Download (4Mb) - USQ ePrints - University of Southern Queensland

More documents

Recommendations

Info

chronological age. Harvest will be timed according to the yield per length of row so as to manage the cost of harvesting. As mallees grow the proportions of their biomass in the form of wood, leaf, twig and bark varies (Peck et al, 2011). The biomass composition varies according to many factors other than mallee size, perhaps the most significant being the availability of soil moisture; with better access to moisture, mallees can sustain higher leaf areas. Mallees growing in dense blocks are typically observed to have small crowns at the top of the plant, whereas mallees in narrow belts with greater access to usable soil moisture will carry heavier crowns, sometimes extending almost to the ground. However across all species observed in the work of Peck et al (2011), the trends are that with increasing age or size, the proportion of wood increases, the proportions of leaf and twig both decline, and bark varies relatively little. There are differences between species and within species there are also differences between saplings, or previously unharvested mallees, and regenerating coppice. In saplings: • Wood varies between 10% and 30 % of biomass for 10 kg mallees to about 45% for mallees weighing 100 kg. The range observed in the smaller mallees is partly according to species. • Twig and leaf vary together and are very similar proportions of total biomass. In small mallees both fractions represent 30% to 40% of biomass, falling to 20% to 25% for large mallees. • Bark typically comprises between 5% to 10% of biomass for all mallee sizes, though in E. kochii ssp plenissima, the proportion of bark rises to 15% in large mallees at the expense of leaf and twig proportions. In regenerating coppice: • Wood varies between about 15% in all species for small coppice to 25% to 40% in 100kg coppice, with different species having different proportions in these larger mallees. • Leaf and twig again vary together, being about 40% each in small coppice, down to about 30% in large coppice. • Bark is again a small proportion, being about 5% of biomass and a little higher in large E. kochii ssp plenissima. The market requirements for biomass composition, the efficiency of harvesting, and the economics of biomass production all influence the composition of the biomass. At this stage, before market development has occurred, we can only define trends and directions of influence. Wood is likely to have the highest value as a fuel because it has low ash content (Peck et al 2011; Wu et al, 2011). It is also the biomass component most likely to have other market potential, such as charcoal production. It will be easier to separate wood chip from the rest of the biomass than it will be to subdivide the rest of the biomass into leaf, twig and bark. Leaf is likely to have next highest value as it contains the eucalyptus oil (2-3% of total fresh weight of leaf) and after distillation, the bulk of the material may represent a useful relatively low grade fuel source. This residue may contain undesirable levels of alkali metals and alkaline earth metals, and other problematic elements such as chlorine. Recent work has recorded reduced ash content after hydrodistillation (Wu et al, 2011) but steam distillation may produce different results. Twig will have value as a relatively low grade fuel source but often with less ash than the leaf and bark (Peck et al, 2011). 15
Bark has relatively high ash but as it is a small proportion it will presumably have only a modest impact on the value of leaf/twig residue with which it will be mixed. It would appear that harvesting bigger mallees will produce the most valuable biomass (highest wood proportion) and saplings (previously unharvested mallees) will produce a higher wood yield than coppice. There are modest differences between species, with E. loxophleba ssp lissophloia producing higher wood proportion biomass than E. polybractea and E. kochii ssp plenissima; however the yield of wood per kilometre of row or hectare per year may not be superior for E. loxophleba ssp lissophloia for all soil types or climatic conditions. E. loxophleba ssp lissophloia also produces a lower quality eucalyptus oil than the other two species. E. loxophleba ssp lissophloia also appears to produce the greatest wood proportion in large 100 kg mallee coppice (about 45%) compared to E. polybractea (about 35%) and E. kochii ssp plenissima (about 25%). Experience to date with the harvester indicates that for a given weight, large coppice are easier to harvest than large saplings. It may be that coppice rotations will be harvested on longer cycles than previously anticipated to improve harvester efficiency and to produce a better quality biomass product. In general it appears that choosing the most productive species for the environment, to produce the most wood per kilometre of row or hectare, and growing larger mallees to allow higher harvester efficiency will remain the best approach. However there will be a limit (as yet undefined) to the size of mallee that may be harvested with an over-the-row chipper harvester. Extending the harvest interval has an economic penalty because of the effect of discounting on the value of future revenue. Figure 1.5 Six year old E. loxophleba subsp. Lissophloia (Note growth suppression in internal row, which occurs at most sites with belt configurations wider than 2 rows) Sugar system All cane produced in Australia is mechanically harvested. The chopper-harvester, removes the top, cuts the cane stalk at ground level and chops it into billets 200 to 300 mm long. Extraneous matter, 16
Page 1 and 2: Sustainable Biomass Supply Chain fo
Page 3 and 4: Foreword This report provides an as
