Separation of Natural Gas Using Dephlegmator Technology

摘要

Efficiency of thermal processes such as heat exchange and distillation are sensitive to temperature approach. This is important when process temperature deviate significantly from the surroundings. In natural gas processing, often at cryogenic temperature, improved efficiency reduces the operational cost of a plant. This paper presents dephlegmator technology as one contribution to improved efficiency. A dephlegmator, or reflux condenser, has the function of a distillation column inside the body of a heat exchanger. It removes heat continuously while separating a vapor into a light fraction at the top, and a heavy liquid fraction (in reflux flow to the incoming vapor) at the bottom of the unit, see Figure 1. Using compact heat exchangers, a large area to volume ratio is obtained, thus reducing the need for space and foundation. Despite these intriguing features, the technology has yet to be utilized in many fields where it is well suited. The authors believe that improved design and simulation capability will change this. Our contribution to the development of dephlegmator technology is both theoretical and experimental.