Callide Power Station 6

[hacksaw]

What is the likely cause?

CS Energy, which runs Callide Power Station Queensland AU), said there was a fire in one of the plant's turbines.

"That tripped the other three units, that then was a serious reduction to generating capacity in Queensland," CS Energy chairman Jim Soorley said.

The station was evacuated and a 550-metre exclusion zone put in place as fire crews worked to extinguish the blaze.

 

[davefitz]

Large steam turbines often schedule "fast valving" of the IP turbine intercept valves, alternately closing one then the other at part load , to ensure that corrosion products do not cause these fast acting valves to stick open. If the unit had a steam to reheat bypass system, it is possible that such an excercise had led to a stuck intercept valve, which could have oversped the turbine. Don't forget that 80% of the steam turbines power is generated across the IP+LP stages.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

 

[RRaghunath]

I suppose the company ha obligation to release preliminary investigation report in three days or so. Can some one clarify on that please!!

 

[byrdj]

I was hoping the Fire Fighters might leak some photos.

 

[hokie66]

Don't worry about failure of one power station, this is the danger.

https://www.spectator.com.au/2021/05/lathams-law-77/

 

[itsmoked]

Indeed! That's a bad deal. Same thing the USA is letting happen in rail cars and e-buses.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[dik]

Funny... Australia and the US have nearly twice the per capita carbon footprint that China has... might be something else...

https://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions_per_capita

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[hokie66]

What is your point, dik? Do you want to live under the Chinese system? And while you were at it, why not include Canada in your list?

 

[dik]

Nope... but a person has to be careful about pointing fingers... three of the fingers on the hand are pointing back at the pointer...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[hokie66]

I'll use my whole hand to point, then. But still want to know what your meant by "something else", and indeed how carbon footprint relates to China's attacks on the Western economies.

 

[byrdj]

Unit B1 will be returned to service on 11 June...
B2 on 21 June...
Unit C3 will return to service on 22 June...
return date for C4 of 12 months’ time.

I would expect damages to the other, in service, turbine/generators during the "Black" coast down. one possiblity would be inadaquate cooling bearing oil, either while spinning down or sitting while hot. (sure there is balance of plant equipment that might also have suffered)

 

[itsmoked]

They're stating the re-start dates. Do we even know why the unit blew?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MDEAus]

Finally a picture, it's behind a paywall though and it's ant size.

the attachement is the best I could do.

 

[MDEAus]

This is a screen clipping from the below video, bottom right is the HP IP turbine then in the centre is the LP and then on the left is the generator.

https://youtu.be/qEWAFgxRXa0?t=26.

Turbine hall was evacuted before the incident, by reports due to the "turbine not sounding right" and "overheating" according to un-sourced claims in the AFR.com artlice below

https://www.afr.com/companies/energy/inside-the-callide-c-power-station-disaster-20210602-p57xai

 

[MDEAus]

This one should be bigger.

 

[itsmoked]

That shaft and coupling broke and were tossed out into the concrete sinking a foot into it. Seems more like maybe it went radically out of balance causing the shaft to fail.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[FacEngrPE]

A radically out of balance condition could include loss of baldes. The HP turbine location looks a bit battered.

There are some bright spots in the roof that are not light fixtures, possibly holes resulting from flying parts.

 

[LittleInch]

TBF that looks like a concrete cover over some sort of void, but a big bang for sure.

It's not going to be generating any electricity for quite a while, if ever.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[byrdj]

...before the incident, by reports due to the "turbine not sounding right" and "overheating" ...

I wonder what the generator MW output before incident. (also what they were doing)

I can think of two conditions that could cause "funny sound and overheating".

If there was a lost of condensor cooling allowing back pressure to increase will overheat the long last stage buckets. an increase in temp will cause them to be thrown off. the gen end of the LP hood looks missing, but I would expect hood to have more damage.

discription of plant state the steam cycle was "advance". IF it incorperated HP/IP by passing steam for quick start to hot unit, there should be "cooling" steam going through HP/IP as LP is used to roll the genenrator, failure of that valving arangment would over heat te HP/IP and cause rotating and stationary to try and "lock-up"

the damage to HP/Ip seems concealed by the extremely damaged lagging.
I can't tell if the piece of the coupling embeded in concrete is A or B (between IP and LP or LP and generator)

assuming the initation was a mechanical failure of turbine, the fire would have started when the bearing cavities were torn apart. the following loss of oil pressure would defeat the generator shaft seals allow 60 psig H2 to be blown in to the oil fire

looking at the torn off end of the couple reminds me of a remotely possiblity would be grid torsional vibration causing the shaft to crack and eventially shear.

 

[MDEAus]

Not a concrete floor but a steel grid mesh floor, not enough spalling for concrete floor, during overhauls they cover with ply wood. Highly energetic failure for sure though, LP and generator didn't suffer like the IP HP side.

I bet the person who ordered everyone out of the turbine hall is glad they made that decision. Usually work this incidents it's questioning why people weren't evacuated.

Given that the generators casing is largely intact that would seem to rule out hydrogen explosion? If it was an issue with hydrogen leaking into the LP turbine through severe vibration it would detonate the LP turbine.

300kg debris craned from the turbine hall roof. Wonder how far debris spread. There are a few new sky lights.

 

[MDEAus]

Gen output according to NEMlog was approx 280MW, they had ramped down from 400MW as per an early post. Power state had been pretty steady at 280MW then it had an unplanned disassembly.