CN-122016561-A - Method for testing initial setting time of polymer cement paste plugging agent

Abstract

The invention belongs to the technical field of plugging of oil-water wells, and particularly relates to a method for testing initial setting time of a polymer cement paste plugging agent. The testing method comprises the following steps of measuring the viscosity of a sample of the polymer cement paste plugging agent by using a viscometer, and obtaining the initial setting time of the polymer cement paste plugging agent when the viscosity of the sample reaches 9000-10000 Pa.s. The method for testing the initial setting time of the polymer cement paste plugging agent uses a viscosity-time curve to test the initial setting time of the polymer cement paste plugging agent, and determines the viscosity numerical range during initial setting. The testing method is safe and reliable, and the measured initial setting time data is real and accurate, so that the construction safety and the construction effect of the oilfield plugging site are effectively ensured.

Inventors

• ZOU XIAOPING
• WANG HAO
• LI MINGLIANG
• ZHANG QIUHONG
• WANG BIN
• CAO ZUOWEI
• YUAN QIUJU
• YIN QINGGUO
• GAO HONGBIN

Assignees

• 中国石油天然气股份有限公司

Dates

Publication Date

20260512

Application Date

20241112

Claims (8)

1. 1. The method for testing the initial setting time of the polymer cement paste plugging agent is characterized by comprising the following steps of: And measuring the sample viscosity of the polymer cement paste plugging agent by using a viscometer, and obtaining the initial setting time of the polymer cement paste plugging agent when the sample viscosity reaches 9000-10000 Pa.s.
2. 2. The method of testing according to claim 1, wherein the viscometer is a rotational viscometer.
3. 3. The test method according to claim 2, comprising the steps of: s1, pouring a polymer cement paste plugging agent sample into a sample cell of a rotary viscometer, and adjusting the rotation rate and the measurement temperature; S2, starting the viscometer every certain time, measuring the viscosity of the sample, and when the viscosity reaches 9000-10000 Pa.s, obtaining the initial setting time of the polymer cement paste plugging agent.
4. 4. A test method according to claim 3, wherein in step S1, the rotation rate is adjusted to 3-30 rpm, and/or the measured temperature is the actual temperature in the oil-water well.
5. 5. The method according to claim 3, wherein in step S2, the viscometer is started every 10 to 30 minutes.
6. 6. The method according to any one of claims 3 to 5, wherein the volume ratio of cement paste to resin polymer in the polymer cement paste plugging agent is (1-3): 1.
7. 7. The method of claim 6, wherein the cement slurry has a density of 1.70-1.85g/cm 3 .
8. 8. The method according to claim 6, wherein the initial viscosity of the resin polymer is 2000mpa.s or less.

Description

Method for testing initial setting time of polymer cement paste plugging agent Technical Field The invention belongs to the technical field of plugging of oil-water wells, and particularly relates to a method for testing initial setting time of a polymer cement paste plugging agent. Background The plugging measure of the oil-water well is one of important matching measures for improving the yield of the oil-water well and ensuring the safe production of the oil field in the development and construction of the oil field, and the cement material is the most widely applied inorganic cementing material in the plugging measure of the oil field, and has the advantages of high strength, low permeability, easily obtained raw materials, simple and easy production and the like, but also has the defects of large brittleness of a solidified body, poor corrosion resistance and insufficient durability, and needs to be modified. According to the research that the resin polymer has good elasticity and plasticity due to the molecular chain structure and the self-rotation property of chain links or chain segments in molecules, the resin polymer is added into a cement-based material according to a certain proportion to be compounded to form the polymer cement paste plugging agent, so that the problems of high brittleness, low impermeability and insufficient durability of the hardened cement paste can be solved. The resin polymers commonly used in the oil field at present mainly comprise latex polymer resin, unsaturated polyester resin, phenolic resin, urea resin, epoxy resin and the like. Because the oil field shutoff construction operation window period is longer, in order to guarantee construction safety, the polymer cement paste plugging agent needs to have enough liquid pumping time, and the plugging agent can be displaced to a target position during construction, so that the initial setting time of the polymer cement paste plugging agent needs to be tested. The method for testing the initial setting time of the oilfield cement paste plugging agent mainly adopts a thickening time evaluation method in GB/T19139-2012 oil well cement test method, namely, the cement paste plugging agent is prepared and is put into a thickening instrument with blades, the experimental temperature and pressure are set, and the time used when the cement paste consistency reaches 100BC is the initial setting time. The evaluation method can dynamically reflect the consistency change of the cement paste plugging agent under the high-temperature and high-pressure simulated oil reservoir, and determine the initial setting time of the cement paste, and is high in accuracy, but is not suitable for testing the initial setting time of the polymer cement paste plugging agent. In view of this, the present invention has been made. Disclosure of Invention The invention aims to provide a method for testing the initial setting time of a polymer cement paste plugging agent, which is safe and reliable, and the measured initial setting time data is true and accurate, so that the construction safety and the construction effect of an oilfield plugging site are effectively ensured. In order to overcome the defects in the prior art, the invention provides the following technical scheme: a method for testing the initial setting time of a polymer cement paste plugging agent comprises the following steps: And measuring the sample viscosity of the polymer cement paste plugging agent by using a viscometer, and obtaining the initial setting time of the polymer cement paste plugging agent when the sample viscosity reaches 9000-10000 Pa.s. Further, the viscometer is a rotary viscometer. Further, the method comprises the following steps: s1, pouring a polymer cement paste plugging agent sample into a sample cell of a rotary viscometer, and adjusting the rotation rate and the measurement temperature; S2, starting the viscometer every certain time, measuring the viscosity of the sample, and when the viscosity reaches 9000-10000 Pa.s, obtaining the initial setting time of the polymer cement paste plugging agent. Further, in step S1, the rotation rate is adjusted to 3-30 rpm, and/or the measured temperature is the actual temperature in the oil-water well. Further, in step S2, the viscometer is started every 10-30 min. Further, in the polymer cement paste plugging agent, the volume ratio of cement paste to resin polymer is (1-3): 1. Further, the density of the cement paste is 1.70-1.85g/cm 3. Further, the initial viscosity of the resin polymer is less than or equal to 2000mPa.s. Compared with the prior art, the technical scheme of the invention has at least the following technical effects: The method for testing the initial setting time of the polymer cement paste plugging agent uses a viscosity-time curve to test the initial setting time of the polymer cement paste plugging agent, and determines the viscosity numerical range during initial setting. The testing method is safe and