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10 months agotrains are actually one of the examples where you can get away with lower energy dense fuels, like methanol, ammonia or even compressed hydrogen. sure the range will go down, but for many connections this will not matter that much because it will still be possible to go 1000km with one tank if needed.
In general waste glass and metals can be recycled easily and effectively and in many cases it is energetically efficient to do so compared to making new glass or metals form natural resources. There are a couple of caveats to this though that might be important:
There is a lot of research into metal recycling going on right now though, so that might change soon. :) Just because the technology exists to recycle something does not mean that somebody is doing it unfortunately. Even if it is economical to recycle something – meaning the recycled material would cost less than the virgin material – it is still possible that it isnt done because the market is too niche. For instance borosilicate glass can be recycled and it would be very energy efficient to do so but the market would be too small for anybody to invest in it. I guess energy is still too cheap.
Plastic liners in general are not typically recycled, if there is no easy method to separate them from the base material. This applies to cans, paper cups, metal bottles, furniture and lots of other things. In most cases they still allow the base material to be recycled though. For instance in ferrous metal recycling (cans) the plastic liners might simple be burned away in the electric arc furnace.