Natural gas foam stabilizer system and preparation method thereof

Abstract

The invention discloses a natural gas foam stabilizer system. The natural gas foam stabilizer system consists of the following components in percentages by mass: 22.7%-56.8% of nano particle dispersion liquid, 0.006%-0.01% of a surfactant and 5,000-100,000 mg.L<-1> of mineralized water. The invention further discloses a preparation method of the natural gas foam stabilizer system. The preparationmethod comprises the following steps: adding NaCl or CaCl2 in water at normal temperature, stirring uniformly and preparing into the mineralized water; taking various components proportionally; addingsodium alcohol ether sulphate with EO number being 3 at first; and then adding nano SiO2 particle dispersion liquid, and stirring uniformly to obtain a natural gas foam system. The surface-modified positively charged nano SiO2 and the sodium alcohol ether sulphate as a negative-nonionic surfactant with the EO number being 3 have remarkable synergistic effect, the natural gas foaming ability can be improved, the natural gas foam stability can be greatly enhanced, and application of the natural gas foam system in tertiary oil recovery of oil-gas field development is greatly promoted.

Description

Technical field [0001] The invention relates to the field of oil field chemistry, in particular to a natural gas foam foam stabilizer system and a preparation method thereof. Background technique [0002] At present, in the development process of oilfields in my country, gas flooding is one of the commonly used enhanced oil recovery techniques. However, due to the higher gas mobility and the heterogeneity of the oil reservoir, the phenomenon of viscous fingering is prone to occur, which leads to relatively high oil recovery. The low sweep coefficient has limited effectiveness in enhancing oil recovery. As a gas-liquid two-phase mixed fluid, foam tends to show high apparent viscosity in formations. Moreover, the foam can seal the high-permeability layer and improve the sweep coefficient of the low-permeability layer; it will burst when encountering oil, and be stable when encountering water, and it has the performance of selectively blocking oil and water. Therefore, in the case ...

AI Technical Summary

Problems solved by technology

However, with CaCl 2 The addition of SDS / SiO 2 The foaming volume and stability of the system are reduced, and the hydrophobically modified nano-SiO 2 Both the SDS head group and the SDS head group are negatively charged, and there is an electrostatic repulsion between the two, which will offset part of the attraction between the two and weaken the nano-SiO 2 Adsorption at the gas-liquid interface, which in turn affects the stability of the foam

At present, the foams studied at home and abroad mainly focus on the foam system formed by air, nitrogen, carbon dioxide and flue gas, but there are few reports on the natural gas foam system and its stability.

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