The latest on the progress (or lack thereof) of TEPCO's tragi-comical effort to freeze highly contaminated water in the trench leading from the Reactor 2 turbine building (see my post on 7/28/2014 for details) is that the pipe they've been using to dump ice and dry ice got clogged with dry ice. TEPCO admits there has been no discernible effect of ice/dry ice on freezing the water.
So what's your Plan C?
From TV Asahi News (8/12/2014; part):
“切り札”投入したら「詰まった」東電・福島第一
Fukushima I NPP: TEPCO plays its "ace", which ends up clogging the pipe
福島第一原発の汚染水対策として、地下の坑道を凍らせて水を止める工事で、凍結の“切り札”として投入されたドライアイスの効果が表れていないことが分かりました。
It has been revealed that dry ice, which is being poured [into the freezing pipe] as the surest bet to freeze the water in the underground trench as part of the measures to deal with contaminated water at Fukushima I Nuclear Power Plant, has had no effect.
国と東電は、高い濃度の汚染水がたまる地下の坑道に金属性の管を設置し、冷却液を流して汚染水ごと凍らせる作業を続けてきました。しかし効果が表れないため、先月30日からは氷の投入を始め、今月11日朝までの間に、合わせて222tの氷を投入しました。東電は11日の会見で、凍結の効果について「分からない」としていて、目に見える成果が出ていないことを認めました。さらに、凍結の“切り札”として7日にドライアイス1tを投入しようとしたところ配管が詰まってしまい、それ以降はドライアイスの投入を見合わせているということです。
The national government and TEPCO have been trying to freeze the highly contaminated water in the underground trench by installing a metal pipe and pouring liquid coolant through the pipe [since April this year]. But as the effort has failed to freeze the water, TEPCO has started to pour ice since July 30. Total 222 tonnes of ice have been poured into the pipe as of the morning of August 11. In the press conference on August 11, TEPCO said the effect [of ice] in freezing the contaminated water was "unknown", admitting that there was no discernible effect. Further, when they tried to pour in 1 tonne of dry ice on August 7 as the "surest bet" to freeze the water, it clogged up the pipe. TEPCO has halted the pouring of dry ice.
The pipe through which workers have been dumping ice and dry ice (from TEPCO's photos and videos library 7/24/2014):
The pipe (in purple color) in the diagram:
I am grateful for the news, because it gave me the first laughter of the day. Laughing is good for one's health, I hear (regardless of the topic, I hope).
The purpose of this effort is not clear.
ReplyDeleteIf the idea is to immobilize the water in the trenches in order to end radioactive leakage into the ocean, grouting the tunnels would be easier.
If the issue is the contaminated water, a mobile version of the ALPS or similar on a barge in the harbor would be more direct. TEPCO could just recirculate the trench water though the filtering system if the concern is that pumping water out would simply produce more inflow int6o the trenches.
As is, freezing a large volume of water with dry ice seems amateurish, as it is difficult to pour thousands of tons of dry ice into a 30cm pipe. A cold loop with chilled ammonia or Freon would be much more practical, although the cooling medium may well get contaminated in the effort.
Tragi-comical, that's the word.
ReplyDeleteLooks like the only thing that is getting frozen are the idiots holding the ice.
ReplyDeleteThis whole effort of bring everything to "cold shutdown" has proven that no such thing is possible....literally!
Just as well, that trench water (probably some saltwater) is so radioactively hot that it can't be dealt with properly. Everything Daiichi comes in contact with becomes either radioactive or radioactively contaminated. At those levels of contamination, a filtering system wouldn't last more than a couple of month before having to be scrapped.
ReplyDeleteThere are no answers so far to contain the Daiichi's melts. It's unstoppable. Feed and bleed even if the feed or bleed is not controllable.
Again,
ReplyDeleteHow "hard" IS the trench water?
[crickets]
where is the dry ice in the Pictures. i just see normal ice (water based, not CO2)
ReplyDeletewhat are they trying to do? a japanese crushed ice?
Laugh like a drain?
ReplyDeleteDaiquiri machine!
ReplyDeleteHow hard is the trench water ?
ReplyDeleteI think the trench fries.
Keep on posting please!
ReplyDeleteThe stopple method is used to insert a plugging into a pipe which is temporarily block sections of live pipelines. This method is used for a number of reasons like the affected section of a pipeline could be tapped, plugged and safety isolated without shutting down.
ReplyDelete