When going from 200 Ah to 100 Ah, a 0.6 V cutoff was seen with two empty baskets in the outer channel (Mk-V-7E).
Planned tests for the Mk-V ACM with simulated EBR-II blanket fuel will be performed at ANL-E with a 10-inch module. Tests include a run with the Mk-V-8 repeating operating conditions used in run Mk-V-7F with full loading of undissolved fuel segments in the anode baskets in the outer channel and empty baskets in the inner channel. Also, the operating conditions used in run Mk-V-8, except using full loading of undissolved fuel segments in the anode baskets in both channels will also be performed (Mk-V-9). Finally, run Mk-V-8 or -9 will be performed with materials compatibility coupons.
Proposed conditions for sustained operation of the ACM with simulated EBR-II blanket fuel include using an anode drive rotation speed of 60 rpm, a voltage cutoff of 0.75 V, a 7 weight % uranium concentration in the salt, an electrodeposition current of 600 to 100 A, and a stripping current of 600 A.
Laboratory test conclusions were as follows. A procedure has been developed for sustained operation of the Mk-V ACM. A throughput rate of 7 kg of uranium product per 24-hour per module was demonstrated. Reversing the direction of rotation of the anode drive can eliminate stalls. A higher throughput rate may be achieved if sustained operation can be demonstrated with fuel loaded in the inner anode baskets.
The following run conditions were used for the second irradiated blanket fuel loading. The first segment/product collector no. 1 yielded (including salt) 12.6 kg. The deposition was 200 A for 200 Ah with a 0.45 V cutoff. Reverse rotation was used for the 2-minute washing cycle. For stripping, 600 A was maintained until 0.28 cutoff voltage was reached (approximately 150 Ah). This was followed by reverse rotation for the 2-minute washing cycle. Under these conditions, no significant anode rotation stalls occurred. For the second segment/product collector no. 2, the yield (including salt) was 7.5 kg. The deposition was 600 A to 200 A for 200 Ah with a 0.45 V cutoff. Reverse rotation was maintained for the 2-minute washing cycle. For stripping, 600 A was maintained until the cutoff voltage (0.28 to 0.45 V) was reached (approximately 150 Ah). Reverse rotation was then used for the 2-minute washing cycle. Under these conditions, one significant anode rotation stall occurred.
Significant accomplishments in the treatment process include processing 84 of the 100 driver assemblies by driver treatment. Repeatability of 16 kg of uranium per month for three months has been completed. Eight assemblies have been treated in one month. In addition, 850 kg of low-enriched uranium (LEU) have been cast, and 570 kg of LEU have been shipped.
Blanket treatment started in August 1998. The Mk-V electrorefiner has run two batches of irradiated blankets. Results from the Mk-V anode-cathode module tests at ANL-E are being used to guide Mk-V operating parameters and improvements. The blanket chopper is operational.
For HIP scale-up, three 8-inch diameter HIP cans have been processed, and plans for processing an 18-inch can are ongoing. The ANSO HIP process was used in these cases. The HIP process