Thanks you very much for the quick reply. The water in question is a condensed water that contains up to approximately 1,000 chlorides and a few millimoles of both CO2 and H2S. It is a system that produces bas and liquid hydrocarbons. I believe that I can get some of the dissociation/complexation data that I will need. Many thanks again. Regards, Al ----- Original Message ----- From: David L Parkhurst <dlpark@xxxxxxxx> Date: Tuesday, July 9, 2002 7:41 pm In-Reply-To: <001801c2272e$5708f960$763c090a@xxxxxxxxxx> Subject: Re: Fw: Question on PhreeqcI and glycol > > > Is there a way of using PhreeqcI to model the interaction of a > relativelylow solids brine containing both CO2 and H2S, plus some > glycol? I am > interested in modeling the behavior of such a brine vs. > temperature and > pressure, to determine the extent of degradation of the glycol. > > I'm not sure what you need. PHREEQC is not good with high ionic > strengthwaters, say 1 molal and greater. On the other hand, I'm > not sure what part > of the thermodynamics you need. If it is just solubility of gases, > it might > be adequate; it has a linear log activity coefficient expression for > uncharged species. Charged species will get more unreliable the > higher the > ionic strength. PHREEQC has no explicit pressure dependence in the > aqueousmodel, but it is possible to specify partial pressures of > ideal gases. I'd > be reluctant to push things past a few atmospheres total pressure. You > would have to define a new "Element" glycol and any > dissociation/complexation that are pertinent. If you are trying to > do all > this a priori, I suspect you can't do it. If you are trying to > model some > experiments, you may be able to use some of the features of PHREEQC. > > David > > David Parkhurst (dlpark@xxxxxxxx) > U.S. Geological Survey > Box 25046, MS 413 > Denver Federal Center > Denver, CO 80225 > > Project web page: http://wwwbrr.cr.usgs.gov/projects/GWC_coupled > > > >
Please note that some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented prior to final review and approval by the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user.
Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government.
The URL of this page is:
Last modified: $Date: 2005-09-13 21:04:21 -0600 (Tue, 13 Sep 2005) $
Visitor number 1053 since Jan 22, 1998.