Abstract: Block fuel elements are prepared according to application Ser. No. 218,244 of Jan. 17, 1972, and now abandoned, from isotropic graphite granulates and coated fuel particles solely by pressing and without any mechanical processing. The cooling channels are pressed directly along with the other parts of the fuel elements.

Abstract: There are provided pressed spherical fuel elements for high temperature reactors made of a graphite matrix with separate embedded coated fuel and fertile material particles wherein the fuel elements comprise 3 concentric layers including a graphite nucleus or core (1) which only contains fertile material particles (4), this graphite nucleus (1) is surrounded by a graphite zone (2) which only contains the fuel particles (5) and this is encased in a shell (3) of pure graphite, the same graphite material being present in all three layers.

Abstract: Molded block fuel elements having an isotropic structure useful for gas cooled high temperature power reactors are prepared by first producing an isotropic graphite granulate of high density with a definite porosity from a molding powder and then hot pressing this isotropic granulate together with coated fuel particles at low pressure to isotropic fuel element. The molding powder for making the granulate is made from a mixture of natural graphite and binder resin, synthetic graphite and binder resin or a mixture of both types of graphite powder with binder resin.

Abstract: Molded or pressed block fuel elements of high power for gas cooled high temperatures are produced by molding in steel tools using outer dies or bars and punches arranged to be freely moveable in the axial direction and moving said moveable dies or bars and punches in the molding process.

Abstract: Block fuel elements for high temperature power reactors that can be reprocessed simply are prepared in which the feed and breed zones are connected with the graphite matrix directly and without transition. They are disposed separately from each other in such a manner that the feed zones and the breed zones can be separately removed one after the other from the structural graphite. In the reprocessing operation there are recovered uranium 233 from the breed particles, uranium 235 and fission products from the feed particles.

Abstract: Prismatic graphite molded objects for high temperature fuel elements are prepared by producing the outer geometry and the holes for cooling channels and for receiving fuel and fertile materials in the formation of the carbon object.

Abstract: There is provided a process for the production of fuel compacts consisting of an isotropic, radiation resistant graphite matrix of good heat conductivity having embedded therein coated fuel and/or fertile particles for insertion into high temperature fuel elements by providing the coated fuel and/or fertile particles with an overcoat of molding mixture consisting of graphite powder and a thermoplastic resin binder. The particles after the overcoating are provided with hardener and lubricant only on the surface and subsequently are compressed in a die heated to a constant temperature of about 150.degree.C., hardened and discharged therefrom as finished compacts.