R1.01/04 A - Liquid radioactive waste treatment system (LRWTS) for Kola NPP - Lot 4 - Valves of connection between process system

Kola NPP consists of four VVER-440 power units and comprises two special buildings where liquid radioactive waste (LRW) storage vessels are located. These two special buildings were constructed during the 1st construction stage (Units 1 and 2) and 2nd construction stage (Units 3 and 4) respectively. Accumulated LRW is temporarily stored in stainless steel tanks. It has to be processed in such a way as to allow for safe long-term storage, transportation and final disposal of such waste.

It has been decided to renovate the Liquid Radioactive Waste Treatment Unit (LRWTU) at Kola NPP in order to create a complex of process systems, installations and equipment for handling and treatment of waste which has been accumulated up to the present time and in future. This will be done by means of solidification to reduce the initial amount of waste and conditioning for controlled safe storage and further final disposal.

The complete LRWTU includes the following sub-systems, units and equipment (see the block diagram of the complete LRWTU in the attached diagram):

• А1 – dissolution and extraction of salts (R1.01/94G);
• А2 – concentrating (R1.01/96C);
• А3 – cementation of waste ion-exchange resins and sludge (R1.01/04A Lot 3);
• А4 – extraction of liquid radioactive waste from storage tanks (R1.01/94G);
• А5 – removal of radionuclides from evaporator concentrate solutions (R1.01/04A Lot 5/1 and R1.01/04A Lot 5/2);
• Transport/process equipment for handling the solidified waste (R1.01/04A Lot 1);
• Radiation control (monitoring) equipment (R1.01/04A Lot 2);
• Auxiliary systems and units;
• Solidified waste storage facility.

Several of the above systems and components of the LRWTU have been provided through the TACIS programme, as indicated in the above list (see projects R1.01/94G, R1.01/96C, R1.01/04A Lots1-5). Project R1.01/04A Lot 4 comprised the supply of valves for installation at the connections between the different process systems. A feasibility study was also performed in the framework of project R1.6/91.

Project R1.01/04A, programmed in the TACIS Annual Action Programme of 2004, was the so-called 'large-scale' equipment supply project for Kola NPP. It was divided into several lots in order to purchase the remaining equipment needed for the construction of the LRWTU.

The present contract was for Lot 4. Under this contract, a set of valves for installation at the connections between the different process systems of the LRWTU was delivered.

The set of valves of connection between process systems of LRWTU includes:

• isolation valves;
• check valves;
• control valves.

Scope of supply

The scope of the Supply comprises one set of valves, consisting of:

• 67 stainless steel, electrically driven isolation valves for pipelines of various sizes ranging from 25 to 80 mm diameter;
• 14 stainless steel check valves for pipelines of 32 and 50 mm diameter;
• 2 carbon steel, electrically driven control valves for pipelines of 50 and 80 mm diameter.

The scope of supply includes the design, manufacture, supply and supervision for installation and commissioning of the valves. It also includes the provision of documentation, acceptance testing, certification, assistance to the End User in licensing and the required training of KNPP personnel.

The specified equipment was delivered, installed and commissioned and all services, including training of End User personnel, were satisfactorily performed. The Provisional Acceptance Certificate (PAC) was signed in December 2009. The warranty period was completed in accordance with the contract and the Final Acceptance Certificate (FAC) was signed in December 2010.