"Green" use of flyash - going to be big.

[Shannow]

https://www.indiegogo.com/projects/block-plant-on-baldwin-power-stations-building#/

I know this guy, have a block of his stuff (and my stuff) on my desk.

Concrete blocks with 2% of the energy content (CO2 emmissions), of traditional portland cement and 90%+ by weight ash.

Consider that the cement industry are keen to keep fly ash "in it's place" at 20% of the cement portion of finished concrete...this guy will use orders of magnitude more...they really don't like him.

Original Colosseum concrete was ash based...this is better.

When I talk that ash will cease to be a problem in my lifetime...these are the guys who are going to make it happen.

 

[SonofJoe]

Forty years ago, in my uni days, I spent six months working with a firm that, amongst other things, built the electrostatic percipitators at the huge Drax coal fired power station in the North of England. I was lucky enough to go inside one during a scheduled shutdown. It was truly awesome as these things were HUGE and the noise they made when they were struck to drop the ash was LOUD! It was like being inside a very strange cathedral.
If memory serves, a lot of the Drax fly ash was sold to British Steel because it was so rich in vanadium but some also went to cement manufacturers.

 

[Shannow]

SonofJoe,
one of my penance experiences in the late '90s was looking after (amogst other things) the ESPs at Wallerawang Power Station, including trying to tune the HV controllers for them, with the local high resistivity flyash (installed a sulfur trioxide generator to help with that, have a video of an industrial sulfur flame if interested)....every friday afternoon, would spend 2 hours talking to them, seeing their spark rates, doing V-I curves, checking for back corona, and tickling them a bit so that they would keep smoke emissions down over the weekend.

As to Vanadium, Adoption of 1/2-1/2-1/4 (Cr, Mo Va), rather the the traditional 2-1/4 1, Cr Mo in high temp steam mains helped me become a real engineer solving stuff instead of just changing stuff out.

Drax...6x660MW, with the turbine trains sitting at 45 degrees so the turbine house wasn't too long, nor the crane bridge beam to long if they were aligned parallel...easy peasy with modern motor controllers, but the first gys threading the generator rotors must have had balls of steel.

 

[4WD]

Google up 50/50 pozmix - been used in oil well cementing for decades.
Light, strong, long lasting, tight seal/bond, resist corrosive fluids etc ...

 

[Shannow]

Pyrament has been used for half a century in runway repairs...full blown geopolymer with a set time of less than two hours and 100MPa strength.

This stuff will be amazing when our major cities are spalling slabs of portland concrete off their reinforcing and requiring demolition.

 

[SonofJoe]

Originally Posted By: Shannow
SonofJoe,
one of my penance experiences in the late '90s was looking after (amogst other things) the ESPs at Wallerawang Power Station, including trying to tune the HV controllers for them, with the local high resistivity flyash (installed a sulfur trioxide generator to help with that, have a video of an industrial sulfur flame if interested)....every friday afternoon, would spend 2 hours talking to them, seeing their spark rates, doing V-I curves, checking for back corona, and tickling them a bit so that they would keep smoke emissions down over the weekend.

As to Vanadium, Adoption of 1/2-1/2-1/4 (Cr, Mo Va), rather the the traditional 2-1/4 1, Cr Mo in high temp steam mains helped me become a real engineer solving stuff instead of just changing stuff out.

Drax...6x660MW, with the turbine trains sitting at 45 degrees so the turbine house wasn't too long, nor the crane bridge beam to long if they were aligned parallel...easy peasy with modern motor controllers, but the first gys threading the generator rotors must have had balls of steel.


I just Googled the Wallerawang Power Station and I see it used John Thompson boilers. When I was but a mere boy in the '60's, my Gran's flat overlooked the huge John Thompson works in Ettingshall where the boilers were probably built! My dear old Dad used to work at the Tarmac site right next door to Thompson's. Sadly all three, Thompson's, Tarmac and The Old Man are no longer with us.

Drax was my one and only foray into the world of power generation. My old oil refinery, where I cut my chemical engineering teeth, had an Avon gas turbine but to my eternal shame, I never bothered to ask our electrical engineer to give me the tour. About the only thing I remember about the Avon was they used to periodically dump a load of walnut shells into the intake to clean the turbine blades and the exhaust smell was reputedly wonderful!

Although as a young process engineer, you're supposed to be a jack-of-all-trades, I developed something of a specialisation in furnace operation. I can still shut my eyes and remember opening the 'peep holes' of our 550 million BTU/hour crude furnace, hearing the deafening roar and seeing the blinding white light from all those John Zink oil burners going at full pelt. Happy days...

 

[Shannow]

Nice history...and the Turbines were named as Parsons machines, although a GEC Erith design that Parsons sold as theirs.

The Train (made out of a Cortina) that Santa arrives in for the Kid's Christmas party has the original GEC Nameplate on it, which was removed for the Parsons one.

