CN-121994686-A - Reservoir pore structure corrosion simulation experiment method, device and system

CN121994686ACN 121994686 ACN121994686 ACN 121994686ACN-121994686-A

Abstract

The invention provides a reservoir pore structure corrosion simulation experiment method, device and system, wherein the method comprises the steps of determining the generation parameters of organic acid of hydrocarbon source rock in a target research area according to a typical hydrocarbon source rock sample in the target research area; the method comprises the steps of placing a reservoir sample in a target research area into a sample corrosion assembly, setting an experimental confining pressure and an experimental temperature interval for the reservoir sample according to a stratum pressure and a stratum temperature interval, starting a nuclear magnetic resonance device of the sample corrosion assembly to test pore throat radius distribution in the reservoir sample, injecting organic acid into the reservoir sample, and obtaining a change rule of a pore structure in the organic acid corrosion process according to test data of the nuclear magnetic resonance device. Based on the technical scheme of the invention, a continuous flow corrosion experiment of the organic acid on the tight reservoir under the actual temperature and pressure condition can be carried out, the change of the pore structure of the tight reservoir can be detected in real time, the real-time change rule of the pore structure of the tight reservoir can be quantitatively represented through the on-line nuclear magnetism detection, and a basis is provided for the prediction of the favorable enrichment region of petroleum.

Inventors

CAO ZHE
WEI PEI
GAO MIN
ZHANG ZHONGMIN

Assignees

中国石油化工股份有限公司
中国石油化工股份有限公司石油勘探开发研究院

Dates

Publication Date: 20260508
Application Date: 20241104

Claims (14)

