Molecular compound surfactant and preparation method thereof

Abstract

The invention relates to a molecular compound surfactant and a preparation method thereof. The molecular compound surfactant respectively comprises the following components and weight percent thereof: 20 to 40 of petroleum sulfonate surfactant, 6 to 30 of surfactant, 5 to 10 of high molecular modifier, 1 to 5 of viscosity reducer, 1 to 5 of additive and water added to 100. The preparation method comprises the following steps that: the petroleum sulfonate surfactant, the surfactant, the high molecular modifier, the viscosity reducer, the additive and the water are added into a reactor with a stirring device according to the weight ratio and are stirred at room temperature for 1.5 to 2.5 hours so as to obtain a finished product. The compound surfactant is prepared by utilizing a plurality of associations of structure complementary and good compatibility as well as the mechanism of intermolecular interaction of the surfactant of a plurality of association and active components with complemental structure and well matching, and the system has the properties of high-temperature resistance, salt resistance, high-viscosity resistance, ultra-low interfacial tension and the like, conforms to the requirement of environmental protection and can obviously enhance the recovery ratio of crude oil after being used for the oil displacement of tertiary oil recovery.

Description

technical field [0001] The invention relates to three oil recovery enhanced oil recovery, in particular to a molecular compound surfactant and a preparation method thereof for enhancing oil recovery. Background technique [0002] After the primary and secondary extraction of underground crude oil, more than 40% of the crude oil remains in the formation; if the formation conditions are not ideal, even 80% of the crude oil remains in the formation after the primary and secondary extraction. At present, my country's major oil fields have entered a period of high water cut, and underground crude oil is in a discontinuous state of dispersion. The oil displacement technology mainly uses the synergistic effect of alkali, polymer and surfactant to achieve the effect of increasing oil and reducing water, and improving oil recovery. [0003] Alkali / polymer / surfactant ASP flooding system can greatly improve oil recovery, but there are also some problems in the process of large-scale in...

AI Technical Summary

Problems solved by technology

[0003] Alkali / polymer / surfactant ASP flooding system can greatly improve oil recovery, but there are also some problems in the process of large-scale industrial application: 1. The use of alkali will cause multivalent ion precipitation, Rock minerals are dissolved, thereby destroying the oil layer and oil well structure, seriously damaging the formation, and the pump barrel needs to be cleaned every 10-15 days, which increases the cost of oil production; 2. The presence of alkali will not only greatly increase the use of polymers, but also It will greatly reduce the viscoelasticity of the polymer, especially the elasticity of the polymer; 3. The use of alkali will also cause the produced fluid to be a W / O emulsion with high viscosity, which not only affects the productivity of the oil well, but also increases the difficulty of demulsification