Low-permeability reservoir water-lock releasing agent and preparation method thereof

Abstract

The invention discloses an oil field chemical agent used in petroleum gas oil-pumping operation construction, and particularly relates to a low-permeability reservoir water-lock releasing agent used in working fluid and a preparation method thereof. The low-permeability reservoir water-lock releasing agent consists of the following components in percentage by weight: 1 to 15 percent of glycol ether, 15 to 45 percent of didodecyl dicarboxylic sodium, 15 to 30 percent of ethylene glycol silicon ether and 30 to 60 percent of water. The preparation method comprises the following steps of: adding 30 to 60 percent of water into an enamel reaction kettle, starting a stirrer, and heating to raise the temperature to be between 30 and 40 DEG C; adding 1 to 15 percent of glycol ether and 15 to 45 percent of didodecyl dicarboxylic sodium into the reaction kettle, controlling the temperature and stirring for 1 hour; and adding 15 to 30 percent of ethylene glycol silicon ether into the reaction kettle, controlling the temperature to be between 40 and 80 DEG C, and reacting for 1 to 2 hours to obtain the water-lock releasing agent. The water-lock releasing agent is strong in surface activity and low in use level, can well maintain the permeability of a low-permeability reservoir and release water-lock damages, and is used in the working fluid such as fracturing fluid, perforating fluid, well control fluid and the like.

Description

field of invention [0001] The invention relates to an oilfield chemical agent used in the construction of oil and gas recovery operations, in particular to a low-permeability oil reservoir dehydration and locking agent and a preparation method thereof, which are mainly used in well fluids such as fracturing fluid, perforating fluid and well killing fluid middle. Background technique [0002] Low-permeability reservoirs generally have the characteristics of high capillary pressure, strong water sensitivity, small pore throats, poor permeability, and severe heterogeneity. In the process of oil production, the well fluid is prone to capillary self-absorption in the water phase, causing a large amount of well fluid to enter the reservoir. The poor permeability of low-permeability reservoirs makes it difficult or even impossible to flow back the well fluid that invades the reservoirs, resulting in water lock damage. Domestic and foreign studies have shown that water lock damage...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the technical problems that a single type of water-blocking agent is difficult to take into account factors such as geology, reservoir conditions and construction techniques of low-permeability reservoirs, the effect of releasing water-locking damage is not ideal, and the scope of application is limited. The first aspect of the present invention is to provide a surface It is a low-permeability oil reservoir water-blocking agent with strong activity, which makes it easy to flow back into the well fluid, effectively relieves water-locking damage, and maintains the permeability of the reservoir; the second is to provide a preparation method for low-permeability oil reservoir water-blocking agent