Back in the days, long before The Sims was a thing, not to mention before the time that SimCity asserted its dominance over gaming communities all over the globe and inspired a lot of different, often peculiar Sim-style games, such as SimCopter, SimAnt, SimEarth, SimRefinery and SimGolf. SimRefinery may not be among the games that you know about because, as is stated on Wikipedia, the game was not released to the public. It was instead developed by a business-oriented branch of Maxis, meant for internal use at Chevron, the energy corporation.
Interest in SimRefinery was renewed in May 2020 when Ars Technica made a report on the in-depth history of SimRefinery on The Obscuritory, a site whose theme is to present some “odd, lesser-known games and software”. The actual game was, unfortunately, not available to play.
The Obscuritory wrote that nobody made an effort to keep and preserve the SimRefinery because, at the time, no one really gave it much thought and thought it was just an unimportant piece of software. It was just meant as a training program for an oil refinery in California and, to top all of that off, the training was not actually that successful. When you take all of Maxis into account, SimRefinery is one of their least important titles, which has now become an object of interest in the video game community simply because it is unavailable within the community.
Fortunately, the game was not completely lost. One Ars Reader managed to find and extract a working copy of SimRefinery and had the presence of mind to upload it to the Internet Archive. Obscuritory said in an update that the game is interesting, but the historical context around it must also be taken into account. It was released in 1993, just a few years after the release of the first SimCity and it shows that Maxis wanted to expand videogames beyond the normal sphere of interest.