Abstract
During recent years, in the United States (US) and European Union (EU) a large number of industrial initiatives on so-called “lignocellulosic advanced biofuels” have taken off. The second generation biofuels are today on the ambitious path from lab or pilot scale to demonstration scale in order to facilitate commercial production. In fact, lignocellulosic biomasses are among the most promising feedstocks to develop sustainable biofuels, either from residual (e.g. agricultural wastes like corn stover, wheat staw) or dedicated energy crops (eg.,perennial grasses, short rotation woody biomass). Different types of processing technologies have been investigated and are being demonstrated in pilot scale, namely, biochemical, thermochemical or hybrid: in the hybrid configuration, a combination of thermochemical and biochemical approaches are considered and integrated in a single plant.
Various industrial plants have been designed and built in both the EU and US during the last few years: these state-of-art conversion systems represent the first cases of large scale industrial biorefineries. In the present work, a review of the most relevant ongoing initiatives in EU and US was carried out: the common element of all these projects is represented by the use of lignocellulosic biomass as input material. More than 80 industrial projects in the EU and US have been identified, classified and elaborated, according to location, process type, feedstock, plant scale (feedstock in, product out), type of products, technologies and investment cost (Balan et al, 2013). Processes aiming at gasoline-substituting biofuels versus diesel- like biofuels were separately considered in the analysis, e.g. ethanol or biocrude from advanced thermochemical conversion, as well as the opportunities in terms of new biorefinery pathways. Projections on production costs were considered and discussed. The need for appropriate policy framework is also discussed, examining the most relevant differences between the US and the EU regulatory conditions.
So far, biochemical based industrial initiatives seems to be leading the scenario, with the large commercial plants being constructed using these technologies. Nevertheless, a renewed effort has been recently allocated by various industries to implement thermochemical-based biofuel production projects. Some of these plants are expected to come into full commercial operation in 2014.