Re: the power of junk, Is Parallel Programming Hard, And, If So, What Can You Do About It?

On Sat, 24 May 2025 20:36:50 -0000 (UTC)
John Levine <johnl@taugh.com> wrote:

According to BGB  <cr88192@gmail.com>:

Don't forget to factor in energy costs.  The energy costs
to refine and produce virgin aluminum are very high, relative
to the costs of recycling aluminum. 

>
Granted, but possibly depends on the relative cost of energy.
>
But, likely, as more total aluminum is produced the relative cost of
aluminum would go gown. While recycling aluminum makes sense, it
does come with the tradeoff that recycling aluminum reduces the
relative cost of aluminum (and thus the value of producing new
aluminum would go down), so is less likely to be favored by the
primary producers (where a relative scarcity is better for profit
margins, ...). 

 
Aluminum is produced from bauxite which is around 40% aluminum and
needs a multi-step energy intensive process to turn into metallic
aluminum.  But aluminum scrap is already metallic aluminum.  My
impression is that we are about as far down the experience curve as
we are likely to get, and using scrap as a source will always be far
cheaper than bauxite.
 

Aluminum from bauxite is almost pure aluminum. Aluminum from scrap
contains significant and unpredictable amounts of magnesium, copper and
silicon. Removing them is hard, in case of copper very hard.

Your profit margin thing is backwards -- producers charge whatever
the market will bear for the product (plus tariffs these days which
is a separate issue) so the more scrap they can use, the lower their
costs so the more money they make.