A chimney is basically anything that vents hot gasses. So there are industrial chimneys for ovens and whatnot.

You are thinking of the classic brick chimney made on masonry that vents through a ceramic flue inside of the chimney.

There also are “prefabricated” fireplaces/chimneys that have a firebox(where the fire is suppose to be) made of steel and lined with heat tolerant mansonry panels which vents through a steel flue that is similar to HVAC duct.

The company manufactures the prefabricated fireplaces. I didn’t bother to read the article, but I am guessing their ovens for baking coatings had the fire due to lack of maintenance if there was not any other typical cause. There are fabrication facilities in other industries that need/want to have their oven vents inspected yearly for excessive fouling that can lead to fires, some insurance policies require or heavily encourage that.