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BIOREFINERY PLATFORMS



IEA Bioenergy Task 42 has developed a classification scheme to describe different biorefineries. The classification of a biorefinery consists of the following features: platforms, feedstocks, products and processes. With the combination of these features, different biorefinery configurations can be described and named in a consistent manner. The most important feature is the platform. Platforms are intermediates which link feedstocks and final products. The platform concept is similar to that used in the petrochemical industry, where the crude oil is fractionated into a large number of intermediates that are further processed to final energy and chemical products. The platforms are recognized as the main pillars of this biorefinery classification, since they might be reached via different conversion processes applied to various raw materials. 
In this section, you can find for each platform: a short description of its main characteristics and links related to this platform from this blog and other interesting resources. 

1. SYNGAS PLATFORM
Synthesis gas (syngas) is a mixture of mainly carbon monoxide and hydrogen. It is produced by subjecting biomass to thermal degradation in the presence of an externally supplied oxidizing agent (air, steam or oxygen) in a process known as gasification. After cleaning, the syngas can be used to produce power or can be converted into alcohols, fuel and chemical products. Syngas can also be fermented to give methanol, ethanol, ammonia and other chemical building blocks.
LABEL: SYNGAS PLATFORM.
Blog post - Review (only in Spanish): BIOMASS TO LIQUID (1ª Parte / 2ª Parte / 3ª Parte).

2. PYROLYSIS OIL PLATFORM
Biomass pyrolysis is its thermal decomposition in the absence of oxygen to produce liquid, char and gas. The bio-oil or pyrolysis oil is the liquid fraction. A biorefinery based on pyrolysis oil is designed much like a traditional refinery. Bio-oil can be divided into different fractions and each fraction can be upgraded with a different technology to finally derive the optimal combination of high value and low value products. 
LABEL: PYROLYSIS OIL PLATFORM.
Blog post - Review (only in Spanish): BIO-OIL (1ª Parte 2ª Parte / 3ª Parte).

3. SUGAR PLATFORM
Six carbon sugar platform (glucose, fructose, galactose,…) can be accessed through hydrolysis of sucrose, starch, cellulose and hemicellulose. C6 sugars serve as feedstock for biological fermentation processes providing access to a variety of important chemical building blocks. They can also be converted by chemical processing. Mixed six and five carbon platform are produced from the hydrolysis of hemicelluloses. The fermentation of these carbohydrate streams can in theory produce the same products as six carbon sugar streams. 
LABEL: SUGARS PLATFORM.
Final report for the European Commission: From the Sugar Platform to biofuels and biochemicals.

4. OIL PLATFORM
As a chemical feedstock, the triacylglycerol molecule (from oilseed crops, algae and oil based residues) is either cleaved to glycerol and fatty acids or converted to alkyl esters and glycerol by transesterification. The fatty acid derivatives are used as surface active agents in personal care products, alkyd resins, biolubricants, building blocks for bio-based plastics… Glycerol is also an important co-product. The new supply of glycerol has encouraged chemical producers to look at technology for its conversion to chemical building blocks. 
LABEL: OIL PLATFORM.

5. PLATAFORMA DE BIOGÁS
Biogas production is mainly based on the anaerobic digestion of biomass with high content of moisture: manure, waste streams from food processing plants…). Anaerobic digestion results in the formation of methane, that is typically scrubbed and used for its energetic value, and solid and liquid digestate. Biogas production can be part of integrated biorefinery concepts as it can derive value from wet streams. 
LABEL: BIOGAS PLATFORM.

6. ORGANIC SOLUTIONS PLATFORM
First processing of fresh wet biomass (grass, alfalfa, immature cereals,…) involves dewatering to obtain two separate intermediates: a nutrient-rich juice organic solution and a fibre-rich lignocellulosic press cake. Both intermediates are starting points for various valorization pathways. The organic solution can contain valuable compounds: carbohydrates, proteins, free amino acids, organic acids, minerals, hormones and enzymes. The press cake fibres can be utilized as green feed pellets, processed to fibre products or potentially used as raw material for other platforms. 
LABEL: GREEN BIOREFINERY.

7. LIGNIN PLATFORM
Lignin is an extremely abundant raw material contributing as much as 30% of the weight and 40% of the energy content of lignocellulosic biomass. High-purity lignin can be converted in various high-value chemicals, among which are BTX (Benzene, Toluene, Xylene), phenol, vanillin or carbon fibre. 
LABEL: LIGNIN.

8. HYDROGEN PLATFORM
Biohydrogen can be obtained from water-gas shift reaction, steam reforming, water electrolysis and fermentation. It might be used either as an energy or as a raw material.  

9. POWER AND HEAT
Power and heat can be internally used to meet the energy needs of the biorefinery or sold to the grid. 

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REFERENCES
1 “Bio-Based Chemicals: Value Added Products from Biorefineries”. IEA Bioenergy, Task 42 Biorefinery.
2 F Cherubini et al.: “Toward a common classification approach for biorefinery systems”. Published online in Wiley InterScience (www.interscience.wiley.com); DOI: 10.1002/bbb.172; Biofuels, Bioprod. Bioref. (2009).

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