Page 5 and 6: include business development (new p
Page 7 and 8: Acknowledgments The authors would l
Page 9 and 10: 4.1 Product Options and Supply Chai
Page 11 and 12: Table 4.2 Assessment of current val
Page 13 and 14: Figure 3.4 Tracked rigid self-prope
Page 15 and 16: Executive Summary What the report i
Page 17 and 18: • Biomass production potential of
Page 19 and 20: • As the Industry expands, the mo
Page 21 and 22: Harvesting, transport and storage s
Page 23 and 24: Biomass processing, supply chain pl
Page 25 and 26: Key barriers to biomass industries
Page 27 and 28: Crop-Biomass Production Production
Page 29 and 30: Figure 1.1 The cropping and pasture
Page 31 and 32: Table 1.1 Mallee species used for p
Page 33 and 34: 1.1.4 Growth Cycle Mallee System Ma
Page 35 and 36: northern New South Wales (where it
Page 37: Almost 80% of the industry now cuts
Page 41 and 42: Carbon sinks Planting of mallees to
Page 43 and 44: Table 1.5(a) State Land area devote
Page 45 and 46: out the fluctuations in farm income
Page 47 and 48: Mallee system Most of the mallee bi
Page 49 and 50: inconclusive result may have been d
Page 51 and 52: For a sustainable woody crop indust
Page 53 and 54: changed significantly since they we
Page 55 and 56: Figure 2.2 Biosystems Engineering p
Page 57 and 58: Whole-of-crop harvesting represents
Page 59 and 60: During the last decade the harvesti
Page 61 and 62: single row, as this would improve t
Page 63 and 64: 2.2.2.2 Weight Sugar System The Aus
Page 65 and 66: Table 2.1 Harvester Comparison Tabl
Page 67 and 68: The quality of cut may be less impo
Page 69 and 70: ate than a 170 tonne/ha crop of sta
Page 71 and 72: Dry Leaf 6.1 - 3.5 17.0 58.9 53.2 T
Page 73 and 74: Bulk density will be a key consider
Page 75 and 76: Table 2.4 EM levels in cane supply
Page 77 and 78: L/T L/T 60 0.97 0.71 80 0.92 0.66 1
Page 79 and 80: Total 7.5-26 16.5 Mallee System The
Page 81 and 82: • waiting for mill delivery of em
Page 83 and 84: perhaps at 10 - 20 km intervals. Th
Page 85 and 86: transport arrangements, harvest gro
Page 87 and 88: contractors and growers, and the fa
Page 89 and 90:
experience of the sugar industry wi
Page 91 and 92:
Table 2.11 Alternative harvest paym
Page 93 and 94:
onto the harvester. BR+F still send
Page 95 and 96:
Repairs and maintenance 2.10 Capita
Page 97 and 98:
Figure 2.14 and Table 2.14 describe
Page 99 and 100:
Sichter et al. (2005)), harvest and
Page 101 and 102:
Transport efficiencies may be possi
Page 103 and 104:
3. Transport and Storage Systems Tr
Page 105 and 106:
same time, the potential problems o
Page 107 and 108:
Figure 3.3 Articulated self-propell
Page 109 and 110:
• The harvester will not have any
Page 111 and 112:
Figure 3.7 Gross mass compared with
Page 113 and 114:
external factors dramatically impac
Page 115 and 116:
Figure 3.11 The effect of haulout t
Page 117 and 118:
3.3 Road Transport 3.3.1 Configurat
Page 119 and 120:
Figure 3.15 shows an example of the
Page 121 and 122:
Road distance one way < 20 km 70 km
Page 123 and 124:
Haul distance is largely outside th
Page 125 and 126:
3.6 Recommendations The nature of t
Page 127 and 128:
• The strategy offered lower tota
Page 129 and 130:
sugarcane billets are such that wit
Page 131 and 132:
• Transfer the whole tree product
Page 133 and 134:
Figure 4.5(b) Energy balance of con
Page 135 and 136:
2010). Table 4.2 presents a summary
Page 137 and 138:
4.4.2 Activated charcoal Activated
Page 139 and 140:
Nett Product Value ($/t) $475.00 $
Page 141 and 142:
Table 4.9 presents an estimation of
Page 143 and 144:
• Oil from leaf @ $2/kg • Synth
Page 145 and 146:
• The mallee oil would be extract
Page 147 and 148:
5. Industry and Business Structures
Page 149 and 150:
is conducted into tariff levels on
Page 151 and 152:
Bx is % brix in first expressed jui
Page 153 and 154:
Hildebrand (2002) estimated that th
Page 155 and 156:
also has a flow on effect to the sp
Page 157 and 158:
Sugar Industry Illustrative Example
Page 159 and 160:
with super size multi-lift bins ove
Page 161 and 162:
farmer vs. harvester) is the next l
Page 163 and 164:
6. Supply Chain Planning and Manage
Page 165 and 166:
Figure 6.1 Building blocks of the s
Page 167 and 168:
weighed against the costs of operat
Page 169 and 170:
• There is close contact between
Page 171 and 172:
6.4 Planning, Management Tools and
Page 173 and 174:
• Harvest and transport logistics
Page 175 and 176:
interface. The system allows users
Page 177 and 178:
Case Study 6.2 - Model Application
Page 179 and 180:
Relationships between sectors and p
Page 181 and 182:
7. Supply Chain Modelling and Econo
Page 183 and 184:
It was assumed that there was a fif
Page 185 and 186:
Table 7.2 Scenario two capital equi
Page 187 and 188:
Table 7.4 Fuel burn rates harvester
Page 189 and 190:
Figure 7.5 Effect of capital equipm
Page 191 and 192:
Figure 7.7 Effect of annual tonnes
Page 193 and 194:
30 1.8 7.0 12.3 17.5 50 1.1 4.3 7.6
Page 195 and 196:
8. Conclusions and Recommendations
Page 197 and 198:
Biomass bulk density has a large im
Page 199 and 200:
Vehicles used for infield haulout w
Page 201 and 202:
This can be compared with harvest a
Page 203 and 204:
While diversification can add value
Page 205 and 206:
Appendix 1: Comparative Assessment
Page 207 and 208:
and transport conditions. Billet le
Page 209 and 210:
that cane production is the most pr
Page 211 and 212:
on sugar only, other proceeds (mola
Page 213 and 214:
References Agnew, J 2002. A Partici
Page 215 and 216:
Enecon 2001. Integrated Tree Proces
Page 217 and 218:
Keating, BA, Antony, G, Brennan, LE
Page 219 and 220:
Ridge, DR and Linedale, AL, 1997. T
Page 221:
Willcox, T, Hussey, B, Chapple, D a
show all

Download (4Mb) - USQ ePrints - University of Southern Queensland

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?