Abstract
Background: Raw natural gas, one of the most important fuel sources worldwide, contains high level of CO2, which must be removed to avoid problems like pipeline corrosion, compression cost and reduction of heating value. The three main technologies used to separate CO2 from natural gas include cryogenic distillation, amine absorption and membranes. Membrane technologies have various advantages especially for offshore platforms. In recent years, more and more membrane systems have been applied to large offshore natural gas upgrading projects. Two entirely different membrane processes can be applied to the separation of CO2 from natural gas: gas permeation membranes and membrane contactors.
Objective: An overview of some recent patents and related scientific literature on both gas permeation membranes and membrane contactors for CO2 removal from natural gas is important to focus on the key points for further advances. Methods: From a thorough literature review of membrane processes for CO2 separation from natural gas, several patents on this application have been identified and here reviewed. Besides, recent papers in the field are discussed. Conclusion: Membrane systems require a relatively small operational area, small amounts of energy, only minor operational efforts with moderate maintenance and inspection requirements. Hence the interest from oil gas industry companies such as UOP, L’Air Liquide, Statoil Petroleum, Aker Process Systems, which are applicants and assignees of most patents for CO2 removal from natural gas by membrane technologies.Keywords: CO2 separation, gas permeation membrane, membrane contactors, membrane plasticization, membrane technology, natural gas, pre-treatment systems.
31
8
2
1