TEPCO resumes cooling of Fukushima fuel pool
The operator of the damaged Fukushima Daiichi nuclear plant has resumed cooling of a fuel storage pool at the facility. The work had been suspended due to failure of a water cooling pump.
The pump at the Number 4 reactor building pool stopped working on Monday night after becoming burnt. The pool holds 1,535 spent and unused fuel rods, the most at the plant.
Tokyo Electric Power Company, or TEPCO, used a backup pump, but on Tuesday, it also broke. The firm fixed the pump on Wednesday, and restarted it at around 6 PM.
TEPCO says the pool's temperature at 11 AM on Wednesday was 40 degrees Celsius, up six degrees from a day before. As of 5 PM, the temperature had risen to 42 degrees.
TEPCO expects the temperature to fall by about 10 degrees over next 12 to 24 hours.
The firm plans to begin removing the rods from the pool by the end of next year.
But experts say they're worried about the pool's anti-earthquake resistance despite ongoing reinforcement, as the pool was severely damaged by a hydrogen explosion following the March 2011 disaster.
The operator of the damaged Fukushima Daiichi nuclear plant has resumed cooling of a fuel storage pool at the facility. The work had been suspended due to failure of a water cooling pump.
The pump at the Number 4 reactor building pool stopped working on Monday night after becoming burnt. The pool holds 1,535 spent and unused fuel rods, the most at the plant.
Tokyo Electric Power Company, or TEPCO, used a backup pump, but on Tuesday, it also broke. The firm fixed the pump on Wednesday, and restarted it at around 6 PM.
TEPCO says the pool's temperature at 11 AM on Wednesday was 40 degrees Celsius, up six degrees from a day before. As of 5 PM, the temperature had risen to 42 degrees.
TEPCO expects the temperature to fall by about 10 degrees over next 12 to 24 hours.
The firm plans to begin removing the rods from the pool by the end of next year.
But experts say they're worried about the pool's anti-earthquake resistance despite ongoing reinforcement, as the pool was severely damaged by a hydrogen explosion following the March 2011 disaster.
The pump at the Number 4 reactor building pool stopped working on Monday night after becoming burnt. The pool holds 1,535 spent and unused fuel rods, the most at the plant.
Tokyo Electric Power Company, or TEPCO, used a backup pump, but on Tuesday, it also broke. The firm fixed the pump on Wednesday, and restarted it at around 6 PM.
TEPCO says the pool's temperature at 11 AM on Wednesday was 40 degrees Celsius, up six degrees from a day before. As of 5 PM, the temperature had risen to 42 degrees.
TEPCO expects the temperature to fall by about 10 degrees over next 12 to 24 hours.
The firm plans to begin removing the rods from the pool by the end of next year.
But experts say they're worried about the pool's anti-earthquake resistance despite ongoing reinforcement, as the pool was severely damaged by a hydrogen explosion following the March 2011 disaster.
Reactor4 takes 3 more days to fix-Backup was stopped too
Posted by Mochizuki on June 6th, 2012 · 1 Comment
Following up this article..Burnt motor of coolant system for reactor4
Tepco found a problem of insulation with the back up pump, they stopped it in the morning of 6/5/2012 as well.
Tepco states they will fix it within 6/6 2012, but Nuclear and Industrial Safety Agency commets it will take 3 days to fix.
Ms. Tanioka, a Democratic Party member of the House of Councilors tweeted like these below,
<Translate>
Talked to NISA about the coolant system of reactor4. Here is the report..on 6/4 the pump to connect the first cooling circulation and the second cooling circulation alarmed to stop, they found burnt mark on the termina of motor and cable. To fix this circulation (A), they turned on the back up circulation (B).
<End>
<Translate>
(Tanioka removed only this tweet. This tweet is the most important.)
They checked the back up circulation (B) just in case, then they found the weakness of insulation between the motor and cable as well. They could see the metal part through the insulation part. For the risk of short circuit, they stopped (B) to fix as well. They estimate 3 days to fix.
<End>
<Translate>
The coolant system of reactor4 is stopped at this moment. The temperature of water is 35℃. They assume it increases by 0.3℃ hourly. It will be about 57℃ in 3 days. The safety regulation is 65℃. NISA explains, it’s simple work, it won’t take longer than 3 days.
