Riser [1]

A vertical pipe. 

In the petroleum marketing equipment industry, the term riser is applied to vertical pipes in a variety of applications. The pipe that projects out of an underground tank, and which is used for delivering product into the tank, will often be referred to as a fill riser or tank riser. A vent riser is the vertical portion of a vent line. A product riser is the vertical section of pipe under a dispenser.