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Grapevine canes can be converted into plastic-like material that will decompose

sdstate.edu

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Re: Grapevine canes can be converted into plastic-like material that will decompose

#171

Post by toast0 »

yellowapple wrote: post #80
ars wrote: post #43

Earlier quoted context omitted.

> it sounds like I'm just describing something like petrol in a solid form at room temperature That's what plastic IS. That's why it sounds like it, because plastic is in fact solid hydrocarbon. So not only is it not farfetched, it exists today, which is also why incinerating plastic for energy is the best possible way to dispose it. You remove the plastic from the world, you reduce the amount of oil pumped for fuel,…

> It's one of those environmental slam dunks with zero downsides In relation to directly burning oil for fuel, yeah. In relation to other disposal methods, there's still the pretty major downside of being dependent on a non-renewable resource, in addition to… > (Before you ask: Modern incinerators do not release any toxins from burning plastic, none.) Greenhouse gas emissions are still an issue, though, no? Or do the…

If you were going to burn oil for power, and instead you burn used plastic that for power, greenhouse gas emissions from the burning are roughly similar. However, you skip the emissions from oil extraction and transport, assuming the plastic is burned close to its use / collection.

Re: Grapevine canes can be converted into plastic-like material that will decompose

#173

Post by gmac »

jon_adler wrote: post #159
mcv wrote: post #152

Earlier quoted context omitted.

Yeah, I still don't understand why brown paper bags aren't more standard for everything. I do see some manufacturers reducing plastic, fortunately. For example, my box of tea bags used to come wrapped in plastic, and now it suddenly doesn't, and I'm wondering why it ever needed plastic. But there's still so much stuff that comes wrapped in plastic, and often multiple layers of it. Just ban it. There are excellent alt…

Unfortunately, all the actual tea bags are usually plastic. The wrapping is probably a small percentage of the plastic in this product.

This is also an issue for microplastics ingestion. In the UK, teabags are increasingly made of PLA.

Re: Grapevine canes can be converted into plastic-like material that will decompose

#174

Post by privatelypublic »

dz0707 wrote: post #127
privatelypublic wrote: post #122

Earlier quoted context omitted.

30mpg, 10 miles, means two pounds of gasoline, 910grams, knock off or add 100g for ethanol per your preference, a google says about 5grams per bag, so nearly 200 bags. Nowhere close to 10k, but nontrivial. And, this gets reduced and sometimes outright negated if you reuse the bag. Doesn't mean we shouldn't evaluate if plastic shopping bags are the beat choice though. I don't think replacing them with store bought dog…

I think your math is wrong. Most of modern cars do up to 150g of CO2 per 100km, there are other emissions too, but they are in way smaller numbers.

Thats comically wrong. Human Resting metabolism is on the order of 20grams of CO2/hr.

See: https://www.sciencedirect.com/science/article/pii/S036013232...

As for a kilo of gas per 10 miles- see https://en.m.wikipedia.org/wiki/Gasoline - says 0.71-0.77g/mL, standard conversion table says 3.785L per gallon. (https://www.engineeringtoolbox.com/volume-units-converter-d_...), and finally- since we're comparing burning gas for a car vs using it in plastic: the figure of merit is petroleum usage, not greenhouse gas emission. Technically, plastic and gasoline aren't going to be 1:1. But that's not napkin math anymore unless you're a petroleum engineer/chemist.

Re: Grapevine canes can be converted into plastic-like material that will decompose

#175

Post by sircastor »

alexchamberlain wrote: post #148

The UK banned single use plastic bags at major supermarkets. We all moaned about it for a few minutes, forgot our reusable bags a couple of times and then got on with it. Even the small plastic bags you put fruit or pastries in are now gone in a few super markets - initially, they replaced them with transparent paper-based windowed bags, but then I think people realised you really don't need to see inside the bag, an…

Since all our local markets have introduced handheld scanners, I don't even bring my bags in. I put everything in the cart barcode up, get to the checkout, scan everything, pay, and go.

When I get to the car I unload into the bags. I'm sure it's not a thing for everyone, but I feel like I'm cutting out a fair bit of shuffling.

Re: Grapevine canes can be converted into plastic-like material that will decompose

#176

Post by sircastor »

mrmincent wrote: post #26

I would kill for this for when I’m buying fresh produce at the shops. Right now I just raw dog the produce into my basket as putting 4 apples into a plastic bag to ease the weighing and transport home seems like a selfish thing to do to the environment, but something that starts to break down soon after that sounds great.

We've got reusable mesh bags that we use for this.

Re: Grapevine canes can be converted into plastic-like material that will decompose

#177

Post by 2III7 »

sircastor wrote: post #175
alexchamberlain wrote: post #148

The UK banned single use plastic bags at major supermarkets. We all moaned about it for a few minutes, forgot our reusable bags a couple of times and then got on with it. Even the small plastic bags you put fruit or pastries in are now gone in a few super markets - initially, they replaced them with transparent paper-based windowed bags, but then I think people realised you really don't need to see inside the bag, an…

Since all our local markets have introduced handheld scanners, I don't even bring my bags in. I put everything in the cart barcode up, get to the checkout, scan everything, pay, and go. When I get to the car I unload into the bags. I'm sure it's not a thing for everyone, but I feel like I'm cutting out a fair bit of shuffling.

Why not have the bags in the cart and put the scanned products straight into the bags?

Re: Grapevine canes can be converted into plastic-like material that will decompose

#178

Post by behringer »

gmac wrote: post #173
jon_adler wrote: post #159

Earlier quoted context omitted.

Unfortunately, all the actual tea bags are usually plastic. The wrapping is probably a small percentage of the plastic in this product.

This is also an issue for microplastics ingestion. In the UK, teabags are increasingly made of PLA.

Time to switch to loose leaf tea

Re: Grapevine canes can be converted into plastic-like material that will decompose

#179

Post by mcv »

alexchamberlain wrote: post #155
mcv wrote: post #152

Earlier quoted context omitted.

Yeah, I still don't understand why brown paper bags aren't more standard for everything. I do see some manufacturers reducing plastic, fortunately. For example, my box of tea bags used to come wrapped in plastic, and now it suddenly doesn't, and I'm wondering why it ever needed plastic. But there's still so much stuff that comes wrapped in plastic, and often multiple layers of it. Just ban it. There are excellent alt…

I think banning plastic completely in packaging is a much harder ask, as whether it is needed is rather nuanced (if I understand it correctly). For example, it's perfectly possible to deliver cucumbers to an end customer without them being shrinkwrapped. However, to deliver enough cucumbers to enough customers for a supermarket scale, I understand from several documentaries that plastic is still required in that case…

Interesting thing is, the non-organic cucumbers at my supermarket don't come in plastic, but the organic ones do. I never know which ones to get.

Re: Grapevine canes can be converted into plastic-like material that will decompose

#180

Post by upcoming-sesame »

alexchamberlain wrote: post #148

The UK banned single use plastic bags at major supermarkets. We all moaned about it for a few minutes, forgot our reusable bags a couple of times and then got on with it. Even the small plastic bags you put fruit or pastries in are now gone in a few super markets - initially, they replaced them with transparent paper-based windowed bags, but then I think people realised you really don't need to see inside the bag, an…

For fruits and vegetables - Why is a bag needed at all ?

I just put my fruits and vegetables directly on the conveyor belt.

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