Tritium instrumentation for the Chalk River Nuclear Laboratories tritium extraction plant

Tritium technology in fi~ion, fusion and isotopic app~cations 3.

577

TRITIUM INSTRUMENTATION FOR THE CHALK RIVER NUCLEAR LABORATORIES TRITIUM EXTRACTION PLANT, E. C. Davey, R. G. C. McElroy and S. Kupca (Chalk River Nuclear Laboratories)

A tritium Extraction Plant

(TEP)

is under construction at the Chalk River

Nuclear Laboratories (CRNL) for the extraction of tritium from the heavy water moderator and coolant of research and power reactors owned by Atomic Energy of Canada Limited. be 40 g.

The annual production of tritium from the TEP is planned to

Tritium is extracted from heavy water feed by means of a liquid

phase catalytic exchange and a cryogenic distillation process. tritium gas is stored

as a metal hydride

process equipment will contain a large inventory of tritium operating

personnel

must

be

continually

The product

in sealed containers.

aware

of

process

Since the

(~20 g), plant stream

activity

levels for economic reasons and promptly alerted in the event of leakage for personnel

health

Consequently, continuous

protection

purposes

and

measurement

of

tritium

contained

building air and the plant exhaust stacks. taken

to

inventory

loss

minimization.

the TEP is equipped with a number of tritium monitors for the

provide

tritium

monitoring

at

in the process

equipment,

the

This paper outlines the approach the

TEP

for

health

protection,

environmental and process requirements and describes the general features of specific monitors in each classification.

4.

DEVELOPMENT OF AN INTEGRATED MONITORING SYSTEM FOR A NEW TRITIUM FACILITY AT MOUND, T. B. Rhinehammer, T. E. Burgess and E. L. Spyrou (MEC-Mound)

A

stand-alone

system

for

the

monitoring

of

process

support

services

and

tritium levels in gloveboxes, room air, room exhaust ducts and stack exhaust was developed at Mound.

Sixty tritium monitors were built and interfaced to a

Health

room,

Physics

control

where

all

tritium

levels

abnormal conditions appear as alarms on wall displays.

are

displayed

and

The control room was

designed for full remote control of all monitors with the exception of those for gloveboxes,

and for control and alarm display of many other functions,

including the purge rate for glovebox atmosphere and the selection of room air discharge to stack or to a tritium cleanup system.

The monitoring system was

also interfaced to a data gathering computer and an automatic dialing alarm system.

5.

A MODULATED FLOW TRITIUM MONITOR, R. G. C. McElroy, R. A. Surette and M. J. Wood (Chalk River Nuclear Laboratories)

A

tritium-in-air

concentration

to

monitor allow

which phase

utilizes

modulation

sensitive

detection

of is

the

input

tritium

described.

This

measurement technique is useful in those measurement situations where there are slowly varying interferences from other radiations or species; or wher e it is

necessary

to

measure

to

quite

low

concentrations.

Immunity

to

interferences is increased, because, in general, the frequency spectrum of the interferences are peaked to zero frequency and will not have major components at the modulation

frequency.

The

sensitivity of

the monitor

is increased

because it is not limited by input leakage currents nor slow drifts in zero.