阅读说明：本技术 一种用于干酪根的溶胀方法 (Swelling method for kerogen ) 是由 梁天 邹艳荣 詹兆文 林晓慧 于 2021-08-26 设计创作，主要内容包括：本发明属于溶胀方法的技术领域,具体涉及一种用于干酪根的溶胀方法。本发明的对干酪根的溶胀方法设备要求简单,操作简单,检测失误率低；可以对溶胀现象进行分段研究,即可以探究干酪根最大留烃能力,也可以准确的反映在溶胀过程中干酪根与烃类物质之间的相互作用；操作可控性高,能够准确研究干酪根对不同烃类物质的滞留能力,精确度不受外界条件控制,目标烃类物质可自由选择或自行配置,指导干酪根生排烃研究；本发明能够反映相同有机溶剂在不同干酪根内的溶解能力,在研究不同干酪根沉积环境、烃源岩性质等方向拥有重要意义。(The invention belongs to the technical field of swelling methods, and particularly relates to a swelling method for kerogen. The swelling method for kerogen has the advantages of simple equipment requirement, simple operation and low detection error rate; the swelling phenomenon can be studied in a segmented manner, namely the maximum hydrocarbon retention capacity of the kerogen can be explored, and the interaction between the kerogen and hydrocarbon substances in the swelling process can be accurately reflected; the operation controllability is high, the retention capacity of the kerogen to different hydrocarbon substances can be accurately researched, the accuracy is not controlled by external conditions, and the target hydrocarbon substance can be freely selected or self-configured to guide the research on the hydrocarbon generation and discharge of the kerogen; the invention can reflect the dissolving capacity of the same organic solvent in different kerogen and has important significance in the directions of researching different kerogen deposition environments, hydrocarbon source rock properties and the like.)

1. A swelling method for kerogen, comprising the steps of:

1) setting 19 glass bottles, and quantitatively adding dried and pure kerogen samples respectively, wherein the weights of the samples are recorded as m1 respectively, and the total number of the samples is 19;

2) calculating the weight m2 of the corresponding liquid organic matter according to the weight m1 of the kerogen sample at normal temperature and normal pressure;

3) sample point calculation: in 19 samples, the weight m2 of the liquid organic matter of each sample is in an increasing relationship of 5% to the total weight m1+ m2 of the sample;

4) adding a liquid organic matter reagent into the kerogen sample to form a mixture according to the proportion in the step 3), and standing;

5) after standing, observing whether the 19 samples have flowable liquid hydrocarbon or not, and if the 19 samples contain free-flowing reagents, indicating that the amount of the reagents added at the ratio point of the samples exceeds the hydrocarbon retention capacity of kerogen, and the hydrocarbon discharge effect of the kerogen already occurs at the ratio point;

6) selecting an interval between the last sample proportion point X% of the non-flowable liquid hydrocarbon and the first flowable liquid hydrocarbon (X + 5)% to prepare 4 sample proportion points which are respectively (X + 1)%, (X + 2)%, (X + 3)%, and (X + 4)%;

7) and (5) repeating the steps 4) to 5) according to the sample proportion point set in the step 6), and determining the dissolving capacity of the kerogen to the organic reagent until the actual proportion precision of the liquid organic matter is 0.1-1%.

2. Swelling method for kerogen according to claim 1, characterized in that in step 3) the ratio m2/(m1+ m2) x 100% and the liquid organic matter ratio of the 19 samples is 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, respectively.

3. The swelling method for kerogen according to claim 2, wherein the swelling ratios of kerogen for the 19 liquid organic matter ratios are 1.05, 1.11, 1.18, 1.25, 1.33, 1.43, 1.54, 1.67, 1.82, 2.00, 2.22, 2.50, 2.86, 3.33, 4.00, 5.00, respectively.

4. The swelling process for kerogen of claim 1, wherein the liquid organic hydrocarbon comprises n-heptylbenzene or n-hexadecane.

5. The swelling method for kerogen according to claim 1, wherein the accuracy of step 7) is 0.1% by repeating the operation of 3 to 5 to obtain more accurate results.

Technical Field

The invention belongs to the technical field of swelling methods, and particularly relates to a swelling method for kerogen.

Background

Swelling refers to the swelling phenomenon of high molecular polymers in organic reagents, and is an important research method for researching the interaction between solid and liquid organic matters. At present, four mature methods such as a swelling instrument method, a centrifugal method, a vibration method, a fiber image method and the like exist.

Kerogen as a matrix of shale oil resources is an important research object in oil-gas geochemistry, and shale oil as an important supplement of traditional petroleum resources, the exploitability and the practicability of the shale oil are proved, and the shale oil has important significance for protecting national energy safety and promoting long-term and orderly development of the economic society of China. Kerogen produces shale oil under the action of hydrocarbon generation (kerogen is a large-molecular geological organism which can be cracked under the conditions of high temperature and high pressure, small-molecular substances fall off to form petroleum and natural gas, the cracking process is hydrocarbon generation), a large amount of hydrocarbon substances are retained in kerogen due to the interaction between organic matters, the hydrocarbon substances are called retained hydrocarbon, and the swelling method is an important means for researching the hydrocarbon retention capacity of the kerogen.

