Environmental Engineering

1.

Suspended solid present in the waste water generated in blast furnace gas cooling and cleaning plant is removed by

A. biological oxygen pond. B. radial settling tank (thickener) using coagulant (lime & ferrous sulphate). C. lagoons. D. filtration. 2.  Persons working in cement plants and limestone quarries are more prone to disease like A. cancer B. asthma C. silicosis D. flourosis (bone disease) 3.  Particulates (< 1μm size) remaining suspended in air indefinitely and transported by wind currents are called A. fumes B. mists C. smoke D. aerosols 4.  Operating principle of cyclone separator is based on the action of __________ dust particles. A. diffusion of B. centrifugal force on C. gravitational force on D. electrostatic force on

5.

Exposure to small amount of __________ results in high blood pressure & heart disease in human beings.

A. hydrogen sulphide B. mercury C. cadmium D. asbestos 6.  Maximum allowable concentration of CO2 in air for safe working is __________ ppm (parts per million). A. 50 B. 1000 C. 2000 D. 5000 7.  Tolerable limit of nitrogen oxides in air is __________ ppm. A. 0.1 B. 1 C. 5 D. 25 8.  Iron & manganese present as pollutant in water can not be removed by A. ion exchange process. B. oxidation followed by settling & filtration. C. lime soda process or manganese zeolite process. D. chlorination. 9.  In water chemical treatment plant, use of chloramines ensures A. disinfection. B. taste & odour control. C. weed control in reservoirs. D. removal of permanent hardness. 10.  Which of the following is the common pollutant emitted from metallurgical smelters, thermal power plant and cement plants ? A. NOx B. Hg C. SO2 D. F