MCQOPTIONS
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MCQOPTIONS
This section includes 14 Mcqs, each offering curated multiple-choice questions to sharpen your Energy Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
What is the main disadvantage of race and ball mill pulverizer? |
| A. | Mill requires extra floor area |
| B. | It is directly connected to the motor |
| C. | High power consumption |
| D. | Greater wear |
| Answer» E. | |
| 2. |
What happens due to the pressure in the pulverizer? |
| A. | Pulverized fuel is blown into boiler room |
| B. | Increases the rate of combustion |
| C. | Makes the process is vigorous |
| D. | The large particles in the pulverized fuels are removed out |
| Answer» B. Increases the rate of combustion | |
| 3. |
What is done when there is requirement for more coal in the ball and race mill? |
| A. | The primary air flow is increased |
| B. | The combustion intensity is reduced |
| C. | The secondary air flow sucks out the light coal particles |
| D. | The hopper is fully opened |
| Answer» B. The combustion intensity is reduced | |
| 4. |
Why are heavy impurities provided in the process of ball and race mill? |
| A. | To resist upward thrust caused by secondary air stream |
| B. | To resist downward thrust caused by primary air stream |
| C. | To resist upward thrust caused by primary air stream |
| D. | To resist downward thrust caused by secondary air stream |
| Answer» D. To resist downward thrust caused by secondary air stream | |
| 5. |
What is the purpose of fixed vanes in the ball and race mill? |
| A. | Forms a cyclonic flow |
| B. | For easy movement of the coal |
| C. | For directing the airflow |
| D. | For barring the exhaust air to enter back into mill |
| Answer» B. For easy movement of the coal | |
| 6. |
Which type of fan is used in the ball and race mill? |
| A. | Forced draught fan |
| B. | Balanced draught fan |
| C. | Artificial draught fan |
| D. | Natural draught fan |
| Answer» B. Balanced draught fan | |
| 7. |
What type of feeder is used to supply the coal in ball and race mill? |
| A. | Ring main feeder |
| B. | Parallel feeder |
| C. | Radial feeder |
| D. | Rotating table feeder |
| Answer» E. | |
| 8. |
The pulverization is completed by a combination of crushing impact and _______ between grinding surfaces. |
| A. | Accretion |
| B. | Erosion |
| C. | Attrition |
| D. | Dissolution |
| Answer» D. Dissolution | |
| 9. |
Why ball and race mill is also called as contact mill? |
| A. | Because of rolling action between the balls and races |
| B. | Because of ramming action between balls and races |
| C. | Because of swirling action of balls and races |
| D. | Because of mixture of balls and races |
| Answer» B. Because of ramming action between balls and races | |
| 10. |
What is the pulverization capacity of the ball mill? |
| A. | 10 tons of coal per hour |
| B. | 20 tons of coal per hour |
| C. | 50 tons of coal per hour |
| D. | 80 tons of coal per hour |
| Answer» B. 20 tons of coal per hour | |
| 11. |
Feeder output in cylinder of a ball mill is regulated on the basis of? |
| A. | Cylinder capacity |
| B. | No of balls |
| C. | Level of coal |
| D. | Rotation speed of cylinder |
| Answer» D. Rotation speed of cylinder | |
| 12. |
The output of the mill can be controlled by the _________ located in the exhaust fan inlet duct. |
| A. | Dampers |
| B. | Blowers |
| C. | Air duct |
| D. | Ventilator’s |
| Answer» B. Blowers | |
| 13. |
Why pre-heater air and the tempered air are introduced in the pulverizer of ball mill? |
| A. | To carry the ash out |
| B. | To increase the combustion rate |
| C. | To carry pulverized coal |
| D. | To dry the coal by removing the moisture |
| Answer» D. To dry the coal by removing the moisture | |
| 14. |
How is coal pulverized in the ball mill? |
| A. | By rotating the cylinder |
| B. | By rolling the cylinder |
| C. | By hammering the cylinder |
| D. | By jolting the cylinder |
| Answer» B. By rolling the cylinder | |