The problems of analytical control of concentration and integral parameters in aqueous media of atomic power station with VVER 440

Two new methods of hydrazine concentration determination in laboratory scale for cooling media of primary circuit (PC) and secondary circuit (SC) were developed. In both methods PADAB was used as a reagent with combination of oxalic acid. The first method used those components in aqueous solution, in the second method are in powder form. The reagent eliminate the dependence of hydrazine determination on temperature and are stable for more than 1 year. It is possible to dosage a powder reagent by means of batcher. The powder reagent is also suitable for the determination of hydrazine in PC due to short time of analysis and for the activity of PC about 106-108 Bq/dm-3 the exposition of personal is less. For continual determination of hydrazine SFA were used and the equipment was developed. The equipment enables to determine of hydrazine concentration in 10 min. intervals and higher. A color reaction of hydrazine with PADAB reagent in diluted oxalic acid is used for hydrazine determination. The kinetics of the reaction is slow. The difference of absorbance of mixture of samples and blank is used as a analytical signal after the absorbance reaches the maximum. The volume of sample in a cuvette was 0.5 mL to reduce exposure. For the determination of μg quantity of ammonia a spectrophotometric method was used. The nitrogen reaches with sodium hypochlorite, sodium nitroprusside and salicylic acid in a media. The result is a colour product. Admixtures do not influence the reaction. Detection limit of the method is 5 μg/l. Manual methods for ammonia and hydrazine determination enable to determine each component in their mixture and separately as well. The distillation is not necessary. Oxidation-reduction potential as an integral parameter for characterisation of PC was not used due to bad reproducibility of experiments. The difference for phthalate standard was greater than 150 mV for the electrode of the same type. 51 figs., 26 tabs., 292 refs