EXPERIMENTAL AND SIMULATION STUDY OF SCALE FORMATION IN A CARBONATE IRANIAN RESERVOIR

Water injection in reservoirs is done with the aim of primary or secondary recovery program to keep the reservoir pressure unchanged or to increase the recovery of the reservoir, respectively. Scale formation in these processes is a serious problem which could be caused mostly due to mixing of incompatible injection and formation waters mixing. Studying the super saturation conditions before injection process should be done before designing an injection process to prevent the scales obstacle the pipes, surface facilities and damage in reservoir rocks around the wells. In thispaper the effect of temperature, pressure and the injection and formation waters ratio on scale formation have been studied experimentally. The samples of waters belong to one Iranian carbonate reservoir. The results then have been checked with the OLI ScaleChem simulator. The calciumsulphate is the main formed scale which its amount increases with temperature and the ratio of formation to injection water. Comparing the experimental with simulation results shows the goodness of the simulator’s prediction on concentration of bicarbonate and sulphate and there is a weak match on bicarbonate concentration which is due to exit of co2 from solution.

Keywords:

Scale Formation , Incompatible water , Water Injection , Carbonate Reservoir