Disclosure of Invention

In view of the above problems, the present invention is directed to provide a swelling method for kerogen, which can reflect the dissolving capacity of the same organic solvent in different kerogens and has important significance in the research of different kerogen deposition environments, hydrocarbon source rock properties, and the like.

The technical content of the invention is as follows:

the invention provides a swelling method for kerogen, which comprises the following steps:

1) setting 19 glass bottles, and quantitatively adding dried and pure kerogen samples respectively, wherein the weights of the samples are recorded as m1 respectively, and the total number of the samples is 19;

2) calculating the weight m2 of the corresponding liquid organic matter according to the weight m1 of the kerogen sample at normal temperature and normal pressure;

3) sample point calculation: in 19 samples, the weight m2 of the liquid organic matter of each sample is in an increasing relationship of 5% to the total weight m1+ m2 of the sample;

4) adding a liquid organic matter reagent into the kerogen sample to form a mixture according to the proportion in the step 3), and standing;

5) after standing, observing whether the 19 samples have flowable liquid hydrocarbon or not, and if the 19 samples contain free-flowing reagents, indicating that the amount of the reagents added at the ratio point of the samples exceeds the hydrocarbon retention capacity of kerogen, and the hydrocarbon discharge effect of the kerogen already occurs at the ratio point;

6) selecting an interval between the last sample proportion point X% of the non-flowable liquid hydrocarbon and the first flowable liquid hydrocarbon (X + 5)% to prepare 4 sample proportion points which are respectively (X + 1)%, (X + 2)%, (X + 3)%, and (X + 4)%;

7) according to the sample proportion point set in the step 6), repeating the steps 4) to 5), and determining the dissolving capacity of the kerogen to the organic reagent until the actual proportion precision of the liquid organic matter is 0.1-1%;

step 3) ofThe liquid organic matter proportions of the 19 samples were 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, and 95%, respectively;

the swelling ratios of kerogen corresponding to the 19 liquid organic matter ratios are 1.05, 1.11, 1.18, 1.25, 1.33, 1.43, 1.54, 1.67, 1.82, 2.00, 2.22, 2.50, 2.86, 3.33, 4.00 and 5.00 respectively, as shown in fig. 1, which is helpful for converting the weight ratio of the invention into the swelling ratio;

the liquid organic hydrocarbon comprises n-heptylbenzene or n-hexadecane;

and 7) repeating the operation of 3-5 to obtain a more accurate result when the accuracy is 0.1%.

The invention has the following beneficial effects:

the swelling method for kerogen of the invention has the following advantages: 1) the equipment requirement is simple, the operation can be completed only by basic glass bottles and balances, complex instruments such as a high-speed centrifuge, a concussion instrument, a swelling instrument and the like are not needed, the operation can be completed in all basic pretreatment laboratories and even oil and gas exploitation sites, the requirements of relevant equipment of other methods on the experimental environment are high, and partial laboratories are difficult to develop;

2) the detection error rate is low, the swelling phenomenon is judged by using the weight instead of the volume, the detection difficulty is greatly reduced, accurate data can be obtained more easily, and the volume detection method after swelling in other methods mainly detects the change of the height of a sample in a sample tube, but the accumulation form of the sample can be changed after oscillation and centrifugation, so that the detection of the volume of the sample is influenced to a great extent;

4) the swelling phenomenon can be studied in a segmented manner, namely the maximum hydrocarbon retention capacity of kerogen can be explored, and the interaction between the kerogen and hydrocarbon substances in the swelling process can be accurately reflected, the operation is simplest at present, segmented detection cannot be realized by using the most widely-applied centrifugal method, only the final result can be obtained, and the swelling instrument method can realize segmentation, but has higher cost and great experimental difficulty;

5) the operation controllability is high, the retention capacity of the kerogen to different hydrocarbon substances can be accurately researched, the accuracy is not controlled by external conditions, and the target hydrocarbon substance can be freely selected or self-configured to guide the research on the hydrocarbon generation and discharge of the kerogen;

the invention can reflect the dissolving capacity of the same organic solvent in different kerogen and has important significance in the directions of researching different kerogen deposition environments, hydrocarbon source rock properties and the like.

Drawings

FIG. 1 is a graph showing the conversion of the swelling ratio of kerogen according to the present invention.

Detailed Description

The present invention is described in further detail in the following detailed description with reference to specific embodiments, which are intended to be illustrative only and not to be limiting of the scope of the invention, as various equivalent modifications of the invention will become apparent to those skilled in the art after reading the present invention and are intended to be included within the scope of the appended claims.

All the raw materials and reagents of the invention are conventional market raw materials and reagents unless otherwise specified.

