Replacement and Upgrade of PW – WT Water Treatment System

Because of increasing demand for clean water, nuclear power plants are searching for more efficient and cost – effective ways to source and select up-to-date water pretreatment technologies. Good example for that kind of improvement is Water pretreatment system modification for Krško Nuclear power plant. The project was implemented in 2005 as turn-key project by the company IONICS, Italba (Italy) in association with Sipro Engineering, Ltd.


Picture 1: 3D image of piping layout


                  Picture 2: Softener's skid                      




Reverse osmosis (RO) is a membrane process in which the salt ions will be excluded while the pure water (permeate) is forced through the membrane.




Picture 3: Reverse Osmosis Membrane 



Electro deionization (EDI) is final stage in producing of demineralized water. It is combined of electro dialysis (ED) and resins ion exchange. The essential components of EDI system are ion exchange membranes, resins and DC electricity. In ED process due to DC current the cations and anions migrate through the membranes. The ED stack contains two flow channels: one for feed and the other for concentrate removal.




Picture 4: Picture: Electro-deionization 

The advantage of this technology is in minor use of chemicals, less waste water release and energy saving. Mentioned upgrade system is releasing very clean demineralized water by means of mechanical filters, reverse osmoses, electro-deionization and degasifying. It is managed and manipulated with Supervisory Control and Data Acquisition (SCADA) and integrated into plant process information systems.


                                                                                   Project Manager: Božidar Linke, B.Sc.E.E.