 

[SonofJoe]

Changing subjects, I posted on the thread below about how the introduction of the API SM, Sequence IIIG test indirectly caused several otherwise viable Group I base oil refineries to close down...

https://bobistheoilguy.com/forums/ubbthreads.php/topics/4180263/Difference_Between_SL,_SM,_SN?#Post4180263

I think you can include PRA Adelaide and BP Kwinana in that list. Such a shame. I used to visit both places back in the late 80's and had some fun times there.

 

[Shannow]

LOL, and then we became totally imported basestocks (bar Wagga re-refinery).

I got burned badly when they switched from GrI to GrII turbine oils without telling us.

 

[SteveSRT8]

Originally Posted By: Shannow
Pyrament has been used for half a century in runway repairs...full blown geopolymer with a set time of less than two hours and 100MPa strength.

This stuff will be amazing when our major cities are spalling slabs of portland concrete off their reinforcing and requiring demolition.


Had a home on the beach with rebar/concrete floor supported by huge iron beams set in footers. In less than 10 years it needed major repairs due to the rebar rusting and blowing out the concrete.

This flyash thing is extremely interesting! Off to google...

 

[ecotourist]

Sounds like a good idea. But there are a couple of concerns. Would have to check for PAHs (which may be present) in the fly ash, and of course Vanadium (which is often present).

Many PAH's are carcinogenic and Vanadium appears to be at least somewhat toxic. I'd expect PAHs would be the bigger concern. It's also possible all the PAHs have been consumed if combustion has been efficient enough.

If there are PAH's present, there may be exposure to workers handling, building with, drilling into, breaking, etc blocks having a high PAH content. And as important, would exposed blocks (basements, industrial buildings, car parks, etc) shed PAHs?

I understand that ancient concrete had a high ash content and (apparently as a result) has survived surprisingly well.

Finally, blocks made of fly ash may reduce building site exposures to silica which would be a good thing.

 

[Nate1979]

Do these products produced with fly ash leach nasties into the environment?

 

[69GTX]

Originally Posted By: Nate1979
Do these products produced with fly ash leach nasties into the environment?


If the products break down the chemicals in the fly ash will leach out. The secret is keeping the fly ash chemically bonded to something else. At the municipal waste combustors I operated the fly ash was particularly aggressive loaded with flourines and chlorines. The fly ash had to be mixed in just the right proportions with lime and bottom ash to keep a safe mixture that could be land-filled. We tested the ash throughout the year to ensure it stayed neutral. The fly ash by itself even mixed with lime would never pass EPA protocals. But this cinder block with mostly flyash in as interesting concept. I just don't know how strong it will be and if it will ever break down again once subjected to consistent moisture.

NuRock should go back and fix the typo in the first sentence of their overview.

 

[ironman_gq]

We pour a lot of concrete that has up to 60% of the cement replaced with flyash. Stuff has some great properties but does require a little experience to work with.

 

[Al]

I am wondering about radon in the stuff

 

[Shannow]

Originally Posted By: Al
I am wondering about radon in the stuff


The contractor who manages the piles around here were wondering the same thing, and set up personnel and in situ radiation monitoring for a period...found nothing beyond background.

It's placed the same as in this study.
http://www.flyash.info/2001/envben2/91sutton.pdf

 

[Shannow]

Originally Posted By: 69GTX
If the products break down the chemicals in the fly ash will leach out. The secret is keeping the fly ash chemically bonded to something else. At the municipal waste combustors I operated the fly ash was particularly aggressive loaded with flourines and chlorines. The fly ash had to be mixed in just the right proportions with lime and bottom ash to keep a safe mixture that could be land-filled. We tested the ash throughout the year to ensure it stayed neutral. The fly ash by itself even mixed with lime would never pass EPA protocals. But this cinder block with mostly flyash in as interesting concept. I just don't know how strong it will be and if it will ever break down again once subjected to consistent moisture.


From Oz rules, bound and unbound are treated differently...and power station ash doesn't have as much in the way of nasties as municipal waste.

Bound includes cementitious type applications, and this technology (really not cement, uses geopolymer type reactivity). These have a particular "general exemption" from the EPA where they can be used without leachate testing as they are usually in a fairly alkaline finished state...and well, bound...includes applications like road base, which have some lime in as a binder.

Ashes from my region have been tested in full blown geopolymer tests, which involve strong caustics, and aging at elevated temperatures (65C), and can go 100+MPa and be virtually a ceramic...not much application outside the lab for that. But using similar techniques, one guy I know made some trial roadbase with ash, broken glass and crushed brick that got to 25MPa after a year in situ...there's a section of road near here that was laid over ash and coarse mine rejects that has held up amazingly well.

Because of it's nature, the bottom ash can be used directly in cable trenches and foundations (and potting mix too).

 

[Ducked]

Boat hulls, ferrocement comeback stylee?