The NUR Reactor is a pool-type reactor with an open water surface and variable core arrangement. Its operation is very safe and reliable. Its power output is 1 MWth, cooled by light water and moderated by graphite. It has plate-type fuel elements (MTR type, approx. 20% enriched uranium) with aluminum cladding.

The design of the reactor core and associated control and safety systems conforms to the following criteria:

• The reactor is cooled by natural convection if confronted with a loss of pumping power
• Access to the reactor core from the top of pool level is possible with the reactor operating at full power, in order to facilitate actual implementation of experiments.
• Mechanisms associated with control and safety rods are located on the top of the reactor tank. This aids in the training of personnel and the actual carrying out of experiments, hence:
• A high water column was placed over the core to act as radiation shielding
• The core is cooled by downwards flow which leads to a decay tank beyond the pool to allow for N-16 decay

Reactivity Balance

The reactivity balance of the reactor is controlled by the reactor control and safety plates.

Design Concept

The design concept is based on the requirements of a reactor of versatile utilization. It has been mainly designed for:

• Neutron radiography for research and industrial purpose
• Radioisotope production for medical and industrial purposes (laboratory scale)
• Basic and applied research in reactor physics and nuclear engineering
• Beam port for neutron scattering experiments and neutron radiography
• Materials testing
• Activation analysis
• Materials irradiation
• Training of scientific and technical personnel

Irradiation boxes are used for radioisotope production. Boxes are either inserted in the core or positioned within the external reflector. Manipulation and distribution of irradiated items is carried out within the hot cell located at the reactor.

Two rabbit systems, one central irradiation facility and one reflector irradiation positions are provided for irradiation experiments.

In order to facilitate research activities, the reactor has been provided with neutron beam channels and a Neutron Radiography Facility.

There is an auxiliary pool for spent-fuel storage.

Reactor safety is complemented with a network of radiation detectors located in contamination-risk areas, plus a fire-detection and manual and automatic fire-extinguishing systems.

Auxiliary services such as water supply, compressed air, electrical energy system, communications system, workshops, physical security system and labs are also available.

Computerized supervision and control system

A Multi-Parameter Distributed Processing Data-acquisition, Display, and On-line Supervision and Control Systems is provided,

• To supervise and monitor the various systems involved in the functioning of the installation in order to assist Control Room personnel to operate the plant
• To provide overall visual plant control while maintaining a detailed record of all actions undertaken
• To provide a short and long term recording for analog and digital data for post trip logs, post transient analysis, and event analysis.