A man who paves India's roads with old plastic

Lignin from hemp could be a possible bitumen replacement:

https://gizmodo.com/a-compound-from-plants-could-replace-bit...

Looks like hemp is 5-30% lignin depending on the type, with female hemp having roughly double the lignin content by dry weight:

https://www.sciencedirect.com/science/article/pii/S223878541...

https://www.hempbasics.com/hhusb/hh3fiber.htm

Also algae oil can be converted to a bitumen-like tar with roughly 55% efficiency, so if we assume the best algae is 50% oil by weight then we end up with about 25% tar by weight (I can't find confirmation of this, so they might mean 55% tar from algae directly):

http://news.algaeworld.org/2015/04/algae-bitumen-could-soon-...

Perhaps these could be combined with recycled plastic to make an asphalt derived purely from biomass and recycled materials.

While I applaud the change in perspective into looking at plastic as a resource, not a curse, this article smells of BS:

> He received a patent for the process in 2006. Since then, almost 10,000km of Indian roads have been paved using his technique.

This sounds like random stats thrown around by government officials, particularly because later in the terribly-written article, it mentions:

> Nonetheless, at least 16,000km of road have subsequently been paved in the state of Tamil Nadu. The national government has since approved the idea and sanctioned at least 13,000km across the country to be paved in the material as well. Of this, 8,600km have already been completed, says Dr IK Pateriya of the rural development ministry in Delhi.

The numbers simply don't add up.

> Shredded plastic below 70 microns (including the multi-layer plastic shreds) is then sprinkled over it.

A shredder capable to shredding materials down to 70 microns is absurdly impressive, and would likely cost hundreds of thousands of dollars. Unless the article means that some of the plastic films being used have a thickness of 70 microns. Honestly, it just looks like the author read 70 microns in the source material and threw it in to impress without knowing what it means.

> A stone tile measuring one square metre has a manufacturing cost of Rs 100, approximately £1.. 60 plates would be sufficient to construct an eco-friendly bathroom, says Dr Vasudevan.

£60 to build a toilet in India, plus labor, construction, etc? This is a very bad idea. The median household income per capita in the poorest states in India is under $1000/year. Just the cost of the toilet is much higher than the median monthly household income of one person.

That's before we get into the issue of using cement and concrete in the "plastone", which are very carbon-intensive (concrete generates about 400kg of CO2 per cubic meter). It would be much cheaper, simpler and greener to use wood to build it, which can be carbon net-negative.

I found an interesting article that breaks down some of the potential problems with this process and the risks involved with heating plastics and trying to differentiate between plastic and PVC (they release different compounds when heated, both potentially problematic). https://www.thenewsminute.com/article/heard-about-miracle-pl...

I may not be fully understanding this, but isn't this process just going to make the Ocean plastic pollution a lot worse?

i.e.

Indian Monsoon Rains wear away the plastic from the road over few months, years....

The plastic particles drain and make it to the rivers.... eventually to the indian ocean...

... few years later, we now have large scale plastic particle pollution in the indian ocean thanks to this ingenious technique of mixing plastic with bitumen.

Little bit disappointing. Instead of 10 parts of bitumen, it requires use 9 parts of bitumen and 1 part of plastic. Add to that the heating of plastic to a tight upper bound lest it releases toxic fumes.

>> Plastic wouldn’t clog our oceans or our landfills if we didn’t throw it there in the first place.

The big worry isn't so much the oceans being "clogged." It's the microplastics. It's the tiny bits of plastic that bio-accumulate. The turtle choking on a plastic bag is one problem, the repercussions of plankton absorbing tiny beads of plastic into their cells another. Making roads out of bulk plastic doesn't help the microplastics issue. Spreading it out over thousands of miles of road may actually be worse than landfill it in a single place.

I seem to recall that asphalt may be ripped up and recycled -- I wonder if this stuff can be recycled the same way.

If anyone could help, I'm working with a company led by a young woman in Kenya who is actively creating paving bricks out of used plastic bottles. They need about $25k-$50k for machinery to help scale out the operation, and we're trying to find some people who can help secure this funding. Contact me if you'd like to help with doing something good with them.

Her company website: https://gjengemakers.wixsite.com/mysite

For this to work, the roads need to be better or same quality, and the usage of plastic needs to be more economically efficient.

Road quality being the same, the addition of plastic, including the labor, additional equipment costs of spreading it, storing it, producing it, must be cheaper than the cost of using just the bitumen.

Additionally, processing the recycled plastic has to be cheaper than just making new plastic for this process in the first place.

If this works out, it would be a good use of some waste materials.

> Since plastic coats the stone and interacts with the hot bitumen, it’s properties change and it doesn’t break down when exposed to light and heat.

This is a tall claim that needs substantiation. I'm no chemist, but I think most organic compounds, plastics included, break down with heat and light exposure.

Perhaps he thinks his process makes the plastic break down more slowly, but again, evidence needed.

I read recently about children getting cancer from sports fields made from recycled car tyres.

Do we not get to see a picture of such a road, or am I missing it?

plastic is disgusting. no matter however we disguise it.