... one discovers that there is something like a nozzle on its very top. This nozzle together with the extreme height gives a clue that something really nasty came out of here back in the good ol' days. Maybe the nozzle was fitted later to give some additional velocity to the fumes, sending them further away.

A not to far-fetched guess is that this is the vent from the viscose spinning process, where highly toxic (and foul smelling) carbon disulfide and hydrogen disulfide is released in large quantities. Simply fanning this out and pushing away through this tall stack was probably seen as the most effective way to solve the problem.

When looking a bit even closer, one can see that there are serious cracks and even holes in the concrete. Sulfur compounds mixed with humid air, forming corrosive acids is very aggressive indeed. I wonder how close it is to fall apart... Probably it does not matter as it will be blasted soon.

It appears like the only way up is via the ladder on the outside. Want to take a trip up to replace some faulty air-trafic warning lights maybe... ?