Flow charts are a type of graphic organizer used universally to show structure, organization, and sequence of systems, jobs, events, and processes. Unlike other refineries, Valero in Corpus Christi refines residual crude, which is the thick, dark, heavy product left over after other refineries have extracted all of the lighter weight molecules to make gasoline and petrochemical feedstocks. Instead of burning it up as a waste product, Valero in Corpus Christi uses some highly specialized equipment and processes to further refine the residual crude oil into useful products including reformulated gasoline. This is the type of gasoline that is now required for use in many areas of the country, and the Valero plant in Corpus Christi was producing it six years before the government required that all refineries begin producing it. Like most refineries, Valero Refinery, Corpus Christi operates around the clock every day of the year.
People work in shifts to keep the plant running at maximum efficiency twenty-four hours a day.
It is called a flow chart, because it shows the direction of flow of the product. It was created by an engineer at Valero so that anyone can see the order of the steps in refining the oil. Here is another type of flow chart. This one doesn't show machines. It shows people.