Obiettivo The goal of this development project is to determine retention on the rock surface under simulated reservoir conditions. In the proposed investigation, retention data for both the individual surfactants and their combined mixture as well as data on the multichemical system containing both surfactants and polymers should be gathered and evaluated. Based on observations on linear flood tests it is presumed that, by post-flooding using additional surfactants and polymers, the retention of a surfactant mixture can be considerably reduced. This would result in a further reduction of the required concentration and slug size of the surfactant combination.The retention of the multi component system : petroleum sulphonate - non ionic surfactant in reservoir brine showed strong interactions and a high retention potential.It was found that adsorption of xanthan is not automatically high on surfaces with higher area. Here it is important that the adsorption sites are accessible to the macromolecule, which is obviously not the case for all sites of the reservoir rock. The reservoir rock has a specific surface of 2,6 m2/g, but only a small part of this surface seems to be accessible to the big polymer molecules. The major part of the specific surface measured with the very much smaller n-Heptane-molecules is contributed by a fine structure on the grain surfaces. Furthermore the adsorption sites of the reservoir rock, that was originally oil saturated and then cleaned with solvents, seems to be less active than the adsorption sites on the clean quartz sand. Adsorption of xanthan was even higher on the quartz sand than on the reservoir rock sample.The results from experiments performed with glucose and pyruvate clearly show that adsorption is influenced by the pyruvate content of the molecule, which means that higher pyruvate xanthans have higher adorption, which in turn may also be an additional reason for the poor injectability that was found with these products. Unfortunately these products could not be tested in the micro-flow-calorimeter, as this requires a good injectability to avoid heat effects due to uncontrolled pressure increases.1. Development and optimization of the analytical process for specificaton of both the surfactant combinations and the multiple chemical system.The surfactants which are planned to be used in the field are technical products which contain a broad spectrum of compounds of varying molecular weight and reaction groups. In the past, different methods of analysis (infrared spectrography, UV-spectrography, two phased Titration, etc were attempted in the flood tests. The main problem is the chemical separation of the used components like a mixture of crude oil, brine emulsions.2. Static absorption testsThe identification of absorption isotherms on sand surfaces should supply information on the absorption characteristics of both the various components and the multi-chemical system.Pressure-free-floodingUsing a model sandstone core with a porosity of 20% and a permeability of 1000 md, pressure-free flooding can be done. The testing of the flood and displacement behaviour of the individual components, the surfactant combination, and the multi-chemical system is done in order to determine the retention behaviour and to show, if present, a chromatographic separation of the components.4. The sandpack flood-testsThe sandpack flood-tests serve mostly in showing possible chromatographic separation.5. High pressure floodingThe work on the high pressure flooding apparatus can be done as a supplement to the pressure-free flood tests; here the influence of pressure on the flood-behaviour of the chemical system can be tested under simulated reservoir pressures. Programma(i) ENG-HYDROCARB 2C - Programme (EEC) of support for technological development in the hydrocarbons sector, 1986-1989 Argomento(i) 1.5 - IMPROVED OIL RECOVERY Invito a presentare proposte Data not available Meccanismo di finanziamento DEM - Demonstration contracts Coordinatore PREUSSAG AG (EX SALZGITTER AG) Contributo UE Nessun dato Indirizzo ABTEILUNG FORSCHUNG ENTWICKLUNG POSTFACH 15 06 27 1000 Berlin Germania Mostra sulla mappa Costo totale Nessun dato
