Dividing wall columns for natural gas liquefaction plants

In order to meet current carbon dioxide emissions reduction challenges, natural gas processing and refining
industries have to find the ways to minimize energy requirements of distillation operations. Building on
foundations lied down in a preceding effort, this paper shows that this could be achieved in a cost-effective
way in natural gas liquids fractionation plants and that a conventional demethanizer column combined with
either a thermally coupled direct sequence of deethanizer and propane-butane recovery columns or a dividing
wall column produces expected savings in capital and hot utilities costs as compared to conventional direct
sequence, without any temperature penalty on cold utilities side. The choice between available options will
largely depend on important process considerations that may differ for offshore and onshore plants to the
extent depending on specific site requirements.