Frozen brine flow reactor to reduce event tree
B High temperature D Restore the coolant flow rate
①Continue to
alarming device
0.75 E Shut down the
operate
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2、Event tree analysis steps （1）Determine the system and its components； （2）Analysis of each subsystem； （3）Prepare the event tree； （4）Quantitative calculation；
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3、Typical cases Frozen brine flow reactor to reduce event tree analysis
The reaction is exothermic, therefore in the jacketed reactor into the frozen brine to remove heat of reaction。If frozen brine flow rate reduce, can make the reactor temperature rise, reaction speed, so that the reaction is out of control。There are installed in the reactor a temperature measurement control system, and with the frozen brine inlet valve connection, according to the temperature control of frozen brine flow rate。
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Safety training--Event Tree Analysis
Tree Li
BIT：Safety science and engineering
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0.1
⑦Reaction is
0.25
out of control
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The system status as a "reaction is out of control" are:③、⑥、⑦， The probability of them are:
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3、Typical cases
Each event failure rate：
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alarm
0.99
D^Did not restore the
reactor
0.9
②Emergency shut down
coolant flow E^Not shut down
A Frozen brine flow
rate
0.25
the reactor
0.1
③Reaction is out of control
•
P3 = P(B) × P(D^) × P(E^)
•
= 0.99 × 0.25 × 0.1
•
= 2.475 P(D^) ×P(E^)
0.75
restore the down the reactor
coolant flow rate
0.9
C^Not found the
reactor
0.25
E^Not shut down the reactor
shut down
⑥Reaction is out of control
overtemperature
1、The concept of event tree
Starting from the initial state of the event, according to the development order of accident, divided into stages, step by step, every step from success events and failure events two possible consequences into consideration, and use the attachment for success, the connection failure, until the final result。
Event Tree Analysis
1、The concept of event tree 2、The concept of event tree 3、Typical cases 4、Conclusion
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rate to decrease
B^High temperature
alarming device did not report
0.01
D Restore the coolant flow rate ④Continue to
C Found the
0.75
operate
overtreemacpteorratureD^Did not E Emergency shut ⑤Emergency