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Oct 21, 2021Liked by Tony Maiorana

Back in the day, "greenwashing" was a term that was used quite liberally to describe products or technologies that didn't live up to their claimed environmental bona fides. You don't tend to see that term much anymore, but it's what immediately comes to mind when I think of compostable plastics. "Compostable", when examined more deeply, ends up meaning "compostable given some probably unrealistic length of time".

On the subject of municipal compost -- we've had curbside compostables (Green Bin) collection for about 13-14 years now. It's never been clear that this project is beneficial from a life-cycle point of view. Apparently, the resulting compost is not very useful -- it's too salty to actually grow plants with, due to all the food waste in the input stream.

I suspect that you're right about "degrade on command". Instead of enzymes, it might be accomplished with high pH or oxidants, and end up as a form of chemical recycling. Even then, one can't help but think that the real solutions have to come from reduction and reuse, or perhaps even (shudder) incineration.

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I think the value of composting food scraps at least, especially when mixed with leaves/twigs/grass clipping is that you can divert these organics from a landfill and do aerobic microbial digestion as opposed to anaerobic, which can lead to methane gas formation. Methane is like 22x stronger with respect to global warming potential compared to carbon dioxide.

There was some serendipity when I was talking to someone who used to work at a landfill and he was telling me that they lined it incorrectly (you typically need a 7-9 layer high performance plastic laminate) so now the landfill has to be relined, but the problem is it is full of trash and its leaking methane everywhere.

All because someone wanted to save a few hundred thousand dollars on lining a landfill.

I think that greenwashing is too simplistic of a word because of how easily it is thrown about, but I do think the value chains of these complex processes need to be in communication or the actual "value" in new technologies is too easily lost, especially when implemented incorrectly.

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Oct 22, 2021Liked by Tony Maiorana

Yes, certainly. Another criticism of the Green Bin program here is that the household compostables often do just end up in landfill after all (not because of lack of household compliance, but because Green Bin collections actually do just get taken to landfill for reasons that are unclear). It throws the life-cycle analysis for a loop, for sure.

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oh yeah, I've seen in Cambridge the green bins occasionally get put into the garbage truck whereas in my neighborhood we have private services that do it for about $15/month. Maybe I'll take a deeper look into a large green bin service like NYC.

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You could look into the one here (Toronto) which has been operating since around 2008 if memory serves. They've also recently announced a pilot to look at generating methane for home heating from household compost.

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