The Problems of Plastic Waste Streams
The Problem as I see it
Mixed waste garbage, seen on the streets of many countries, has become a huge problem for our world.
It gets blown about; washed into drains and blocking them; hindering sewerage treatment plants; ending up in water ways and the oceans.
It can cause injuries and death to wild life, both on land and in the oceans. Accumulating in street garbage, the plastic bags can contain other contaminants, including faeces, motor oils, food waste, body parts, opened and sharp tin cans, etc. Therefore the collection and recycling, if possible, of these plastic wastes is not an easy, simple process.
Sanitizing the Waste: The waste materials cannot be handled safely before hazardous items and contaminants have been carefully removed and separated. Mechanical methods of separation are already dealt with on an industrial scale. But what about the biological hazards? How do you render the plastics safe, so that no one handling it subsequently is in danger of disease?
More importantly, what processes could be adopted which don't require the supply of enormous amounts of energy or sophisticated machinery?
Thermophilic There are various operations around the world, where thermophilic composting is used to sanitize biological materials, e.g., Humanure, Bedminster. I suggest that research in this area, i.e., putting all the waste, including plastics, through the thermophilic process first, would be the most sensible and economical method of sanitizing. It could provide employment for large numbers of people, especially in developing countries.
As more and more research is done into recycling different groups of plastic material, the output will become more valuable, providing funds for the initial collection and processing.
As the waste plastics acquire a value, it will provide incentive for people to collect and return containers, bags and packaging immediately after use, thus preventing the street-wide accumulation in the first place.
A Measure of Hope and Sanity
I have just come across this Website, showing a very positive progress in Haiti.
The lastest reports I can find so far were written in 2012. Much might have happened since then, but if anyone has more information please feel free to share it in this Comments column.
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Local biological materials for filtration of grey water