Regeneration and Reclamation of Mono-Ethylene Glycol (MEG) Used as a Hydrate Inhibitor: A Review

Abstract

The use of Mono-Ethylene Glycol (MEG) as a hydrate inhibitor in wet gas pipelines is increasingly becoming widespread, especially in deep-water long-tie back pipelines where the use of low dosage hydrate inhibitor (LDHI) is not practical. MEG is a commonly used thermodynamic hydrate inhibitor (THI), and it prevents hydrate formation by lowering hydrate formation temperature. One significant advantage of MEG over other THIs is that MEG can be regenerated and reused, which minimises the cost of chemicals as large volumes of THIs are usually required. Over the years, significant research advances have been made in MEG recovery and the MEG Recovery Unit (MRU) design. This paper presents a comprehensive review of the evolution of MEG regeneration systems over the years and introduces recent developments, particularly on energy conservation. The entire MEG recycle and regeneration process is reviewed as well as the various sections and their functions. The different MRU configuration are discussed and factors that affect the performance of the MRU as well as Corrosion and corrosion mitigation in the MRU. This review shows that there are a number of new improvements in the MRU application that are yet to be fully explored as well as some technical challenges that are yet to be fully understood.