Plastic cannot be burned, nor decompose. How can we humans simply get rid of plastic? Soon, piles of plastic will somehow stack up on Earth, we must act now!
Most incinerators can practically burn plastics and recover significant amounts of energy; but, the plastics containing chlorides- PVC- and those containing fluorides- like teflons relatives- should not be incinerated. The types #1 and #2 plastics can be recycled / down-cycled to other useful purposes. There are quite limited programs in USA to recycle the other plastics- those may be the ones that your question covers.
Don't worry dear, Global Warming will melt it all soon.
i'm not sure about plastic, but my chemistry teacher showed us that you can melt styrofoam with Acetone (same as nail polish remover). How cool is that?! 8D
Plastic is even easier than metal or paper to recycle, just put all of it in your recycle bin.
I saw something on TV about old computers and TV's and they have a recycling plant that takes the plastic and grinds it up so it can be melted down again and made in something else. They also recycle the glass from the TV's and old monitors. That's why they ask that people don't throw them in the trash to be taken to the landfill.