Removal of mercury from gas streams by oxidative membrane gas absorption

Citation
R. Van Der Vaart et al., Removal of mercury from gas streams by oxidative membrane gas absorption, J MEMBR SCI, 187(1-2), 2001, pp. 151-157
Citations number
13
Categorie Soggetti
Chemistry,"Chemical Engineering
Journal title
JOURNAL OF MEMBRANE SCIENCE
ISSN journal
03767388 → ACNP
Volume
187
Issue
1-2
Year of publication
2001
Pages
151 - 157
Database
ISI
SICI code
0376-7388(20010615)187:1-2<151:ROMFGS>2.0.ZU;2-N
Abstract
Mercury is a hazardous chemical that is present in a variety of gas streams . This work focuses on the removal of mercury from waste-incineration and s oil thermal treatment off-gas, natural gas and the glycol-overhead in a nat ural gas dryer by oxidative membrane gas absorption (oxi-MGA). The mercury in these gas streams is merely present in the metallic form. Suitable oxidisers were selected and the stability of several oxidiser-memb rane combinations was tested by a static immersion method and by monitoring the temporal development of mass transfer for SO2. It was concluded that P TFE membranes are needed for this application. Furthermore, the mercury mass transfer was studied. It was found that mass transfer is limited by diffusion in the liquid phase for relatively weak ox idisers and by reaction kinetics or diffusion through the membrane for stro ng oxidisers. With the generated mass transfer data, the required membrane area and investment costs were estimated. Finally, the precipitation of mercury sulphide turned out to be the most su itable method for regeneration of the absorption liquid. It was calculated that in the case of glycol-overhead treatment, the costs for regeneration o f the absorption liquid are negligible compared to the costs of the absorpt ion process. (C) 2001 Elsevier Science B.V. All rights reserved.