Primary coolant chemistry in VVER units Original Research Article

Operation experience with VVER coolant chemistry has been reviewed. The paper describes the results of measurements of radiation fields in primary system components and occupational doses that are compared with radiation control philosophy based on boron-potassium-ammonia coordinated water chemistry, modified and hydrazine water chemistry. The difference in water chemistry guidelines between VVERs and different current operational practices at VVER utilities are outlined. Special emphasis is given to the ammonia-hydrazine water chemistry on some VVER plants, high temperature filtration and silver behaviour.