This set of Fermentation Technology Multiple Choice Questions & Answers (MCQs) focuses on “Effluent – Treatment Processes”.
1. Which of the following is the method for disposal of municipal solid waste?
c) Well disposal
d) Spray irrigation
Explanation: Landfilling is the method for disposal of municipal solid waste and industrial waste. The waste is deposited into natural or manmade voids. For e.g. in disused clay pits, both solids and liquid wastes can be deposited.
2. Which of the following is not a factor to investigate in a site survey?
Explanation: The factors like BOD/COD, Colour, Radioactivity, Hardness, Odour, tastes, Turbidity, Detergents, Toxins, etc. are the important factors to investigate in a site survey.
3. Who described the disposal of antibodies and steroid wastes?
a) Colovos and Tinklenberg
b) Zajic and Melcher
d) Mbagwu and Ekwealor
Explanation: Colovos and Tinklenberg described the disposal of antibodies and steroid wastes with Biochemical Oxygen Demand of 5,000 to 20,000 dm-3. They were first chlorinated to lower the BOD and reduce unpleasant odours and then sprayed to the land until rainfall was reached.
4. Which of the following is a primary treatment?
b) Activated sludge
c) Sand filters
Explanation: Primary treatment includes physical and chemical methods like sedimentation, coagulation, etc. It will considerably reduce the Biochemical Oxygen Demand of the resulting effluent.
5. What is the function of a sedimentation tank?
a) Removal of larger suspended matter
b) Reduction in particle size
c) Removal of grit
d) Removal of finer matter
Explanation: The sedimentation tanks are used for the removal of finer matter. They are generally circular or rectangular flow tanks. They operate at retention times of 6-15 hours with the facility of continuous removal of settled sludge.
6. Which is the use of comminutors?
a) To reduce the size of particles
b) To remove the grit
c) To remove large particles
d) To remove small particles
Explanation: Sewage Grinders are also known as comminutors used in the wastewater treatment plants and pumping stations. They help in the breakdown of larger solids into the smaller ones.
7. The diameter of a conventional trickling filter is _______
a) 5-8 m
b) 5-10 m
c) 1-10 m
d) 8-16 m
Explanation: A conventional trickling filter has a diameter of 8-16 m. It consists of a cylindrical concrete tank 2-3 m in depth. Some of the filters are rectangular in shape. It is achieved mainly aerobically.
8. Who described the use of contactors in wastewater treatment?
a) Ware and Pescod
b) Arden and Lockett
c) Cooper and Wheeldon
d) Taylor and Senior
Explanation: Ware and Pescod in 1989 described the use of contactors. The full scale aerobic/anaerobic rotating biological contactors are used to remove or treat the brewery wastewaters. More than 85% of COD was removed in the aerobic stage.
9. What is the use of venturi?
a) To generate low-pressure
b) To remove grit
c) To generate high pressure
d) To break the foam
Explanation: The venturi is a system for increasing the speed of the liquid by constricting its shape. A Venturi injector is based on a fluid flow that causes low pressure at an inlet port. Thus, low-pressure can be generated from a high-pressure flow.
10. Which of the following is not the use of anaerobic treatment?
a) Achieving higher loading rates
b) Low power to treat BOD
c) The metabolization of organic matter
d) High levels of microbial growth
Explanation: There are many reasons for using anaerobic processes for waste treatment. It is useful in achieving a higher loading rate, low power BOD treatment, organic matter is metabolized into a stable form, ease of handling, low levels of microbial growth due to the anaerobic process.
11. UASB was developed in __________
Explanation: Up-Flow Anaerobic Sludge Blankets (UASB) was a system developed in the Netherlands. In this system, very high-levels of biomass is retained in the reactor by flocculation. In this, no support media is added to the reactors and it acts as a fluidized-bed.
12. Velocity channels are used to remove larger suspended particles.
Explanation: Screening is done to remove larger suspended particles and floating matter. The constant velocity channels are used to remove grit to prevent further damage to the plant in later processes. It has a velocity of 0.3 m/s.
13. Trickling filters are less suitable for a larger volume of effluents.
Explanation: The trickling filters are less suitable for a larger volume of industrial effluent because it does not have a high specific area and high voltage. Large areas are required for a larger volume of strong effluents. Towers are used as an alternative.
14. Which of the following is used where there is no oxygen supply?
b) Sedimentation tank
c) Mechanical mixer
d) Screening devices
Explanation: If there is no oxygen supply via spargers, the baffles must be provided to avoid the formation of layers. Baffles are also used to increase the rate of agitation and aeration. It is also used to provide cooling.
15. The temperature of 20°C is used to take BOD of _________
c) 5- days
Explanation: The temperature of 20°C is used to take BOD of 5 days because in 5 days the dissolved oxygen present in water is consumed for the decomposition of organic matter. Hence 5 day BOD is used as a standard to represent the amount of oxygen dissolved.
Sanfoundry Global Education & Learning Series – Fermentation Technology.
To practice all areas of Fermentation Technology, here is complete set of 1000+ Multiple Choice Questions and Answers.