! " #$
S. A Tariq, T. M Ashraf, S.P Gupta, B. Pintu, D. Paul & K.V.S Sastri
ABSTRACT
T h e a p pl i c a t i o n o f i o n i z i n g r a d i a t i o n a n d r a di a t i o n t e c h n o l o g y i n h e a l t h c a r e i n d u s t r y, a g r i c u l t u r e a n d r e s e a r c h i s o n e o f
t h e m o s t s i g n i f i c a n t p e a c e f u l u s e s o f n u c l e a r e n e r g y a l o n g w i t h t h e n u c l e a r p ow e r g e n e r a t i o n. Am o n g t h e s e t h e r a d i a t i o n
p r o c e s s i n g u s i n g g a mm a r a ys i s t h e m o s t p o p u l a r a n d b e n e f ic i a l ne x t t o t h e t e l e t h e ra p y t r e a t m e n t s o f c a nc e r. I o n i zi n g
r a d i a t i o n s u s e d f o r r a d ia t i o n p r o c e s s i n g a r e m a i nly,
- r a ys f r o m r a d i oa c t i v e i s o t o p e s a n d e l e c t r o n be a m s /X - r a ys f r o m
a c c e l e r a t o rs . Am o n g t h e s e t h e - r a ys f r o m C o b a l t - 6 0 r a d i o i s o t o p e i s t h e m o s t w id e l y u s e d c o n s i d e r i n g t h e e n e r g y o f e m i t t e d
p h o t o n s , h a l f - l i f e a n d m e a ns o f p r o d u c t i o n f o r d e v e l o p i n g c o u n t r i e s . T h e B o a r d o f R a d i a t i o n a n d I s o t o p e Te c h n o l o g y ( B R I T ) a
u n i t o f D e p a r t m e n t o f At o m i c E n e r g y ( D AE ) i s t h e o n l y r a d ia t i o n s o u r c e s u p p li e r in I n d i a . B R IT c a r r ie s o u t f a b r i c a t i o n , s u p p l y
a n d p o s t s u p p l y jo b s i n a s ys t e m a t i c a n d s a f e m a n n e r. B R I T s u p p l yi n g s e a le d s o u r c e s a s p e r t h e d e ma n d i n t h e c o u n t r y a n d
a b r o a d w i t h t h e C o - 6 0 p r o d u c e d i n v a r i o u s I n d i a n P H W R p o w e r r e a c t o r s a s a b yp r o d u c t o f n e u t r o n r e g u l a t i o n .
INTRODUCTION
Radiation
p r o c e s s i n g us i n g
- r a ys
from
r a di oa c t i v e
i s o t o p e s a n d e l e c t r o n b e a m s / X - r a ys f r o m a c c e l e ra t o r s h a s
g o t w i de ra n g e o f a p p li c a t i o n s . T h e r a d ia t i o n p r oc e s s i n g
u s i n g g a m m a r a ys i s t h e mo s t p o p u l a r a n d b e n e f i c i a l n e x t t o
t h e t e l e t h e r a p y t r e a t m e n t s o f c a n c e r. Ga m m a ra y s f r o m
C o b a l t - 6 0 r a d i oi s o t o p e i s t h e m o s t w i d e l y u s e d c o n s id e r i n g
the energy of emitted photons, half-life and means of
p r o d u c t i o n f o r d e v e l o p i n g c o u n t r i e s . E a rl y r e a l i z a t i o n o f
i m p o r t a n c e o f r a d i oi s o t o p e s a n d r a di a t i o n t e c h n o l o g y f o r
societal
b e ne f i t s
and
national
d e v e l o p me n t
by
the
D e p a r t m e n t o f At o m i c E ne rg y ( D AE ) r e s u l t e d i n d e v e lo p m e n t
a n d s e t t i n g u p o f i n f r a s t r u c t u r a l f a c i li t i e s i n t h e c o u n t r y f o r
harnessing the benefits of nuclear technology for the benefit
o f s o c i e t y. T h e P r e s s u r i ze d H e a v y Wa t e r R e a c t o r s ( P H W R )
p r o g r a m m e f o r p ow e r p r od u c t i o n c r e a t e d a n o p p o r t u n i t y t o
t a k e u p p r o d u c t i o n o f c o ba l t - 6 0 o n l a r ge s c a l e . R AP P C O F a
s e c t i o n o f B R I T e n g a g e d in c u t t i n g a n d r e c o v e r y o f C o b a l t 6 0 a c t i v i t y f r o m a d ju s t e r ro d s , f a b r ic a t i o n , s u p p l y a n d p o s t s u p p l y jo b s o f s e a l e d s o u r c e s w i t h a n n u a l p r od u c t i o n
c a p a c i t y o f 2 - 3 M i l l i o n C u r i e s o f C o - 6 0 a c t i v i t y.
MATERIALS AND METHODS
N a t u r a l c o b a l t ( C o - 5 9 ) c a n b e u s e d i n r e g u la t i ng a n d
a d ju s t e r r o d s f o r n e u t r on r e g u l a t i o n i n N u c l e a r P ow e r
Reactors to serves the purpose of providing reactivity
c h a n g e s a n d a ls o p r o d u c e s a u s e f u l i s o t o p e o f c o b a lt c a ll e d
C o - 6 0 . T h i s w a y, a l l t h e n e u t r o n s o t h e rw i s e w a s t e d u s e d f o r
p r o d u c t i o n o f C o - 6 0 a n d u s e d f o r t h e b e n e f i t o f s o c i e t y.
