A. Biological oxygen pond
B. Radial settling tank (thickener) using coagulant (lime & ferrous sulphate)
C. Lagoons
D. Filtration
Related Mcqs:
- Phenolic water generated in coke ovens & by-product plant attached to an integrated steel plant containing phenol in concentration of less than 100 mg/litre can be removed by_______________?
A. Chlorination
B. Treating in biological oxygen pond
C. Chemical coagulation
D. None of these - Coal washing waste water containing about 3% suspended solids (comprising of clay, slate, stone etc.) is treated for solid particles removal ?
A. By chemical coagulation
B. In sedimentation tanks equipped with mechanical scrapper
C. In vacuum filter
D. In clarifiers - Waste/polluted water discharged from electroplating, blast furnace and coal mining industries contain mainly _____________ substances?
A. Radioactive
B. Organic
C. Inorganic
D. None of these - Iron & manganese present as pollutant in water cannot be removed by__________________?
A. Ion exchange process
B. Oxidation followed by settling & filtration
C. Lime soda process or manganese zeolite process
D. Chlorination - Phenolic water generated in coke ovens & by-product plant of a steel plant are disposed off by_________________?
A. Quenching of hot coke
B. Discharging in the river stream
C. Filtration and recycling for cooling coke oven gas
D. None of these - Thermal pollution of water increases its toxicity and oxidation of oxygen demanding waste besides favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of _____________ present in it?
A. Coal ash
B. Potassium cyanide
C. Ortho-xylene
D. None of these - The main pollutant in waste water discharged from a petroleum refinery is oil (both in free and emulsified form). Free oil is removed by_________________?
A. Biological oxygen pond
B. Aerated lagoons
C. Trickling filters
D. Gravity separator having oil skimming devices - Which is the most efficient dust removal equipment for removal of submicronic dust particles from blast furnace gas ?
A. Packed scrubber
B. Gravity settling chamber
C. Electrostatic precipitator
D. Hydrocyclone - Which is the most practical and economical method for removal of suspended solid matter from polluted water ?
A. Sedimentation
B. Skimming off
C. Chlorination
D. Biological oxidation - Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan_________________?
A. With greater number of blades
B. Of increased diameter
C. Both A. & B.
D. Neither A. nor B.
