Does anyone know what these chimneys are.

I live in a flat in south london and can't help but notice these along side huge ship mounted cranes. I couldn't find anything on the news because i couldn't be bothered to google it. Does Anyone know anything.

https://preview.redd.it/ya41o3ter7pe1.jpg?width=1080&format=pjpg&auto=webp&s=89deaf4bfc0c32bc87f10aea7a53fcd40f24f945