Environmental Engineering in CE Which of the following is the most active zone of atmosphere in which weathering events like rain, storm & lightning occur? Troposphere Stratosphere None of these Thermosphere Troposphere Stratosphere None of these Thermosphere ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is __________ decibels. 75 105 95 35 75 105 95 35 ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE The disinfection efficiency of chlorine increases by(i) Decreasing the time of contact(ii) Decreasing the temperature of water(iii) Increasing the temperature of water Only (i) Both (i) and (ii) Only (iii) Both (i) and (iii) Only (i) Both (i) and (ii) Only (iii) Both (i) and (iii) ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Coal mines drainage waste water (acidic in nature) results from the earth's water percolating through the voids created in coal bed during mining. This polluted water which either drains out naturally to water courses or are removed before starting the mining is Diluted with fresh water to reduce its acidity Neutralised by alkali treatment None of these Left as such without any treatment Diluted with fresh water to reduce its acidity Neutralised by alkali treatment None of these Left as such without any treatment ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Scale formation in boiler is controlled by Eliminating H₂S in feed water Reduction in hardness, silica & alumina in feed water Keeping the pH value of feed water just below 7 Preheating of feed water Eliminating H₂S in feed water Reduction in hardness, silica & alumina in feed water Keeping the pH value of feed water just below 7 Preheating of feed water ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE The main pollutant in waste water discharged from a petroleum refinery is oil (both in free and emulsified form). Free oil is removed by Aerated lagoons Trickling filters Gravity separator having oil skimming devices Biological oxygen pond Aerated lagoons Trickling filters Gravity separator having oil skimming devices Biological oxygen pond ANSWER DOWNLOAD EXAMIANS APP