Weight method isothermal adsorption test and volumetric method isothermal adsorption test combined binary gas adsorption test method

Abstract

The invention provides a weight method isothermal adsorption test and volumetric method isothermal adsorption test combined binary gas adsorption test method. The binary gas adsorption mass of a sample under the conditions of target temperature and pressure is obtained by measuring through a weight method isothermal adsorption test; the binary gas adsorption volume (standard state) of the sample under the conditions of target temperature and pressure is obtained by measuring through volumetric method isothermal adsorption test; the test results of the weight method isothermal adsorption test and the volumetric method isothermal adsorption test are combined; the standard density of the binary phase of an adsorbed phase is obtained by calculating, and is combined with the respective standarddensity of component gases for calculating to obtain the total adsorption amount (molar weight) of binary gas of the sample and the composition ratio of the binary gas of the adsorbed phase, and thus, a curve of the total adsorption amount of the binary gas of the sample and a curve of the change of the composition ratio of the binary gas of the adsorbed phase with the pressure are established. According to the test method, the influence of the volume of the adsorbed phase is not considered, the gas composition of the adsorbed phase is directly calculated, and the test precision is higher; additional gas chromatography analysis is not required; and the test process is simpler.

Description

technical field [0001] The invention relates to the field of shale gas research, in particular to a binary gas adsorption test method combining a gravimetric method and a volumetric isothermal adsorption test. Background technique [0002] As an unconventional oil and gas resource with huge resources, shale gas has made great breakthroughs in its exploration and development in the past decade. Adsorbed gas is an important occurrence form of shale gas, and its proportion in shale gas can reach 85% (Curtis et.al, 2002; Zhang Jinchuan et al., 2004). The adsorption performance of shale gas directly determines the content of adsorbed gas in shale intervals, which is mainly determined by isothermal adsorption test, which is one of the research hotspots in the field of shale gas. The existing isothermal adsorption test method is mainly one-component gas isothermal adsorption test. According to its test principle, it can be divided into volumetric isothermal adsorption test and gra...

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Problems solved by technology

[0007] (1) In the process of testing and data calculation, the volume of the gas in the adsorption phase is ignored, and there are defects in the testing principle, resulting in low accuracy;

[0008] (2) Multiple gas chromatographic analyzes need to be performed simultaneously during the test, resulting in cumbersome test procedures and high test costs

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