Thermochemical technology, biomass

Biochemical technologies for conversion of biomass are much more common than thermochemical technologies. There has been a great deal of discussion in the literature about whether biochemical or thermochemical technologies would be more appropriate for the conversion of biomass into fuels. Criticism of biochemical methods typically... 

Lujuefaction. Eigure 21 outlines most of the biomass Hquefaction methods under development. There are essentially three basic types of biomass Hquefaction technologies, ie, fermentation, natural, and thermochemical processes. 

When implementing a biomass-based thermochemical conversion system, it is important to critically evaluate the feedstock characteristics such as cost, distribution, mass, and physical and chemical properties. The feedstock qualities must be considered when matching feedstocks with a proper conversion technology. 

Biomass-based processes for the production of hydrogen can be either thermochemical or biological and can produce this clean carrier directly or through an intermediate, storable product. Also, the use of coproducts has to be addressed to improve the process economics and in view of the sustainability of using this natural resource. A recent overview of the status of the different technologies is given in an IEA/NREL review5 and further by Czernik et al.8... 

This review limits itself to the treatment of high-temperature thermochemical biomass conversion technologies. There are very good overviews of biological conversion technologies for hydrogen production, for example, Ni et al.13 and Zaborsky.29... 

The present chapter discusses aspects, known by the authors, of (a) biomass as feedstock, (b) the concept of bio-refinery, (c) thermochemical routes from lignocellulosic biomass to fuels, and (d) the contribution of catalytic technology. The main focus will be on the catalytic conversion of fast pyrolysis oil into fuels with regard to problems encountered currently and the challenges for future research and development. 

The main drawback with the thermochemical route for biomass utilization is the strong dependence on scale-up. To be competitive, the capacity has to be of the order of a small oil refinery (approx. 1 million tonnes per year), but there then exists the problem of the cost of transporting the biomass relatively long distances to this production capacity. Pyrolysis or related technologies ( flash or fast ) could transform biomass into liquid products that are more easily transported, and these liquid products could then be the input for a large, centralized... 

Biorefineiy is the process of extracting valuable chemicals and polymers from biomass. The main technologies to produce cheiuicals from biomass are (a) biomass refining or pre-treatment, (b) thermochemical conversion (gasification, pyrolysis,... 

Industrialbiobased products have enormous potential in the chemical and material industries. The diversity of biomass feedstocks (sugars, oils, protein, lignocellulosics), combined with the numerous biochemical and thermochemical conversion technologies, can provide a wealth of products that can be used in many applications. Targeted markets include the polymer, lubricant, solvent, adhesive, herbicide, and pharmaceutical markets. Industrial bioproducts have already penetrated some of these markets, but improved technologies promise new products that can compete with fossil-based products in both cost and performance. 

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