On water regime in direct cycle power reactors

The paper discusses ideas about standardizing the reactor water regime of single-circuit nuclear power plants, namely, with respect to the content of the chlorine ion, silicic acid, iron oxides and degree of hardness. It has been shown that the consumption of reactor for decontamination should be calculated on the basis of the chlorine ion under conditions of 100% condensate decontamination, the permissible chlorine ion concentration in the reactor water being taken at the level of 200 μg/kg. Increasing this consumption with a view to improving the removal of iron oxides from reactor water results in lower efficiency without significant effect on iron oxide removal. Prevention of iron oxide deposits in the reactor in a fixed water regime requires standardization of iron oxides in the reactor water at the level of their solubility with correspondingly more rigorous standardization of iron oxides in the feed water. The water-regime and heat-engineering designs of the loop from the condenser to the reactor in a single-circuit power plant should be based on considerations of maximum heat economy and strict standardization of iron oxides in the feed water. (author)