Temperature-resistant salt-tolerant foaming agent carbon dioxide flooding profile control and preparation method thereof

Abstract

The invention belongs to the technical field of the chemicals in an oil field, which discloses a temperature-resistant salt-tolerant foaming agent carbon dioxide flooding profile control and a preparation method thereof. The foaming agent comprises 15-30% of anion-nonionic surfactant host, 6-20% of nonionic assistant foaming agent, 2-5% of organic micromolecule foam stabilizing agent and 50-77% of water. The preparation method for the temperature-resistant salt-tolerant foaming agent carbon dioxide flooding profile control comprises the following steps of: adding the anion-nonionic surfactant host and water into a reaction kettle in sequence; heating to 40-60DEG C, stirring and dissolving; then adding the nonionic assistant foaming agent; after the nonionic assistant foaming agent is dissolved, continuing to add the foam stabilizing agent to stir; and evenly dissolving to obtain the product. The foaming agent disclosed by the invention is suitable for the carbon dioxide flooding plugged channeling profile control under the geological conditions that temperature is not higher than 110DEG C, and the degree of mineralization is not higher than 150000ppm.

Description

technical field [0001] The invention belongs to the technical field of oilfield chemicals, and relates to a chemical additive used in oilfields to improve oil recovery efficiency and a preparation method thereof, in particular to a temperature-resistant and salt-resistant foaming agent for carbon dioxide flooding profile control and a preparation method thereof. Background technique [0002] With the expansion of demand for oil and gas resources in social development and the continuous depletion of easy-to-recover oil reservoirs, after primary and secondary recovery, the current tertiary oil recovery technology has achieved great development. Due to its unique oil displacement principle, the carbon dioxide flooding technology has great application potential in the tertiary oil recovery engineering of high temperature, high salt, low permeability and heavy oil reservoirs, and has gradually developed into a major technology in the world. means of tertiary oil recovery. [000...

AI Technical Summary

Problems solved by technology

[0005] Although a small amount of research and development work has been carried out on foaming agents for carbon dioxide flooding profile modification in China, the foaming agents used in other fields of oilfields are mainly screened and evaluated directly under carbon dioxide flooding conditions, so there are obvious limitations, such as the usual The temperature and salinity of the carbon dioxide flooding block are higher, and the degradation rate of conventional foaming agents in high-temperature reservoirs is faster, which cannot meet the application requirements; in solutions with higher salinity, most of the conventional foaming agents will form precipitates or cannot be dissolved, and the final foam cannot be formed; at the same time, when carbon dioxide is used as the foaming medium, due to the influence of the high solubility of carbon dioxide in the water phase, the stability of the foam formed by ordinary blowing agents will be significantly reduced