.11. Residual plots for the
Page 27 and 28: total adsorbed water (m) and the pr
Page 29 and 30: Table 2.18. Moisture content in sug
Page 31 and 32: Page Table 4.4. Results of the dete
Page 33 and 34: Page Table 4.24. Analysis of varian
Page 35 and 36: Page Table 5.13. Table 5.14. Equili
Page 37 and 38: Table 6.3. Heat of sorption of the
Page 39: GLOSSARY OF TERMS Absorption is the
Page 43 and 44: Sorption is the generic term used w
Page 45 and 46: LIST OF MAIN SYMBOLS Symbol Descrip
Page 47 and 48: s c s Slope of Caurie I isotherm pl
Page 49 and 50: number of 255, and cane land covere
Page 51 and 52: Nouvelle Mon In Trésor ustrie and
Page 53 and 54: Figure 1.3. Cane sampling by core s
Page 55 and 56: In Mauritius, most of the sugar fac
Page 57 and 58: are: cane tops, dry and green leave
Page 59 and 60: 1.4 TRENDS IN CANE QUALITY RECEIVED
Page 61 and 62: campaign was launched to encourage
Page 63 and 64: The level of extraneous matter in c
Page 65 and 66: In Australia (Cargill, 1976), cane
Page 67 and 68: The effect of soil on factory perfo
Page 69 and 70: leaves increased the level of impur
Page 71 and 72: • From 1976 to 1980, when the pro
Page 73 and 74: Clerget purity of molasses 40 Clerg
Page 75 and 76: CHAPTER 2. IMPACT OF EXTRANEOUS MAT
Page 77 and 78: Since the extrapolated purity of mo
Page 79 and 80: Figure 2.1. Jeffco cutter grinder.
Page 81 and 82: 2.1.4 Results The analytical result
Page 83 and 84: Table 2.3. Analytical results of re
Page 85 and 86: Table 2.5. Composition of dry trash
Page 87 and 88: Table 2.7. Predicted factory perfor
Page 89 and 90: Boiling house recovery 91.0 89.8 89
Page 91 and 92:
0 5 10 15 20 % EM in cane y = 0.572
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% EM in cane 0 5 10 15 20 0 -2 -4 -
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1 y = 0.020 (% D) R 2 = 1.00 = 0.03
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% EM in cane 0 5 10 15 20 0 -2 y =
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esulting in 0.015 unit sucrose loss
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2.2.1 Experimental procedure Cane m
Page 103 and 104:
filter paper, rejecting the first f
Page 105 and 106:
Table 2.9. Effect of increased addi
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Table 2.11. Effect of increased add
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Table 2.13. Effect of increased add
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various components such as stalk fi
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in the presence of dry leaves, if c
Page 115 and 116:
Table 2.17. Moisture content in sug
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CHAPTER 3. SEPARATION OF THE SUGAR
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Table 3.1. It can be seen that the
Page 121 and 122:
Table 3.2. Fibrous physical composi
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R 579 R 570 M 1557/70 M 1400/86 74
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loosen the fibre. The woody core is
Page 127 and 128:
agitate the mixture in the pot, and
Page 129 and 130:
Figure 3.7. Custom-built fibre-pith
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The extraction of fibres starting f
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pre-treatment in a Jeffco cutter-gr
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Figure 3.19. Stalk cake washed free
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not have many dry leaves attached t
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Table 3.5. Masses of cane samples a
Page 141 and 142:
Table 3.7. Masses of cane samples a
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Table 3.9. Masses of cane component
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3 57.6 126.3 23.7 97.2 31.1 53.8 11
Page 147 and 148:
Table 3.12. Material loss (%) from
Page 149 and 150:
3.5.3 Fibre/pith ratios in cane com
Page 151 and 152:
Table 3.15. Effect of extraneous ma
Page 153 and 154:
Snow (1974) investigated the season
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from Figure 2.9 that the change in
Page 157 and 158:
Table 3.18. Fibre % cane results by
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110
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(a). Dry leaf (b). Green leaf (c).