<End>
<Translate>
NISA explained the reason of these troubles is because the coolant system is improvised preparation. They plan to replace them with better preparation. For the question that reactor 1 ~3 have the same risk. they did not deny the possibility. This is something to concern. I will keep my eyes on it.
<End>
At 11:00 6/6/2012, the temperature of SFP4 is already 40℃.
and....
Following up this article..Reactor4 takes 3 more days to fix-Backup was stopped too
Tepco restarted coolant system of SFP4 at 18:16 6/6/2012, announced in their daily press conference of 6/6/2012.
The temperature of SFP4 was 42℃.
http://enenews.com/m6-3-quake-hits-off-chiba-m4-2-near-fukushima-daiichi-an-hour-later
05:42 JST 06 Jun 2012 05:37 JST 06 Jun 2012 Fukushima-ken Oki M4.2 2
04:36 JST 06 Jun 2012 04:31 JST 06 Jun 2012 Chiba-ken Toho-oki M6.3 3
01:03 JST 06 Jun 2012 00:58 JST 06 Jun 2012 Miyagi-ken Oki M3.8 1
19:46 JST 05 Jun 2012 19:41 JST 05 Jun 2012 Chiba-ken Toho-oki M3.9 2
19:37 JST 05 Jun 2012 19:32 JST 05 Jun 2012 Chiba-ken Toho-oki M4.4 2
19:14 JST 05 Jun 2012 19:09 JST 05 Jun 2012 Chiba-ken Toho-oki M3.6 1
17:56 JST 05 Jun 2012 17:51 JST 05 Jun 2012 Miyagi-ken Oki M4.1 2
and...
http://enenews.com/nuclear-expert-the-truth-is-the-damage-caused-by-fukushima-is-too-great-for-the-government-of-japan
Japan Nuclear Development and the Disaster of the Fukushima NPP
Fukushima Symposium at University of Chicago
May 5, 2012
Fukushima Symposium at University of Chicago
May 5, 2012
Hiroaki KOIDE: Research Reactor Institute, Kyoto University, Japan
Slideshow, Page 45:The truth of the damage caused by the Fukushima NPP accident[...]The damage is too great for Tepco to compensate.It is also too great for the government of Japan
Full Presentation:
http://fukushima-diary.com/2012/06/burnt-motor-of-coolant-system-for-reactor4/
Burnt motor of coolant system for reactor4
Posted by Mochizuki on June 5th, 2012 · 6 Comments
Following up this article..Coolant system stopped at reactor 4 again, back-up turned on
Tepco published the pictures of burnt motor on their daily press conference of 6/5/2012.
Tepco states the temperature of SFP4 is 34℃.
and.....
http://enenews.com/fluctuating-thermometers-reactor-2-broken-gauges-be-working-appear-be-changing-same-times
Follow-up to: NHK: More than half of thermometers in Reactor 2 not working -- Tepco will start 'start measuring temperatures again by late July' -- High humidity inside reactor blamed
Fukushima Daiichi NPS Unit 2 PCV Temperatures
Tepco
June 4, 2012
http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120604_03-e.pdf
Tepco
June 4, 2012
http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120604_03-e.pdf
Note: Some columns blacked out to highlight relevant data
Return Air Temperature of 114A and 114D:
- CONSISTENT: 5/27 @ 23:00 – 5/28 @ 11:00
- UP: 5/28 @ 17:00 – 5/28 @ 23:00
- DOWN: 5/29 @ 11:00
- CONSISTENT: 5/29 @ 17:00 – 6/2 @ 23:00
- UP: 6/3 @ 5:00 – 6/4 @ 5:00
Supply Air Temperature of 114F and 114H:- CONSISTENT: 5/27 @ 23:00 – 5/28 @ 11:00
- DOWN: 5/28 @ 17:00 – 5/28 @ 23:00
- UP: 5/29 @ 11:00
- CONSISTENT: 5/29 @ 17:00 – 6/2 @ 23:00
- DOWN: 6/3 @ 5:00 – 6/4 @ 5:00
The two yellow columns on the left are the temperatures of the ‘return’ air. The two on the right are the ‘supply’ air.As the red arrows indicate, not only do both ‘return’ temperatures rise, fall and remain constant at the same times, but so do both ‘supply’ temperatures.Additionally, both the ‘return’ and ‘supply’ temperatures fluctuate at the same times.
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