Well, this is a weird one. A while ago, game historian Phil Salvador wrote an in-depth history about Maxis Business Simulations, a Maxis offshoot designed to apply gameplay concepts to real-world applications. One of the story’s focal points is a game prototype developed in collaboration with Chevron in 1992 called SimRefinery. It was never completed, and was presumed lost. Fortunately for all of us, that’s not where the story ends.
Ars Technica posted about the piece, and one of its readers happened to be friends with a retired chemical engineer. Long story short, that person had a copy of the mysterious game on a 3.5″ floppy disk. Better still, it worked. And, even better than that, they’ve decided to upload the game to the Internet Archive.
Keep in mind that this program was designed for chemical engineers and plant workers, and that it’s incomplete. Don’t think that you’ll be able to learn how to run a plant yourself, either. Its intent wasn’t to show the mechanics of how plants operate, but instead to show how various parts of a plant are connected and can affect one another.