A bioreflnery is a facility that integrates biomass conversion processes and equip­ment to produce fuels, power, and value-added chemicals from biomass. The biore­flnery concept is analogous to today’s crude oil refinery, which produces multiple fuels and products from petroleum. Bioreflnery refers to the conversion of biomass feedstock into a host of valuable chemicals and energy with minimal waste and emissions. In a broad definition, biorefineries process all kinds of biomass (all or­ganic residues, energy crops, and aquatic biomass) into numerous products (fu­els, chemicals, power and heat, materials, and food and feed). Figure 7.2 shows a schematic diagram of a biorefinery.

A biorefinery is a conceptual model for future biofuel production where both fuels and high-value coproduct materials are produced. Biorefineries can simultane­ously produce biofuels as well as bio-based chemicals, heat, and power. Biorefiner-

ies present more cost-effective options where bio-based chemicals are coproducts of liquid fuel. Future bioreflneries would be able to mimic the energy efficiency of modern oil refining through extensive heat integration and coproduct development. Heat that is released from some processes within the biorefinery could be used to meet the heat requirements for other processes in the system (WI2007).

Reliable designs of equipment for the thermochemical stages of biomass conver­sion have yet to be widely demonstrated and shown capable of continuously produc­ing synthesis gas of the required quality. Synthesis gas has to be free of nitrogen; this requires the use of oxygen (expensive), a pyrolytic process optimized for gas, or a multistage process. The main nontechnical barriers to acceptance of liquid bio­fuels, especially in the transport sector, relate to the costs of production, available markets, taxation policies, and legislation, as well as blending and distribution. From an economic point of view the use of agricultural crops, without subsidy, is too ex­pensive to produce either bioethanol or biodiesel at a price competitive with untaxed petrol or diesel fuel, while processes for using lower cost lignocellulosic materials have not been perfected. There are a number of pilot-scale and demonstration plants operating, under development, or planned with fully commercial developments not expected for another decade or two (GBRP 2007).

Developed and developing countries clearly have different goals in the develop­ment of biomass energy. Biomass energy is promoted in developed countries as a re­placement for fossil fuels, particularly in the transportation sector, whereas its use serves basic livelihood purposes in developing countries. Combining higher-value products with higher-volume energy production and employing any combination of conversion technologies has the greatest potential for making fuels, chemicals, ma­terials, and power from biomass competitive. Obtaining modern biofuels, biopower, and bioproducts from biomass can be realized only in integrated biorefineries. This chapter reviews current biorenewable fuel valorization facilities as well as the future importance of biorefineries. The development of biorefinery technologies is impor­tant, and these technologies are also very promising.

Broadly speaking, the term biorefinery can be thought of as a concept of mul­tiple products from various biomass feedstocks. A biorefinery processes biomass into value-added product streams. In theory, anything that uses biomass and makes more than one product is a biorefinery. A biorefinery is analogous to a petroleum refinery processing a range of crude oils. This very simple definition captures a wide range of existing, emerging, and advanced process concepts. Examples of existing biorefineries include corn processors and pulp and paper mills.

The concept is analogous to a combined use of fluid catalytic cracking, ther­mal cracking, and hydrocracking technology to convert the higher-boiling-range fractions of crude oil into more useful lower-boiling-range products. Just as few petroleum refineries use all available conversion technologies, biorefineries too will use only those technology platforms that are most cost effective for converting a cer­tain type of biomass into a certain collection of desired end products. For crops and agricultural waste, it would be better to convert the biomass into bio-oil near the farm and transport the high-density bio-oil to a central facility for processing rather than transporting the low-density biomass.

The bioreflnery concept attempts to apply to biomass conversion the methods that have been applied to the refining of petroleum. The goal is to maximize the value of the products obtained from the biomass. The goal of the integrated biorefin­ery program area is to support the establishment of integrated biorefineries through partnerships with industry and academia.