A method and device for detecting adsorption parameters of adsorbed crude oil in tight reservoirs

Abstract

The invention provides a method and a device for detecting adsorption parameters of tight reservoir adsorbed state crude oil. The method comprises the following steps: acquiring and generating a test rock sample, and testing and acquiring the oil content W1 of the test rock sample; drilling a plunger rock sample from the test rock sample so as to test the overburden pressure properties, acquiring the porosity Phi, and acquiring the oil saturation So according to the oil content W1 and the porosity Phi; performing oil scrubbing treatment on the tested rock sample, and generating an oil scrubbing rock sample; generating a pore size-pore volume distribution curve of the oil scrubbing rock sample by virtue of a high-pressure mercury intrusion method, and determining the lower limit Rm of the oil content according to the oil saturation So; performing nanometer CT imaging test on the oil scrubbing rock sample, and determining the isolated pore surface area Sc; grinding the oil scrubbing rock sample, testing the specific area distribution of pores by utilizing N2 adsorption, determining the specific surface area SN of the pores, and generating the effective pore area S; testing according to a QCM-D instrument, and generating the density pa of the adsorbed crude oil and the adsorption quantity Ka of the tested rock sample in unit area; and finally generating the adsorbed oil quantity W and adsorbed oil ratio Wa of the tested rock sample according to the parameters.

Description

Technical field [0001] The invention relates to a testing technology for petroleum exploration, and in particular to a method and a device for detecting the adsorption parameters of adsorbed crude oil in tight reservoirs. Background technique [0002] Tight reservoirs generally have the characteristics of low porosity, low permeability, and nano-scale pore throat development. Although the exploitation of tight reservoirs has been achieved through large-scale horizontal wells and reservoir reconstruction technologies such as fracturing, exploration at home and abroad has confirmed that its production has an early high-yield, rapidly decreasing "L"-shaped distribution. Foreign countries use the long-term monitoring of single well production to calculate EUR, and use the FORSPAN method to estimate regional recoverable resources. However, the production of tight reservoirs in China lacks long-term monitoring and the influencing factors of the production curve are complex. Therefore, ...

AI Technical Summary

Problems solved by technology

However, in the current nuclear magnetic resonance technology, T 2 When converted into pore radius, the treatment of surface relaxation and diffusion relaxation is often neglected, which leads to the inability to accurately determine the pore radius. Furthermore, T 2 Cut-off value identification affects the quantification of mobile fluids

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