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There is a large project in Western Australia involving the thermochemical processing of an agroforestry resource. The project is being conducted by Western Power, a local electricity producer, and involves production of electricity and activated carbon from the pyrolysis of Mallee. A large pilot scale plant has been constructed at Narrogin, a small town approximately 170km south east of Perth. The technology behind the process was developed by Dr Paul Fung at the CSIRO Forest Products Laboratory, Clayton. If successful, the project will enable Western Power to fulfil its obligation in developing renewable energy streams that will amount to at least 2% of its total energy production, the target imposed under the Federal government’s renewable energy policy. Moreover, success of the project will also provide Western power with large quantities of activated carbon, an expensive commodity currently produced globally in relatively small quantities. During the oil crisis in the 1970s, the pyrolysis of coal and oil-shale was investigated in Australia at CSIRO. The objective of both streams of research was to produce liquid hydrocarbons from solid fossil fuels for use in transportation. The research was eventually abandoned due to a decline in the oil crisis and resultant reduction in crude oil prices. During the 1980s, the Chemical Engineering department of Melbourne University, under the leadership of Mike Connor, modelled various pyrolytic phenomena in wood particles 6,22 . The research embodied in the current project is a part of the Melbourne University, School of Forestry pyrolysis research program. This program began with an investigation into the low temperature fast pyrolysis of Radiata pine for phenols production. The research program involved development of a pyrolysis technology that minimised many of the characteristics which confound commercial utilisation of pyrolysis liquids. These detrimental characteristics include: • Low thermal stability • Extremely high complexity • Low yield of individual compounds • High tar content • Low pH The origin of these characteristics has been briefly reviewed and the low temperature, fast pyrolysis process developed at the University of Melbourne is designed to mitigate their negative influence on oil quality through elimination or minimisation of the processes which result is these characteristics. 1.2 Review of essential oil extraction Essential oils may be defined simply as volatile organic, condensable compounds obtained from plants. Different species produce different essential oils, and such oils may be concentrated in the flowers, fruit, leaves, roots, seeds and even the bark of plants. In plants, essential oils are typically comprised of numerous compounds with perhaps one or two dominating the mixture. Often, these oils need to be modified in some way in order to meet specific commercial needs and this is usually achieved through blending, purification and fortification. The commercial usage of essential oils may be grouped into three categories and these are pharmaceutical, fragrances/flavours and industrial. The pharmaceutical properties of essential oils have been recognised since antiquity but only in the last 500 years or so have these properties been investigated with any scientific rigour. In the early sixteenth century, the Swiss medical reformer, Bombastus Paracelsus von Hohenheim (1493-1541), proposed that the medicinal properties of a plant are caused by some constituent, the quinta essentia, and that the goal of pharmacy should be the isolation of this substance. Today, the quinta essentia in medicinal products is referred to as the ‘active ingredient’ and is either derived from natural products, such as essential oils, or is synthesised. Many essential oils are highly aromatic and are therefore used 10
as fragrances in their own right or as ingredients in perfume manufacture. Essential oils that possess characteristic flavours are used by the flavour industry. Industrial applications of essential oils include solvents, cleaners and raw material for the synthesis of substances not available or impractical to source from nature. Essential oils may be extracted from the plant by a variety of techniques. For example, steam distillation is the preferred method for isolating oils present within leaves, whereas pressing is the preferred technique for extracting oils associated with fruit or flowers. World trade of essential oils is difficult to determine. This is because essential oils may be traded as raw oil, refined/upgraded oil, or as a component of some manufactured product. Production figures are also difficult to obtain because oils of commercial significance are extracted from more than 300 plant species distributed throughout many different countries. However, some statistics are available. Table 1.2.1 lists the world trade of essential oils, including fragrances (perfumes) and flavours. Table 1.2.1. World trade of essential oils. Source: United Nations International Trade Yearbook 1999 and 2002 World Trade In Essential Oils, Perfumes And Flavours - US$ million 1986 1990 1994 1998 2002 Est. 1986–98 Average % pa Exports Imports 2,149 2,008 4,122 4,206 5,051 6,811 7,435 4,802 8,254 5,316 +10.9 +10.7 From examination of Table 1.2.1, it is apparent that the essential oil industry is a multibillion-dollar industry which is growing very rapidly. World production of essential oils is estimated to be between 100,000-110,000 tons, not including turpentine oil. Eucalyptus leaves contain essential