[en] In this report the decommissioning of the KEMA Suspension Test Reactor (KSTR) is described. This reactor was a 1 MWth aqueous homo-geneous nuclear reactor in which a suspension of a mixed oxide UO₂/ ThO₂ in light water was circulated in a closed loop through a sphere-shaped core vessel. The reactor, located on KEMA premises, made 150 MW of heat during its critical periods. Dismantling of this reactor, with its many connected subsystems, meant the mastering of activated components which were also contaminated on inner surfaces caused by small fuel deposits (alpha contaminants) and fission products (beta, gamma contaminants). A description is given of the save removal of the fuel, the remote dismantling of systems and components and the disposal of steel scrap and other materials. Important features are the measures to be taken and provisions needed for safe handling, for the reduction of the radiation dose for the working team and the prevention of spreading of activity over the working area and the environment. It has been demonstrated that safe dismantling and disposal of such systems can be achieved. Experience gained at KEMA for the proper dismantling and for safety measures to be taken for workers and the environment can be made available for similar dismantling projects. A cost break-down is included in the report. (author). 22 refs.; 52 figs.; 12 tabs

[en] During the period April 1 through September 30, 1976, the energy production of the KSTR reactor was rather small due to problems with the inventory determinations and a decrease of the critical temperature at power operation for which no explanation could be found. A study program in cooperation with the IAEA will be carried out on the status and prospects of thermal breeders. Work done on the investigation of KSTR samples is mentioned briefly

[en] For more than 25 years (1952-1977) the Dutch electric power research institute KEMA put effort in the development of the so-called KEMA suspension test reactor (KSTR). Although the project is ended a long time ago it is an interesting aspect of the history of nuclear energy in the Netherlands and therefore briefly highlighted in this article

[en] A summary of the KEMA R and D performed in 1987 is presented. It is aimed to give a general impression rather than a complete in-depth summary. The actual management of the R and D program is reflected in the framework of this annual report: the material is presented in seven programs. Thes are: the generation of electricity with fossil fuels, nuclear energy, environmental research, transmission, distribution and consumption, new generating systems (mainly wind energy) and their economy, and measurements and diagnostics. The relative efforts applied in the various fields are presented graphically and the organisation of KEMA and of the KEMA R and D Division is sketched. (author). 110 refs.; 63 figs.; 4 tabs

[en] Results of the dismantling of the KEMA Suspension Test Reactor (KSTR) are presented. The entire operation was carried out over 13 years, totalling 104 man-years. The cumulative received dose was 114.7 mSv, which is below the limit of 200 mSv set by the Radiation Control Group. In total 60 tons of steel, graphite and secondary waste was transported to COVRA. Costs added up to about 15% of the construction cost. 1 fig., 2 refs

[en] The results of various conventional tests with this 1000kW experimental reactor (KSTR) are shown in diagrams. The comparatively high negative temperature coefficient of the reactivity was found to be a great advantage. Some inexplicable temperature differences and temperature changes in the reactor vessel were found. (J.S.)

[en] During the 1st quarter of 1976, reactor operation has been restarted. Difficulties during reactor operation such as release of radiolytic gas, loss of fuel, blocking of sampling bypass, leakages from N₂ supply system, are reported. Instrumental performance, maintenance and repair actions undertaken are mentioned, as are the safety of KSTR operation and radiological safety

[en] Operation experience, the behaviour at higher power levels and experiments with the KSTR reactor are described. Progress in the development of an adsorbent for fission fragments is reported, as are some technological aspects of the reactor. Safety aspects of the KSTR during operation at 600 KW and reactor behaviour at this power level are reported

[en] The KEMA Research Institute, Arnhem (Netherlands) has recently decided to dismantle the suspension reactor. In this paper, history and basic principles of the KSTR reactor are briefly described. Performance and testing during the years 1974-77 and the present-day dismantling of the reactor are considered. (G.J.P.)

[en] The power of the KSTR reactor has been increased up to 200 kW in the fourth quarter of 1974. A description is given of the behaviour of the reactor at increased power level, safety aspects concerned with this new level, the operation of the reactor, instrumental behavior and mechanical behavior. Irradiation investigation of two types of fuels are reported and results are presented. Progress made on the conceptual design of a 250 MWe suspension reactor is described