Biorefineries

Sedlmeyer, F. B. (2011). Xylan as by-product of biorefineries Characteristics and potential use for food applications. Food Hydrocolloids, Vol. In Press, Corrected Proof, pp. ISSN 0268-005X... 

Wood chips can also be utilized as such to produce bioethanol. The cellulose and hemicellulose material is hydrolyzed in the presence of acids (H2SO4, HCl, or HCOOH) or enzymes to yield glucose and other monosaccharides [16]. Lignin is separated by filtration as a solid residue and the monosaccharides are fermented to ethanol, which, in turn, is separated from water and catalyst by distillation. Ethanol can be used not only as energy source but also as a platform component to make various chemicals, such as ethene and polyethene. Today green acetaldehyde and acetic acid from wood-derived bioethanol is manufactured by SEKAB Ab, at the Ornskoldsvik Biorefinery of the Future industrial park. 

An alternative possibility is that of the biorefinery. In this concept a few key chemicals would be isolated from a small number of process steps. Whilst there are many possibilities for this, in one example the raw material, say com, could be cmshed to release oil (the first key product). The resulting mass could then be fermented to give several key platform chemicals such as ethanol, lactic acid and acetic acid. This attractive concept would be more viable if all the cellulose and lignin components could be efficiently used in the fermentation process. 

Alternatively, an entirely new downstream process and product chain, using renewable raw materials, can be conceived (the biorefinery ). The chemistry will be more focused on that of oxohydrocarbons (particularly carbohydrates) rather than hydrocarbons. Understanding the materials chemistry of biomass and related products would need to be enhanced. However, work has already been undertaken to identify the top sugar-derived intermediates (Figure 1.9) on which down-stream chemical processing might be derived. 

Figure 1.12 Afuture biorefinery model based on a biochemical production plant.

To achieve sustainable production through biorefineries, engineers can look to specific chemical processes that draw on green technological alternatives. Whereas the principles... 

Development of value-added products from glycerol can help the total economics of an oilseed biorefinery. Propylene glycol is one such product. This chapter will present the development of catalysts that can convert glycerol to propylene glycol in high yields. Our work has focused on a class of catalysts based on Re, which as a cometal imparts important character to the catalysts. 

Biomass is a renewable resource from which various useful chemicals and fuels can be produced. Glycerol, obtained as a co-product of the transesterification of vegetable oils to produce biodiesel, is a potential building block to be processed in biorefineries (1,2). Attention has been recently paid to the conversion of glycerol to chemicals, such as propanediols (3, 4), acrolein (5, 6), or glyceric acid (7, 8). 

B. Kamm, M. Kamm, M. Schmidt, T. Hirth and M. Schulze, in Biorefineries-Industrial Processes and Products , (Eds. B. Kamm, P. R. Gruber, and M. Kamm), WILEY-VCH Verlag GmbH Co. KGaA, Weinheim, 2006, Vol. 2. 

John, G., Shankar, B.V., Jadhav, S.R. and Vemula, P.K (2010) Biorefinery a design tool for molecular gelators. Langmuir,... 

The biorefinery industry is marked with a feedstock related to the dispersed nature of its diet. The incoming raw material to a biorefinery is produced in a small scale (compared to an oil refinery), and in remote, distributed locations. Consequently, the biorefinery capacity is a parameter difficult to define due to the uncertainty in collection and blending of the feedstock. The next question is to what extent will the oil industry be involved in such operations and how will that affect the fossil to renewable ratio or the intake feedstock. 

Fernando, S. Adhikari, S. Chandrapal, C., et al., Biorefineries Current Status, Challenges, and Future Direction. Energy Fuels, 2006. 20 pp. 1727-1737. 

Combining fuel and power production, possibly extended with (bulk) chemical production by advanced integrated biorefinery process concepts... 

Huber, G. W. Dumesic, J. A., An overview of aqueous-phase catalytic processes for production of hydrogen and alkanes in a biorefinery. Catalysis Today 2006, 111, 119. 

The Department of Energy (DOE) is helping six firms build cellulosic biorefineries with grants totaling about 385 million. When fully operational, the six plants will produce more than 130 million gallons of cellulosic ethanol a year. DOE is also investing 375 million into three new Bioenergy Research Centers to speed up the development of cellulosic ethanol and other biofuels. 

Kamm, B., Gruber, P. R. and Kamm, M. (eds.) (2006). Biorefineries - Industrial Processes and Products Status Quo and Future Directions. Two Volumes. WILEY-VCH. 

The additional interesting part of Fig. 1.12 is the biorefinery, which uses biomass and waste, produces waste products C02 and ash, both to be recycled for the production of biofuels, heat and electricity and biomaterials. These biomaterials are highly oxygen functionalized for products such as alcohols, carboxylic acids and esters. A currently produced bioplastic is poly(lactic acid). A main cost factor is separation. 

A biorefinery scheme to produce chemicals from non-food biomass is given in Fig. 1.16. 

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