1. The reservoir pore structure corrosion simulation experiment method is characterized by comprising the following steps of: Determining generation parameters of organic acid of the source rock of the target research area according to a typical source rock sample of the target research area, wherein the generation parameters at least comprise the type of the organic acid, the concentration of the organic acid, the formation pressure and the formation temperature interval; Placing a reservoir sample of the target research area into a sample corrosion assembly, and setting an experimental confining pressure and an experimental temperature interval for the reservoir sample according to the stratum pressure and the stratum temperature interval; starting a nuclear magnetic resonance device of the sample corrosion assembly to test pore throat radius distribution in the reservoir sample, and injecting organic acid into the reservoir sample to gradually increase the experimental temperature from the lower limit of the experimental temperature interval to the upper limit of the experimental temperature interval; and when the experimental temperature reaches the upper limit of the interval, obtaining the change rule of the pore structure in the organic acid dissolution process according to the test data of the nuclear magnetic resonance device.
2. The reservoir pore structure corrosion simulation experiment method of claim 1, wherein determining the generation parameters of the organic acids of the source rock of the target research area from the typical source rock sample of the target research area comprises the following sub-steps: Carrying out hydrocarbon generation simulation experiments by using the typical hydrocarbon source rock sample, and determining the type of organic acid, the concentration of the organic acid and the formation temperature interval in the generation parameters according to experimental results; basin simulation is carried out according to the geological background of the target research area, and the formation pressure when the organic acid in the production parameters is produced is determined.
3. A reservoir pore structure corrosion simulation experiment method according to claim 1 or 2, wherein the injection of organic acid into the reservoir sample comprises the sub-steps of: according to the type and the concentration of the organic acid in the generation parameters, selecting the organic acid with the corresponding type and concentration; pumping an organic acid at a predetermined temperature into the reservoir sample, the predetermined temperature being determined based on a current specific temperature value of the reservoir sample.
4. The method of claim 1, wherein placing the reservoir sample of the target study area into a sample erosion assembly sets an experimental confining pressure and an experimental temperature interval for the reservoir sample according to the formation pressure and the formation temperature interval, comprising the sub-steps of: placing the reservoir sample in a sample compartment corresponding to a nuclear magnetic resonance device of the sample erosion assembly; pumping a confining pressure medium into an interlayer of the sample bin by using a first confining pressure maintaining unit, wherein the pumping pressure of the confining pressure medium is matched with the stratum pressure, and the pumping temperature is matched with the lower limit of the stratum temperature interval; and receiving the confining pressure medium output from the interlayer by using a second confining pressure maintaining unit.
5. The reservoir pore structure corrosion simulation experiment method of claim 4, wherein the confining pressure medium output from the sandwich is received by a second confining pressure maintenance unit, further comprising: and enabling the pressure of the second confining pressure maintaining unit to be smaller than the pumping pressure of the confining pressure medium by the first confining pressure maintaining unit.
6. The method of simulating corrosion of a pore structure of claim 4, wherein gradually increasing the experimental temperature from a lower interval limit to an upper interval limit of the experimental temperature interval comprises the sub-steps of: And changing the temperature of the confining pressure medium pumped by the first confining pressure maintaining unit, so that the experimental temperature gradually increases from the lower limit of the experimental temperature interval to the upper limit of the interval.
7. A reservoir pore structure corrosion simulation experiment method as claimed in claim 1 or 6, wherein the temperature change rate at which the experimental temperature gradually increases from the lower limit of the experimental temperature interval to the upper limit of the interval thereof is 10 ℃ per hour.
8. The reservoir pore structure corrosion simulation experiment method according to claim 1, wherein the method for obtaining the change rule of the pore structure in the organic acid corrosion process according to the test data of the nuclear magnetic resonance device comprises the following steps: and determining the distribution condition and the change condition of pores corresponding to the corresponding relaxation time T 2 in the reservoir sample in the corrosion process according to the test data of the nuclear magnetic resonance device, and obtaining the change rule of the pore structure in the organic acid corrosion process.
9. A reservoir pore structure erosion simulation experiment device, comprising: A sample erosion assembly comprising a nuclear magnetic resonance device and a sample compartment disposed within the nuclear magnetic resonance device for placement of a reservoir sample; An environment simulation assembly connected with the interlayer of the sample bin through a pipeline and used for injecting confining pressure medium with corresponding temperature and pressure into the interlayer so as to simulate the formation pressure and the formation temperature, and An organic acid injection assembly in communication with the interior of the sample compartment through a conduit for injecting an organic acid into the sample compartment to erode the reservoir sample.
10. The corrosion simulation experiment device for the pore structure of the reservoir according to claim 9, wherein the sample bin comprises a cylindrical confining pressure device, the confining pressure device is vertically arranged, a clamp holder is respectively arranged at the top end and the bottom end of the confining pressure device so as to enclose an inner space of the sample bin, the confining pressure device is made of an elastic material, and the interlayer is constructed in the confining pressure device; Wherein the organic acid injection assembly is connected to the holder at the tip through a pipe to communicate with the inside of the sample cartridge through a passage constructed in the holder at the tip.
11. The reservoir pore structure corrosion simulation experiment apparatus of claim 10, further comprising a solution collection assembly connected to the holder at a bottom end by a conduit to communicate with the interior of the sample cartridge through a channel configured within the holder at the bottom end.
12. The reservoir pore structure corrosion simulation experiment device according to claim 9, wherein the environment simulation assembly comprises a first confining pressure maintaining unit and a second confining pressure maintaining unit which are identical in structure, and the confining pressure maintaining unit comprises a confining pressure medium container and a confining pressure pump which are connected through a pipeline; The two confining pressure medium containers are respectively communicated with the interlayer through pipelines, the pumping pressure of the confining pressure pump of the first confining pressure maintaining unit is larger than that of the confining pressure pump of the second confining pressure maintaining unit, and the confining pressure medium container of the first confining pressure maintaining unit is arranged in the incubator.
13. The reservoir pore structure corrosion simulation experiment apparatus of claim 9, wherein the organic acid injection assembly comprises an organic acid container placed in an incubator and an injection pump connected with the organic acid container through a pipe, the organic acid container being in communication with the sample compartment through a pipe.
14. A reservoir pore structure corrosion simulation experiment system, comprising the reservoir pore structure corrosion simulation experiment device according to any one of claims 9 to 13, and a data acquisition device electrically connected with the experiment device, wherein the data acquisition device is used for acquiring various temperature and pressure data of the experiment device and test data of a nuclear magnetic resonance device.