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dry fibre, or a factor, is used in
Page 165 and 166:
Steuerwald (1912) applied sucrose s
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solution/fibre ratio was lowered fr
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leave some residual moisture on the
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instead of 150 g of 10° Brix sucro
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Table 4.2. Determination of Brix-fr
Page 175 and 176:
Table 4.3. Comparison of Brix-free
Page 177 and 178:
Table 4.4. Results of the determina
Page 179 and 180:
In order to test for homogeneity of
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Table 4.7. Results of the repeat de
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The experiment was repeated with th
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e any residual moisture in the samp
Page 187 and 188:
By means of the same technique, Won
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was still hot. Since the filter was
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value determined could be corrected
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Qin and White’s finding was confi
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A sample size of 3.5 g with 75 g co
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Figure 4.4. Fibre samples drying in
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- One large fibre sample (rind) of
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Table 4.18. Brix-free water values/
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Table 4.20. Brix-free water values/
Page 205 and 206:
4.7.3 Statistical analysis It is es
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Table 4.23. Analysis of variance (B
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pointing out that at 52 weeks old,
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The crop of R 570 sampled in 2001 w
Page 213 and 214:
4.7.4. Estimated Brix-free water co
Page 215 and 216:
The main difference in the two sets
Page 217 and 218:
Table 4.27. Predicted Brix-free wat
Page 219 and 220:
4.8 SUMMARY AND CONCLUSIONS An anal
Page 221 and 222:
component parts, and verify the Bri
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3) Thermodynamic, water in equilibr
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Langmuir (1916, 1917, 1918) propose
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to determine the moisture sorption
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Table 5.1. Some commonly used isoth
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Lomauro et al. (1985) found that wi
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and on agricultural products such a
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Bruijn (1963) studied the mass incr
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After measuring the EMC of dry corn
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approached, that is, either by adso
Page 241 and 242:
Table 5.4. Water activity (a w ) of
Page 243 and 244:
5.6.3 Procedure to determine equili
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5.6.4 Results and discussion An exa
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Table 5.8. Equilibrium moisture con
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Table 5.10. Equilibrium moisture co
Page 251 and 252:
Table 5.12. Equilibrium moisture co
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30 o C 45 o C 55 o C 60 o C Water w
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m/m of 96% activity, a w (g/100g dr
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vaporisation generally decreases fr
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30 o C isotherm 45 o C isotherm 55
Page 261 and 262:
4 0 Stalk fibre 5 0 Stalk pith 5 0
Page 263 and 264:
5.6.4.4 Fitting of sorption models
Page 265 and 266:
Table 5.19. Parameters of the sorpt
Page 267 and 268:
Page 269 and 270:
Page 271 and 272:
Page 273 and 274:
Page 275 and 276:
Modified GAB Kuhn Iglesias - Chirif
Page 277 and 278:
Table 5.28. Classification of resid
Page 279 and 280:
Stalk fibre Stalk pith Rind fibre 4
Page 281 and 282:
5.6.4.5 Calculated EMC values of re
Page 283 and 284:
Table 5.30. Calculated equilibrium
Page 285 and 286:
m/m of 96% Table 5.32. Calculated e
Page 287 and 288:
Table 5.33. Parameters of the Hailw
Page 289 and 290:
CHAPTER 6. PROPERTIES OF THE SORBED
Page 291 and 292:
where m is the equilibrium moisture
Page 293 and 294:
Page 295 and 296:
Page 297 and 298:
6.2 THE NUMBER OF ADSORBED MONOLAYE
Page 299 and 300:
6.3 TOTAL SOLID SURFACE AREA AVAILA
Page 301 and 302:
Thus, for each cane component of ea
Page 303 and 304:
abscissa. For each moisture level (
Page 305 and 306:
Page 307 and 308:
A similar procedure was followed to
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10 0 Stalk fibre Stalk pith Rind fi
Page 311 and 312:
Moreover, if T β > T hm the proces
Page 313 and 314:
Table 6.5. Characteristic parameter
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Binding energy/kJ (kg mol) -1 2 0 0
Page 317 and 318:
6.8 CALCULATION OF BOUND WATER AND
Page 319 and 320:
The values of K 1 , K 2 and W were
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Table 6.7. Separation of the total
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Table 6.7. (Contd.) Sample 30 o C 4
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3 0 S talk fibre 4 0 Stalk pith 3 0
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3 0 Reconstituted cane at 30 o C 3
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when water is added to dry wood, wh
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It is evident that in some cases ma
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The number of adsorbed monolayers,
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Data in Tables 2.9 and 2.11 show th
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particular fibre is systematically
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Anon. (1985b). Laboratory manual fo
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Blanchi R.H. and A.G. Keller (1952)
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Day D.L. and G.L. Nelson (1965). De
Page 345 and 346:
Heyrovsky J. (1970). Determination
Page 347 and 348:
Kuhn I.J. (1964). A new theoretical
Page 349 and 350:
Madamba P.S., R.H. Driscoll and K.A
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Prinsen Geerligs, H.C. (1897). Stud
Page 353 and 354:
Sing K.S.W., D.H. Everett, R.A.W. H
Page 355 and 356:
Van der Pol C., C.M. Young and K. D
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Lynne Wong's PhD thesis

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