摘要:
A matrix material for safe temporary and/or ultimate disposal of radioactive wastes suitable for the embedment of radioactive wastes, contains graphite and at least inorganic binder which can be glass, aluminosilicate, silicate, borate and lead sulfide.
摘要:
A package for storing radioactive waste, which is suitable for safe, ultra-long ultimate disposal having a moisture-impermeable, corrosion-resistant graphite matrix and metal-encased waste products, which are embedded into the matrix. A method for producing such packages is also part of the invention.
摘要:
Disclosed is reflector graphic which is characterized in that the main component of the graphite is nuclear-purity natural graphite in addition to silicon carbide and/or zirconium carbide, the pressed pieces are shaped by a combined cold-hot pressing process, and the thermal treatment of the pressed pieces is limited to temperatures of less than 2000° C.
摘要:
The invention relates to a novel design and production of fuel element pebbles which satisfy the requirements of high temperature pebble bed nuclear reactors of the next generation. The invention uses a shell of the fuel element pebbles that is devoid of fuel and consists of silicon carbide (SiC) and/or zircon carbide (ZrC), in addition to natural graphite and graphitized petroleum coke, said shell having a maximum average nominal thickness of 5 mm and preferably only 3 mm.
摘要:
The invention relates to a novel design and production of fuel element pebbles which satisfy the requirements of high temperature pebble bed nuclear reactors of the next generation. The invention uses a shell of the fuel element pebbles that is devoid of fuel and consists of silicon carbide (SiC) and/or zircon carbide (ZrC), in addition to natural graphite and graphitized petroleum coke, said shell having a maximum average nominal thickness of 5 mm and preferably only 3 mm.
摘要:
In order to have carbon fiber reinforced carbon resistant to oxidation, the proposal is for a process by means of which a bonding layer of amorphous SiNx is applied to the carbon fiber reinforced carbon to which in turn is applied a protective layer which is oxidation resistant at a temperature T, where T>400.degree. C. consisting preferably of Si.sub.3 N.sub.4.
摘要:
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.
摘要:
A method and a device for sintering ceramic shaped articles in a furnace which saves costs and energy but provides high throughput. To this end, the shaped articles are guided vertically through the furnace on the helical rib of a stationary, vertically positioned helix by the inner longitudinal ribs of a rotating, vertically standing tube which concentrically surrounds the helix.
摘要:
Previously the conditioning of radioactive wastes took place through binding the waste in a matrix of glass, silicon carbide, cement, bitumen, synthetic resin or vitreous carbon. These processes have many disadvantages, particularly the matrix has poor heat conductivity, insufficient resistant to extraction or poor heat resistance and radiolysis effects. A remedy is provided through a carbon matrix in which there is employed as the starting material graphite which is molded with a binder at a temperature above 100.degree. C. There have particularly proven good as the binder sulfur in admixture with nickel powder from which nickel sulfide forms.
摘要:
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.