High-temperature-resistant plugging agent for heavy oil horizontal well and water plugging method

Abstract

The invention provides a high-temperature-resistant plugging agent for a heavy oil horizontal well and a water plugging method. The high-temperature-resistant plugging agent comprises water glass, urea and a filling agent, the volume ratio of the water glass to the urea is 1: (2-2.2), and the filling agent accounts for 20-25% of the total weight of the water glass and the urea. The residual plugging agent of the high-temperature-resistant plugging agent in a shaft can be treated through flushing operation, so that the construction safety is effectively ensured, and the construction process is simplified. The invention further provides a heavy oil horizontal well water plugging method, according to the method, the high-temperature-resistant plugging agent serves as a near-well section plug, a nitrogen foam gel plugging agent serves as a far-well section plug, and the water plugging effect of the horizontal well is guaranteed through cooperation of the two plugging agents. Compared with other water plugging methods of the high-temperature-resistant plugging agent, the high-temperature-resistant plugging agent and the water plugging method have the advantages of being wide in material source, safe and simple in construction, good in water plugging effect and wide in application prospect.

Description

technical field

[0001] The invention relates to the technical field of petroleum exploitation, in particular to a high-temperature-resistant plugging agent and a water plugging method for heavy oil horizontal wells. Background technique

[0002] Horizontal wells are mainly used for inter-well infilling of heavy oil and secondary evaluation of low-grade reserves in old areas, layered development, and secondary development. They have the characteristics of complex geological conditions, various types of reservoirs, and wide application types. However, with the increase of production rate and the decline of formation pressure, the problem of edge-bottom water invasion gradually intensifies, and the phenomenon of high water content in the produced fluid or even water flooding is common, and the water flooding problem gradually spreads to adjacent wells in the same layer, causing Water from vertical or horizontal well areas. After the water breakthrough in the horizontal well, t...