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The “high value” products are potentially most useful in the “development” phase of an industry,
however they will not be a significant component of an industry of the size envisaged.
An example of a high value utilisation strategy for a limited industry size could include:
• Harvest and post-harvest component separation. It is assumed that the leaf and twig material
would be separated at the processing site.
• Oil extraction from the leaf material, with a moderately low value of $4/kg for the extracted oil.
• Solar drying of the leaf and twig material as a thin layer.
• Utilisation of the woodchip and leaf material in a biomass furnace of appropriate design for
process heat and electricity generation.
The nominal value of the components could be:
• Oil from leaf and twig @ $4/kg: This gives a value to the separated leaf and twig material of
approximately $57/t freshweight, or approximately $34/t freshweight of the total material
harvested (leaf & twig : 60% of weight).
• Electricity, local ORC at grid displacement cost of $200/MW hr, giving a whole tree
freshweight value of $90/ton, and assuming that the leaf component is being used and its
moisture content has been reduced to no greater than fresh moisture content, and;
• Local thermal (hot water & steam) for process applications: assuming only 40% of the energy
in the waste heat streams is captured utilized (approximately 30% overall heat recovery and
utilization), and that this heat displaces LPG, the value of the total product will be $60/t on a
freshweight basis.
The tree value for this scenario would be in the order of $185/t. While this may be possible in a small
scale industry, this would not be considered a potential scenario for a larger industry.
The cost pressures on an industry which attempts to expand will be significant because of reducing
product values, however strategic combination of components, along with reductions in cost will
clearly be the only viable strategy.
A large scale operation in the future may involve:
• Harvest and post-harvest separation of components at a nearby nodal point.
• Oil extraction from the leaf, drying and densification of the leaf.
• Transport of densified leaf and woodchip material separately to centralised facilities where
processes such as the metallurgical charcoal and bio-crude of synthesised diesel are produced.
Significantly, initial indications are that the technologies being developed for the production of
synthesised diesel would appear to be suited for moderate size facilities which could be decentralised.
If not, the model being investigated by the Sugar industry involves the production of bio-crude and
transport this higher value product to major centralised facilities (Hobson, pers com, 2011).
This scenario could result in gross product values in the order of:
• Oil from leaf @ $2/kg
$12/t freshweight (FW) on whole tree basis.
• Metallurgical Charcoal
$45/t, whole tree FW with solar drying of leaf, and:
• Synthesised Diesel
$46/t FW assuming 50% recovery of chemical energy
in gas stream from the charcoal process.
This would give a total feedstock value in the order of $103/t, with reduced oil recovery efficiency
because of the production of metallurgical charcoal.
Alternatively the local recovery of oil from leaf and twig material, followed by the utilisation of all
feedstock for synthesised oil production,
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