Testing of a new high-performance water decontamination system has started at the Fukushima Daiichi plant. When in full operation, the new system should increase water treatment capacity while significantly reducing the volume of waste generated.
|The new high-performance ALPS facility (Image: Tepco)
Testing of the system began on 18 October, Tokyo Electric Power Company (Tepco) announced. It is a newer version of the two ALPS multi-nuclide removal systems that have been in operation at the Fukushima Daiichi plant since October 2012.
Initially the new ALPS system will be run for six hours per day but, after the first week or so, it will be operated around the clock. The new system can process up to 500 tonnes of water per day.
When fully operational the new system is expected to increase total water treatment capacity at Fukushima Daiichi to 2000 tonnes per day. Tepco said it expects the system to help it meet water treatment commitments it has made, and to dramatically reduce the storage of highly-contaminated water on site. "In particular, it will reduce strontium to non-detectable levels, which will reduce the risk of leakage and protect the safety of workers," it said.
The new facility will augment the existing ALPS systems, which consist of Japanese and international technologies. These systems have so far treated some 158,000 tonnes of water from which caesium had previously been removed using Toshiba's SARRY (simplified active water retrieval and recovery system) or the first-stage absorption system supplied by Kurion.
Tepco said that compared with the earlier ALPS systems, the high-performance system will produce 90% less radioactive waste. Instead of producing the "slurry" waste of the older systems, the new system uses filters, it noted.
In addition to the on-site ALPS systems, there are four further water treatment facilities in place to reduce strontium levels in water, Tepco said. Kurion's strontium removal facility has a capacity of 300 tonnes per day. Strontium removal capabilities have also been added to the two existing caesium removal systems - SARRY and Kurion's system - with capacities of 1200 and 600 tonnes per day respectively. A reverse osmosis facility also has a capacity of 500-900 tonnes per day.
Researched and written
by World Nuclear News