Week 7 Assignment 7. The due date for submitting this assignment has passed NPTEL - Privacy & Terms - Honor Code - FAQs - Funded by

Transcription

1 X Courses» Introduction to Mineral Processing Unit 8 - Announcements Course Ask a Question Progress Mentor Course outline How to access the portal Assignment 7 The due date for submitting this assignment has passed. Submitted assignment Due on , 23:59 IST. Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Lecture 35: Movement of Lecture 36: Movement of Lecture 37: Movements of Lecture 38: Classifier Lecture 39: Classifier Feedback for Lecture Material A project Quiz of : Assignment 7 1) A particle of 1 mm in diameter and density of 2500 kg/m3 is settling in a stagnant fluid in the Stokes flow regime. Calculate the viscosity (Pa.s) of the fluid if the fluid density is 1000 Kg/m3 and the particle falls at a terminal velocity of 2mm/s ) Use Stoke s Law to calculate the terminal settling velocity(m/s) of a particle of diameter 0.01 mm in a fluid having density 1000 kg/m3 and viscosity Pa.s. The density of particle is 2650 kg/m * * * * *10-5 3) Consider a binary mixture of quartz (specific gravity 2.60) and galena (specific gravity 7.5) particles being classified in water at 40 C. Determine the free-settling ratio between quartz and galena using Newton s law NPTEL - Privacy & Terms - Honor Code - FAQs In association with 5.94 Assignment 7_Solution 4.1 Funded by 1 of 5 Tuesday 15 May :30 AM

2 Week 8 Week 9 Week 10 Week 11 Week 12 DOWNLOAD VIDEOS Powered by 4.1 4) The ratio of sizes of equally falling particles in a fluid medium is called Reduction ratio Settling ratio Steeling ratio Settling ratio 5) When the particle seperation is carried out in a fluid medium based on the difference on their sizes, the technique is termed as. Classification Elutriation Clarification Classification 6) If a force greater than that of gravity is used to separate solids & fluids of different densities, the process is termed as the Centrifugation Dispersion Flocculation Centrifugation 7) The rate of hindered settling is More than that of free settling Less than that of free settling Equal to that of free settling Less than that of free settling 8) Under otherwise uniform conditions, Hindered settling is More effective than free settling in separation of substances 2 of 5 Tuesday 15 May :30 AM

3 Less effective than free settling in separation of substances As effective as free settling in separation of substances More effective than free settling in separation of substances 9) Sorting classifiers are devices which separate particles having Different densities Different molecular weight Different surface area per unit volume, but same density Different magnetic properties Different densities 10) The liquid used as sorting medium in the differential settling method should have a density Higher than that of either substance Lower than that of either substance Which is intermediate between densities of the light and heavy substance Lower than that of either substance 11) If the fluid flow and particle settling directions are opposite, the classification is called? Counter flow Both Counter flow 12) All wet classifiers work on the principle of the difference in settling velocity of particles True False Can not say True 3 of 5 Tuesday 15 May :30 AM

4 13) In a sedimentation experiment, the thickened slurry is withdrawn from. Bottom Top Sideways Blow off Bottom 14) Two particles are called to be equal settling, if they are having the same. Specific gravity Size Terminal velocities in the same fluid and in the same field of force Terminal velocities in the same fluid and in the same field of force 15) Determine the settling rates (m/sec) of 40 μm size spherical quartz particles in stagnant water using Newton s Law. The density of quartz and water are 2650 kg/m3 and 1000 kg/m3 respectively and viscosity of water is Pa.s. 4.41* 10^(-2) 3.41* 10^(-1) 0.41* 10^(-1) 1.43* 10^(-3) 4.41* 10^(-2) Previous Page End 4 of 5 Tuesday 15 May :30 AM

5 5 of 5 Tuesday 15 May :30 AM