Or English v French naming of products, had that quite a few times at a Bricolage.
Hi Corona… I meant to respond earlier, but have been on a tiring exam panel and then writing the feedback since yesterday am. As I understand it after fact checking the 1200 deg C quoted as normal for Lime and Natural Cement is about right.
In more detail:
Historic England states pre-industrial lime kilns were “ burning calcium carbonate at temperatures above 900°C.”
Wikipedia (lime kilns page) states “due to temperature peak at the burners up to 1200 °C in a shaft kiln conditions are ideal to produce medium and hard burned lime.” Other sources describe how the lime is passed via a pre-heat zone to a burning and sintering zone, then to a cooling zone “after preheating, it begins to decompose at 850°C, and completes calcination at 1200°C”. The temperature at peak is shown as about 1800 deg C in the mid zone in an HPS Lime Kiln, but 1200 Deg C in a PFR lime kiln. It appears that approx 130 deg C higher flame heat is needed to ensure the lime is sufficiently calcinated.
Lime production also emits “1.2 tonnes of CO2”per tonne of lime, only compensated for by the later process of reabsorbing carbon over a long period.
Whereas Portland Cement kiln temperatures are described on the Wikipedia cement kiln page as in the “sintering zone of rotary kilns range at around 1450 °C. To reach these, flame temperatures of about 2000 °C are necessary”. An Imperial College report states that re cement currently “every tonne emits up to 622 kg of carbon dioxide”.
So using either cement or lime causes a massive amount of carbon, and its really desirable to mix it with fillers such as hemp that absorb and store carbon. I saw something recently that suggested a large portion of the carbon footprint of construction comes from excavation, so extracting the raw materials is also a significant problem.
(https://historicengland.org.uk/images-books/publications/iha-preindustrial-lime-kilns/heag222-pre-industrial-lime-kilns/
https://www.researchgate.net/publication/319916223_Lime_Shaft_Kilns
https://www.sciencedirect.com/science/article/pii/S1364032122006505
(Best ways to cut carbon emissions from the cement industry explored | Imperial News | Imperial College London)
I’ve bought Hammerite paint to repaint the outside walls of a very old metal shed.
It appears to have been excellently spray painted in the factory about 40 years ago. The paint has held up well in sunshine in all weathers. It’s just a bit powdery on the surface, very very rare dots in one or two places where it looks like the original metal was galvanised.
Having painted Hammerite metal paint straight onto a naked galvanised zinc mailbox last year, only to find it’s peeling this year…I have stocked up on Hammerite’s special primer for galvanised metals to redo the mailbox, and then do the shed.
However Hammerite’s instructions say before applying the primer wash with a diluted ammonia 3%? solution, in water with a dash of washing up liquid. Do they mean white spirit? I also have a bottle of acetone around if this is what they mean instead.
I gather this primer sticks to anything. So can’t see any harm in putting it over the old paint that will doubtless still be left on the shed close to intact after I wash off the top dusty layer. And it will cover the very rare, tiny few spots of galvanised metal showing through. It’s a beauty update and I really, really don’t want it to peel.
I’ll test on the mailbox first but can anyone tell me by diluted ammonia into initial wash of galvanised metal before the special primer do they mean white spirit?
Surely ammonia and white spirit are quite different things?
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PS it took a while but I did manage to crack how to avoid the ridiculous prices in France for Hammerite. Will post if anyone likes Hammerite as much as I do and wants to know.
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It’s “Salmiakgeist” in their German leaflet (where the primer is manufactured) and their English leaflet had it as “spirit of ammonia”
Sometimes translators don’t know what we commonly call things… It’s whatever would degrease a galvanised surface, presumably some chemical loosening of the relativeky low oxidation deposits you get on galvanised metal over time.
The same primer works with other nonferrous metals like copper. So I think especially for my job the degreasing element is the more important.
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White spirit is very different from ammonia as Vero says. ‘Spirit of ammonia’ seems to be used in smelling salts to prevent fainting, so I wonder if there’s been a bit of a hiccup in translation. Google translate gives Liquid Ammonia for Salmiakgeist, and that sounds more reasonable.
FWIW Ammonia is actually a gas, dissolved in water. I’d guess that the purpose here is to remove grease, react with any rust and slightly etch the surface to provide a key.
I used to think it was the bee’s knees but it’s not been the same since they got rd of the VOC’s
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Yeah I agree. But Hammerite is still the best metal paint around for us DIY’ers I think.
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That’s exactly what Salmiakgeist, is white spirit is petrol based not ammonia.
Also be careful and read the composition of the paint as Hammerite paints have diversified over the years. And not all paints will adhere to old Hammerite.
So what is liquid ammonia sold under the name of? the leaflet mentioned a 3% solution then making up 10% of the bucket - with a splash of dishwashing liquid also
In Oz/NZ there used to be a household name product called Janola you’d toss a splash of into a washing machine or use neat as a bleach - it was ammonia but I’ve never seen it this side of the world
Look in most bricos supermarket etc stock it, ammoniaque alkali.
I’d just wash down with lessive St Marc.
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Thank you Wozza
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Yes, wary of Hammerite composition changes - recently even from year to year - this is from the instruction leaflet in the box of their special primer that’s just been delivered.
I really miss the old b*mbproof metal coating of original Hammerite with VOC’s… Sniff! sniff! 
Luckily this Hammerite will be going over Hammerite’s special primer over the original factory painted surface (de-dusted and degreased)… i’ll overcoat only with Hammerite eventually though I know that’s not always a picnic. Though I’m hoping not for another 6-8 years…
Not in my book it isnt since they ruined it as Billy says. Rustoleum combi colour beats it hands down these days. Ammonia is sold in most brico sheds in 1 litre bottles and some supermsrkets.
Ta Corona. Always willing to develop another option. The colours look nice and I can see they have some Hammertone choices so I might try it out on some garden furniture next year.
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I used a lot of yellow for gas supply pipes, others faded to a magnolia shade from yellow, combi colour still yellow after 8 years outdoors, put myself out of work doing that. Others went back and repainted with their cheap paints and got paid two or three times unlike me.
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Hi JoCo, I am surprised by this and doubt the data was comparable as it takes a lot more energy to raise a furnace temperature from 900c-1200c ( I was trained that lime was around 950 compared to portland cement) to the circa 1800c and therefore more CO2 in that process?
With only a month to go before I build some non structural walls and having no response from the lime block company, will I go with std parpang blocks availble everywhere and quick to work with or buy chanvre (bagged) and add lime as a binder to shuttered forms to lightly tamp the lime chanvre into the shuttering. Then finish the walls with lime render.
What do you think?
Thinking about the planet is fine but taking your second option will only please you and any future owner of the walls won’t give a fig.
Assuming the walls are at your french property then if you facture in the co2 created by travelling there and back perhaps option 2 might mitigate the co2 usage but how long will it take to achieve option 2 against option 1?
Given that modern France is built with concrete blocks at least their solar, hydro and wind power does go some way to balance the books.
Its not just the CO2, the chanvre/lime construction also keeps the environmental conditions better, no mold, no damp, no condensation and self reguating humidity, all without adfitional mechanical climate controls
And a great thermal insulation.