Fast Pyrolysis of Wood

All of the studies mentioned are directed to lignins derived from pulp and paper manufacture. This requires that a traditionally conservative pulp and paper industry embark on further development as a chemical producer. However, Helena Chum and her colleagues (Chapter 11) derive their phenolics from lignin by fast pyrolysis of wood rather than as byproducts from the pulp and paper industry. Opportunities might be better for development of adhesives from a chemical manufacturer drawing on waste wood as a raw material much the same as has developed in the production of furan resins derived from agricultural residues described by Bill McKillip (Chapter 29). 

Lede J, Panagopoulos J, Li HZ and Villermaux J, Fast Pyrolysis of Wood direct... 

Lede J., Panagopoulos J., Li H.Z., Villermaux J. (1985) Fast Pyrolysis of Wood. Direct Measurement and Study of Ablation Rate. Fuel, 64, 1514-1520. 

Tlie heavy metals are collected with the char and the liquid bio-oil contains only traces of metals. The real samples show the same behaviour as those prepared in the laboratory. Fast pyrolysis of wood impregnated with A1 and Cu complexes gave similar results aluminum and copper are predominantly found in the char fraction. 

The continuous fast pyrolysis of wood sawdust has been studied in a Lapple type (2.8 x 10" m diameter) cyclone reactor heated between 893 and 1330 K ( ). The wood particles carried away by a flow of steam enter tangentially into the cyclone on the inner hot walls of which they move and undergo decomposition. Mass balances show in all the cases, a very low fraction of char (< 4 %) while the gasification... 

Figure 7. Variation of the gasification yield X as a function of wall temperature in the fast pyrolysis of wood sawdust in a cyclone reactor comparison with the fusion" temperature of 739 K.

Zhang H, Carlson TR, Xiao R, Huber GW. Catalytic fast pyrolysis of wood and alcohol mixtures in a fluidized bed reactor. Green Chem 2012 14 98-110. 

Carlson, T.R., et al., 2011. Production of green aromatics and olefins by catalytic fast pyrolysis of wood sawdust. Energy Environmental Science 4 (1), 145—161. 

Fast pyrolysis of biomass provides a method for the production of phenolics that has the potential to replace at least 50% or more of the phenol in phenol-formaldehyde thermosetting resins. The gel tests indicate that the P/N fractions from pine sawdust pyrolysis with paraformaldehyde have shorter gel times than commercial plywood resins such as Cascophen 313, even without prepolymer formation. A novolak formulation has been prepared using 1 1 by volume of phenol and P/N fraction and about half of the amount of formaldehyde that would be used than if phenol alone were employed. Very promising resols have also been made with a similar substitution of the P/N fraction for phenol. Wood testing and resin formulation development are ongoing activities. The projected economics suggest that additional research and development of this process are fully warranted. 

Gerdes C, Meier D, Kaminsky W, Flash pyrolysis of industrial biomass wastes , Meier D, Ollesch T, Faix 0, Fast pyrolysis of impregnated waste wood - The fate of hazardous components ,... 

Hata T, Meier D, Kajimoto T, Kikuchi H, Imamura Y, Fate of arsenic after fast pyrolysis of chromium-copper-arsenate (CCA) treated wood . 

Piskorz J, Radlein R, et.al. (1995) Fast Pyrolysis of Pretrealed Wood. In Proceedings of the Second Biomass Conference of the Americas, National Renewable Energy Lab, Golden, CO. 

Meier D., Ollesch T.. Faix O. (2000) Fast Pyrolysis of Impregnated Waste Wood-the Fate of Hazardous Components. In Progress in Thermocbemicai Biomass Conversion, (Ed, by T. Bridgwater), submitted for publication,... 

Fate of Arsenic After Fast Pyrolysis of Chromium Copper-Arsenate (CCA) Treated Wood... 

Fast Pyrolysis of Impregnated Waste Wood - The Fate of Hazardous Components... 

Fast pyrolysis of waste wood has been studied in a small pilot plant with a nominal capacity of 5 kg/h. A schematic diagram is presented in Figure 3. 

Fig. 1 Schematic diagram of pilot plant for fast pyrolysis of waste wood.

