PRESENTED BY :-SATYA PRAKASH PANDEY

NUCLEAR REACTOR

IT IS THE APPARATUS IN WHICH NUCLEAR FISSION IS PRODUCED IN THE FORMOF A CONTROLLED SELF-SUSTAINING CHAIN REACTION.

GAS COOLED REACTOR DEFINITION

GAS COOLED REACTOR IS A NUCLEAR REACTOR WHICH USES GRAPHITE AS MODERATOR AND GAS AS COOLANT .

COOLANT GAS USED MAY BE CARBON DIOXIDE OR HELIUM.

TYPES OF GAS COOLED REACTOR

THERE ARE TWO TYPES OF GAS COOLED REACTOR :-

1. GAS COOLED GRAPHITE MODERATOR REACTOR (GCGM)

2. HIGH TEMPERATURE GAS COOLED REACTOR ( HTGC)

GAS COOLED GRAPHITE MODERATOR REACTOR

IT USES GRAPHITE AS MODERATOR AND NATURAL URANIUM AS FUEL .

GENERALLY GENERATION OF GAS COOLED GRAPHITE MODERATOR REACTORCOMPRISES OF TWO TYPES OF GENERATION :-

1. MAGNOX REACTOR INVENTED BY BRITAIN2. UNGG REACTOR INVENTED BY FRANCE

COOLANT PRESSURE AND TEMPERATURE IN GCGM IS ABOUT 7 bar 336 degree C .

GAS COOLED GRAPHITE MODERATOR REACTOR

HIGH TEMPERATURE GAS COOLED REACTOR

HTGC COMPOSED OF URANIUM CARBIDE MIXED WITH THORIUM CARBIDE CLADDED WITH GRAPHITE.

COOLANT PRESSURE AND TEMPERATURE IN HTGC IS ABOUT 15 bar to 30 bar 700 degree C TO 800 degree C .

ADVANTAGES OF GAS COOLED REACTOR

1. PROCESSING OF FUEL IS SIMPLER.

2. NO CORROSION PROBLEM .

3. GRAPHITE REMAINS STABLE UNDER IRRADIATION AT HIGH TEMPERATURE.

4. USE OF CO^2 AS COOLANT COMPLETELY ELIMINATES THE POSSIBILITY OF EXPLOSION IN THE REACTOR WHICH IS ALWAYS PRESENT IN WATER COOLED PLANTS.

5. URANIUM CARBIDE AND GRAPHITE ARE ABLE TO RESIST HIGH TEMPERATURES.

DISADVANTAGES OF GAS COOLED REACTOR

1. FUEL LOADING IS COSTLY.

2. DUE TO HIGH CRITICAL MASS LARGE AMOUNT OF FUEL LOADING IS INITIALLY REQUIRED.

3. IF HELIUM IS USED INSTEAD OF Co^2 THEN LEAKAGE MAY OCCUR.

4. CONTROLLLING THESE REACTORS IS A COMPLICATED TASK.