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Steel in particular in new plants in the US, the stuff that isn't recycled in arc furnaces, is being made with a mix of hydrogen and CO (both from natural gas),

Steel in particular in new plants in the US, the stuff that isn't recycled in arc furnaces, is being made with a mix of hydrogen and CO (both from natural gas), and there's no reason the mix can't be almost entirely hydrogen (only a token amount of carbon is needed, and some of that ends up in the steel). Direct reduced iron furnaces can be converted to run almost entirely on hydrogen. Cement DOES emit CO2 during manufacture, but it also absorbs it during cure (which, granted, can take decades). That means you can potentially use it for direct air capture in a sort of indirect way. (i.e. you capture the CO2 emitted during calcination, when the CO2 is very concentrated and easy to capture, then the cement itself captures CO2 directly from the air during cure).

DennisP 5y ago
I've been doing some googling and it appears that the US isn't actually building new steel plants. The only capacity increase I could find was bringing old plants back online. All the old stuff (other than recycling) uses carbon. Do you have a link showing what I missed? US Steel has started to look into hydrogen production, but hasn't built anything yet. [0] Europe has some pilot projects for hydrogen-produced steel but nothing operational. [1] We certainly should make that conversion, and also ensure that we use green hydrogen for it, but that's a big change and there won't be much economic incentive for it before we have a decent carbon price. "Renewable hydrogen-based iron production can become the least-cost supply option at a carbon dioxide (CO2) price of around United States dollars (USD) 67 per tonne," but "the hydrogen energy used would equal 1% of global primary energy supply." [2] Carbon capture during cement production of course also lacks economic incentive until we have a carbon price, but I haven't found a specific price it would need. [0] https://www.reuters.com/business/energy/us-steel-norways-equinor-eye-clean-hydrogen-production-2021-06-29/ https://www.reuters.com/business/energy/us-steel-norways-equ... [1] https://bellona.org/news/industrial-pollution/2021-05-hydrogen-in-steel-production-what-is-happening-in-europe-part-two https://bellona.org/news/industrial-pollution/2021-05-hydrog... [2] https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997 https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997
- Robotbeat 5y ago
  Then your Googles left you astray. The US has been building Direct Reduced Iron furnaces which are used to feed arc furnace “mini-mills” (which the US also has been building). The US has NOT been building new coal-fired blast furnaces, instead doing DRI furnaces (including hot briquetted iron) and mini-mills. Mini mills are flexible and can use DRI, HBI, and recycled steel as input (usually in the US they use recycled steel scrap primarily as input as it’s cheaper). DRI/HBI furnaces use a mixture of hydrogen and CO. So they already use hydrogen, but it comes from natural gas. However, this input mix of hydrogen and CO can be changed to be almost all hydrogen (almost CO can also be made electrolytically from CO2, as NASA just did with the Perseverance rover on Mars).
  - DennisP 5y ago
    Thanks, I looked up DRI on wiki, that's pretty interesting.

DennisP 5y ago

I've been doing some googling and it appears that the US isn't actually building new steel plants. The only capacity increase I could find was bringing old plants back online. All the old stuff (other than recycling) uses carbon. Do you have a link showing what I missed? US Steel has started to look into hydrogen production, but hasn't built anything yet. [0] Europe has some pilot projects for hydrogen-produced steel but nothing operational. [1] We certainly should make that conversion, and also ensure that we use green hydrogen for it, but that's a big change and there won't be much economic incentive for it before we have a decent carbon price. "Renewable hydrogen-based iron production can become the least-cost supply option at a carbon dioxide (CO2) price of around United States dollars (USD) 67 per tonne," but "the hydrogen energy used would equal 1% of global primary energy supply." [2] Carbon capture during cement production of course also lacks economic incentive until we have a carbon price, but I haven't found a specific price it would need. [0] https://www.reuters.com/business/energy/us-steel-norways-equinor-eye-clean-hydrogen-production-2021-06-29/ https://www.reuters.com/business/energy/us-steel-norways-equ... [1] https://bellona.org/news/industrial-pollution/2021-05-hydrogen-in-steel-production-what-is-happening-in-europe-part-two https://bellona.org/news/industrial-pollution/2021-05-hydrog... [2] https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997 https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997

Robotbeat 5y ago
Then your Googles left you astray. The US has been building Direct Reduced Iron furnaces which are used to feed arc furnace “mini-mills” (which the US also has been building). The US has NOT been building new coal-fired blast furnaces, instead doing DRI furnaces (including hot briquetted iron) and mini-mills. Mini mills are flexible and can use DRI, HBI, and recycled steel as input (usually in the US they use recycled steel scrap primarily as input as it’s cheaper). DRI/HBI furnaces use a mixture of hydrogen and CO. So they already use hydrogen, but it comes from natural gas. However, this input mix of hydrogen and CO can be changed to be almost all hydrogen (almost CO can also be made electrolytically from CO2, as NASA just did with the Perseverance rover on Mars).
- DennisP 5y ago
  Thanks, I looked up DRI on wiki, that's pretty interesting.