XRF analysis was also performed on pyrolysis oil and char from fast pyrolysis of real wood waste obtained from a commercial collection and separation site. The XRF data show similar results compared to the samples impregnated in the laboratory. Various mono-fractions from the collection site were pyrolyzed such as cable drums, fences, railway sleepers, particle boards and window frames. The results are presented in Table 6 and are based on the whole oil whereas the data presented in (4) only refer to the cleaning oil fraction. Nothing could be detected in the oils collected from the condensation train. 

The results presented here show the general trend if chloro-organic compounds are present in the feedstock. The amount of chloro-organics in the feedstock used here were somewhat unrealistic but selected to better understand and measure PCDD/F formation and concentration in the products of fast pyrolysis. In reality, there are no mono-fractions of wood contaminated only with chloro-organic compounds, Generally, pyrolysis of waste wood mixtures results in a much less contaminated oil as presented in this study. However, further investigations are necessary to prove if de novo synthesis takes place during fast pyrolysis of contaminated waste wood. 

The results of this study show that fast pyrolysis of contaminated waste wood is technically feasible without any restrictions. Heavy metal compounds introduced by wood preservatives are almost conpletely mechanically separated by cyclones together with the charcoal. 

Record 1989 Annual Convention of the British Wood Preservers Association, 35-42 Dickson RL and Walker JCF (1997) Selecting wood quahty characteristics for pines. In CTIA/IUFRO International Wood Quality Workshop Timber Management toward wood quality and end-product value Quebec City, Chapter 4 45-52 Diebold JP and Bridgewater AV (1997) Overview of fast pyrolysis of biomass for the production of liquid fuels. In Bridgewater AV and Boocock, DGB (eds). Developments in thermochemical biomass conversion. Blackie Academic and Professional, London, Vol. 2 5-23... 

Piskorz, J. Scott, J.S. Radlein, D "The composition of oils obtained by the fast pyrolysis of different woods." In This Volume. 

Composition of Oils Obtained by Fast Pyrolysis of Different Woods... 

Liquids obtained by fast pyrolysis of four different woods were analysed. On addition of excess water they separated into water-soluble and water-insoluble fractions. The former which is principally of carbohydrate origin was shown by HPLC analysis to consist of sugars, anhydrosugars and low molecular weight carbonyl compounds. The latter was shown by NMR to be a "pyrolytic lignin". In this way 81% to 92% of the organic content of the liquids has been characterised. 

Huber et al. performed the catalytic fast pyrolysis of pine wood with spray-dried ZSM-5 in a bubbling fluidized-bed reactor with co-feeding of different alcohols, viz. methanol,... 

As described in the previous section. Brown et al. obtained an aromatic yield of 1% in the catalytic fast pyrolysis of milled wood lignin with ZSM-5 at 600°C, which was considerable lower than the yields obtained from cellulose and hemicellulose [286]. Also, the coke yield from lignin (59%) was much higher. Huber et al. used the lignin residue obtained after H SO hydrolysis of maple wood as a substrate for pyrolysis in a fluidized-bed reactor with spray-dried ZSM-5 at 600°C [298]. Next to lignin, this substrate also contains humic residue, a compound also composed of phenolic entities. An aromatic and olefin yield of only 2% and 1% was obtained, compared to respective yields of 15% and 7% from pure maple wood. The coke yield from the solid residue (69%) was also much higher than the coke yield from maple wood (32%). 

The types of biomass, especially ash content, heating rates, and hot vapor residence times, have a major effect on the product composition (Jahirul et al., 2012). The typical product composition for fast pyrolysis of clean dry wood is 75 wt.% liquid, 12 wt.% char (usually consumed in the process for heat), and 13 wt.% gas, compared to slow pyrolysis which is 30 wt.% liquid, 35 wt.% char, and 35 wt.% gas (Bridgwater, 2012a,b). 

Scott, D.S., et al., 1988. The role of temperature in the fast pyrolysis of cellulose and wood. Industrial Engineering Chemistry Research 27 (1), 8—15. 

Kinetic parameters of fast pyrolysis were derived while assuming a single process for the decomposition of wood, including three parallel first-order decay reactions for the formation of the product classes. This is the so-called Shafizadeh scheme [56]. The three lumped product classes are permanent gas, liquids (biooil, tar), and char a classification that has become standard over the years. The produced vapors are subject to further degradation to gases, water and refractory tars. Charcoal, which is also being formed, catalyzes this reaction and therefore needs to be removed quickly [57]. 

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