Recent advances in natural gas hydrate carriers for gas transportation - A review and conceptual design

Abstract

Natural gas hydrate (NGH) is emerging as a new eco-friendly source of energy to replace fossilfuels in the 21st century. It is well known that the Natural Gas Hydrate contains large amount of natural gasabout 170 times as much as its volume and it is easy to be stored and transported safely at about –20℃ underatmospheric pressure due to so called “self-preservation effect”. The option of gas transport by gas hydratepellets carrier has been investigated and developed in various industry and academy. The natural gas hydratepellet carrier is on major link in a potential gas hydrate process chain, starting with the extraction ofnatural gas from the reservoir, followed by the production of hydrate pellets and the transportation to an onshoreterminal for further processing or marketing. In recent years, Korean project team supported by Korean Government has been working on the developmentof NGH total systems including novel NGH carrier since 2011. In order to increase the knowledge onthe NGH pellet carrier developed and to understand the major hazards that could have significant impact onthe safety of the vessel, this paper presents and evaluates the pros and cons of cargo holds, loading and unloadingsystems through the analysis of current patent technology. Based on the proven and well-known technologiesas well as potential measures to mitigate sintering and minimize mechanical stress on the hydratepellet in the self-preservation state, this study presents the conceptual and basic design for NGH carrier.