Download Continuous Sterilization

Advantages of Continuous
Sterilization process over Batch
Sterilization
 Better protection of medium value .
 Batch sterilization wastes energy and can overcook the
medium
Batch sterilization uses steam or direct heat to elevate the
temperature. Both the heat and the cooling water are spent
with no opportunity for energy recovery.
 temperature in batch sterilization can not increased
beyond 121°c as if the temperature is increased, the heating
& cooling period increases .
 hence during sterilization the nutrient media will be
degraded .
 Continuous Sterilization is the method of choice .
 In Continuous Sterilization , the medium to be sterilized is
dealt in small increments &
 hence there is shorter heating & cooling periods.
 much higher temperature can be utilized , thus reducing
holding time
 therefore, in continuous sterilization nutrient degradation
is subsequently less as compared to batch sterilization .
This is more efficient than batch sterilization because
instead of expending energy to heat, hold, and cool the
entire system, small portions of the inlet streams are heated
at a time
Batch sterilization
Continuous sterilization
Time ( in min)
Holding temp. ( in min)
Shorter sterilization time means
lesser thermal degradation of
medium
Continuous Sterilization:
 Most of the sterilization in the continuous sterilization
process may occurs in the holding
The holding section is a long pipe,
λhold
=
L
uav
length of the pipe
average fluid velocity
in the pipe
 High steam utilization capacity. As compared to batch
sterilization
 The heat can be fully utilized during sterilizing process and
 therefore, great amount of water and steam can be saved as
well as energy consumption is decreased substantially.
 It can averagely save about 30% of steam and 40% of cooling
water throughout the sterilization process if Continuous
Sterilization Technology is applied.
 Easy Scaling-up of the process .
 On scaling up the fermentation it was very difficult to
attain the correct sterilization conditions using the batch
regime .
 Continuous sterilization using direct steam injection
allowed the design of a precise process producing sterile
medium with the required degree of interaction b/w the
ingredients .
The temperature profile of the medium allowing an easy
estimate of the Del factor (∆) required. This makes scaleup very simple.
 Easier to automate the process
The Continuous Sterilizer is not a pressure vessel and is
easy to automate the whole process .
 hence improves the quality of sterilization & reduce labor
intensive
 Reduces manpower, machinery replacement and
maintenance
 Reduction of sterilization cycle time