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by snarf21 2091 days ago
It makes more sense for dense cities but I think we really need a way to not have to ship this trash everywhere. I don't know if it is feasible but some kind of small scale incinerator seems ideal. You convert your trash into power and we don't waste a lot of energy moving it all over the place. This could also be a source of energy that works when solar isn't available.
1 comments
shash 2090 days ago
The thing is, cogeneration (incinerators producing power) is a bit of a red herring; usually our waste doesn't have the calorific value to actually produce usable power, so it's mixed with fuel, which is not exactly ideal. Also, unsegregated garbage, when burnt, will produce stuff like dioxins and furans which you don't want in the atmosphere.

It's necessary for some types of waste (medical, for example), but it's not a power generation method.

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mschuster91 2090 days ago
> Also, unsegregated garbage, when burnt, will produce stuff like dioxins and furans which you don't want in the atmosphere.

Modern garbage power plants have enormous exhaust filtration systems that take care of pretty much any toxic contaminant, no matter its form.

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shash 2089 days ago
Assuming that the filtration systems are working perfectly, and are in order all the time. That’s not trivial...
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mschuster91 2089 days ago
In Germany the operators are bound by law to monitor their systems and fines are steep.
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shash 2088 days ago
Germany might be the only place where this tech is working as advertised.

This stuff needs to work on a planetary level to make a difference. “Just solve corruption and this will work” is a kind of complex way around it...

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TeMPOraL 2090 days ago
That doesn't feel right. Looking at the typical household production, I see (after separating out metals) mostly plastics, wood, paper, and various oils. This should all burn nicely and have high caloric value.

Agreed on the toxic combustion products, though.

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shash 2089 days ago
Not enough to make up the difference. Definitely not as much as coal or fossil fuel for example. Sure, they’ll burn, but not hot enough. Most domestic waste has a calorific value of not more than 16 MJ/Kg, and you need at least 15 MJ/Kg for ignition. Meaning, you need to add some other fuel to make it burn. Coal for comparison gives off 15-30 MJ/Kg, so it’s right on the edge there. Industrial waste is a different ball game, but then industrial waste has lots more toxic stuff.

Source: http://www.igniss.com/calorific-value-waste

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