This set of Hazardous Waste Management Multiple Choice Questions & Answers (MCQs) focuses on “Aerobic Systems”.
1. What is the minimum oxygen requirement to promote growth of aerobic bacteria?
a) 0.2 ppm
b) 0.3 ppm
c) 0.4 ppm
d) 0.5 ppm
Explanation: Minimum requirement of 0.5 ppm free dissolved oxygen is essential to promote growth of aerobic bacteria.
2. The temperature range for aerobic process is _____ degree Celsius.
Explanation: The temperature range for aerobic process is 10-30 degree Celsius i.e. the psychrophilic range.
3. The concentration of microorganisms in the digestion tank is measured as ____
Explanation: Microorganisms concentration in the digestion tank is measured as mixed liquor suspended solids (MLSS) or volatile suspended solids (VLS).
4. Which of the following is function of the MLSS content of the hazardous waste liquor?
a) BOD loading
b) COD loading
c) MLSS loading
d) VLS loading
Explanation: The BOD loading on biological system in terms of kg BOD/m3 of reactor volume/day is function of the MLSS content of the hazardous waste liquor.
5. Higher loading level increase BOD removal efficiency. True or False.
Explanation: Higher loading rate decrease BOD removal efficiency, increase sludge production and induce sludge bulking in the system.
6. What is the organic loading rate in aerobic fixed culture systems?
a) 1-9 kg BOD/m3
b) 1-7 kg BOD/m3
c) 1-8 kg BOD/m3
d) 1-5 kg BOD/m3
Explanation: Organic loading rate in aerobic fixed culture systems vary from 1–8 kg BOD/m3 tower volume/day.
7. What is the average retention time in aerobic treatment system?
a) 20 minutes
b) 10 minutes
c) 30 minutes
d) 40 minutes
Explanation: Average retention times in aerobic systems range from 20 minutes in biological filters to 24 hours in activated sludge plants.
8. In aerobic treatment, microbes need carbon source. True or False.
Explanation: In aerobic treatment, microbes need carbon and energy source to oxidize hazardous waste and nutrients such as nitrogen, phosphorus and trace metals are also utilized.
9. _____ is required for complete mineralization of hazardous waste.
a) Metabolic interaction
b) Chemical analysis
d) Toxic removal
Explanation: Metabolic interaction among groups of microorganism is required for complete mineralization of hazardous waste.
Sanfoundry Global Education & Learning Series – Hazardous Waste Management.
To practice all areas of Hazardous Waste Management, here is complete set of 1000+ Multiple Choice Questions and Answers.