EFFECT OF CARBON-DIOXIDE ON RHEOLOGICAL PROPERTIES AND STRUCTURE OF POLYACRYLAMIDE SOLUTIONS

The effect of CO2 on rheological properties and structure of polyacryl amide solutions was studied as a function of pressure, treating time, polymer type and presence of inorganic electrolytes and natural format ion rocks. It was found that the serious deterioration of the solution viscosity can be attributed mostly to the change of the solution stru cture, while the actual molecular degradation plays negligible role in the process. The phenomena are explained by modification of the disso ciation equilibrium of polyelectrolytes in presence of high hydrogen i on concentration. The experimental results may contribute significantl y to elaboration of new stabilization concepts in special enhanced oil recovery technologies based on joint application of carbon dioxide an d polymers.