Bio-based energy

WEI 07] Weiss M., Patel M., Heilmeier H., et al, Applying distance-to-target weighing methodology to evaluate the envirormiental performance of bio-based energy, fuel and materials , Conservation and Recycling, vol. 50, no. 3, pp. 2017-2028,2007. 

Data printad in italica represent rough estinate. Data printed in bold are used for environmental assessment Cradle (o>fac(ory gate anal is. Without bio-based feedstock and bio based energy byproducts used within the process. 

All these chapters describe the smart use of reactor design and process integration to increase the efficiency and reduce the emissions when using fossil fuels as energy source. Of course, intensified systems can also be used for bio-based energy sources. Chapter 8 reports the possibility to convert biomass into substitute natural gas. The chapter describes how both packed beds and fluidized bed reactors can effectively be used to improve the methanation reaction so that the products of biomass gasification can be converted into a more sustainable methane stream. 

The potential of combining a lower need for deoxygenation and a higher product value is illustrated in Fig. 2.15. It shows that the selective incorporation of oxygen into a hydrocarbon, as done in the petrochemical industry, is very expensive. In contrast, the bio-based alternative enjoys two advantages. Firstly, the feedstock is cheaper than crude oil, even on an energy and carbon base, as discussed above. Secondly, its selective deoxygenation has been proven to cheaper than the petrochemical route in a few cases, e.g., for ethanol and furfural. The same can be expected for other biomass derivates in the future. 

The increasing cost of fossil fuels and the concerns related to their environmental impact and greenhouse gas effect, as well as the need of securing energy supplies, are accelerating the transition to a bio-based economy. Various R D tools need to be provided to realize this transition. The replacement of fossil fuel by bio-mass has been addressed in recent years worldwide. The EU, for example, has defined a target to double the share of renewable energy from 6% in 1997 to 12% by 2010 (COM 1997 599). 

A biorefinery is a facility that integrates biomass conversion processes and eqtrip-ment to produce fuels, power, and value-added chemicals from biomass. Biorefinery is the co-production of a spectram of bio-based products and energy from biomass. The biorefinery concept is analogous to today s crude oil refinery. Biorefinery is a relatively new term referring to the conversion of biomass feedstock into a host of valuable chemicals and energy with minimal waste and emissions. 

The development of bio-based succinic acid production was carried out as the NEDO (New Energy and Industrial Technology Development Organization, an implementing agency of METI in Japan) project from 2004 to 2006, and the possibility of bio-based materials was confirmed. 

A good example of a white biotech process in the pharmaceutical area is our route to the antibiotic cephalexin, practiced on a large industrial scale for several years now. By advanced enzyme and metabolic engineering we were able to replace the traditional 10-step, mainly chemical synthesis (Fig. 29.3A) by a fermentative route followed by two mild enzymatic steps (Fig. 29.3 B). The white biotech process has been shown recently to use far less energy (-65%), less input of (harsh) chemicals (-65%), is water-based, generates less waste, and is very cost-effective (-50%) (Bruggink, A.). Again, this is a bio-based process where environmental and economic benefits go hand in hand and for which there is no competitive chemical alternative (EuropaBio and McKinsey Company, 2003 DSM position document, 2004). 

The ultimate in sustainable catalytic processes is the integration of chemocat-alytic and/or biocatalytic steps into catalytic cascade processes that emulate the metabolic pathways of the cell factory. It is an esthetically pleasing thought that, in the future, fuels, chemicals and polymers could be obtained from carbon dioxide and water as the basic raw materials via biomass, using sunlight as the external source of energy and water and supercritical carbon dioxide as solvents. The important difference between this bio-based scenario and the current oil-based one is the time required for renewal of the feedstocks. 

In Chapter 1 (Section 1.6.1, Bio-based Economy) it was noted how white biotechnologies contribute to sustainability. We may cite, as an additional example, that DSM s route to the antibiotic cephalexin (a combination of a fermentation and an enzymatic reaction with respect to multistep chemo-synthesis) reduces of 65% the materials and energy used, and about 50% the variable costs [153]. Other examples of biocatalysis and white biotechnologies used industrially by DSM are summarized in Table 2.5. 

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