Description

Reservoir pore structure corrosion simulation experiment method, device and system Technical Field The invention relates to the technical field of unconventional oil and gas reservoir pore structure research, in particular to a reservoir pore structure corrosion simulation experiment method, device and system. Background Compact oil is widely distributed in oil-containing gas basins in China, and is an important field of oil and gas yield increase. The compact oil reservoir develops a micro-nano pore throat system widely, and the micro-pore structure is an important factor affecting the transportation and aggregation of oil and gas into a reservoir. A large amount of organic acid is released in the thermal evolution process of organic matters in the hydrocarbon source rock, carbonate minerals and silicate minerals in adjacent reservoirs are eroded, and then large-scale secondary pores are formed, so that the pore structure of a compact reservoir is changed, and petroleum transportation and accumulation are affected. At present, the corrosion effect of organic acid is studied at home and abroad, and the related device and technical scheme of the corrosion effect or the diagenetic effect of the organic acid are developed in the field of petroleum geology. For example, researchers in the current field propose an experimental scheme of the corrosion effect of organic acid on a tight oil reservoir, which adopts a reaction kettle as an experimental container, through static corrosion experiments, discusses a thermodynamic model of the decarboxylation reaction of the organic acid, and also propose a simulation experimental scheme of the corrosion of the reservoir, which adopts a continuous flow corrosion method under high temperature and high pressure conditions, and researches the influence of the corrosion on the reservoir by analyzing the reaction solution, the reservoir minerals, the sample mass and the volume after the corrosion, and also propose an analysis scheme of the corrosion effect of carbonate rock, which compares the pore structure of the reservoir before and after the corrosion of the organic acid by a CT scanning means, and discusses the influence of the corrosion effect on the pore structure of the reservoir. However, most of the researches including the prior proposal at present aim at the research of the organic acid dissolution mechanism, the change of the solution ion content and the characterization of static pore structures before and after dissolution, do not relate to the change of the pore structures in the dissolution process, and particularly cannot realize the real-time detection and analysis of the pore structures of the tight reservoir under the action of the organic acid dissolution, so that the real-time change rule of the pore structures of the tight reservoir in the organic acid dissolution process cannot be effectively determined. Disclosure of Invention In order to solve the problem that the prior art cannot realize real-time detection and analysis of a pore structure of a tight reservoir under the action of organic acid dissolution and cannot determine the real-time change rule of the pore structure of the tight reservoir in the process of organic acid dissolution, the invention provides a simulated experiment method, a simulated experiment device and a simulated experiment system for dissolution of the pore structure of the tight reservoir. In a first aspect, the invention provides a reservoir pore structure corrosion simulation experiment method, which comprises the following steps: Determining generation parameters of organic acid of the source rock of the target research area according to a typical source rock sample of the target research area, wherein the generation parameters at least comprise the type of the organic acid, the concentration of the organic acid, the formation pressure and the formation temperature interval; Placing a reservoir sample of the target research area into a sample corrosion assembly, and setting an experimental confining pressure and an experimental temperature interval for the reservoir sample according to the stratum pressure and the stratum temperature interval; starting a nuclear magnetic resonance device of the sample corrosion assembly to test pore throat radius distribution in the reservoir sample, and injecting organic acid into the reservoir sample to gradually increase the experimental temperature from the lower limit of the experimental temperature interval to the upper limit of the experimental temperature interval; and when the experimental temperature reaches the upper limit of the interval, obtaining the change rule of the pore structure in the organic acid dissolution process according to the test data of the nuclear magnetic resonance device. In one embodiment, determining a production parameter of an organic acid of a source rock of a target study area from a typical source rock sample of the target study area comprises the s