An algebraic technique based on pinch analysis has been developed for the planning of non-conventional natural gas (NG) field development projects. The development of NG fields with high carbon dioxide (CO2) content has become increasingly common in the oil and gas industry. In such cases, the raw NG needs to be treated in situ for CO2 removal to meet the sales gas specifications before being sent to the onshore gas processing plants (GPPs). The captured CO2 can either be reinjected into the reservoir for permanent storage, or utilised for enhanced oil recovery (EOR), for which partial sequestration may also be achieved. These options create the need to develop systematic techniques to provide high-level decision support for field development planning. The algebraic technique developed in this work overcomes the limitations of a recently developed graphical technique (Foo et al., 2016), as it relaxes the previous simplistic assumptions on stream purity requirements. Two case studies are used to illustrate the methodology. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.