Bitumen heating is very tricky because it is usually very think and heavy. The heaters used for bitumen are usually those that are used for tank heating because bitumen is typically stored in bitumen tanks.
There are two types of bitumen that would determine how heating is applied and what type of heaters are used. The most common form of bitumen is the crude type, i.e. a tar-like petroleum that is sticky and naturally occurring. There is also the refined type, also known as residual, which is basically a left over fraction. While both types are think and heavy, the refined is the heaviest and has the highest boiling point.
Also read: Why bitumen needs to be heated?