Reactor Water Chemistry
The reasons for control of selected chemistry parameters, and some of the
more common methods of controlling these parameters will be discussed. No
attempt will be made to identify specific values of any of the parameters
discussed because of the number of different reactor facilities involved, but
an overview concerning the bases and common methods used will be included.
For operating values and specifications, users should refer to local facility
publications. In addition, some information on tritium is provided.
STATE the following for reactor water chemistry.
Nine parameters controlled
Reason for controlling each parameter
Method of controlling each parameter
STATE the possible effects of abnormal chemistry on core
Specific chemical parameters vary from facility to facility but generally include the following:
pH, dissolved oxygen, hydrogen, total gas content, conductivity, chlorides, fluorine, boron,
and radioactivity. For the parameters indicated, control is generally achieved by one or more
of three basic processes.
Ion exchange in the primary system demineralizer(s) or by supplemental
Oxygen scavenging by hydrogen or hydrazine addition
Table 1 lists the more common chemistry parameters measured and/or controlled, the reasons
each is measured and/or controlled, and control methods utilized.