CPWM Waste Treatment Technologies 5

Question 1

What is the primary purpose of the SNCR (Selective Non-Catalytic Reduction) system in a waste-to-energy plant?

Accepted Answer

Reduce NOx emissions by injecting ammonia or urea into the furnace

Answer

SNCR reduces nitrogen oxides (NOx) by injecting ammonia or urea into the high-temperature furnace zone (850–1100°C), where reagents react with NOx to form nitrogen gas and water without a catalyst.

Question 2

Which treatment technology converts the organic fraction of municipal solid waste into a soil amendment through controlled biological decomposition?

Accepted Answer

All of the above can produce a soil amendment

Answer

All three approaches — MBT, anaerobic digestion with digestate composting, and source-separated organics composting — can produce stabilized organic soil amendments when properly designed and operated.

Question 3

Under RCRA, which treatment standard applies to hazardous debris (contaminated equipment, containers, or soil) before land disposal?

Accepted Answer

Debris-specific standards allowing extraction or destruction technologies

Answer

RCRA's debris rule (40 CFR §268.45) allows hazardous debris to meet LDR standards through extraction technologies (washing, thermal desorption) or destruction/immobilization technologies specific to debris rather than UTS concentration levels.

Question 4

What is the function of a refuse-derived fuel (RDF) system in integrated waste management?

Accepted Answer

Process MSW to remove non-combustibles and produce a high-energy fuel pellet or fluff

Answer

RDF systems shred, screen, and separate MSW to remove metals, glass, and inerts, producing a combustible fraction (pellets or fluff) with higher and more consistent energy content than raw MSW.

Question 5

Which chemical oxidation reagent is most commonly used for in situ chemical oxidation (ISCO) of chlorinated solvents in groundwater?

Accepted Answer

Potassium permanganate

Answer

Potassium permanganate (KMnO₄) is widely used in ISCO for chlorinated solvents (PCE, TCE) due to its stability, long persistence in the subsurface, and effective oxidation of the C=C double bond.

(CPWM) Certified Professional in Waste Management Practice Test

(CPWM) Certified Professional in Waste Management Practice Test

CPWM Waste Treatment Technologies 5