May 2007, Vol. 19, No.5
Test Your Knowledge of Fats, Oil, and Grease
True or False Questions:
- If excessive levels of FOG enter a secondary treatment system, the low-density FOG constituents merge with the biomass.
- FOG sample containers should not be rinsed with solvent before analysis.
- In the lab, FOG samples can be split easily for multiple analyses.
- A wastewater treatment plant designed to treat typical components of domestic wastewater also will provide the hydraulic and solids retention times necessary to remove effectively high levels of FOG.
Multiple Choice Questions:
What are the typical characteristics of FOG from animal sources?
A. Polar and biodegradable.
B. Nonpolar and biodegradable.
C. Polar and nonbiodegradable.
D. Nonpolar and nonbiodegradable
What happens to petroleum-based oil in a mixed and heated anaerobic digester?
A. The oil degrades, and the metabolites settle into the solids.
B. The oil collects into a slick that floats on top of the digester contents.
C. The oil mixes with the supernatant and recycles back to the head of the plant with it.
D. The oil adheres to the solids and passes out of the digester with them.
In an activated sludge plant, where is most floatable FOG removed?
B. Primary clarifiers.
C. Secondary clarifiers.
D. Tertiary treatment.
Match the discharger with the type of FOG it is most likely to discharge. Use A for animal, P for petroleum, and V for vegetable.
A. ___ Milk processing
B. ___ Candy manufacturing.
C. ___ Metal machining.
D. ___ Tanneries.
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Questions were developed by Steve Spicer and reviewed by the Association of Boards of Certification (Ames, Iowa) Validation and Examination Committee.
Water Environment Federation (1996). Operation of Municipal Wastewater Treatment Plants; Manual of Practice No. 11, Fifth Ed. Alexandria, Va.: Water Environment Federation.