GTU BE 8th Semester 2183613 Engineering of Pigmented Dispersion Summer 2018 Question Paper

1

Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE – SEMESTER ?VIII (NEW) – EXAMINATION ? SUMMER 2018
Subject Code: 2183613 Date: 02/05/2018
Subject Name: Engineering of Pigmented Dispersion
Time: 10:30 AM to 01:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.

MARKS

Q.1 (a) Discuss the concept of pigment dispersion. 03
(b) Elaborate the adhesion & cohesion phenomenon associated with
dispersion.
04
(c) Explain the rate of penetration of liquid by using wash-burn
equation.
07

Q.2 (a) Write a note on Planetary Mixer 03
(b) Discuss about underlying fluid mechanics, mill base rheology of high
speed mixer.
04
(c) Explain the working principle & operation of Pug mixer. 07
OR
(c) Explain the different impeller geometries & orientations of high speed
mixer.
07
Q.3 (a) Write down the working principle of two roll mill. 03
(b) Discuss about batch & continuous operation of ball mill. 04
(c) Explain the phenomenon of cascading of ball mill with respect to
change in rotational speed of ball mill.
07
OR
Q.3 (a) How do you analyze the fineness of dispersion? 03
(b) Explain the triple roll mill with its principle. 04
(c) Derive the equation with respect to power consumption in ball
mill.
07
Q.4 (a) Write the mechanism of attrition. 03
(b) Discuss about stability of micro bead dispersion. 04
(c) Explain the micro bead mill with respect to various types of mills. 07
OR
Q.4 (a) How do you compare attritor with respect to ball mill. 03
(b) Discuss the pigment size and size distribution, nature of premix
processing of micro bead mill.
04
(c) Explain the effect of retention time/ flow rate, grinding media
size, shape & composition on micro-bead mill.
07
Q.5 (a) Elaborate the term combustible dust and combustible solid
particulate.
03
(b) Discuss the secondary explosion mechanism. 04
(c) Explain in detail the various factors are responsible for
combustible dust explosion.
07
OR

Q.5 (a) Write a note on: Minimum explosive concentration. 03
(b) Discuss about the hazards analysis. 04
(c) Explain the various factors should consider for preventing
explosion.
07
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