about cryogenics technology

1. CRYOGENICS

2. INTRODUCTION
THE MAIN POINTS TO BE DISCUSSE ARE:
 WHAT IS CRYOGENIC TECH?
 WHAT IS THE USE OF DEWAR FLASK IN CYOGENIC?
 APPLICATIONS
 AERO SPACE IN CRYOGENIC
 HISTORY OF CRYOGENIC ROCKET ENGINE
 CRYOGENIC GRINDING
 MERITS & DEMERITS OF CRYOGENICS
 CONCLUSION

3. CRYOGENIC TECHNOLOGY
 The word ‘cryogenics’ originates from Greek word ‘Cryo’ which means
cold.
 Cryogenics is the study of very low temperature. The temperature as
low as-180 C are attained in cryogenic system.
 Cryogenics is the study of low temperature and
behaviour of material under these low temperature.
 The cryogenic process also has a unique capability for recycling difficult
to separate composite material.

4.  The extremely low temperature are produced by using
substances called ‘cryogens’. Such as Liquid Nitrogen(LN2) and
Liquid Helium(LH2).
 Liquid Nitrogen are the most commonly used in cryogenics.
 They have the boiling point of below -150 c.
 Cryogens are stored in vessels called as Dewar flask which
provides good insulation.
CONT.....

5. DEWAR FLASK

6. Liquid Nitrogen
 Nitrogen gas makes up the major portion of the atmosphere (78.03%)
by volume.
 Inert, colourless, odourless, non-corrosion, non-flammableliquid.
 Extremely cold.
 Volume of expansion liquid to gas at 15 c 1atm. i.e 1 litre of liquid
nitrogen evaporated to form 682 litres of nitrogen gas.

7. Applications of cryogenics
 Aerospace – Cryogenic Rocket Engine
 Manufacturing field
 Medical field
 Electronics field
 Fuels research

8. Aero space – Cryogenic Technology
in Rocket Propulsion
 The united states was the first country to develop cryogenic rocket
engine.
with RL – 10 engine, registered its first successful flight in 1963
and is still used on the Atlas V rocket.
 On April 15, 2010, India launched communication satellite GSAT-4
into orbit. The Geo –synchronous Satellite Launch Vehicle (GSLV).

9. Cryogenics in India

10. PROCESS FLOW

11.  Some of liquid nitrogen is utillised in cooling engine.
 Praessure of liquid nitrogen is increased from 0.7MPa to
2.9MPa using turbo pumps.
CONT.....

12. ADVANTAGES:
 High energy per unit mass.
 Economical.
DISADVANTAGES:
 Handling and storage of cryogenic gases can be
dangerous.
 Explosion.

13. MANUFACTURING FIELD – CRYOGENIC GRINDING
PROBLEMS FACED IN COVENTIONAL GRINDING
PROCESS:
 High heat generation.
 Less tool life.
 Loss of enteric oil in spice grinding.
 Oxidation.

14. Working of Cryo grinder:
 Material is to be cleaned manually fed into the
hopper.
 Liquid nitrogen from the storage container is
sprayer into screw conveyer.(i,e) conveyer
drive.
 The sensor monitor’s materials temperature in
the conveyer.
 When the mill is running the material gets
crushed between the studs &comes out through
an optional sleve as a ground product.
 To the bottom of the mill a collecting bin is
housed.
 The vaparized nitrogen from the mill is sucked
by a centrifugal blower & through the filter

15. Schematic representation of Cryo Grinder

16. Merits and De- merits:
 Merits :
 Lower grinding cost.
 Prevent oxidation.
 Finer particle size.
 No heat generation.
 De merits:
 High operation cost.
 High power consumption.

17. Health hazards of cryogenic liquids
 Skin and eye hazard: cryogens are extremely cold and can cause
instant,severe frostbite. The eye’s fluids will freeze in cantact with a
cryogens, causing permanent eye damage.
 Cold Embrittlement: at cryogenic temperatures many materials,
such as rubber, plastic and carbon steel can become so brittle that
very little stress can break the material.

18. Conclusion
 Cryogenic grinding technology can efficiently grind most tough
material and can also facilitate cryogenic recycling of tough
composite materials.
 The cryogenic process also has a unique capability for recycling
difficult to separate composite materials.