DE7733503U1 - DISPOSAL CASE FOR RADIOACTIVE WASTE - Google Patents

Description

The invention relates to a repository for radioactive waste for direct mixing of radioactive waste in lumpy, liquid or paste form with known binders such as concrete or bitumen.

Cementing, embedding in bitumen or thermoplastics and polymerisation in casting resins are used to transfer radioactive waste into containers suitable for final disposal. For this purpose, the waste material must be thoroughly mixed with the binding agent. When cementing, this is generally achieved by stirring with a stirring device in a mixing vessel or in the final storage vessel itself (eg DT-PS 1 771 2kk) . It is also known to absorb waste materials in mixtures of cement and porous filler material (DT-AS 1 109 279). When bituminizing an extruder screw is often used as a mixing device (DT-AS 1 589 839), for pre-dried material the sedimentation in the hot bitumen results in a satisfactory embedding (DT-OS 23 Ok 96l). Cast resin mixtures are preferably pressed into the waste material placed in the final storage container or sucked in with a vacuum (DT-OS 2 511 957).

These methods and devices have the disadvantage that when \ ^r Before Using external mixing systems Kontaminationsproblerae occur or the mixing process or the mixing means to be relatively expensive.

It was therefore the object of the present invention to provide a repository for radioactive waste to be found in which a direct homogeneous premixing of radioactive waste with known binders can be carried out, so that no radioactive contamination of external mixing systems and mixing devices

can take place. Waste disposal should also be included these vessels can be done easily, without special expenditure of time and as cheaply as possible.

This object was achieved according to the invention in that the Final storage vessel contains an insert that is stuck during the mixing process and is suitable for the mixing process. Preferably used you can use metallic scrap parts from any Manufacturing processes that are brought into the repository container as individual parts or assembled are advantageous so that they only attach to the inner wall of the vessel during the mixing process set and thus form a solid mixed insert. Of course, several inserts can also be placed in the vessel be introduced.

The inventive installation of lost inserts that Repository vessel transformed into a mixing device. The advantage of this device is that the inserts consist of, for example cheap metal manufacturing waste welded together or -can be riveted and that any series barrel approved for storage can be used as the final storage container ■ can be. The use of activated or contaminated metal parts or scrap is particularly advantageous nuclear systems as mixed operations. In addition, the cementing results in the well-known advantages for the end product Reinforced concrete construction: increased strength and permanent corrosion protection.

It is particularly advantageous to use the repository vessels during the mixing process with a replaceable and reusable cuff to be provided in order to be able to use the entire volume of the vessels for the waste mass. The mixing process itself takes place first

preferably by setting the vessels in a tumbling motion, "for example by means of a turntable or a Gymwheel mixer.

Figures I to III show schematically exemplary embodiments the repository according to the invention and the Mixing devices.

Figure I shows a 200 1-roll beaded barrel (l) with an insert (2), which is made from lumpy workshop waste (pipe pieces, Vinkeleisen, Sheet metal remnants, wearing parts, etc.) by punctiform Welding is made in such a way that it is stuck in the barrel by jamming and catching. The barrel stands on a rotatable Plate (3) and is tilted about an axis (4) in

jj inclined position. Relocate the drive and support rollers (5) It turns into a slow rotating movement: cement is fed from a silo to the barrel via a dosing screw and from a batching vessel radioactive waste sludge through a rotary valve. This is, for example, evaporator concentrate from a boiling water reactor with approx. 20-30 / 0 dry matter content (Essentially chlorides, sulfates, and phosphates as well

ί oxalates and citrates of sodium, potassium, calcium and iron).

140 liters of evaporator concentrate and 220 kg of SuI fadur cement are used in 20 minutes put in the constantly moving barrel. In order to fully utilize the final storage volume in spite of the inclined position, A sleeve (6) with fixed mixer fittings (7) is placed on the barrel, which prevents the cement paste from overflowing.

After the mixing process, the barrel is placed vertically and takes up the entire amount of waste. The cuff (6) will removed and attached to the next barrel. The barrel will then

closed with a lid. After 12 hours, the contents have set to such an extent that they can be loaded onto the final storage site without any problems can be transported.

The figure II shows a 400 1-barrel (12) that with lost Inserts (13) provided as in Figure I and with 175 kg (= ■ 280 l) centrifuged, radioactively loaded ion exchange resins in spherical form j 65 1 water, 2.5 1 concrete liquefier and 210 kg of Portland cement is charged. The barrel is tightly closed with a lid (14) and placed in a drum wheel mixer (12) staggered for half an hour. A homogeneous, pulpy mass is formed by the lost mixing components. To Removal of the barrel from the mixer sets the cement within a few hours. The container can be transported after approx. 24 hours,

Figure III shows a 200 l barrel (l6) with lost concrete shielding (17), into which the fragments (18) of a used, contaminated fuel element cutters are placed. By wedging the fragments (18) are fixed in place with a circular perforated plate (19) in the barrel (16). After placing the with internals (20) provided sleeve (21) the barrel is set in rotating motion. A sludge pump delivers within 15 Minutes 135 1 of a filter sludge with around 25% by weight of dry substance, essentially kieselguhr with the pre-precipitated cleavage and activation products Co, Cs and Sr (as hydroxides, carbonates Phosphates and Hexacyanoferrate), into the barrel. At the same time 200 kg of a 1: 1 mixture of Portland and Trass cement metered in. When the addition is complete, mixing is continued for approx. 10 minutes, then the barrel is placed vertically and after pulling off the cuff (21) with a lid attachment device locked. The final storage condition is established by casting with a concrete plug.

Frankfurt / Main, October 24, 1977
Dr.Br.-Bi

Claims (6)

7215 KN NUKEM GmbH 6450 Hanau 11 Final storage container for radioactive waste. CLAIMS 1. Disposal barrel for radioactive waste for direct mixing of this waste with binding agents, characterized in that the container (1) contains an insert (2) that is stuck during the mixing process and is suitable for the mixing process. 2. Final storage vessel according to claim 1, characterized in that the insert (2) consists of metallic waste or scrap parts. 3. Final storage vessel according to claims 1 and 2, characterized in that the interest rate (2) consists of contaminated or active waste parts. 4. Final storage vessel according to claims 1 to 3, characterized in that the Gofäss (l) contains several inserts. 1111 ItII 5. Endlagerg-efäss according to claims 1 to 4, characterized in that the inserts are not attached to the inner wall of the vessel. 6. Repository vessel according to claims 1 to 5, characterized in that the vessel (l) carries a sleeve (6) during the mixing process. ^ > T