BIOREFINERIES: INTEGRATION OF DIFFERENT TECHNOLOGIES - Biomass as a Sustainable Energy Source for the Future - page 494

15.8 An EIA report (tinyurl.com/bpnnuwh) refers to four classes of liquid biofuels

as “ biomass-based biodiesel, ”“ conventional biofuels, ”“ cellulosic biofuels, ”

and “ noncellulosic advanced biofuels. ” Can you mention at least two exam-

ples of fuels per class?

15.9 In a process, ethanol is produced from corn using hydrolysis and subsequent

fermentation of the starch-derived sugar fraction. The residues are used to
feed cattle.

a. Which type of biorefinery is this?
b. Characterize the complexity using the BCI .

15.10 When biomass is pyrolyzed and the bio-oil/char mixture that is produced is
fed with heavy oil residues into a fluid catalytic cracker in an oil refinery,
is this a biorefinery?

15.11 Could an anaerobic digester also be called a biorefinery? If not, under which
conditions could it be set up as such? When manure is used as feedstock only
and biogas is produced together with digestate, what is then the BCI value?

15.12 Name examples of biorefineries that were operated already more than
100 years ago.

15.13 Name at least five different pretreatment techniques for biomass by which
fractionation of the main biomass contained polymers can be realized.

15.14 In Figure 15.4, identify what you think are major technological challenges
and discuss these in a group. Which cycles are aimed to be closed?

15.15 Why would lignin valorization to high added value products in newly
established modern biorefineries be rather a necessity than just an option?

15.16 Gonzalez et al. (2012) report on the cost of different types of equipment in a
biorefinery concept for cellulosic ethanol production using gasification. What
is the explanation for investment scale factors smaller than one? What is the
explanation for scale factors larger than one? In case of a huge scale factor,
what would you propose?

PROBLEMS

15.1 Set up two process schemes for the production of ethanol from wood, one

based on a thermochemical platform and the other based on a biochemical
platform. What are advantages and disadvantages of both schemes?

15.2 In a biorefinery concept, biomass is pretreated using organosolv so that a

cellulose stream is produced that does not dissolve in the organic solvent