REP Bioenergy and Waste-to-Energy 2

Question 1

Which gasification agent produces the highest heating value syngas but is too costly for most commercial waste-to-energy applications?

Accepted Answer

Pure oxygen

Answer

Pure oxygen gasification produces high-quality syngas with minimal nitrogen dilution but is economically prohibitive for most commercial WtE projects.

Question 2

The Fischer-Tropsch process converts syngas into liquid fuels primarily through which reaction type?

Accepted Answer

Catalytic hydrogenation of CO and H2

Answer

Fischer-Tropsch synthesis uses catalysts to polymerize CO and H2 into liquid hydrocarbons ranging from diesel to waxes.

Question 3

In a biomass integrated gasification combined cycle (BIGCC) plant, what is the primary efficiency advantage over conventional steam-only biomass power?

Accepted Answer

Use of gas turbine topping cycle before steam recovery

Answer

BIGCC achieves higher electrical efficiency by extracting work from a gas turbine first, then recovering exhaust heat in a steam cycle.

Question 4

Which municipal solid waste fraction typically has the highest energy content on a dry weight basis?

Accepted Answer

Plastics

Answer

Plastics have a high calorific value (~35–45 MJ/kg dry) derived from their hydrocarbon polymer chains, exceeding most other MSW components.

Question 5

What does the term 'refuse-derived fuel (RDF)' specifically refer to?

Accepted Answer

Processed and shredded MSW with non-combustibles removed for fuel use

Answer

RDF is MSW that has been mechanically processed—shredded, screened, and separated—to remove non-combustibles and improve fuel consistency.

(REP) Certified Renewable Energy Professional Practice Test

(REP) Certified Renewable Energy Professional Practice Test

REP Bioenergy and Waste-to-Energy 2