Agreed about every council making things up as they go along - you can put things in our recycling bins (e.g. tetrapak cartons) that neighbouring areas reject, and now everything goes into the one (grey) recycling bin - the green bin is for general refuse. Likewise we're told that the majority of sorting is now done my smart machine (but it can't cope with black food trays apparently).

Burning has a number of disadvantages. Plastics often produce nasties (e.g. chorine based compounds) that aren't at all easy to scrub out of the flue gasses - less of a problem if you're surrounded by thousands of square miles of mostly uninhabited sea and have a strong prevailing wind to carry the nasties away from what populated areas you have - less easy to handle in inland urban areas where there are major populations centres in almost every direction and air quality is already an issue. Also burning plastics just puts CO2 into the atmosphere pretty much like burning the original oil as a fuel - something that most authorities are doing their level best to reduce, not increase. Of course we'd do better to reduce the amount of unnecessary plastic packaging in the first place, but failing that re-using the materials in some way (hopefully many times over, but even a few times helps) seems like a reasonable option.

I agree that all the transportation can be an issue (especially when stuff ends up being shipped abroad to a dubious end) - hopefully in time more local uses for the materials could be found (but while we insist on importing many of our finished products from the opposite side of the planet - there is a certain inevitability that raw materials must make the opposite journey).

    - Andy.

Agreed about every council making things up as they go along - you can put things in our recycling bins (e.g. tetrapak cartons) that neighbouring areas reject, and now everything goes into the one (grey) recycling bin - the green bin is for general refuse. Likewise we're told that the majority of sorting is now done my smart machine (but it can't cope with black food trays apparently).

Burning has a number of disadvantages. Plastics often produce nasties (e.g. chorine based compounds) that aren't at all easy to scrub out of the flue gasses - less of a problem if you're surrounded by thousands of square miles of mostly uninhabited sea and have a strong prevailing wind to carry the nasties away from what populated areas you have - less easy to handle in inland urban areas where there are major populations centres in almost every direction and air quality is already an issue. Also burning plastics just puts CO2 into the atmosphere pretty much like burning the original oil as a fuel - something that most authorities are doing their level best to reduce, not increase. Of course we'd do better to reduce the amount of unnecessary plastic packaging in the first place, but failing that re-using the materials in some way (hopefully many times over, but even a few times helps) seems like a reasonable option.

I agree that all the transportation can be an issue (especially when stuff ends up being shipped abroad to a dubious end) - hopefully in time more local uses for the materials could be found (but while we insist on importing many of our finished products from the opposite side of the planet - there is a certain inevitability that raw materials must make the opposite journey).

    - Andy.

AJJewsbury said:

but it can't cope with black food trays apparently

I believe it can't cope with any black plastics Andy. That's the reason I've been told why we can't pop black plastic plant pots into recycling either.

Assuming the burning is used to generate power or heat we actually use, the CO2 generated is however similar to that not emitted by the gas or fuel oil that would have otherwise been burnt to do the same.

Yes PVC is a pain, burning can generate hydrchloric acid gas among other things, but the common domestic packaging materials of polythene and polypropylene are cleaner burning, but identification and separation is not made very easy.

The high temperature take-away style oven trays that go up to about 180-200C are typically airPEt or C PET and are polyethylene tetrapthalate, often  known as a type of  'polyester'. Now, when really clean it can actually be recycled quite easily but the problem is the contamination with food. On burning it does not liberate anything especially nasty but it needs a lot of air or it burns sooty.

More controversial are poly-carbonates, sometimes used for water bottles which can decompose to give BisPhenol, which has been linked to health problems, however it still burns nicely to C)2, water and some carbon black.

Compared to the tonnage of petrol burnt in the UK every year (ref  3000 million litres month, about 30 million tonnes a year, and more or less the same again with Diesel fuel. ), even if we burnt every scrap of plastic we had (ref ~ 5 million tonnes a year), so long as it was done properly in terms of pollution it would be quite a lot less.

Mike

Yes, I totally agree that burning all flammable  waste to save resorting of anything is ideal.  Metals, glass, ceramics and rubble are the only recyclables.  To this end we only need 2 bins one large for delivery to the base load power station which could deliver about 2% of our electricity and a smaller bin for metals glass etc. which can be sorted automatically on a conveyor belt with minimum human interaction.