Laboratory geochemical simulation

In order to extend relatively short-term laboratory experiments to timescales relevant to the storage process, geochemical simulations should be undertaken. Although such an approach will not represent all the complexities of the system, the simulations are valuable because they serve to highlight important features and feedback mechanisms. Various approaches have been used to model a reactive C02-formation water-aquifer mineral system, and only a brief description is presented here. 

Xu, T., E.L. Sonnenthal, N. Spycher and K. Pruess, 2004, TOUGHREACT user s guide A simulation program for non-isothermal multiphase reactive geochemical transport in variably saturated geologic media. Report LBNL-55460, Lawrence Berkeley National Laboratory, Berkeley, California. 

Sequestration of CO2 in a Depleted Oil Reservoir. This project will investigate down-hole injection of CO2 into depleted oil reservoirs in New Mexico. It will conduct a comprehensive suite of computer simulations, laboratory tests, field measurements, and monitoring efforts to understand the geomechanical, geochemical, and hydrogeologic processes involved. It will also use the observations to calibrate, modify, and validate the modelling and simulation tools. 

Wang Q. and Morse J. W. (1994) Laboratory simulation of pyrite formation in anoxic sediments. In Geochemical Transformations of Sedimentary Sulfur (eds. M. A. Vairavamurthy, M. A. A. Schoonen, T. I. Eglinton, and G. W. Luther, III, B. Manowitz). American Chemical Society, Washington, DC, pp. 206-223. 

Data from one of the laboratory experiments were used to develop and calibrate a geochemical model. This model was successful in simulating concentrations of O2, Fe, and As in leachate from other cores and may be suitable for modeling natural remediation processes in the contaminated aquifer. 

SCHOUTEN S., DE Graaf W., Sinninghe Damst6 J. S., VAN Driel B. G. and DE Leeuw j. W. (1994) Laboratory simulation of natural sulphurization II. Reaction of multi-functionalized lipids with inorganic polysulphides at low temperatures. Org. Geochem. 22, 825-834. 

Krein E. B. and Aizenshtat Z. (1995) Proposed thermal pathways for sulfur transformation in organic simulation macromolecules laboratory simulation experiments. In Geochemical Transformation of Sedimentary Sulfur, (eds. M. a. Vairavamurthy and M. A. A. Schoonen), VoL 612, pp. 110-137. American Chemical Society Symposium Series, ACS, Washington, DC. 

There are a variety of field and laboratory analytical methods for soil lead measurement, depending on the type of analysis and its purposes in a given evaluation. Bulk soil lead measurement refers to measurement of the total lead content of the soil sample. Chemical speciation and micromineralogical studies in the context of human lead exposure variability refer to amounts of specific chemical forms of lead and their geochemical states. These studies are sometimes done in tandem with relative bioavailability testings, i.e., amounts of lead being absorbed under in vivo or in vitro simulation of in vivo conditions (Casteel et al., 2006) with respect to Pb source attribution. Stable isotopic analysis studies deal with the quantitative stratification of lead s stable isotopic composition into the four main stable isotopes lead-204, lead-206, lead-207, and lead-208 (Gulson et al., 1995, 1997). 

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