oil and it is this oil that gives the leaves their characteristic fragrance. From the time of European settlement, there has been considerable interest in the properties of essential oils of indigenous Australian plants, and in particular Eucalyptus plants. In 1788, the genus was named Eucalyptus by L’Heriter. The word is derived from the Greek words eu (well) and kalypto (I cover) and eludes to the observation that the flower-bud covers the stamens until they are fully developed. Medicinally, Eucalyptus oil is used for the treatment of bronchial ailments, where it works by stimulating mucous secretion, and as an antiseptic agent. The active therapeutic agent in Eucalyptus oil is 1,8-cineole, the structure of which is provided in Figure 1.2.1. OH 1,8-Cineole Figure 1.2.1. Structure of 1,8-cineole As a treatment for bronchial ailments, Eucalyptus oil is generally used as an expectorant, where it is administered by inhalants, embrocations, liniments, soaps, gargles, lozenges and dentrices. Eucalyptus oil also has mild anaesthetic properties. 11
Page 1: Thermochemical Processing of Agrofo
Page 4 and 5: © 2006 Rural Industries Research a
Page 6 and 7: Table of contents 1 2 3 4 5 6 7 8 9
Page 8 and 9: 5.4.2.2 5.4.2.3 5.5.1 5.5.2 5.6.1 5
Page 10 and 11: 4.4.4.1 5.1.1 5.2.1 5.3.1 5.4.1.1 5
Page 12 and 13: Executive summary What the report i
Page 14 and 15: Under the conditions that resulted
Page 16 and 17: net increase of 28% compared to sim
Page 18 and 19: Due to the sensitivity of the pyrol
Page 20 and 21: It has been found that the composit
Page 22 and 23: carbon dioxide, carbon monoxide 9,1
Page 24 and 25: TGA studies have revealed that hemi
Page 28 and 29: The 1,8-cineole content of Eucalypt
Page 30 and 31: Chapter 2: Objectives The overall a
Page 32 and 33: 3.1.5 Preparation of sand for the r
Page 34 and 35: A mechanical stirrer, the purpose o
Page 36 and 37: A separate needle valve was employe
Page 38 and 39: Product collection train assembly T
Page 40 and 41: In the current study, a DB-1701 col
Page 42 and 43: to the chromatographic method (cons
Page 44 and 45: The ethylenediamine to cupric ion r
Page 46 and 47: Table 3.6.2. Experimental design fo
Page 48 and 49: Modification 2: recovery of Eucalyp
Page 50 and 51: 4.1.2 Identification by comparison
Page 52 and 53: Table 4.1.4.1. Summary of lignin de
Page 54 and 55: The retention times of the compound
Page 56 and 57: treatment. The balance of the water
Page 58 and 59: 4.4.2 Holocellulose determination b
Page 60 and 61: 4.4.4 Analysis of the properties of
Page 62 and 63: 1. Survey the influence of various
Page 64 and 65: of the material converted to volati
Page 66 and 67: The selectivity of the process towa
Page 68 and 69: The effect of fluid bed mass on the
Page 70 and 71: Table 5.4.2.1. Comparison of cellul
Page 72 and 73: 1.2. The parameter values employed
Page 74 and 75: Chapter 6: Influence of selected op
Page 76 and 77:
Yield (%m/m) 6 5 4 3 2 1 0 Figure 6
Page 78 and 79:
The proportion of feed converted to
Page 80 and 81:
Chapter 7: Optimisation of essentia
Page 82 and 83:
The very large improvement in cineo
Page 84 and 85:
A schematic diagram of each of the
Page 86 and 87:
14 17 19 11 12 9 13 15 16 10 1. Gla
Page 88 and 89:
8.2 Evaluation of the fast pyrolysi
Page 90 and 91:
Table 8.2.1.3. Yield of solid resid
Page 92 and 93:
Table 8.2.2.3. Yield of solid resid
Page 94 and 95:
The influence of carrier gas flow r
Page 96 and 97:
Chapter 9. Assessment of any health
Page 98 and 99:
Table 9.1.2. Toxicity information o
Page 100 and 101:
3.0 Synonyms Bio-oil, pyrolysis liq
Page 102 and 103:
• Vapour is irritating to the eye
Page 104 and 105:
1-tridecene 2,6,10,14-tetramethylpe
Page 106 and 107:
Chapter 11: Market analysis This ch
Page 108 and 109:
Table 11.1.2.1. World production of
Page 110 and 111:
11.2.3 World consumption of furfury
Page 112 and 113:
11.3.2 Guaiacol There is relatively
Page 114 and 115:
Current applications of isoeugenol
Page 116 and 117:
will involve passivation by a proce
Page 118 and 119:
produces around 14 billion litres/a
Page 120 and 121:
Appendix 1. Mass balances associate
Page 122 and 123:
Appendix 2. Mass balances associate
Page 124 and 125:
Appendix 3: Quantification data for
Page 126 and 127:
Phenol Trial 1.1 Trial 1.2A Trial 1
Page 128 and 129:
Isoeugenol Trial 1.1 Trial 1.2A Tri
Page 130 and 131:
Syringol Trial 1.1 Trial 1.2A Trial
Page 132 and 133:
Furfural Trial 1.1 Trial 1.2A Trial
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Furfural methyl acetal Trial 1.1 Tr
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Retention Time 15.177 15.667 18.246
Page 138 and 139:
Retention Time 15.177 15.667 18.246
Page 140 and 141:
Retention Time 15.177 15.667 18.246
Page 142 and 143:
Retention Time 15.177 15.667 18.246
Page 144 and 145:
Retention Time 15.177 15.667 18.246
Page 146 and 147:
130 Standardised Peak Area Retentio
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Retention Time 3.205 3.268 3.989 4.
Page 150 and 151:
Retention Time 3.205 3.268 3.989 4.
Page 152 and 153:
Retention Time 3.205 3.268 3.989 4.
Page 154 and 155:
Retention Time 3.205 3.268 3.989 4.
Page 156 and 157:
Page 158 and 159:
Page 160 and 161:
Sample Steam Extract 1 Ethanol Extr
Page 162 and 163:
Sample Steam Extract 1 Ethanol Extr
Page 164 and 165:
15. Klein, M.T. and P. Virk. 1981.
Page 166 and 167:
45. Vuori, A. 1986. Pyrolysis Studi
Page 168 and 169:
78. Faix. O., I. Fortmann, J. Breme
Page 170 and 171:
112. Kurth, E.F., and G.J. Ritter.
Page 172:
Thermochemical Processing of Agrofo
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