Rod blockage prevention liquid for carbon dioxide huff-puff enhanced oil recovery and injection method thereof

Abstract

The invention discloses rod blockage prevention liquid for carbon dioxide huff-puff enhanced oil recovery and an injection method thereof, which mainly solve the problem of well blockage caused by a large quantity of paraffin deposits on the inner wall of an oil pipe during carbon dioxide huff-puff enhanced oil recovery operation. The rod blockage prevention liquid comprises the following components in percentage by mass: 40 to 50 percent of glycol, 3 to 5 percent of carbon dioxide corrosion inhibitor, 5 percent of anti-expanding agent, 2 percent of anti-scaling agent, 2 percent of surfactantand the balance of water. A pressure gauge (1), a one-way valve (2), a valve (3) and an agent feeder are arranged at the port of a well mouth casing; the rod blockage prevention liquid is injected into a well through the agent feeder; a pumping unit is not stopped during the injection of the agents; when a large amount of rod blockage prevention liquid occurs at the well mouth, the pumping unit is stopped at a lower dead point; and an agent injection device is disassembled and the port of the well mouth casing is closed well. The rod blockage prevention liquid can soften the paraffin depositsin the oil pipe and prevent well blockage; and the injection method of the rod blockage prevention liquid is simple, is easy to operate and is low in cost.

Description

technical field [0001] The invention relates to an anti-rod stuck fluid for oil recovery in an oil field and a filling method thereof, in particular to an anti-rod stuck fluid for enhanced oil recovery with carbon dioxide huff and puff and a filling method thereof. Background technique [0002] Carbon dioxide huff and puff enhanced oil recovery is an oil enhancement technology that has emerged in recent years. However, since the temperature of carbon dioxide injection is lower than minus 20°C and the injection time is about 10 hours, it is easy to cause severe wax deposition on the inner wall of the tubing, resulting in well jamming. At present, to solve the well stuck problem in the carbon dioxide injection construction, the method of operation hot washing is mainly used. This method not only pollutes the formation and affects production, but also costs a lot. Contents of the invention [0003] The present invention aims to overcome the problem in the background technolog...

AI Technical Summary

Problems solved by technology

[0002] Carbon dioxide huff and puff enhanced oil recovery is an oil enhancement technology that has emerged in recent years. However, since the temperature of carbon dioxide injection is lower than minus 20°C and the injection time is about 10 hours, it is easy to cause serious wax deposition on the inner wall of the tubing, resulting in well jamming.

At present, to solve the problem of well stuck in carbon dioxide injection construction, the method of hot washing is mainly used. This method not only pollutes the formation but also affects production, and it is expensive

Images