Q1. Find the collecting plate area in a horizontal flow, single-stage electrostatic precipitator (ESP) handling an average gas flow of 3.1 m3/s from a pulverized coal-fired boiler. The required collection efficiency of ESP is 98%. Take drift velocity, ω = 15 cm/sec.
a. 0.189 m2
b. 64.92 m2
c. 80.85 m2
d. 94.54 m2
Answer:- c. 80.85 m2
Q2. A baghouse filter is having 30 compartments, 220 bags per compartment, and each bag of diameter 12 m and bag length 25 m, with a gas flow rate of 1,500,000 m3/min. Calculate the gross air to cloth ratios.
- 0.00241 m/min
- 0.0241 m/min
- 0.241 m/min
- 2.411 m/min
Q3. Calculate the amount of calcium hydroxide (lime) needed to neutralize the HCl (Hydrochloric acid) absorbed from a gas stream having 30 ppm HCl and a flow rate of 15,000 SCFM (Standard Cubic Feet per Minute). Assume an HCl removal efficiency of 98%.
- 0.04 lb/hr
- 1.01 lb/hr
- 2.54 lb/hr
- 9.6 lb/hr
Q4. What is the maximum toluene removal efficiency possible in a refrigeration-type condenser operating at -125°F if the inlet concentration is 21,000 ppm? Given the outlet partial pressure @ -125°F for toluene is 0.018 mm Hg.
- 88.58 %
- 90.66 %
- 98.87 %
- 99.88 %
Q5. According to the recently published WHO air quality guidelines, 2021, the permissible limit of SO2 (in µg/m3) is given as:
Q6. Which of the following pollutants is not included in the revised National Ambient Air Quality Standard (NAAQS, 2009):
Q7. Which of the following Acts is considered as the first act/regulation enacted to address the issue of air pollution:
Q8. According to the notification for e –vehicles for NCR in 2022, the Transport Department, Government of NCT of Delhi is directed to ensure that all the aggregators and delivery service providers should adopt electric vehicles (two-wheelers) in the proportion of ______ within 31st March 2023.
Q9. Ministry of Road Transport and Highways (MoRTH) decided to move directly from ____________emission standards by 2020
Q10. National Clean Air Programme (NCAP) launched in 2019 targets to reduce 20 % – 30 % of PM2.5 and PM10 concentration by 2024, keeping ______ as the base year for the comparison of concentration.