Siemens Aktiengesellschaft

Kraftwerk Union Aktiengesellschaft

Kernforschungsanlage Julich Gesellschaft MIT Beschrankter Haftung

Dietmar Bege

Siegfried Meininger

Anwer Puthawala

Karl-Heinz Kleinschroth

Horst Queiser

Dietmar Erbse

Karl Friesner

Heinz Mallek

Horst-Otto Bertholdt

Gerhard Kratz

Klaus Blinn

Klaus Kuhnke

Robert Grigat

Eckhard Fischer

Lydia Fuchs

Wolfgang Schlenter

Egon Zange

Karl Trumper

Wolfgang Schmitt

Helmut Stu/ Nkel

Hans-Joachim Faust

Gunter Wittrowsky

A method and a device are provided for disposing of an aqueous solution that contains an organic acid and an iron complex and occurs particularly in the decontamination of radioactively contaminated surfaces of components. It is contemplated that the iron complex in the solution is reduced by irradiation with UV light. A dissolved iron salt and carbon dioxide, which is given off, are formed in the process. An oxidant is then added to the solution that contains the dissolved iron salt and the organic acid. This produces water, and the iron complex forms once again. Some of the dissolved iron salt is removed from the solution by means of a cation exchanger. The solution containing the iron complex is irradiated again with UV light. A cycle process ensues, which continues until all the organic acid is consumed.

Method for disposing of a solution containing an organic acid

A method of reducing the volume of a mixture of filter fibers and a powder-form ion-exchange resin, produces a waste product that is particularly suitable for ultimate disposal. A solvent which dissolves the filter fibers is added to the mixture and a mixture which is thus formed is first dried and then given an additional heat treatment.

Method of reducing the volume of a mixture of resin powder and inert

A process for treating radioactive waste in the form of contaminated powdery ionic exchange resin to make it suitable for final storage by reducing its volume as much as possible, includes mechanically dewatering the ion exchange resin. The dewatered ion exchange resin is mixed with a calcium compound. The mixture is dried at temperatures of up to 120.degree. C. and preferably about 50.degree. C. to 60.degree. C., and at a pressure of from 120 to 200 hPa, until a residual moisture content of less than 10% of the mass of the mixture is reached. The dry mixture is thermally treated at a pressure below atmospheric pressure by heating up to a temperature of from at least 120.degree. C. to at most 190.degree. C. The ion exchange resin thereby loses its water absorption and swelling capability. Ion exchange resins treated in this manner are processed with cement or bitumen to form blocks that are suitable for final storage.

Process for treating radioactive waste

A method and apparatus for drying sewage sludge includes diverting steam escaping during the drying of the sewage sludge and feeding the steam to a compressor. Thermal energy of the compressed and therefore heated steam is supplied to the sewage sludge to be dried through a heat exchanger system. Condensate is drawn off from the heat exchanger system and collected. Thermal energy of the condensate is supplied to the sewage sludge prior to the drying for reinforcing a preliminary degassing.

Method and apparatus for drying sewage sludge

Reducing the volume of radioactively loaded liquids, particularly evaporator concentrates, by heating in a storage container up to solidification, wherein liquids are replenished for filling up the storage container. Heating takes place discontinuously in heating periods separated from each other in time. The heat is introduced directly into the container contents. Vapors produced are drawn off intermittently.

Method for reducing the volume of radioactively loaded liquids, and

A method for the determination of the setting process in an inorganic aqueous binder system, in that the electrical conductivity is constantly measured in the binder system, in that the variation of the electrical conductivity is differentiated according to time, in that the variation of the first derivative of the conductivity is monitored, and in that the temperature in the binder system is continously measured and the temperature dependence of the electrical conductivity is eliminated by means of the measured temperature values.

Method and apparatus for the determination of the setting process in an

For bonding particularly radioactive wastes into a binder, a transporting and mixing device is used which transports the mixture to a storage tank prior to the hardening. The wastes are transported into the mixing zone by gravity and aided by the conveyor helix which also imparts additional wall cleaning action through the dry conveyor zone. A single or multi-component binder is concurrently transported in a direction lateral to the mixing tool to the mixing zone. The mixture is conducted in a straight-line extension of the transport and mixing direction to an outlet to which the storage tank is connected.

