Oilfield Polymer Injection Post-polyelectrolyte Complex Is Further Enhanced Oil Recovery Research

The are very much residual HPAM in the oil deposit after the polymer driving having been performed. This thesis comprehensively analyzes the distribution of the residual HPAM, the physics alternation of the oil deposit and the residual oil, and thinks that the non-uniform of the oil deposit is augmented. When the water driving ,the permeability divergence is broadened, and can happen the finger scurrying. Based on the feature which has the negative electricity, so we proposes the polyelectrolyte complex technique, that is injuring cation polyelectrolyte and it can cross-link the residual HPAM which is remained in the oil deposit.The technique of supra-numerator after polymer driving ,is one that the cation Polyelectrolyte is mixed with the residual HPAM which is held up in the oil deposit, by the static electricity force in the aqueous solution. The result is that happens hydrophobe, forms stationary supra-numerator aqueous solution ,and the viscosity is increased. It can block up the high permeable bed which has more concentration HPAM, and make the following water go into the low permeable bed, broaden the spread effect, enhance the Exploitation effcent of the following water driving after HPAM driving. This technique has significant value in the future enhancing oil recovery after HPAM driving.①This paper synthetised two kinds of cation Polyelectrolyte, by AM , NAM , DMDAAC or DAC, in the way of two initiating procedure. The P(AM-NAM- DMDAAC) is better in stability and performance, whose molecular weight is 0.58 × 10~7,the cation content is 6.14% and the hydrolysis content is 3.5%. But, the P(AM-NAM- DAC) is bad in stability, it is stable only that the pH is less than 4, so it cant be used in the oil deposit condition.②When the P(AM-NAM- DMDAAC) and the HPAM is mixed in aqueous solution, we can find that the macroscopic form of the apparent viscosity will change. The mixed solution will be stable and the apparent viscosity is increased when the cation content is less than 6.14%, however it will precipitate when the cation content is more than 12.06%. And the precipitation will be dissolved in the aqueous solution which has SDS and salt. Because that the salt shields the static electricity force, and the SDS happens hydrophobe with the Polyelectrolyte, that can make the complex dissolve.③When the P(AM-NAM- DMDAAC) and the SDS is mixed in aqueous solution, we can find the critical aggregation concentration (CAC). When the concentration of SDS is less than CAC, the complex with P(AM-NAM- DMDAAC) and SDS is stable, and the apparent viscosity is increased , the shear degradation is dominated. So we make up the CFZ-300 with P(AM-NAM- DMDAAC) and SDS according to the optimum dispensation.