A method for separating lighter components of a hydrocarbon product in a container tank includes introducing the hydrocarbon product into the container tank via an inlet located near or at the bottom of the container tank; routing the hydrocarbon product through a pipe-in-pipe conduit that is at least partially surrounded by a bulk fluid stored in the container tank; providing a vapor-liquid interface that allows efficient evaporation of the lighter components resulting in separation of the lighter components and a processed hydrocarbon product; and routing the processed hydrocarbon product into the annular space of the pipe-in-pipe conduit thereby thermally insulating incoming hydrocarbon product from the surrounding bulk fluid and eliminating or minimizing vapor liquid equilibrium shift of the incoming hydrocarbon product caused by increased head pressure and/or reduction in temperature of the incoming hydrocarbon product.