Studies And Applications Of Water-Rock Interaction For Super-Viscous Oil Reservoir

The development of super-viscous oil with steam stimulation is greatly effected by water-rock reaction under high temperature. In order to improve the development level, on the basis of geological condition, the development method and production performance analysis of Shu-1 Area, the X ray diffraction analysis for the cores and the ionic analysis for the formation water and the vapor condensed water were carried out. The interaction between the vapor condensed water and various minerals (such as quartz, feldspar, clay mineral,etc.) making up the cores under high temperature and pressure was studied using high-pressure reaction tank. The effect of factors including the concentration of NaCl, pH value and other additives on the reacting process between the vapor condensed water and various minerals was also studied. The results were used for filed application. Experiments show that the concentration of silicon in the formation water is less than 100 mg/L and its concentration in the vapor condensed water is greater than 100 mg/L. With the increase of temperature, the concentration of silicon in the vapor condensed water is becoming greater, on the contrary, the concentration of other ions is just the same. The concentration of clay material and montmorillonites is increased also. With the increase of NaCl concentration, the content of clay material after reaction is just changed a little. With the increase of pH value, the content of clay material and montmorillonites after reaction is greater than before. When the ammonium chloride is added into the reaction tank, the content of clay material and montmorillonites after reaction is less than before. The method of ions and silicon concentration monitoring can be used to determine the source of water. This method has been used in SHU1 Area and has achieved good results.