Device for bonding wastes in a binder

A process for the conditioning of contaminated waste through cementing. Dry waste is cemented, especially waste which is recovered as ashes subsequent to the combustion of burnable waste, or as a dry residue during the treatment of sludge. In the process there is added to the dry waste a cement component not less than about 50% by weight of the weight of the waste, wherein subsequent to the admixing of the waste with the cement, there is mixed in water to the cement in a slightly excess stoichiometric ratio of effecting the setting, and the mixture is compacted under pressure and then encased.

Process for conditioning contaminated waste through cementing

Apparatus for the conditioning of radioactive wastes capable of ultimate storage, using a multicomponent binding agent, with a continuous-flow mixer, a filling station for the ultimate storage barrels, a receiver tank for liquid waste materials, a silo for a component of the binding agent, and several conveyors. A premixer for the one binding agent component and for flowable waste materials is provided. The premixer is connected via throughput measuring devices to the silo and to a container for flowable wastes. The premixer is connected via a dosing conveyor device to one end of the continuous-flow mixer. Thereafter, the receiver tank is connected to the continuous-flow mixer. A discharge conveyor device which feeds the ultimate storage barrels is mounted at the other end of the continuous-flow mixer.

Apparatus and method for conditioning radioactive wastes for ultimate

Method and apparatus for conditioning weakly to medium-active wastes through fused vitrification by means of electric electrodes for generating the melting heat. The wastes optionally with additive materials are filled into a cup-shaped melting crucible which contains at least two electrodes. The melting crucible is closed off at the top by a furnace hood which has current leads. Voltage is applied to the electrodes via the current leads until the melting crucible containing material to be melted has melted. The current leads are separated from the electrodes. The furnace hood is removed, and after the cooling down, the melting crucible is filled with inactive cement paste to produce a cover layer.

Method for conditioning weakly to medium-active wastes

Treating weak-to medium-active ion exchanger resins which are dried in a drying container by means of heat and in a vacuum, before they are transported into a storage container, the heat being introduced by heat conduction via the drying container into the ion exchanger resins. The heat is conducted via metallic heat transfer surfaces into the bulk of the resins leaving a core of at most 100 mm thickness. Steam from the moisture in the resin is conducted at the same time into a condenser via a discharge line, with an underpressure of 300 mbar or less.

Treating weak-to medium-active ion exchanger resins in a drying vessel

Solidifying radioactive liquid concentrate residues containing borates by embedding in a binder by mixing. Prior to embedding, sodium hydroxide is added to the waste concentrate to obtain a mole ratio of sodium to boron of 0.25 with a corresponding pH value in the range of 7.3 to 8.0 or 0.7 with a corresponding pH value of 9.8 to 10.2. The waste concentrate with added sodium hydroxide is mixed with a binder to embed it into the binder.

Method for solidifying boron-containing radioactive residues

Method for the ultimate disposition of radioactive wastes by vitrification, in which weak to medium radioactive waste concentrates from borate-containing radioactive liquids are mixed with added glass-forming materials, maximally in a ratio of 1:3, and the mixture heated to obtain a glass-forming melt.

Method for ultimate disposition of borate containing radioactive wastes

Mixing devices such as worm machines used for embedding radioactive wastes in hot bitumen are cleaned to remove residual bitumen and salt incrustations in three successive operations: (a) Washing with a solvent for bitumen in a volume amount equal to about the free space of the device. (b) Rinsing with a water-soluble rinsing medium miscible with the solvent in a volume amount the same as (a). (c) Rinsing with demineralized water in a volume amount twice (b). Pumice gravel is used to absorb the solvent and rinsing medium and the resultant pumice embedded in bitumen and sent to ultimate storage.

Growing community of inventors

Erlangen, Germany

Dietmar Bege