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by eddietejeda 1805 days ago
Plastics are petrochemicals, meaning they’re made by combining fossil fuels (usually fracked gas) with chemicals. Petrochemical plants are among the most polluting industries in terms of harmful air and water pollution, and greenhouse gases. In the US, most petrochemical plants are clustered in a low-income, largely Black area of Louisiana known as “Cancer Alley.” So from fracking, to chemical production, to petrochemical manufacturing, people and the environment are harmed—that’s not even counting the end of the plastics lifecycle, like ocean pollution and incineration.

The concern:

https://www.scientificamerican.com/article/plastics-plants-a...

An insider view of industry:

https://www.mckinsey.com/industries/chemicals/our-insights/p...

My source: my wife is an environmental lawyer who is very concerned about climate change and works closely on these issues.

1 comments

Is it possible that plastic pyrosis powered by renewable sources will one day be economical?

For example: https://www.youtube.com/watch?v=qPIHJRIpLRk

This is an old video of a tabletop model. It runs at 1Kw/hr and takes ~3-4 hours to convert 1 kg of plastic into ~800ml of fuel.

The machine is really just a demonstration unit for their bigger models. I always wondered why don't we just use these machines in a scaled up manner with renewable sources to recover the fuel to be turned back into plastics. I'm assuming its just a cost issue.

You can power the process using a feedback loop where a small amount of the output gas (prior to condensing into liquid form) is used to heat the plastic. There's videos on YouTube of folks rigging up a system in the back yard with basic pipes and drums, and obtaining usable output liquid fuel. You just need enough initial energy input to reach the target temperature, after which it can self sustain.

The issue with plastic pyrolysis is it's turning fossil fuels sequestered in plastic form back into burnable fuels that end up in the atmosphere, further contributing to climate change. A better option is to sequester that plastic permanently back in the ground again. Even landfill, using this lens, is a better option.

Thats why I talked about using renewable energy. If we could have a closed loop system where the plastic is turned into oil and then turned back into plastic, we could minimize excess plastic waste + not use any more oil from the ground.
Solving the wrong problem IMO - Even if you reach 100% efficient reprocessing a portion of plastic enters the environment on each usage cycle, and this is the problem we urgently need to solve.

Switching out to materials which decompose harmlessly is a better option all round, even if the energy costs are higher.