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Figure 2. General flow-sheet of Total Partition process for commercial HLLW<br />

HLLW<br />

30% TRPO<br />

Adjustment<br />

TRU Extraction<br />

Concentration<br />

and denitration<br />

0.5 M HNO 3<br />

Scrub<br />

Scrub<br />

NH<br />

Am+RE<br />

Np+Pu Cyanex 301 U<br />

4OH<br />

Remove impurity by Adjust to pH 3.5<br />

Denitration to Cyanex 301 extr.<br />

0.3 M HNO 3<br />

0.1M DCH 18C 6<br />

1M HNO 3 Cyanex 301 to cleaning H 2O<br />

0.5 M HBTMPDTP<br />

Am Extraction<br />

RE raffinate<br />

Sr Extraction Scrub Stripping of Sr<br />

Am Stripping<br />

Recycling of<br />

Sr (HAW)<br />

Recycling Am<br />

Cs Ion exchange<br />

DCH 18 C 6 HBTMPDTP<br />

H 2O<br />

0.1M HNO 3<br />

Ion exchanger<br />

waste (HAW)<br />

Cleaning of TRPO<br />

Solidification by<br />

cementation<br />

Non α LLW/MAW<br />

Shallow land disposal<br />

5.5 M HNO 3 0.1 M HNO 3 0.6 M H 2C 2O 4 0.05 M HNO 3 5% (NH 4) 2CO 3<br />

Stripping of Am<br />

To MAW<br />

Stripping of Np+Pu<br />

Recycling<br />

TRPO<br />

Stripping of U<br />

The auxiliary processes of the TP process are now being studied. They include the denitration and<br />

calcination for Am (RE) stripping solution, Np/Pu separation in H 2 C 2 O 4 -HNO 3 solution, the<br />

conversion process for uranium stripping solution and immobilization process for Cs-loaded KTiFC<br />

ion exchanger. The advanced extraction equipment such as pulsed column and centrifugal contactor<br />

for the TP process are also being studied.<br />

5. The radiation stability of TRPO extractant<br />

The radiation stability of TRPO extractant was studied in recent year. The physical properties of<br />

30% TRPO do not have obvious change between a dose of 1 × 10 4 to 5 × 10 5 Gy [19]. Main gaseous<br />

radiolytic products and acidic radiolytic products of 30% TRPO-kerosene extractant were analysed.<br />

Their radiation yield (G value) was determined [20]. At a dose of 1 × 10 4 to 1 × 10 6 Gy, radiolytic<br />

products do not have obvious effect on the extraction. When the radiation dose was above 2 × 10 6 ,<br />

some retention of heave elements were observed [21]. Research indicates that the polymeric products<br />

with high molecular weight cause the retention. The studies show that the TRPO extractant is much<br />

more stable than TBP.<br />

678

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