| In this paper, the principal ingredient of profile control agent was prepared with PAM and calcium lignosulfonate through modifying and grafting. In the condition of thermal and catalytic, a new style gelling material was made by condensation between PAM and calcium lignosulfonate. The gel strength of this material is much more than that of PAM as it gelling under certain temperature. Fluid volume and cost were decreased by above method, so it's beneficial to popularization and application of the project.Grafting efficiency of PAM and calcium lignosulfonate can be determined by colorimetric analysis of iodine and starch. Supposing lmol calcium lignosulfonate reacted with lmol amide group, grafting efficiency of calcium lignosulfonate can be calculated. The condensation between PAM and calcium lignosulfonate was confirmed further.Cr6+ in K)2Cr2O7 was reduced to Cr3+ by organic compound and Cr3+ can be taken for cross-linking compound. Gelling time of profile control agent can be adjusted by regulating mass volume in redox system. This is convenient for in-site operation of profile control.The anticipate technical level of profile control agent are: gel strength is over 100000mPa.s, gelling time can be adjusted among 5～40h, core test confirm that plugging percent is over 99% and breakthrough pressure is over IMPa/cm. Micro-image of core show: the original big path in core was plug by gel, following water was forced to elude plugging region, new bypass formed, sweep efficiency of injected water is promoted.
|
PDF Full Text Request