At almost every By Product Coke Works, there is a bleeder stack. This stack is used to bleed off excess fuel gas that the works both generates, and consumes. Normally fuel gas is also pumped to the blast furnaces and other plants within a steel mill where all of this is integrated into one large millwork. At a stand alone coke works, excess, at Thomas at least, was also pumped out to the local gas untility where it would be mixed with natural gas and sold to customers when there was a demand. When the demand wasn't there, excess gas was "bled off" to a bleeder stack and burned. You've likely seen these at a refinery at night, a tall stack with a flame at the top. Thanks to the HAER project, the bleeder stack at Thomas we well photographed. And a .TIF file was available for the images, allowing me to zoom in very close and look at all the details. Including how the igniter worked with heating filiments over the top of the stack.
The igniter platforms and electrical gear at the top.
I started the project by scaling the photo, and then drawing the base up in CAD to be 3D printed so I could offer it for sale in my Steel Mill Modelers Supply Facebook store. It's the most complicated part of the stack, and jump started the project for sure.