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by kzrdude 1212 days ago
Landfilling still seems very inefficient. As Sweden has done for a long time: what ever you put in "regular waste" goes to incineration. The heat is used for district heating. Remains from incineration can be landfilled. Exhaust gases are monitored and cleaned.

Regular landfills have thus been abolished, which is a success. It's a small step, but IMO a very notable achievement.

And it has outraged some that plastic "recycling" goes into the same system in many parts of the country. I don't mind in principle - it is their (local government's) system, they are tasked with being professional and disposing of collected plastic in the best way possible. If that's going to be burning with retention of heat, then that's acceptable.

1 comments

Burning trash produces CO2 and that needs to be factored in. My guess is that CO2 produced transporting waste to landfill is less than that produced by burning. With landfills, there is problem with food and wharf waste producing methane. Separating that out and composting it, which produces CO2, is solution that my city does.

Sending waste to well-run landfill feels wrong but can be best alternative. We should probably worry less about recycling plastic and more about making sure there is no litter.

However, incinerating waste produces heat/energy which would otherwise have been obtained from burning fossil fuels.

At the end of the day it is a complicated problem and the only real solution - consume less shit - is basically untenable, so :shrugs:

Any trash that will sit in a landfill will still produce emissions (especially methane) and may release a lot of that CO2 anyway due to decay.

Completely agree that plastic is fine to end up in landfills or to be burnt though.

> Burning trash produces CO2 and that needs to be factored in.

My understanding is that waste incineration includes co2 scrubbers to capture co2 so it isn’t released into the atmosphere.

Capturing CO2 from flue gas requires a lot of energy (for something like a coal fired power plant, it takes about 30% of the power plant's energy output to capture the CO2) and you still have to deal with the CO2 after you've captured it - what do you do with it?

The only way to sequester it is to inject into underground reservoirs, but that requires a very specific geology which very few places have.

You can liquefy it and sell it... but then it's typically going to get released to the atmosphere by the purchaser, not sequestered.

I am not an expert in waste incineration (although I am an expert in carbon capture processes) but I seriously doubt that they use CO2 scrubbers. Scrubbers for other nasty molecules like SO2, sure, but the CO2 is probably just sent out into the atmosphere.

More likely SO2 scrubbers. Incinerator scrubbed CO2 would be incredibly dirty for most industrial CO2 uses.
The purpose is not to reuse the co2 but to prevent it from entering the atmosphere. And there are co2 scrubbers on waste to energy plants.