Thermo-chemical conversion biomass

Emission reduction for all types of thermo-chemical conversion of biomass. Ash recycling and cleaning. 

Thermo-chemical conversion summarizes all conversion processes of biomass into a solid, liquid or gaseous fuel based on heat. Therefore... 

Biomass Sources Biomass Production and Supply Thermo-Chemical Conversion Physico-Chemical Conversion Blo-Chemical Conversion Outlook... 

The most widely use of biomass is the provision of heat released during combustion of solid biofuels. But combustion is only one conversion process among others based on a heat-induced chemical conversion of the organic material. Therefore within the following explanations we first discuss the basics of such thermo-chemical conversion processes. Then we focus on the technical implementation of these principles in conversion plants. 

FIGURE 4 Example of thermo-chemical conversion of wood. [From Kaltschmitt, M., and Hartmann, H. (2001). "Energy from Biomass, Springer, Berlin, Heidleberg, Germany. (In German.)]... 

Zhang, L., Xu, C., Champagne, P. Overview of recent advances in thermo-chemical conversion of biomass. Energy Conversion and Management 51 (2010) 969-982. 

Panwar, N.L., Kothari, R., Tyagi, V.V., 2012. Thermo chemical conversion of biomass — eco friendly energy routes. Renewable and Sustainable Energy Reviews 16 (4), 1801—1816. 

Second-generation biofuel technologies make use of a much wider range of biomass feedstock (e.g., forest residues, biomass waste, wood, woodchips, grasses and short rotation crops, etc.) for the production of ethanol biofuels based on the fermentation of lignocellulosic material, while other routes include thermo-chemical processes such as biomass gasification followed by a transformation from gas to liquid (e.g., synthesis) to obtain synthetic fuels similar to diesel. The conversion processes for these routes have been available for decades, but none of them have yet reached a high scale commercial level. 

Thermo-chemical gasification is the conversion by partial oxidation at elevated temperatures of a carbonaceous feedstock into a low or medium energy content gas (Saxena et al., 2007). Gasification of coal is now well established, and biomass gasification has benefited from the activity in this sector and is developing rapidly. However, the two technologies are not directly comparable due to differences between the feedstocks (e.g. char reactivity, proximate composition, ash composition, moisture content, density). 

Stahl, K., Neergaard, M., Stratton, P., Nieminen, J., IGCC power plant for biomass utilisation Vamamo, Sweden, presented at Developments in Thermo-chemical Biomass Conversion, Banff, Canada, May 1996. 

Bandi A., and F, Baumgart (2000), Fast pyrolysis liquid feed to a FLOX burner. In Proceedings of Progress in Thermo-chemical Biomass Conversion, Tyrol, Austria, 17-20 September. 

There has been considerable progress in the science and technology of thermo-chemical biomass conversion since the previous conference on Developments in Thermochemical Biomass Conversion in Banff, Canada, in 1996. This fifth conference again covers all aspects of thermal biomass conversion systems from fundamental research through applied research and development to commercial applications to reflect the progress made in the last four years. 

Both biomethane production paths complement one another in an ideal way. While the thermo-chemical route focuses on solid biofuels e.g. wood, straw) the bio-chemical route uses wet biomass e.g. animal manure, maize silage). The latter will be realized with plant capacities in the one-digit thermal MW-scale and the former in the two- to three-digit MW-scale. The provided product is basically similar and can be used together with natural gas in any mixture. The erection of the biogas and Bio-SNG conversion plants can be planned directly at the established gas grid. 

The purpose of biomass conversion is to provide fuels with clearly defined characteristics that meet given fuel quality standards. Such defined solid, liquid, or gaseous fuels can then be used to meet a specific supply task efficiently. To ensure that these fuel quality standards are met and these biomass-based fuels can be used with a high efficiency in conversion devices (like engines, turbines) upgrading is needed. Here, a distinction is made between thermo-chemical, physico-chemical, and biochemical conversion processes to accomplish this aim (see Glossary). 

There is not only a need but also an urge to use waste biomass resources in the production of biofuels, due to the many envirorunental and economic impacts from the conventional fossil-based transportation fuels. The conversion routes applied to biomass for fuel production widely include thermo-chemical, hydrothermal and biochemical. All the three conversion methods are well-suited to achieve the energy requirements for being ecofriendly processes. However, in the present context both thermochemical and hydro-thermal conversion are foimd effective to produce an energy dense liquid bio-oil that could not only be used as a transportation fuel but also for heat and power generation. 

With the growing industrial interest in the production of biofuels, the most important areas that need attention and research seem to be (i) scale-up, (ii) cost efficiency, (iii) better fuel properties, (iv) norms and standards for producers and end-users, (v) environment health and safety issues in biomass io el handling, transportation and usage, (vi) encouragement to implement thermo-chemical processes and applications, (vii) efficient utilization of byproducts for value-added chemical or material production, and (viii) information dissemination. The biomass conversion process can be economically viable if used in an integrated manner for generation of other marketable co-products in addition to the primary biofuel product, thus contributing to sustainable development. 

Balat, M., Balat, M., Kirtay, E., Balat, H. Main routes for the thermo-conversion of biomass into fuels and chemicals. Part 1 Pyrolysis systems. Energy Conversion and Management 2009, 50,3147-3157. 

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