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The most interesting sentence isn't the headline, but rather:

> Landfills accounted for 41% of the source emissions it identified, manure management 26% and oil and gas operations 26%.

i.e. perhaps the best reason to recycle or compost is to avoid the methane emissions from natural decomposition.

Compost IS natural decomposition, my dude.

True, but it's an aerobic decomposition that produces CO2. Landfills tend to create anaerobic environments, where decomposition produces methane. Both are greenhouse gases, yes, but methane is the more potent of the two.

A composting operation could potentially capture its gasses though, compared to landfills.

There are landfills that capture methane too. Some even turn it into onsite power source (in which case it’s re-emitted as co2 but oh well)

It's still good news, since methane is a more potent greenhouse gas - depending upon the timeframe and calculation method it's generally reckoned to have between 30 and 100 times the warming potential of C02 [1]. Moreover a power station then has a CO2-rich exhaust stream, which is probably the best place for industrial carbon capture.

[1] https://www.scientificamerican.com/article/how-bad-of-a-gree...

Sunnyvale does this! The "Sunnyvale Materials Recovery and Transfer Station" (SMaRT Station) is out by the bay, and there is a waste water treatment plant right next door. Methane is captured from "capped" landfills and is used to power the treatment plant. I believe the plant is nearly 100% powered by these captured gases.

Doesn't smell great over there, but it sure is interesting and pretty smart!

sure, but at least the compost doesn’t go to waste :)

Only in the same sense that farming is "natural" - we're using biological processes that would never happen without our careful construction and maintenance of the circumstances.

> i.e. perhaps the best reason to recycle or compost is to avoid the methane emissions from natural decomposition.

Uhhh, I think you may want to rethink that. Rotting things, whether in a landfill or in your ecologically principled compost heap in your back yard releases methane.

Methane is produced by anaerobic decomposition; composting is defined by the regular aeration (and sometimes watering) of the compost pile, which allows aerobic bacteria to break down the pile more cleanly. You do still get some GHGs, but much less.




Your own references point out that aerobic and anaerobic composting are different processes; the latter, which is most of backyard composting (if your heap ain't hot, it ain't aerobic), produces about as much methane as a landfill does, without the ability to collect and burn off the methane.

It boggles me that people emotionally or tribally react to a fact about how chemistry works, google things which support their emotional reaction, and ... don't read what was in their citation.

The first reference does not refer to anaerobic methods as "composting", but as fermentation:

> Decomposing organic material in anaerobic conditions — by microbes in the absence of oxygen — releases methane into the atmosphere. Anaerobic fermentation is common in landfill and open stockpiles such as manure piles [azernik: Manure piles are the second big contributor to methane emissions listed in OP.]

The second one just refers to "anaerobic decomposition".

In both cases this is something they mention as the alternative to composting, i.e. they literally define composting by its use of aerobic decomposition methods.

And yes, I agree that this is a complicated biochemical process that should be done by professionals in dedicated facilities (EDIT: which is where most composting happens in California), not in people's backyards. Where did you hear me arguing for amateur backyard piles?

most backyard heaps are hot, it's actually not hard to do

That sounds like the sort of thing that could be fixed by educational material.

A little methane from the back yard is still better than landfill. But the math for commercial composting vs amateur might need some scrutiny. Transport to the composting facility should also be part of the arithmetic there.

Is most composting done in the backyard? I never even considered composting until I moved to California where the government handles it for me

Worth noting / just pointing out : one common approach to orchard composting [which influences some backyard operations] is to avoid turning it in an effort to 1) promote fungal development and 2) save labor/money

Yeah methane is released inside a compost pile but some of it is consumed by the compost pile by other reactions. That is literally the point of a compost pile versus just a pile of garbage.

Still waiting on Elon Musk to make "WasteX" which will take vast amounts of garbage from landfills and fly it directly into the Sun.

My friend and I were seriously thinking this was a good idea until we read an article [0] destroying it completely. Lol

0:"Here's Why We Can't Just Throw Our Garbage Into the Sun" https://www.popularmechanics.com/space/a19666/we-cant-just-t...

Another explanation[1] that shows how it's not just the cost of escaping Earth gravity (which is high enough already) but the delta-v required to de-orbit. It's easier to throw the garbage out of the solar system than it is to descend into the Sun.

[1] https://www.youtube.com/watch?v=LHvR1fRTW8g

It would be much less costly to just throw it all at Venus. b^)

Thank you for this link! I always assumed it would be ridiculous, and the fact someone broke it down is awesome!

The state of the art high tech proposal is to grind everything to a powder, put that in a high temperature plasma furnace for demolecularization, then extract raw materials for reuse. This kind of process would in theory result in waste dumps being seen as excellent competitive sources of materials such as gold and rare earth elements.

Turns out, it is very hard to get to the sun.

That idea reminds me of Patrick Star's solution to escape the terror of the Alaskan Bull Worm (Take X and push it somewhere else).

Wouldn’t composting have the same issue as tossing it in the dump though?

Landfills are actually better, in that in many cases commercial operators can recover the gas and turn it into renewable fuel.

There are now a few startups trying to make home/DIY anaerobic digesters that you can collect the gas from. Would be interesting for e.g. keeping a greenhouse warm year-round without the electricity spend.

For example (I have no idea how competent the product is): https://www.homebiogas.com/Products/HomeBiogas2

Put a compost pile inside your greenhouse and you get warmth and CO2 for your plants: https://www.lowtechmagazine.com/2015/12/reinventing-the-gree...

This is of no use in the developed world for a normal house. Try getting your home owners insurance to pay off a claim against an accident involving this. Also, according to its specs you can get 2hrs of cooking per day if you supply 5 gallons of animal manure. That's a tiny amount of energy compared to modern energy needs.

For most people this would be a novelty, maybe you could run an outdoor grill off of it.

I'm sure most families can gather 5 gallons of organic waste per week, which would provide them enough gas to have a BBQ once a week.

In a landfill, only anaerobic bacteria can survive. These are unable to break down organic material as cleanly as the aerobic bacteria in a managed compost pile. See my comment at https://news.ycombinator.com/item?id=21483584 for links to sources.

Aerobic vs anaerobic decomposition produces different byproducts.

Manure is pretty manageable, transportable, etc., are they can they use this to produce energy rather than just let it dissipate into the atmos?

They can; this is generally referred to as "biogas" (https://en.wikipedia.org/wiki/Biogas). It's equivalent to Carbon Capture and Storage, but for all of these methane releases. It's only used on a relatively small scale in rural areas, mainly to save money on natural gas (which is also basically just methane) and its related distribution infrastructure; I haven't heard of any successful projects to harvest biogas on the large scales required to really cut down agricultural and landfill emissions. The main challenge seems to be purification, as biogas has all kinds of nasty contaminants that are bad for people and machinery.

That sort of undermines some of the carbon arguments used against recycling.

Maybe, maybe not. Some of the things we recycle (metals and plastics) aren't biodegradable and hence won't release methane if dumped in the ground.

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