Burning Plastic in the Himalayas – A consideration of the options
Initially when I think about burning plastic… I think of stinky black toxic smoke belching out polluting the otherwise pristine air of the Himalayas. It’s is not the image I want to have when thinking about the majestic beauty of the world’s highest mountains. However, having now spent 25 years travelling and leading tours in the Himalayas, I’m sad to say that plastic is as much a problem here as it is in most other parts of the developing world. And contrary to some parts of the developed world, there is NO way to cleanly dispose of it.
Every single water bottle, chip packet, Maggi 2-minute noodle wrapper and shopping bag that gets used in the Himalayas stays there, lining the once pristine rivers, lakes, streams, pathways, campsites, towns, villages and hillsides.
If the plastic is dealt with at all, it is occasionally swept into a pile and burnt in the aforementioned black smokey way… Or thrown into one of the great Himalayan rivers with the salutation “Chello Pakistan” as it winds its way through valleys across the Indian subcontinent on its way to the ocean… Or buried in a small hole, only to be unearthed some time in the near or distant future.
But generally, its not dealt with at all… it’s thrown casually out of the windows of countless cars, buses and taxi’s by the very same tourists who paid good money to come and gawk at the wonderfully idyllic nature the Himalayas is famed for.
The endless number of food, drink and accommodation operators who service the rapidly escalating numbers of tourists have nowhere to dispose of the plastic they offer their clients, other than to chuck it into a hole or a barrel and throw a match at the stuff. Often the wind catches a hold of it before a casual flame does, and that same plastic is now spread far and wide throughout the mountains, adding to the splendour with its multi-hued colours that resist fading even in the relentless sunshine.
Walking along the spectacular shores of Pangong Lake straddling the Indo-Tibetan border at 4500m is now an exercise in deciding whether to spend the time picking up Bisleri bottles, Maggi packets and Coke cans, or to doggedly keep one’s gaze on the horizon, trying to avoid the inevitable horror of what lies at one’s feet.
So… is there an alternative?
Well, the obvious solution to the global issue of non-degradable plastics is that they shouldn’t be made at all. There are various biodegradable alternatives that could be used if plastic packaging is required. Unfortunately, these are not used in an extensive way as yet.
Enter the “Rocket Stove”. Used extensively in European and North American cold climate regions due to their efficient use of fuel, rocket stoves are a simple concept in combustion that combines clever airflow with an insulated combustion chamber to achieve high operating temperatures.
It’s these high temperatures that are interesting. In a normal rocket stove situation, high temperatures are used to combust smoke particles in a way that makes the stoves both efficient as well as pollution free. In most of my other ramblings about rocket stoves, it’s the efficiency that is the featured ‘feature’. In this case, however, it’s the lack of smoke that’s interesting. Pollution free combustion is an elegant idea that could be applied to plastic in a low tech scenario.
High temperature incinerators have been used around the world by nations trying to deal with the mounting issue of waste for many years. It seems that if one burns the waste hot enough, it no longer “pollutes”. What that means in practical terms is that the complex molecules that make up many plastics are reduced to simpler (and mostly) non-toxic molecules by the combustion process. All it takes is high enough temperatures. The temperatures used in a government waste treatment facility in the USA range from 1800 to 2200F (940 to 1200C).
A well designed rocket stove can achieve 1100C+ quite easily (I’ve had a small unit on my test bench running at 1150C) so with a bit of tweaking 1200C should be quite achievable. And it can be done with materials that are cheap and easy to find, it’s just a matter of design.
Even if these low tech stoves are operating just below the ideal temperature of 1200C, the alternative should be considered. Plastics anyway are being burnt in low temperature barrel fires all over the place creating no end of toxic black smoke that wafts through villages, towns and valleys. Even an imperfect high temperature combustion has to better than that.
As a result of this, the Himalayan Rocket Stove Project now has 2 distinct programs:
- The social enterprise metal box rocket that is designed to keep people warm in their homes with a minimum amount of fuel combusted cleanly (wood and/or dung)
- The non-profit project aimed at educating Himalayan locals in how to use clay to make cheap, reliable large space heaters and rocket stove furnaces designed specifically for burning plastic in a clean safe way whilst also providing heat energy for practical use (eg: warming communal spaces such as nunneries, monasteries, schools, village halls, etc as well as heating water for guesthouses, etc).
With regards to burning plastics cleanly, testing at the Ladakh workshop in Leh has recently demonstrated that a specialised insulated clay rocket stove can burn plastics with no noticeable smell or smoke. Further testing will show whether the optimal 1200 Celsius has been achieved. (Having burnt out my original high temperature probe, I’m currently waiting for a new batch to arrive.)
Meanwhile, as testing continues, we are excited at the prospect of converting a useless waste product into a highly sought after energy source.
Having posted some photos of the initial test burn on Facebook, I was since notified about the possibility of releasing toxic chemicals that fall into the Dioxin and Furan categories. There are over 200 such chemicals and are widely regarded as extremely noxious and highly persistent. These are generally released in low temperature fires such as those which commonly grace the back of households across the globe. There is some question as to what temperature range is considered safe for combustion of these chemicals. As a result I am looking for a suitable research and testing partner, possibly a university or research lab that is interested to be a part of this project to find a safe and affordable means to deal with the issue of plastic waste in the Himalayas. Any contacts in this regard will be gratefully accepted.