Wet sieving is employed, when the product contains ________________ materials?

Related Mcqs:

1. Mixing mechanism employed in a pan mixer is by ________________?

   A. Mulling
   B. Kneading
   C. Dispersion
   D. None of these

2. Work index is the gross energy (kWh/tonne of feed) necessary to reduce a very large feed to such a size that 80% of product particles will pass through a 0.1 mm screen. The value of work index determined for wet grinding should be multiplied with ______________ to get the same for dry grinding?

   A. 1.0
   B. 0.5
   C. 1.34
   D. 4.34

3. In coal washeries, three products namely the valuable product (i.e. clean/washed coal), discarded product (i.e. mineral matter) and an additional concentrated product called _____________ is produced?

   A. Concentrate
   B. Tailing
   C. Middling
   D. None of these

4. In case of a revolving mill, wet grinding compared to dry grinding__________________?

   A. Requires more energy
   B. Has less capacity
   C. Complicates handling & classification of the product
   D. None of these

5. Which of the following is not a wet classifier ?

   A. Sharpies super-centrifuge
   B. Hydrocyclones
   C. Dorr Oliver rake classifier
   D. None of these

6. Wet grinding in a revolving mill ______________ as compared to dry grinding ?

   A. Gives less wear on chamber walls
   B. Requires more energy
   C. Increases capacity
   D. Complicates handling of the product

7. Rod mills employed for grinding_________________?

   A. Employ a steel shell having L/D ratio of 1.5 to 3.0
   B. Is useful for handling sticky materials
   C. Employ steel rods of 2-12 cms diameter extending over full length of the mill
   D. All A , B & C

8. In a size reduction crushing operation, feed size is 300 to 1500 mm while the product size is 100 to 300 mm. This is a case of the ________________ crushing?

   A. Secondary
   B. Fine
   C. Primary
   D. Ultrafine

9. Bucket elevators are not suitable for the vertical lifting of __________ materials?

   A. Fine (e.g. – 200 mesh size coal)
   B. Sticky (e.g. clay paste)
   C. Small lumpy (e.g. grains and sand)
   D. Free flowing

10. Which of the following conveyors cannot be recommended for transportation of abrasive materials ?

    A. Belt conveyor
    B. Apron conveyor
    C. Flight conveyor
    D. Chain conveyor