Green Building Forum - Cement recycling Mon, 05 Oct 2026 23:24:06 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305901#Comment_305901 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305901#Comment_305901 Sat, 01 Jun 2024 12:36:14 +0100 Mike1 https://www.cam.ac.uk/stories/cement-recycling

There's some more about the trials at https://cambridgeelectriccement.com/cambridge-electric-cement-industrial-scale-trial-launches-in-uk/]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305904#Comment_305904 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305904#Comment_305904 Sat, 01 Jun 2024 18:25:44 +0100 djh Posted By: Mike1This Cambridge Uni cement recycling invention looks to have great potential -https://www.cam.ac.uk/stories/cement-recycling" rel="nofollow" >https://www.cam.ac.uk/stories/cement-recycling

There's some more about the trials athttps://cambridgeelectriccement.com/cambridge-electric-cement-industrial-scale-trial-launches-in-uk/" rel="nofollow" >https://cambridgeelectriccement.com/cambridge-electric-cement-industrial-scale-trial-launches-in-uk/I'd seen some reports of the process, but was waiting to see more. There seems to be some confusion in both articles between 'cement' and 'concrete', or else the process is a lot less useful than it might be. If it really does use 'used cement' then there isn't nearly so much of that around as there is 'used concrete'.]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305907#Comment_305907 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305907#Comment_305907 Sat, 01 Jun 2024 23:48:04 +0100 Mike1 Posted By: djhIf it really does use 'used cement' then there isn't nearly so much of that around as there is 'used concrete'.Crushed concrete is the input and recycled cement + aggregates are the output.

From the podcast I was listening to, if new cement production was to be outlawed in the future (2050? - should have been listening harder), then by mixing recycled cement with other cementitious materials there may just about be enough for core purposes. That's taking into account that the availability of the cementitious materials such as blast furnace slag will reduce too.]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305976#Comment_305976 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305976#Comment_305976 Fri, 07 Jun 2024 21:24:05 +0100 jms452
The demolition industry can't even manage to use crushed concrete as aggregate for more concrete yet. The idea of collecting old concrete and trucking it around the country to extract the small percentage of used cement seems like pie in the sky.

I believe they could run a successful pilot and maybe even niche business in some European cities where there's demolition construction and steel work all going on.

The main downer for the idea at scale is that geographies that are using most of the cement don't have much demolition concrete. These are economies that we really need solve the cement problem for.]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305981#Comment_305981 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305981#Comment_305981 Sat, 08 Jun 2024 22:05:10 +0100 Mike1 Posted By: jms452The main downer for the idea at scale is that geographies that are using most of the cement don't have much demolition concrete. These are economies that we really need solve the cement problem for.Good point. And maybe the economies that have the cement no longer have the blast furnaces (or is that just the UK).]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305982#Comment_305982 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305982#Comment_305982 Sat, 08 Jun 2024 23:58:28 +0100 Peter_in_Hungary Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305987#Comment_305987 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305987#Comment_305987 Sun, 09 Jun 2024 10:51:55 +0100 djh Posted By: Mike1maybe the economies that have the cement no longer have the blast furnaces (or is that just the UK).Not sure I quite understand but AFAIK Tata want to put in exactly the right type of blast furnace - namely an EAF - for if and when the process reaches production scale.]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305995#Comment_305995 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=305995#Comment_305995 Sun, 09 Jun 2024 20:34:10 +0100 Mike1 Posted By: djh
Posted By: Mike1maybe the economies that have the cement no longer have the blast furnaces (or is that just the UK).
Not sure I quite understand but AFAIK Tata want to put in exactly the right type of blast furnace - namely an EAF - for if and when the process reaches production scale.Sorry, I was being too oblique. It's just that the UK is now a net importer (rather than the major exporter it once was) so we have old concrete from which cement coud be recycled, but are reliant on blast furnaces elsewhere (especially in China) that don't necessarily have the old concrete. For example:

- UK steel production 2023 = 5.6 million tonnes (https://worldsteel.org/data/world-steel-in-figures-2024/)
- UK 'true steel use' 2019 = 16.2 (ditto)
Which leaves a large gap (of course the trade flows are bigger than the gap due to different steel types).

At least the EAF at Port Talbot will have a capacity of 3.2 million tonnes, which is about what is currently produced there (albeit half current capacity), so not necessarily any further decline. Unless the customers have found alternative sources of supply by the time it opens.]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=306001#Comment_306001 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=306001#Comment_306001 Mon, 10 Jun 2024 07:55:17 +0100 fostertom
But why are we talking about blast furnaces in connection with recycled cement?]]> Cement recycling https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=306002#Comment_306002 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18133&Focus=306002#Comment_306002 Mon, 10 Jun 2024 11:26:40 +0100 djh Posted By: fostertomBut why are we talking about blast furnaces in connection with recycled cement?Read the original links about the project we are discussing.]]>