Last year my work took my to a small group specialized in engineering support for sulfuric acid plants, mainly those helping the mining industry have plants on hand for processing ore. You know H2So4, right?
Sitting in the office of one of most the senior guys there, who I definitely respect, a huge yet well-worn and sticky-tabbed book caught my eye. It was the Handbook of Sulphuric Acid Manufacturing, Second Edition, by Douglas K. Louie, P.Eng. You can read about it here. The book covers everything from simulations to maintenance, written by a man who's been doing it his entire professional life. This was a go-to resource for even the top people in the office, and a great learning resource for the younger engineers.
Asking about the book also lead me to a favorite haunt of the office, sulphuric-acid.com. Part technical manual, part suppliers resource, part repository of standards and maintenance tips, it's a great site. You might even want to check out their brief articles on utilities like cooling towers and instrument air, even if you don't care about this industry.
Bonus: Sulphur or sulfur? Many formal groups like the IUPAC have ruled that "sulfur" is officially correct, yet you'll still see the "ph" spelling quite often. If in doubt I'd pick "sulfur," but if a plant or company is already using "ph" you're not going to be able to change it.