The Acme coke plant was a vital part of steel making operations on the south side of Chicago, Illinois for most of the 20th century. The coking process involves baking coal in huge ovens to reduce it to a more clean and efficient burning composition, which is then ultimately used as a fuel and reducing agent by blast furnaces. These massive furnaces once lined the shores of Lake Michigan below Chicago, but beginning with the closing of Wisconsin Steel in 1980, all have been shut down and subsequently demolished. The closest ones remaining are located at U.S. Steel in Gary Indiana and are still in operation.
Constructed over the years 1905 through 1929, the Acme coke facility mainly consisted of two oven batteries, containing about 50 separate ovens inside each, as well as 15 brick buildings and a wooden quenching tower. The coke was brought in by train to a rail dumper - this mechanism would lift an entire rail car and turn it over to deposit the coal onto a conveyor belt. The coal was then fed into the ovens and baked for about 19 hours; when the process was complete, enormous machines called "pushers" would then open the side of the oven and literally push the load of hot coal into a quenching car. This car was then doused with water in the quenching tower, and the coke was cooled further along a wharf. The Acme plant produced an average of 1,530 tons of coke each day, and employed around 250 workers. In 1958, a bridge was constructed to transport materials between the coke plant and the blast furnaces over the Calumet River. This 400 foot long suspension bridge brought the coke on a conveyor belt and delivered coke oven gas to the furnace, as well as moving process steam back into the coke plant.
Although the coke ovens were purported to last until 2015, they went cold when the plant shut down in 2001. When a coke oven goes cold, the inner lining of brick falls apart and is essentially ruined. Chicago's one and only suspension bridge - the Acme conveyor - was demolished in 2005; pieces of it reportedly crashed down onto the road as it was being dismantled.
Chicago’s Steel Heritage Project has been trying to preserve the site since it closed, hoping to convert the site into a museum. A salvage company had begun to tear away at the plant until the coalition stepped in and offered to pay $250,000 for the site - roughly the earnings that would have been made scrapping the metal and brick. The salvage company tore down the Acme blast furnace in 2004; it was the last remaining in the area. The museum would focus on the steel making process, history of the area, and the labor in cleaning up the site. They are looking at former steel mills that have gone through successful reuse as inspiration, such as Landschaftspark Duisburg-Nord in Germany and the Sloss Furnaces in Alabama.