Example 1

Selecting a pure kerogen sample separated from oil shale of a Ponga chinensis nest group in the Chongdong Mappie region for swelling:

1) setting 19 glass bottles, and quantitatively adding dried and pure kerogen samples respectively, wherein the weights of the samples are recorded as m1 respectively, and the total number of the samples is 19;

2) calculating the weight m2 of the corresponding liquid organic matter according to the weight m1 of the kerogen sample at normal temperature and normal pressure;

3) sample point calculation: in 19 samples, the weight m2 of the liquid organic matter of each sample is in an increasing relationship of 5% to the total weight m1+ m2 of the sample;

the above-mentionedThe liquid organic matter proportions of the 19 samples were 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, and 95%, respectively;

4) respectively reacting n-heptylbenzene (C)₁₃H₂O) and n-hexadecane (C)₁₆H₃₄) Adding two liquid organic matter reagents into the kerogen sample, standing the mixture in the proportion in the step 3);

in the swelling ratio measurement of the embodiment, for a standard field environment, a manual liquid transfer device with poor accuracy is used for adding liquid hydrocarbon, the accuracy is 1mg, and the swelling ratio of a sample is formed by preliminary rough estimation;

TABLE 1 soluble amount (mg) of the two reagents for the named oil shale kerogen

5) After standing, observing whether the 19 samples have flowable liquid hydrocarbon or not, and if the 19 samples contain free-flowing reagents, indicating that the amount of the reagents added at the ratio point of the samples exceeds the hydrocarbon retention capacity of kerogen, and the hydrocarbon discharge effect of the kerogen already occurs at the ratio point;

as can be seen from Table 1, both the majestic kerogen and the two organic agents were saturated when the liquid organic content reached 55%, and the swelling ratio was 2.22. The majestic kerogen is shown to have the maximum dissolving capacity of about 1.2 times of the weight of the kerogen under the natural state of normal temperature and pressure, has stronger hydrocarbon retention capacity, has no selectivity for dissolving different hydrocarbon substances (saturated hydrocarbon and aromatic hydrocarbon), and can evenly dissolve the two substances.

Example 2

Selecting a pure kerogen sample separated from shale of the grass furrow group of the Juniperus communis of the Xinjiang, swelling, adopting the steps 1 to 4 as shown in the example 1, and selecting n-heptylbenzene (C)₁₃H₂₀) And n-hexadecane (C)₁₆H₃₄) Two reagents are used as representatives of aromatic hydrocarbon and saturated hydrocarbon liquid organic matters;

the swelling method of the reed grass ditch mud shale kerogen is researched in a standard laboratory, and an electric pipette is adopted to add a reagent, so that the precision is 0.01 mg.

TABLE 2 dissolved amount (mg) of Phragmites communis ditch shale kerogen to two reagents

As can be seen from Table 2, the combination of the experimental phenomena resulted in the fact that Phragmites communis ditch kerogen and two organic reagents were saturated when the liquid organic matter reached 65-70%, at which time the swelling ratio was 2.86-3.33, followed by further swelling, and found a 1% swelling ratio interval.

TABLE 3 dissolved amount (mg) of Phragmites communis ditch shale kerogen to two reagents

It can be seen from Table 3 that, in combination with the swelling test, n-heptylbenzene was saturated in the range of 67-68% and n-hexadecane in the range of 65-66%, the swelling ratios of the two liquid hydrocarbons were in the ranges of 2.86-2.94 and 3.03-3.12, respectively.

Then, the swelling ratio of the Phragmites communis mozzarella kera root to the n-heptylbenzene and the n-hexadecane respectively is subjected to further swelling experiments.

TABLE 4 dissolved amount (mg) of Phragmites communis ditch shale kerogen to n-heptylbenzene

As can be seen from Table 4, the swelling ratio of Phragmites communis ditch mud shale kerogen to n-heptylbenzene is saturated in the range of 3.18 to 3.21(68.60 to 68.80%), thus increasing the swelling ratio of 3.19 (68.70%) of the sample point, and determining that the sample has no mobile liquid hydrocarbon at 3.19 and a mobile liquid hydrocarbon at 3.21, the aromatic hydrocarbon swelling ratio of Phragmites communis ditch mud shale kerogen is 3.19.

TABLE 5 dissolved amount of Phragmites communis ditch shale kerogen to n-hexadecane (mg)

As can be seen from Table 5, the swelling ratio of Phragmites communis ditch mud shale kerogen to n-heptylbenzene is increased by saturation in the range of 2.976 to 2.994(66.40 to 66.60%), so that the sample point is increased by 2.985 (68.50%) and no liquid hydrocarbon flow is determined at 2.985 swelling ratio of the sample, while a liquid hydrocarbon flow is determined at 2.994, whereby the swelling ratio of the saturated hydrocarbon compound of Phragmites communis ditch mud shale kerogen is 2.985.

Through the swelling experiments, the swelling parameters of the Phragmites communis ditch mud shale kerogen to the two hydrocarbon compounds are finally accurately confirmed, compared with the famous oil shale kerogen, the experiments add liquid hydrocarbon to an electric pipettor with higher accuracy in a standard laboratory, and the accurate swelling rate parameter determination can be completed through the method.