27C o
59
+
0n
1
→
27C o
60
+7.8MeV
( T 1 / 2 ) : 5 . 2 7 ye a r s
C o b a l t i s p r o d u c e d i n tw o f o r m s s l u g s / p e l l e t s a s p e r t h e
s p e c i f ic a c t i v i t y ( C i / g ) r e q u i r e m e n t o f s e a l e d s o u r c e s . B o t h
t h e s e f o r m s o f c o b a l t a r e e n c a p s u la t e d i n z ir c a l l o y c a p s u l e s
a n d a g a i n s e a l e d i n a z i rc a l l o y p e n c i l a n d 6 / 8 s u c h p e n c i ls
f o r m a s u b - a s s e m b l y ( S A) w h e n a s s e m b le d t o g e t h e r. F o u r S A
are mounted on a support tube of zircalloy attached to
retention
support
( l a t c h)
at
one
end
is
c a ll e d
an
a d ju s t e r / a b s o r b e r r o d . S pe c i f i c Ac t i v i t y i n c u r i e s pe r g r a m
s p e c i f i e s t h e l e v e l o f a c t i v a t i o n i n a r e a c t o r.
T h e p r o c e s s i n g o f C o - 6 0 i n c l u d e s re m o v a l o f a d ju s t e r
f r o m r e a c t o r, t r a n s p o r t a t i on t o R AP P C O F, d i s c h a r g i n g a n d
s t o r a g e o f a d ju s t e r r o d s i n s t o r a g e p o o l , U n d e r w a t e r
c u t t i n g o f t h e a d ju s t e r, s e p a r a t i o n o f s u b a s s e m b l ie s , t h e
separated sub assembly cutting for recovering the raw
activity in Hot Cell. The Hot Cell is a specially designed
s h i e l d i n g e n c l o s u r e h a v i n g w a ll t h i c k n e s s o f a b o u t 2 m o f
c o n c r e t e a n d r a d i a t i o n s h i e l d i n g gl a s s w i n d ow s o f
e q u i v a l e n t t h i c k n e s s , e qu i p p e d w i t h re m o t e h a nd l i n g
M a s t e r S l a v e M a n i p u l a t o rs ( M S M ) a n d i n - c e l l c r a n e . T h e
r e c o v e r e d a c t i v i t y i s u s e d f o r v a r i o us s e a l e d s o ur c e s
f a b r i c a t i o n a f t e r i n s pe c ti o n o f p r i m a r y c a p s u l e f o r
c o n t a m i n a t i o n a n d l e a k . T h e s e c o n d a r y e n c a p s u l a t io n i s
d o n e i n S S p e n c i l s o f s t a n d a r d s i z e u s i n g G a s Tu ng s t e n
Ar c W e l d i n g ( GTAW ) . T he a c t i v i t y m e a s u r e d s e a l e d s ou r c e
is transported to the end user in a type approved
t r a n s p o r t a t i o n f l a s k s a s Typ e B ( U ) p a c k a g e a f t e r f i n a l
contamination and leak test.
RESULT & DISCUSSION
The Co-60 sealed sources are used in a number of
a p p l i c a t i o ns i n a g r i c ul t u r a l i n d u s t r y a s w e ll me di c a l.
R a d i a t i o n t r e a t m e n t o f s e w a g e s l u d g e , s t e ri l i za t i on o f
health
care
products,
ir r a d ia t i o n
of
various
agricultural/food products for different purposes such as
r a d i a t i o n pr e s e r v a t i o n o f f r u i t s a n d v e g e t a b l e s , s p r o u t
i n h i b i t i o n i n o n i o n a n d p ot a t o e s , v u l c a ni z a t i o n o f r ub b e r
latex, decontamination of spices etc are some of them.
Te le t h e r a p y t r e a t m e n t o f c a n c e r, bl o o d i r ra d i a t i o n e t c a re
some of the medical application of Cobalt-60 sources.
CONCLUSION
T h e s u c c e s s f u l a p p l ic a t i o n o f r a d i a t i o n t e c h n o l o g y i n t h e
i n d u s t r y a n d h e a l t h c a r e p r o d u c t s i s t h e r e s ul t o f t h e
c o n t r i b u t i o n o f a l a r ge n u mb e r s c i e n t is t s a n d e n g i ne e rs o f
B h a b h a A t o m i c R e s e a rc h C e n t r e ( B AR C ) , B o a r d o f
R a d i a t i o n & Is o t o p e Te c h no l o g y ( B R I T ) a n d N u c l e a r Po w e r
C o r p o r a t i o n o f I n d i a ( N P C IL ) , w h o h a v e w o rk e d t i re l e s s l y
to master the technology of processing of large quantities
o f r a d i a t i o n s e a l e d s o u r c e s . D e ma n d o f C o - 6 0 i n c re a s e d
n o t a b l y d u r i n g l a s t 1 0 ye a r s d u e t o t h e p ri v a t e
entrepreneurs
entered in the
f i e l d o f r a d ia t i o n
p r o c e s s i n g . At t h e f a c i l i t y w e a re c o m mi t t e d t o t i m e l y
supply of sealed sources to the end users in a safe
m a n n e r & s t r i c t l y i n c om p l i a n c e w i t h At o m i c En e r g y
R e g u l a t o r y B o a r d ( AE R B ) r e g u l a t i o n s a n d w il l c o n t i nu e t o
c o n t r i b u t e t o t h e s o c i e t y.
ACKNOWLEDGEMENT
T h e w o rk p r e s e n t e d i s t h e r e s u l t o f c o n t r i b u t i o n s m a d e
b y d e d i c a t e d t e a m o f e n g i n e e r s a n d s c i e n t is t s o f B R I T
u n d e r a b le g u i d a nc e o f Dr A. K . K o h l i , C h i e f Ex e c ut i v e B R I T.