These refineries are not being permanently shut down.
The companies involved--more than one, if you'll notice--are in the process of trying to sell them to others who will then operate the refineries. If they can't sell them, then they'll be idled, but the Philadelphia one alone has four outfits interested.
This is called "business," and if it's a great price-hiking conspiracy, you'd think they'd be working with more than three or four of the 148 operable refineries in this country instead of a few refineries just in the Northeast.
Hint: three is 50 percent of what number? What percent of 148?
You don't seem concerned with the union strike mentioned in your article which could idle ten percent of the whole nation's capacity. Is that part of the "monopoly" conspiracy too?