At Toshimaen 3

カン・ペットボトル、　もえるゴミ、　タバコを入れないでください
カン・ペットボトル、　もえるゴミ、　タバコをいれないでください
Cans・PET Bottles, burnable rubbish, please don't throw cigarettes in here.

It's common in Japan to separate rubbish into burnable, non-burnable and recyclables. Japan burns a lot of its rubbish because it doesn't have much space to bury it. It even ships some rubbish overseas, and also makes artificial islands out of it, like Odaiba in Tokyo. Paper and foodstuffs are burnable, non-recyclable plastic are unburnable.