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Plastic to Oil – Produces 80% Oil

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Re: Plastic to Oil – Produces 80% Oil

#161

Post by Retric »

kraquepype wrote: post #158
Retric wrote: post #154

Earlier quoted context omitted.

So using a dryer is better for the ocean than air drying, good to know.

I would think air (line) drying would be better in terms of microplastics, since there is no tumbling. Would it be safe to say that (mostly) frictionless line drying would shed fewer particles than tumble drying?

The dryer collects already loose or broken fibers in the lint trap for disposal. Air drying doesn’t which means those large broken fibers containing several orders of more magnitude more plastic than might escape from a dryer end up in the environment.

This is why new clothes result in dramatically more lint than old clothes by weight.

Re: Plastic to Oil – Produces 80% Oil

#162

Post by marcosdumay »

AuthorizedCust wrote: post #15
actionfromafar wrote: post #9

Earlier quoted context omitted.

Also, plastics can contain all sorts of nasty toxic surprises. Better to burn it at a centralized location with proper filtering and treatment than having little batches or mystery oil of varying quality and toxicity.

> Better to burn it at a centralized location with proper filtering and treatment than having little batches or mystery oil of varying quality and toxicity. If we can assure that the output meets a standard should we burn it, then certainly we should be able to assure the output meets a standard should we refine/convert it.

It's much easier to purify the burning waste products than raw trash. It is much less varied.

Re: Plastic to Oil – Produces 80% Oil

#163

Post by thomasjb »

This would be rather useful in remote locations which find themselves with surplus plastics (remote islands with no landfill options for example), surplus renewable electricity and big old diesel engines. Those are unusual circumstances, but they are out there, and if there were organisations willing to fund the electricity aspect, the issue of plastic litter could be reduced in many places (and that includes ghost nets and other seaborne plastic). The resulting oil could pay back some of the cost of production, and be sold at a discount to the heavy diesel engine users in the area, on the condition that they uprate their emissions equipment. This may or may not have helpful effects in local markets.

Re: Plastic to Oil – Produces 80% Oil

#164

Post by csours »

generalizations wrote: post #109

I remember nearly two decades ago a PopSci article about some guy who figured out how to use microwaves to convert plastic (any hydrocarbon) into oil and natural gas. More than enough to break even. He was converting tires and waste plastic. Nothing ever came of it - IIRC, ownership disputes with the partner, and eventually the patent got purchased by some random company and blackholed. Edit: found a source. Better t…

Just like the "water carburetor" and other miracles that never materialized, the problem is that the alternative is cheaper and simpler (which means cheaper).

It doesn't sound expensive to add water injection to an internal combustion engine, until you have to make it work in production, with end users.

YOU can make it work, because you are motivated, but what about the guy who buys it because it's cool and then forgets to fill the system. Sure it's easy to add programming to work around this condition, but is it easy to integrate and test?

Anyway, crude oil is very, very cheap, and very easy to integrate into a production process. Waste plastic in the recycling stream is dirty and heterogeneous in composition and size, which makes it hard to integrate into a production process. Not impossible, but more expensive, which means that no one will do it without outside compulsion (and maybe not even then).

Re: Plastic to Oil – Produces 80% Oil

#167

Post by perrygeo »

koheripbal wrote: post #128
ahmedk92 wrote: post #96

Earlier quoted context omitted.

Before looking, it will probably be more pollution.

There is a reason that portion of the crude oil was made into plastic, and not sold as oil or fuel to begin with.

My first thought was "what kind of oil?". It matters. The clean burning, energy dense stuff was turned into fuel from the start. The rest of it is barely fit for a cigarette lighter.

But beyond that, not all plastics come from crude oil directly. Many plastics, especially baggies and consumer plastics of the type shown in these photos, come from liquids that are removed from natural gas.

Either way, you're certainly dealing with a liquid hydrocarbon of inferior quality. And at the huge energy cost of having refined it twice. I'd be surprised if this provided any net-positive energy. And it's certainly a dirty burning fuel with low BTU per volume.

Why not just burn the plastic directly at this point?

Re: Plastic to Oil – Produces 80% Oil

#168

Post by [deleted] »

photochemsyn wrote: post #116

Some issues: 1) Says it draws 1 kilowatt constantly and 'begins to produce oil in one hour', while also only holding about 1 kg max of plastic. How long does it take to finish processing the 1 kg of plastic into the 0.8 kg of oil? Is this a reasonable overall energy-return-on-energy-investment (and see #2 below, it will take additional energy). 2) If this is producing a typical crude oil, is further refining needed t…

[deleted]

Re: Plastic to Oil – Produces 80% Oil

#170

Post by dehrmann »

ansible wrote: post #85

Sounds similar to the thermal depolymerization [1] developed by companies like Changing World Technologies. [2] That technology seems very promising, but they ran into a number of difficulties in practice. They build a plant to process turkey leftovers in Missouri, but the plant wasn't profitable, and the community complained about the smell. [1] https://en.wikipedia.org/wiki/Thermal_depolymerization [2] https://en.w…

I went down this rabbit hole for a bit. The only obvious issue seems to be that burying (or burning if you're Swedish) plastic is really, really cheap. For the turkey waste, we're already good at rendering animal remains, so there just isn't a need.
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