Project Background
The original radioactive waste management strategy at NPPs with VVER reactors had been based on the accumulation of all kinds of waste during entire operational period and its storage for later processing during the first stage of the decommissioning. Due to exhaustion of a free space in storage facilities for the "as generated" waste, however, the Ukrainian NPP waste management strategy was later revised and the NPPs started designing and constructing plants for collection, processing and storage of radioactive waste.
Under such circumstances, a special interest was focused on the waste treatment technologies as, for example, volume reduction, reusing and recycling of the waste materials, etc. to better utilize the available waste storage capacities.
In the aim to support this trend and recognizing the significance of this problem, the EC decided to initiate a project aimed at back fitting of the existing radioactive waste water treatment facility at the Khmelnitsky NPP. Following this, the U1.04/93A project was established.
Project Objectives
The overall objective of this project was to contribute to a safe and sound management of the radioactive waste in Ukraine, in particular at the Khmelnitsky NPP.
The specific objective of this project was to provide a proven system for the treatment of the backlog of radioactive waste water at the Khmelnitsky NPP, in particular to arrange for implementation of a centrifugal technology for the purification of waste water from suspensions (sludge) and colloids. The scope of expected project work included design, manufacturing, certification, acceptance tests and delivery of the Liquid Radwaste Treatment System equipment and associated services.

Project Results
This project was initiated in 1996; however the tender procedure (1998) was not successful. The tender dossier, reflecting the additional requirements of the Beneficiary, was republished in 2002 and the project finally started in 2004. The project Contractor was the Ansaldo Energia SpA, Italy.
The preparatory phase of the project implementation included an extensive feasibility study using specific experience with such systems in EU countries as well as in Russia and Ukraine. There were considered also results of the similar TACIS projects (e.g. that for the Rovno NPP).
The Liquid Radioactive Waste Treatment System (LRWTS) was then designed to treat drainage water, sludge water and spent filtering materials coming from existing KhNPP tanks.
Based on the design, the necessary equipment of the LRWTS was delivered and installed at the KhNPP, including:

• Components of the centrifugation system (waste tank, decanter, separator, sampling station, dryer);
• Associated valves and piping;
• I&C system and a system for the automatic control of centrifugation process;
• Electrical equipment;
• Radiation protection system and equipment;
• System for packaging and handling of solid radioactive waste, produced in the liquid waste treatment process;

The LRWTS has been located in four rooms (C-153, C-155, C-236 and C-338) of the KhNPP Auxiliary Building. The main components have been as follows (see the attached Figure 1):

1. C-338� - Waste Tank for collection of liquid waste to be further processed. Its stirrer prevents sedimentation of solids in the lower part of tank to be separated in the decanter.
2. C-236 - Decanter, the first-stage centrifuge, produces the waste fluid for filling drums, while sending not completely purified water to the second stage - a separator.
3. C-236 - Separator, the second-stage centrifuge, which purifies ‘clean’ water from the decanter to be reused back in the plant; the outflow of the waste ‘dirty’ water is re-circulated back for further treatment.
4. C-155 - The sampling station, where quality of waste may be checked after drum filling before drying.
5. C-155 - The dryer, where drums are heated up to about 102 �C and negative pressure is created by a vacuum pump to remove humidity from the waste.

After the equipment installation, the KhNPP personnel were trained in four courses:
Siemens courses for programmers of Siemens’s SIMATIC control system were held in four 2-week sessions from June to October 2009. A course on centrifugal system was held from 5 to 9 November 2009 including 3 days of theoretical training on the system component and 2 days of practical field training on the system operation. A course on drum handling system was held from 25 to 29 January 2010 including three days of learning about individual system components followed by one day of in-field demonstrations and one day of mastering maintenance activities. The last course, which was dedicated to automated control system, was held in three weekly sessions from 7 December 2009 to 5 March 2010, including (1) general architecture of the system, (2) system sensors and (3) system control logic.
Training was in average provided to 25 people including operators and maintenance personnel. In all sessions, also trainers for future courses were involved. In total, more than 150 man/weeks of equivalent training were provided.
After completing of the personnel training, on-site tests of the Centrifuge System with radioactive media were performed. Ansaldo participated in the tests as an observer. Three tests were successfully performed from 6 to 9 April 2010. Small technical problems with a pipeline clogging were resolved by KhNPP personnel immediately. The expected characteristics of the drum content were achieved. Cleaning factor was 99.93%. The residual humidity of the waste was reduced from 45% to 2-5% (final value depended on the drying time), meeting the criteria for transportation of the drums in a storage facility. After the tests, the system was put in trial operation.
Following the installation of the LRWTS, an update of the Final safety Analysis Report was issued in cooperation of the Ansaldo with the Kiev Energoprojekt (KIEP).
Conclusion
The project has fully met the objectives stated in the relevant section of the ToR.
The main benefit of this project has been separation and reuse of water separated from the radioactive sludge. The radioactive effluent can be now transformed into a solid form suitable for compact storage and further handling. The operation of the system in general contributes to reducing volume of the "as generated" waste, prevents waste accumulation and enhances the radioactive waste management at the Khmelnitsky NPP to a level corresponding to international recommendations and requirements.