(246n) Vcap: A Software Platform for the Assessment of Biorefinery Value Chains

In this work, we present VCAP (Value Chain Assessment Platform), a platform that facilitates the assessment of biorefinery value chains. VCAP combines a user friendly interface and an optimisation algorithm into a web service that is easy to use.

Current implementation facilitates the consideration of softwood and agricultural residues as the biomass input. It also facilitates consideration of a range of products including cellulose, hemicellulose in the form of sugars, and lignin. Current implementation only considers a sonication technology. That technology can be described in the following steps:

1. the feedstock is mixed with an organic acid solution to form a slurry
2. organic solvents are added to form an organosolv slurry prior to sonication
3. after sonication the solid and liquid are separated and the dried solid contributes toward the cellulose fraction
4. the liquid is further separated into the organic and aqueous fraction via water addition
5. the organic fraction contains lignin and some organic solvent, and the aqueous fraction contains the hemicellulosic sugars, the remainder of the organic solvent, and the water and acid.
6. lignin and hemicellulose are isolated via membrane or distillation technology and the organic acidic water and solvents are recycled

The optimisation algorithm employed by the platform takes into account various steps of the value chain from the collection of biomass and its transportation to different biorefining technologies and end products and assesses the economic potential of different types of biomass and/or biorefinery technologies in various geo-economic environments. As at present, VCAP can be adapted to account for any number and type of lignocellulosic biomass (e.g. hardwood, softwood, wheat straw, grasses etc.), and optimises under three different scenarios (supply, demand and biorefinery facility).

In an effort to increase the flexibility of the platform, the technology (biorefinery) module is substitutable, allowing the consideration of different technology models. VCAP also features links to external databases extracting information about biomass availability, composition and prices. Also, a mapping solution is employed to allow for a more dynamic and friendly interaction with users, regardless of the level of their expertise. The platform, developed in Java and using GLPK solver for the Mixed Integer Linear Programming problem, has been validated with a case study in Scotland.

More specifically, three scenarios have been taken into account for the case study: i) Supply-driven, ii) Demand-driven and iii) Technology-driven. The biomass type considered in all three scenarios was softwood in the form of logs and chips (sawmill by-products). The moisture contents of the selected biomass types range between 30% - 60%. Finally, candidate points for technologies were located close to power stations in order to utilise the waste heat energy.