| 摘要 |
The invention relates to a method and an apparatus for the removal of polyvalent cations, in particular divalent cations, from mono ethylene glycol. Mono Ethylene Glycol (MEG) is used to prevent hydrate formation in pipelines transporting gas, condensate and water. It may also contribute to pipeline corrosion control. The invention describes a method for the removal of polyvalent cations from mono ethylene glycol, comprising providing a feed of aqueous mono ethylene glycol comprising dissolved gas and salts of divalent cations (rich MEG), heating the aqueous mono ethylene glycol to a heated mixture, causing precipitation of at least part of the salts and release of at least part of the dissolved gas, in particular carbon dioxide, separation of released gas from the mono ethylene glycol, separation of at least part of the precipitated salts from the mono ethylene glycol, distillation of at least part of the water from the heated mixture, to yield hot dewatered mono ethylene glycol (lean MEG), wherein a first part of the hot dewatered mono ethylene glycol is lead back to the aqueous mono ethylene glycol feed to provide at least part of the heat for heating the aqueous mono ethylene glycol. |
