Biomass in Alberta Province of Canada - Coursework Example

Download file to see previous pages The major sources of biomass in Canada are agriculture, food-processing residues, industrial wastes, municipal sewage, and household garbage (Cruickshank, Robert, & Silverside, 2011). However, in the Alberta province, the major sources of biomass are listed in the Table below. Switchgrass is currently used for the production of biofuel (Jefferson, McCaughey, May, Woosaree, & McFarlane, 2002).

The following bio-products can be obtained from the bio-refinery: bio-diesel, ethanol, modified proteins, adhesives and resins, solvents and lubricants as well as industrial plant-based oil products (such as fertilizers, plastics), and plant-made industrial products (such as composites),
Propose conversion technologies that can be applied in the biorefinery to produce the identified products; at least two different paths to ethanol should be included
Biomass handling technologies for the production of different bio-products from the biomass listed in the Table above-involved harvesting, transportation, storage, pre-processing, and fermentation or anaerobic digestion.

Pretreatment is carried out by hydrolysis of lignocellulosic material with dilute sulphuric acid (0.7-5% v/v) in two stages to yield fermentable sugars such as D-glucose, D-mannose, D-galactose, L-rhamnose, D-xylose, L-arabinose, and uronic acids. The first stage is carried out at 140 °C for 15 min to hydrolyze the hemicelluloses and the second stage proceeds at 190 °C for 10 min to break down the cellulose. Any residue cellulose is hydrolyzed enzymatic ally.
The bioconversion of D-xylose into ethanol from hemicellulosic materials is limited by the presence of toxic compounds, such as phenol, furfural, 5-hydroxymethylfurfural and acetic acid. These toxic compounds decrease bioprocess productivity. The toxic compounds are removed by use first adjusting the pH to 9-10 by using Ca(OH)2 to facilitate the removal of the toxic compounds and this is followed by readjusting the pH back to 5. The hydrolyzed hemicellulosic material will be fermented with S. cerevisiae for ethanol production.

Alternatively, ethanol can be obtained from the biomass by carrying the pretreatment process using steam explosion at 160-290 °C, 0.7-5 MPa. The process depolymerizes the cellulose and the hemicellulosic materials. Detoxification and fermentation processes as described above are carried out to yield ethanol.
For each possible path, estimate how much ethanol can be produced per year. Use theoretical yield if the actual conversion efficiency is unknown.

Theoretical yield
The percentage of cellulose in Switchgrass is 40.2% (Jefferson, McCaughey, May, Woosaree, & McFarlane, 2002)
Percentage of hemicelluloses in Switchgrass = 32.5% (Jefferson, McCaughey, May, Woosaree, & McFarlane, 2002)
Hydrolysis of 1 kg C6 sugar polymers gives 1.11 kg monomer sugars
Hydrolysis of 1 kg C5 sugar polymers gives 1.14 kg monomer sugars
Fermentation of 1 kg glucose (C6) gives 0.511 kg ethanol
Theoretical yield = ([(40.2 *1.11) + (32.5*1.14)] * 0.51)
Theoretical yield = 41.65/100 = 0.42 kg/kg feed = 0.55 L/kg feed

Comment on the logistic aspect (mainly the transportation of feedstock) of the biorefinery, taking into account the scale of operation, the distribution of feedstock, and the means of transportation
The transportation of the feedstock may be costly and will require trunks. This will increase the cost of production of ethanol. ...Download file to see next pages Read More